diff options
| -rw-r--r-- | src/signal/raise.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/src/signal/raise.c b/src/signal/raise.c index 52f8b428..f437d23f 100644 --- a/src/signal/raise.c +++ b/src/signal/raise.c @@ -1,7 +1,18 @@ #include <signal.h> +#include <errno.h> #include "syscall.h" int raise(int sig) { - return __syscall_kill(__syscall_getpid(), sig); + int pid, tid, ret; + /* Getting the pid/tid pair is not atomic, and could give wrong + * result if a fork occurs in a signal handler between the two + * syscalls. Use the tgkill syscall's ESRCH semantics to detect + * this condition and retry. */ + do { + tid = syscall0(__NR_gettid); + pid = syscall0(__NR_getpid); + ret = syscall3(__NR_tgkill, pid, tid, sig); + } while (ret<0 && errno == ESRCH); + return ret; } |