diff options
Diffstat (limited to 'signal.c')
-rw-r--r-- | signal.c | 36 |
1 files changed, 35 insertions, 1 deletions
@@ -47,6 +47,11 @@ typedef int rb_atomic_t; # define NSIG (_SIGMAX + 1) /* For QNX */ #endif +#if defined(SIGSEGV) && defined(HAVE_SIGALTSTACK) +#define USE_SIGALTSTACK +int is_altstack_defined = 0; +#endif + static const struct signals { const char *signm; int signo; @@ -410,6 +415,28 @@ static struct { typedef RETSIGTYPE (*sighandler_t)(int); #ifdef POSIX_SIGNAL +#ifdef USE_SIGALTSTACK +#define ALT_STACK_SIZE (4*1024) +/* alternate stack for SIGSEGV */ +static void register_sigaltstack() { + stack_t newSS, oldSS; + + if(is_altstack_defined) + return; + + newSS.ss_sp = malloc(ALT_STACK_SIZE); + if(newSS.ss_sp == NULL) + /* should handle error */ + rb_bug("register_sigaltstack. malloc error\n"); + newSS.ss_size = ALT_STACK_SIZE; + newSS.ss_flags = 0; + + if (sigaltstack(&newSS, &oldSS) < 0) + rb_bug("register_sigaltstack. error\n"); + is_altstack_defined = 1; +} +#endif + static sighandler_t ruby_signal(int signum, sighandler_t handler) { @@ -432,7 +459,12 @@ ruby_signal(int signum, sighandler_t handler) if (signum == SIGCHLD && handler == SIG_IGN) sigact.sa_flags |= SA_NOCLDWAIT; #endif - sigaction(signum, &sigact, &old); +#if defined(SA_ONSTACK) && defined(USE_SIGALTSTACK) + if (signum == SIGSEGV) + sigact.sa_flags |= SA_ONSTACK; +#endif + if (sigaction(signum, &sigact, &old) < 0) + rb_bug("sigaction error.\n"); return old.sa_handler; } @@ -663,6 +695,7 @@ default_handler(int sig) #ifdef SIGSEGV case SIGSEGV: func = sigsegv; + register_sigaltstack(); break; #endif #ifdef SIGPIPE @@ -1070,6 +1103,7 @@ Init_signal(void) install_sighandler(SIGBUS, sigbus); #endif #ifdef SIGSEGV + register_sigaltstack(); install_sighandler(SIGSEGV, sigsegv); #endif } |