Make git-fmt-merge-msg a builtin

Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 355 insertions, 0 deletions

diff --git a/builtin-fmt-merge-msg.c b/builtin-fmt-merge-msg.c
new file mode 100644
index 000000000..65274824d
--- /dev/null
+++ b/builtin-fmt-merge-msg.c
@@ -0,0 +1,355 @@
+#include "cache.h"
+#include "commit.h"
+#include "diff.h"
+#include "revision.h"
+#include "tag.h"
+
+static const char *fmt_merge_msg_usage =
+	"git-fmt-merge-msg [--summary] [--no-summary] [--file <file>]";
+
+static int merge_summary = 0;
+
+static int fmt_merge_msg_config(const char *key, const char *value)
+{
+	if (!strcmp("merge.summary", key))
+		merge_summary = git_config_bool(key, value);
+	return 0;
+}
+
+struct list {
+	char **list;
+	void **payload;
+	unsigned nr, alloc;
+};
+
+static void append_to_list(struct list *list, char *value, void *payload)
+{
+	if (list->nr == list->alloc) {
+		list->alloc += 32;
+		list->list = realloc(list->list, sizeof(char *) * list->alloc);
+		list->payload = realloc(list->payload,
+				sizeof(char *) * list->alloc);
+	}
+	list->payload[list->nr] = payload;
+	list->list[list->nr++] = value;
+}
+
+static int find_in_list(struct list *list, char *value)
+{
+	int i;
+
+	for (i = 0; i < list->nr; i++)
+		if (!strcmp(list->list[i], value))
+			return i;
+
+	return -1;
+}
+
+static void free_list(struct list *list)
+{
+	int i;
+
+	if (list->alloc == 0)
+		return;
+
+	for (i = 0; i < list->nr; i++) {
+		free(list->list[i]);
+		if (list->payload[i])
+			free(list->payload[i]);
+	}
+	free(list->list);
+	free(list->payload);
+	list->nr = list->alloc = 0;
+}
+
+struct src_data {
+	struct list branch, tag, r_branch, generic;
+	int head_status;
+};
+
+static struct list srcs = { NULL, NULL, 0, 0};
+static struct list origins = { NULL, NULL, 0, 0};
+
+static int handle_line(char *line)
+{
+	int i, len = strlen(line);
+	unsigned char *sha1;
+	char *src, *origin;
+	struct src_data *src_data;
+
+	if (len < 43 || line[40] != '\t')
+		return 1;
+
+	if (!strncmp(line + 41, "not-for-merge", 13))
+		return 0;
+
+	if (line[41] != '\t')
+		return 2;
+
+	line[40] = 0;
+	sha1 = xmalloc(20);
+	i = get_sha1(line, sha1);
+	line[40] = '\t';
+	if (i)
+		return 3;
+
+	if (line[len - 1] == '\n')
+		line[len - 1] = 0;
+	line += 42;
+
+	src = strstr(line, " of ");
+	if (src) {
+		*src = 0;
+		src += 4;
+	} else
+		src = "HEAD";
+
+	i = find_in_list(&srcs, src);
+	if (i < 0) {
+		i = srcs.nr;
+		append_to_list(&srcs, strdup(src),
+				xcalloc(1, sizeof(struct src_data)));
+	}
+	src_data = srcs.payload[i];
+
+	if (!strncmp(line, "branch ", 7)) {
+		origin = strdup(line + 7);
+		append_to_list(&src_data->branch, origin, NULL);
+		src_data->head_status |= 2;
+	} else if (!strncmp(line, "tag ", 4)) {
+		origin = line;
+		append_to_list(&src_data->tag, strdup(origin + 4), NULL);
+		src_data->head_status |= 2;
+	} else if (!strncmp(line, "remote branch ", 14)) {
+		origin = strdup(line + 14);
+		append_to_list(&src_data->r_branch, origin, NULL);
+		src_data->head_status |= 2;
+	} else if (!strcmp(line, "HEAD")) {
+		origin = strdup(src);
+		src_data->head_status |= 1;
+	} else {
+		origin = strdup(src);
+		append_to_list(&src_data->generic, strdup(line), NULL);
+		src_data->head_status |= 2;
+	}
+
+	if (!strcmp(".", src) || !strcmp(src, origin)) {
+		int len = strlen(origin);
+		if (origin[0] == '\'' && origin[len - 1] == '\'') {
+			char *new_origin = malloc(len - 1);
+			memcpy(new_origin, origin + 1, len - 2);
+			new_origin[len - 1] = 0;
+			origin = new_origin;
+		} else
+			origin = strdup(origin);
+	} else {
+		char *new_origin = malloc(strlen(origin) + strlen(src) + 5);
+		sprintf(new_origin, "%s of %s", origin, src);
+		origin = new_origin;
+	}
+	append_to_list(&origins, origin, sha1);
+	return 0;
+}
+
+static void print_joined(const char *singular, const char *plural,
+		struct list *list)
+{
+	if (list->nr == 0)
+		return;
+	if (list->nr == 1) {
+		printf("%s%s", singular, list->list[0]);
+	} else {
+		int i;
+		printf("%s", plural);
+		for (i = 0; i < list->nr - 1; i++)
+			printf("%s%s", i > 0 ? ", " : "", list->list[i]);
+		printf(" 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)
+{
+	int i, count = 0;
+	struct commit *commit;
+	struct object *branch;
+	struct list subjects = { NULL, NULL, 0, 0 };
+	int flags = UNINTERESTING | TREECHANGE | SEEN | SHOWN | ADDED;
+
+	branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
+	if (!branch || branch->type != TYPE_COMMIT)
+		return;
+
+	setup_revisions(0, NULL, rev, NULL);
+	rev->ignore_merges = 1;
+	add_pending_object(rev, branch, name);
+	add_pending_object(rev, &head->object, "^HEAD");
+	head->object.flags |= UNINTERESTING;
+	prepare_revision_walk(rev);
+	while ((commit = get_revision(rev)) != NULL) {
+		char *oneline, *bol, *eol;
+
+		/* ignore merges */
+		if (commit->parents && commit->parents->next)
+			continue;
+
+		count++;
+		if (subjects.nr > limit)
+			continue;
+
+		bol = strstr(commit->buffer, "\n\n");
+		if (!bol) {
+			append_to_list(&subjects, strdup(sha1_to_hex(
+							commit->object.sha1)),
+					NULL);
+			continue;
+		}
+
+		bol += 2;
+		eol = strchr(bol, '\n');
+
+		if (eol) {
+			int len = eol - bol;
+			oneline = malloc(len + 1);
+			memcpy(oneline, bol, len);
+			oneline[len] = 0;
+		} else
+			oneline = strdup(bol);
+		append_to_list(&subjects, oneline, NULL);
+	}
+
+	if (count > limit)
+		printf("\n* %s: (%d commits)\n", name, count);
+	else
+		printf("\n* %s:\n", name);
+
+	for (i = 0; i < subjects.nr; i++)
+		if (i >= limit)
+			printf("  ...\n");
+		else
+			printf("  %s\n", subjects.list[i]);
+
+	clear_commit_marks((struct commit *)branch, flags);
+	clear_commit_marks(head, flags);
+	free_commit_list(rev->commits);
+	rev->commits = NULL;
+	rev->pending.nr = 0;
+
+	free_list(&subjects);
+}
+
+int cmd_fmt_merge_msg(int argc, char **argv, char **envp)
+{
+	int limit = 20, i = 0;
+	char line[1024];
+	FILE *in = stdin;
+	const char *sep = "";
+	unsigned char head_sha1[20];
+	const char *head, *current_branch;
+
+	git_config(fmt_merge_msg_config);
+
+	while (argc > 1) {
+		if (!strcmp(argv[1], "--summary"))
+			merge_summary = 1;
+		else if (!strcmp(argv[1], "--no-summary"))
+			merge_summary = 0;
+		else if (!strcmp(argv[1], "-F") || !strcmp(argv[1], "--file")) {
+			if (argc < 2)
+				die ("Which file?");
+			if (!strcmp(argv[2], "-"))
+				in = stdin;
+			else {
+				fclose(in);
+				in = fopen(argv[2], "r");
+			}
+			argc--; argv++;
+		} else
+			break;
+		argc--; argv++;
+	}
+
+	if (argc > 1)
+		usage(fmt_merge_msg_usage);
+
+	/* get current branch */
+	head = strdup(git_path("HEAD"));
+	current_branch = resolve_ref(head, head_sha1, 1);
+	current_branch += strlen(head) - 4;
+	free((char *)head);
+	if (!strncmp(current_branch, "refs/heads/", 11))
+		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);
+		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 */
+
+	return 0;
+}
+