Make git prune remove temporary packs that look like write failures

Write errors when repacking (eg, due to out-of-space conditions)
can leave temporary packs (and possibly other files beginning
with "tmp_") lying around which no existing
codepath removes and which aren't obvious to the casual user.
These can also be multi-megabyte files wasting noticeable space.
Unfortunately there's no way to definitely tell in builtin-prune
that a tmp_ file is not being used by a concurrent process,
such as a fetch. However, it is documented that pruning should
only be done on a quiet repository and --expire is honoured
(using code from Johannes Schindelin, along with a test case
he wrote) so that its safety is the same as that of loose
object pruning.

Since they might be signs of a problem (unlike orphaned loose
objects) the names of any removed files are printed.

Signed-off-by: David Tweed (david.tweed@gmail.com)
Acked-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-prune.c b/builtin-prune.c
index b5e768421ba548efaf0dd62ca876c15911df55d2..bb8ead92cf41c3cbdbc421a1490fb40ce19f11c3 100644 (file)
--- a/builtin-prune.c
+++ b/builtin-prune.c
@@ -83,6 +83,44 @@ static void prune_object_dir(const char *path)
        }
 }
 
+/*
+ * Write errors (particularly out of space) can result in
+ * failed temporary packs (and more rarely indexes and other
+ * files begining with "tmp_") accumulating in the
+ * object directory.
+ */
+static void remove_temporary_files(void)
+{
+       DIR *dir;
+       struct dirent *de;
+       char* dirname=get_object_directory();
+
+       dir = opendir(dirname);
+       if (!dir) {
+               fprintf(stderr, "Unable to open object directory %s\n",
+                       dirname);
+               return;
+       }
+       while ((de = readdir(dir)) != NULL) {
+               if (!prefixcmp(de->d_name, "tmp_")) {
+                       char name[PATH_MAX];
+                       int c = snprintf(name, PATH_MAX, "%s/%s",
+                                        dirname, de->d_name);
+                       if (c < 0 || c >= PATH_MAX)
+                               continue;
+                       if (expire) {
+                               struct stat st;
+                               if (stat(name, &st) != 0 || st.st_mtime >= expire)
+                                       continue;
+                       }
+                       printf("Removing stale temporary file %s\n", name);
+                       if (!show_only)
+                               unlink(name);
+               }
+       }
+       closedir(dir);
+}
+
 int cmd_prune(int argc, const char **argv, const char *prefix)
 {
        int i;
@@ -115,5 +153,6 @@ int cmd_prune(int argc, const char **argv, const char *prefix)
 
        sync();
        prune_packed_objects(show_only);
+       remove_temporary_files();
        return 0;
 }

diff --git a/t/t5304-prune.sh b/t/t5304-prune.sh
new file mode 100644 (file)
index 0000000..6560af7
--- /dev/null
+++ b/t/t5304-prune.sh
@@ -0,0 +1,32 @@
+#!/bin/sh
+#
+# Copyright (c) 2008 Johannes E. Schindelin
+#
+
+test_description='prune'
+. ./test-lib.sh
+
+test_expect_success setup '
+
+       : > file &&
+       git add file &&
+       test_tick &&
+       git commit -m initial &&
+       git gc
+
+'
+
+test_expect_success 'prune stale packs' '
+
+       orig_pack=$(echo .git/objects/pack/*.pack) &&
+       : > .git/objects/tmp_1.pack &&
+       : > .git/objects/tmp_2.pack &&
+       test-chmtime -86501 .git/objects/tmp_1.pack &&
+       git prune --expire 1.day &&
+       test -f $orig_pack &&
+       test -f .git/objects/tmp_2.pack &&
+       ! test -f .git/objects/tmp_1.pack
+
+'
+
+test_done