More friendly message when locking the index fails.

Just saying that index.lock exists doesn't tell the user _what_ to do
to fix the problem. We should give an indication that it's normally
safe to delete index.lock after making sure git isn't running here.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-update-index.c b/builtin-update-index.c
index 65d5775107f9013526cc5b288a80a00b449e8814..daca0f775e4b49f2576a7c444895146d05b7022c 100644 (file)
--- a/builtin-update-index.c
+++ b/builtin-update-index.c
@@ -742,8 +742,7 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
                if (newfd < 0) {
                        if (refresh_flags & REFRESH_QUIET)
                                exit(128);
-                       die("unable to create '%s.lock': %s",
-                           get_index_file(), strerror(lock_error));
+                       unable_to_lock_index_die(get_index_file(), lock_error);
                }
                if (write_cache(newfd, active_cache, active_nr) ||
                    commit_locked_index(lock_file))

diff --git a/cache.h b/cache.h
index 3a33b1e82b0db66fad1e0ce45380c8b847aad15f..0e2f219b2b4d9ff5944e68dbaf2338c76055161f 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -484,6 +484,7 @@ struct lock_file {
 };
 #define LOCK_DIE_ON_ERROR 1
 #define LOCK_NODEREF 2
+extern NORETURN void unable_to_lock_index_die(const char *path, int err);
 extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 extern int hold_lock_file_for_append(struct lock_file *, const char *path, int);
 extern int commit_lock_file(struct lock_file *);

diff --git a/lockfile.c b/lockfile.c
index 8589155532da9eb7f42a1e9c3132fcf42b1b9275..8e556ff8c9671864db44dc8b6f4a861bd35142a6 100644 (file)
--- a/lockfile.c
+++ b/lockfile.c
@@ -158,11 +158,25 @@ 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 (errno == 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;
 }