Enhance hold_lock_file_for_{update,append}() API

[thirdparty/git.git] / lockfile.c

diff --git a/lockfile.c b/lockfile.c
index 663f18f9c40145e5ab772021e0c700e9123a4b01..6d756086939b631ab13bf4fcdb8deed2787eed6b 100644 (file)
--- a/lockfile.c
+++ b/lockfile.c
@@ -24,7 +24,7 @@ static void remove_lock_file(void)
 static void remove_lock_file_on_signal(int signo)
 {
        remove_lock_file();
-       signal(SIGINT, SIG_DFL);
+       signal(signo, SIG_DFL);
        raise(signo);
 }
 
@@ -121,20 +121,25 @@ static char *resolve_symlink(char *p, size_t s)
 }
 
 
-static int lock_file(struct lock_file *lk, const char *path)
+static int lock_file(struct lock_file *lk, const char *path, int flags)
 {
-       if (strlen(path) >= sizeof(lk->filename)) return -1;
+       if (strlen(path) >= sizeof(lk->filename))
+               return -1;
        strcpy(lk->filename, path);
        /*
         * subtract 5 from size to make sure there's room for adding
         * ".lock" for the lock file name
         */
-       resolve_symlink(lk->filename, sizeof(lk->filename)-5);
+       if (!(flags & LOCK_NODEREF))
+               resolve_symlink(lk->filename, sizeof(lk->filename)-5);
        strcat(lk->filename, ".lock");
        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);
                        atexit(remove_lock_file);
                }
                lk->owner = getpid();
@@ -152,14 +157,42 @@ static int lock_file(struct lock_file *lk, const char *path)
        return lk->fd;
 }
 
-int hold_lock_file_for_update(struct lock_file *lk, const char *path, int die_on_error)
+int hold_lock_file_for_update(struct lock_file *lk, const char *path, int flags)
 {
-       int fd = lock_file(lk, path);
-       if (fd < 0 && die_on_error)
+       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));
        return fd;
 }
 
+int hold_lock_file_for_append(struct lock_file *lk, const char *path, int flags)
+{
+       int fd, orig_fd;
+
+       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));
+               return fd;
+       }
+
+       orig_fd = open(path, O_RDONLY);
+       if (orig_fd < 0) {
+               if (errno != ENOENT) {
+                       if (flags & LOCK_DIE_ON_ERROR)
+                               die("cannot open '%s' for copying", path);
+                       close(fd);
+                       return error("cannot open '%s' for copying", path);
+               }
+       } else if (copy_fd(orig_fd, fd)) {
+               if (flags & LOCK_DIE_ON_ERROR)
+                       exit(128);
+               close(fd);
+               return -1;
+       }
+       return fd;
+}
+
 int close_lock_file(struct lock_file *lk)
 {
        int fd = lk->fd;
@@ -184,7 +217,10 @@ int commit_lock_file(struct lock_file *lk)
 
 int hold_locked_index(struct lock_file *lk, int die_on_error)
 {
-       return hold_lock_file_for_update(lk, get_index_file(), die_on_error);
+       return hold_lock_file_for_update(lk, get_index_file(),
+                                        die_on_error
+                                        ? LOCK_DIE_ON_ERROR
+                                        : 0);
 }
 
 void set_alternate_index_output(const char *name)