src/fetch.c

   1 /*
   2  * Copyright (C) 2009-2012 the libgit2 contributors
   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 "git2/oid.h"
   9 #include "git2/refs.h"
  10 #include "git2/revwalk.h"
  11 #include "git2/transport.h"
  12
  13 #include "common.h"
  14 #include "remote.h"
  15 #include "refspec.h"
  16 #include "pack.h"
  17 #include "fetch.h"
  18 #include "netops.h"
  19
  20 struct filter_payload {
  21         git_remote *remote;
  22         const git_refspec *spec, *tagspec;
  23         git_odb *odb;
  24         int found_head;
  25 };
  26
  27 static int filter_ref__cb(git_remote_head *head, void *payload)
  28 {
  29         struct filter_payload *p = payload;
  30         int match = 0;
  31
  32         if (!git_reference_is_valid_name(head->name))
  33                 return 0;
  34
  35         if (!p->found_head && strcmp(head->name, GIT_HEAD_FILE) == 0)
  36                 p->found_head = 1;
  37         else if (git_refspec_src_matches(p->spec, head->name))
  38                         match = 1;
  39         else if (p->remote->download_tags == GIT_REMOTE_DOWNLOAD_TAGS_ALL &&
  40                  git_refspec_src_matches(p->tagspec, head->name))
  41                         match = 1;
  42
  43         if (!match)
  44                 return 0;
  45
  46         /* If we have the object, mark it so we don't ask for it */
  47         if (git_odb_exists(p->odb, &head->oid))
  48                 head->local = 1;
  49         else
  50                 p->remote->need_pack = 1;
  51
  52         return git_vector_insert(&p->remote->refs, head);
  53 }
  54
  55 static int filter_wants(git_remote *remote)
  56 {
  57         struct filter_payload p;
  58         git_refspec tagspec;
  59         int error = -1;
  60
  61         git_vector_clear(&remote->refs);
  62         if (git_refspec__parse(&tagspec, GIT_REFSPEC_TAGS, true) < 0)
  63                 return error;
  64
  65         /*
  66          * The fetch refspec can be NULL, and what this means is that the
  67          * user didn't specify one. This is fine, as it means that we're
  68          * not interested in any particular branch but just the remote's
  69          * HEAD, which will be stored in FETCH_HEAD after the fetch.
  70          */
  71         p.spec = git_remote_fetchspec(remote);
  72         p.tagspec = &tagspec;
  73         p.found_head = 0;
  74         p.remote = remote;
  75
  76         if (git_repository_odb__weakptr(&p.odb, remote->repo) < 0)
  77                 goto cleanup;
  78
  79         error = git_remote_ls(remote, filter_ref__cb, &p);
  80
  81 cleanup:
  82         git_refspec__free(&tagspec);
  83
  84         return error;
  85 }
  86
  87 /*
  88  * In this first version, we push all our refs in and start sending
  89  * them out. When we get an ACK we hide that commit and continue
  90  * traversing until we're done
  91  */
  92 int git_fetch_negotiate(git_remote *remote)
  93 {
  94         git_transport *t = remote->transport;
  95
  96         if (filter_wants(remote) < 0) {
  97                 giterr_set(GITERR_NET, "Failed to filter the reference list for wants");
  98                 return -1;
  99         }
 100
 101         /* Don't try to negotiate when we don't want anything */
 102         if (remote->refs.length == 0 || !remote->need_pack)
 103                 return 0;
 104
 105         /*
 106          * Now we have everything set up so we can start tell the
 107          * server what we want and what we have.
 108          */
 109         return t->negotiate_fetch(t,
 110                 remote->repo,
 111                 (const git_remote_head * const *)remote->refs.contents,
 112                 remote->refs.length);
 113 }
 114
 115 int git_fetch_download_pack(
 116         git_remote *remote,
 117         git_transfer_progress_callback progress_cb,
 118         void *progress_payload)
 119 {
 120         git_transport *t = remote->transport;
 121
 122         if(!remote->need_pack)
 123                 return 0;
 124
 125         return t->download_pack(t, remote->repo, &remote->stats, progress_cb, progress_payload);
 126 }