builtin-pack-refs.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "refs.h"
   4 #include "object.h"
   5 #include "tag.h"
   6
   7 static const char builtin_pack_refs_usage[] =
   8 "git-pack-refs [--all] [--prune | --no-prune]";
   9
  10 struct ref_to_prune {
  11         struct ref_to_prune *next;
  12         unsigned char sha1[20];
  13         char name[FLEX_ARRAY];
  14 };
  15
  16 #define PACK_REFS_PRUNE 0x0001
  17 #define PACK_REFS_ALL   0x0002
  18
  19 struct pack_refs_cb_data {
  20         unsigned int flags;
  21         struct ref_to_prune *ref_to_prune;
  22         FILE *refs_file;
  23 };
  24
  25 static int do_not_prune(int flags)
  26 {
  27         /* If it is already packed or if it is a symref,
  28          * do not prune it.
  29          */
  30         return (flags & (REF_ISSYMREF|REF_ISPACKED));
  31 }
  32
  33 static int handle_one_ref(const char *path, const unsigned char *sha1,
  34                           int flags, void *cb_data)
  35 {
  36         struct pack_refs_cb_data *cb = cb_data;
  37         int is_tag_ref;
  38
  39         /* Do not pack the symbolic refs */
  40         if ((flags & REF_ISSYMREF))
  41                 return 0;
  42         is_tag_ref = !prefixcmp(path, "refs/tags/");
  43
  44         /* ALWAYS pack refs that were already packed or are tags */
  45         if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref && !(flags & REF_ISPACKED))
  46                 return 0;
  47
  48         fprintf(cb->refs_file, "%s %s\n", sha1_to_hex(sha1), path);
  49         if (is_tag_ref) {
  50                 struct object *o = parse_object(sha1);
  51                 if (o->type == OBJ_TAG) {
  52                         o = deref_tag(o, path, 0);
  53                         if (o)
  54                                 fprintf(cb->refs_file, "^%s\n",
  55                                         sha1_to_hex(o->sha1));
  56                 }
  57         }
  58
  59         if ((cb->flags & PACK_REFS_PRUNE) && !do_not_prune(flags)) {
  60                 int namelen = strlen(path) + 1;
  61                 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
  62                 hashcpy(n->sha1, sha1);
  63                 strcpy(n->name, path);
  64                 n->next = cb->ref_to_prune;
  65                 cb->ref_to_prune = n;
  66         }
  67         return 0;
  68 }
  69
  70 /* make sure nobody touched the ref, and unlink */
  71 static void prune_ref(struct ref_to_prune *r)
  72 {
  73         struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
  74
  75         if (lock) {
  76                 unlink(git_path("%s", r->name));
  77                 unlock_ref(lock);
  78         }
  79 }
  80
  81 static void prune_refs(struct ref_to_prune *r)
  82 {
  83         while (r) {
  84                 prune_ref(r);
  85                 r = r->next;
  86         }
  87 }
  88
  89 static struct lock_file packed;
  90
  91 static int pack_refs(unsigned int flags)
  92 {
  93         int fd;
  94         struct pack_refs_cb_data cbdata;
  95
  96         memset(&cbdata, 0, sizeof(cbdata));
  97         cbdata.flags = flags;
  98
  99         fd = hold_lock_file_for_update(&packed, git_path("packed-refs"), 1);
 100         cbdata.refs_file = fdopen(fd, "w");
 101         if (!cbdata.refs_file)
 102                 die("unable to create ref-pack file structure (%s)",
 103                     strerror(errno));
 104
 105         /* perhaps other traits later as well */
 106         fprintf(cbdata.refs_file, "# pack-refs with: peeled \n");
 107
 108         for_each_ref(handle_one_ref, &cbdata);
 109         if (ferror(cbdata.refs_file))
 110                 die("failed to write ref-pack file");
 111         if (fflush(cbdata.refs_file) || fsync(fd) || fclose(cbdata.refs_file))
 112                 die("failed to write ref-pack file (%s)", strerror(errno));
 113         if (commit_lock_file(&packed) < 0)
 114                 die("unable to overwrite old ref-pack file (%s)", strerror(errno));
 115         if (cbdata.flags & PACK_REFS_PRUNE)
 116                 prune_refs(cbdata.ref_to_prune);
 117         return 0;
 118 }
 119
 120 int cmd_pack_refs(int argc, const char **argv, const char *prefix)
 121 {
 122         int i;
 123         unsigned int flags;
 124
 125         flags = PACK_REFS_PRUNE;
 126         for (i = 1; i < argc; i++) {
 127                 const char *arg = argv[i];
 128                 if (!strcmp(arg, "--prune")) {
 129                         flags |= PACK_REFS_PRUNE; /* now the default */
 130                         continue;
 131                 }
 132                 if (!strcmp(arg, "--no-prune")) {
 133                         flags &= ~PACK_REFS_PRUNE;
 134                         continue;
 135                 }
 136                 if (!strcmp(arg, "--all")) {
 137                         flags |= PACK_REFS_ALL;
 138                         continue;
 139                 }
 140                 /* perhaps other parameters later... */
 141                 break;
 142         }
 143         if (i != argc)
 144                 usage(builtin_pack_refs_usage);
 145
 146         return pack_refs(flags);
 147 }