builtin-pack-refs.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "object.h"
   4 #include "tag.h"
   5
   6 static const char builtin_pack_refs_usage[] =
   7 "git-pack-refs [--all] [--prune]";
   8
   9 struct ref_to_prune {
  10         struct ref_to_prune *next;
  11         unsigned char sha1[20];
  12         char name[FLEX_ARRAY];
  13 };
  14
  15 struct pack_refs_cb_data {
  16         int prune;
  17         int all;
  18         struct ref_to_prune *ref_to_prune;
  19         FILE *refs_file;
  20 };
  21
  22 static int do_not_prune(int flags)
  23 {
  24         /* If it is already packed or if it is a symref,
  25          * do not prune it.
  26          */
  27         return (flags & (REF_ISSYMREF|REF_ISPACKED));
  28 }
  29
  30 static int handle_one_ref(const char *path, const unsigned char *sha1,
  31                           int flags, void *cb_data)
  32 {
  33         struct pack_refs_cb_data *cb = cb_data;
  34         int is_tag_ref;
  35
  36         /* Do not pack the symbolic refs */
  37         if ((flags & REF_ISSYMREF))
  38                 return 0;
  39         is_tag_ref = !strncmp(path, "refs/tags/", 10);
  40         if (!cb->all && !is_tag_ref)
  41                 return 0;
  42
  43         fprintf(cb->refs_file, "%s %s\n", sha1_to_hex(sha1), path);
  44         if (is_tag_ref) {
  45                 struct object *o = parse_object(sha1);
  46                 if (o->type == OBJ_TAG) {
  47                         o = deref_tag(o, path, 0);
  48                         if (o)
  49                                 fprintf(cb->refs_file, "^%s\n",
  50                                         sha1_to_hex(o->sha1));
  51                 }
  52         }
  53
  54         if (cb->prune && !do_not_prune(flags)) {
  55                 int namelen = strlen(path) + 1;
  56                 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
  57                 hashcpy(n->sha1, sha1);
  58                 strcpy(n->name, path);
  59                 n->next = cb->ref_to_prune;
  60                 cb->ref_to_prune = n;
  61         }
  62         return 0;
  63 }
  64
  65 /* make sure nobody touched the ref, and unlink */
  66 static void prune_ref(struct ref_to_prune *r)
  67 {
  68         struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
  69
  70         if (lock) {
  71                 unlink(git_path("%s", r->name));
  72                 unlock_ref(lock);
  73         }
  74 }
  75
  76 static void prune_refs(struct ref_to_prune *r)
  77 {
  78         while (r) {
  79                 prune_ref(r);
  80                 r = r->next;
  81         }
  82 }
  83
  84 static struct lock_file packed;
  85
  86 int cmd_pack_refs(int argc, const char **argv, const char *prefix)
  87 {
  88         int fd, i;
  89         struct pack_refs_cb_data cbdata;
  90
  91         memset(&cbdata, 0, sizeof(cbdata));
  92
  93         for (i = 1; i < argc; i++) {
  94                 const char *arg = argv[i];
  95                 if (!strcmp(arg, "--prune")) {
  96                         cbdata.prune = 1;
  97                         continue;
  98                 }
  99                 if (!strcmp(arg, "--all")) {
 100                         cbdata.all = 1;
 101                         continue;
 102                 }
 103                 /* perhaps other parameters later... */
 104                 break;
 105         }
 106         if (i != argc)
 107                 usage(builtin_pack_refs_usage);
 108
 109         fd = hold_lock_file_for_update(&packed, git_path("packed-refs"), 1);
 110         cbdata.refs_file = fdopen(fd, "w");
 111         if (!cbdata.refs_file)
 112                 die("unable to create ref-pack file structure (%s)",
 113                     strerror(errno));
 114
 115         /* perhaps other traits later as well */
 116         fprintf(cbdata.refs_file, "# pack-refs with: peeled \n");
 117
 118         for_each_ref(handle_one_ref, &cbdata);
 119         fflush(cbdata.refs_file);
 120         fsync(fd);
 121         fclose(cbdata.refs_file);
 122         if (commit_lock_file(&packed) < 0)
 123                 die("unable to overwrite old ref-pack file (%s)", strerror(errno));
 124         if (cbdata.prune)
 125                 prune_refs(cbdata.ref_to_prune);
 126         return 0;
 127 }