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authorDenys Vlasenko <vda.linux@googlemail.com>2011-05-08 22:52:15 (GMT)
committer Denys Vlasenko <vda.linux@googlemail.com>2011-05-08 22:52:15 (GMT)
commit54e9e1217c67563d70d6e2b14021293f707d7927 (patch)
treef8cd7fe165e7ac70eef901330fb7f95db68dbdd1
parent80542bad2f1df9d99b579c9eeb3c2675c14c72c0 (diff)
downloadbusybox-54e9e1217c67563d70d6e2b14021293f707d7927.tar.gz
busybox-54e9e1217c67563d70d6e2b14021293f707d7927.tar.bz2
hush: code shrink
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--shell/hush.c125
1 files changed, 66 insertions, 59 deletions
diff --git a/shell/hush.c b/shell/hush.c
index 0b17b22..71972f7 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -1379,6 +1379,11 @@ enum {
#endif
};
+static void sigprocmask_set(sigset_t *set)
+{
+ sigprocmask(SIG_SETMASK, set, NULL);
+}
+
#if ENABLE_HUSH_FAST
static void SIGCHLD_handler(int sig UNUSED_PARAM)
{
@@ -5378,18 +5383,15 @@ static void reset_traps_to_defaults(void)
* Stupid. It can be done with *single* &= op, but we can't use
* the fact that G.blocked_set is implemented as a bitmask
* in libc... */
- mask = (SPECIAL_INTERACTIVE_SIGS >> 1);
- sig = 1;
- while (1) {
+ mask = SPECIAL_INTERACTIVE_SIGS;
+ sig = 0;
+ while ((mask >>= 1) != 0) {
+ sig++;
if (mask & 1) {
/* Careful. Only if no trap or trap is not "" */
if (!G.traps || !G.traps[sig] || G.traps[sig][0])
sigdelset(&G.blocked_set, sig);
}
- mask >>= 1;
- if (!mask)
- break;
- sig++;
}
/* Our homegrown sig mask is saner to work with :) */
G.non_DFL_mask &= ~SPECIAL_INTERACTIVE_SIGS;
@@ -5411,7 +5413,7 @@ static void reset_traps_to_defaults(void)
continue;
sigdelset(&G.blocked_set, sig);
}
- sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
+ sigprocmask_set(&G.blocked_set);
}
#else /* !BB_MMU */
@@ -5541,7 +5543,7 @@ static void re_execute_shell(char ***to_free, const char *s,
do_exec:
debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s);
- sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
+ sigprocmask_set(&G.inherited_set);
execve(bb_busybox_exec_path, argv, pp);
/* Fallback. Useful for init=/bin/hush usage etc */
if (argv[0][0] == '/')
@@ -6195,7 +6197,7 @@ 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);
+ sigprocmask_set(&G.inherited_set);
execvp(argv[0], argv);
bb_perror_msg("can't execute '%s'", argv[0]);
_exit(127); /* bash compat */
@@ -6327,7 +6329,7 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
# endif
/* Re-exec ourselves */
debug_printf_exec("re-execing applet '%s'\n", argv[0]);
- sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
+ sigprocmask_set(&G.inherited_set);
execv(bb_busybox_exec_path, argv);
/* If they called chroot or otherwise made the binary no longer
* executable, fall through */
@@ -7435,84 +7437,89 @@ static void init_sigmasks(void)
{
unsigned sig;
unsigned mask;
- sigset_t old_blocked_set;
+ /* POSIX allows shell to re-enable SIGCHLD
+ * even if it was SIG_IGN on entry */
+#if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */
+#endif
if (!G.inherited_set_is_saved) {
+#if ENABLE_HUSH_FAST
+ signal(SIGCHLD, SIGCHLD_handler);
+#else
+ signal(SIGCHLD, SIG_DFL);
+#endif
sigprocmask(SIG_SETMASK, NULL, &G.blocked_set);
G.inherited_set = G.blocked_set;
}
- old_blocked_set = G.blocked_set;
+ /* Which signals are shell-special? */
mask = (1 << SIGQUIT);
if (G_interactive_fd) {
- mask = (1 << SIGQUIT) | SPECIAL_INTERACTIVE_SIGS;
+ mask |= SPECIAL_INTERACTIVE_SIGS;
if (G_saved_tty_pgrp) /* we have ctty, job control sigs work */
mask |= SPECIAL_JOB_SIGS;
}
G.non_DFL_mask = mask;
+ /* Block them. And unblock SIGCHLD */
sig = 0;
- while (mask) {
+ while ((mask >>= 1) != 0) {
+ sig++;
if (mask & 1)
sigaddset(&G.blocked_set, sig);
- mask >>= 1;
- sig++;
}
sigdelset(&G.blocked_set, SIGCHLD);
- if (memcmp(&old_blocked_set, &G.blocked_set, sizeof(old_blocked_set)) != 0)
- sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
-
- /* POSIX allows shell to re-enable SIGCHLD
- * even if it was SIG_IGN on entry */
-#if ENABLE_HUSH_FAST
- G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */
- if (!G.inherited_set_is_saved)
- signal(SIGCHLD, SIGCHLD_handler);
-#else
- if (!G.inherited_set_is_saved)
- signal(SIGCHLD, SIG_DFL);
-#endif
+ if (memcmp(&G.inherited_set, &G.blocked_set, sizeof(G.inherited_set)) != 0)
+ sigprocmask_set(&G.blocked_set);
G.inherited_set_is_saved = 1;
}
#if ENABLE_HUSH_JOB
/* helper */
-static void maybe_set_to_sigexit(int sig)
+/* Set handlers to restore tty pgrp and exit */
+static void set_fatal_handlers_to_sigexit(void)
{
void (*handler)(int);
+ unsigned fatal_sigs, sig;
+
+ /* We will restore tty pgrp on these signals */
+ fatal_sigs = 0
+ + (1 << SIGILL ) * HUSH_DEBUG
+ + (1 << SIGFPE ) * HUSH_DEBUG
+ + (1 << SIGBUS ) * HUSH_DEBUG
+ + (1 << SIGSEGV) * HUSH_DEBUG
+ + (1 << SIGTRAP) * HUSH_DEBUG
+ + (1 << SIGABRT)
+ /* bash 3.2 seems to handle these just like 'fatal' ones */
+ + (1 << SIGPIPE)
+ + (1 << SIGALRM)
+ /* if we are interactive, SIGHUP, SIGTERM and SIGINT are masked.
+ * if we aren't interactive... but in this case
+ * we never want to restore pgrp on exit, and this fn is not called */
+ /*+ (1 << SIGHUP )*/
+ /*+ (1 << SIGTERM)*/
+ /*+ (1 << SIGINT )*/
+ ;
+
/* non_DFL_mask'ed signals are, well, masked,
* no need to set handler for them.
*/
- if (!((G.non_DFL_mask >> sig) & 1)) {
+ fatal_sigs &= ~G.non_DFL_mask;
+
+ /* For each sig in fatal_sigs... */
+ sig = 0;
+ while ((fatal_sigs >>= 1) != 0) {
+ sig++;
+ if (!(fatal_sigs & 1))
+ continue;
handler = signal(sig, sigexit);
if (handler == SIG_IGN) /* oops... restore back to IGN! */
signal(sig, handler);
}
}
-/* Set handlers to restore tty pgrp and exit */
-static void set_fatal_handlers(void)
-{
- /* We _must_ restore tty pgrp on fatal signals */
- if (HUSH_DEBUG) {
- maybe_set_to_sigexit(SIGILL );
- maybe_set_to_sigexit(SIGFPE );
- maybe_set_to_sigexit(SIGBUS );
- maybe_set_to_sigexit(SIGSEGV);
- maybe_set_to_sigexit(SIGTRAP);
- } /* else: hush is perfect. what SEGV? */
- maybe_set_to_sigexit(SIGABRT);
- /* bash 3.2 seems to handle these just like 'fatal' ones */
- maybe_set_to_sigexit(SIGPIPE);
- maybe_set_to_sigexit(SIGALRM);
- /* if we are interactive, SIGHUP, SIGTERM and SIGINT are masked.
- * if we aren't interactive... but in this case
- * we never want to restore pgrp on exit, and this fn is not called */
- /*maybe_set_to_sigexit(SIGHUP );*/
- /*maybe_set_to_sigexit(SIGTERM);*/
- /*maybe_set_to_sigexit(SIGINT );*/
-}
#endif
static int set_mode(int state, char mode, const char *o_opt)
@@ -7769,7 +7776,7 @@ int hush_main(int argc, char **argv)
sigaddset(&G.blocked_set, sig);
}
}
- sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
+ sigprocmask_set(&G.blocked_set);
}
# if ENABLE_HUSH_LOOPS
optarg++;
@@ -7910,7 +7917,7 @@ int hush_main(int argc, char **argv)
if (G_saved_tty_pgrp) {
/* Set other signals to restore saved_tty_pgrp */
- set_fatal_handlers();
+ set_fatal_handlers_to_sigexit();
/* Put ourselves in our own process group
* (bash, too, does this only if ctty is available) */
bb_setpgrp(); /* is the same as setpgid(our_pid, our_pid); */
@@ -8301,7 +8308,7 @@ static int FAST_FUNC builtin_trap(char **argv)
sigdelset(&G.blocked_set, sig);
}
}
- sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
+ sigprocmask_set(&G.blocked_set);
return ret;
}
@@ -8858,7 +8865,7 @@ static int FAST_FUNC builtin_wait(char **argv)
* $
*/
sigaddset(&G.blocked_set, SIGCHLD);
- sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
+ sigprocmask_set(&G.blocked_set);
while (1) {
checkjobs(NULL);
if (errno == ECHILD)
@@ -8875,7 +8882,7 @@ static int FAST_FUNC builtin_wait(char **argv)
}
}
sigdelset(&G.blocked_set, SIGCHLD);
- sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
+ sigprocmask_set(&G.blocked_set);
return ret;
}