Patch from Jonas Holmberg, adjusted by Robert Schwebel, and
authorEric Andersen <andersen@codepoet.org>
Fri, 14 Mar 2003 16:05:59 +0000 (16:05 -0000)
committerEric Andersen <andersen@codepoet.org>
Fri, 14 Mar 2003 16:05:59 +0000 (16:05 -0000)
later re-adjusted by me to fix msh backtick handling

shell/msh.c

index 60fc1dc347e29168719552ed3dda73fb7b899bf9..53f643de12ae96e709ef5aa86c5fce77b42455b6 100644 (file)
@@ -5,6 +5,11 @@
  * This version of the Minix shell was adapted for use in busybox
  * by Erik Andersen <andersee@debian.org>
  *
+ * - backtick expansion did not work properly
+ *   Jonas Holmberg <jonas.holmberg@axis.com>
+ *   Robert Schwebel <r.schwebel@pengutronix.de>
+ *   Erik Andersen <andersee@debian.org>
+ *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
@@ -222,7 +227,7 @@ static char *space (int n );
 static char *strsave (char *s, int a );
 static char *evalstr (char *cp, int f );
 static char *putn (int n );
-static char *itoa (unsigned u, int n );
+static char *itoa (int n );
 static char *unquote (char *as );
 static struct var *lookup (char *n );
 static int rlookup (char *n );
@@ -664,7 +669,6 @@ static int  heedint =1;
 static struct env e ={line, iostack, iostack-1, (xint *)NULL, FDBASE, (struct env *)NULL};
 static void (*qflag)(int) = SIG_IGN;
 static char    shellname[] = "/bin/sh";
-static char    search[] = ":/bin:/usr/bin";
 static int     startl;
 static int     peeksym;
 static int     nlseen;
@@ -687,7 +691,6 @@ static void * brkaddr;
 static char * current_prompt;
 #endif
 
-
 /* -------- sh.c -------- */
 /*
  * shell
@@ -722,11 +725,15 @@ extern int msh_main(int argc, char **argv)
                setval(homedir, "/");
        export(homedir);
 
-       setval(lookup("$"), itoa(getpid(), 5));
+       setval(lookup("$"), putn(getpid()));
 
        path = lookup("PATH");
-       if (path->value == null)
-               setval(path, search);
+       if (path->value == null) {
+               if (geteuid() == 0)
+                       setval(path, "/sbin:/bin:/usr/sbin:/usr/bin");
+               else
+                       setval(path, "/bin:/usr/bin");
+       }
        export(path);
 
        ifs = lookup("IFS");
@@ -858,7 +865,7 @@ setdash()
 
        cp = m;
        for (c='a'; c<='z'; c++)
-               if (flag[c])
+               if (flag[(int)c])
                        *cp++ = c;
        *cp = 0;
        setval(lookup("-"), m);
@@ -1047,32 +1054,16 @@ static char *
 putn(n)
 register int n;
 {
-       return(itoa(n, -1));
+       return(itoa(n));
 }
 
 static char *
-itoa(u, n)
-register unsigned u;
-int n;
+itoa(n)
+register int n;
 {
-       register char *cp;
        static char s[20];
-       int m;
-
-       m = 0;
-       if (n < 0 && (int) u < 0) {
-               m++;
-               u = -u;
-       }
-       cp = s+sizeof(s);
-       *--cp = 0;
-       do {
-               *--cp = u%10 + '0';
-               u /= 10;
-       } while (--n > 0 || u);
-       if (m)
-               *--cp = '-';
-       return(cp);
+       snprintf(s, sizeof(s), "%u", n);
+       return(s);
 }
 
 static void
@@ -2326,6 +2317,9 @@ int act;
 
        switch(t->type) {
        case TPAREN:
+               rv = execute(t->left, pin, pout, 0);
+               break;
+                       
        case TCOM:
                {
                        int child;
@@ -2877,12 +2871,12 @@ char *c, **v, **envp;
                        *v = e.linep;
                        tp = *--v;
                        *v = e.linep;
-                       execve("/bin/sh", v, envp);
+                       execve(shellname, v, envp);
                        *v = tp;
                        return("no Shell");
 
                case ENOMEM:
-                       return("program too big");
+                       return((char*)memory_exhausted);
 
                case E2BIG:
                        return("argument list too long");
@@ -3643,7 +3637,7 @@ loop:
  */
 static int
 subgetc(ec, quoted)
-register int ec;
+register char ec;
 int quoted;
 {
        register char c;
@@ -3770,59 +3764,154 @@ int quoted;
 /*
  * Run the command in `...` and read its output.
  */
+
 static int
 grave(quoted)
 int quoted;
 {
-       register int i;
        char *cp;
+       register int i;
+       int j;
        int pf[2];
+       static char child_cmd[LINELIM];
+       char *src;
+       char *dest;
+       int count;
+       int ignore;
+       int ignore_once;
+       char *argument_list[4];
 
 #if __GNUC__
        /* Avoid longjmp clobbering */
        (void) &cp;
 #endif
+       
        for (cp = e.iop->argp->aword; *cp != '`'; cp++)
                if (*cp == 0) {
                        err("no closing `");
                        return(0);
                }
+
+       /* string copy with dollar expansion */
+       src = e.iop->argp->aword;
+       dest = child_cmd;
+       count = 0;
+       ignore = 0;
+       ignore_once = 0;
+       while ((*src != '`') && (count < LINELIM)) {
+               if (*src == '\'')
+                       ignore = !ignore;
+               if (*src == '\\')
+                       ignore_once = 1;
+               if (*src == '$' && !ignore && !ignore_once) {
+                       struct var *vp;
+                       char var_name[LINELIM];
+                       char alt_value[LINELIM];
+                       int var_index = 0;
+                       int alt_index = 0;
+                       char operator = 0;
+                       int braces = 0;
+                       char *value;
+
+                       src++;
+                       if (*src == '{') {
+                               braces = 1;
+                               src++;
+                       }
+
+                       var_name[var_index++] = *src++;
+                       while (isalnum(*src))
+                               var_name[var_index++] = *src++;
+                       var_name[var_index] = 0;
+
+                       if (braces) {
+                               switch (*src) {
+                               case '}':
+                                       break;
+                               case '-':
+                               case '=':
+                               case '+':
+                               case '?':
+                                       operator = *src;
+                                       break;
+                               default:
+                                       err("unclosed ${\n");
+                                       return(0);
+                               }
+                               if (operator) { 
+                                       src++;
+                                       while (*src && (*src != '}')) {
+                                               alt_value[alt_index++] = *src++;
+                                       }
+                                       alt_value[alt_index] = 0;
+                                       if (*src != '}') {
+                                               err("unclosed ${\n");
+                                               return(0);
+                                       }
+                               }
+                               src++;
+                       }
+
+                       vp = lookup(var_name);
+                       if (vp->value != null)
+                               value = (operator == '+')? alt_value : vp->value;
+                       else if (operator == '?') {
+                               err(alt_value);
+                               return(0);
+                       } else if (alt_index && (operator != '+')) {
+                               value = alt_value;
+                               if (operator == '=')
+                                       setval(vp, value);
+                       } else
+                               continue;
+
+                       while (*value && (count < LINELIM)) {
+                               *dest++ = *value++;
+                               count++;
+                       }
+               } else {
+                       *dest++ = *src++;
+                       count++;
+                       ignore_once = 0;
+               }
+       }
+       *dest = '\0';
+       
        if (openpipe(pf) < 0)
                return(0);
-       if ((i = vfork()) == -1) {
+       while ((i = vfork()) == -1 && errno == EAGAIN)
+               ;
+       if (i < 0) {
                closepipe(pf);
-               err("try again");
+               err((char*)memory_exhausted);
                return(0);
        }
        if (i != 0) {
+               waitpid(i, NULL, 0);
                e.iop->argp->aword = ++cp;
                close(pf[1]);
                PUSHIO(afile, remap(pf[0]), (int(*)(struct ioarg *))((quoted)? qgravechar: gravechar));
                return(1);
        }
-       *cp = 0;
        /* allow trapped signals */
-       for (i=0; i<=_NSIG; i++)
-               if (ourtrap[i] && signal(i, SIG_IGN) != SIG_IGN)
-                       signal(i, SIG_DFL);
+       /* XXX - Maybe this signal stuff should go as well? */
+       for (j=0; j<=_NSIG; j++)
+               if (ourtrap[j] && signal(j, SIG_IGN) != SIG_IGN)
+                       signal(j, SIG_DFL);
+       
        dup2(pf[1], 1);
        closepipe(pf);
-       flag['e'] = 0;
-       flag['v'] = 0;
-       flag['n'] = 0;
-       cp = strsave(e.iop->argp->aword, 0);
-       areanum = 1;
-       freehere(areanum);
-       freearea(areanum);      /* free old space */
-       e.oenv = NULL;
-       e.iop = (e.iobase = iostack) - 1;
-       unquote(cp);
-       interactive = 0;
-       PUSHIO(aword, cp, nlchar);
-       onecommand();
-       exit(1);
+
+       argument_list[0] = shellname;
+       argument_list[1] = "-c";
+       argument_list[2] = child_cmd;
+       argument_list[3] = 0;
+
+       prs(rexecve(argument_list[0], argument_list, makenv()));
+       _exit(1);
 }
 
+
 static char *
 unquote(as)
 register char *as;
@@ -4194,7 +4283,7 @@ static int my_getc( int ec)
                return(c);
        }
        c = readc();
-       if (ec != '\'' && e.iop->task != XGRAVE) {
+       if ((ec != '\'') && (ec != '`') && (e.iop->task != XGRAVE)) {
                if(c == '\\') {
                        c = readc();
                        if (c == '\n' && ec != '\"')
@@ -4457,7 +4546,7 @@ register struct ioarg *ap;
        }
 
 #ifdef CONFIG_FEATURE_COMMAND_EDITING
-       if (interactive) {
+       if (interactive && isatty(ap->afile)) {
            static char mycommand[BUFSIZ];
            static int position = 0, size = 0;
 
@@ -4568,7 +4657,7 @@ static void
 prn(u)
 unsigned u;
 {
-       prs(itoa(u, 0));
+       prs(itoa(u));
 }
 
 static void