src/fetch.c

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7
   8 #include "fetch.h"
   9
  10 #include "git2/oid.h"
  11 #include "git2/refs.h"
  12 #include "git2/revwalk.h"
  13 #include "git2/transport.h"
  14
  15 #include "remote.h"
  16 #include "refspec.h"
  17 #include "pack.h"
  18 #include "netops.h"
  19 #include "repository.h"
  20 #include "refs.h"
  21
  22 static int maybe_want(git_remote *remote, git_remote_head *head, git_odb *odb, git_refspec *tagspec, git_remote_autotag_option_t tagopt)
  23 {
  24         int match = 0;
  25
  26         if (!git_reference_is_valid_name(head->name))
  27                 return 0;
  28
  29         if (tagopt == GIT_REMOTE_DOWNLOAD_TAGS_ALL) {
  30                 /*
  31                  * If tagopt is --tags, always request tags
  32                  * in addition to the remote's refspecs
  33                  */
  34                 if (git_refspec_src_matches(tagspec, head->name))
  35                         match = 1;
  36         }
  37
  38         if (!match && git_remote__matching_refspec(remote, head->name))
  39                 match = 1;
  40
  41         if (!match)
  42                 return 0;
  43
  44         /* If we have the object, mark it so we don't ask for it */
  45         if (git_odb_exists(odb, &head->oid)) {
  46                 head->local = 1;
  47         }
  48         else
  49                 remote->need_pack = 1;
  50
  51         return git_vector_insert(&remote->refs, head);
  52 }
  53
  54 static int filter_wants(git_remote *remote, const git_fetch_options *opts)
  55 {
  56         git_remote_head **heads;
  57         git_refspec tagspec, head;
  58         int error = 0;
  59         git_odb *odb;
  60         size_t i, heads_len;
  61         git_remote_autotag_option_t tagopt = remote->download_tags;
  62
  63         if (opts && opts->download_tags != GIT_REMOTE_DOWNLOAD_TAGS_UNSPECIFIED)
  64                 tagopt = opts->download_tags;
  65
  66         git_vector_clear(&remote->refs);
  67         if ((error = git_refspec__parse(&tagspec, GIT_REFSPEC_TAGS, true)) < 0)
  68                 return error;
  69
  70         /*
  71          * The fetch refspec can be NULL, and what this means is that the
  72          * user didn't specify one. This is fine, as it means that we're
  73          * not interested in any particular branch but just the remote's
  74          * HEAD, which will be stored in FETCH_HEAD after the fetch.
  75          */
  76         if (remote->active_refspecs.length == 0) {
  77                 if ((error = git_refspec__parse(&head, "HEAD", true)) < 0)
  78                         goto cleanup;
  79
  80                 error = git_refspec__dwim_one(&remote->active_refspecs, &head, &remote->refs);
  81                 git_refspec__dispose(&head);
  82
  83                 if (error < 0)
  84                         goto cleanup;
  85         }
  86
  87         if (git_repository_odb__weakptr(&odb, remote->repo) < 0)
  88                 goto cleanup;
  89
  90         if (git_remote_ls((const git_remote_head ***)&heads, &heads_len, remote) < 0)
  91                 goto cleanup;
  92
  93         for (i = 0; i < heads_len; i++) {
  94                 if ((error = maybe_want(remote, heads[i], odb, &tagspec, tagopt)) < 0)
  95                         break;
  96         }
  97
  98 cleanup:
  99         git_refspec__dispose(&tagspec);
 100
 101         return error;
 102 }
 103
 104 /*
 105  * In this first version, we push all our refs in and start sending
 106  * them out. When we get an ACK we hide that commit and continue
 107  * traversing until we're done
 108  */
 109 int git_fetch_negotiate(git_remote *remote, const git_fetch_options *opts)
 110 {
 111         git_transport *t = remote->transport;
 112
 113         remote->need_pack = 0;
 114
 115         if (filter_wants(remote, opts) < 0) {
 116                 git_error_set(GIT_ERROR_NET, "failed to filter the reference list for wants");
 117                 return -1;
 118         }
 119
 120         /* Don't try to negotiate when we don't want anything */
 121         if (!remote->need_pack)
 122                 return 0;
 123
 124         /*
 125          * Now we have everything set up so we can start tell the
 126          * server what we want and what we have.
 127          */
 128         return t->negotiate_fetch(t,
 129                 remote->repo,
 130                 (const git_remote_head * const *)remote->refs.contents,
 131                 remote->refs.length);
 132 }
 133
 134 int git_fetch_download_pack(git_remote *remote, const git_remote_callbacks *callbacks)
 135 {
 136         git_transport *t = remote->transport;
 137         git_indexer_progress_cb progress = NULL;
 138         void *payload = NULL;
 139
 140         if (!remote->need_pack)
 141                 return 0;
 142
 143         if (callbacks) {
 144                 progress = callbacks->transfer_progress;
 145                 payload  = callbacks->payload;
 146         }
 147
 148         return t->download_pack(t, remote->repo, &remote->stats, progress, payload);
 149 }
 150
 151 int git_fetch_options_init(git_fetch_options *opts, unsigned int version)
 152 {
 153         GIT_INIT_STRUCTURE_FROM_TEMPLATE(
 154                 opts, version, git_fetch_options, GIT_FETCH_OPTIONS_INIT);
 155         return 0;
 156 }
 157
 158 #ifndef GIT_DEPRECATE_HARD
 159 int git_fetch_init_options(git_fetch_options *opts, unsigned int version)
 160 {
 161         return git_fetch_options_init(opts, version);
 162 }
 163 #endif