1#include "cache.h"
2#include "refs.h"
3#include "tag.h"
4#include "pack-refs.h"
5
6struct ref_to_prune {
7 struct ref_to_prune *next;
8 unsigned char sha1[20];
9 char name[FLEX_ARRAY];
10};
11
12struct pack_refs_cb_data {
13 unsigned int flags;
14 struct ref_to_prune *ref_to_prune;
15 FILE *refs_file;
16};
17
18static int do_not_prune(int flags)
19{
20 /* If it is already packed or if it is a symref,
21 * do not prune it.
22 */
23 return (flags & (REF_ISSYMREF|REF_ISPACKED));
24}
25
26static int handle_one_ref(const char *path, const unsigned char *sha1,
27 int flags, void *cb_data)
28{
29 struct pack_refs_cb_data *cb = cb_data;
30 int is_tag_ref;
31
32 /* Do not pack the symbolic refs */
33 if ((flags & REF_ISSYMREF))
34 return 0;
35 is_tag_ref = !prefixcmp(path, "refs/tags/");
36
37 /* ALWAYS pack refs that were already packed or are tags */
38 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref && !(flags & REF_ISPACKED))
39 return 0;
40
41 fprintf(cb->refs_file, "%s %s\n", sha1_to_hex(sha1), path);
42 if (is_tag_ref) {
43 struct object *o = parse_object(sha1);
44 if (o->type == OBJ_TAG) {
45 o = deref_tag(o, path, 0);
46 if (o)
47 fprintf(cb->refs_file, "^%s\n",
48 sha1_to_hex(o->sha1));
49 }
50 }
51
52 if ((cb->flags & PACK_REFS_PRUNE) && !do_not_prune(flags)) {
53 int namelen = strlen(path) + 1;
54 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
55 hashcpy(n->sha1, sha1);
56 strcpy(n->name, path);
57 n->next = cb->ref_to_prune;
58 cb->ref_to_prune = n;
59 }
60 return 0;
61}
62
63/* make sure nobody touched the ref, and unlink */
64static void prune_ref(struct ref_to_prune *r)
65{
66 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
67
68 if (lock) {
69 unlink_or_warn(git_path("%s", r->name));
70 unlock_ref(lock);
71 }
72}
73
74static void prune_refs(struct ref_to_prune *r)
75{
76 while (r) {
77 prune_ref(r);
78 r = r->next;
79 }
80}
81
82static struct lock_file packed;
83
84int pack_refs(unsigned int flags)
85{
86 int fd;
87 struct pack_refs_cb_data cbdata;
88
89 memset(&cbdata, 0, sizeof(cbdata));
90 cbdata.flags = flags;
91
92 fd = hold_lock_file_for_update(&packed, git_path("packed-refs"),
93 LOCK_DIE_ON_ERROR);
94 cbdata.refs_file = fdopen(fd, "w");
95 if (!cbdata.refs_file)
96 die_errno("unable to create ref-pack file structure");
97
98 /* perhaps other traits later as well */
99 fprintf(cbdata.refs_file, "# pack-refs with: peeled \n");
100
101 for_each_ref(handle_one_ref, &cbdata);
102 if (ferror(cbdata.refs_file))
103 die("failed to write ref-pack file");
104 if (fflush(cbdata.refs_file) || fsync(fd) || fclose(cbdata.refs_file))
105 die_errno("failed to write ref-pack file");
106 /*
107 * Since the lock file was fdopen()'ed and then fclose()'ed above,
108 * assign -1 to the lock file descriptor so that commit_lock_file()
109 * won't try to close() it.
110 */
111 packed.fd = -1;
112 if (commit_lock_file(&packed) < 0)
113 die_errno("unable to overwrite old ref-pack file");
114 if (cbdata.flags & PACK_REFS_PRUNE)
115 prune_refs(cbdata.ref_to_prune);
116 return 0;
117}