[BusyBox] [PATCH] msh backtick problems solved
Robert Schwebel
robert at schwebel.de
Tue Mar 11 14:49:04 UTC 2003
Hi,
Thanks to Jonas Holmberg's working port of the original minix shell I
was able to fix busybox-msh's backtick expansion problems. A patch is
attached.
I assume somebody with more shell experience than myself should have a
look at the patch before adding it, as I'm not really sure what I did...
The only problem which I found to be left is that the basename magic
doesn't work properly; if you start 'busybox msh' I still get this 'not
found' error. If you add a link for msh it works. But that's definitely
something I'll not have a look at anymore tonight....
Robert
--
Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
Pengutronix - Linux Solutions for Science and Industry
Braunschweiger Str. 79, 31134 Hildesheim, Germany
Handelsregister: Amtsgericht Hildesheim, HRA 2686
Phone: +49-5121-28619-0 | Fax: +49-5121-28619-4
-------------- next part --------------
--- msh-orig.c Tue Mar 11 12:29:45 2003
+++ msh.c Tue Mar 11 22:45:59 2003
@@ -5,6 +5,10 @@
* This version of the Minix shell was adapted for use in busybox
* by Erik Andersen <andersee at debian.org>
*
+ * - backtick expansion did not work properly
+ * Jonas Holmberg <jonas.holmberg at axis.com>
+ * Robert Schwebel <r.schwebel at pengutronix.de>
+ *
* 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
@@ -250,10 +254,10 @@
/*
* error handling
*/
-static void leave (void); /* abort shell (or fail in subshell) */
-static void fail (void); /* fail but return to process next command */
+static void leave (void); /* abort shell (or fail in subshell) */
+static void fail (void); /* fail but return to process next command */
static void warn (char *s );
-static void sig (int i ); /* default signal handler */
+static void sig (int i ); /* default signal handler */
@@ -536,6 +540,7 @@
static void glob1 (char *base, char *lim );
static void glob2 (char *i, char *j );
static void glob3 (char *i, char *j, char *k );
+static char * memcopy (char *ato, char *from, int nb );
static void readhere (char **name, char *s, int ec );
static void pushio (struct ioarg *argp, int (*f)(struct ioarg *));
static int xxchar(struct ioarg *ap );
@@ -687,6 +692,7 @@
static char * current_prompt;
#endif
+static char *subshellname;
/* -------- sh.c -------- */
/*
@@ -712,6 +718,36 @@
closeall();
areanum = 1;
+ /* FIXME: make this compatible to busybox's naming scheme */
+ /* 'busybox msh' does not work, you have to create a link */
+ if ((argv[0][0] == '-') && (argv[0][1] != '\0')) {
+ if (!(subshellname = space(strlen(argv[0]))))
+ err("out of memory\n");
+ else {
+ memcopy(subshellname, argv[0] + 1, strlen(argv[0]));
+ }
+ } else {
+ if ((argv[0][0] != '/') && strchr(argv[0], '/')) {
+ char *cwd = getcwd(NULL, 0);
+ if (!(subshellname = space(strlen(cwd) + 1 +
+ strlen(argv[0]) + 1)))
+ err("out of memory\n");
+ else {
+ memcopy(subshellname, cwd, strlen(cwd));
+ subshellname[strlen(cwd)] = '/';
+ memcopy(subshellname + strlen(cwd) + 1,
+ argv[0], strlen(argv[0]) + 1);
+ free(cwd);
+ }
+
+ } else {
+ if (!(subshellname = space(strlen(argv[0]) + 1)))
+ err("out of memory\n");
+ else
+ memcopy(subshellname, argv[0], strlen(argv[0]) + 1);
+ }
+ }
+
shell = lookup("SHELL");
if (shell->value == null)
setval(shell, shellname);
@@ -722,11 +758,15 @@
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 +898,7 @@
cp = m;
for (c='a'; c<='z'; c++)
- if (flag[c])
+ if (flag[(int)c])
*cp++ = c;
*cp = 0;
setval(lookup("-"), m);
@@ -2326,6 +2366,9 @@
switch(t->type) {
case TPAREN:
+ rv = execute(t->left, pin, pout, 0);
+ break;
+
case TCOM:
{
int child;
@@ -3643,7 +3686,7 @@
*/
static int
subgetc(ec, quoted)
-register int ec;
+register char ec;
int quoted;
{
register char c;
@@ -3675,7 +3718,7 @@
int otask;
struct io *oiop;
char *dolp;
- register char *s, c, *cp=NULL;
+ register char *s, c, *cp = NULL;
struct var *vp;
c = readc();
@@ -3770,59 +3813,154 @@
/*
* 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()) == EAGAIN)
+ ;
+ if (i < 0) {
closepipe(pf);
- err("try again");
+ err("Out of memory");
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] = subshellname;
+ 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;
@@ -4176,6 +4314,20 @@
} while(--m);
}
+char *
+memcopy(ato, from, nb)
+register char *ato, *from;
+register int nb;
+{
+ register char *to;
+
+ to = ato;
+ while (--nb >= 0)
+ *to++ = *from++;
+ return(ato);
+}
+
+
/* -------- io.c -------- */
/*
@@ -4194,7 +4346,7 @@
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 != '\"')
@@ -4444,7 +4596,9 @@
if ((i = ap->afid != bp->id) || bp->bufp == bp->ebufp) {
if (i)
lseek(ap->afile, ap->afpos, 0);
- i = safe_read(ap->afile, bp->buf, sizeof(bp->buf));
+ do {
+ i = read(ap->afile, bp->buf, sizeof(bp->buf));
+ } while (i < 0 && errno == EINTR);
if (i <= 0) {
closef(ap->afile);
return 0;
@@ -4457,22 +4611,24 @@
}
#ifdef CONFIG_FEATURE_COMMAND_EDITING
- if (interactive) {
+ if (interactive && isatty(ap->afile)) {
static char mycommand[BUFSIZ];
static int position = 0, size = 0;
while (size == 0 || position >= size) {
- cmdedit_read_input(current_prompt, mycommand);
- size = strlen(mycommand);
- position = 0;
+ cmdedit_read_input(current_prompt, mycommand);
+ size = strlen(mycommand);
+ position = 0;
}
- c = mycommand[position];
- position++;
+ c = mycommand[position++];
return(c);
} else
#endif
{
- i = safe_read(ap->afile, &c, sizeof(c));
+ do {
+ i = read(ap->afile, &c, sizeof(c));
+ } while (i < 0 && errno == EINTR);
+
return(i == sizeof(c)? c&0177: (closef(ap->afile), 0));
}
}
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