Merge branch 'mv/merge-in-c'

* mv/merge-in-c:
  reduce_heads(): protect from duplicate input
  reduce_heads(): thinkofix
  Add a new test for git-merge-resolve
  t6021: add a new test for git-merge-resolve
  Teach merge.log to "git-merge" again
  Build in merge
  Fix t7601-merge-pull-config.sh on AIX
  git-commit-tree: make it usable from other builtins
  Add new test case to ensure git-merge prepends the custom merge message
  Add new test case to ensure git-merge reduces octopus parents when possible
  Introduce reduce_heads()
  Introduce get_merge_bases_many()
  Add new test to ensure git-merge handles more than 25 refs.
  Introduce get_octopus_merge_bases() in commit.c
  git-fmt-merge-msg: make it usable from other builtins
  Move read_cache_unmerged() to read-cache.c
  Add new test to ensure git-merge handles pull.twohead and pull.octopus
  Move parse-options's skip_prefix() to git-compat-util.h
  Move commit_list_count() to commit.c
  Move split_cmdline() to alias.c

Conflicts:
	Makefile
	parse-options.c

Makefile

@@ -240,7 +240,6 @@ SCRIPT_SH += git-lost-found.sh
 SCRIPT_SH += git-merge-octopus.sh
 SCRIPT_SH += git-merge-one-file.sh
 SCRIPT_SH += git-merge-resolve.sh
-SCRIPT_SH += git-merge.sh
 SCRIPT_SH += git-mergetool.sh
 SCRIPT_SH += git-parse-remote.sh
 SCRIPT_SH += git-pull.sh
@@ -515,6 +514,7 @@ BUILTIN_OBJS += builtin-ls-remote.o
 BUILTIN_OBJS += builtin-ls-tree.o
 BUILTIN_OBJS += builtin-mailinfo.o
 BUILTIN_OBJS += builtin-mailsplit.o
+BUILTIN_OBJS += builtin-merge.o
 BUILTIN_OBJS += builtin-merge-base.o
 BUILTIN_OBJS += builtin-merge-file.o
 BUILTIN_OBJS += builtin-merge-ours.o

alias.c

@@ -21,3 +21,57 @@ char *alias_lookup(const char *alias)
 	git_config(alias_lookup_cb, NULL);
 	return alias_val;
 }
+
+int split_cmdline(char *cmdline, const char ***argv)
+{
+	int src, dst, count = 0, size = 16;
+	char quoted = 0;
+
+	*argv = xmalloc(sizeof(char*) * size);
+
+	/* split alias_string */
+	(*argv)[count++] = cmdline;
+	for (src = dst = 0; cmdline[src];) {
+		char c = cmdline[src];
+		if (!quoted && isspace(c)) {
+			cmdline[dst++] = 0;
+			while (cmdline[++src]
+					&& isspace(cmdline[src]))
+				; /* skip */
+			if (count >= size) {
+				size += 16;
+				*argv = xrealloc(*argv, sizeof(char*) * size);
+			}
+			(*argv)[count++] = cmdline + dst;
+		} else if (!quoted && (c == '\'' || c == '"')) {
+			quoted = c;
+			src++;
+		} else if (c == quoted) {
+			quoted = 0;
+			src++;
+		} else {
+			if (c == '\\' && quoted != '\'') {
+				src++;
+				c = cmdline[src];
+				if (!c) {
+					free(*argv);
+					*argv = NULL;
+					return error("cmdline ends with \\");
+				}
+			}
+			cmdline[dst++] = c;
+			src++;
+		}
+	}
+
+	cmdline[dst] = 0;
+
+	if (quoted) {
+		free(*argv);
+		*argv = NULL;
+		return error("unclosed quote");
+	}
+
+	return count;
+}
+

builtin-commit-tree.c

@@ -45,41 +45,19 @@ static const char commit_utf8_warn[] =
 "You may want to amend it after fixing the message, or set the config\n"
 "variable i18n.commitencoding to the encoding your project uses.\n";
 
-int cmd_commit_tree(int argc, const char **argv, const char *prefix)
+int commit_tree(const char *msg, unsigned char *tree,
+		struct commit_list *parents, unsigned char *ret)
 {
-	int i;
-	struct commit_list *parents = NULL;
-	unsigned char tree_sha1[20];
-	unsigned char commit_sha1[20];
-	struct strbuf buffer;
 	int encoding_is_utf8;
+	struct strbuf buffer;
 
-	git_config(git_default_config, NULL);
+	check_valid(tree, OBJ_TREE);
-
-	if (argc < 2)
-		usage(commit_tree_usage);
-	if (get_sha1(argv[1], tree_sha1))
-		die("Not a valid object name %s", argv[1]);
-
-	check_valid(tree_sha1, OBJ_TREE);
-	for (i = 2; i < argc; i += 2) {
-		unsigned char sha1[20];
-		const char *a, *b;
-		a = argv[i]; b = argv[i+1];
-		if (!b || strcmp(a, "-p"))
-			usage(commit_tree_usage);
-
-		if (get_sha1(b, sha1))
-			die("Not a valid object name %s", b);
-		check_valid(sha1, OBJ_COMMIT);
-		new_parent(lookup_commit(sha1), &parents);
-	}
 
 	/* Not having i18n.commitencoding is the same as having utf-8 */
 	encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
 
 	strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
-	strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree_sha1));
+	strbuf_addf(&buffer, "tree %s\n", sha1_to_hex(tree));
 
 	/*
 	 * NOTE! This ordering means that the same exact tree merged with a
@@ -102,14 +80,47 @@ int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 	strbuf_addch(&buffer, '\n');
 
 	/* And add the comment */
-	if (strbuf_read(&buffer, 0, 0) < 0)
+	strbuf_addstr(&buffer, msg);
-		die("git-commit-tree: read returned %s", strerror(errno));
 
 	/* And check the encoding */
 	if (encoding_is_utf8 && !is_utf8(buffer.buf))
 		fprintf(stderr, commit_utf8_warn);
 
-	if (!write_sha1_file(buffer.buf, buffer.len, commit_type, commit_sha1)) {
+	return write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
+}
+
+int cmd_commit_tree(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	struct commit_list *parents = NULL;
+	unsigned char tree_sha1[20];
+	unsigned char commit_sha1[20];
+	struct strbuf buffer = STRBUF_INIT;
+
+	git_config(git_default_config, NULL);
+
+	if (argc < 2)
+		usage(commit_tree_usage);
+	if (get_sha1(argv[1], tree_sha1))
+		die("Not a valid object name %s", argv[1]);
+
+	for (i = 2; i < argc; i += 2) {
+		unsigned char sha1[20];
+		const char *a, *b;
+		a = argv[i]; b = argv[i+1];
+		if (!b || strcmp(a, "-p"))
+			usage(commit_tree_usage);
+
+		if (get_sha1(b, sha1))
+			die("Not a valid object name %s", b);
+		check_valid(sha1, OBJ_COMMIT);
+		new_parent(lookup_commit(sha1), &parents);
+	}
+
+	if (strbuf_read(&buffer, 0, 0) < 0)
+		die("git-commit-tree: read returned %s", strerror(errno));
+
+	if (!commit_tree(buffer.buf, tree_sha1, parents, commit_sha1)) {
 		printf("%s\n", sha1_to_hex(commit_sha1));
 		return 0;
 	}

builtin-fmt-merge-msg.c

@@ -159,23 +159,24 @@ static int handle_line(char *line)
 }
 
 static void print_joined(const char *singular, const char *plural,
-		struct list *list)
+		struct list *list, struct strbuf *out)
 {
 	if (list->nr == 0)
 		return;
 	if (list->nr == 1) {
-		printf("%s%s", singular, list->list[0]);
+		strbuf_addf(out, "%s%s", singular, list->list[0]);
 	} else {
 		int i;
-		printf("%s", plural);
+		strbuf_addstr(out, plural);
 		for (i = 0; i < list->nr - 1; i++)
-			printf("%s%s", i > 0 ? ", " : "", list->list[i]);
+			strbuf_addf(out, "%s%s", i > 0 ? ", " : "", list->list[i]);
-		printf(" and %s", list->list[list->nr - 1]);
+		strbuf_addf(out, " and %s", list->list[list->nr - 1]);
 	}
 }
 
 static void shortlog(const char *name, unsigned char *sha1,
-		struct commit *head, struct rev_info *rev, int limit)
+		struct commit *head, struct rev_info *rev, int limit,
+		struct strbuf *out)
 {
 	int i, count = 0;
 	struct commit *commit;
@@ -232,15 +233,15 @@ static void shortlog(const char *name, unsigned char *sha1,
 	}
 
 	if (count > limit)
-		printf("\n* %s: (%d commits)\n", name, count);
+		strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
 	else
-		printf("\n* %s:\n", name);
+		strbuf_addf(out, "\n* %s:\n", name);
 
 	for (i = 0; i < subjects.nr; i++)
 		if (i >= limit)
-			printf("  ...\n");
+			strbuf_addf(out, "  ...\n");
 		else
-			printf("  %s\n", subjects.list[i]);
+			strbuf_addf(out, "  %s\n", subjects.list[i]);
 
 	clear_commit_marks((struct commit *)branch, flags);
 	clear_commit_marks(head, flags);
@@ -251,15 +252,105 @@ static void shortlog(const char *name, unsigned char *sha1,
 	free_list(&subjects);
 }
 
-int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
+int fmt_merge_msg(int merge_summary, struct strbuf *in, struct strbuf *out) {
-{
+	int limit = 20, i = 0, pos = 0;
-	int limit = 20, i = 0;
 	char line[1024];
-	FILE *in = stdin;
+	char *p = line, *sep = "";
-	const char *sep = "";
 	unsigned char head_sha1[20];
 	const char *current_branch;
 
+	/* get current branch */
+	current_branch = resolve_ref("HEAD", head_sha1, 1, NULL);
+	if (!current_branch)
+		die("No current branch");
+	if (!prefixcmp(current_branch, "refs/heads/"))
+		current_branch += 11;
+
+	/* get a line */
+	while (pos < in->len) {
+		int len;
+		char *newline;
+
+		p = in->buf + pos;
+		newline = strchr(p, '\n');
+		len = newline ? newline - p : strlen(p);
+		pos += len + !!newline;
+		i++;
+		p[len] = 0;
+		if (handle_line(p))
+			die ("Error in line %d: %.*s", i, len, p);
+	}
+
+	strbuf_addstr(out, "Merge ");
+	for (i = 0; i < srcs.nr; i++) {
+		struct src_data *src_data = srcs.payload[i];
+		const char *subsep = "";
+
+		strbuf_addstr(out, sep);
+		sep = "; ";
+
+		if (src_data->head_status == 1) {
+			strbuf_addstr(out, srcs.list[i]);
+			continue;
+		}
+		if (src_data->head_status == 3) {
+			subsep = ", ";
+			strbuf_addstr(out, "HEAD");
+		}
+		if (src_data->branch.nr) {
+			strbuf_addstr(out, subsep);
+			subsep = ", ";
+			print_joined("branch ", "branches ", &src_data->branch,
+					out);
+		}
+		if (src_data->r_branch.nr) {
+			strbuf_addstr(out, subsep);
+			subsep = ", ";
+			print_joined("remote branch ", "remote branches ",
+					&src_data->r_branch, out);
+		}
+		if (src_data->tag.nr) {
+			strbuf_addstr(out, subsep);
+			subsep = ", ";
+			print_joined("tag ", "tags ", &src_data->tag, out);
+		}
+		if (src_data->generic.nr) {
+			strbuf_addstr(out, subsep);
+			print_joined("commit ", "commits ", &src_data->generic,
+					out);
+		}
+		if (strcmp(".", srcs.list[i]))
+			strbuf_addf(out, " of %s", srcs.list[i]);
+	}
+
+	if (!strcmp("master", current_branch))
+		strbuf_addch(out, '\n');
+	else
+		strbuf_addf(out, " into %s\n", current_branch);
+
+	if (merge_summary) {
+		struct commit *head;
+		struct rev_info rev;
+
+		head = lookup_commit(head_sha1);
+		init_revisions(&rev, NULL);
+		rev.commit_format = CMIT_FMT_ONELINE;
+		rev.ignore_merges = 1;
+		rev.limited = 1;
+
+		for (i = 0; i < origins.nr; i++)
+			shortlog(origins.list[i], origins.payload[i],
+					head, &rev, limit, out);
+	}
+	return 0;
+}
+
+int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
+{
+	FILE *in = stdin;
+	struct strbuf input, output;
+	int ret;
+
 	git_config(fmt_merge_msg_config, NULL);
 
 	while (argc > 1) {
@@ -288,82 +379,14 @@ int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
 	if (argc > 1)
 		usage(fmt_merge_msg_usage);
 
-	/* get current branch */
+	strbuf_init(&input, 0);
-	current_branch = resolve_ref("HEAD", head_sha1, 1, NULL);
+	if (strbuf_read(&input, fileno(in), 0) < 0)
-	if (!current_branch)
+		die("could not read input file %s", strerror(errno));
-		die("No current branch");
+	strbuf_init(&output, 0);
-	if (!prefixcmp(current_branch, "refs/heads/"))
-		current_branch += 11;
-
-	while (fgets(line, sizeof(line), in)) {
-		i++;
-		if (line[0] == 0)
-			continue;
-		if (handle_line(line))
-			die ("Error in line %d: %s", i, line);
-	}
-
-	printf("Merge ");
-	for (i = 0; i < srcs.nr; i++) {
-		struct src_data *src_data = srcs.payload[i];
-		const char *subsep = "";
-
-		printf(sep);
-		sep = "; ";
-
-		if (src_data->head_status == 1) {
-			printf(srcs.list[i]);
-			continue;
-		}
-		if (src_data->head_status == 3) {
-			subsep = ", ";
-			printf("HEAD");
-		}
-		if (src_data->branch.nr) {
-			printf(subsep);
-			subsep = ", ";
-			print_joined("branch ", "branches ", &src_data->branch);
-		}
-		if (src_data->r_branch.nr) {
-			printf(subsep);
-			subsep = ", ";
-			print_joined("remote branch ", "remote branches ",
-					&src_data->r_branch);
-		}
-		if (src_data->tag.nr) {
-			printf(subsep);
-			subsep = ", ";
-			print_joined("tag ", "tags ", &src_data->tag);
-		}
-		if (src_data->generic.nr) {
-			printf(subsep);
-			print_joined("commit ", "commits ", &src_data->generic);
-		}
-		if (strcmp(".", srcs.list[i]))
-			printf(" of %s", srcs.list[i]);
-	}
-
-	if (!strcmp("master", current_branch))
-		putchar('\n');
-	else
-		printf(" into %s\n", current_branch);
-
-	if (merge_summary) {
-		struct commit *head;
-		struct rev_info rev;
-
-		head = lookup_commit(head_sha1);
-		init_revisions(&rev, prefix);
-		rev.commit_format = CMIT_FMT_ONELINE;
-		rev.ignore_merges = 1;
-		rev.limited = 1;
-
-		for (i = 0; i < origins.nr; i++)
-			shortlog(origins.list[i], origins.payload[i],
-					head, &rev, limit);
-	}
-
-	/* No cleanup yet; is standalone anyway */
 
+	ret = fmt_merge_msg(merge_summary, &input, &output);
+	if (ret)
+		return ret;
+	printf("%s", output.buf);
 	return 0;
 }

builtin-merge-recursive.c

@@ -42,14 +42,6 @@ static struct tree *shift_tree_object(struct tree *one, struct tree *two)
  * - *(int *)commit->object.sha1 set to the virtual id.
  */
 
-static unsigned commit_list_count(const struct commit_list *l)
-{
-	unsigned c = 0;
-	for (; l; l = l->next )
-		c++;
-	return c;
-}
-
 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
 {
 	struct commit *commit = xcalloc(1, sizeof(struct commit));

builtin-read-tree.c

@@ -29,30 +29,6 @@ static int list_tree(unsigned char *sha1)
 	return 0;
 }
 
-static int read_cache_unmerged(void)
-{
-	int i;
-	struct cache_entry **dst;
-	struct cache_entry *last = NULL;
-
-	read_cache();
-	dst = active_cache;
-	for (i = 0; i < active_nr; i++) {
-		struct cache_entry *ce = active_cache[i];
-		if (ce_stage(ce)) {
-			remove_name_hash(ce);
-			if (last && !strcmp(ce->name, last->name))
-				continue;
-			cache_tree_invalidate_path(active_cache_tree, ce->name);
-			last = ce;
-			continue;
-		}
-		*dst++ = ce;
-	}
-	active_nr = dst - active_cache;
-	return !!last;
-}
-
 static void prime_cache_tree_rec(struct cache_tree *it, struct tree *tree)
 {
 	struct tree_desc desc;

builtin-remote.c

@@ -29,12 +29,6 @@ static inline int postfixcmp(const char *string, const char *postfix)
 	return strcmp(string + len1 - len2, postfix);
 }
 
-static inline const char *skip_prefix(const char *name, const char *prefix)
-{
-	return !name ? "" :
-		prefixcmp(name, prefix) ?  name : name + strlen(prefix);
-}
-
 static int opt_parse_track(const struct option *opt, const char *arg, int not)
 {
 	struct path_list *list = opt->value;
@@ -182,12 +176,18 @@ static int config_read_branches(const char *key, const char *value, void *cb)
 			info->remote = xstrdup(value);
 		} else {
 			char *space = strchr(value, ' ');
-			value = skip_prefix(value, "refs/heads/");
+			const char *ptr = skip_prefix(value, "refs/heads/");
+			if (ptr)
+				value = ptr;
 			while (space) {
 				char *merge;
 				merge = xstrndup(value, space - value);
 				path_list_append(merge, &info->merge);
-				value = skip_prefix(space + 1, "refs/heads/");
+				ptr = skip_prefix(space + 1, "refs/heads/");
+				if (ptr)
+					value = ptr;
+				else
+					value = space + 1;
 				space = strchr(value, ' ');
 			}
 			path_list_append(xstrdup(value), &info->merge);
@@ -219,7 +219,12 @@ static int handle_one_branch(const char *refname,
 	refspec.dst = (char *)refname;
 	if (!remote_find_tracking(states->remote, &refspec)) {
 		struct path_list_item *item;
-		const char *name = skip_prefix(refspec.src, "refs/heads/");
+		const char *name, *ptr;
+		ptr = skip_prefix(refspec.src, "refs/heads/");
+		if (ptr)
+			name = ptr;
+		else
+			name = refspec.src;
 		/* symbolic refs pointing nowhere were handled already */
 		if ((flags & REF_ISSYMREF) ||
 				unsorted_path_list_has_path(&states->tracked,
@@ -248,6 +253,7 @@ static int get_ref_states(const struct ref *ref, struct ref_states *states)
 		struct path_list *target = &states->tracked;
 		unsigned char sha1[20];
 		void *util = NULL;
+		const char *ptr;
 
 		if (!ref->peer_ref || read_ref(ref->peer_ref->name, sha1))
 			target = &states->new;
@@ -256,8 +262,10 @@ static int get_ref_states(const struct ref *ref, struct ref_states *states)
 			if (hashcmp(sha1, ref->new_sha1))
 				util = &states;
 		}
-		path_list_append(skip_prefix(ref->name, "refs/heads/"),
+		ptr = skip_prefix(ref->name, "refs/heads/");
-				target)->util = util;
+		if (!ptr)
+			ptr = ref->name;
+		path_list_append(ptr, target)->util = util;
 	}
 	free_refs(fetch_map);
 
@@ -522,10 +530,15 @@ static int show(int argc, const char **argv)
 					"es" : "");
 			for (i = 0; i < states.remote->push_refspec_nr; i++) {
 				struct refspec *spec = states.remote->push + i;
+				const char *p = "", *q = "";
+				if (spec->src)
+					p = skip_prefix(spec->src, "refs/heads/");
+				if (spec->dst)
+					q = skip_prefix(spec->dst, "refs/heads/");
 				printf(" %s%s%s%s", spec->force ? "+" : "",
-					skip_prefix(spec->src, "refs/heads/"),
+					p ? p : spec->src,
 					spec->dst ? ":" : "",
-					skip_prefix(spec->dst, "refs/heads/"));
+					q ? q : spec->dst);
 			}
 			printf("\n");
 		}

builtin.h

@@ -2,6 +2,9 @@
 #define BUILTIN_H
 
 #include "git-compat-util.h"
+#include "strbuf.h"
+#include "cache.h"
+#include "commit.h"
 
 extern const char git_version_string[];
 extern const char git_usage_string[];
@@ -11,6 +14,10 @@ extern void list_common_cmds_help(void);
 extern void help_unknown_cmd(const char *cmd);
 extern void prune_packed_objects(int);
 extern int read_line_with_nul(char *buf, int size, FILE *file);
+extern int fmt_merge_msg(int merge_summary, struct strbuf *in,
+	struct strbuf *out);
+extern int commit_tree(const char *msg, unsigned char *tree,
+		struct commit_list *parents, unsigned char *ret);
 
 extern int cmd_add(int argc, const char **argv, const char *prefix);
 extern int cmd_annotate(int argc, const char **argv, const char *prefix);
@@ -57,6 +64,7 @@ extern int cmd_ls_tree(int argc, const char **argv, const char *prefix);
 extern int cmd_ls_remote(int argc, const char **argv, const char *prefix);
 extern int cmd_mailinfo(int argc, const char **argv, const char *prefix);
 extern int cmd_mailsplit(int argc, const char **argv, const char *prefix);
+extern int cmd_merge(int argc, const char **argv, const char *prefix);
 extern int cmd_merge_base(int argc, const char **argv, const char *prefix);
 extern int cmd_merge_ours(int argc, const char **argv, const char *prefix);
 extern int cmd_merge_file(int argc, const char **argv, const char *prefix);

cache.h

@@ -254,6 +254,7 @@ static inline void remove_name_hash(struct cache_entry *ce)
 
 #define read_cache() read_index(&the_index)
 #define read_cache_from(path) read_index_from(&the_index, (path))
+#define read_cache_unmerged() read_index_unmerged(&the_index)
 #define write_cache(newfd, cache, entries) write_index(&the_index, (newfd))
 #define discard_cache() discard_index(&the_index)
 #define unmerged_cache() unmerged_index(&the_index)
@@ -356,6 +357,7 @@ extern int init_db(const char *template_dir, unsigned int flags);
 /* Initialize and use the cache information */
 extern int read_index(struct index_state *);
 extern int read_index_from(struct index_state *, const char *path);
+extern int read_index_unmerged(struct index_state *);
 extern int write_index(const struct index_state *, int newfd);
 extern int discard_index(struct index_state *);
 extern int unmerged_index(const struct index_state *);
@@ -837,5 +839,6 @@ int report_path_error(const char *ps_matched, const char **pathspec, int prefix_
 void overlay_tree_on_cache(const char *tree_name, const char *prefix);
 
 char *alias_lookup(const char *alias);
+int split_cmdline(char *cmdline, const char ***argv);
 
 #endif /* CACHE_H */

commit.c

@@ -325,6 +325,14 @@ struct commit_list *commit_list_insert(struct commit *item, struct commit_list *
 	return new_list;
 }
 
+unsigned commit_list_count(const struct commit_list *l)
+{
+	unsigned c = 0;
+	for (; l; l = l->next )
+		c++;
+	return c;
+}
+
 void free_commit_list(struct commit_list *list)
 {
 	while (list) {
@@ -525,26 +533,34 @@ static struct commit *interesting(struct commit_list *list)
 	return NULL;
 }
 
-static struct commit_list *merge_bases(struct commit *one, struct commit *two)
+static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
 {
 	struct commit_list *list = NULL;
 	struct commit_list *result = NULL;
+	int i;
 
-	if (one == two)
+	for (i = 0; i < n; i++) {
-		/* We do not mark this even with RESULT so we do not
+		if (one == twos[i])
+			/*
+			 * We do not mark this even with RESULT so we do not
 			 * have to clean it up.
 			 */
 			return commit_list_insert(one, &result);
+	}
 
 	if (parse_commit(one))
 		return NULL;
-	if (parse_commit(two))
+	for (i = 0; i < n; i++) {
+		if (parse_commit(twos[i]))
 			return NULL;
+	}
 
 	one->object.flags |= PARENT1;
-	two->object.flags |= PARENT2;
 	insert_by_date(one, &list);
-	insert_by_date(two, &list);
+	for (i = 0; i < n; i++) {
+		twos[i]->object.flags |= PARENT2;
+		insert_by_date(twos[i], &list);
+	}
 
 	while (interesting(list)) {
 		struct commit *commit;
@@ -592,21 +608,53 @@ static struct commit_list *merge_bases(struct commit *one, struct commit *two)
 	return result;
 }
 
-struct commit_list *get_merge_bases(struct commit *one,
+struct commit_list *get_octopus_merge_bases(struct commit_list *in)
-					struct commit *two, int cleanup)
+{
+	struct commit_list *i, *j, *k, *ret = NULL;
+	struct commit_list **pptr = &ret;
+
+	for (i = in; i; i = i->next) {
+		if (!ret)
+			pptr = &commit_list_insert(i->item, pptr)->next;
+		else {
+			struct commit_list *new = NULL, *end = NULL;
+
+			for (j = ret; j; j = j->next) {
+				struct commit_list *bases;
+				bases = get_merge_bases(i->item, j->item, 1);
+				if (!new)
+					new = bases;
+				else
+					end->next = bases;
+				for (k = bases; k; k = k->next)
+					end = k;
+			}
+			ret = new;
+		}
+	}
+	return ret;
+}
+
+struct commit_list *get_merge_bases_many(struct commit *one,
+					 int n,
+					 struct commit **twos,
+					 int cleanup)
 {
 	struct commit_list *list;
 	struct commit **rslt;
 	struct commit_list *result;
 	int cnt, i, j;
 
-	result = merge_bases(one, two);
+	result = merge_bases_many(one, n, twos);
-	if (one == two)
+	for (i = 0; i < n; i++) {
+		if (one == twos[i])
 			return result;
+	}
 	if (!result || !result->next) {
 		if (cleanup) {
 			clear_commit_marks(one, all_flags);
-			clear_commit_marks(two, all_flags);
+			for (i = 0; i < n; i++)
+				clear_commit_marks(twos[i], all_flags);
 		}
 		return result;
 	}
@@ -624,12 +672,13 @@ struct commit_list *get_merge_bases(struct commit *one,
 	free_commit_list(result);
 
 	clear_commit_marks(one, all_flags);
-	clear_commit_marks(two, all_flags);
+	for (i = 0; i < n; i++)
+		clear_commit_marks(twos[i], all_flags);
 	for (i = 0; i < cnt - 1; i++) {
 		for (j = i+1; j < cnt; j++) {
 			if (!rslt[i] || !rslt[j])
 				continue;
-			result = merge_bases(rslt[i], rslt[j]);
+			result = merge_bases_many(rslt[i], 1, &rslt[j]);
 			clear_commit_marks(rslt[i], all_flags);
 			clear_commit_marks(rslt[j], all_flags);
 			for (list = result; list; list = list->next) {
@@ -651,6 +700,12 @@ struct commit_list *get_merge_bases(struct commit *one,
 	return result;
 }
 
+struct commit_list *get_merge_bases(struct commit *one, struct commit *two,
+				    int cleanup)
+{
+	return get_merge_bases_many(one, 1, &two, cleanup);
+}
+
 int in_merge_bases(struct commit *commit, struct commit **reference, int num)
 {
 	struct commit_list *bases, *b;
@@ -670,3 +725,55 @@ int in_merge_bases(struct commit *commit, struct commit **reference, int num)
 	free_commit_list(bases);
 	return ret;
 }
+
+struct commit_list *reduce_heads(struct commit_list *heads)
+{
+	struct commit_list *p;
+	struct commit_list *result = NULL, **tail = &result;
+	struct commit **other;
+	size_t num_head, num_other;
+
+	if (!heads)
+		return NULL;
+
+	/* Avoid unnecessary reallocations */
+	for (p = heads, num_head = 0; p; p = p->next)
+		num_head++;
+	other = xcalloc(sizeof(*other), num_head);
+
+	/* For each commit, see if it can be reached by others */
+	for (p = heads; p; p = p->next) {
+		struct commit_list *q, *base;
+
+		/* Do we already have this in the result? */
+		for (q = result; q; q = q->next)
+			if (p->item == q->item)
+				break;
+		if (q)
+			continue;
+
+		num_other = 0;
+		for (q = heads; q; q = q->next) {
+			if (p->item == q->item)
+				continue;
+			other[num_other++] = q->item;
+		}
+		if (num_other)
+			base = get_merge_bases_many(p->item, num_other, other, 1);
+		else
+			base = NULL;
+		/*
+		 * If p->item does not have anything common with other
+		 * commits, there won't be any merge base.  If it is
+		 * reachable from some of the others, p->item will be
+		 * the merge base.  If its history is connected with
+		 * others, but p->item is not reachable by others, we
+		 * will get something other than p->item back.
+		 */
+		if (!base || (base->item != p->item))
+			tail = &(commit_list_insert(p->item, tail)->next);
+		free_commit_list(base);
+	}
+	free(other);
+	return result;
+}

commit.h

@@ -41,6 +41,7 @@ int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size);
 int parse_commit(struct commit *item);
 
 struct commit_list * commit_list_insert(struct commit *item, struct commit_list **list_p);
+unsigned commit_list_count(const struct commit_list *l);
 struct commit_list * insert_by_date(struct commit *item, struct commit_list **list);
 
 void free_commit_list(struct commit_list *list);
@@ -120,6 +121,7 @@ int read_graft_file(const char *graft_file);
 struct commit_graft *lookup_commit_graft(const unsigned char *sha1);
 
 extern struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2, int cleanup);
+extern struct commit_list *get_octopus_merge_bases(struct commit_list *in);
 
 extern int register_shallow(const unsigned char *sha1);
 extern int unregister_shallow(const unsigned char *sha1);
@@ -137,4 +139,6 @@ static inline int single_parent(struct commit *commit)
 	return commit->parents && !commit->parents->next;
 }
 
+struct commit_list *reduce_heads(struct commit_list *heads);
+
 #endif /* COMMIT_H */

git-compat-util.h

@@ -157,6 +157,12 @@ extern void set_warn_routine(void (*routine)(const char *warn, va_list params));
 extern int prefixcmp(const char *str, const char *prefix);
 extern time_t tm_to_time_t(const struct tm *tm);
 
+static inline const char *skip_prefix(const char *str, const char *prefix)
+{
+	size_t len = strlen(prefix);
+	return strncmp(str, prefix, len) ? NULL : str + len;
+}
+
 #ifdef NO_MMAP
 
 #ifndef PROT_READ

git.c

@@ -127,59 +127,6 @@ static int handle_options(const char*** argv, int* argc, int* envchanged)
 	return handled;
 }
 
-static int split_cmdline(char *cmdline, const char ***argv)
-{
-	int src, dst, count = 0, size = 16;
-	char quoted = 0;
-
-	*argv = xmalloc(sizeof(char*) * size);
-
-	/* split alias_string */
-	(*argv)[count++] = cmdline;
-	for (src = dst = 0; cmdline[src];) {
-		char c = cmdline[src];
-		if (!quoted && isspace(c)) {
-			cmdline[dst++] = 0;
-			while (cmdline[++src]
-					&& isspace(cmdline[src]))
-				; /* skip */
-			if (count >= size) {
-				size += 16;
-				*argv = xrealloc(*argv, sizeof(char*) * size);
-			}
-			(*argv)[count++] = cmdline + dst;
-		} else if(!quoted && (c == '\'' || c == '"')) {
-			quoted = c;
-			src++;
-		} else if (c == quoted) {
-			quoted = 0;
-			src++;
-		} else {
-			if (c == '\\' && quoted != '\'') {
-				src++;
-				c = cmdline[src];
-				if (!c) {
-					free(*argv);
-					*argv = NULL;
-					return error("cmdline ends with \\");
-				}
-			}
-			cmdline[dst++] = c;
-			src++;
-		}
-	}
-
-	cmdline[dst] = 0;
-
-	if (quoted) {
-		free(*argv);
-		*argv = NULL;
-		return error("unclosed quote");
-	}
-
-	return count;
-}
-
 static int handle_alias(int *argcp, const char ***argv)
 {
 	int envchanged = 0, ret = 0, saved_errno = errno;
@@ -366,6 +313,7 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "ls-remote", cmd_ls_remote },
 		{ "mailinfo", cmd_mailinfo },
 		{ "mailsplit", cmd_mailsplit },
+		{ "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 		{ "merge-base", cmd_merge_base, RUN_SETUP },
 		{ "merge-file", cmd_merge_file },
 		{ "merge-ours", cmd_merge_ours, RUN_SETUP },

parse-options.c

@@ -5,12 +5,6 @@
 #define OPT_SHORT 1
 #define OPT_UNSET 2
 
-static inline const char *skip_prefix(const char *str, const char *prefix)
-{
-	size_t len = strlen(prefix);
-	return strncmp(str, prefix, len) ? NULL : str + len;
-}
-
 static int opterror(const struct option *opt, const char *reason, int flags)
 {
 	if (flags & OPT_SHORT)

read-cache.c

@@ -1410,3 +1410,34 @@ int write_index(const struct index_state *istate, int newfd)
 	}
 	return ce_flush(&c, newfd);
 }
+
+/*
+ * Read the index file that is potentially unmerged into given
+ * index_state, dropping any unmerged entries.  Returns true is
+ * the index is unmerged.  Callers who want to refuse to work
+ * from an unmerged state can call this and check its return value,
+ * instead of calling read_cache().
+ */
+int read_index_unmerged(struct index_state *istate)
+{
+	int i;
+	struct cache_entry **dst;
+	struct cache_entry *last = NULL;
+
+	read_index(istate);
+	dst = istate->cache;
+	for (i = 0; i < istate->cache_nr; i++) {
+		struct cache_entry *ce = istate->cache[i];
+		if (ce_stage(ce)) {
+			remove_name_hash(ce);
+			if (last && !strcmp(ce->name, last->name))
+				continue;
+			cache_tree_invalidate_path(istate->cache_tree, ce->name);
+			last = ce;
+			continue;
+		}
+		*dst++ = ce;
+	}
+	istate->cache_nr = dst - istate->cache;
+	return !!last;
+}

t/t6021-merge-criss-cross.sh

@@ -89,4 +89,8 @@ EOF
 
 test_expect_success 'Criss-cross merge result' 'cmp file file-expect'
 
+test_expect_success 'Criss-cross merge fails (-s resolve)' \
+'git reset --hard A^ &&
+test_must_fail git merge -s resolve -m "final merge" B'
+
 test_done

t/t7600-merge.sh

@@ -465,11 +465,51 @@ test_expect_success 'merge log message' '
 	git merge --no-log c2 &&
 	git show -s --pretty=format:%b HEAD >msg.act &&
 	verify_diff msg.nolog msg.act "[OOPS] bad merge log message" &&
+
 	git merge --log c3 &&
 	git show -s --pretty=format:%b HEAD >msg.act &&
+	verify_diff msg.log msg.act "[OOPS] bad merge log message" &&
+
+	git reset --hard HEAD^ &&
+	git config merge.log yes &&
+	git merge c3 &&
+	git show -s --pretty=format:%b HEAD >msg.act &&
 	verify_diff msg.log msg.act "[OOPS] bad merge log message"
 '
 
 test_debug 'gitk --all'
 
+test_expect_success 'merge c1 with c0, c2, c0, and c1' '
+       git reset --hard c1 &&
+       git config branch.master.mergeoptions "" &&
+       test_tick &&
+       git merge c0 c2 c0 c1 &&
+       verify_merge file result.1-5 &&
+       verify_parents $c1 $c2
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c0, c2, c0, and c1' '
+       git reset --hard c1 &&
+       git config branch.master.mergeoptions "" &&
+       test_tick &&
+       git merge c0 c2 c0 c1 &&
+       verify_merge file result.1-5 &&
+       verify_parents $c1 $c2
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c1 and c2' '
+       git reset --hard c1 &&
+       git config branch.master.mergeoptions "" &&
+       test_tick &&
+       git merge c1 c2 &&
+       verify_merge file result.1-5 &&
+       verify_parents $c1 $c2
+'
+
+test_debug 'gitk --all'
+
 test_done

t/t7601-merge-pull-config.sh

@@ -0,0 +1,129 @@
+#!/bin/sh
+
+test_description='git-merge
+
+Testing pull.* configuration parsing.'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	echo c0 >c0.c &&
+	git add c0.c &&
+	git commit -m c0 &&
+	git tag c0 &&
+	echo c1 >c1.c &&
+	git add c1.c &&
+	git commit -m c1 &&
+	git tag c1 &&
+	git reset --hard c0 &&
+	echo c2 >c2.c &&
+	git add c2.c &&
+	git commit -m c2 &&
+	git tag c2 &&
+	git reset --hard c0 &&
+	echo c3 >c3.c &&
+	git add c3.c &&
+	git commit -m c3 &&
+	git tag c3
+'
+
+test_expect_success 'merge c1 with c2' '
+	git reset --hard c1 &&
+	test -f c0.c &&
+	test -f c1.c &&
+	test ! -f c2.c &&
+	test ! -f c3.c &&
+	git merge c2 &&
+	test -f c1.c &&
+	test -f c2.c
+'
+
+test_expect_success 'merge c1 with c2 (ours in pull.twohead)' '
+	git reset --hard c1 &&
+	git config pull.twohead ours &&
+	git merge c2 &&
+	test -f c1.c &&
+	! test -f c2.c
+'
+
+test_expect_success 'merge c1 with c2 and c3 (recursive in pull.octopus)' '
+	git reset --hard c1 &&
+	git config pull.octopus "recursive" &&
+	test_must_fail git merge c2 c3 &&
+	test "$(git rev-parse c1)" = "$(git rev-parse HEAD)"
+'
+
+test_expect_success 'merge c1 with c2 and c3 (recursive and octopus in pull.octopus)' '
+	git reset --hard c1 &&
+	git config pull.octopus "recursive octopus" &&
+	git merge c2 c3 &&
+	test "$(git rev-parse c1)" != "$(git rev-parse HEAD)" &&
+	test "$(git rev-parse c1)" = "$(git rev-parse HEAD^1)" &&
+	test "$(git rev-parse c2)" = "$(git rev-parse HEAD^2)" &&
+	test "$(git rev-parse c3)" = "$(git rev-parse HEAD^3)" &&
+	git diff --exit-code &&
+	test -f c0.c &&
+	test -f c1.c &&
+	test -f c2.c &&
+	test -f c3.c
+'
+
+conflict_count()
+{
+	{
+		git diff-files --name-only
+		git ls-files --unmerged
+	} | wc -l
+}
+
+# c4 - c5
+#    \ c6
+#
+# There are two conflicts here:
+#
+# 1) Because foo.c is renamed to bar.c, recursive will handle this,
+# resolve won't.
+#
+# 2) One in conflict.c and that will always fail.
+
+test_expect_success 'setup conflicted merge' '
+	git reset --hard c0 &&
+	echo A >conflict.c &&
+	git add conflict.c &&
+	echo contents >foo.c &&
+	git add foo.c &&
+	git commit -m c4 &&
+	git tag c4 &&
+	echo B >conflict.c &&
+	git add conflict.c &&
+	git mv foo.c bar.c &&
+	git commit -m c5 &&
+	git tag c5 &&
+	git reset --hard c4 &&
+	echo C >conflict.c &&
+	git add conflict.c &&
+	echo secondline >> foo.c &&
+	git add foo.c &&
+	git commit -m c6 &&
+	git tag c6
+'
+
+# First do the merge with resolve and recursive then verify that
+# recusive is choosen.
+
+test_expect_success 'merge picks up the best result' '
+	git config pull.twohead "recursive resolve" &&
+	git reset --hard c5 &&
+	git merge -s resolve c6
+	resolve_count=$(conflict_count) &&
+	git reset --hard c5 &&
+	git merge -s recursive c6
+	recursive_count=$(conflict_count) &&
+	git reset --hard c5 &&
+	git merge c6
+	auto_count=$(conflict_count) &&
+	test $auto_count = $recursive_count &&
+	test $auto_count != $resolve_count
+'
+
+test_done

t/t7602-merge-octopus-many.sh

@@ -0,0 +1,52 @@
+#!/bin/sh
+
+test_description='git-merge
+
+Testing octopus merge with more than 25 refs.'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	echo c0 > c0.c &&
+	git add c0.c &&
+	git commit -m c0 &&
+	git tag c0 &&
+	i=1 &&
+	while test $i -le 30
+	do
+		git reset --hard c0 &&
+		echo c$i > c$i.c &&
+		git add c$i.c &&
+		git commit -m c$i &&
+		git tag c$i &&
+		i=`expr $i + 1` || return 1
+	done
+'
+
+test_expect_success 'merge c1 with c2, c3, c4, ... c29' '
+	git reset --hard c1 &&
+	i=2 &&
+	refs="" &&
+	while test $i -le 30
+	do
+		refs="$refs c$i"
+		i=`expr $i + 1`
+	done
+	git merge $refs &&
+	test "$(git rev-parse c1)" != "$(git rev-parse HEAD)" &&
+	i=1 &&
+	while test $i -le 30
+	do
+		test "$(git rev-parse c$i)" = "$(git rev-parse HEAD^$i)" &&
+		i=`expr $i + 1` || return 1
+	done &&
+	git diff --exit-code &&
+	i=1 &&
+	while test $i -le 30
+	do
+		test -f c$i.c &&
+		i=`expr $i + 1` || return 1
+	done
+'
+
+test_done

t/t7603-merge-reduce-heads.sh

@@ -0,0 +1,63 @@
+#!/bin/sh
+
+test_description='git-merge
+
+Testing octopus merge when reducing parents to independent branches.'
+
+. ./test-lib.sh
+
+# 0 - 1
+#   \ 2
+#   \ 3
+#   \ 4 - 5
+#
+# So 1, 2, 3 and 5 should be kept, 4 should be avoided.
+
+test_expect_success 'setup' '
+	echo c0 > c0.c &&
+	git add c0.c &&
+	git commit -m c0 &&
+	git tag c0 &&
+	echo c1 > c1.c &&
+	git add c1.c &&
+	git commit -m c1 &&
+	git tag c1 &&
+	git reset --hard c0 &&
+	echo c2 > c2.c &&
+	git add c2.c &&
+	git commit -m c2 &&
+	git tag c2 &&
+	git reset --hard c0 &&
+	echo c3 > c3.c &&
+	git add c3.c &&
+	git commit -m c3 &&
+	git tag c3 &&
+	git reset --hard c0 &&
+	echo c4 > c4.c &&
+	git add c4.c &&
+	git commit -m c4 &&
+	git tag c4 &&
+	echo c5 > c5.c &&
+	git add c5.c &&
+	git commit -m c5 &&
+	git tag c5
+'
+
+test_expect_success 'merge c1 with c2, c3, c4, c5' '
+	git reset --hard c1 &&
+	git merge c2 c3 c4 c5 &&
+	test "$(git rev-parse c1)" != "$(git rev-parse HEAD)" &&
+	test "$(git rev-parse c1)" = "$(git rev-parse HEAD^1)" &&
+	test "$(git rev-parse c2)" = "$(git rev-parse HEAD^2)" &&
+	test "$(git rev-parse c3)" = "$(git rev-parse HEAD^3)" &&
+	test "$(git rev-parse c5)" = "$(git rev-parse HEAD^4)" &&
+	git diff --exit-code &&
+	test -f c0.c &&
+	test -f c1.c &&
+	test -f c2.c &&
+	test -f c3.c &&
+	test -f c4.c &&
+	test -f c5.c
+'
+
+test_done

t/t7604-merge-custom-message.sh

@@ -0,0 +1,37 @@
+#!/bin/sh
+
+test_description='git-merge
+
+Testing merge when using a custom message for the merge commit.'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	echo c0 > c0.c &&
+	git add c0.c &&
+	git commit -m c0 &&
+	git tag c0 &&
+	echo c1 > c1.c &&
+	git add c1.c &&
+	git commit -m c1 &&
+	git tag c1 &&
+	git reset --hard c0 &&
+	echo c2 > c2.c &&
+	git add c2.c &&
+	git commit -m c2 &&
+	git tag c2
+'
+
+cat >expected <<\EOF
+custom message
+
+Merge commit 'c2'
+EOF
+test_expect_success 'merge c2 with a custom message' '
+	git reset --hard c1 &&
+	git merge -m "custom message" c2 &&
+	git cat-file commit HEAD | sed -e "1,/^$/d" > actual &&
+	test_cmp expected actual
+'
+
+test_done

t/t7605-merge-resolve.sh

@@ -0,0 +1,46 @@
+#!/bin/sh
+
+test_description='git-merge
+
+Testing the resolve strategy.'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	echo c0 > c0.c &&
+	git add c0.c &&
+	git commit -m c0 &&
+	git tag c0 &&
+	echo c1 > c1.c &&
+	git add c1.c &&
+	git commit -m c1 &&
+	git tag c1 &&
+	git reset --hard c0 &&
+	echo c2 > c2.c &&
+	git add c2.c &&
+	git commit -m c2 &&
+	git tag c2 &&
+	git reset --hard c0 &&
+	echo c3 > c2.c &&
+	git add c2.c &&
+	git commit -m c3 &&
+	git tag c3
+'
+
+test_expect_success 'merge c1 to c2' '
+	git reset --hard c1 &&
+	git merge -s resolve c2 &&
+	test "$(git rev-parse c1)" != "$(git rev-parse HEAD)" &&
+	test "$(git rev-parse c1)" = "$(git rev-parse HEAD^1)" &&
+	test "$(git rev-parse c2)" = "$(git rev-parse HEAD^2)" &&
+	git diff --exit-code &&
+	test -f c0.c &&
+	test -f c1.c &&
+	test -f c2.c
+'
+
+test_expect_success 'merge c2 to c3 (fails)' '
+	git reset --hard c2 &&
+	test_must_fail git merge -s resolve c3
+'
+test_done