1 files changed, 140 insertions, 0 deletions
diff --git a/builtin-commit-tree.c b/builtin-commit-tree.c
new file mode 100644
index 0000000000..ec082bf754
--- /dev/null
+++ b/builtin-commit-tree.c
@@ -0,0 +1,140 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+#include "commit.h"
+#include "tree.h"
+#include "builtin.h"
+
+#define BLOCKING (1ul << 14)
+
+/*
+ * FIXME! Share the code with "write-tree.c"
+ */
+static void init_buffer(char **bufp, unsigned int *sizep)
+{
+	char *buf = xmalloc(BLOCKING);
+	*sizep = 0;
+	*bufp = buf;
+}
+
+static void add_buffer(char **bufp, unsigned int *sizep, const char *fmt, ...)
+{
+	char one_line[2048];
+	va_list args;
+	int len;
+	unsigned long alloc, size, newsize;
+	char *buf;
+
+	va_start(args, fmt);
+	len = vsnprintf(one_line, sizeof(one_line), fmt, args);
+	va_end(args);
+	size = *sizep;
+	newsize = size + len;
+	alloc = (size + 32767) & ~32767;
+	buf = *bufp;
+	if (newsize > alloc) {
+		alloc = (newsize + 32767) & ~32767;
+		buf = xrealloc(buf, alloc);
+		*bufp = buf;
+	}
+	*sizep = newsize;
+	memcpy(buf + size, one_line, len);
+}
+
+static void check_valid(unsigned char *sha1, const char *expect)
+{
+	char type[20];
+
+	if (sha1_object_info(sha1, type, NULL))
+		die("%s is not a valid object", sha1_to_hex(sha1));
+	if (expect && strcmp(type, expect))
+		die("%s is not a valid '%s' object", sha1_to_hex(sha1),
+		    expect);
+}
+
+/*
+ * Having more than two parents is not strange at all, and this is
+ * how multi-way merges are represented.
+ */
+#define MAXPARENT (16)
+static unsigned char parent_sha1[MAXPARENT][20];
+
+static const char commit_tree_usage[] = "git-commit-tree <sha1> [-p <sha1>]* < changelog";
+
+static int new_parent(int idx)
+{
+	int i;
+	unsigned char *sha1 = parent_sha1[idx];
+	for (i = 0; i < idx; i++) {
+		if (!memcmp(parent_sha1[i], sha1, 20)) {
+			error("duplicate parent %s ignored", sha1_to_hex(sha1));
+			return 0;
+		}
+	}
+	return 1;
+}
+
+int cmd_commit_tree(int argc, const char **argv, char **envp)
+{
+	int i;
+	int parents = 0;
+	unsigned char tree_sha1[20];
+	unsigned char commit_sha1[20];
+	char comment[1000];
+	char *buffer;
+	unsigned int size;
+
+	setup_ident();
+	setup_git_directory();
+
+	git_config(git_default_config);
+
+	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, tree_type);
+	for (i = 2; i < argc; i += 2) {
+		const char *a, *b;
+		a = argv[i]; b = argv[i+1];
+		if (!b || strcmp(a, "-p"))
+			usage(commit_tree_usage);
+		if (get_sha1(b, parent_sha1[parents]))
+			die("Not a valid object name %s", b);
+		check_valid(parent_sha1[parents], commit_type);
+		if (new_parent(parents))
+			parents++;
+	}
+	if (!parents)
+		fprintf(stderr, "Committing initial tree %s\n", argv[1]);
+
+	init_buffer(&buffer, &size);
+	add_buffer(&buffer, &size, "tree %s\n", sha1_to_hex(tree_sha1));
+
+	/*
+	 * NOTE! This ordering means that the same exact tree merged with a
+	 * different order of parents will be a _different_ changeset even
+	 * if everything else stays the same.
+	 */
+	for (i = 0; i < parents; i++)
+		add_buffer(&buffer, &size, "parent %s\n", sha1_to_hex(parent_sha1[i]));
+
+	/* Person/date information */
+	add_buffer(&buffer, &size, "author %s\n", git_author_info(1));
+	add_buffer(&buffer, &size, "committer %s\n\n", git_committer_info(1));
+
+	/* And add the comment */
+	while (fgets(comment, sizeof(comment), stdin) != NULL)
+		add_buffer(&buffer, &size, "%s", comment);
+
+	if (!write_sha1_file(buffer, size, commit_type, commit_sha1)) {
+		printf("%s\n", sha1_to_hex(commit_sha1));
+		return 0;
+	}
+	else
+		return 1;
+}