git/shallow.c
Nguyễn Thái Ngọc Duy 6035d6aad8 fetch-pack: prepare updated shallow file before fetching the pack
index-pack --strict looks up and follows parent commits. If shallow
information is not ready by the time index-pack is run, index-pack may
be led to non-existent objects. Make fetch-pack save shallow file to
disk before invoking index-pack.

git learns new global option --shallow-file to pass on the alternate
shallow file path. Undocumented (and not even support --shallow-file=
syntax) because it's unlikely to be used again elsewhere.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-05-28 08:06:08 -07:00

149 lines
3.5 KiB
C

#include "cache.h"
#include "commit.h"
#include "tag.h"
static int is_shallow = -1;
static struct stat shallow_stat;
static char *alternate_shallow_file;
void set_alternate_shallow_file(const char *path)
{
if (is_shallow != -1)
die("BUG: is_repository_shallow must not be called before set_alternate_shallow_file");
free(alternate_shallow_file);
alternate_shallow_file = path ? xstrdup(path) : NULL;
}
int register_shallow(const unsigned char *sha1)
{
struct commit_graft *graft =
xmalloc(sizeof(struct commit_graft));
struct commit *commit = lookup_commit(sha1);
hashcpy(graft->sha1, sha1);
graft->nr_parent = -1;
if (commit && commit->object.parsed)
commit->parents = NULL;
return register_commit_graft(graft, 0);
}
int is_repository_shallow(void)
{
FILE *fp;
char buf[1024];
const char *path = alternate_shallow_file;
if (is_shallow >= 0)
return is_shallow;
if (!path)
path = git_path("shallow");
/*
* fetch-pack sets '--shallow-file ""' as an indicator that no
* shallow file should be used. We could just open it and it
* will likely fail. But let's do an explicit check instead.
*/
if (!*path ||
stat(path, &shallow_stat) ||
(fp = fopen(path, "r")) == NULL) {
is_shallow = 0;
return is_shallow;
}
is_shallow = 1;
while (fgets(buf, sizeof(buf), fp)) {
unsigned char sha1[20];
if (get_sha1_hex(buf, sha1))
die("bad shallow line: %s", buf);
register_shallow(sha1);
}
fclose(fp);
return is_shallow;
}
struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
int shallow_flag, int not_shallow_flag)
{
int i = 0, cur_depth = 0;
struct commit_list *result = NULL;
struct object_array stack = OBJECT_ARRAY_INIT;
struct commit *commit = NULL;
while (commit || i < heads->nr || stack.nr) {
struct commit_list *p;
if (!commit) {
if (i < heads->nr) {
commit = (struct commit *)
deref_tag(heads->objects[i++].item, NULL, 0);
if (!commit || commit->object.type != OBJ_COMMIT) {
commit = NULL;
continue;
}
if (!commit->util)
commit->util = xmalloc(sizeof(int));
*(int *)commit->util = 0;
cur_depth = 0;
} else {
commit = (struct commit *)
stack.objects[--stack.nr].item;
cur_depth = *(int *)commit->util;
}
}
if (parse_commit(commit))
die("invalid commit");
cur_depth++;
if (cur_depth >= depth) {
commit_list_insert(commit, &result);
commit->object.flags |= shallow_flag;
commit = NULL;
continue;
}
commit->object.flags |= not_shallow_flag;
for (p = commit->parents, commit = NULL; p; p = p->next) {
if (!p->item->util) {
int *pointer = xmalloc(sizeof(int));
p->item->util = pointer;
*pointer = cur_depth;
} else {
int *pointer = p->item->util;
if (cur_depth >= *pointer)
continue;
*pointer = cur_depth;
}
if (cur_depth < depth) {
if (p->next)
add_object_array(&p->item->object,
NULL, &stack);
else {
commit = p->item;
cur_depth = *(int *)commit->util;
}
} else {
commit_list_insert(p->item, &result);
p->item->object.flags |= shallow_flag;
}
}
}
return result;
}
void check_shallow_file_for_update(void)
{
struct stat st;
if (!is_shallow)
return;
else if (is_shallow == -1)
die("BUG: shallow must be initialized by now");
if (stat(git_path("shallow"), &st))
die("shallow file was removed during fetch");
else if (st.st_mtime != shallow_stat.st_mtime
#ifdef USE_NSEC
|| ST_MTIME_NSEC(st) != ST_MTIME_NSEC(shallow_stat)
#endif
)
die("shallow file was changed during fetch");
}