Commit first cut at "git-fetch-pack"

It's meant to be used by "git fetch" for the local and ssh case.

It doesn't actually do the fetching now, but it does discover the common
commit point.

1 files changed, 86 insertions, 0 deletions

diff --git a/upload-pack.c b/upload-pack.c
new file mode 100644
index 0000000000..18b8e1a6ca
--- /dev/null
+++ b/upload-pack.c
@@ -0,0 +1,86 @@
+#include "cache.h"
+#include "refs.h"
+#include "pkt-line.h"
+
+static const char upload_pack_usage[] = "git-upload-pack <dir>";
+
+static int got_sha1(char *hex, unsigned char *sha1)
+{
+	if (get_sha1_hex(hex, sha1))
+		die("git-upload-pack: expected SHA1 object, got '%s'", hex);
+	return has_sha1_file(sha1);
+}
+
+static int get_common_commits(void)
+{
+	static char line[1000];
+	unsigned char sha1[20];
+	int len;
+
+	for(;;) {
+		len = packet_read_line(0, line, sizeof(line));
+
+		if (!len) {
+			packet_write(1, "NAK\n");
+			continue;
+		}
+		if (line[len-1] == '\n')
+			line[--len] = 0;
+		if (!strncmp(line, "have ", 5)) {
+			if (got_sha1(line+5, sha1)) {
+				packet_write(1, "ACK %s\n", sha1_to_hex(sha1));
+				break;
+			}
+			continue;
+		}
+		if (!strcmp(line, "done")) {
+			packet_write(1, "NAK\n");
+			return -1;
+		}
+		die("git-upload-pack: expected SHA1 list, got '%s'", line);
+	}
+
+	for (;;) {
+		len = packet_read_line(0, line, sizeof(line));
+		if (!len)
+			break;
+		if (!strncmp(line, "have ", 5)) {
+			got_sha1(line+5, sha1);
+			continue;
+		}
+		if (!strcmp(line, "done"))
+			break;
+		die("git-upload-pack: expected SHA1 list, got '%s'", line);
+	}
+	return 0;
+}
+
+static int send_ref(const char *refname, const unsigned char *sha1)
+{
+	packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
+	return 0;
+}
+
+static int upload_pack(void)
+{
+	for_each_ref(send_ref);
+	packet_flush(1);
+	get_common_commits();
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	const char *dir;
+	if (argc != 2)
+		usage(upload_pack_usage);
+	dir = argv[1];
+	if (chdir(dir))
+		die("git-upload-pack unable to chdir to %s", dir);
+	chdir(".git");
+	if (access("objects", X_OK) || access("refs", X_OK))
+		die("git-upload-pack: %s doesn't seem to be a git archive", dir);
+	setenv("GIT_DIR", ".", 1);
+	upload_pack();
+	return 0;
+}