hush: fix exec builtin in a better way (+ "glob in exec" bug fixed)

function                                             old     new   delta
execvp_or_die                                          -      50     +50
static.pseudo_null_str                                 3       -      -3
builtin_exec                                          83      57     -26
pseudo_exec_argv                                     200     163     -37
------------------------------------------------------------------------------
(add/remove: 1/1 grow/shrink: 0/2 up/down: 50/-66)            Total: -16 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2009-10-19 23:09:06 +02:00
parent a8df4c09fb
commit 3ef4f77620
2 changed files with 19 additions and 27 deletions

View File

@ -3322,6 +3322,16 @@ static void exec_builtin(char ***to_free,
}
static void execvp_or_die(char **argv) NORETURN;
static void execvp_or_die(char **argv)
{
debug_printf_exec("execing '%s'\n", argv[0]);
sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
execvp(argv[0], argv);
bb_perror_msg("can't execute '%s'", argv[0]);
_exit(127); /* bash compat */
}
#if BB_MMU
#define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \
pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
@ -3337,7 +3347,7 @@ static void exec_builtin(char ***to_free,
static void pseudo_exec_argv(nommu_save_t *nommu_save,
char **argv, int assignment_cnt,
char **argv_expanded) NORETURN;
static void pseudo_exec_argv(nommu_save_t *nommu_save,
static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
char **argv, int assignment_cnt,
char **argv_expanded)
{
@ -3421,11 +3431,7 @@ static void pseudo_exec_argv(nommu_save_t *nommu_save,
#if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
skip:
#endif
debug_printf_exec("execing '%s'\n", argv[0]);
sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
execvp(argv[0], argv);
bb_perror_msg("can't execute '%s'", argv[0]);
_exit(127); /* bash compat */
execvp_or_die(argv);
}
/* Called after [v]fork() in run_pipe
@ -6985,32 +6991,19 @@ static int FAST_FUNC builtin_cd(char **argv)
static int FAST_FUNC builtin_exec(char **argv)
{
static const char pseudo_null_str[] = { SPECIAL_VAR_SYMBOL, SPECIAL_VAR_SYMBOL, '\0' };
char **pp;
#if !BB_MMU
nommu_save_t dummy;
#endif
if (*++argv == NULL)
return EXIT_SUCCESS; /* bash does this */
/* Make sure empty arguments aren't ignored */
/* Example: exec ls '' */
pp = argv;
while (*pp) {
if ((*pp)[0] == '\0')
*pp = (char*)pseudo_null_str;
pp++;
}
/* Careful: we can end up here after [v]fork. Do not restore
* tty pgrp then, only top-level shell process does that */
if (G_saved_tty_pgrp && getpid() == G.root_pid)
tcsetpgrp(G_interactive_fd, G_saved_tty_pgrp);
/* TODO: if exec fails, bash does NOT exit! We do... */
pseudo_exec_argv(&dummy, argv, 0, NULL);
/* never returns */
/* TODO: if exec fails, bash does NOT exit! We do.
* We'll need to undo sigprocmask (it's inside execvp_or_die)
* and tcsetpgrp, and this is inherently racy.
*/
execvp_or_die(argv);
}
static int FAST_FUNC builtin_exit(char **argv)

View File

@ -1,7 +1,6 @@
if test $# = 0; then
# UNFIXED BUG in builtin_exec! will glob param!
#exec "$THIS_SH" "$0" 'param_glob.t*'
"$THIS_SH" "$0" 'param_glob.t*'
exec "$THIS_SH" "$0" 'param_glob.t*'
echo NOT SHOWN
exit
fi
echo $*