Andrew's git - gitweb.git/blob

   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/*
  64 * Remove empty parents, but spare refs/ and immediate subdirs.
  65 * Note: munges *name.
  66 */
  67static void try_remove_empty_parents(char *name)
  68{
  69        char *p, *q;
  70        int i;
  71        p = name;
  72        for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */
  73                while (*p && *p != '/')
  74                        p++;
  75                /* tolerate duplicate slashes; see check_ref_format() */
  76                while (*p == '/')
  77                        p++;
  78        }
  79        for (q = p; *q; q++)
  80                ;
  81        while (1) {
  82                while (q > p && *q != '/')
  83                        q--;
  84                while (q > p && *(q-1) == '/')
  85                        q--;
  86                if (q == p)
  87                        break;
  88                *q = '\0';
  89                if (rmdir(git_path("%s", name)))
  90                        break;
  91        }
  92}
  93
  94/* make sure nobody touched the ref, and unlink */
  95static void prune_ref(struct ref_to_prune *r)
  96{
  97        struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
  98
  99        if (lock) {
 100                unlink_or_warn(git_path("%s", r->name));
 101                unlock_ref(lock);
 102                try_remove_empty_parents(r->name);
 103        }
 104}
 105
 106static void prune_refs(struct ref_to_prune *r)
 107{
 108        while (r) {
 109                prune_ref(r);
 110                r = r->next;
 111        }
 112}
 113
 114static struct lock_file packed;
 115
 116int pack_refs(unsigned int flags)
 117{
 118        int fd;
 119        struct pack_refs_cb_data cbdata;
 120
 121        memset(&cbdata, 0, sizeof(cbdata));
 122        cbdata.flags = flags;
 123
 124        fd = hold_lock_file_for_update(&packed, git_path("packed-refs"),
 125                                       LOCK_DIE_ON_ERROR);
 126        cbdata.refs_file = fdopen(fd, "w");
 127        if (!cbdata.refs_file)
 128                die_errno("unable to create ref-pack file structure");
 129
 130        /* perhaps other traits later as well */
 131        fprintf(cbdata.refs_file, "# pack-refs with: peeled \n");
 132
 133        for_each_ref(handle_one_ref, &cbdata);
 134        if (ferror(cbdata.refs_file))
 135                die("failed to write ref-pack file");
 136        if (fflush(cbdata.refs_file) || fsync(fd) || fclose(cbdata.refs_file))
 137                die_errno("failed to write ref-pack file");
 138        /*
 139         * Since the lock file was fdopen()'ed and then fclose()'ed above,
 140         * assign -1 to the lock file descriptor so that commit_lock_file()
 141         * won't try to close() it.
 142         */
 143        packed.fd = -1;
 144        if (commit_lock_file(&packed) < 0)
 145                die_errno("unable to overwrite old ref-pack file");
 146        if (cbdata.flags & PACK_REFS_PRUNE)
 147                prune_refs(cbdata.ref_to_prune);
 148        return 0;
 149}