Andrew's git - gitweb.git/blob

   1/*
   2 * Copyright (c) 2005, Junio C Hamano
   3 */
   4#include "cache.h"
   5
   6static struct lock_file *lock_file_list;
   7static const char *alternate_index_output;
   8
   9static void remove_lock_file(void)
  10{
  11        while (lock_file_list) {
  12                if (lock_file_list->filename[0])
  13                        unlink(lock_file_list->filename);
  14                lock_file_list = lock_file_list->next;
  15        }
  16}
  17
  18static void remove_lock_file_on_signal(int signo)
  19{
  20        remove_lock_file();
  21        signal(SIGINT, SIG_DFL);
  22        raise(signo);
  23}
  24
  25static int lock_file(struct lock_file *lk, const char *path)
  26{
  27        int fd;
  28        sprintf(lk->filename, "%s.lock", path);
  29        fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
  30        if (0 <= fd) {
  31                if (!lk->on_list) {
  32                        lk->next = lock_file_list;
  33                        lock_file_list = lk;
  34                        lk->on_list = 1;
  35                }
  36                if (lock_file_list) {
  37                        signal(SIGINT, remove_lock_file_on_signal);
  38                        atexit(remove_lock_file);
  39                }
  40                if (adjust_shared_perm(lk->filename))
  41                        return error("cannot fix permission bits on %s",
  42                                     lk->filename);
  43        }
  44        else
  45                lk->filename[0] = 0;
  46        return fd;
  47}
  48
  49int hold_lock_file_for_update(struct lock_file *lk, const char *path, int die_on_error)
  50{
  51        int fd = lock_file(lk, path);
  52        if (fd < 0 && die_on_error)
  53                die("unable to create '%s.lock': %s", path, strerror(errno));
  54        return fd;
  55}
  56
  57int commit_lock_file(struct lock_file *lk)
  58{
  59        char result_file[PATH_MAX];
  60        int i;
  61        strcpy(result_file, lk->filename);
  62        i = strlen(result_file) - 5; /* .lock */
  63        result_file[i] = 0;
  64        i = rename(lk->filename, result_file);
  65        lk->filename[0] = 0;
  66        return i;
  67}
  68
  69int hold_locked_index(struct lock_file *lk, int die_on_error)
  70{
  71        return hold_lock_file_for_update(lk, get_index_file(), die_on_error);
  72}
  73
  74void set_alternate_index_output(const char *name)
  75{
  76        alternate_index_output = name;
  77}
  78
  79int commit_locked_index(struct lock_file *lk)
  80{
  81        if (alternate_index_output) {
  82                int result = rename(lk->filename, alternate_index_output);
  83                lk->filename[0] = 0;
  84                return result;
  85        }
  86        else
  87                return commit_lock_file(lk);
  88}
  89
  90void rollback_lock_file(struct lock_file *lk)
  91{
  92        if (lk->filename[0])
  93                unlink(lk->filename);
  94        lk->filename[0] = 0;
  95}
  96