msh.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Minix shell port for busybox
   4  *
   5  * This version of the Minix shell was adapted for use in busybox
   6  * by Erik Andersen <andersee@debian.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  *
  22  * Original copyright notice is retained at the end of this file.
  23  */
  24
  25 #include <ctype.h>
  26 #include <dirent.h>
  27 #include <errno.h>
  28 #include <fcntl.h>
  29 #include <limits.h>
  30 #include <setjmp.h>
  31 #include <signal.h>
  32 #include <stddef.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <time.h>
  37 #include <unistd.h>
  38 #include <sys/stat.h>
  39 #include <sys/times.h>
  40 #include <sys/types.h>
  41 #include <sys/wait.h>
  42
  43 #include "cmdedit.h"
  44 #include "busybox.h"
  45
  46
  47 /* -------- sh.h -------- */
  48 /*
  49  * shell
  50  */
  51
  52 #define LINELIM 2100
  53 #define NPUSH   8       /* limit to input nesting */
  54
  55 #define NOFILE  20      /* Number of open files */
  56 #define NUFILE  10      /* Number of user-accessible files */
  57 #define FDBASE  10      /* First file usable by Shell */
  58
  59 /*
  60  * values returned by wait
  61  */
  62 #define WAITSIG(s) ((s)&0177)
  63 #define WAITVAL(s) (((s)>>8)&0377)
  64 #define WAITCORE(s) (((s)&0200)!=0)
  65
  66 /*
  67  * library and system defintions
  68  */
  69 typedef void xint;      /* base type of jmp_buf, for not broken compilers */
  70
  71 /*
  72  * shell components
  73  */
  74
  75 #define QUOTE   0200
  76
  77 #define NOBLOCK ((struct op *)NULL)
  78 #define NOWORD  ((char *)NULL)
  79 #define NOWORDS ((char **)NULL)
  80 #define NOPIPE  ((int *)NULL)
  81
  82 /*
  83  * Description of a command or an operation on commands.
  84  * Might eventually use a union.
  85  */
  86 struct op {
  87         int     type;   /* operation type, see below */
  88         char    **words;        /* arguments to a command */
  89         struct  ioword  **ioact;        /* IO actions (eg, < > >>) */
  90         struct op *left;
  91         struct op *right;
  92         char    *str;   /* identifier for case and for */
  93 };
  94
  95 #define TCOM    1       /* command */
  96 #define TPAREN  2       /* (c-list) */
  97 #define TPIPE   3       /* a | b */
  98 #define TLIST   4       /* a [&;] b */
  99 #define TOR     5       /* || */
 100 #define TAND    6       /* && */
 101 #define TFOR    7
 102 #define TDO     8
 103 #define TCASE   9
 104 #define TIF     10
 105 #define TWHILE  11
 106 #define TUNTIL  12
 107 #define TELIF   13
 108 #define TPAT    14      /* pattern in case */
 109 #define TBRACE  15      /* {c-list} */
 110 #define TASYNC  16      /* c & */
 111
 112 /*
 113  * actions determining the environment of a process
 114  */
 115 #define BIT(i)  (1<<(i))
 116 #define FEXEC   BIT(0)  /* execute without forking */
 117
 118 /*
 119  * flags to control evaluation of words
 120  */
 121 #define DOSUB   1       /* interpret $, `, and quotes */
 122 #define DOBLANK 2       /* perform blank interpretation */
 123 #define DOGLOB  4       /* interpret [?* */
 124 #define DOKEY   8       /* move words with `=' to 2nd arg. list */
 125 #define DOTRIM  16      /* trim resulting string */
 126
 127 #define DOALL   (DOSUB|DOBLANK|DOGLOB|DOKEY|DOTRIM)
 128
 129 static  char    **dolv;
 130 static  int     dolc;
 131 static  int     exstat;
 132 static  char    gflg;
 133 static  int     interactive;    /* Is this an interactive shell */
 134 static  int     execflg;
 135 static  int     multiline;      /* \n changed to ; */
 136 static  struct  op      *outtree;       /* result from parser */
 137
 138 static  xint    *failpt;
 139 static  xint    *errpt;
 140 static  struct brkcon   *brklist;
 141 static  int     isbreak;
 142 static int newfile(char *s);
 143 static char *findeq(char *cp);
 144 static char *cclass(char *p, int sub);
 145 static void initarea(void);
 146 extern int shell_main(int argc, char **argv);
 147
 148
 149 struct  brkcon {
 150         jmp_buf brkpt;
 151         struct  brkcon  *nextlev;
 152 } ;
 153
 154 /*
 155  * redirection
 156  */
 157 struct ioword {
 158         short   io_unit;        /* unit affected */
 159         short   io_flag;        /* action (below) */
 160         char    *io_name;       /* file name */
 161 };
 162 #define IOREAD  1       /* < */
 163 #define IOHERE  2       /* << (here file) */
 164 #define IOWRITE 4       /* > */
 165 #define IOCAT   8       /* >> */
 166 #define IOXHERE 16      /* ${}, ` in << */
 167 #define IODUP   32      /* >&digit */
 168 #define IOCLOSE 64      /* >&- */
 169
 170 #define IODEFAULT (-1)  /* token for default IO unit */
 171
 172 static  struct  wdblock *wdlist;
 173 static  struct  wdblock *iolist;
 174
 175 /*
 176  * parsing & execution environment
 177  */
 178 static struct   env {
 179         char    *linep;
 180         struct  io      *iobase;
 181         struct  io      *iop;
 182         xint    *errpt;
 183         int     iofd;
 184         struct  env     *oenv;
 185 } e;
 186
 187 /*
 188  * flags:
 189  * -e: quit on error
 190  * -k: look for name=value everywhere on command line
 191  * -n: no execution
 192  * -t: exit after reading and executing one command
 193  * -v: echo as read
 194  * -x: trace
 195  * -u: unset variables net diagnostic
 196  */
 197 static  char    *flag;
 198
 199 static  char    *null;  /* null value for variable */
 200 static  int     intr;   /* interrupt pending */
 201
 202 static  char    *trap[_NSIG+1];
 203 static  char    ourtrap[_NSIG+1];
 204 static  int     trapset;        /* trap pending */
 205
 206 static  int     heedint;        /* heed interrupt signals */
 207
 208 static  int     yynerrs;        /* yacc */
 209
 210 static  char    line[LINELIM];
 211 static  char    *elinep;
 212
 213 /*
 214  * other functions
 215  */
 216 static int (*inbuilt(char *s ))(void);
 217
 218 static char *rexecve (char *c , char **v, char **envp );
 219 static char *space (int n );
 220 static char *strsave (char *s, int a );
 221 static char *evalstr (char *cp, int f );
 222 static char *putn (int n );
 223 static char *itoa (unsigned u, int n );
 224 static char *unquote (char *as );
 225 static struct var *lookup (char *n );
 226 static int rlookup (char *n );
 227 static struct wdblock *glob (char *cp, struct wdblock *wb );
 228 static int my_getc( int ec);
 229 static int subgetc (int ec, int quoted );
 230 static char **makenv (void);
 231 static char **eval (char **ap, int f );
 232 static int setstatus (int s );
 233 static int waitfor (int lastpid, int canintr );
 234
 235 static void onintr (int s ); /* SIGINT handler */
 236
 237 static int newenv (int f );
 238 static void quitenv (void);
 239 static void err (char *s );
 240 static int anys (char *s1, char *s2 );
 241 static int any (int c, char *s );
 242 static void next (int f );
 243 static void setdash (void);
 244 static void onecommand (void);
 245 static void runtrap (int i );
 246 static int gmatch (char *s, char *p );
 247
 248 /*
 249  * error handling
 250  */
 251 static void leave (void); /* abort shell (or fail in subshell) */
 252 static void fail (void);         /* fail but return to process next command */
 253 static void warn (char *s );
 254 static void sig (int i );        /* default signal handler */
 255
 256
 257
 258 /* -------- area stuff -------- */
 259
 260 #define REGSIZE         sizeof(struct region)
 261 #define GROWBY          256
 262 //#define       SHRINKBY   64
 263 #undef  SHRINKBY
 264 #define FREE 32767
 265 #define BUSY 0
 266 #define ALIGN (sizeof(int)-1)
 267
 268
 269 struct region {
 270         struct  region *next;
 271         int     area;
 272 };
 273
 274
 275
 276 /* -------- grammar stuff -------- */
 277 typedef union {
 278         char    *cp;
 279         char    **wp;
 280         int     i;
 281         struct  op *o;
 282 } YYSTYPE;
 283 #define WORD    256
 284 #define LOGAND  257
 285 #define LOGOR   258
 286 #define BREAK   259
 287 #define IF      260
 288 #define THEN    261
 289 #define ELSE    262
 290 #define ELIF    263
 291 #define FI      264
 292 #define CASE    265
 293 #define ESAC    266
 294 #define FOR     267
 295 #define WHILE   268
 296 #define UNTIL   269
 297 #define DO      270
 298 #define DONE    271
 299 #define IN      272
 300 #define YYERRCODE 300
 301
 302 /* flags to yylex */
 303 #define CONTIN  01      /* skip new lines to complete command */
 304
 305 #define SYNTAXERR       zzerr()
 306 static struct op *pipeline(int cf );
 307 static struct op *andor(void);
 308 static struct op *c_list(void);
 309 static int synio(int cf );
 310 static void musthave (int c, int cf );
 311 static struct op *simple(void);
 312 static struct op *nested(int type, int mark );
 313 static struct op *command(int cf );
 314 static struct op *dogroup(int onlydone );
 315 static struct op *thenpart(void);
 316 static struct op *elsepart(void);
 317 static struct op *caselist(void);
 318 static struct op *casepart(void);
 319 static char **pattern(void);
 320 static char **wordlist(void);
 321 static struct op *list(struct op *t1, struct op *t2 );
 322 static struct op *block(int type, struct op *t1, struct op *t2, char **wp );
 323 static struct op *newtp(void);
 324 static struct op *namelist(struct op *t );
 325 static char **copyw(void);
 326 static void word(char *cp );
 327 static struct ioword **copyio(void);
 328 static struct ioword *io (int u, int f, char *cp );
 329 static void zzerr(void);
 330 static void yyerror(char *s );
 331 static int yylex(int cf );
 332 static int collect(int c, int c1 );
 333 static int dual(int c );
 334 static void diag(int ec );
 335 static char *tree(unsigned size );
 336
 337 /* -------- var.h -------- */
 338
 339 struct  var {
 340         char    *value;
 341         char    *name;
 342         struct  var     *next;
 343         char    status;
 344 };
 345 #define COPYV   1       /* flag to setval, suggesting copy */
 346 #define RONLY   01      /* variable is read-only */
 347 #define EXPORT  02      /* variable is to be exported */
 348 #define GETCELL 04      /* name & value space was got with getcell */
 349
 350 static  struct  var     *vlist;         /* dictionary */
 351
 352 static  struct  var     *homedir;       /* home directory */
 353 static  struct  var     *prompt;        /* main prompt */
 354 static  struct  var     *cprompt;       /* continuation prompt */
 355 static  struct  var     *path;          /* search path for commands */
 356 static  struct  var     *shell;         /* shell to interpret command files */
 357 static  struct  var     *ifs;           /* field separators */
 358
 359 static int yyparse (void);
 360 static struct var *lookup (char *n );
 361 static void setval (struct var *vp, char *val );
 362 static void nameval (struct var *vp, char *val, char *name );
 363 static void export (struct var *vp );
 364 static void ronly (struct var *vp );
 365 static int isassign (char *s );
 366 static int checkname (char *cp );
 367 static int assign (char *s, int cf );
 368 static void putvlist (int f, int out );
 369 static int eqname (char *n1, char *n2 );
 370
 371 static int execute (struct op *t, int *pin, int *pout, int act );
 372
 373 /* -------- io.h -------- */
 374 /* io buffer */
 375 struct iobuf {
 376   unsigned id;                          /* buffer id */
 377   char buf[512];                        /* buffer */
 378   char *bufp;                           /* pointer into buffer */
 379   char *ebufp;                          /* pointer to end of buffer */
 380 };
 381
 382 /* possible arguments to an IO function */
 383 struct ioarg {
 384         char    *aword;
 385         char    **awordlist;
 386         int     afile;          /* file descriptor */
 387         unsigned afid;          /* buffer id */
 388         long    afpos;          /* file position */
 389         struct iobuf *afbuf;    /* buffer for this file */
 390 };
 391 //static struct ioarg ioargstack[NPUSH];
 392 #define AFID_NOBUF      (~0)
 393 #define AFID_ID         0
 394
 395 /* an input generator's state */
 396 struct  io {
 397         int     (*iofn)();
 398         struct  ioarg   *argp;
 399         int     peekc;
 400         char    prev;           /* previous character read by readc() */
 401         char    nlcount;        /* for `'s */
 402         char    xchar;          /* for `'s */
 403         char    task;           /* reason for pushed IO */
 404 };
 405 //static        struct  io      iostack[NPUSH];
 406 #define XOTHER  0       /* none of the below */
 407 #define XDOLL   1       /* expanding ${} */
 408 #define XGRAVE  2       /* expanding `'s */
 409 #define XIO     3       /* file IO */
 410
 411 /* in substitution */
 412 #define INSUB() (e.iop->task == XGRAVE || e.iop->task == XDOLL)
 413
 414 /*
 415  * input generators for IO structure
 416  */
 417 static int nlchar (struct ioarg *ap );
 418 static int strchar (struct ioarg *ap );
 419 static int qstrchar (struct ioarg *ap );
 420 static int filechar (struct ioarg *ap );
 421 static int herechar (struct ioarg *ap );
 422 static int linechar (struct ioarg *ap );
 423 static int gravechar (struct ioarg *ap, struct io *iop );
 424 static int qgravechar (struct ioarg *ap, struct io *iop );
 425 static int dolchar (struct ioarg *ap );
 426 static int wdchar (struct ioarg *ap );
 427 static void scraphere (void);
 428 static void freehere (int area );
 429 static void gethere (void);
 430 static void markhere (char *s, struct ioword *iop );
 431 static int herein (char *hname, int xdoll );
 432 static int run (struct ioarg *argp, int (*f)());
 433
 434 /*
 435  * IO functions
 436  */
 437 static int eofc (void);
 438 static int readc (void);
 439 static void unget (int c );
 440 static void ioecho (int c );
 441 static void prs (char *s );
 442 static void prn (unsigned u );
 443 static void closef (int i );
 444 static void closeall (void);
 445
 446 /*
 447  * IO control
 448  */
 449 static void pushio (struct ioarg *argp, int (*fn)());
 450 static int remap (int fd );
 451 static int openpipe (int *pv );
 452 static void closepipe (int *pv );
 453 static struct io *setbase (struct io *ip );
 454
 455 static  struct  ioarg   temparg;        /* temporary for PUSHIO */
 456 #define PUSHIO(what,arg,gen) ((temparg.what = (arg)),pushio(&temparg,(gen)))
 457 #define RUN(what,arg,gen) ((temparg.what = (arg)), run(&temparg,(gen)))
 458
 459 /* -------- word.h -------- */
 460
 461 #define NSTART  16      /* default number of words to allow for initially */
 462
 463 struct  wdblock {
 464         short   w_bsize;
 465         short   w_nword;
 466         /* bounds are arbitrary */
 467         char    *w_words[1];
 468 };
 469
 470 static struct wdblock *addword (char *wd, struct wdblock *wb );
 471 static struct wdblock *newword (int nw );
 472 static char **getwords (struct wdblock *wb );
 473
 474 /* -------- area.h -------- */
 475
 476 /*
 477  * storage allocation
 478  */
 479 static char *getcell (unsigned nbytes );
 480 static void garbage (void);
 481 static void setarea (char *cp, int a );
 482 static int getarea (char *cp );
 483 static void freearea (int a );
 484 static void freecell (char *cp );
 485 static  int     areanum;        /* current allocation area */
 486
 487 #define NEW(type) (type *)getcell(sizeof(type))
 488 #define DELETE(obj)     freecell((char *)obj)
 489
 490
 491 /* -------- misc stuff -------- */
 492
 493 static int forkexec (struct op *t, int *pin, int *pout, int act, char **wp, int *pforked );
 494 static int iosetup (struct ioword *iop, int pipein, int pipeout );
 495 static void echo(char **wp );
 496 static struct op **find1case (struct op *t, char *w );
 497 static struct op *findcase (struct op *t, char *w );
 498 static void brkset(struct brkcon *bc );
 499 static int dolabel(void);
 500 static int dohelp(void);
 501 static int dochdir(struct op *t );
 502 static int doshift(struct op *t );
 503 static int dologin(struct op *t );
 504 static int doumask(struct op *t );
 505 static int doexec(struct op *t );
 506 static int dodot(struct op *t );
 507 static int dowait(struct op *t );
 508 static int doread(struct op *t );
 509 static int doeval(struct op *t );
 510 static int dotrap(struct op *t );
 511 static int getsig(char *s );
 512 static void setsig (int n, void (*f)());
 513 static int getn(char *as );
 514 static int dobreak(struct op *t );
 515 static int docontinue(struct op *t );
 516 static int brkcontin (char *cp, int val );
 517 static int doexit(struct op *t );
 518 static int doexport(struct op *t );
 519 static int doreadonly(struct op *t );
 520 static void rdexp (char **wp, void (*f)(), int key);
 521 static void badid(char *s );
 522 static int doset(struct op *t );
 523 static void varput (char *s, int out );
 524 static int dotimes(void);
 525 static int expand (char *cp, struct wdblock **wbp, int f );
 526 static char *blank(int f );
 527 static int dollar(int quoted );
 528 static int grave(int quoted );
 529 static void globname (char *we, char *pp );
 530 static char *generate (char *start1, char *end1, char *middle, char *end );
 531 static int anyspcl(struct wdblock *wb );
 532 static int xstrcmp (char *p1, char *p2 );
 533 static void glob0 (char *a0, unsigned int a1, int a2, int (*a3)(char *, char *));
 534 static void glob1 (char *base, char *lim );
 535 static void glob2 (char *i, char *j );
 536 static void glob3 (char *i, char *j, char *k );
 537 static void readhere (char **name, char *s, int ec );
 538 static void pushio(struct ioarg *argp, int (*fn)());
 539 static int xxchar(struct ioarg *ap );
 540
 541 struct  here {
 542         char    *h_tag;
 543         int     h_dosub;
 544         struct  ioword *h_iop;
 545         struct  here    *h_next;
 546 };
 547
 548 static  char    *signame[] = {
 549         "Signal 0",
 550         "Hangup",
 551         (char *)NULL,   /* interrupt */
 552         "Quit",
 553         "Illegal instruction",
 554         "Trace/BPT trap",
 555         "Abort",
 556         "Bus error",
 557         "Floating Point Exception",
 558         "Killed",
 559         "SIGUSR1",
 560         "SIGSEGV",
 561         "SIGUSR2",
 562         (char *)NULL,   /* broken pipe */
 563         "Alarm clock",
 564         "Terminated",
 565 };
 566 #define NSIGNAL (sizeof(signame)/sizeof(signame[0]))
 567
 568 struct res {
 569         char *r_name;
 570         int       r_val;
 571 };
 572 static struct res restab[] = {
 573     {"for",             FOR},
 574     {"case",    CASE},
 575     {"esac",    ESAC},
 576     {"while",   WHILE},
 577     {"do",              DO},
 578     {"done",    DONE},
 579     {"if",              IF},
 580     {"in",              IN},
 581     {"then",    THEN},
 582     {"else",    ELSE},
 583     {"elif",    ELIF},
 584     {"until",   UNTIL},
 585     {"fi",              FI},
 586
 587     {";;",              BREAK},
 588     {"||",              LOGOR},
 589     {"&&",              LOGAND},
 590     {"{",               '{'},
 591     {"}",               '}'},
 592     {0,         0},
 593 };
 594
 595
 596 struct builtincmd {
 597         const char *name;
 598         int (*builtinfunc)();
 599 };
 600 static const struct     builtincmd      builtincmds[] = {
 601     {".",               dodot},
 602     {":",               dolabel},
 603     {"break",   dobreak},
 604     {"cd",              dochdir},
 605     {"continue",docontinue},
 606     {"eval",    doeval},
 607     {"exec",    doexec},
 608     {"exit",    doexit},
 609     {"export",  doexport},
 610     {"help",    dohelp},
 611     {"login",   dologin},
 612     {"newgrp",  dologin},
 613     {"read",    doread},
 614     {"readonly",doreadonly},
 615     {"set",             doset},
 616     {"shift",   doshift},
 617     {"times",   dotimes},
 618     {"trap",    dotrap},
 619     {"umask",   doumask},
 620     {"wait",    dowait},
 621     {0,0}
 622 };
 623
 624 /* Globals */
 625 extern  char    **environ;      /* environment pointer */
 626 static char     **dolv;
 627 static int      dolc;
 628 static int      exstat;
 629 static char     gflg;
 630 static int      interactive;    /* Is this an interactive shell */
 631 static int      execflg;
 632 static int      multiline;      /* \n changed to ; */
 633 static struct   op      *outtree;       /* result from parser */
 634 static xint     *failpt;
 635 static xint     *errpt;
 636 static struct   brkcon  *brklist;
 637 static int      isbreak;
 638 static struct   wdblock *wdlist;
 639 static struct   wdblock *iolist;
 640 static char     *trap[_NSIG+1];
 641 static char     ourtrap[_NSIG+1];
 642 static int      trapset;        /* trap pending */
 643 static int      yynerrs;        /* yacc */
 644 static char     line[LINELIM];
 645 static struct   var     *vlist;         /* dictionary */
 646 static struct   var     *homedir;       /* home directory */
 647 static struct   var     *prompt;        /* main prompt */
 648 static struct   var     *cprompt;       /* continuation prompt */
 649 static struct   var     *path;          /* search path for commands */
 650 static struct   var     *shell;         /* shell to interpret command files */
 651 static struct   var     *ifs;           /* field separators */
 652 static struct   ioarg ioargstack[NPUSH];
 653 static struct   io      iostack[NPUSH];
 654 static int      areanum;        /* current allocation area */
 655 static int      intr;
 656 static int      inparse;
 657 static char     flags['z'-'a'+1];
 658 static char     *flag = flags-'a';
 659 static char     *elinep = line+sizeof(line)-5;
 660 static char     *null   = "";
 661 static int      heedint =1;
 662 static struct env e ={line, iostack, iostack-1, (xint *)NULL, FDBASE, (struct env *)NULL};
 663 static void (*qflag)(int) = SIG_IGN;
 664 static char     shellname[] = "/bin/sh";
 665 static char     search[] = ":/bin:/usr/bin";
 666 static  int     startl;
 667 static  int     peeksym;
 668 static  int     nlseen;
 669 static  int     iounit = IODEFAULT;
 670 static  YYSTYPE yylval;
 671 static struct iobuf sharedbuf = {AFID_NOBUF};
 672 static struct iobuf mainbuf = {AFID_NOBUF};
 673 static unsigned bufid = AFID_ID;        /* buffer id counter */
 674 static struct ioarg temparg = {0, 0, 0, AFID_NOBUF, 0};
 675 static  struct here *inhere;            /* list of hear docs while parsing */
 676 static  struct here *acthere;           /* list of active here documents */
 677 static  struct region *areabot;         /* bottom of area */
 678 static  struct region *areatop;         /* top of area */
 679 static  struct region *areanxt;         /* starting point of scan */
 680 static void * brktop;
 681 static void * brkaddr;
 682
 683
 684 #ifdef BB_FEATURE_COMMAND_EDITING
 685 char * current_prompt;
 686 unsigned int shell_context;
 687 #endif
 688
 689
 690 /* -------- sh.c -------- */
 691 /*
 692  * shell
 693  */
 694
 695
 696 extern int shell_main(int argc, char **argv)
 697 {
 698         register int f;
 699         register char *s;
 700         int cflag;
 701         char *name, **ap;
 702         int (*iof)();
 703
 704         initarea();
 705         if ((ap = environ) != NULL) {
 706                 while (*ap)
 707                         assign(*ap++, !COPYV);
 708                 for (ap = environ; *ap;)
 709                         export(lookup(*ap++));
 710         }
 711         closeall();
 712         areanum = 1;
 713
 714         shell = lookup("SHELL");
 715         if (shell->value == null)
 716                 setval(shell, shellname);
 717         export(shell);
 718
 719         homedir = lookup("HOME");
 720         if (homedir->value == null)
 721                 setval(homedir, "/");
 722         export(homedir);
 723
 724         setval(lookup("$"), itoa(getpid(), 5));
 725
 726         path = lookup("PATH");
 727         if (path->value == null)
 728                 setval(path, search);
 729         export(path);
 730
 731         ifs = lookup("IFS");
 732         if (ifs->value == null)
 733                 setval(ifs, " \t\n");
 734
 735         prompt = lookup("PS1");
 736 #ifdef BB_FEATURE_SH_FANCY_PROMPT
 737         if (prompt->value == null)
 738 #endif
 739                 setval(prompt, "$ ");
 740         if (geteuid() == 0) {
 741                 setval(prompt, "# ");
 742                 prompt->status &= ~EXPORT;
 743         }
 744         cprompt = lookup("PS2");
 745 #ifdef BB_FEATURE_SH_FANCY_PROMPT
 746         if (cprompt->value == null)
 747 #endif
 748                 setval(cprompt, "> ");
 749
 750         iof = filechar;
 751         cflag = 0;
 752         name = *argv++;
 753         if (--argc >= 1) {
 754                 if(argv[0][0] == '-' && argv[0][1] != '\0') {
 755                         for (s = argv[0]+1; *s; s++)
 756                                 switch (*s) {
 757                                 case 'c':
 758                                         prompt->status &= ~EXPORT;
 759                                         cprompt->status &= ~EXPORT;
 760                                         setval(prompt, "");
 761                                         setval(cprompt, "");
 762                                         cflag = 1;
 763                                         if (--argc > 0)
 764                                                 PUSHIO(aword, *++argv, iof = nlchar);
 765                                         break;
 766
 767                                 case 'q':
 768                                         qflag = SIG_DFL;
 769                                         break;
 770
 771                                 case 's':
 772                                         /* standard input */
 773                                         break;
 774
 775                                 case 't':
 776                                         prompt->status &= ~EXPORT;
 777                                         setval(prompt, "");
 778                                         iof = linechar;
 779                                         break;
 780
 781                                 case 'i':
 782                                         interactive++;
 783                                 default:
 784                                         if (*s>='a' && *s<='z')
 785                                                 flag[(int)*s]++;
 786                                 }
 787                 } else {
 788                         argv--;
 789                         argc++;
 790                 }
 791                 if (iof == filechar && --argc > 0) {
 792                         setval(prompt, "");
 793                         setval(cprompt, "");
 794                         prompt->status &= ~EXPORT;
 795                         cprompt->status &= ~EXPORT;
 796                         if (newfile(name = *++argv))
 797                                 exit(1);
 798                 }
 799         }
 800         setdash();
 801         if (e.iop < iostack) {
 802                 PUSHIO(afile, 0, iof);
 803                 if (isatty(0) && isatty(1) && !cflag) {
 804                         interactive++;
 805                         printf( "\n\n" BB_BANNER " Built-in shell (msh)\n");
 806                         printf( "Enter 'help' for a list of built-in commands.\n\n");
 807                 }
 808         }
 809         signal(SIGQUIT, qflag);
 810         if (name && name[0] == '-') {
 811                 interactive++;
 812                 if ((f = open(".profile", 0)) >= 0)
 813                         next(remap(f));
 814                 if ((f = open("/etc/profile", 0)) >= 0)
 815                         next(remap(f));
 816         }
 817         if (interactive)
 818                 signal(SIGTERM, sig);
 819         if (signal(SIGINT, SIG_IGN) != SIG_IGN)
 820                 signal(SIGINT, onintr);
 821         dolv = argv;
 822         dolc = argc;
 823         dolv[0] = name;
 824         if (dolc > 1) {
 825                 for (ap = ++argv; --argc > 0;) {
 826                         if (assign(*ap = *argv++, !COPYV)) {
 827                                 dolc--; /* keyword */
 828                         } else {
 829                                 ap++;
 830                         }
 831                 }
 832         }
 833         setval(lookup("#"), putn((--dolc < 0) ? (dolc = 0) : dolc));
 834
 835         for (;;) {
 836                 if (interactive && e.iop <= iostack) {
 837 #ifdef BB_FEATURE_COMMAND_EDITING
 838                         current_prompt=prompt->value;
 839 #else
 840                         prs(prompt->value);
 841 #endif
 842                 }
 843                 onecommand();
 844         }
 845 }
 846
 847 static void
 848 setdash()
 849 {
 850         register char *cp;
 851         register int c;
 852         char m['z'-'a'+1];
 853
 854         cp = m;
 855         for (c='a'; c<='z'; c++)
 856                 if (flag[c])
 857                         *cp++ = c;
 858         *cp = 0;
 859         setval(lookup("-"), m);
 860 }
 861
 862 static int
 863 newfile(s)
 864 register char *s;
 865 {
 866         register int f;
 867
 868         if (strcmp(s, "-") != 0) {
 869                 f = open(s, 0);
 870                 if (f < 0) {
 871                         prs(s);
 872                         err(": cannot open");
 873                         return(1);
 874                 }
 875         } else
 876                 f = 0;
 877         next(remap(f));
 878         return(0);
 879 }
 880
 881 static void
 882 onecommand()
 883 {
 884         register int i;
 885         jmp_buf m1;
 886
 887         while (e.oenv)
 888                 quitenv();
 889         areanum = 1;
 890         freehere(areanum);
 891         freearea(areanum);
 892         garbage();
 893         wdlist = 0;
 894         iolist = 0;
 895         e.errpt = 0;
 896         e.linep = line;
 897         yynerrs = 0;
 898         multiline = 0;
 899         inparse = 1;
 900         intr = 0;
 901         execflg = 0;
 902         setjmp(failpt = m1);    /* Bruce Evans' fix */
 903         if (setjmp(failpt = m1) || yyparse() || intr) {
 904                 while (e.oenv)
 905                         quitenv();
 906                 scraphere();
 907                 if (!interactive && intr)
 908                         leave();
 909                 inparse = 0;
 910                 intr = 0;
 911                 return;
 912         }
 913         inparse = 0;
 914         brklist = 0;
 915         intr = 0;
 916         execflg = 0;
 917         if (!flag['n'])
 918                 execute(outtree, NOPIPE, NOPIPE, 0);
 919         if (!interactive && intr) {
 920                 execflg = 0;
 921                 leave();
 922         }
 923         if ((i = trapset) != 0) {
 924                 trapset = 0;
 925                 runtrap(i);
 926         }
 927 }
 928
 929 static void
 930 fail()
 931 {
 932         longjmp(failpt, 1);
 933         /* NOTREACHED */
 934 }
 935
 936 static void
 937 leave()
 938 {
 939         if (execflg)
 940                 fail();
 941         scraphere();
 942         freehere(1);
 943         runtrap(0);
 944         exit(exstat);
 945         /* NOTREACHED */
 946 }
 947
 948 static void
 949 warn(s)
 950 register char *s;
 951 {
 952         if(*s) {
 953                 prs(s);
 954                 exstat = -1;
 955         }
 956         prs("\n");
 957         if (flag['e'])
 958                 leave();
 959 }
 960
 961 static void
 962 err(s)
 963 char *s;
 964 {
 965         warn(s);
 966         if (flag['n'])
 967                 return;
 968         if (!interactive)
 969                 leave();
 970         if (e.errpt)
 971                 longjmp(e.errpt, 1);
 972         closeall();
 973         e.iop = e.iobase = iostack;
 974 }
 975
 976 static int
 977 newenv(f)
 978 int f;
 979 {
 980         register struct env *ep;
 981
 982         if (f) {
 983                 quitenv();
 984                 return(1);
 985         }
 986         ep = (struct env *) space(sizeof(*ep));
 987         if (ep == NULL) {
 988                 while (e.oenv)
 989                         quitenv();
 990                 fail();
 991         }
 992         *ep = e;
 993         e.oenv = ep;
 994         e.errpt = errpt;
 995         return(0);
 996 }
 997
 998 static void
 999 quitenv()
1000 {
1001         register struct env *ep;
1002         register int fd;
1003
1004         if ((ep = e.oenv) != NULL) {
1005                 fd = e.iofd;
1006                 e = *ep;
1007                 /* should close `'d files */
1008                 DELETE(ep);
1009                 while (--fd >= e.iofd)
1010                         close(fd);
1011         }
1012 }
1013
1014 /*
1015  * Is any character from s1 in s2?
1016  */
1017 static int
1018 anys(s1, s2)
1019 register char *s1, *s2;
1020 {
1021         while (*s1)
1022                 if (any(*s1++, s2))
1023                         return(1);
1024         return(0);
1025 }
1026
1027 /*
1028  * Is character c in s?
1029  */
1030 static int
1031 any(c, s)
1032 register int c;
1033 register char *s;
1034 {
1035         while (*s)
1036                 if (*s++ == c)
1037                         return(1);
1038         return(0);
1039 }
1040
1041 static char *
1042 putn(n)
1043 register int n;
1044 {
1045         return(itoa(n, -1));
1046 }
1047
1048 static char *
1049 itoa(u, n)
1050 register unsigned u;
1051 int n;
1052 {
1053         register char *cp;
1054         static char s[20];
1055         int m;
1056
1057         m = 0;
1058         if (n < 0 && (int) u < 0) {
1059                 m++;
1060                 u = -u;
1061         }
1062         cp = s+sizeof(s);
1063         *--cp = 0;
1064         do {
1065                 *--cp = u%10 + '0';
1066                 u /= 10;
1067         } while (--n > 0 || u);
1068         if (m)
1069                 *--cp = '-';
1070         return(cp);
1071 }
1072
1073 static void
1074 next(f)
1075 int f;
1076 {
1077         PUSHIO(afile, f, filechar);
1078 }
1079
1080 static void
1081 onintr(s)
1082 int s;                          /* ANSI C requires a parameter */
1083 {
1084         signal(SIGINT, onintr);
1085         intr = 1;
1086         if (interactive) {
1087                 if (inparse) {
1088                         prs("\n");
1089                         fail();
1090                 }
1091         }
1092         else if (heedint) {
1093                 execflg = 0;
1094                 leave();
1095         }
1096 }
1097
1098 static char *
1099 space(n)
1100 int n;
1101 {
1102         register char *cp;
1103
1104         if ((cp = getcell(n)) == 0)
1105                 err("out of string space");
1106         return(cp);
1107 }
1108
1109 static char *
1110 strsave(s, a)
1111 register char *s;
1112 int a;
1113 {
1114         register char *cp, *xp;
1115
1116         if ((cp = space(strlen(s)+1)) != NULL) {
1117                 setarea((char *)cp, a);
1118                 for (xp = cp; (*xp++ = *s++) != '\0';)
1119                         ;
1120                 return(cp);
1121         }
1122         return("");
1123 }
1124
1125 /*
1126  * trap handling
1127  */
1128 static void
1129 sig(i)
1130 register int i;
1131 {
1132         trapset = i;
1133         signal(i, sig);
1134 }
1135
1136 static void runtrap(i)
1137 int i;
1138 {
1139         char *trapstr;
1140
1141         if ((trapstr = trap[i]) == NULL)
1142                 return;
1143         if (i == 0)
1144                 trap[i] = 0;
1145         RUN(aword, trapstr, nlchar);
1146 }
1147
1148 /* -------- var.c -------- */
1149
1150 /*
1151  * Find the given name in the dictionary
1152  * and return its value.  If the name was
1153  * not previously there, enter it now and
1154  * return a null value.
1155  */
1156 static struct var *
1157 lookup(n)
1158 register char *n;
1159 {
1160         register struct var *vp;
1161         register char *cp;
1162         register int c;
1163         static struct var dummy;
1164
1165         if (isdigit(*n)) {
1166                 dummy.name = n;
1167                 for (c = 0; isdigit(*n) && c < 1000; n++)
1168                         c = c*10 + *n-'0';
1169                 dummy.status = RONLY;
1170                 dummy.value = c <= dolc? dolv[c]: null;
1171                 return(&dummy);
1172         }
1173         for (vp = vlist; vp; vp = vp->next)
1174                 if (eqname(vp->name, n))
1175                         return(vp);
1176         cp = findeq(n);
1177         vp = (struct var *)space(sizeof(*vp));
1178         if (vp == 0 || (vp->name = space((int)(cp-n)+2)) == 0) {
1179                 dummy.name = dummy.value = "";
1180                 return(&dummy);
1181         }
1182         for (cp = vp->name; (*cp = *n++) && *cp != '='; cp++)
1183                 ;
1184         if (*cp == 0)
1185                 *cp = '=';
1186         *++cp = 0;
1187         setarea((char *)vp, 0);
1188         setarea((char *)vp->name, 0);
1189         vp->value = null;
1190         vp->next = vlist;
1191         vp->status = GETCELL;
1192         vlist = vp;
1193         return(vp);
1194 }
1195
1196 /*
1197  * give variable at `vp' the value `val'.
1198  */
1199 static void
1200 setval(vp, val)
1201 struct var *vp;
1202 char *val;
1203 {
1204         nameval(vp, val, (char *)NULL);
1205 }
1206
1207 /*
1208  * if name is not NULL, it must be
1209  * a prefix of the space `val',
1210  * and end with `='.
1211  * this is all so that exporting
1212  * values is reasonably painless.
1213  */
1214 static void
1215 nameval(vp, val, name)
1216 register struct var *vp;
1217 char *val, *name;
1218 {
1219         register char *cp, *xp;
1220         char *nv;
1221         int fl;
1222
1223         if (vp->status & RONLY) {
1224                 for (xp = vp->name; *xp && *xp != '=';)
1225                         putc(*xp++, stderr);
1226                 err(" is read-only");
1227                 return;
1228         }
1229         fl = 0;
1230         if (name == NULL) {
1231                 xp = space(strlen(vp->name)+strlen(val)+2);
1232                 if (xp == 0)
1233                         return;
1234                 /* make string:  name=value */
1235                 setarea((char *)xp, 0);
1236                 name = xp;
1237                 for (cp = vp->name; (*xp = *cp++) && *xp!='='; xp++)
1238                         ;
1239                 if (*xp++ == 0)
1240                         xp[-1] = '=';
1241                 nv = xp;
1242                 for (cp = val; (*xp++ = *cp++) != '\0';)
1243                         ;
1244                 val = nv;
1245                 fl = GETCELL;
1246         }
1247         if (vp->status & GETCELL)
1248                 freecell(vp->name);    /* form new string `name=value' */
1249         vp->name = name;
1250         vp->value = val;
1251         vp->status |= fl;
1252 }
1253
1254 static void
1255 export(vp)
1256 struct var *vp;
1257 {
1258         vp->status |= EXPORT;
1259 }
1260
1261 static void
1262 ronly(vp)
1263 struct var *vp;
1264 {
1265         if (isalpha(vp->name[0]))       /* not an internal symbol ($# etc) */
1266                 vp->status |= RONLY;
1267 }
1268
1269 static int
1270 isassign(s)
1271 register char *s;
1272 {
1273         if (!isalpha((int)*s))
1274                 return(0);
1275         for (; *s != '='; s++)
1276                 if (*s == 0 || !isalnum(*s))
1277                         return(0);
1278         return(1);
1279 }
1280
1281 static int
1282 assign(s, cf)
1283 register char *s;
1284 int cf;
1285 {
1286         register char *cp;
1287         struct var *vp;
1288
1289         if (!isalpha(*s))
1290                 return(0);
1291         for (cp = s; *cp != '='; cp++)
1292                 if (*cp == 0 || !isalnum(*cp))
1293                         return(0);
1294         vp = lookup(s);
1295         nameval(vp, ++cp, cf == COPYV? (char *)NULL: s);
1296         if (cf != COPYV)
1297                 vp->status &= ~GETCELL;
1298         return(1);
1299 }
1300
1301 static int
1302 checkname(cp)
1303 register char *cp;
1304 {
1305         if (!isalpha(*cp++))
1306                 return(0);
1307         while (*cp)
1308                 if (!isalnum(*cp++))
1309                         return(0);
1310         return(1);
1311 }
1312
1313 static void
1314 putvlist(f, out)
1315 register int f, out;
1316 {
1317         register struct var *vp;
1318
1319         for (vp = vlist; vp; vp = vp->next)
1320                 if (vp->status & f && isalpha(*vp->name)) {
1321                         if (vp->status & EXPORT)
1322                                 write(out, "export ", 7);
1323                         if (vp->status & RONLY)
1324                                 write(out, "readonly ", 9);
1325                         write(out, vp->name, (int)(findeq(vp->name) - vp->name));
1326                         write(out, "\n", 1);
1327                 }
1328 }
1329
1330 static int
1331 eqname(n1, n2)
1332 register char *n1, *n2;
1333 {
1334         for (; *n1 != '=' && *n1 != 0; n1++)
1335                 if (*n2++ != *n1)
1336                         return(0);
1337         return(*n2 == 0 || *n2 == '=');
1338 }
1339
1340 static char *
1341 findeq(cp)
1342 register char *cp;
1343 {
1344         while (*cp != '\0' && *cp != '=')
1345                 cp++;
1346         return(cp);
1347 }
1348
1349 /* -------- gmatch.c -------- */
1350 /*
1351  * int gmatch(string, pattern)
1352  * char *string, *pattern;
1353  *
1354  * Match a pattern as in sh(1).
1355  */
1356
1357 #define CMASK   0377
1358 #define QUOTE   0200
1359 #define QMASK   (CMASK&~QUOTE)
1360 #define NOT     '!'     /* might use ^ */
1361
1362 static int
1363 gmatch(s, p)
1364 register char *s, *p;
1365 {
1366         register int sc, pc;
1367
1368         if (s == NULL || p == NULL)
1369                 return(0);
1370         while ((pc = *p++ & CMASK) != '\0') {
1371                 sc = *s++ & QMASK;
1372                 switch (pc) {
1373                 case '[':
1374                         if ((p = cclass(p, sc)) == NULL)
1375                                 return(0);
1376                         break;
1377
1378                 case '?':
1379                         if (sc == 0)
1380                                 return(0);
1381                         break;
1382
1383                 case '*':
1384                         s--;
1385                         do {
1386                                 if (*p == '\0' || gmatch(s, p))
1387                                         return(1);
1388                         } while (*s++ != '\0');
1389                         return(0);
1390
1391                 default:
1392                         if (sc != (pc&~QUOTE))
1393                                 return(0);
1394                 }
1395         }
1396         return(*s == 0);
1397 }
1398
1399 static char *
1400 cclass(p, sub)
1401 register char *p;
1402 register int sub;
1403 {
1404         register int c, d, not, found;
1405
1406         if ((not = *p == NOT) != 0)
1407                 p++;
1408         found = not;
1409         do {
1410                 if (*p == '\0')
1411                         return((char *)NULL);
1412                 c = *p & CMASK;
1413                 if (p[1] == '-' && p[2] != ']') {
1414                         d = p[2] & CMASK;
1415                         p++;
1416                 } else
1417                         d = c;
1418                 if (c == sub || (c <= sub && sub <= d))
1419                         found = !not;
1420         } while (*++p != ']');
1421         return(found? p+1: (char *)NULL);
1422 }
1423
1424
1425 /* -------- area.c -------- */
1426
1427 /*
1428  * All memory between (char *)areabot and (char *)(areatop+1) is
1429  * exclusively administered by the area management routines.
1430  * It is assumed that sbrk() and brk() manipulate the high end.
1431  */
1432
1433 #define sbrk(X) ({ void * __q = (void *)-1; if (brkaddr + (int)(X) < brktop) { __q = brkaddr; brkaddr+=(int)(X); } __q;})
1434
1435 static void
1436 initarea()
1437 {
1438         brkaddr = malloc(65000);
1439         brktop = brkaddr + 65000;
1440
1441         while ((int)sbrk(0) & ALIGN)
1442                 sbrk(1);
1443         areabot = (struct region *)sbrk(REGSIZE);
1444
1445         areabot->next = areabot;
1446         areabot->area = BUSY;
1447         areatop = areabot;
1448         areanxt = areabot;
1449 }
1450
1451 char *
1452 getcell(nbytes)
1453 unsigned nbytes;
1454 {
1455         register int nregio;
1456         register struct region *p, *q;
1457         register int i;
1458
1459         if (nbytes == 0) {
1460                 puts("getcell(0)");
1461                 abort();
1462         }       /* silly and defeats the algorithm */
1463         /*
1464          * round upwards and add administration area
1465          */
1466         nregio = (nbytes+(REGSIZE-1))/REGSIZE + 1;
1467         for (p = areanxt;;) {
1468                 if (p->area > areanum) {
1469                         /*
1470                          * merge free cells
1471                          */
1472                         while ((q = p->next)->area > areanum && q != areanxt)
1473                                 p->next = q->next;
1474                         /*
1475                          * exit loop if cell big enough
1476                          */
1477                         if (q >= p + nregio)
1478                                 goto found;
1479                 }
1480                 p = p->next;
1481                 if (p == areanxt)
1482                         break;
1483         }
1484         i = nregio >= GROWBY ? nregio : GROWBY;
1485         p = (struct region *)sbrk(i * REGSIZE);
1486         if (p == (struct region *)-1)
1487                 return((char *)NULL);
1488         p--;
1489         if (p != areatop) {
1490                 puts("not contig");
1491                 abort();        /* allocated areas are contiguous */
1492         }
1493         q = p + i;
1494         p->next = q;
1495         p->area = FREE;
1496         q->next = areabot;
1497         q->area = BUSY;
1498         areatop = q;
1499 found:
1500         /*
1501          * we found a FREE area big enough, pointed to by 'p', and up to 'q'
1502          */
1503         areanxt = p + nregio;
1504         if (areanxt < q) {
1505                 /*
1506                  * split into requested area and rest
1507                  */
1508                 if (areanxt+1 > q) {
1509                         puts("OOM");
1510                         abort();        /* insufficient space left for admin */
1511                 }
1512                 areanxt->next = q;
1513                 areanxt->area = FREE;
1514                 p->next = areanxt;
1515         }
1516         p->area = areanum;
1517         return((char *)(p+1));
1518 }
1519
1520 static void
1521 freecell(cp)
1522 char *cp;
1523 {
1524         register struct region *p;
1525
1526         if ((p = (struct region *)cp) != NULL) {
1527                 p--;
1528                 if (p < areanxt)
1529                         areanxt = p;
1530                 p->area = FREE;
1531         }
1532 }
1533
1534 static void
1535 freearea(a)
1536 register int a;
1537 {
1538         register struct region *p, *top;
1539
1540         top = areatop;
1541         for (p = areabot; p != top; p = p->next)
1542                 if (p->area >= a)
1543                         p->area = FREE;
1544 }
1545
1546 static void
1547 setarea(cp,a)
1548 char *cp;
1549 int a;
1550 {
1551         register struct region *p;
1552
1553         if ((p = (struct region *)cp) != NULL)
1554                 (p-1)->area = a;
1555 }
1556
1557 int
1558 getarea(cp)
1559 char *cp;
1560 {
1561         return ((struct region*)cp-1)->area;
1562 }
1563
1564 static void
1565 garbage()
1566 {
1567         register struct region *p, *q, *top;
1568
1569         top = areatop;
1570         for (p = areabot; p != top; p = p->next) {
1571                 if (p->area > areanum) {
1572                         while ((q = p->next)->area > areanum)
1573                                 p->next = q->next;
1574                         areanxt = p;
1575                 }
1576         }
1577 #ifdef SHRINKBY
1578         if (areatop >= q + SHRINKBY && q->area > areanum) {
1579                 brk((char *)(q+1));
1580                 q->next = areabot;
1581                 q->area = BUSY;
1582                 areatop = q;
1583         }
1584 #endif
1585 }
1586
1587 /* -------- csyn.c -------- */
1588 /*
1589  * shell: syntax (C version)
1590  */
1591
1592
1593 int
1594 yyparse()
1595 {
1596         startl  = 1;
1597         peeksym = 0;
1598         yynerrs = 0;
1599         outtree = c_list();
1600         musthave('\n', 0);
1601         return(yynerrs!=0);
1602 }
1603
1604 static struct op *
1605 pipeline(cf)
1606 int cf;
1607 {
1608         register struct op *t, *p;
1609         register int c;
1610
1611         t = command(cf);
1612         if (t != NULL) {
1613                 while ((c = yylex(0)) == '|') {
1614                         if ((p = command(CONTIN)) == NULL)
1615                                 SYNTAXERR;
1616                         if (t->type != TPAREN && t->type != TCOM) {
1617                                 /* shell statement */
1618                                 t = block(TPAREN, t, NOBLOCK, NOWORDS);
1619                         }
1620                         t = block(TPIPE, t, p, NOWORDS);
1621                 }
1622                 peeksym = c;
1623         }
1624         return(t);
1625 }
1626
1627 static struct op *
1628 andor()
1629 {
1630         register struct op *t, *p;
1631         register int c;
1632
1633         t = pipeline(0);
1634         if (t != NULL) {
1635                 while ((c = yylex(0)) == LOGAND || c == LOGOR) {
1636                         if ((p = pipeline(CONTIN)) == NULL)
1637                                 SYNTAXERR;
1638                         t = block(c == LOGAND? TAND: TOR, t, p, NOWORDS);
1639                 }
1640                 peeksym = c;
1641         }
1642         return(t);
1643 }
1644
1645 static struct op *
1646 c_list()
1647 {
1648         register struct op *t, *p;
1649         register int c;
1650
1651         t = andor();
1652         if (t != NULL) {
1653                 if((peeksym = yylex(0)) == '&')
1654                         t = block(TASYNC, t, NOBLOCK, NOWORDS);
1655                 while ((c = yylex(0)) == ';' || c == '&' || (multiline && c == '\n')) {
1656                         if ((p = andor()) == NULL)
1657                                 return(t);
1658                         if((peeksym = yylex(0)) == '&')
1659                                 p = block(TASYNC, p, NOBLOCK, NOWORDS);
1660                         t = list(t, p);
1661                 }
1662                 peeksym = c;
1663         }
1664         return(t);
1665 }
1666
1667
1668 static int
1669 synio(cf)
1670 int cf;
1671 {
1672         register struct ioword *iop;
1673         register int i;
1674         register int c;
1675
1676         if ((c = yylex(cf)) != '<' && c != '>') {
1677                 peeksym = c;
1678                 return(0);
1679         }
1680         i = yylval.i;
1681         musthave(WORD, 0);
1682         iop = io(iounit, i, yylval.cp);
1683         iounit = IODEFAULT;
1684         if (i & IOHERE)
1685                 markhere(yylval.cp, iop);
1686         return(1);
1687 }
1688
1689 static void
1690 musthave(c, cf)
1691 int c, cf;
1692 {
1693         if ((peeksym = yylex(cf)) != c)
1694                 SYNTAXERR;
1695         peeksym = 0;
1696 }
1697
1698 static struct op *
1699 simple()
1700 {
1701         register struct op *t;
1702
1703         t = NULL;
1704         for (;;) {
1705                 switch (peeksym = yylex(0)) {
1706                 case '<':
1707                 case '>':
1708                         (void) synio(0);
1709                         break;
1710
1711                 case WORD:
1712                         if (t == NULL) {
1713                                 t = newtp();
1714                                 t->type = TCOM;
1715                         }
1716                         peeksym = 0;
1717                         word(yylval.cp);
1718                         break;
1719
1720                 default:
1721                         return(t);
1722                 }
1723         }
1724 }
1725
1726 static struct op *
1727 nested(type, mark)
1728 int type, mark;
1729 {
1730         register struct op *t;
1731
1732         multiline++;
1733         t = c_list();
1734         musthave(mark, 0);
1735         multiline--;
1736         return(block(type, t, NOBLOCK, NOWORDS));
1737 }
1738
1739 static struct op *
1740 command(cf)
1741 int cf;
1742 {
1743         register struct op *t;
1744         struct wdblock *iosave;
1745         register int c;
1746
1747         iosave = iolist;
1748         iolist = NULL;
1749         if (multiline)
1750                 cf |= CONTIN;
1751         while (synio(cf))
1752                 cf = 0;
1753         switch (c = yylex(cf)) {
1754         default:
1755                 peeksym = c;
1756                 if ((t = simple()) == NULL) {
1757                         if (iolist == NULL)
1758                                 return((struct op *)NULL);
1759                         t = newtp();
1760                         t->type = TCOM;
1761                 }
1762                 break;
1763
1764         case '(':
1765                 t = nested(TPAREN, ')');
1766                 break;
1767
1768         case '{':
1769                 t = nested(TBRACE, '}');
1770                 break;
1771
1772         case FOR:
1773                 t = newtp();
1774                 t->type = TFOR;
1775                 musthave(WORD, 0);
1776                 startl = 1;
1777                 t->str = yylval.cp;
1778                 multiline++;
1779                 t->words = wordlist();
1780                 if ((c = yylex(0)) != '\n' && c != ';')
1781                         peeksym = c;
1782                 t->left = dogroup(0);
1783                 multiline--;
1784                 break;
1785
1786         case WHILE:
1787         case UNTIL:
1788                 multiline++;
1789                 t = newtp();
1790                 t->type = c == WHILE? TWHILE: TUNTIL;
1791                 t->left = c_list();
1792                 t->right = dogroup(1);
1793                 t->words = NULL;
1794                 multiline--;
1795                 break;
1796
1797         case CASE:
1798                 t = newtp();
1799                 t->type = TCASE;
1800                 musthave(WORD, 0);
1801                 t->str = yylval.cp;
1802                 startl++;
1803                 multiline++;
1804                 musthave(IN, CONTIN);
1805                 startl++;
1806                 t->left = caselist();
1807                 musthave(ESAC, 0);
1808                 multiline--;
1809                 break;
1810
1811         case IF:
1812                 multiline++;
1813                 t = newtp();
1814                 t->type = TIF;
1815                 t->left = c_list();
1816                 t->right = thenpart();
1817                 musthave(FI, 0);
1818                 multiline--;
1819                 break;
1820         }
1821         while (synio(0))
1822                 ;
1823         t = namelist(t);
1824         iolist = iosave;
1825         return(t);
1826 }
1827
1828 static struct op *
1829 dogroup(onlydone)
1830 int onlydone;
1831 {
1832         register int c;
1833         register struct op *mylist;
1834
1835         c = yylex(CONTIN);
1836         if (c == DONE && onlydone)
1837                 return((struct op *)NULL);
1838         if (c != DO)
1839                 SYNTAXERR;
1840         mylist = c_list();
1841         musthave(DONE, 0);
1842         return(mylist);
1843 }
1844
1845 static struct op *
1846 thenpart()
1847 {
1848         register int c;
1849         register struct op *t;
1850
1851         if ((c = yylex(0)) != THEN) {
1852                 peeksym = c;
1853                 return((struct op *)NULL);
1854         }
1855         t = newtp();
1856         t->type = 0;
1857         t->left = c_list();
1858         if (t->left == NULL)
1859                 SYNTAXERR;
1860         t->right = elsepart();
1861         return(t);
1862 }
1863
1864 static struct op *
1865 elsepart()
1866 {
1867         register int c;
1868         register struct op *t;
1869
1870         switch (c = yylex(0)) {
1871         case ELSE:
1872                 if ((t = c_list()) == NULL)
1873                         SYNTAXERR;
1874                 return(t);
1875
1876         case ELIF:
1877                 t = newtp();
1878                 t->type = TELIF;
1879                 t->left = c_list();
1880                 t->right = thenpart();
1881                 return(t);
1882
1883         default:
1884                 peeksym = c;
1885                 return((struct op *)NULL);
1886         }
1887 }
1888
1889 static struct op *
1890 caselist()
1891 {
1892         register struct op *t;
1893
1894         t = NULL;
1895         while ((peeksym = yylex(CONTIN)) != ESAC)
1896                 t = list(t, casepart());
1897         return(t);
1898 }
1899
1900 static struct op *
1901 casepart()
1902 {
1903         register struct op *t;
1904
1905         t = newtp();
1906         t->type = TPAT;
1907         t->words = pattern();
1908         musthave(')', 0);
1909         t->left = c_list();
1910         if ((peeksym = yylex(CONTIN)) != ESAC)
1911                 musthave(BREAK, CONTIN);
1912         return(t);
1913 }
1914
1915 static char **
1916 pattern()
1917 {
1918         register int c, cf;
1919
1920         cf = CONTIN;
1921         do {
1922                 musthave(WORD, cf);
1923                 word(yylval.cp);
1924                 cf = 0;
1925         } while ((c = yylex(0)) == '|');
1926         peeksym = c;
1927         word(NOWORD);
1928         return(copyw());
1929 }
1930
1931 static char **
1932 wordlist()
1933 {
1934         register int c;
1935
1936         if ((c = yylex(0)) != IN) {
1937                 peeksym = c;
1938                 return((char **)NULL);
1939         }
1940         startl = 0;
1941         while ((c = yylex(0)) == WORD)
1942                 word(yylval.cp);
1943         word(NOWORD);
1944         peeksym = c;
1945         return(copyw());
1946 }
1947
1948 /*
1949  * supporting functions
1950  */
1951 static struct op *
1952 list(t1, t2)
1953 register struct op *t1, *t2;
1954 {
1955         if (t1 == NULL)
1956                 return(t2);
1957         if (t2 == NULL)
1958                 return(t1);
1959         return(block(TLIST, t1, t2, NOWORDS));
1960 }
1961
1962 static struct op *
1963 block(type, t1, t2, wp)
1964 int type;
1965 struct op *t1, *t2;
1966 char **wp;
1967 {
1968         register struct op *t;
1969
1970         t = newtp();
1971         t->type = type;
1972         t->left = t1;
1973         t->right = t2;
1974         t->words = wp;
1975         return(t);
1976 }
1977
1978 static int
1979 rlookup(n)
1980 register char *n;
1981 {
1982         register struct res *rp;
1983
1984         for (rp = restab; rp->r_name; rp++)
1985                 if (strcmp(rp->r_name, n) == 0)
1986                         return(rp->r_val);
1987         return(0);
1988 }
1989
1990 static struct op *
1991 newtp()
1992 {
1993         register struct op *t;
1994
1995         t = (struct op *)tree(sizeof(*t));
1996         t->type = 0;
1997         t->words = NULL;
1998         t->ioact = NULL;
1999         t->left = NULL;
2000         t->right = NULL;
2001         t->str = NULL;
2002         return(t);
2003 }
2004
2005 static struct op *
2006 namelist(t)
2007 register struct op *t;
2008 {
2009         if (iolist) {
2010                 iolist = addword((char *)NULL, iolist);
2011                 t->ioact = copyio();
2012         } else
2013                 t->ioact = NULL;
2014         if (t->type != TCOM) {
2015                 if (t->type != TPAREN && t->ioact != NULL) {
2016                         t = block(TPAREN, t, NOBLOCK, NOWORDS);
2017                         t->ioact = t->left->ioact;
2018                         t->left->ioact = NULL;
2019                 }
2020                 return(t);
2021         }
2022         word(NOWORD);
2023         t->words = copyw();
2024         return(t);
2025 }
2026
2027 static char **
2028 copyw()
2029 {
2030         register char **wd;
2031
2032         wd = getwords(wdlist);
2033         wdlist = 0;
2034         return(wd);
2035 }
2036
2037 static void
2038 word(cp)
2039 char *cp;
2040 {
2041         wdlist = addword(cp, wdlist);
2042 }
2043
2044 static struct ioword **
2045 copyio()
2046 {
2047         register struct ioword **iop;
2048
2049         iop = (struct ioword **) getwords(iolist);
2050         iolist = 0;
2051         return(iop);
2052 }
2053
2054 static struct ioword *
2055 io(u, f, cp)
2056 int u;
2057 int f;
2058 char *cp;
2059 {
2060         register struct ioword *iop;
2061
2062         iop = (struct ioword *) tree(sizeof(*iop));
2063         iop->io_unit = u;
2064         iop->io_flag = f;
2065         iop->io_name = cp;
2066         iolist = addword((char *)iop, iolist);
2067         return(iop);
2068 }
2069
2070 static void
2071 zzerr()
2072 {
2073         yyerror("syntax error");
2074 }
2075
2076 static void
2077 yyerror(s)
2078 char *s;
2079 {
2080         yynerrs++;
2081         if (interactive && e.iop <= iostack) {
2082                 multiline = 0;
2083                 while (eofc() == 0 && yylex(0) != '\n')
2084                         ;
2085         }
2086         err(s);
2087         fail();
2088 }
2089
2090 static int
2091 yylex(cf)
2092 int cf;
2093 {
2094         register int c, c1;
2095         int atstart;
2096
2097         if ((c = peeksym) > 0) {
2098                 peeksym = 0;
2099                 if (c == '\n')
2100                         startl = 1;
2101                 return(c);
2102         }
2103         nlseen = 0;
2104         e.linep = line;
2105         atstart = startl;
2106         startl = 0;
2107         yylval.i = 0;
2108
2109 loop:
2110         while ((c = my_getc(0)) == ' ' || c == '\t')
2111                 ;
2112         switch (c) {
2113         default:
2114                 if (any(c, "0123456789")) {
2115                         unget(c1 = my_getc(0));
2116                         if (c1 == '<' || c1 == '>') {
2117                                 iounit = c - '0';
2118                                 goto loop;
2119                         }
2120                         *e.linep++ = c;
2121                         c = c1;
2122                 }
2123                 break;
2124
2125         case '#':
2126                 while ((c = my_getc(0)) != 0 && c != '\n')
2127                         ;
2128                 unget(c);
2129                 goto loop;
2130
2131         case 0:
2132                 return(c);
2133
2134         case '$':
2135                 *e.linep++ = c;
2136                 if ((c = my_getc(0)) == '{') {
2137                         if ((c = collect(c, '}')) != '\0')
2138                                 return(c);
2139                         goto pack;
2140                 }
2141                 break;
2142
2143         case '`':
2144         case '\'':
2145         case '"':
2146                 if ((c = collect(c, c)) != '\0')
2147                         return(c);
2148                 goto pack;
2149
2150         case '|':
2151         case '&':
2152         case ';':
2153                 if ((c1 = dual(c)) != '\0') {
2154                         startl = 1;
2155                         return(c1);
2156                 }
2157                 startl = 1;
2158                 return(c);
2159         case '^':
2160                 startl = 1;
2161                 return('|');
2162         case '>':
2163         case '<':
2164                 diag(c);
2165                 return(c);
2166
2167         case '\n':
2168                 nlseen++;
2169                 gethere();
2170                 startl = 1;
2171                 if (multiline || cf & CONTIN) {
2172                         if (interactive && e.iop <= iostack) {
2173 #ifdef BB_FEATURE_COMMAND_EDITING
2174                         current_prompt=cprompt->value;
2175 #else
2176                         prs(cprompt->value);
2177 #endif
2178                         }
2179                         if (cf & CONTIN)
2180                                 goto loop;
2181                 }
2182                 return(c);
2183
2184         case '(':
2185         case ')':
2186                 startl = 1;
2187                 return(c);
2188         }
2189
2190         unget(c);
2191
2192 pack:
2193         while ((c = my_getc(0)) != 0 && !any(c, "`$ '\"\t;&<>()|^\n"))
2194                 if (e.linep >= elinep)
2195                         err("word too long");
2196                 else
2197                         *e.linep++ = c;
2198         unget(c);
2199         if(any(c, "\"'`$"))
2200                 goto loop;
2201         *e.linep++ = '\0';
2202         if (atstart && (c = rlookup(line))!=0) {
2203                 startl = 1;
2204                 return(c);
2205         }
2206         yylval.cp = strsave(line, areanum);
2207         return(WORD);
2208 }
2209
2210 static int
2211 collect(c, c1)
2212 register int c, c1;
2213 {
2214         char s[2];
2215
2216         *e.linep++ = c;
2217         while ((c = my_getc(c1)) != c1) {
2218                 if (c == 0) {
2219                         unget(c);
2220                         s[0] = c1;
2221                         s[1] = 0;
2222                         prs("no closing "); yyerror(s);
2223                         return(YYERRCODE);
2224                 }
2225                 if (interactive && c == '\n' && e.iop <= iostack) {
2226 #ifdef BB_FEATURE_COMMAND_EDITING
2227                     current_prompt=cprompt->value;
2228 #else
2229                     prs(cprompt->value);
2230 #endif
2231                 }
2232                 *e.linep++ = c;
2233         }
2234         *e.linep++ = c;
2235         return(0);
2236 }
2237
2238 static int
2239 dual(c)
2240 register int c;
2241 {
2242         char s[3];
2243         register char *cp = s;
2244
2245         *cp++ = c;
2246         *cp++ = my_getc(0);
2247         *cp = 0;
2248         if ((c = rlookup(s)) == 0)
2249                 unget(*--cp);
2250         return(c);
2251 }
2252
2253 static void
2254 diag(ec)
2255 register int ec;
2256 {
2257         register int c;
2258
2259         c = my_getc(0);
2260         if (c == '>' || c == '<') {
2261                 if (c != ec)
2262                         zzerr();
2263                 yylval.i = ec == '>'? IOWRITE|IOCAT: IOHERE;
2264                 c = my_getc(0);
2265         } else
2266                 yylval.i = ec == '>'? IOWRITE: IOREAD;
2267         if (c != '&' || yylval.i == IOHERE)
2268                 unget(c);
2269         else
2270                 yylval.i |= IODUP;
2271 }
2272
2273 static char *
2274 tree(size)
2275 unsigned size;
2276 {
2277         register char *t;
2278
2279         if ((t = getcell(size)) == NULL) {
2280                 prs("command line too complicated\n");
2281                 fail();
2282                 /* NOTREACHED */
2283         }
2284         return(t);
2285 }
2286
2287 /* VARARGS1 */
2288 /* ARGSUSED */
2289
2290 /* -------- exec.c -------- */
2291
2292 /*
2293  * execute tree
2294  */
2295
2296
2297 static int
2298 execute(t, pin, pout, act)
2299 register struct op *t;
2300 int *pin, *pout;
2301 int act;
2302 {
2303         register struct op *t1;
2304         volatile int i, rv, a;
2305         char *cp, **wp, **wp2;
2306         struct var *vp;
2307         struct brkcon bc;
2308
2309 #if __GNUC__
2310         /* Avoid longjmp clobbering */
2311         (void) &wp;
2312 #endif
2313
2314
2315         if (t == NULL)
2316                 return(0);
2317         rv = 0;
2318         a = areanum++;
2319         wp = (wp2 = t->words) != NULL
2320              ? eval(wp2, t->type == TCOM ? DOALL : DOALL & ~DOKEY)
2321              : NULL;
2322
2323         switch(t->type) {
2324         case TPAREN:
2325         case TCOM:
2326                 {
2327                         int child;
2328                         rv = forkexec(t, pin, pout, act, wp, &child);
2329                         if (child) {
2330                                 exstat = rv;
2331                                 leave();
2332                         }
2333                 }
2334                 break;
2335
2336         case TPIPE:
2337                 {
2338                     int pv[2];
2339                     if ((rv = openpipe(pv)) < 0)
2340                         break;
2341                     pv[0] = remap(pv[0]);
2342                     pv[1] = remap(pv[1]);
2343                     (void) execute(t->left, pin, pv, 0);
2344                     rv = execute(t->right, pv, pout, 0);
2345                 }
2346                 break;
2347
2348         case TLIST:
2349                 (void) execute(t->left, pin, pout, 0);
2350                 rv = execute(t->right, pin, pout, 0);
2351                 break;
2352
2353         case TASYNC:
2354         {
2355                 int hinteractive = interactive;
2356
2357                 i = vfork();
2358                 if (i != 0) {
2359                         interactive = hinteractive;
2360                         if (i != -1) {
2361                                 setval(lookup("!"), putn(i));
2362                                 if (pin != NULL)
2363                                         closepipe(pin);
2364                                 if (interactive) {
2365                                         prs(putn(i));
2366                                         prs("\n");
2367                                 }
2368                         } else
2369                                 rv = -1;
2370                         setstatus(rv);
2371                 } else {
2372                         signal(SIGINT, SIG_IGN);
2373                         signal(SIGQUIT, SIG_IGN);
2374                         if (interactive)
2375                                 signal(SIGTERM, SIG_DFL);
2376                         interactive = 0;
2377                         if (pin == NULL) {
2378                                 close(0);
2379                                 open("/dev/null", 0);
2380                         }
2381                         exit(execute(t->left, pin, pout, FEXEC));
2382                 }
2383         }
2384                 break;
2385
2386         case TOR:
2387         case TAND:
2388                 rv = execute(t->left, pin, pout, 0);
2389                 if ((t1 = t->right)!=NULL && (rv == 0) == (t->type == TAND))
2390                         rv = execute(t1, pin, pout, 0);
2391                 break;
2392
2393         case TFOR:
2394                 if (wp == NULL) {
2395                         wp = dolv+1;
2396                         if ((i = dolc) < 0)
2397                                 i = 0;
2398                 } else {
2399                         i = -1;
2400                         while (*wp++ != NULL)
2401                                 ;
2402                 }
2403                 vp = lookup(t->str);
2404                 while (setjmp(bc.brkpt))
2405                         if (isbreak)
2406                                 goto broken;
2407                 brkset(&bc);
2408                 for (t1 = t->left; i-- && *wp != NULL;) {
2409                         setval(vp, *wp++);
2410                         rv = execute(t1, pin, pout, 0);
2411                 }
2412                 brklist = brklist->nextlev;
2413                 break;
2414
2415         case TWHILE:
2416         case TUNTIL:
2417                 while (setjmp(bc.brkpt))
2418                         if (isbreak)
2419                                 goto broken;
2420                 brkset(&bc);
2421                 t1 = t->left;
2422                 while ((execute(t1, pin, pout, 0) == 0) == (t->type == TWHILE))
2423                         rv = execute(t->right, pin, pout, 0);
2424                 brklist = brklist->nextlev;
2425                 break;
2426
2427         case TIF:
2428         case TELIF:
2429                 if (t->right != NULL) {
2430                 rv = !execute(t->left, pin, pout, 0) ?
2431                         execute(t->right->left, pin, pout, 0):
2432                         execute(t->right->right, pin, pout, 0);
2433                 }
2434                 break;
2435
2436         case TCASE:
2437                 if ((cp = evalstr(t->str, DOSUB|DOTRIM)) == 0)
2438                         cp = "";
2439                 if ((t1 = findcase(t->left, cp)) != NULL)
2440                         rv = execute(t1, pin, pout, 0);
2441                 break;
2442
2443         case TBRACE:
2444 /*
2445                 if (iopp = t->ioact)
2446                         while (*iopp)
2447                                 if (iosetup(*iopp++, pin!=NULL, pout!=NULL)) {
2448                                         rv = -1;
2449                                         break;
2450                                 }
2451 */
2452                 if (rv >= 0 && (t1 = t->left))
2453                         rv = execute(t1, pin, pout, 0);
2454                 break;
2455         }
2456
2457 broken:
2458         t->words = wp2;
2459         isbreak = 0;
2460         freehere(areanum);
2461         freearea(areanum);
2462         areanum = a;
2463         if (interactive && intr) {
2464                 closeall();
2465                 fail();
2466         }
2467         if ((i = trapset) != 0) {
2468                 trapset = 0;
2469                 runtrap(i);
2470         }
2471         return(rv);
2472 }
2473
2474 static int
2475 forkexec( register struct op *t, int *pin, int *pout, int act, char **wp, int *pforked)
2476 {
2477         int i, rv;
2478         int (*shcom)() = NULL;
2479         register int f;
2480         char *cp = NULL;
2481         struct ioword **iopp;
2482         int resetsig;
2483         char **owp;
2484
2485         int *hpin = pin;
2486         int *hpout = pout;
2487         int hforked;
2488         char *hwp;
2489         int hinteractive;
2490         int hintr;
2491         struct brkcon * hbrklist;
2492         int hexecflg;
2493
2494 #if __GNUC__
2495         /* Avoid longjmp clobbering */
2496         (void) &pin;
2497         (void) &pout;
2498         (void) &wp;
2499         (void) &shcom;
2500         (void) &cp;
2501         (void) &resetsig;
2502         (void) &owp;
2503 #endif
2504
2505         owp = wp;
2506         resetsig = 0;
2507         *pforked = 0;
2508         rv = -1;        /* system-detected error */
2509         if (t->type == TCOM) {
2510                 while ((cp = *wp++) != NULL)
2511                         ;
2512                 cp = *wp;
2513
2514                 /* strip all initial assignments */
2515                 /* not correct wrt PATH=yyy command  etc */
2516                 if (flag['x'])
2517                         echo (cp ? wp: owp);
2518                 if (cp == NULL && t->ioact == NULL) {
2519                         while ((cp = *owp++) != NULL && assign(cp, COPYV))
2520                                 ;
2521                         return(setstatus(0));
2522                 }
2523                 else if (cp != NULL)
2524                         shcom = inbuilt(cp);
2525         }
2526         t->words = wp;
2527         f = act;
2528         if (shcom == NULL && (f & FEXEC) == 0) {
2529
2530                 hpin = pin;
2531                 hpout = pout;
2532                 hforked = *pforked;
2533                 hwp = *wp;
2534                 hinteractive = interactive;
2535                 hintr = intr;
2536                 hbrklist = brklist;
2537                 hexecflg = execflg;
2538
2539                 i = vfork();
2540                 if (i != 0) {
2541                         /* who wrote this crappy non vfork safe shit? */
2542                         pin = hpin;
2543                         pout = hpout;
2544                         *pforked = hforked;
2545                         *wp = hwp;
2546                         interactive = hinteractive;
2547                         intr = hintr;
2548                         brklist = hbrklist;
2549                         execflg = hexecflg;
2550
2551                         *pforked = 0;
2552                         if (i == -1)
2553                                 return(rv);
2554                         if (pin != NULL)
2555                                 closepipe(pin);
2556                         return(pout==NULL? setstatus(waitfor(i,0)): 0);
2557                 }
2558
2559                 if (interactive) {
2560                         signal(SIGINT, SIG_IGN);
2561                         signal(SIGQUIT, SIG_IGN);
2562                         resetsig = 1;
2563                 }
2564                 interactive = 0;
2565                 intr = 0;
2566                 (*pforked)++;
2567                 brklist = 0;
2568                 execflg = 0;
2569         }
2570         if (owp != NULL)
2571                 while ((cp = *owp++) != NULL && assign(cp, COPYV))
2572                         if (shcom == NULL)
2573                                 export(lookup(cp));
2574 #ifdef COMPIPE
2575         if ((pin != NULL || pout != NULL) && shcom != NULL && shcom != doexec) {
2576                 err("piping to/from shell builtins not yet done");
2577                 return(-1);
2578         }
2579 #endif
2580         if (pin != NULL) {
2581                 dup2(pin[0], 0);
2582                 closepipe(pin);
2583         }
2584         if (pout != NULL) {
2585                 dup2(pout[1], 1);
2586                 closepipe(pout);
2587         }
2588         if ((iopp = t->ioact) != NULL) {
2589                 if (shcom != NULL && shcom != doexec) {
2590                         prs(cp);
2591                         err(": cannot redirect shell command");
2592                         return(-1);
2593                 }
2594                 while (*iopp)
2595                         if (iosetup(*iopp++, pin!=NULL, pout!=NULL))
2596                                 return(rv);
2597         }
2598         if (shcom)
2599                 return(setstatus((*shcom)(t)));
2600         /* should use FIOCEXCL */
2601         for (i=FDBASE; i<NOFILE; i++)
2602                 close(i);
2603         if (resetsig) {
2604                 signal(SIGINT, SIG_DFL);
2605                 signal(SIGQUIT, SIG_DFL);
2606         }
2607         if (t->type == TPAREN)
2608                 exit(execute(t->left, NOPIPE, NOPIPE, FEXEC));
2609         if (wp[0] == NULL)
2610                 exit(0);
2611
2612         cp = rexecve(wp[0], wp, makenv());
2613         prs(wp[0]); prs(": "); warn(cp);
2614         if (!execflg)
2615                 trap[0] = NULL;
2616         leave();
2617         /* NOTREACHED */
2618         exit(1);
2619 }
2620
2621 /*
2622  * 0< 1> are ignored as required
2623  * within pipelines.
2624  */
2625 static int
2626 iosetup(iop, pipein, pipeout)
2627 register struct ioword *iop;
2628 int pipein, pipeout;
2629 {
2630         register int u = -1;
2631         char *cp=NULL, *msg;
2632
2633         if (iop->io_unit == IODEFAULT)  /* take default */
2634                 iop->io_unit = iop->io_flag&(IOREAD|IOHERE)? 0: 1;
2635         if (pipein && iop->io_unit == 0)
2636                 return(0);
2637         if (pipeout && iop->io_unit == 1)
2638                 return(0);
2639         msg = iop->io_flag&(IOREAD|IOHERE)? "open": "create";
2640         if ((iop->io_flag & IOHERE) == 0) {
2641                 cp = iop->io_name;
2642                 if ((cp = evalstr(cp, DOSUB|DOTRIM)) == NULL)
2643                         return(1);
2644         }
2645         if (iop->io_flag & IODUP) {
2646                 if (cp[1] || (!isdigit(*cp) && *cp != '-')) {
2647                         prs(cp);
2648                         err(": illegal >& argument");
2649                         return(1);
2650                 }
2651                 if (*cp == '-')
2652                         iop->io_flag = IOCLOSE;
2653                 iop->io_flag &= ~(IOREAD|IOWRITE);
2654         }
2655         switch (iop->io_flag) {
2656         case IOREAD:
2657                 u = open(cp, 0);
2658                 break;
2659
2660         case IOHERE:
2661         case IOHERE|IOXHERE:
2662                 u = herein(iop->io_name, iop->io_flag&IOXHERE);
2663                 cp = "here file";
2664                 break;
2665
2666         case IOWRITE|IOCAT:
2667                 if ((u = open(cp, 1)) >= 0) {
2668                         lseek(u, (long)0, 2);
2669                         break;
2670                 }
2671         case IOWRITE:
2672                 u = creat(cp, 0666);
2673                 break;
2674
2675         case IODUP:
2676                 u = dup2(*cp-'0', iop->io_unit);
2677                 break;
2678
2679         case IOCLOSE:
2680                 close(iop->io_unit);
2681                 return(0);
2682         }
2683         if (u < 0) {
2684                 prs(cp);
2685                 prs(": cannot ");
2686                 warn(msg);
2687                 return(1);
2688         } else {
2689                 if (u != iop->io_unit) {
2690                         dup2(u, iop->io_unit);
2691                         close(u);
2692                 }
2693         }
2694         return(0);
2695 }
2696
2697 static void
2698 echo(wp)
2699 register char **wp;
2700 {
2701         register int i;
2702
2703         prs("+");
2704         for (i=0; wp[i]; i++) {
2705                 if (i)
2706                         prs(" ");
2707                 prs(wp[i]);
2708         }
2709         prs("\n");
2710 }
2711
2712 static struct op **
2713 find1case(t, w)
2714 struct op *t;
2715 char *w;
2716 {
2717         register struct op *t1;
2718         struct op **tp;
2719         register char **wp, *cp;
2720
2721         if (t == NULL)
2722                 return((struct op **)NULL);
2723         if (t->type == TLIST) {
2724                 if ((tp = find1case(t->left, w)) != NULL)
2725                         return(tp);
2726                 t1 = t->right;  /* TPAT */
2727         } else
2728                 t1 = t;
2729         for (wp = t1->words; *wp;)
2730                 if ((cp = evalstr(*wp++, DOSUB)) && gmatch(w, cp))
2731                         return(&t1->left);
2732         return((struct op **)NULL);
2733 }
2734
2735 static struct op *
2736 findcase(t, w)
2737 struct op *t;
2738 char *w;
2739 {
2740         register struct op **tp;
2741
2742         return((tp = find1case(t, w)) != NULL? *tp: (struct op *)NULL);
2743 }
2744
2745 /*
2746  * Enter a new loop level (marked for break/continue).
2747  */
2748 static void
2749 brkset(bc)
2750 struct brkcon *bc;
2751 {
2752         bc->nextlev = brklist;
2753         brklist = bc;
2754 }
2755
2756 /*
2757  * Wait for the last process created.
2758  * Print a message for each process found
2759  * that was killed by a signal.
2760  * Ignore interrupt signals while waiting
2761  * unless `canintr' is true.
2762  */
2763 static int
2764 waitfor(lastpid, canintr)
2765 register int lastpid;
2766 int canintr;
2767 {
2768         register int pid, rv;
2769         int s;
2770         int oheedint = heedint;
2771
2772         heedint = 0;
2773         rv = 0;
2774         do {
2775                 pid = wait(&s);
2776                 if (pid == -1) {
2777                         if (errno != EINTR || canintr)
2778                                 break;
2779                 } else {
2780                         if ((rv = WAITSIG(s)) != 0) {
2781                                 if (rv < NSIGNAL) {
2782                                         if (signame[rv] != NULL) {
2783                                                 if (pid != lastpid) {
2784                                                         prn(pid);
2785                                                         prs(": ");
2786                                                 }
2787                                                 prs(signame[rv]);
2788                                         }
2789                                 } else {
2790                                         if (pid != lastpid) {
2791                                                 prn(pid);
2792                                                 prs(": ");
2793                                         }
2794                                         prs("Signal "); prn(rv); prs(" ");
2795                                 }
2796                                 if (WAITCORE(s))
2797                                         prs(" - core dumped");
2798                                 if (rv >= NSIGNAL || signame[rv])
2799                                         prs("\n");
2800                                 rv = -1;
2801                         } else
2802                                 rv = WAITVAL(s);
2803                 }
2804         } while (pid != lastpid);
2805         heedint = oheedint;
2806         if (intr) {
2807                 if (interactive) {
2808                         if (canintr)
2809                                 intr = 0;
2810                 } else {
2811                         if (exstat == 0) exstat = rv;
2812                         onintr(0);
2813                 }
2814         }
2815         return(rv);
2816 }
2817
2818 static int
2819 setstatus(s)
2820 register int s;
2821 {
2822         exstat = s;
2823         setval(lookup("?"), putn(s));
2824         return(s);
2825 }
2826
2827 /*
2828  * PATH-searching interface to execve.
2829  * If getenv("PATH") were kept up-to-date,
2830  * execvp might be used.
2831  */
2832 static char *
2833 rexecve(c, v, envp)
2834 char *c, **v, **envp;
2835 {
2836         register int i;
2837         register char *sp, *tp;
2838         int eacces = 0, asis = 0;
2839
2840 #ifdef BB_FEATURE_SH_STANDALONE_SHELL
2841         char *name = c;
2842 #ifdef BB_FEATURE_SH_APPLETS_ALWAYS_WIN
2843         name = get_last_path_component(name);
2844 #endif
2845         optind = 1;
2846         if (find_applet_by_name(name)) {
2847                 /* We have to exec here since we vforked.  Running
2848                  * run_applet_by_name() won't work and bad things
2849                  * will happen. */
2850                 execve("/proc/self/exe", v, envp);
2851                 execve("busybox", v, envp);
2852         }
2853 #endif
2854
2855         sp = any('/', c)? "": path->value;
2856         asis = *sp == '\0';
2857         while (asis || *sp != '\0') {
2858                 asis = 0;
2859                 tp = e.linep;
2860                 for (; *sp != '\0'; tp++)
2861                         if ((*tp = *sp++) == ':') {
2862                                 asis = *sp == '\0';
2863                                 break;
2864                         }
2865                 if (tp != e.linep)
2866                         *tp++ = '/';
2867                 for (i = 0; (*tp++ = c[i++]) != '\0';)
2868                         ;
2869
2870                 fprintf(stderr, "calling exec\n");
2871                 execve(e.linep, v, envp);
2872                 switch (errno) {
2873                 case ENOEXEC:
2874                         *v = e.linep;
2875                         tp = *--v;
2876                         *v = e.linep;
2877                         execve("/bin/sh", v, envp);
2878                         *v = tp;
2879                         return("no Shell");
2880
2881                 case ENOMEM:
2882                         return("program too big");
2883
2884                 case E2BIG:
2885                         return("argument list too long");
2886
2887                 case EACCES:
2888                         eacces++;
2889                         break;
2890                 }
2891         }
2892         return(errno==ENOENT ? "not found" : "cannot execute");
2893 }
2894
2895 /*
2896  * Run the command produced by generator `f'
2897  * applied to stream `arg'.
2898  */
2899 static int
2900 run(argp, f)
2901 struct ioarg *argp;
2902 int (*f)();
2903 {
2904         struct op *otree;
2905         struct wdblock *swdlist;
2906         struct wdblock *siolist;
2907         jmp_buf ev, rt;
2908         xint *ofail;
2909         int rv;
2910
2911 #if __GNUC__
2912         /* Avoid longjmp clobbering */
2913         (void) &rv;
2914 #endif
2915
2916         areanum++;
2917         swdlist = wdlist;
2918         siolist = iolist;
2919         otree = outtree;
2920         ofail = failpt;
2921         rv = -1;
2922         if (newenv(setjmp(errpt = ev)) == 0) {
2923                 wdlist = 0;
2924                 iolist = 0;
2925                 pushio(argp, f);
2926                 e.iobase = e.iop;
2927                 yynerrs = 0;
2928                 if (setjmp(failpt = rt) == 0 && yyparse() == 0)
2929                         rv = execute(outtree, NOPIPE, NOPIPE, 0);
2930                 quitenv();
2931         }
2932         wdlist = swdlist;
2933         iolist = siolist;
2934         failpt = ofail;
2935         outtree = otree;
2936         freearea(areanum--);
2937         return(rv);
2938 }
2939
2940 /* -------- do.c -------- */
2941
2942 /*
2943  * built-in commands: doX
2944  */
2945
2946 static int dohelp()
2947 {
2948         int col;
2949         const struct builtincmd *x;
2950
2951         printf("\nBuilt-in commands:\n");
2952         printf("-------------------\n");
2953
2954         for (col=0, x = builtincmds; x->builtinfunc != NULL; x++) {
2955                 if (!x->name)
2956                         continue;
2957                 col += printf("%s%s", ((col == 0) ? "\t" : " "), x->name);
2958                 if (col > 60) {
2959                         printf("\n");
2960                         col = 0;
2961                 }
2962         }
2963 #ifdef BB_FEATURE_SH_STANDALONE_SHELL
2964         {
2965                 int i;
2966                 const struct BB_applet *applet;
2967                 extern const struct BB_applet applets[];
2968                 extern const size_t NUM_APPLETS;
2969
2970                 for (i=0, applet = applets; i < NUM_APPLETS; applet++, i++) {
2971                         if (!applet->name)
2972                                 continue;
2973
2974                         col += printf("%s%s", ((col == 0) ? "\t" : " "),
2975                                         applet->name);
2976                         if (col > 60) {
2977                                 printf("\n");
2978                                 col = 0;
2979                         }
2980                 }
2981         }
2982 #endif
2983         printf("\n\n");
2984         return EXIT_SUCCESS;
2985 }
2986
2987
2988
2989 static int
2990 dolabel()
2991 {
2992         return(0);
2993 }
2994
2995 static int
2996 dochdir(t)
2997 register struct op *t;
2998 {
2999         register char *cp, *er;
3000
3001         if ((cp = t->words[1]) == NULL && (cp = homedir->value) == NULL)
3002                 er = ": no home directory";
3003         else if(chdir(cp) < 0)
3004                 er = ": bad directory";
3005         else
3006                 return(0);
3007         prs(cp != NULL? cp: "cd");
3008         err(er);
3009         return(1);
3010 }
3011
3012 static int
3013 doshift(t)
3014 register struct op *t;
3015 {
3016         register int n;
3017
3018         n = t->words[1]? getn(t->words[1]): 1;
3019         if(dolc < n) {
3020                 err("nothing to shift");
3021                 return(1);
3022         }
3023         dolv[n] = dolv[0];
3024         dolv += n;
3025         dolc -= n;
3026         setval(lookup("#"), putn(dolc));
3027         return(0);
3028 }
3029
3030 /*
3031  * execute login and newgrp directly
3032  */
3033 static int
3034 dologin(t)
3035 struct op *t;
3036 {
3037         register char *cp;
3038
3039         if (interactive) {
3040                 signal(SIGINT, SIG_DFL);
3041                 signal(SIGQUIT, SIG_DFL);
3042         }
3043         cp = rexecve(t->words[0], t->words, makenv());
3044         prs(t->words[0]); prs(": "); err(cp);
3045         return(1);
3046 }
3047
3048 static int
3049 doumask(t)
3050 register struct op *t;
3051 {
3052         register int i, n;
3053         register char *cp;
3054
3055         if ((cp = t->words[1]) == NULL) {
3056                 i = umask(0);
3057                 umask(i);
3058                 for (n=3*4; (n-=3) >= 0;)
3059                         putc('0'+((i>>n)&07), stderr);
3060                 putc('\n', stderr);
3061         } else {
3062                 for (n=0; *cp>='0' && *cp<='9'; cp++)
3063                         n = n*8 + (*cp-'0');
3064                 umask(n);
3065         }
3066         return(0);
3067 }
3068
3069 static int
3070 doexec(t)
3071 register struct op *t;
3072 {
3073         register int i;
3074         jmp_buf ex;
3075         xint *ofail;
3076
3077         t->ioact = NULL;
3078         for(i = 0; (t->words[i]=t->words[i+1]) != NULL; i++)
3079                 ;
3080         if (i == 0)
3081                 return(1);
3082         execflg = 1;
3083         ofail = failpt;
3084         if (setjmp(failpt = ex) == 0)
3085                 execute(t, NOPIPE, NOPIPE, FEXEC);
3086         failpt = ofail;
3087         execflg = 0;
3088         return(1);
3089 }
3090
3091 static int
3092 dodot(t)
3093 struct op *t;
3094 {
3095         register int i;
3096         register char *sp, *tp;
3097         char *cp;
3098
3099         if ((cp = t->words[1]) == NULL)
3100                 return(0);
3101         sp = any('/', cp)? ":": path->value;
3102         while (*sp) {
3103                 tp = e.linep;
3104                 while (*sp && (*tp = *sp++) != ':')
3105                         tp++;
3106                 if (tp != e.linep)
3107                         *tp++ = '/';
3108                 for (i = 0; (*tp++ = cp[i++]) != '\0';)
3109                         ;
3110                 if ((i = open(e.linep, 0)) >= 0) {
3111                         exstat = 0;
3112                         next(remap(i));
3113                         return(exstat);
3114                 }
3115         }
3116         prs(cp);
3117         err(": not found");
3118         return(-1);
3119 }
3120
3121 static int
3122 dowait(t)
3123 struct op *t;
3124 {
3125         register int i;
3126         register char *cp;
3127
3128         if ((cp = t->words[1]) != NULL) {
3129                 i = getn(cp);
3130                 if (i == 0)
3131                         return(0);
3132         } else
3133                 i = -1;
3134         setstatus(waitfor(i, 1));
3135         return(0);
3136 }
3137
3138 static int
3139 doread(t)
3140 struct op *t;
3141 {
3142         register char *cp, **wp;
3143         register int nb = 0;
3144         register int  nl = 0;
3145
3146         if (t->words[1] == NULL) {
3147                 err("Usage: read name ...");
3148                 return(1);
3149         }
3150         for (wp = t->words+1; *wp; wp++) {
3151                 for (cp = e.linep; !nl && cp < elinep-1; cp++)
3152                         if ((nb = read(0, cp, sizeof(*cp))) != sizeof(*cp) ||
3153                             (nl = (*cp == '\n')) ||
3154                             (wp[1] && any(*cp, ifs->value)))
3155                                 break;
3156                 *cp = 0;
3157                 if (nb <= 0)
3158                         break;
3159                 setval(lookup(*wp), e.linep);
3160         }
3161         return(nb <= 0);
3162 }
3163
3164 static int
3165 doeval(t)
3166 register struct op *t;
3167 {
3168         return(RUN(awordlist, t->words+1, wdchar));
3169 }
3170
3171 static int
3172 dotrap(t)
3173 register struct op *t;
3174 {
3175         register int  n, i;
3176         register int  resetsig;
3177
3178         if (t->words[1] == NULL) {
3179                 for (i=0; i<=_NSIG; i++)
3180                         if (trap[i]) {
3181                                 prn(i);
3182                                 prs(": ");
3183                                 prs(trap[i]);
3184                                 prs("\n");
3185                         }
3186                 return(0);
3187         }
3188         resetsig = isdigit(*t->words[1]);
3189         for (i = resetsig ? 1 : 2; t->words[i] != NULL; ++i) {
3190                 n = getsig(t->words[i]);
3191                 freecell(trap[n]);
3192                 trap[n] = 0;
3193                 if (!resetsig) {
3194                         if (*t->words[1] != '\0') {
3195                                 trap[n] = strsave(t->words[1], 0);
3196                                 setsig(n, sig);
3197                         } else
3198                                 setsig(n, SIG_IGN);
3199                 } else {
3200                         if (interactive)
3201                                 if (n == SIGINT)
3202                                         setsig(n, onintr);
3203                                 else
3204                                         setsig(n, n == SIGQUIT ? SIG_IGN
3205                                                                : SIG_DFL);
3206                         else
3207                                 setsig(n, SIG_DFL);
3208                 }
3209         }
3210         return(0);
3211 }
3212
3213 static int
3214 getsig(s)
3215 char *s;
3216 {
3217         register int n;
3218
3219         if ((n = getn(s)) < 0 || n > _NSIG) {
3220                 err("trap: bad signal number");
3221                 n = 0;
3222         }
3223         return(n);
3224 }
3225
3226 static void
3227 setsig( register int n, void (*f)(int))
3228 {
3229         if (n == 0)
3230                 return;
3231         if (signal(n, SIG_IGN) != SIG_IGN || ourtrap[n]) {
3232                 ourtrap[n] = 1;
3233                 signal(n, f);
3234         }
3235 }
3236
3237 static int
3238 getn(as)
3239 char *as;
3240 {
3241         register char *s;
3242         register int n, m;
3243
3244         s = as;
3245         m = 1;
3246         if (*s == '-') {
3247                 m = -1;
3248                 s++;
3249         }
3250         for (n = 0; isdigit(*s); s++)
3251                 n = (n*10) + (*s-'0');
3252         if (*s) {
3253                 prs(as);
3254                 err(": bad number");
3255         }
3256         return(n*m);
3257 }
3258
3259 static int
3260 dobreak(t)
3261 struct op *t;
3262 {
3263         return(brkcontin(t->words[1], 1));
3264 }
3265
3266 static int
3267 docontinue(t)
3268 struct op *t;
3269 {
3270         return(brkcontin(t->words[1], 0));
3271 }
3272
3273 static int
3274 brkcontin(cp, val)
3275 register char *cp;
3276 int val;
3277 {
3278         register struct brkcon *bc;
3279         register int nl;
3280
3281         nl = cp == NULL? 1: getn(cp);
3282         if (nl <= 0)
3283                 nl = 999;
3284         do {
3285                 if ((bc = brklist) == NULL)
3286                         break;
3287                 brklist = bc->nextlev;
3288         } while (--nl);
3289         if (nl) {
3290                 err("bad break/continue level");
3291                 return(1);
3292         }
3293         isbreak = val;
3294         longjmp(bc->brkpt, 1);
3295         /* NOTREACHED */
3296 }
3297
3298 static int
3299 doexit(t)
3300 struct op *t;
3301 {
3302         register char *cp;
3303
3304         execflg = 0;
3305         if ((cp = t->words[1]) != NULL)
3306                 setstatus(getn(cp));
3307         leave();
3308         /* NOTREACHED */
3309         return(0);
3310 }
3311
3312 static int
3313 doexport(t)
3314 struct op *t;
3315 {
3316         rdexp(t->words+1, export, EXPORT);
3317         return(0);
3318 }
3319
3320 static int
3321 doreadonly(t)
3322 struct op *t;
3323 {
3324         rdexp(t->words+1, ronly, RONLY);
3325         return(0);
3326 }
3327
3328 static void
3329 rdexp(wp, f, key)
3330 register char **wp;
3331 void (*f)();
3332 int key;
3333 {
3334         if (*wp != NULL) {
3335                 for (; *wp != NULL; wp++)
3336                         if (checkname(*wp))
3337                                 (*f)(lookup(*wp));
3338                         else
3339                                 badid(*wp);
3340         } else
3341                 putvlist(key, 1);
3342 }
3343
3344 static void
3345 badid(s)
3346 register char *s;
3347 {
3348         prs(s);
3349         err(": bad identifier");
3350 }
3351
3352 static int
3353 doset(t)
3354 register struct op *t;
3355 {
3356         register struct var *vp;
3357         register char *cp;
3358         register int n;
3359
3360         if ((cp = t->words[1]) == NULL) {
3361                 for (vp = vlist; vp; vp = vp->next)
3362                         varput(vp->name, 1);
3363                 return(0);
3364         }
3365         if (*cp == '-') {
3366                 /* bad: t->words++; */
3367                 for(n = 0; (t->words[n]=t->words[n+1]) != NULL; n++)
3368                         ;
3369                 if (*++cp == 0)
3370                         flag['x'] = flag['v'] = 0;
3371                 else
3372                         for (; *cp; cp++)
3373                                 switch (*cp) {
3374                                 case 'e':
3375                                         if (!interactive)
3376                                                 flag['e']++;
3377                                         break;
3378
3379                                 default:
3380                                         if (*cp>='a' && *cp<='z')
3381                                                 flag[(int)*cp]++;
3382                                         break;
3383                                 }
3384                 setdash();
3385         }
3386         if (t->words[1]) {
3387                 t->words[0] = dolv[0];
3388                 for (n=1; t->words[n]; n++)
3389                         setarea((char *)t->words[n], 0);
3390                 dolc = n-1;
3391                 dolv = t->words;
3392                 setval(lookup("#"), putn(dolc));
3393                 setarea((char *)(dolv-1), 0);
3394         }
3395         return(0);
3396 }
3397
3398 static void
3399 varput(s, out)
3400 register char *s;
3401 int out;
3402 {
3403         if (isalnum(*s)) {
3404                 write(out, s, strlen(s));
3405                 write(out, "\n", 1);
3406         }
3407 }
3408
3409
3410 /*
3411  * Copyright (c) 1999 Herbert Xu <herbert@debian.org>
3412  * This file contains code for the times builtin.
3413  */
3414 static int dotimes ()
3415 {
3416         struct tms buf;
3417         long int clk_tck = sysconf(_SC_CLK_TCK);
3418
3419         times(&buf);
3420         printf("%dm%fs %dm%fs\n%dm%fs %dm%fs\n",
3421                (int) (buf.tms_utime / clk_tck / 60),
3422                ((double) buf.tms_utime) / clk_tck,
3423                (int) (buf.tms_stime / clk_tck / 60),
3424                ((double) buf.tms_stime) / clk_tck,
3425                (int) (buf.tms_cutime / clk_tck / 60),
3426                ((double) buf.tms_cutime) / clk_tck,
3427                (int) (buf.tms_cstime / clk_tck / 60),
3428                ((double) buf.tms_cstime) / clk_tck);
3429         return 0;
3430 }
3431
3432
3433 static int (*inbuilt(char *s))()
3434 {
3435         const struct builtincmd *bp;
3436
3437         for (bp = builtincmds; bp->name != NULL; bp++)
3438                 if (strcmp(bp->name, s) == 0)
3439                         return(bp->builtinfunc);
3440
3441         return((int(*)())NULL);
3442 }
3443
3444 /* -------- eval.c -------- */
3445
3446 /*
3447  * ${}
3448  * `command`
3449  * blank interpretation
3450  * quoting
3451  * glob
3452  */
3453
3454 static char ** eval( char **ap, int f)
3455 {
3456         struct wdblock *wb;
3457         char **wp;
3458         char **wf;
3459         jmp_buf ev;
3460
3461 #if __GNUC__
3462         /* Avoid longjmp clobbering */
3463         (void) &wp;
3464         (void) &ap;
3465 #endif
3466         wp = NULL;
3467         wb = NULL;
3468         wf = NULL;
3469         if (newenv(setjmp(errpt = ev)) == 0) {
3470                 while (*ap && isassign(*ap))
3471                         expand(*ap++, &wb, f & ~DOGLOB);
3472                 if (flag['k']) {
3473                         for (wf = ap; *wf; wf++) {
3474                                 if (isassign(*wf))
3475                                         expand(*wf, &wb, f & ~DOGLOB);
3476                         }
3477                 }
3478                 for (wb = addword((char *)0, wb); *ap; ap++) {
3479                         if (!flag['k'] || !isassign(*ap))
3480                                 expand(*ap, &wb, f & ~DOKEY);
3481                 }
3482                 wb = addword((char *)0, wb);
3483                 wp = getwords(wb);
3484                 quitenv();
3485         } else
3486                 gflg = 1;
3487         return(gflg? (char **)NULL: wp);
3488 }
3489
3490 /*
3491  * Make the exported environment from the exported
3492  * names in the dictionary. Keyword assignments
3493  * will already have been done.
3494  */
3495 static char **
3496 makenv()
3497
3498 {
3499         register struct wdblock *wb;
3500         register struct var *vp;
3501
3502         wb = NULL;
3503         for (vp = vlist; vp; vp = vp->next)
3504                 if (vp->status & EXPORT)
3505                         wb = addword(vp->name, wb);
3506         wb = addword((char *)0, wb);
3507         return(getwords(wb));
3508 }
3509
3510 static char *
3511 evalstr(cp, f)
3512 register char *cp;
3513 int f;
3514 {
3515         struct wdblock *wb;
3516
3517         wb = NULL;
3518         if (expand(cp, &wb, f)) {
3519                 if (wb == NULL || wb->w_nword == 0 || (cp = wb->w_words[0]) == NULL)
3520                         cp = "";
3521                 DELETE(wb);
3522         } else
3523                 cp = NULL;
3524         return(cp);
3525 }
3526
3527 static int
3528 expand( char *cp, register struct wdblock **wbp, int f)
3529 {
3530         jmp_buf ev;
3531
3532 #if __GNUC__
3533         /* Avoid longjmp clobbering */
3534         (void) &cp;
3535 #endif
3536         gflg = 0;
3537         if (cp == NULL)
3538                 return(0);
3539         if (!anys("$`'\"", cp) &&
3540             !anys(ifs->value, cp) &&
3541             ((f&DOGLOB)==0 || !anys("[*?", cp))) {
3542                 cp = strsave(cp, areanum);
3543                 if (f & DOTRIM)
3544                         unquote(cp);
3545                 *wbp = addword(cp, *wbp);
3546                 return(1);
3547         }
3548         if (newenv(setjmp(errpt = ev)) == 0) {
3549                 PUSHIO(aword, cp, strchar);
3550                 e.iobase = e.iop;
3551                 while ((cp = blank(f)) && gflg == 0) {
3552                         e.linep = cp;
3553                         cp = strsave(cp, areanum);
3554                         if ((f&DOGLOB) == 0) {
3555                                 if (f & DOTRIM)
3556                                         unquote(cp);
3557                                 *wbp = addword(cp, *wbp);
3558                         } else
3559                                 *wbp = glob(cp, *wbp);
3560                 }
3561                 quitenv();
3562         } else
3563                 gflg = 1;
3564         return(gflg == 0);
3565 }
3566
3567 /*
3568  * Blank interpretation and quoting
3569  */
3570 static char *
3571 blank(f)
3572 int f;
3573 {
3574         register int c, c1;
3575         register char *sp;
3576         int scanequals, foundequals;
3577
3578         sp = e.linep;
3579         scanequals = f & DOKEY;
3580         foundequals = 0;
3581
3582 loop:
3583         switch (c = subgetc('"', foundequals)) {
3584         case 0:
3585                 if (sp == e.linep)
3586                         return(0);
3587                 *e.linep++ = 0;
3588                 return(sp);
3589
3590         default:
3591                 if (f & DOBLANK && any(c, ifs->value))
3592                         goto loop;
3593                 break;
3594
3595         case '"':
3596         case '\'':
3597                 scanequals = 0;
3598                 if (INSUB())
3599                         break;
3600                 for (c1 = c; (c = subgetc(c1, 1)) != c1;) {
3601                         if (c == 0)
3602                                 break;
3603                         if (c == '\'' || !any(c, "$`\""))
3604                                 c |= QUOTE;
3605                         *e.linep++ = c;
3606                 }
3607                 c = 0;
3608         }
3609         unget(c);
3610         if (!isalpha(c))
3611                 scanequals = 0;
3612         for (;;) {
3613                 c = subgetc('"', foundequals);
3614                 if (c == 0 ||
3615                     f & (DOBLANK && any(c, ifs->value)) ||
3616                     (!INSUB() && any(c, "\"'"))) {
3617                         scanequals = 0;
3618                         unget(c);
3619                         if (any(c, "\"'"))
3620                                 goto loop;
3621                         break;
3622                 }
3623                 if (scanequals) {
3624                         if (c == '=') {
3625                                 foundequals = 1;
3626                                 scanequals  = 0;
3627                         }
3628                         else if (!isalnum(c))
3629                                 scanequals = 0;
3630                 }
3631                 *e.linep++ = c;
3632         }
3633         *e.linep++ = 0;
3634         return(sp);
3635 }
3636
3637 /*
3638  * Get characters, substituting for ` and $
3639  */
3640 static int
3641 subgetc(ec, quoted)
3642 register int ec;
3643 int quoted;
3644 {
3645         register char c;
3646
3647 again:
3648         c = my_getc(ec);
3649         if (!INSUB() && ec != '\'') {
3650                 if (c == '`') {
3651                         if (grave(quoted) == 0)
3652                                 return(0);
3653                         e.iop->task = XGRAVE;
3654                         goto again;
3655                 }
3656                 if (c == '$' && (c = dollar(quoted)) == 0) {
3657                         e.iop->task = XDOLL;
3658                         goto again;
3659                 }
3660         }
3661         return(c);
3662 }
3663
3664 /*
3665  * Prepare to generate the string returned by ${} substitution.
3666  */
3667 static int
3668 dollar(quoted)
3669 int quoted;
3670 {
3671         int otask;
3672         struct io *oiop;
3673         char *dolp;
3674         register char *s, c, *cp=NULL;
3675         struct var *vp;
3676
3677         c = readc();
3678         s = e.linep;
3679         if (c != '{') {
3680                 *e.linep++ = c;
3681                 if (isalpha(c)) {
3682                         while ((c = readc())!=0 && isalnum(c))
3683                                 if (e.linep < elinep)
3684                                         *e.linep++ = c;
3685                         unget(c);
3686                 }
3687                 c = 0;
3688         } else {
3689                 oiop = e.iop;
3690                 otask = e.iop->task;
3691                 e.iop->task = XOTHER;
3692                 while ((c = subgetc('"', 0))!=0 && c!='}' && c!='\n')
3693                         if (e.linep < elinep)
3694                                 *e.linep++ = c;
3695                 if (oiop == e.iop)
3696                         e.iop->task = otask;
3697                 if (c != '}') {
3698                         err("unclosed ${");
3699                         gflg++;
3700                         return(c);
3701                 }
3702         }
3703         if (e.linep >= elinep) {
3704                 err("string in ${} too long");
3705                 gflg++;
3706                 e.linep -= 10;
3707         }
3708         *e.linep = 0;
3709         if (*s)
3710                 for (cp = s+1; *cp; cp++)
3711                         if (any(*cp, "=-+?")) {
3712                                 c = *cp;
3713                                 *cp++ = 0;
3714                                 break;
3715                         }
3716         if (s[1] == 0 && (*s == '*' || *s == '@')) {
3717                 if (dolc > 1) {
3718                         /* currently this does not distinguish $* and $@ */
3719                         /* should check dollar */
3720                         e.linep = s;
3721                         PUSHIO(awordlist, dolv+1, dolchar);
3722                         return(0);
3723                 } else {        /* trap the nasty ${=} */
3724                         s[0] = '1';
3725                         s[1] = 0;
3726                 }
3727         }
3728         vp = lookup(s);
3729         if ((dolp = vp->value) == null) {
3730                 switch (c) {
3731                 case '=':
3732                         if (isdigit(*s)) {
3733                                 err("cannot use ${...=...} with $n");
3734                                 gflg++;
3735                                 break;
3736                         }
3737                         setval(vp, cp);
3738                         dolp = vp->value;
3739                         break;
3740
3741                 case '-':
3742                         dolp = strsave(cp, areanum);
3743                         break;
3744
3745                 case '?':
3746                         if (*cp == 0) {
3747                                 prs("missing value for ");
3748                                 err(s);
3749                         } else
3750                                 err(cp);
3751                         gflg++;
3752                         break;
3753                 }
3754         } else if (c == '+')
3755                 dolp = strsave(cp, areanum);
3756         if (flag['u'] && dolp == null) {
3757                 prs("unset variable: ");
3758                 err(s);
3759                 gflg++;
3760         }
3761         e.linep = s;
3762         PUSHIO(aword, dolp, quoted ? qstrchar : strchar);
3763         return(0);
3764 }
3765
3766 /*
3767  * Run the command in `...` and read its output.
3768  */
3769 static int
3770 grave(quoted)
3771 int quoted;
3772 {
3773         register int i;
3774         char *cp;
3775         int pf[2];
3776
3777 #if __GNUC__
3778         /* Avoid longjmp clobbering */
3779         (void) &cp;
3780 #endif
3781         for (cp = e.iop->argp->aword; *cp != '`'; cp++)
3782                 if (*cp == 0) {
3783                         err("no closing `");
3784                         return(0);
3785                 }
3786         if (openpipe(pf) < 0)
3787                 return(0);
3788         if ((i = vfork()) == -1) {
3789                 closepipe(pf);
3790                 err("try again");
3791                 return(0);
3792         }
3793         if (i != 0) {
3794                 e.iop->argp->aword = ++cp;
3795                 close(pf[1]);
3796                 PUSHIO(afile, remap(pf[0]), quoted? qgravechar: gravechar);
3797                 return(1);
3798         }
3799         *cp = 0;
3800         /* allow trapped signals */
3801         for (i=0; i<=_NSIG; i++)
3802                 if (ourtrap[i] && signal(i, SIG_IGN) != SIG_IGN)
3803                         signal(i, SIG_DFL);
3804         dup2(pf[1], 1);
3805         closepipe(pf);
3806         flag['e'] = 0;
3807         flag['v'] = 0;
3808         flag['n'] = 0;
3809         cp = strsave(e.iop->argp->aword, 0);
3810         areanum = 1;
3811         freehere(areanum);
3812         freearea(areanum);      /* free old space */
3813         e.oenv = NULL;
3814         e.iop = (e.iobase = iostack) - 1;
3815         unquote(cp);
3816         interactive = 0;
3817         PUSHIO(aword, cp, nlchar);
3818         onecommand();
3819         exit(1);
3820 }
3821
3822 static char *
3823 unquote(as)
3824 register char *as;
3825 {
3826         register char *s;
3827
3828         if ((s = as) != NULL)
3829                 while (*s)
3830                         *s++ &= ~QUOTE;
3831         return(as);
3832 }
3833
3834 /* -------- glob.c -------- */
3835
3836 /*
3837  * glob
3838  */
3839
3840 #define scopy(x) strsave((x), areanum)
3841 #define BLKSIZ  512
3842 #define NDENT   ((BLKSIZ+sizeof(struct dirent)-1)/sizeof(struct dirent))
3843
3844 static  struct wdblock  *cl, *nl;
3845 static  char    spcl[] = "[?*";
3846
3847 static struct wdblock *
3848 glob(cp, wb)
3849 char *cp;
3850 struct wdblock *wb;
3851 {
3852         register int i;
3853         register char *pp;
3854
3855         if (cp == 0)
3856                 return(wb);
3857         i = 0;
3858         for (pp = cp; *pp; pp++)
3859                 if (any(*pp, spcl))
3860                         i++;
3861                 else if (!any(*pp & ~QUOTE, spcl))
3862                         *pp &= ~QUOTE;
3863         if (i != 0) {
3864                 for (cl = addword(scopy(cp), (struct wdblock *)0); anyspcl(cl); cl = nl) {
3865                         nl = newword(cl->w_nword*2);
3866                         for(i=0; i<cl->w_nword; i++) { /* for each argument */
3867                                 for (pp = cl->w_words[i]; *pp; pp++)
3868                                         if (any(*pp, spcl)) {
3869                                                 globname(cl->w_words[i], pp);
3870                                                 break;
3871                                         }
3872                                 if (*pp == '\0')
3873                                         nl = addword(scopy(cl->w_words[i]), nl);
3874                         }
3875                         for(i=0; i<cl->w_nword; i++)
3876                                 DELETE(cl->w_words[i]);
3877                         DELETE(cl);
3878                 }
3879                 for(i=0; i<cl->w_nword; i++)
3880                         unquote(cl->w_words[i]);
3881                 glob0((char *)cl->w_words, cl->w_nword, sizeof(char *), xstrcmp);
3882                 if (cl->w_nword) {
3883                         for (i=0; i<cl->w_nword; i++)
3884                                 wb = addword(cl->w_words[i], wb);
3885                         DELETE(cl);
3886                         return(wb);
3887                 }
3888         }
3889         wb = addword(unquote(cp), wb);
3890         return(wb);
3891 }
3892
3893 static void
3894 globname(we, pp)
3895 char *we;
3896 register char *pp;
3897 {
3898         register char *np, *cp;
3899         char *name, *gp, *dp;
3900         int k;
3901         DIR *dirp;
3902         struct dirent *de;
3903         char dname[NAME_MAX+1];
3904         struct stat dbuf;
3905
3906         for (np = we; np != pp; pp--)
3907                 if (pp[-1] == '/')
3908                         break;
3909         for (dp = cp = space((int)(pp-np)+3); np < pp;)
3910                 *cp++ = *np++;
3911         *cp++ = '.';
3912         *cp = '\0';
3913         for (gp = cp = space(strlen(pp)+1); *np && *np != '/';)
3914                 *cp++ = *np++;
3915         *cp = '\0';
3916         dirp = opendir(dp);
3917         if (dirp == 0) {
3918                 DELETE(dp);
3919                 DELETE(gp);
3920                 return;
3921         }
3922         dname[NAME_MAX] = '\0';
3923         while ((de=readdir(dirp))!=NULL) {
3924                 /* XXX Hmmm... What this could be? (abial) */
3925                 /*
3926                 if (ent[j].d_ino == 0)
3927                         continue;
3928                 */
3929                 strncpy(dname, de->d_name, NAME_MAX);
3930                         if (dname[0] == '.')
3931                                 if (*gp != '.')
3932                                         continue;
3933                         for(k=0; k<NAME_MAX; k++)
3934                                 if (any(dname[k], spcl))
3935                                         dname[k] |= QUOTE;
3936                         if (gmatch(dname, gp)) {
3937                                 name = generate(we, pp, dname, np);
3938                                 if (*np && !anys(np, spcl)) {
3939                                         if (stat(name,&dbuf)) {
3940                                                 DELETE(name);
3941                                                 continue;
3942                                         }
3943                                 }
3944                                 nl = addword(name, nl);
3945                         }
3946         }
3947         closedir(dirp);
3948         DELETE(dp);
3949         DELETE(gp);
3950 }
3951
3952 /*
3953  * generate a pathname as below.
3954  * start..end1 / middle end
3955  * the slashes come for free
3956  */
3957 static char *
3958 generate(start1, end1, middle, end)
3959 char *start1;
3960 register char *end1;
3961 char *middle, *end;
3962 {
3963         char *p;
3964         register char *op, *xp;
3965
3966         p = op = space((int)(end1-start1)+strlen(middle)+strlen(end)+2);
3967         for (xp = start1; xp != end1;)
3968                 *op++ = *xp++;
3969         for (xp = middle; (*op++ = *xp++) != '\0';)
3970                 ;
3971         op--;
3972         for (xp = end; (*op++ = *xp++) != '\0';)
3973                 ;
3974         return(p);
3975 }
3976
3977 static int
3978 anyspcl(wb)
3979 register struct wdblock *wb;
3980 {
3981         register int i;
3982         register char **wd;
3983
3984         wd = wb->w_words;
3985         for (i=0; i<wb->w_nword; i++)
3986                 if (anys(spcl, *wd++))
3987                         return(1);
3988         return(0);
3989 }
3990
3991 static int
3992 xstrcmp(p1, p2)
3993 char *p1, *p2;
3994 {
3995         return(strcmp(*(char **)p1, *(char **)p2));
3996 }
3997
3998 /* -------- word.c -------- */
3999
4000 static struct wdblock *
4001 newword(nw)
4002 register int nw;
4003 {
4004         register struct wdblock *wb;
4005
4006         wb = (struct wdblock *) space(sizeof(*wb) + nw*sizeof(char *));
4007         wb->w_bsize = nw;
4008         wb->w_nword = 0;
4009         return(wb);
4010 }
4011
4012 static struct wdblock *
4013 addword(wd, wb)
4014 char *wd;
4015 register struct wdblock *wb;
4016 {
4017         register struct wdblock *wb2;
4018         register int nw;
4019
4020         if (wb == NULL)
4021                 wb = newword(NSTART);
4022         if ((nw = wb->w_nword) >= wb->w_bsize) {
4023                 wb2 = newword(nw * 2);
4024                 memcpy((char *)wb2->w_words, (char *)wb->w_words, nw*sizeof(char *));
4025                 wb2->w_nword = nw;
4026                 DELETE(wb);
4027                 wb = wb2;
4028         }
4029         wb->w_words[wb->w_nword++] = wd;
4030         return(wb);
4031 }
4032 static
4033 char **
4034 getwords(wb)
4035 register struct wdblock *wb;
4036 {
4037         register char **wd;
4038         register int nb;
4039
4040         if (wb == NULL)
4041                 return((char **)NULL);
4042         if (wb->w_nword == 0) {
4043                 DELETE(wb);
4044                 return((char **)NULL);
4045         }
4046         wd = (char **) space(nb = sizeof(*wd) * wb->w_nword);
4047         memcpy((char *)wd, (char *)wb->w_words, nb);
4048         DELETE(wb);     /* perhaps should done by caller */
4049         return(wd);
4050 }
4051
4052 int (*func)(char *, char *);
4053 int     globv;
4054
4055 static void
4056 glob0(a0, a1, a2, a3)
4057 char *a0;
4058 unsigned a1;
4059 int a2;
4060 int (*a3) (char *, char *);
4061 {
4062         func = a3;
4063         globv = a2;
4064         glob1(a0, a0 + a1 * a2);
4065 }
4066
4067 static void
4068 glob1(base, lim)
4069 char *base, *lim;
4070 {
4071         register char *i, *j;
4072         int v2;
4073         char *lptr, *hptr;
4074         int c;
4075         unsigned n;
4076
4077
4078         v2 = globv;
4079
4080 top:
4081         if ((n=(int)(lim-base)) <= v2)
4082                 return;
4083         n = v2 * (n / (2*v2));
4084         hptr = lptr = base+n;
4085         i = base;
4086         j = lim-v2;
4087         for(;;) {
4088                 if (i < lptr) {
4089                         if ((c = (*func)(i, lptr)) == 0) {
4090                                 glob2(i, lptr -= v2);
4091                                 continue;
4092                         }
4093                         if (c < 0) {
4094                                 i += v2;
4095                                 continue;
4096                         }
4097                 }
4098
4099 begin:
4100                 if (j > hptr) {
4101                         if ((c = (*func)(hptr, j)) == 0) {
4102                                 glob2(hptr += v2, j);
4103                                 goto begin;
4104                         }
4105                         if (c > 0) {
4106                                 if (i == lptr) {
4107                                         glob3(i, hptr += v2, j);
4108                                         i = lptr += v2;
4109                                         goto begin;
4110                                 }
4111                                 glob2(i, j);
4112                                 j -= v2;
4113                                 i += v2;
4114                                 continue;
4115                         }
4116                         j -= v2;
4117                         goto begin;
4118                 }
4119
4120
4121                 if (i == lptr) {
4122                         if (lptr-base >= lim-hptr) {
4123                                 glob1(hptr+v2, lim);
4124                                 lim = lptr;
4125                         } else {
4126                                 glob1(base, lptr);
4127                                 base = hptr+v2;
4128                         }
4129                         goto top;
4130                 }
4131
4132
4133                 glob3(j, lptr -= v2, i);
4134                 j = hptr -= v2;
4135         }
4136 }
4137
4138 static void
4139 glob2(i, j)
4140 char *i, *j;
4141 {
4142         register char *index1, *index2, c;
4143         int m;
4144
4145         m = globv;
4146         index1 = i;
4147         index2 = j;
4148         do {
4149                 c = *index1;
4150                 *index1++ = *index2;
4151                 *index2++ = c;
4152         } while(--m);
4153 }
4154
4155 static void
4156 glob3(i, j, k)
4157 char *i, *j, *k;
4158 {
4159         register char *index1, *index2, *index3;
4160         int c;
4161         int m;
4162
4163         m = globv;
4164         index1 = i;
4165         index2 = j;
4166         index3 = k;
4167         do {
4168                 c = *index1;
4169                 *index1++ = *index3;
4170                 *index3++ = *index2;
4171                 *index2++ = c;
4172         } while(--m);
4173 }
4174
4175 /* -------- io.c -------- */
4176
4177 /*
4178  * shell IO
4179  */
4180
4181 static int my_getc( int ec)
4182 {
4183         register int c;
4184
4185         if(e.linep > elinep) {
4186                 while((c=readc()) != '\n' && c)
4187                         ;
4188                 err("input line too long");
4189                 gflg++;
4190                 return(c);
4191         }
4192         c = readc();
4193         if (ec != '\'' && e.iop->task != XGRAVE) {
4194                 if(c == '\\') {
4195                         c = readc();
4196                         if (c == '\n' && ec != '\"')
4197                                 return(my_getc(ec));
4198                         c |= QUOTE;
4199                 }
4200         }
4201         return(c);
4202 }
4203
4204 static void
4205 unget(c)
4206 int c;
4207 {
4208         if (e.iop >= e.iobase)
4209                 e.iop->peekc = c;
4210 }
4211
4212 static int
4213 eofc()
4214
4215 {
4216   return e.iop < e.iobase || (e.iop->peekc == 0 && e.iop->prev == 0);
4217 }
4218
4219 static int
4220 readc()
4221 {
4222         register int c;
4223
4224         for (; e.iop >= e.iobase; e.iop--)
4225                 if ((c = e.iop->peekc) != '\0') {
4226                         e.iop->peekc = 0;
4227                         return(c);
4228                 }
4229                 else {
4230                     if (e.iop->prev != 0) {
4231                         if ((c = (*e.iop->iofn)(e.iop->argp, e.iop)) != '\0') {
4232                                 if (c == -1) {
4233                                         e.iop++;
4234                                         continue;
4235                                 }
4236                                 if (e.iop == iostack)
4237                                         ioecho(c);
4238                                 return(e.iop->prev = c);
4239                         }
4240                         else if (e.iop->task == XIO && e.iop->prev != '\n') {
4241                                 e.iop->prev = 0;
4242                                 if (e.iop == iostack)
4243                                         ioecho('\n');
4244                                 return '\n';
4245                         }
4246                     }
4247                     if (e.iop->task == XIO) {
4248                         if (multiline)
4249                             return e.iop->prev = 0;
4250                         if (interactive && e.iop == iostack+1) {
4251 #ifdef BB_FEATURE_COMMAND_EDITING
4252                             current_prompt=prompt->value;
4253 #else
4254                             prs(prompt->value);
4255 #endif
4256                         }
4257                     }
4258                 }
4259         if (e.iop >= iostack)
4260                 return(0);
4261         leave();
4262         /* NOTREACHED */
4263         return(0);
4264 }
4265
4266 static void
4267 ioecho(c)
4268 char c;
4269 {
4270         if (flag['v'])
4271                 write(2, &c, sizeof c);
4272 }
4273
4274 static void
4275 pushio(argp, fn)
4276 struct ioarg *argp;
4277 int (*fn)();
4278 {
4279         if (++e.iop >= &iostack[NPUSH]) {
4280                 e.iop--;
4281                 err("Shell input nested too deeply");
4282                 gflg++;
4283                 return;
4284         }
4285         e.iop->iofn = fn;
4286
4287         if (argp->afid != AFID_NOBUF)
4288           e.iop->argp = argp;
4289         else {
4290           e.iop->argp  = ioargstack + (e.iop - iostack);
4291           *e.iop->argp = *argp;
4292           e.iop->argp->afbuf = e.iop == &iostack[0] ? &mainbuf : &sharedbuf;
4293           if (isatty(e.iop->argp->afile) == 0 &&
4294               (e.iop == &iostack[0] ||
4295                lseek(e.iop->argp->afile, 0L, 1) != -1)) {
4296             if (++bufid == AFID_NOBUF)
4297               bufid = AFID_ID;
4298             e.iop->argp->afid  = bufid;
4299           }
4300         }
4301
4302         e.iop->prev  = ~'\n';
4303         e.iop->peekc = 0;
4304         e.iop->xchar = 0;
4305         e.iop->nlcount = 0;
4306         if (fn == filechar || fn == linechar)
4307                 e.iop->task = XIO;
4308         else if (fn == gravechar || fn == qgravechar)
4309                 e.iop->task = XGRAVE;
4310         else
4311                 e.iop->task = XOTHER;
4312 }
4313
4314 static struct io *
4315 setbase(ip)
4316 struct io *ip;
4317 {
4318         register struct io *xp;
4319
4320         xp = e.iobase;
4321         e.iobase = ip;
4322         return(xp);
4323 }
4324
4325 /*
4326  * Input generating functions
4327  */
4328
4329 /*
4330  * Produce the characters of a string, then a newline, then EOF.
4331  */
4332 static int
4333 nlchar(ap)
4334 register struct ioarg *ap;
4335 {
4336         register int c;
4337
4338         if (ap->aword == NULL)
4339                 return(0);
4340         if ((c = *ap->aword++) == 0) {
4341                 ap->aword = NULL;
4342                 return('\n');
4343         }
4344         return(c);
4345 }
4346
4347 /*
4348  * Given a list of words, produce the characters
4349  * in them, with a space after each word.
4350  */
4351 static int
4352 wdchar(ap)
4353 register struct ioarg *ap;
4354 {
4355         register char c;
4356         register char **wl;
4357
4358         if ((wl = ap->awordlist) == NULL)
4359                 return(0);
4360         if (*wl != NULL) {
4361                 if ((c = *(*wl)++) != 0)
4362                         return(c & 0177);
4363                 ap->awordlist++;
4364                 return(' ');
4365         }
4366         ap->awordlist = NULL;
4367         return('\n');
4368 }
4369
4370 /*
4371  * Return the characters of a list of words,
4372  * producing a space between them.
4373  */
4374 static int
4375 dolchar(ap)
4376 register struct ioarg *ap;
4377 {
4378         register char *wp;
4379
4380         if ((wp = *ap->awordlist++) != NULL) {
4381                 PUSHIO(aword, wp, *ap->awordlist == NULL? strchar: xxchar);
4382                 return(-1);
4383         }
4384         return(0);
4385 }
4386
4387 static int
4388 xxchar(ap)
4389 register struct ioarg *ap;
4390 {
4391         register int c;
4392
4393         if (ap->aword == NULL)
4394                 return(0);
4395         if ((c = *ap->aword++) == '\0') {
4396                 ap->aword = NULL;
4397                 return(' ');
4398         }
4399         return(c);
4400 }
4401
4402 /*
4403  * Produce the characters from a single word (string).
4404  */
4405 static int
4406 strchar(ap)
4407 register struct ioarg *ap;
4408 {
4409         register int c;
4410
4411         if (ap->aword == NULL || (c = *ap->aword++) == 0)
4412                 return(0);
4413         return(c);
4414 }
4415
4416 /*
4417  * Produce quoted characters from a single word (string).
4418  */
4419 static int
4420 qstrchar(ap)
4421 register struct ioarg *ap;
4422 {
4423         register int c;
4424
4425         if (ap->aword == NULL || (c = *ap->aword++) == 0)
4426                 return(0);
4427         return(c|QUOTE);
4428 }
4429
4430 /*
4431  * Return the characters from a file.
4432  */
4433 static int
4434 filechar(ap)
4435 register struct ioarg *ap;
4436 {
4437         register int i;
4438         char c;
4439         struct iobuf *bp = ap->afbuf;
4440
4441         if (ap->afid != AFID_NOBUF) {
4442           if ((i = ap->afid != bp->id) || bp->bufp == bp->ebufp) {
4443             if (i)
4444               lseek(ap->afile, ap->afpos, 0);
4445             do {
4446               i = read(ap->afile, bp->buf, sizeof(bp->buf));
4447             } while (i < 0 && errno == EINTR);
4448             if (i <= 0) {
4449               closef(ap->afile);
4450               return 0;
4451             }
4452             bp->id = ap->afid;
4453             bp->ebufp = (bp->bufp  = bp->buf) + i;
4454           }
4455           ap->afpos++;
4456           return *bp->bufp++ & 0177;
4457         }
4458
4459 #ifdef BB_FEATURE_COMMAND_EDITING
4460         if (interactive) {
4461             static char mycommand[BUFSIZ];
4462             static int position = 0, size = 0;
4463
4464             while (size == 0 || position >= size) {
4465                 cmdedit_read_input(current_prompt, mycommand);
4466                 cmdedit_terminate();
4467                 size = strlen(mycommand);
4468                 position = 0;
4469             }
4470             c = mycommand[position];
4471             position++;
4472             return(c);
4473         } else
4474 #endif
4475         {
4476                 do {
4477                         i = read(ap->afile, &c, sizeof(c));
4478                 } while (i < 0 && errno == EINTR);
4479                 return(i == sizeof(c)? c&0177: (closef(ap->afile), 0));
4480         }
4481 }
4482
4483 /*
4484  * Return the characters from a here temp file.
4485  */
4486 static int
4487 herechar(ap)
4488 register struct ioarg *ap;
4489 {
4490         char c;
4491
4492
4493         if (read(ap->afile, &c, sizeof(c)) != sizeof(c)) {
4494                 close(ap->afile);
4495                 c = 0;
4496         }
4497         return (c);
4498
4499 }
4500
4501 /*
4502  * Return the characters produced by a process (`...`).
4503  * Quote them if required, and remove any trailing newline characters.
4504  */
4505 static int
4506 gravechar(ap, iop)
4507 struct ioarg *ap;
4508 struct io *iop;
4509 {
4510         register int c;
4511
4512         if ((c = qgravechar(ap, iop)&~QUOTE) == '\n')
4513                 c = ' ';
4514         return(c);
4515 }
4516
4517 static int
4518 qgravechar(ap, iop)
4519 register struct ioarg *ap;
4520 struct io *iop;
4521 {
4522         register int c;
4523
4524         if (iop->xchar) {
4525                 if (iop->nlcount) {
4526                         iop->nlcount--;
4527                         return('\n'|QUOTE);
4528                 }
4529                 c = iop->xchar;
4530                 iop->xchar = 0;
4531         } else if ((c = filechar(ap)) == '\n') {
4532                 iop->nlcount = 1;
4533                 while ((c = filechar(ap)) == '\n')
4534                         iop->nlcount++;
4535                 iop->xchar = c;
4536                 if (c == 0)
4537                         return(c);
4538                 iop->nlcount--;
4539                 c = '\n';
4540         }
4541         return(c!=0? c|QUOTE: 0);
4542 }
4543
4544 /*
4545  * Return a single command (usually the first line) from a file.
4546  */
4547 static int
4548 linechar(ap)
4549 register struct ioarg *ap;
4550 {
4551         register int c;
4552
4553         if ((c = filechar(ap)) == '\n') {
4554                 if (!multiline) {
4555                         closef(ap->afile);
4556                         ap->afile = -1; /* illegal value */
4557                 }
4558         }
4559         return(c);
4560 }
4561
4562 static void
4563 prs(s)
4564 register char *s;
4565 {
4566         if (*s)
4567                 write(2, s, strlen(s));
4568 }
4569
4570 static void
4571 prn(u)
4572 unsigned u;
4573 {
4574         prs(itoa(u, 0));
4575 }
4576
4577 static void
4578 closef(i)
4579 register int i;
4580 {
4581         if (i > 2)
4582                 close(i);
4583 }
4584
4585 static void
4586 closeall()
4587 {
4588         register int u;
4589
4590         for (u=NUFILE; u<NOFILE;)
4591                 close(u++);
4592 }
4593
4594 /*
4595  * remap fd into Shell's fd space
4596  */
4597 static int
4598 remap(fd)
4599 register int fd;
4600 {
4601         register int i;
4602         int map[NOFILE];
4603
4604         if (fd < e.iofd) {
4605                 for (i=0; i<NOFILE; i++)
4606                         map[i] = 0;
4607                 do {
4608                         map[fd] = 1;
4609                         fd = dup(fd);
4610                 } while (fd >= 0 && fd < e.iofd);
4611                 for (i=0; i<NOFILE; i++)
4612                         if (map[i])
4613                                 close(i);
4614                 if (fd < 0)
4615                         err("too many files open in shell");
4616         }
4617         return(fd);
4618 }
4619
4620 static int
4621 openpipe(pv)
4622 register int *pv;
4623 {
4624         register int i;
4625
4626         if ((i = pipe(pv)) < 0)
4627                 err("can't create pipe - try again");
4628         return(i);
4629 }
4630
4631 static void
4632 closepipe(pv)
4633 register int *pv;
4634 {
4635         if (pv != NULL) {
4636                 close(*pv++);
4637                 close(*pv);
4638         }
4639 }
4640
4641 /* -------- here.c -------- */
4642
4643 /*
4644  * here documents
4645  */
4646
4647 static void
4648 markhere(s, iop)
4649 register char *s;
4650 struct ioword *iop;
4651 {
4652         register struct here *h, *lh;
4653
4654         h = (struct here *) space(sizeof(struct here));
4655         if (h == 0)
4656                 return;
4657         h->h_tag = evalstr(s, DOSUB);
4658         if (h->h_tag == 0)
4659                 return;
4660         h->h_iop = iop;
4661         iop->io_name = 0;
4662         h->h_next = NULL;
4663         if (inhere == 0)
4664                 inhere = h;
4665         else
4666                 for (lh = inhere; lh!=NULL; lh = lh->h_next)
4667                         if (lh->h_next == 0) {
4668                                 lh->h_next = h;
4669                                 break;
4670                         }
4671         iop->io_flag |= IOHERE|IOXHERE;
4672         for (s = h->h_tag; *s; s++)
4673                 if (*s & QUOTE) {
4674                         iop->io_flag &= ~ IOXHERE;
4675                         *s &= ~ QUOTE;
4676                 }
4677         h->h_dosub = iop->io_flag & IOXHERE;
4678 }
4679
4680 static void
4681 gethere()
4682 {
4683         register struct here *h, *hp;
4684
4685         /* Scan here files first leaving inhere list in place */
4686         for (hp = h = inhere; h != NULL; hp = h, h = h->h_next)
4687           readhere(&h->h_iop->io_name, h->h_tag, h->h_dosub? 0: '\'');
4688
4689         /* Make inhere list active - keep list intact for scraphere */
4690         if (hp != NULL) {
4691           hp->h_next = acthere;
4692           acthere    = inhere;
4693           inhere     = NULL;
4694         }
4695 }
4696
4697 static void
4698 readhere(name, s, ec)
4699 char **name;
4700 register char *s;
4701 int ec;
4702 {
4703         int tf;
4704         char tname[30] = ".msh_XXXXXX";
4705         register int c;
4706         jmp_buf ev;
4707         char myline [LINELIM+1];
4708         char *thenext;
4709
4710         tf = mkstemp(tname);
4711         if (tf < 0)
4712                 return;
4713         *name = strsave(tname, areanum);
4714         if (newenv(setjmp(errpt = ev)) != 0)
4715                 unlink(tname);
4716         else {
4717                 pushio(e.iop->argp, e.iop->iofn);
4718                 e.iobase = e.iop;
4719                 for (;;) {
4720                     if (interactive && e.iop <= iostack) {
4721 #ifdef BB_FEATURE_COMMAND_EDITING
4722                             current_prompt=cprompt->value;
4723 #else
4724                             prs(cprompt->value);
4725 #endif
4726                         }
4727                         thenext = myline;
4728                         while ((c = my_getc(ec)) != '\n' && c) {
4729                                 if (ec == '\'')
4730                                         c &= ~ QUOTE;
4731                                 if (thenext >= &myline[LINELIM]) {
4732                                         c = 0;
4733                                         break;
4734                                 }
4735                                 *thenext++ = c;
4736                         }
4737                         *thenext = 0;
4738                         if (strcmp(s, myline) == 0 || c == 0)
4739                                 break;
4740                         *thenext++ = '\n';
4741                         write (tf, myline, (int)(thenext-myline));
4742                 }
4743                 if (c == 0) {
4744                         prs("here document `"); prs(s); err("' unclosed");
4745                 }
4746                 quitenv();
4747         }
4748         close(tf);
4749 }
4750
4751 /*
4752  * open here temp file.
4753  * if unquoted here, expand here temp file into second temp file.
4754  */
4755 static int
4756 herein(hname, xdoll)
4757 char *hname;
4758 int xdoll;
4759 {
4760         register int hf;
4761         int tf;
4762
4763 #if __GNUC__
4764         /* Avoid longjmp clobbering */
4765         (void) &tf;
4766 #endif
4767         if (hname == 0)
4768                 return(-1);
4769         hf = open(hname, 0);
4770         if (hf < 0)
4771                 return (-1);
4772         if (xdoll) {
4773                 char c;
4774                 char tname[30] = ".msh_XXXXXX";
4775                 jmp_buf ev;
4776
4777                 tf = mkstemp(tname);
4778                 if (tf < 0)
4779                         return (-1);
4780                 if (newenv(setjmp(errpt = ev)) == 0) {
4781                         PUSHIO(afile, hf, herechar);
4782                         setbase(e.iop);
4783                         while ((c = subgetc(0, 0)) != 0) {
4784                                 c &= ~ QUOTE;
4785                                 write(tf, &c, sizeof c);
4786                         }
4787                         quitenv();
4788                 } else
4789                         unlink(tname);
4790                 close(tf);
4791                 tf = open(tname, 0);
4792                 unlink(tname);
4793                 return (tf);
4794         } else
4795                 return (hf);
4796 }
4797
4798 static void
4799 scraphere()
4800 {
4801         register struct here *h;
4802
4803         for (h = inhere; h != NULL; h = h->h_next) {
4804                 if (h->h_iop && h->h_iop->io_name)
4805                   unlink(h->h_iop->io_name);
4806         }
4807         inhere = NULL;
4808 }
4809
4810 /* unlink here temp files before a freearea(area) */
4811 static void
4812 freehere(area)
4813 int area;
4814 {
4815         register struct here *h, *hl;
4816
4817         hl = NULL;
4818         for (h = acthere; h != NULL; h = h->h_next)
4819                 if (getarea((char *) h) >= area) {
4820                         if (h->h_iop->io_name != NULL)
4821                                 unlink(h->h_iop->io_name);
4822                         if (hl == NULL)
4823                                 acthere = h->h_next;
4824                         else
4825                                 hl->h_next = h->h_next;
4826                 } else
4827                         hl = h;
4828 }
4829
4830
4831
4832 /*
4833  * Copyright (c) 1987,1997, Prentice Hall
4834  * All rights reserved.
4835  *
4836  * Redistribution and use of the MINIX operating system in source and
4837  * binary forms, with or without modification, are permitted provided
4838  * that the following conditions are met:
4839  *
4840  * Redistributions of source code must retain the above copyright
4841  * notice, this list of conditions and the following disclaimer.
4842  *
4843  * Redistributions in binary form must reproduce the above
4844  * copyright notice, this list of conditions and the following
4845  * disclaimer in the documentation and/or other materials provided
4846  * with the distribution.
4847  *
4848  * Neither the name of Prentice Hall nor the names of the software
4849  * authors or contributors may be used to endorse or promote
4850  * products derived from this software without specific prior
4851  * written permission.
4852  *
4853  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS, AUTHORS, AND
4854  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
4855  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
4856  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
4857  * IN NO EVENT SHALL PRENTICE HALL OR ANY AUTHORS OR CONTRIBUTORS BE
4858  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
4859  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
4860  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
4861  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
4862  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
4863  * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
4864  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
4865  *
4866  */
4867