src/libgit2/cherrypick.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 "common.h"
   9
  10 #include "repository.h"
  11 #include "filebuf.h"
  12 #include "merge.h"
  13 #include "vector.h"
  14 #include "index.h"
  15
  16 #include "git2/types.h"
  17 #include "git2/merge.h"
  18 #include "git2/cherrypick.h"
  19 #include "git2/commit.h"
  20 #include "git2/sys/commit.h"
  21
  22 #define GIT_CHERRYPICK_FILE_MODE                0666
  23
  24 static int write_cherrypick_head(
  25         git_repository *repo,
  26         const char *commit_oidstr)
  27 {
  28         git_filebuf file = GIT_FILEBUF_INIT;
  29         git_str file_path = GIT_STR_INIT;
  30         int error = 0;
  31
  32         if ((error = git_str_joinpath(&file_path, repo->gitdir, GIT_CHERRYPICK_HEAD_FILE)) >= 0 &&
  33                 (error = git_filebuf_open(&file, file_path.ptr, GIT_FILEBUF_CREATE_LEADING_DIRS, GIT_CHERRYPICK_FILE_MODE)) >= 0 &&
  34                 (error = git_filebuf_printf(&file, "%s\n", commit_oidstr)) >= 0)
  35                 error = git_filebuf_commit(&file);
  36
  37         if (error < 0)
  38                 git_filebuf_cleanup(&file);
  39
  40         git_str_dispose(&file_path);
  41
  42         return error;
  43 }
  44
  45 static int write_merge_msg(
  46         git_repository *repo,
  47         const char *commit_msg)
  48 {
  49         git_filebuf file = GIT_FILEBUF_INIT;
  50         git_str file_path = GIT_STR_INIT;
  51         int error = 0;
  52
  53         if ((error = git_str_joinpath(&file_path, repo->gitdir, GIT_MERGE_MSG_FILE)) < 0 ||
  54                 (error = git_filebuf_open(&file, file_path.ptr, GIT_FILEBUF_CREATE_LEADING_DIRS, GIT_CHERRYPICK_FILE_MODE)) < 0 ||
  55                 (error = git_filebuf_printf(&file, "%s", commit_msg)) < 0)
  56                 goto cleanup;
  57
  58         error = git_filebuf_commit(&file);
  59
  60 cleanup:
  61         if (error < 0)
  62                 git_filebuf_cleanup(&file);
  63
  64         git_str_dispose(&file_path);
  65
  66         return error;
  67 }
  68
  69 static int cherrypick_normalize_opts(
  70         git_repository *repo,
  71         git_cherrypick_options *opts,
  72         const git_cherrypick_options *given,
  73         const char *their_label)
  74 {
  75         int error = 0;
  76         unsigned int default_checkout_strategy = GIT_CHECKOUT_SAFE |
  77                 GIT_CHECKOUT_ALLOW_CONFLICTS;
  78
  79         GIT_UNUSED(repo);
  80
  81         if (given != NULL)
  82                 memcpy(opts, given, sizeof(git_cherrypick_options));
  83         else {
  84                 git_cherrypick_options default_opts = GIT_CHERRYPICK_OPTIONS_INIT;
  85                 memcpy(opts, &default_opts, sizeof(git_cherrypick_options));
  86         }
  87
  88         if (!opts->checkout_opts.checkout_strategy)
  89                 opts->checkout_opts.checkout_strategy = default_checkout_strategy;
  90
  91         if (!opts->checkout_opts.our_label)
  92                 opts->checkout_opts.our_label = "HEAD";
  93
  94         if (!opts->checkout_opts.their_label)
  95                 opts->checkout_opts.their_label = their_label;
  96
  97         return error;
  98 }
  99
 100 static int cherrypick_state_cleanup(git_repository *repo)
 101 {
 102         const char *state_files[] = { GIT_CHERRYPICK_HEAD_FILE, GIT_MERGE_MSG_FILE };
 103
 104         return git_repository__cleanup_files(repo, state_files, ARRAY_SIZE(state_files));
 105 }
 106
 107 static int cherrypick_seterr(git_commit *commit, const char *fmt)
 108 {
 109         char commit_oidstr[GIT_OID_HEXSZ + 1];
 110
 111         git_error_set(GIT_ERROR_CHERRYPICK, fmt,
 112                 git_oid_tostr(commit_oidstr, GIT_OID_HEXSZ + 1, git_commit_id(commit)));
 113
 114         return -1;
 115 }
 116
 117 int git_cherrypick_commit(
 118         git_index **out,
 119         git_repository *repo,
 120         git_commit *cherrypick_commit,
 121         git_commit *our_commit,
 122         unsigned int mainline,
 123         const git_merge_options *merge_opts)
 124 {
 125         git_commit *parent_commit = NULL;
 126         git_tree *parent_tree = NULL, *our_tree = NULL, *cherrypick_tree = NULL;
 127         int parent = 0, error = 0;
 128
 129         GIT_ASSERT_ARG(out);
 130         GIT_ASSERT_ARG(repo);
 131         GIT_ASSERT_ARG(cherrypick_commit);
 132         GIT_ASSERT_ARG(our_commit);
 133
 134         if (git_commit_parentcount(cherrypick_commit) > 1) {
 135                 if (!mainline)
 136                         return cherrypick_seterr(cherrypick_commit,
 137                                 "mainline branch is not specified but %s is a merge commit");
 138
 139                 parent = mainline;
 140         } else {
 141                 if (mainline)
 142                         return cherrypick_seterr(cherrypick_commit,
 143                                 "mainline branch specified but %s is not a merge commit");
 144
 145                 parent = git_commit_parentcount(cherrypick_commit);
 146         }
 147
 148         if (parent &&
 149                 ((error = git_commit_parent(&parent_commit, cherrypick_commit, (parent - 1))) < 0 ||
 150                 (error = git_commit_tree(&parent_tree, parent_commit)) < 0))
 151                 goto done;
 152
 153         if ((error = git_commit_tree(&cherrypick_tree, cherrypick_commit)) < 0 ||
 154                 (error = git_commit_tree(&our_tree, our_commit)) < 0)
 155                 goto done;
 156
 157         error = git_merge_trees(out, repo, parent_tree, our_tree, cherrypick_tree, merge_opts);
 158
 159 done:
 160         git_tree_free(parent_tree);
 161         git_tree_free(our_tree);
 162         git_tree_free(cherrypick_tree);
 163         git_commit_free(parent_commit);
 164
 165         return error;
 166 }
 167
 168 int git_cherrypick(
 169         git_repository *repo,
 170         git_commit *commit,
 171         const git_cherrypick_options *given_opts)
 172 {
 173         git_cherrypick_options opts;
 174         git_reference *our_ref = NULL;
 175         git_commit *our_commit = NULL;
 176         char commit_oidstr[GIT_OID_HEXSZ + 1];
 177         const char *commit_msg, *commit_summary;
 178         git_str their_label = GIT_STR_INIT;
 179         git_index *index = NULL;
 180         git_indexwriter indexwriter = GIT_INDEXWRITER_INIT;
 181         int error = 0;
 182
 183         GIT_ASSERT_ARG(repo);
 184         GIT_ASSERT_ARG(commit);
 185
 186         GIT_ERROR_CHECK_VERSION(given_opts, GIT_CHERRYPICK_OPTIONS_VERSION, "git_cherrypick_options");
 187
 188         if ((error = git_repository__ensure_not_bare(repo, "cherry-pick")) < 0)
 189                 return error;
 190
 191         if ((commit_msg = git_commit_message(commit)) == NULL ||
 192                 (commit_summary = git_commit_summary(commit)) == NULL) {
 193                 error = -1;
 194                 goto on_error;
 195         }
 196
 197         git_oid_nfmt(commit_oidstr, sizeof(commit_oidstr), git_commit_id(commit));
 198
 199         if ((error = write_merge_msg(repo, commit_msg)) < 0 ||
 200                 (error = git_str_printf(&their_label, "%.7s... %s", commit_oidstr, commit_summary)) < 0 ||
 201                 (error = cherrypick_normalize_opts(repo, &opts, given_opts, git_str_cstr(&their_label))) < 0 ||
 202                 (error = git_indexwriter_init_for_operation(&indexwriter, repo, &opts.checkout_opts.checkout_strategy)) < 0 ||
 203                 (error = write_cherrypick_head(repo, commit_oidstr)) < 0 ||
 204                 (error = git_repository_head(&our_ref, repo)) < 0 ||
 205                 (error = git_reference_peel((git_object **)&our_commit, our_ref, GIT_OBJECT_COMMIT)) < 0 ||
 206                 (error = git_cherrypick_commit(&index, repo, commit, our_commit, opts.mainline, &opts.merge_opts)) < 0 ||
 207                 (error = git_merge__check_result(repo, index)) < 0 ||
 208                 (error = git_merge__append_conflicts_to_merge_msg(repo, index)) < 0 ||
 209                 (error = git_checkout_index(repo, index, &opts.checkout_opts)) < 0 ||
 210                 (error = git_indexwriter_commit(&indexwriter)) < 0)
 211                 goto on_error;
 212
 213         goto done;
 214
 215 on_error:
 216         cherrypick_state_cleanup(repo);
 217
 218 done:
 219         git_indexwriter_cleanup(&indexwriter);
 220         git_index_free(index);
 221         git_commit_free(our_commit);
 222         git_reference_free(our_ref);
 223         git_str_dispose(&their_label);
 224
 225         return error;
 226 }
 227
 228 int git_cherrypick_options_init(
 229         git_cherrypick_options *opts, unsigned int version)
 230 {
 231         GIT_INIT_STRUCTURE_FROM_TEMPLATE(
 232                 opts, version, git_cherrypick_options, GIT_CHERRYPICK_OPTIONS_INIT);
 233         return 0;
 234 }
 235
 236 #ifndef GIT_DEPRECATE_HARD
 237 int git_cherrypick_init_options(
 238         git_cherrypick_options *opts, unsigned int version)
 239 {
 240         return git_cherrypick_options_init(opts, version);
 241 }
 242 #endif