Fix Solaris stdio signal handling stupidities

This uses sigaction() to install the SIGALRM handler with SA_RESTART, so
that Solaris stdio doesn't break completely when a signal interrupts a
read.

Thanks to Jason Riedy for confirming the silly Solaris signal behaviour.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/pack-objects.c b/pack-objects.c
index 8f352aa..cde4afa 100644 (file)
--- a/pack-objects.c
+++ b/pack-objects.c
@@ -53,7 +53,7 @@ static int nr_objects = 0, nr_alloc = 0;
 static const char *base_name;
 static unsigned char pack_file_sha1[20];
 static int progress = 1;
-static volatile int progress_update = 0;
+static volatile sig_atomic_t progress_update = 0;
 
 /*
  * The object names in objects array are hashed with this hashtable,
@@ -685,7 +685,6 @@ static int try_delta(struct unpacked *cur, struct unpacked *old, unsigned max_de
 
 static void progress_interval(int signum)
 {
-       signal(SIGALRM, progress_interval);
        progress_update = 1;
 }
 
@@ -820,6 +819,23 @@ static int reuse_cached_pack(unsigned char *sha1, int pack_to_stdout)
        return 1;
 }
 
+static void setup_progress_signal(void)
+{
+       struct sigaction sa;
+       struct itimerval v;
+
+       memset(&sa, 0, sizeof(sa));
+       sa.sa_handler = progress_interval;
+       sigemptyset(&sa.sa_mask);
+       sa.sa_flags = SA_RESTART;
+       sigaction(SIGALRM, &sa, NULL);
+
+       v.it_interval.tv_sec = 1;
+       v.it_interval.tv_usec = 0;
+       v.it_value = v.it_interval;
+       setitimer(ITIMER_REAL, &v, NULL);
+}
+
 int main(int argc, char **argv)
 {
        SHA_CTX ctx;
@@ -885,13 +901,8 @@ int main(int argc, char **argv)
        prepare_packed_git();
 
        if (progress) {
-               struct itimerval v;
-               v.it_interval.tv_sec = 1;
-               v.it_interval.tv_usec = 0;
-               v.it_value = v.it_interval;
-               signal(SIGALRM, progress_interval);
-               setitimer(ITIMER_REAL, &v, NULL);
                fprintf(stderr, "Generating pack...\n");
+               setup_progress_signal();
        }
 
        while (fgets(line, sizeof(line), stdin) != NULL) {