rev-parse: document --is-inside-git-dir
[gitweb.git] / lockfile.c
index 9bc60837aa12fbe2e659ff6fb5b52e862fbe03c3..23db35aff21d7c33197726128e2f120291e6e9f0 100644 (file)
@@ -1,15 +1,18 @@
 /*
  * Copyright (c) 2005, Junio C Hamano
  */
-#include <signal.h>
 #include "cache.h"
 
 static struct lock_file *lock_file_list;
+static const char *alternate_index_output;
 
 static void remove_lock_file(void)
 {
+       pid_t me = getpid();
+
        while (lock_file_list) {
-               if (lock_file_list->filename[0])
+               if (lock_file_list->owner == me &&
+                   lock_file_list->filename[0])
                        unlink(lock_file_list->filename);
                lock_file_list = lock_file_list->next;
        }
@@ -22,17 +25,36 @@ static void remove_lock_file_on_signal(int signo)
        raise(signo);
 }
 
-int hold_lock_file_for_update(struct lock_file *lk, const char *path)
+static int lock_file(struct lock_file *lk, const char *path)
 {
        int fd;
        sprintf(lk->filename, "%s.lock", path);
        fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
-       if (fd >=0 && !lk->next) {
-               lk->next = lock_file_list;
-               lock_file_list = lk;
-               signal(SIGINT, remove_lock_file_on_signal);
-               atexit(remove_lock_file);
+       if (0 <= fd) {
+               lk->owner = getpid();
+               if (!lk->on_list) {
+                       lk->next = lock_file_list;
+                       lock_file_list = lk;
+                       lk->on_list = 1;
+               }
+               if (lock_file_list) {
+                       signal(SIGINT, remove_lock_file_on_signal);
+                       atexit(remove_lock_file);
+               }
+               if (adjust_shared_perm(lk->filename))
+                       return error("cannot fix permission bits on %s",
+                                    lk->filename);
        }
+       else
+               lk->filename[0] = 0;
+       return fd;
+}
+
+int hold_lock_file_for_update(struct lock_file *lk, const char *path, int die_on_error)
+{
+       int fd = lock_file(lk, path);
+       if (fd < 0 && die_on_error)
+               die("unable to create '%s.lock': %s", path, strerror(errno));
        return fd;
 }
 
@@ -48,6 +70,27 @@ int commit_lock_file(struct lock_file *lk)
        return i;
 }
 
+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);
+}
+
+void set_alternate_index_output(const char *name)
+{
+       alternate_index_output = name;
+}
+
+int commit_locked_index(struct lock_file *lk)
+{
+       if (alternate_index_output) {
+               int result = rename(lk->filename, alternate_index_output);
+               lk->filename[0] = 0;
+               return result;
+       }
+       else
+               return commit_lock_file(lk);
+}
+
 void rollback_lock_file(struct lock_file *lk)
 {
        if (lk->filename[0])