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