push: fix segfault for odd config

diff --git a/lockfile.c b/lockfile.c
index 8589155532da9eb7f42a1e9c3132fcf42b1b9275..3dbb2d1ff9407a7417be294adedc5312e7421a96 100644 (file)
--- a/lockfile.c
+++ b/lockfile.c
@@ -2,6 +2,7 @@
  * Copyright (c) 2005, Junio C Hamano
  */
 #include "cache.h"
+#include "sigchain.h"
 
 static struct lock_file *lock_file_list;
 static const char *alternate_index_output;
@@ -24,7 +25,7 @@ static void remove_lock_file(void)
 static void remove_lock_file_on_signal(int signo)
 {
        remove_lock_file();
-       signal(signo, SIG_DFL);
+       sigchain_pop(signo);
        raise(signo);
 }
 
@@ -136,11 +137,7 @@ static int lock_file(struct lock_file *lk, const char *path, int flags)
        lk->fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
        if (0 <= lk->fd) {
                if (!lock_file_list) {
-                       signal(SIGINT, remove_lock_file_on_signal);
-                       signal(SIGHUP, remove_lock_file_on_signal);
-                       signal(SIGTERM, remove_lock_file_on_signal);
-                       signal(SIGQUIT, remove_lock_file_on_signal);
-                       signal(SIGPIPE, remove_lock_file_on_signal);
+                       sigchain_push_common(remove_lock_file_on_signal);
                        atexit(remove_lock_file);
                }
                lk->owner = getpid();
@@ -158,11 +155,25 @@ static int lock_file(struct lock_file *lk, const char *path, int flags)
        return lk->fd;
 }
 
+
+NORETURN void unable_to_lock_index_die(const char *path, int err)
+{
+       if (err == EEXIST) {
+               die("Unable to create '%s.lock': %s.\n\n"
+                   "If no other git process is currently running, this probably means a\n"
+                   "git process crashed in this repository earlier. Make sure no other git\n"
+                   "process is running and remove the file manually to continue.",
+                   path, strerror(err));
+       } else {
+               die("Unable to create '%s.lock': %s", path, strerror(err));
+       }
+}
+
 int hold_lock_file_for_update(struct lock_file *lk, const char *path, int flags)
 {
        int fd = lock_file(lk, path, flags);
        if (fd < 0 && (flags & LOCK_DIE_ON_ERROR))
-               die("unable to create '%s.lock': %s", path, strerror(errno));
+               unable_to_lock_index_die(path, errno);
        return fd;
 }
 
@@ -173,7 +184,7 @@ int hold_lock_file_for_append(struct lock_file *lk, const char *path, int flags)
        fd = lock_file(lk, path, flags);
        if (fd < 0) {
                if (flags & LOCK_DIE_ON_ERROR)
-                       die("unable to create '%s.lock': %s", path, strerror(errno));
+                       unable_to_lock_index_die(path, errno);
                return fd;
        }