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 #include "parse-options.h"
   7
   8 struct ref_to_prune {
   9         struct ref_to_prune *next;
  10         unsigned char sha1[20];
  11         char name[FLEX_ARRAY];
  12 };
  13
  14 #define PACK_REFS_PRUNE 0x0001
  15 #define PACK_REFS_ALL   0x0002
  16
  17 struct pack_refs_cb_data {
  18         unsigned int flags;
  19         struct ref_to_prune *ref_to_prune;
  20         FILE *refs_file;
  21 };
  22
  23 static int do_not_prune(int flags)
  24 {
  25         /* If it is already packed or if it is a symref,
  26          * do not prune it.
  27          */
  28         return (flags & (REF_ISSYMREF|REF_ISPACKED));
  29 }
  30
  31 static int handle_one_ref(const char *path, const unsigned char *sha1,
  32                           int flags, void *cb_data)
  33 {
  34         struct pack_refs_cb_data *cb = cb_data;
  35         int is_tag_ref;
  36
  37         /* Do not pack the symbolic refs */
  38         if ((flags & REF_ISSYMREF))
  39                 return 0;
  40         is_tag_ref = !prefixcmp(path, "refs/tags/");
  41
  42         /* ALWAYS pack refs that were already packed or are tags */
  43         if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref && !(flags & REF_ISPACKED))
  44                 return 0;
  45
  46         fprintf(cb->refs_file, "%s %s\n", sha1_to_hex(sha1), path);
  47         if (is_tag_ref) {
  48                 struct object *o = parse_object(sha1);
  49                 if (o->type == OBJ_TAG) {
  50                         o = deref_tag(o, path, 0);
  51                         if (o)
  52                                 fprintf(cb->refs_file, "^%s\n",
  53                                         sha1_to_hex(o->sha1));
  54                 }
  55         }
  56
  57         if ((cb->flags & PACK_REFS_PRUNE) && !do_not_prune(flags)) {
  58                 int namelen = strlen(path) + 1;
  59                 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
  60                 hashcpy(n->sha1, sha1);
  61                 strcpy(n->name, path);
  62                 n->next = cb->ref_to_prune;
  63                 cb->ref_to_prune = n;
  64         }
  65         return 0;
  66 }
  67
  68 /* make sure nobody touched the ref, and unlink */
  69 static void prune_ref(struct ref_to_prune *r)
  70 {
  71         struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
  72
  73         if (lock) {
  74                 unlink(git_path("%s", r->name));
  75                 unlock_ref(lock);
  76         }
  77 }
  78
  79 static void prune_refs(struct ref_to_prune *r)
  80 {
  81         while (r) {
  82                 prune_ref(r);
  83                 r = r->next;
  84         }
  85 }
  86
  87 static struct lock_file packed;
  88
  89 static int pack_refs(unsigned int flags)
  90 {
  91         int fd;
  92         struct pack_refs_cb_data cbdata;
  93
  94         memset(&cbdata, 0, sizeof(cbdata));
  95         cbdata.flags = flags;
  96
  97         fd = hold_lock_file_for_update(&packed, git_path("packed-refs"), 1);
  98         cbdata.refs_file = fdopen(fd, "w");
  99         if (!cbdata.refs_file)
 100                 die("unable to create ref-pack file structure (%s)",
 101                     strerror(errno));
 102
 103         /* perhaps other traits later as well */
 104         fprintf(cbdata.refs_file, "# pack-refs with: peeled \n");
 105
 106         for_each_ref(handle_one_ref, &cbdata);
 107         if (ferror(cbdata.refs_file))
 108                 die("failed to write ref-pack file");
 109         if (fflush(cbdata.refs_file) || fsync(fd) || fclose(cbdata.refs_file))
 110                 die("failed to write ref-pack file (%s)", strerror(errno));
 111         /*
 112          * Since the lock file was fdopen()'ed and then fclose()'ed above,
 113          * assign -1 to the lock file descriptor so that commit_lock_file()
 114          * won't try to close() it.
 115          */
 116         packed.fd = -1;
 117         if (commit_lock_file(&packed) < 0)
 118                 die("unable to overwrite old ref-pack file (%s)", strerror(errno));
 119         if (cbdata.flags & PACK_REFS_PRUNE)
 120                 prune_refs(cbdata.ref_to_prune);
 121         return 0;
 122 }
 123
 124 static char const * const pack_refs_usage[] = {
 125         "git-pack-refs [options]",
 126         NULL
 127 };
 128
 129 int cmd_pack_refs(int argc, const char **argv, const char *prefix)
 130 {
 131         unsigned int flags = PACK_REFS_PRUNE;
 132         struct option opts[] = {
 133                 OPT_BIT(0, "all",   &flags, "pack everything", PACK_REFS_ALL),
 134                 OPT_BIT(0, "prune", &flags, "prune loose refs (default)", PACK_REFS_PRUNE),
 135                 OPT_END(),
 136         };
 137         if (parse_options(argc, argv, opts, pack_refs_usage, 0))
 138                 usage_with_options(pack_refs_usage, opts);
 139         return pack_refs(flags);
 140 }