Port git commit to C.

This makes git commit a builtin and moves git-commit.sh to
contrib/examples.  This also removes the git-runstatus
helper, which was mostly just a git-status.sh implementation detail.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 614 insertions, 0 deletions

diff --git a/builtin-commit.c b/builtin-commit.c
new file mode 100644
index 0000000000..669cc6b6f1
--- /dev/null
+++ b/builtin-commit.c
@@ -0,0 +1,614 @@
+/*
+ * Builtin "git commit"
+ *
+ * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>
+ * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
+ */
+
+#include "cache.h"
+#include "cache-tree.h"
+#include "builtin.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "commit.h"
+#include "revision.h"
+#include "wt-status.h"
+#include "run-command.h"
+#include "refs.h"
+#include "log-tree.h"
+#include "strbuf.h"
+#include "utf8.h"
+#include "parse-options.h"
+
+static const char * const builtin_commit_usage[] = {
+	"git-commit [options] [--] <filepattern>...",
+	NULL
+};
+
+static unsigned char head_sha1[20], merge_head_sha1[20];
+static char *use_message_buffer;
+static const char commit_editmsg[] = "COMMIT_EDITMSG";
+static struct lock_file lock_file;
+
+static char *logfile, *force_author, *message, *template_file;
+static char *edit_message, *use_message;
+static int all, edit_flag, also, interactive, only, amend, signoff;
+static int quiet, verbose, untracked_files, no_verify;
+
+static int no_edit, initial_commit, in_merge;
+const char *only_include_assumed;
+
+static struct option builtin_commit_options[] = {
+	OPT__QUIET(&quiet),
+	OPT__VERBOSE(&verbose),
+	OPT_GROUP("Commit message options"),
+
+	OPT_STRING('F', "file", &logfile, "FILE", "read log from file"),
+	OPT_STRING(0, "author", &force_author, "AUTHOR", "override author for commit"),
+	OPT_STRING('m', "message", &message, "MESSAGE", "specify commit message"),
+	OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit "),
+	OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
+	OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by: header"),
+	OPT_STRING('t', "template", &template_file, "FILE", "use specified template file"),
+	OPT_BOOLEAN('e', "edit", &edit_flag, "force edit of commit"),
+
+	OPT_GROUP("Commit contents options"),
+	OPT_BOOLEAN('a', "all", &all, "commit all changed files"),
+	OPT_BOOLEAN('i', "include", &also, "add specified files to index for commit"),
+	OPT_BOOLEAN(0, "interactive", &interactive, "interactively add files"),
+	OPT_BOOLEAN('o', "only", &only, ""),
+	OPT_BOOLEAN('n', "no-verify", &no_verify, "bypass pre-commit hook"),
+	OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
+	OPT_BOOLEAN(0, "untracked-files", &untracked_files, "show all untracked files"),
+
+	OPT_END()
+};
+
+static char *prepare_index(const char **files, const char *prefix)
+{
+	int fd;
+	struct tree *tree;
+	struct lock_file *next_index_lock;
+
+	if (interactive) {
+		interactive_add();
+		return get_index_file();
+	}
+
+	fd = hold_locked_index(&lock_file, 1);
+	if (read_cache() < 0)
+		die("index file corrupt");
+
+	if (all || also) {
+		add_files_to_cache(verbose, also ? prefix : NULL, files);
+		if (write_cache(fd, active_cache, active_nr) || close(fd))
+			die("unable to write new_index file");
+		return lock_file.filename;
+	}
+
+	if (*files == NULL) {
+		/* Commit index as-is. */
+		rollback_lock_file(&lock_file);
+		return get_index_file();
+	}
+
+	/* update the user index file */
+	add_files_to_cache(verbose, prefix, files);
+	if (write_cache(fd, active_cache, active_nr) || close(fd))
+		die("unable to write new_index file");
+
+	if (!initial_commit) {
+		tree = parse_tree_indirect(head_sha1);
+		if (!tree)
+			die("failed to unpack HEAD tree object");
+		if (read_tree(tree, 0, NULL))
+			die("failed to read HEAD tree object");
+	}
+
+	/* Use a lock file to garbage collect the temporary index file. */
+	next_index_lock = xmalloc(sizeof(*next_index_lock));
+	fd = hold_lock_file_for_update(next_index_lock,
+				       git_path("next-index-%d", getpid()), 1);
+	add_files_to_cache(verbose, prefix, files);
+	if (write_cache(fd, active_cache, active_nr) || close(fd))
+		die("unable to write new_index file");
+
+	return next_index_lock->filename;
+}
+
+static int run_status(FILE *fp, const char *index_file)
+{
+	struct wt_status s;
+
+	wt_status_prepare(&s);
+
+	if (amend) {
+		s.amend = 1;
+		s.reference = "HEAD^1";
+	}
+	s.verbose = verbose;
+	s.untracked = untracked_files;
+	s.index_file = index_file;
+	s.fp = fp;
+
+	wt_status_print(&s);
+
+	return s.commitable;
+}
+
+static const char sign_off_header[] = "Signed-off-by: ";
+
+static int prepare_log_message(const char *index_file)
+{
+	struct stat statbuf;
+	int commitable;
+	struct strbuf sb;
+	char *buffer;
+	FILE *fp;
+
+	strbuf_init(&sb, 0);
+	if (message) {
+		strbuf_add(&sb, message, strlen(message));
+	} else if (logfile && !strcmp(logfile, "-")) {
+		if (isatty(0))
+			fprintf(stderr, "(reading log message from standard input)\n");
+		if (strbuf_read(&sb, 0, 0) < 0)
+			die("could not read log from standard input");
+	} else if (logfile) {
+		if (strbuf_read_file(&sb, logfile, 0) < 0)
+			die("could not read log file '%s': %s",
+			    logfile, strerror(errno));
+	} else if (use_message) {
+		buffer = strstr(use_message_buffer, "\n\n");
+		if (!buffer || buffer[2] == '\0')
+			die("commit has empty message");
+		strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
+	} else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
+		if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
+			die("could not read MERGE_MSG: %s", strerror(errno));
+	} else if (!stat(git_path("SQUASH_MSG"), &statbuf)) {
+		if (strbuf_read_file(&sb, git_path("SQUASH_MSG"), 0) < 0)
+			die("could not read SQUASH_MSG: %s", strerror(errno));
+	} else if (template_file && !stat(template_file, &statbuf)) {
+		if (strbuf_read_file(&sb, template_file, 0) < 0)
+			die("could not read %s: %s",
+			    template_file, strerror(errno));
+	}
+
+	fp = fopen(git_path(commit_editmsg), "w");
+	if (fp == NULL)
+		die("could not open %s\n", git_path(commit_editmsg));
+
+	stripspace(&sb, 0);
+	if (fwrite(sb.buf, 1, sb.len, fp) < sb.len)
+		die("could not write commit template: %s\n",
+		    strerror(errno));
+
+	if (signoff) {
+		const char *info, *bol;
+
+		info = git_committer_info(1);
+		strbuf_addch(&sb, '\0');
+		bol = strrchr(sb.buf + sb.len - 1, '\n');
+		if (!bol || prefixcmp(bol, sign_off_header))
+			fprintf(fp, "\n");
+		fprintf(fp, "%s%s\n", sign_off_header, git_committer_info(1));
+	}
+
+	strbuf_release(&sb);
+
+	if (in_merge && !no_edit)
+		fprintf(fp,
+			"#\n"
+			"# It looks like you may be committing a MERGE.\n"
+			"# If this is not correct, please remove the file\n"
+			"#	%s\n"
+			"# and try again.\n"
+			"#\n",
+			git_path("MERGE_HEAD"));
+
+	fprintf(fp,
+		"\n"
+		"# Please enter the commit message for your changes.\n"
+		"# (Comment lines starting with '#' will not be included)\n");
+	if (only_include_assumed)
+		fprintf(fp, "# %s\n", only_include_assumed);
+
+	commitable = run_status(fp, index_file);
+
+	fclose(fp);
+
+	return commitable;
+}
+
+/*
+ * Find out if the message starting at position 'start' in the strbuf
+ * contains only whitespace and Signed-off-by lines.
+ */
+static int message_is_empty(struct strbuf *sb, int start)
+{
+	struct strbuf tmpl;
+	const char *nl;
+	int eol, i;
+
+	/* See if the template is just a prefix of the message. */
+	strbuf_init(&tmpl, 0);
+	if (template_file && strbuf_read_file(&tmpl, template_file, 0) > 0) {
+		stripspace(&tmpl, 1);
+		if (start + tmpl.len <= sb->len &&
+		    memcmp(tmpl.buf, sb->buf + start, tmpl.len) == 0)
+			start += tmpl.len;
+	}
+	strbuf_release(&tmpl);
+
+	/* Check if the rest is just whitespace and Signed-of-by's. */
+	for (i = start; i < sb->len; i++) {
+		nl = memchr(sb->buf + i, '\n', sb->len - i);
+		if (nl)
+			eol = nl - sb->buf;
+		else
+			eol = sb->len;
+
+		if (strlen(sign_off_header) <= eol - i &&
+		    !prefixcmp(sb->buf + i, sign_off_header)) {
+			i = eol;
+			continue;
+		}
+		while (i < eol)
+			if (!isspace(sb->buf[i++]))
+				return 0;
+	}
+
+	return 1;
+}
+
+static void determine_author_info(struct strbuf *sb)
+{
+	char *name, *email, *date;
+
+	name = getenv("GIT_AUTHOR_NAME");
+	email = getenv("GIT_AUTHOR_EMAIL");
+	date = getenv("GIT_AUTHOR_DATE");
+
+	if (use_message) {
+		const char *a, *lb, *rb, *eol;
+
+		a = strstr(use_message_buffer, "\nauthor ");
+		if (!a)
+			die("invalid commit: %s\n", use_message);
+
+		lb = strstr(a + 8, " <");
+		rb = strstr(a + 8, "> ");
+		eol = strchr(a + 8, '\n');
+		if (!lb || !rb || !eol)
+			die("invalid commit: %s\n", use_message);
+
+		name = xstrndup(a + 8, lb - (a + 8));
+		email = xstrndup(lb + 2, rb - (lb + 2));
+		date = xstrndup(rb + 2, eol - (rb + 2));
+	}
+
+	if (force_author) {
+		const char *lb = strstr(force_author, " <");
+		const char *rb = strchr(force_author, '>');
+
+		if (!lb || !rb)
+			die("malformed --author parameter\n");
+		name = xstrndup(force_author, lb - force_author);
+		email = xstrndup(lb + 2, rb - (lb + 2));
+	}
+
+	strbuf_addf(sb, "author %s\n", fmt_ident(name, email, date, 1));
+}
+
+static int parse_and_validate_options(int argc, const char *argv[])
+{
+	int f = 0;
+
+	argc = parse_options(argc, argv, builtin_commit_options,
+			     builtin_commit_usage, 0);
+
+	if (logfile || message || use_message)
+		no_edit = 1;
+	if (edit_flag)
+		no_edit = 0;
+
+	if (get_sha1("HEAD", head_sha1))
+		initial_commit = 1;
+
+	if (!get_sha1("MERGE_HEAD", merge_head_sha1))
+		in_merge = 1;
+
+	/* Sanity check options */
+	if (amend && initial_commit)
+		die("You have nothing to amend.");
+	if (amend && in_merge)
+		die("You are in the middle of a merger -- cannot amend.");
+
+	if (use_message)
+		f++;
+	if (edit_message)
+		f++;
+	if (logfile)
+		f++;
+	if (f > 1)
+		die("Only one of -c/-C/-F can be used.");
+	if (message && f > 0)
+		die("Option -m cannot be combined with -c/-C/-F.");
+	if (edit_message)
+		use_message = edit_message;
+	if (amend)
+		use_message = "HEAD";
+	if (use_message) {
+		unsigned char sha1[20];
+		static char utf8[] = "UTF-8";
+		const char *out_enc;
+		char *enc, *end;
+		struct commit *commit;
+
+		if (get_sha1(use_message, sha1))
+			die("could not lookup commit %s", use_message);
+		commit = lookup_commit(sha1);
+		if (!commit || parse_commit(commit))
+			die("could not parse commit %s", use_message);
+
+		enc = strstr(commit->buffer, "\nencoding");
+		if (enc) {
+			end = strchr(enc + 10, '\n');
+			enc = xstrndup(enc + 10, end - (enc + 10));
+		} else {
+			enc = utf8;
+		}
+		out_enc = git_commit_encoding ? git_commit_encoding : utf8;
+
+		if (strcmp(out_enc, enc))
+			use_message_buffer =
+				reencode_string(commit->buffer, out_enc, enc);
+
+		/*
+		 * If we failed to reencode the buffer, just copy it
+		 * byte for byte so the user can try to fix it up.
+		 * This also handles the case where input and output
+		 * encodings are identical.
+		 */
+		if (use_message_buffer == NULL)
+			use_message_buffer = xstrdup(commit->buffer);
+		if (enc != utf8)
+			free(enc);
+	}
+
+	if (!!also + !!only + !!all + !!interactive > 1)
+		die("Only one of --include/--only/--all/--interactive can be used.");
+	if (argc == 0 && (also || (only && !amend)))
+		die("No paths with --include/--only does not make sense.");
+	if (argc == 0 && only && amend)
+		only_include_assumed = "Clever... amending the last one with dirty index.";
+	if (argc > 0 && !also && !only) {
+		only_include_assumed = "Explicit paths specified without -i nor -o; assuming --only paths...";
+		also = 0;
+	}
+
+	if (all && argc > 0)
+		die("Paths with -a does not make sense.");
+	else if (interactive && argc > 0)
+		die("Paths with --interactive does not make sense.");
+
+	return argc;
+}
+
+int cmd_status(int argc, const char **argv, const char *prefix)
+{
+	const char *index_file;
+	int commitable;
+
+	git_config(git_status_config);
+
+	argc = parse_and_validate_options(argc, argv);
+
+	index_file = prepare_index(argv, prefix);
+
+	commitable = run_status(stdout, index_file);
+
+	rollback_lock_file(&lock_file);
+
+	return commitable ? 0 : 1;
+}
+
+static int run_hook(const char *index_file, const char *name, const char *arg)
+{
+	struct child_process hook;
+	const char *argv[3], *env[2];
+	char index[PATH_MAX];
+
+	argv[0] = git_path("hooks/%s", name);
+	argv[1] = arg;
+	argv[2] = NULL;
+	snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
+	env[0] = index;
+	env[1] = NULL;
+
+	if (access(argv[0], X_OK) < 0)
+		return 0;
+
+	memset(&hook, 0, sizeof(hook));
+	hook.argv = argv;
+	hook.no_stdin = 1;
+	hook.stdout_to_stderr = 1;
+	hook.env = env;
+
+	return run_command(&hook);
+}
+
+static void print_summary(const char *prefix, const unsigned char *sha1)
+{
+	struct rev_info rev;
+	struct commit *commit;
+
+	commit = lookup_commit(sha1);
+	if (!commit)
+		die("couldn't look up newly created commit\n");
+	if (!commit || parse_commit(commit))
+		die("could not parse newly created commit");
+
+	init_revisions(&rev, prefix);
+	setup_revisions(0, NULL, &rev, NULL);
+
+	rev.abbrev = 0;
+	rev.diff = 1;
+	rev.diffopt.output_format =
+		DIFF_FORMAT_SHORTSTAT | DIFF_FORMAT_SUMMARY;
+
+	rev.verbose_header = 1;
+	rev.show_root_diff = 1;
+	rev.commit_format = get_commit_format("format:%h: %s");
+	rev.always_show_header = 1;
+
+	printf("Created %scommit ", initial_commit ? "initial " : "");
+
+	log_tree_commit(&rev, commit);
+}
+
+int git_commit_config(const char *k, const char *v)
+{
+	if (!strcmp(k, "commit.template")) {
+		template_file = xstrdup(v);
+		return 0;
+	}
+
+	return git_status_config(k, v);
+}
+
+static const char commit_utf8_warn[] =
+"Warning: commit message does not conform to UTF-8.\n"
+"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(int argc, const char **argv, const char *prefix)
+{
+	int header_len, parent_count = 0;
+	struct strbuf sb;
+	const char *index_file, *reflog_msg;
+	char *nl, *header_line;
+	unsigned char commit_sha1[20];
+	struct ref_lock *ref_lock;
+
+	git_config(git_commit_config);
+
+	argc = parse_and_validate_options(argc, argv);
+
+	index_file = prepare_index(argv, prefix);
+
+	if (!no_verify && run_hook(index_file, "pre-commit", NULL))
+		exit(1);
+
+	if (!prepare_log_message(index_file) && !in_merge) {
+		run_status(stdout, index_file);
+		unlink(commit_editmsg);
+		return 1;
+	}
+
+	strbuf_init(&sb, 0);
+
+	/* Start building up the commit header */
+	read_cache_from(index_file);
+	active_cache_tree = cache_tree();
+	if (cache_tree_update(active_cache_tree,
+			      active_cache, active_nr, 0, 0) < 0)
+		die("Error building trees");
+	strbuf_addf(&sb, "tree %s\n",
+		    sha1_to_hex(active_cache_tree->sha1));
+
+	/* Determine parents */
+	if (initial_commit) {
+		reflog_msg = "commit (initial)";
+		parent_count = 0;
+	} else if (amend) {
+		struct commit_list *c;
+		struct commit *commit;
+
+		reflog_msg = "commit (amend)";
+		commit = lookup_commit(head_sha1);
+		if (!commit || parse_commit(commit))
+			die("could not parse HEAD commit");
+
+		for (c = commit->parents; c; c = c->next)
+			strbuf_addf(&sb, "parent %s\n",
+				      sha1_to_hex(c->item->object.sha1));
+	} else if (in_merge) {
+		struct strbuf m;
+		FILE *fp;
+
+		reflog_msg = "commit (merge)";
+		strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
+		strbuf_init(&m, 0);
+		fp = fopen(git_path("MERGE_HEAD"), "r");
+		if (fp == NULL)
+			die("could not open %s for reading: %s",
+			    git_path("MERGE_HEAD"), strerror(errno));
+		while (strbuf_getline(&m, fp, '\n') != EOF)
+			strbuf_addf(&sb, "parent %s\n", m.buf);
+		fclose(fp);
+		strbuf_release(&m);
+	} else {
+		reflog_msg = "commit";
+		strbuf_addf(&sb, "parent %s\n", sha1_to_hex(head_sha1));
+	}
+
+	determine_author_info(&sb);
+	strbuf_addf(&sb, "committer %s\n", git_committer_info(1));
+	if (!is_encoding_utf8(git_commit_encoding))
+		strbuf_addf(&sb, "encoding %s\n", git_commit_encoding);
+	strbuf_addch(&sb, '\n');
+
+	/* Get the commit message and validate it */
+	header_len = sb.len;
+	if (!no_edit) {
+		fprintf(stderr, "launching editor, log %s\n", logfile);
+		launch_editor(git_path(commit_editmsg), &sb);
+	} else if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0)
+		die("could not read commit message\n");
+	if (run_hook(index_file, "commit-msg", commit_editmsg))
+		exit(1);
+	stripspace(&sb, 1);
+	if (sb.len < header_len ||
+	    message_is_empty(&sb, header_len))
+		die("* no commit message?  aborting commit.");
+	strbuf_addch(&sb, '\0');
+	if (is_encoding_utf8(git_commit_encoding) && !is_utf8(sb.buf))
+		fprintf(stderr, commit_utf8_warn);
+
+	if (write_sha1_file(sb.buf, sb.len - 1, commit_type, commit_sha1))
+		die("failed to write commit object");
+
+	ref_lock = lock_any_ref_for_update("HEAD",
+					   initial_commit ? NULL : head_sha1,
+					   0);
+
+	nl = strchr(sb.buf + header_len, '\n');
+	header_line = xstrndup(sb.buf + header_len,
+			       nl - (sb.buf + header_len));
+	strbuf_release(&sb);
+	strbuf_addf(&sb, "%s: %s\n", reflog_msg, header_line);
+	strbuf_addch(&sb, '\0');
+	free(header_line);
+
+	if (!ref_lock)
+		die("cannot lock HEAD ref");
+	if (write_ref_sha1(ref_lock, commit_sha1, sb.buf) < 0)
+		die("cannot update HEAD ref");
+
+	unlink(git_path("MERGE_HEAD"));
+	unlink(git_path("MERGE_MSG"));
+
+	if (lock_file.filename[0] && commit_locked_index(&lock_file))
+		die("failed to write new index");
+
+	rerere();
+
+	run_hook(index_file, "post-commit", NULL);
+
+	if (!quiet)
+		print_summary(prefix, commit_sha1);
+
+	return 0;
+}