prune: clean .git/shallow after pruning objects

This patch teaches "prune" to remove shallow roots that are no longer
reachable from any refs (e.g. when the relevant refs are removed).

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/git-prune.txt b/Documentation/git-prune.txt
index bf824108c116a34972d1dacf1e9fb77db097b2c5..058ac0dc854bfd55a13dd0776beaf36b37e8b8a9 100644 (file)
--- a/Documentation/git-prune.txt
+++ b/Documentation/git-prune.txt
@@ -24,6 +24,8 @@ objects unreachable from any of these head objects from the object database.
 In addition, it
 prunes the unpacked objects that are also found in packs by
 running 'git prune-packed'.
+It also removes entries from .git/shallow that are not reachable by
+any ref.
 
 Note that unreachable, packed objects will remain.  If this is
 not desired, see linkgit:git-repack[1].

diff --git a/builtin/gc.c b/builtin/gc.c
index c14190f840b0427820ebf69b209d86f0a21c62b7..cec8ecd75442e1721ab49be8a4d72b43ce244008 100644 (file)
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -16,6 +16,7 @@
 #include "run-command.h"
 #include "sigchain.h"
 #include "argv-array.h"
+#include "commit.h"
 
 #define FAILED_RUN "failed to run %s"
 

diff --git a/builtin/prune.c b/builtin/prune.c
index 6366917c6de55e171a7f697b22f1de10293addf5..221404034995ba2fa4bb113c4015cc7eb5b01c75 100644 (file)
--- a/builtin/prune.c
+++ b/builtin/prune.c
@@ -170,5 +170,9 @@ int cmd_prune(int argc, const char **argv, const char *prefix)
        s = mkpathdup("%s/pack", get_object_directory());
        remove_temporary_files(s);
        free(s);
+
+       if (is_repository_shallow())
+               prune_shallow(show_only);
+
        return 0;
 }

diff --git a/commit.h b/commit.h
index a1f2d49433be06786adac0dd8bee613c42404e98..affe21033707fcf58552f30c37ed2333d812fde5 100644 (file)
--- a/commit.h
+++ b/commit.h
@@ -235,6 +235,7 @@ extern void assign_shallow_commits_to_refs(struct shallow_info *info,
                                           uint32_t **used,
                                           int *ref_status);
 extern int delayed_reachability_test(struct shallow_info *si, int c);
+extern void prune_shallow(int show_only);
 
 int is_descendant_of(struct commit *, struct commit_list *);
 int in_merge_bases(struct commit *, struct commit *);

diff --git a/shallow.c b/shallow.c
index 3c36dd82bc118d78b60832a80df5a2abb6a0d0d8..c766fc30122e07bfb3da937b9ae9effcf1133206 100644 (file)
--- a/shallow.c
+++ b/shallow.c
@@ -155,10 +155,14 @@ void check_shallow_file_for_update(void)
                die("shallow file was changed during fetch");
 }
 
+#define SEEN_ONLY 1
+#define VERBOSE   2
+
 struct write_shallow_data {
        struct strbuf *out;
        int use_pack_protocol;
        int count;
+       unsigned flags;
 };
 
 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
@@ -167,6 +171,15 @@ static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
        const char *hex = sha1_to_hex(graft->sha1);
        if (graft->nr_parent != -1)
                return 0;
+       if (data->flags & SEEN_ONLY) {
+               struct commit *c = lookup_commit(graft->sha1);
+               if (!c || !(c->object.flags & SEEN)) {
+                       if (data->flags & VERBOSE)
+                               printf("Removing %s from .git/shallow\n",
+                                      sha1_to_hex(c->object.sha1));
+                       return 0;
+               }
+       }
        data->count++;
        if (data->use_pack_protocol)
                packet_buf_write(data->out, "shallow %s", hex);
@@ -177,14 +190,16 @@ static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
        return 0;
 }
 
-int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
-                         const struct sha1_array *extra)
+static int write_shallow_commits_1(struct strbuf *out, int use_pack_protocol,
+                                  const struct sha1_array *extra,
+                                  unsigned flags)
 {
        struct write_shallow_data data;
        int i;
        data.out = out;
        data.use_pack_protocol = use_pack_protocol;
        data.count = 0;
+       data.flags = flags;
        for_each_commit_graft(write_one_shallow, &data);
        if (!extra)
                return data.count;
@@ -196,6 +211,12 @@ int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
        return data.count;
 }
 
+int write_shallow_commits(struct strbuf *out, int use_pack_protocol,
+                         const struct sha1_array *extra)
+{
+       return write_shallow_commits_1(out, use_pack_protocol, extra, 0);
+}
+
 char *setup_temporary_shallow(const struct sha1_array *extra)
 {
        struct strbuf sb = STRBUF_INIT;
@@ -258,6 +279,36 @@ void advertise_shallow_grafts(int fd)
        for_each_commit_graft(advertise_shallow_grafts_cb, &fd);
 }
 
+/*
+ * mark_reachable_objects() should have been run prior to this and all
+ * reachable commits marked as "SEEN".
+ */
+void prune_shallow(int show_only)
+{
+       static struct lock_file shallow_lock;
+       struct strbuf sb = STRBUF_INIT;
+       int fd;
+
+       if (show_only) {
+               write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY | VERBOSE);
+               strbuf_release(&sb);
+               return;
+       }
+       check_shallow_file_for_update();
+       fd = hold_lock_file_for_update(&shallow_lock, git_path("shallow"),
+                                      LOCK_DIE_ON_ERROR);
+       if (write_shallow_commits_1(&sb, 0, NULL, SEEN_ONLY)) {
+               if (write_in_full(fd, sb.buf, sb.len) != sb.len)
+                       die_errno("failed to write to %s",
+                                 shallow_lock.filename);
+               commit_lock_file(&shallow_lock);
+       } else {
+               unlink(git_path("shallow"));
+               rollback_lock_file(&shallow_lock);
+       }
+       strbuf_release(&sb);
+}
+
 #define TRACE_KEY "GIT_TRACE_SHALLOW"
 
 /*

diff --git a/t/t5304-prune.sh b/t/t5304-prune.sh
index e4bb3a14570780b41ce4ebea9e47870d4cbcb127..66c9a41739e5d75633a239c55fd516341f8a98e3 100755 (executable)
--- a/t/t5304-prune.sh
+++ b/t/t5304-prune.sh
@@ -221,4 +221,14 @@ EOF
        test_cmp expected actual
 '
 
+test_expect_success 'prune .git/shallow' '
+       SHA1=`echo hi|git commit-tree HEAD^{tree}` &&
+       echo $SHA1 >.git/shallow &&
+       git prune --dry-run >out &&
+       grep $SHA1 .git/shallow &&
+       grep $SHA1 out &&
+       git prune &&
+       ! test -f .git/shallow
+'
+
 test_done