ash: implement ">&file" bashism. ~100 bytes.

diff --git a/shell/ash.c b/shell/ash.c
index 0878237bf980485895eaf732c950fbfc59ea1369..9ccb1c9ee1473b173ae59e645654d46e5484bcd7 100644 (file)
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -8,7 +8,6 @@
  * Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
  * was re-ported from NetBSD and debianized.
  *
- *
  * This code is derived from software contributed to Berkeley by
  * Kenneth Almquist.
  *
@@ -28,7 +27,6 @@
  * used in busybox and size optimizations,
  * rewrote arith (see notes to this), added locale support,
  * rewrote dynamic variables.
- *
  */
 
 /*
@@ -247,8 +245,17 @@ extern struct globals_misc *const ash_ptr_to_globals_misc;
 } while (0)
 
 
-/* ============ Interrupts / exceptions */
+/* ============ Utility functions */
+static int isdigit_str9(const char *str)
+{
+       int maxlen = 9 + 1; /* max 9 digits: 999999999 */
+       while (--maxlen && isdigit(*str))
+               str++;
+       return (*str == '\0');
+}
+
 
+/* ============ Interrupts / exceptions */
 /*
  * These macros allow the user to suspend the handling of interrupt signals
  * over a period of time.  This is similar to SIGHOLD or to sigblock, but
@@ -500,32 +507,35 @@ static const char dolatstr[] ALIGN1 = {
        CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0'
 };
 
-#define NCMD 0
-#define NPIPE 1
-#define NREDIR 2
-#define NBACKGND 3
+#define NCMD      0
+#define NPIPE     1
+#define NREDIR    2
+#define NBACKGND  3
 #define NSUBSHELL 4
-#define NAND 5
-#define NOR 6
-#define NSEMI 7
-#define NIF 8
-#define NWHILE 9
-#define NUNTIL 10
-#define NFOR 11
-#define NCASE 12
-#define NCLIST 13
-#define NDEFUN 14
-#define NARG 15
-#define NTO 16
-#define NCLOBBER 17
-#define NFROM 18
-#define NFROMTO 19
-#define NAPPEND 20
-#define NTOFD 21
-#define NFROMFD 22
-#define NHERE 23
-#define NXHERE 24
-#define NNOT 25
+#define NAND      5
+#define NOR       6
+#define NSEMI     7
+#define NIF       8
+#define NWHILE    9
+#define NUNTIL   10
+#define NFOR     11
+#define NCASE    12
+#define NCLIST   13
+#define NDEFUN   14
+#define NARG     15
+#define NTO      16
+#if ENABLE_ASH_BASH_COMPAT
+#define NTO2     17
+#endif
+#define NCLOBBER 18
+#define NFROM    19
+#define NFROMTO  20
+#define NAPPEND  21
+#define NTOFD    22
+#define NFROMFD  23
+#define NHERE    24
+#define NXHERE   25
+#define NNOT     26
 
 union node;
 
@@ -588,20 +598,26 @@ struct narg {
        struct nodelist *backquote;
 };
 
+/* nfile and ndup layout must match!
+ * NTOFD (>&fdnum) uses ndup structure, but we may discover mid-flight
+ * that it is actually NTO2 (>&file), and change its type.
+ */
 struct nfile {
        smallint type;
        union node *next;
        int fd;
+       int _unused_dupfd;
        union node *fname;
        char *expfname;
 };
 
 struct ndup {
        smallint type;
-       union node *next; /* must match nfile's layout */
-       int fd; /* must match nfile's layout */
+       union node *next;
+       int fd;
        int dupfd;
        union node *vname;
+       char *_unused_expfname;
 };
 
 struct nhere {
@@ -904,8 +920,11 @@ shcmd(union node *cmd, FILE *fp)
                case NTO:      s = ">>"+1; dftfd = 1; break;
                case NCLOBBER: s = ">|"; dftfd = 1; break;
                case NAPPEND:  s = ">>"; dftfd = 1; break;
+#if ENABLE_ASH_BASH_COMPAT
+               case NTO2:
+#endif
                case NTOFD:    s = ">&"; dftfd = 1; break;
-               case NFROM:    s = "<";  break;
+               case NFROM:    s = "<"; break;
                case NFROMFD:  s = "<&"; break;
                case NFROMTO:  s = "<>"; break;
                default:       s = "*error*"; break;
@@ -4408,6 +4427,9 @@ cmdtxt(union node *n)
        case NAPPEND:
                p = ">>";
                goto redir;
+#if ENABLE_ASH_BASH_COMPAT
+       case NTO2:
+#endif
        case NTOFD:
                p = ">&";
                goto redir;
@@ -4797,6 +4819,9 @@ openredirect(union node *redir)
                        goto ecreate;
                break;
        case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+       case NTO2:
+#endif
                /* Take care of noclobber mode. */
                if (Cflag) {
                        fname = redir->nfile.expfname;
@@ -4959,6 +4984,10 @@ redirect(union node *redir, int flags)
                union node *tmp = redir;
                do {
                        sv_pos++;
+#if ENABLE_ASH_BASH_COMPAT
+                       if (redir->nfile.type == NTO2)
+                               sv_pos++;
+#endif
                        tmp = tmp->nfile.next;
                } while (tmp);
                sv = ckmalloc(sizeof(*sv) + sv_pos * sizeof(sv->two_fd[0]));
@@ -4997,6 +5026,9 @@ redirect(union node *redir, int flags)
                                continue;
                        }
                }
+#if ENABLE_ASH_BASH_COMPAT
+ redirect_more:
+#endif
                if (need_to_remember(sv, fd)) {
                        /* Copy old descriptor */
                        i = fcntl(fd, F_DUPFD, 10);
@@ -5039,8 +5071,19 @@ redirect(union node *redir, int flags)
                        }
                } else if (fd != newfd) { /* move newfd to fd */
                        copyfd(newfd, fd | COPYFD_EXACT);
-                       close(newfd);
+#if ENABLE_ASH_BASH_COMPAT
+                       if (!(redir->nfile.type == NTO2 && fd == 2))
+#endif
+                               close(newfd);
+               }
+#if ENABLE_ASH_BASH_COMPAT
+               if (redir->nfile.type == NTO2 && fd == 1) {
+                       /* We already redirected it to fd 1, now copy it to 2 */
+                       newfd = 1;
+                       fd = 2;
+                       goto redirect_more;
                }
+#endif
        } while ((redir = redir->nfile.next) != NULL);
 
        INT_ON;
@@ -7641,6 +7684,9 @@ calcsize(union node *n)
                calcsize(n->narg.next);
                break;
        case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+       case NTO2:
+#endif
        case NCLOBBER:
        case NFROM:
        case NFROMTO:
@@ -7754,6 +7800,9 @@ copynode(union node *n)
                new->narg.next = copynode(n->narg.next);
                break;
        case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+       case NTO2:
+#endif
        case NCLOBBER:
        case NFROM:
        case NFROMTO:
@@ -8175,17 +8224,33 @@ expredir(union node *n)
                case NFROMTO:
                case NFROM:
                case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+               case NTO2:
+#endif
                case NCLOBBER:
                case NAPPEND:
                        expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR);
+#if ENABLE_ASH_BASH_COMPAT
+ store_expfname:
+#endif
                        redir->nfile.expfname = fn.list->text;
                        break;
                case NFROMFD:
-               case NTOFD:
+               case NTOFD: /* >& */
                        if (redir->ndup.vname) {
                                expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE);
                                if (fn.list == NULL)
                                        ash_msg_and_raise_error("redir error");
+#if ENABLE_ASH_BASH_COMPAT
+//FIXME: we used expandarg with different args!
+                               if (!isdigit_str9(fn.list->text)) {
+                                       /* >&file, not >&fd */
+                                       if (redir->nfile.fd != 1) /* 123>&file - BAD */
+                                               ash_msg_and_raise_error("redir error");
+                                       redir->type = NTO2;
+                                       goto store_expfname;
+                               }
+#endif
                                fixredir(redir, fn.list->text, 1);
                        }
                        break;
@@ -10126,7 +10191,7 @@ fixredir(union node *n, const char *text, int err)
                n->ndup.dupfd = -1;
        else {
                if (err)
-                       raise_error_syntax("Bad fd number");
+                       raise_error_syntax("bad fd number");
                n->ndup.vname = makename();
        }
 }
@@ -10169,7 +10234,7 @@ parsefname(void)
                        n->type = NXHERE;
                TRACE(("Here document %d\n", n->type));
                if (!noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN)
-                       raise_error_syntax("Illegal eof marker for << redirection");
+                       raise_error_syntax("illegal eof marker for << redirection");
                rmescapes(wordtext);
                here->eofmark = wordtext;
                here->next = NULL;
@@ -10261,7 +10326,7 @@ simplecmd(void)
                                if (!goodname(name)
                                 || ((bcmd = find_builtin(name)) && IS_BUILTIN_SPECIAL(bcmd))
                                ) {
-                                       raise_error_syntax("Bad function name");
+                                       raise_error_syntax("bad function name");
                                }
                                n->type = NDEFUN;
                                checkkwd = CHKNL | CHKKWD | CHKALIAS;
@@ -10346,7 +10411,7 @@ parse_command(void)
        }
        case TFOR:
                if (readtoken() != TWORD || quoteflag || !goodname(wordtext))
-                       raise_error_syntax("Bad for loop variable");
+                       raise_error_syntax("bad for loop variable");
                n1 = stzalloc(sizeof(struct nfor));
                n1->type = NFOR;
                n1->nfor.var = wordtext;
@@ -10748,25 +10813,21 @@ readtoken1(int firstc, int syntax, char *eofmark, int striptabs)
  endword:
 #if ENABLE_ASH_MATH_SUPPORT
        if (syntax == ARISYNTAX)
-               raise_error_syntax("Missing '))'");
+               raise_error_syntax("missing '))'");
 #endif
        if (syntax != BASESYNTAX && !parsebackquote && eofmark == NULL)
-               raise_error_syntax("Unterminated quoted string");
+               raise_error_syntax("unterminated quoted string");
        if (varnest != 0) {
                startlinno = plinno;
                /* { */
-               raise_error_syntax("Missing '}'");
+               raise_error_syntax("missing '}'");
        }
        USTPUTC('\0', out);
        len = out - (char *)stackblock();
        out = stackblock();
        if (eofmark == NULL) {
                if ((c == '>' || c == '<') && quotef == 0) {
-                       int maxlen = 9 + 1; /* max 9 digit fd#: 999999999 */
-                       char *np = out;
-                       while (--maxlen && isdigit(*np))
-                               np++;
-                       if (*np == '\0') {
+                       if (isdigit_str9(out)) {
                                PARSEREDIR(); /* passed as params: out, c */
                                lasttoken = TREDIR;
                                return lasttoken;
@@ -10841,6 +10902,7 @@ parseredir: {
                        np->type = NCLOBBER;
                else if (c == '&')
                        np->type = NTOFD;
+                       /* it also can be NTO2 (>&file), but we can't figure it out yet */
                else {
                        np->type = NTO;
                        pungetc();
@@ -10954,8 +11016,10 @@ parsesub: {
                } else if (is_special(c)) {
                        USTPUTC(c, out);
                        c = pgetc();
-               } else
- badsub:               raise_error_syntax("Bad substitution");
+               } else {
+ badsub:
+                       raise_error_syntax("bad substitution");
+               }
 
                STPUTC('=', out);
                flags = 0;