From 3ef4f77620a9f5f9a7c1247e29ea9c14e07b8a30 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Mon, 19 Oct 2009 23:09:06 +0200 Subject: [PATCH] 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 --- shell/hush.c | 41 +++++++++------------- shell/hush_test/hush-vars/param_glob.tests | 5 ++- 2 files changed, 19 insertions(+), 27 deletions(-) diff --git a/shell/hush.c b/shell/hush.c index ae08c7326..5edcdb844 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -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) diff --git a/shell/hush_test/hush-vars/param_glob.tests b/shell/hush_test/hush-vars/param_glob.tests index 0173fd771..4d74fee02 100755 --- a/shell/hush_test/hush-vars/param_glob.tests +++ b/shell/hush_test/hush-vars/param_glob.tests @@ -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 $* -- 2.25.1