push: introduce new push.default mode "simple"
[gitweb.git] / builtin / merge.c
index 7349396d5b44f6ee894e0f0f50e2b66bb31203be..08e01e8a60d7d7f9c60e9e7a3a2f8b4d66c12ce3 100644 (file)
@@ -27,6 +27,7 @@
 #include "resolve-undo.h"
 #include "remote.h"
 #include "fmt-merge-msg.h"
+#include "gpg-interface.h"
 
 #define DEFAULT_TWOHEAD (1<<0)
 #define DEFAULT_OCTOPUS (1<<1)
@@ -47,9 +48,10 @@ static const char * const builtin_merge_usage[] = {
 
 static int show_diffstat = 1, shortlog_len = -1, squash;
 static int option_commit = 1, allow_fast_forward = 1;
-static int fast_forward_only, option_edit;
+static int fast_forward_only, option_edit = -1;
 static int allow_trivial = 1, have_message;
-static struct strbuf merge_msg;
+static int overwrite_ignore = 1;
+static struct strbuf merge_msg = STRBUF_INIT;
 static struct commit_list *remoteheads;
 static struct strategy **use_strategies;
 static size_t use_strategies_nr, use_strategies_alloc;
@@ -63,6 +65,7 @@ static int allow_rerere_auto;
 static int abort_current_merge;
 static int show_progress = -1;
 static int default_to_upstream;
+static const char *sign_commit;
 
 static struct strategy all_strategy[] = {
        { "recursive",  DEFAULT_TWOHEAD | NO_TRIVIAL },
@@ -190,7 +193,7 @@ static struct option builtin_merge_options[] = {
                "create a single commit instead of doing a merge"),
        OPT_BOOLEAN(0, "commit", &option_commit,
                "perform a commit if the merge succeeds (default)"),
-       OPT_BOOLEAN('e', "edit", &option_edit,
+       OPT_BOOL('e', "edit", &option_edit,
                "edit message before committing"),
        OPT_BOOLEAN(0, "ff", &allow_fast_forward,
                "allow fast-forward (default)"),
@@ -208,6 +211,9 @@ static struct option builtin_merge_options[] = {
        OPT_BOOLEAN(0, "abort", &abort_current_merge,
                "abort the current in-progress merge"),
        OPT_SET_INT(0, "progress", &show_progress, "force progress reporting", 1),
+       { OPTION_STRING, 'S', "gpg-sign", &sign_commit, "key id",
+         "GPG sign commit", PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
+       OPT_BOOLEAN(0, "overwrite-ignore", &overwrite_ignore, "update ignored files (default)"),
        OPT_END()
 };
 
@@ -393,6 +399,8 @@ static void finish(struct commit *head_commit,
        if (new_head && show_diffstat) {
                struct diff_options opts;
                diff_setup(&opts);
+               opts.stat_width = -1; /* use full terminal width */
+               opts.stat_graph_width = -1; /* respect statGraphWidth config */
                opts.output_format |=
                        DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
                opts.detect_rename = DIFF_DETECT_RENAME;
@@ -413,7 +421,7 @@ static void finish(struct commit *head_commit,
 static void merge_name(const char *remote, struct strbuf *msg)
 {
        struct commit *remote_head;
-       unsigned char branch_head[20], buf_sha[20];
+       unsigned char branch_head[20];
        struct strbuf buf = STRBUF_INIT;
        struct strbuf bname = STRBUF_INIT;
        const char *ptr;
@@ -477,7 +485,7 @@ static void merge_name(const char *remote, struct strbuf *msg)
                strbuf_addstr(&truname, "refs/heads/");
                strbuf_addstr(&truname, remote);
                strbuf_setlen(&truname, truname.len - len);
-               if (resolve_ref(truname.buf, buf_sha, 1, NULL)) {
+               if (ref_exists(truname.buf)) {
                        strbuf_addf(msg,
                                    "%s\t\tbranch '%s'%s of .\n",
                                    sha1_to_hex(remote_head->object.sha1),
@@ -569,7 +577,11 @@ static int git_merge_config(const char *k, const char *v, void *cb)
                default_to_upstream = git_config_bool(k, v);
                return 0;
        }
+
        status = fmt_merge_msg_config(k, v, cb);
+       if (status)
+               return status;
+       status = git_gpg_config(k, v, NULL);
        if (status)
                return status;
        return git_diff_ui_config(k, v, cb);
@@ -766,10 +778,12 @@ int checkout_fast_forward(const unsigned char *head, const unsigned char *remote
        memset(&trees, 0, sizeof(trees));
        memset(&opts, 0, sizeof(opts));
        memset(&t, 0, sizeof(t));
-       memset(&dir, 0, sizeof(dir));
-       dir.flags |= DIR_SHOW_IGNORED;
-       setup_standard_excludes(&dir);
-       opts.dir = &dir;
+       if (overwrite_ignore) {
+               memset(&dir, 0, sizeof(dir));
+               dir.flags |= DIR_SHOW_IGNORED;
+               setup_standard_excludes(&dir);
+               opts.dir = &dir;
+       }
 
        opts.head_idx = 1;
        opts.src_index = &the_index;
@@ -873,20 +887,30 @@ static void abort_commit(const char *err_msg)
        exit(1);
 }
 
+static const char merge_editor_comment[] =
+N_("Please enter a commit message to explain why this merge is necessary,\n"
+   "especially if it merges an updated upstream into a topic branch.\n"
+   "\n"
+   "Lines starting with '#' will be ignored, and an empty message aborts\n"
+   "the commit.\n");
+
 static void prepare_to_commit(void)
 {
        struct strbuf msg = STRBUF_INIT;
+       const char *comment = _(merge_editor_comment);
        strbuf_addbuf(&msg, &merge_msg);
        strbuf_addch(&msg, '\n');
+       if (0 < option_edit)
+               strbuf_add_lines(&msg, "# ", comment, strlen(comment));
        write_merge_msg(&msg);
        run_hook(get_index_file(), "prepare-commit-msg",
                 git_path("MERGE_MSG"), "merge", NULL, NULL);
-       if (option_edit) {
+       if (0 < option_edit) {
                if (launch_editor(git_path("MERGE_MSG"), NULL, NULL))
                        abort_commit(NULL);
        }
        read_merge_msg(&msg);
-       stripspace(&msg, option_edit);
+       stripspace(&msg, 0 < option_edit);
        if (!msg.len)
                abort_commit(_("Empty commit message."));
        strbuf_release(&merge_msg);
@@ -906,7 +930,9 @@ static int merge_trivial(struct commit *head)
        parent->next->item = remoteheads->item;
        parent->next->next = NULL;
        prepare_to_commit();
-       commit_tree(merge_msg.buf, result_tree, parent, result_commit, NULL);
+       if (commit_tree(&merge_msg, result_tree, parent, result_commit, NULL,
+                       sign_commit))
+               die(_("failed to write commit object"));
        finish(head, result_commit, "In-index merge");
        drop_save();
        return 0;
@@ -937,7 +963,9 @@ static int finish_automerge(struct commit *head,
        strbuf_addch(&merge_msg, '\n');
        prepare_to_commit();
        free_commit_list(remoteheads);
-       commit_tree(merge_msg.buf, result_tree, parents, result_commit, NULL);
+       if (commit_tree(&merge_msg, result_tree, parents, result_commit,
+                       NULL, sign_commit))
+               die(_("failed to write commit object"));
        strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
        finish(head, result_commit, buf.buf);
        strbuf_release(&buf);
@@ -1083,6 +1111,33 @@ static void write_merge_state(void)
        close(fd);
 }
 
+static int default_edit_option(void)
+{
+       static const char name[] = "GIT_MERGE_AUTOEDIT";
+       const char *e = getenv(name);
+       struct stat st_stdin, st_stdout;
+
+       if (have_message)
+               /* an explicit -m msg without --[no-]edit */
+               return 0;
+
+       if (e) {
+               int v = git_config_maybe_bool(name, e);
+               if (v < 0)
+                       die("Bad value '%s' in environment '%s'", e, name);
+               return v;
+       }
+
+       /* Use editor if stdin and stdout are the same and is a tty */
+       return (!fstat(0, &st_stdin) &&
+               !fstat(1, &st_stdout) &&
+               isatty(0) && isatty(1) &&
+               st_stdin.st_dev == st_stdout.st_dev &&
+               st_stdin.st_ino == st_stdout.st_ino &&
+               st_stdin.st_mode == st_stdout.st_mode);
+}
+
+
 int cmd_merge(int argc, const char **argv, const char *prefix)
 {
        unsigned char result_tree[20];
@@ -1091,11 +1146,12 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
        struct commit *head_commit;
        struct strbuf buf = STRBUF_INIT;
        const char *head_arg;
-       int flag, i;
+       int flag, i, ret = 0;
        int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
        struct commit_list *common = NULL;
        const char *best_strategy = NULL, *wt_strategy = NULL;
        struct commit_list **remotes = &remoteheads;
+       void *branch_to_free;
 
        if (argc == 2 && !strcmp(argv[1], "-h"))
                usage_with_options(builtin_merge_usage, builtin_merge_options);
@@ -1104,7 +1160,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
         * Check if we are _not_ on a detached HEAD, i.e. if there is a
         * current branch.
         */
-       branch = resolve_ref("HEAD", head_sha1, 0, &flag);
+       branch = branch_to_free = resolve_refdup("HEAD", head_sha1, 0, &flag);
        if (branch && !prefixcmp(branch, "refs/heads/"))
                branch += 11;
        if (!branch || is_null_sha1(head_sha1))
@@ -1132,7 +1188,8 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                        die(_("There is no merge to abort (MERGE_HEAD missing)."));
 
                /* Invoke 'git reset --merge' */
-               return cmd_reset(nargc, nargv, prefix);
+               ret = cmd_reset(nargc, nargv, prefix);
+               goto done;
        }
 
        if (read_cache_unmerged())
@@ -1219,7 +1276,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                read_empty(remote_head->object.sha1, 0);
                update_ref("initial pull", "HEAD", remote_head->object.sha1,
                           NULL, 0, DIE_ON_ERR);
-               return 0;
+               goto done;
        } else {
                struct strbuf merge_names = STRBUF_INIT;
 
@@ -1265,14 +1322,16 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                            sha1_to_hex(commit->object.sha1));
                setenv(buf.buf, argv[i], 1);
                strbuf_reset(&buf);
-               if (merge_remote_util(commit) &&
+               if (!fast_forward_only &&
+                   merge_remote_util(commit) &&
                    merge_remote_util(commit)->obj &&
-                   merge_remote_util(commit)->obj->type == OBJ_TAG) {
-                       option_edit = 1;
+                   merge_remote_util(commit)->obj->type == OBJ_TAG)
                        allow_fast_forward = 0;
-               }
        }
 
+       if (option_edit < 0)
+               option_edit = default_edit_option();
+
        if (!use_strategies) {
                if (!remoteheads->next)
                        add_strategies(pull_twohead, DEFAULT_TWOHEAD);
@@ -1308,7 +1367,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                 * but first the most common case of merging one remote.
                 */
                finish_up_to_date("Already up-to-date.");
-               return 0;
+               goto done;
        } else if (allow_fast_forward && !remoteheads->next &&
                        !common->next &&
                        !hashcmp(common->item->object.sha1, head_commit->object.sha1)) {
@@ -1329,16 +1388,20 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                        strbuf_addstr(&msg,
                                " (no commit created; -m option ignored)");
                commit = remoteheads->item;
-               if (!commit)
-                       return 1;
+               if (!commit) {
+                       ret = 1;
+                       goto done;
+               }
 
                if (checkout_fast_forward(head_commit->object.sha1,
-                                         commit->object.sha1))
-                       return 1;
+                                         commit->object.sha1)) {
+                       ret = 1;
+                       goto done;
+               }
 
                finish(head_commit, commit->object.sha1, msg.buf);
                drop_save();
-               return 0;
+               goto done;
        } else if (!remoteheads->next && common->next)
                ;
                /*
@@ -1356,8 +1419,11 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                        git_committer_info(IDENT_ERROR_ON_NO_NAME);
                        printf(_("Trying really trivial in-index merge...\n"));
                        if (!read_tree_trivial(common->item->object.sha1,
-                                       head_commit->object.sha1, remoteheads->item->object.sha1))
-                               return merge_trivial(head_commit);
+                                              head_commit->object.sha1,
+                                              remoteheads->item->object.sha1)) {
+                               ret = merge_trivial(head_commit);
+                               goto done;
+                       }
                        printf(_("Nope.\n"));
                }
        } else {
@@ -1385,7 +1451,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                }
                if (up_to_date) {
                        finish_up_to_date("Already up-to-date. Yeeah!");
-                       return 0;
+                       goto done;
                }
        }
 
@@ -1467,9 +1533,11 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
         * If we have a resulting tree, that means the strategy module
         * auto resolved the merge cleanly.
         */
-       if (automerge_was_ok)
-               return finish_automerge(head_commit, common, result_tree,
-                                       wt_strategy);
+       if (automerge_was_ok) {
+               ret = finish_automerge(head_commit, common, result_tree,
+                                      wt_strategy);
+               goto done;
+       }
 
        /*
         * Pick the result from the best strategy and have the user fix
@@ -1483,7 +1551,8 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                else
                        fprintf(stderr, _("Merge with strategy %s failed.\n"),
                                use_strategies[0]->name);
-               return 2;
+               ret = 2;
+               goto done;
        } else if (best_strategy == wt_strategy)
                ; /* We already have its result in the working tree. */
        else {
@@ -1499,10 +1568,13 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
        else
                write_merge_state();
 
-       if (merge_was_ok) {
+       if (merge_was_ok)
                fprintf(stderr, _("Automatic merge went well; "
                        "stopped before committing as requested\n"));
-               return 0;
-       } else
-               return suggest_conflicts(option_renormalize);
+       else
+               ret = suggest_conflicts(option_renormalize);
+
+done:
+       free(branch_to_free);
+       return ret;
 }