Merge three separate "fetch refs" functions

It really just boils down to one "get_remote_heads()" function, and a
common "struct ref" structure definition.

cache.h

@@ -285,10 +285,18 @@ struct pack_entry {
 	struct packed_git *p;
 };
 
+struct ref {
+	struct ref *next;
+	unsigned char old_sha1[20];
+	unsigned char new_sha1[20];
+	char name[0];
+};
+
 extern int git_connect(int fd[2], char *url, const char *prog);
 extern int finish_connect(pid_t pid);
 extern int path_match(const char *path, int nr, char **match);
 extern int get_ack(int fd, unsigned char *result_sha1);
+extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match);
 
 extern void prepare_packed_git(void);
 extern int use_packed_git(struct packed_git *);

clone-pack.c

@@ -7,50 +7,12 @@ static int quiet;
 static const char clone_pack_usage[] = "git-clone-pack [-q] [--exec=<git-upload-pack>] [<host>:]<directory> [<heads>]*";
 static const char *exec = "git-upload-pack";
 
-struct ref {
-	struct ref *next;
-	unsigned char sha1[20];
-	char name[0];
-};
-
-static struct ref *get_remote_refs(int fd, int nr_match, char **match)
-{
-	struct ref *ref_list = NULL, **next_ref = &ref_list;
-
-	for (;;) {
-		static char line[1000];
-		unsigned char sha1[20];
-		struct ref *ref;
-		char *refname;
-		int len;
-
-		len = packet_read_line(fd, line, sizeof(line));
-		if (!len)
-			break;
-		if (line[len-1] == '\n')
-			line[--len] = 0;
-		if (len < 42 || get_sha1_hex(line, sha1))
-			die("git-clone-pack: protocol error - expected ref descriptor, got '%s'", line);
-		refname = line+41;
-		len = len-40;
-		if (nr_match && !path_match(refname, nr_match, match))
-			continue;
-		ref = xmalloc(sizeof(struct ref) + len);
-		ref->next = NULL;
-		memcpy(ref->sha1, sha1, 20);
-		memcpy(ref->name, refname, len);
-		*next_ref = ref;
-		next_ref = &ref->next;
-	}
-	return ref_list;
-}
-
 static void clone_handshake(int fd[2], struct ref *ref)
 {
 	unsigned char sha1[20];
 
 	while (ref) {
-		packet_write(fd[1], "want %s\n", sha1_to_hex(ref->sha1));
+		packet_write(fd[1], "want %s\n", sha1_to_hex(ref->old_sha1));
 		ref = ref->next;
 	}
 	packet_flush(fd[1]);
@@ -77,7 +39,7 @@ static void write_one_ref(struct ref *ref)
 	fd = open(path, O_CREAT | O_EXCL | O_WRONLY, 0666);
 	if (fd < 0)
 		die("unable to create ref %s", ref->name);
-	hex = sha1_to_hex(ref->sha1);
+	hex = sha1_to_hex(ref->old_sha1);
 	hex[40] = '\n';
 	if (write(fd, hex, 41) != 41)
 		die("unable to write ref %s", ref->name);
@@ -98,7 +60,7 @@ static void write_refs(struct ref *ref)
 	while (ref) {
 		if (is_master(ref))
 			master_ref = ref;
-		if (head && !memcmp(ref->sha1, head->sha1, 20)) {
+		if (head && !memcmp(ref->old_sha1, head->old_sha1, 20)) {
 			if (!head_ptr || ref == master_ref)
 				head_ptr = ref;
 		}
@@ -142,7 +104,7 @@ static int clone_pack(int fd[2], int nr_match, char **match)
 	int status;
 	pid_t pid;
 
-	refs = get_remote_refs(fd[0], nr_match, match);
+	get_remote_heads(fd[0], &refs, nr_match, match);
 	if (!refs) {
 		packet_flush(fd[1]);
 		die("no matching remote head");

connect.c

@@ -7,6 +7,41 @@
 #include <arpa/inet.h>
 #include <netdb.h>
 
+/*
+ * Read all the refs from the other end
+ */
+struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match)
+{
+	*list = NULL;
+	for (;;) {
+		struct ref *ref;
+		unsigned char old_sha1[20];
+		static char buffer[1000];
+		char *name;
+		int len;
+
+		len = packet_read_line(in, buffer, sizeof(buffer));
+		if (!len)
+			break;
+		if (buffer[len-1] == '\n')
+			buffer[--len] = 0;
+
+		if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
+			die("protocol error: expected sha/ref, got '%s'", buffer);
+		name = buffer + 41;
+		if (nr_match && !path_match(name, nr_match, match))
+			continue;
+		ref = xmalloc(sizeof(*ref) + len - 40);
+		memcpy(ref->old_sha1, old_sha1, 20);
+		memset(ref->new_sha1, 0, 20);
+		memcpy(ref->name, buffer + 41, len - 40);
+		ref->next = NULL;
+		*list = ref;
+		list = &ref->next;
+	}
+	return list;
+}
+
 int get_ack(int fd, unsigned char *result_sha1)
 {
 	static char line[1000];

fetch-pack.c

@@ -53,44 +53,28 @@ static int find_common(int fd[2], unsigned char *result_sha1, unsigned char *rem
 	return retval;
 }
 
-static int get_remote_heads(int fd, int nr_match, char **match, unsigned char *result)
-{
-	int count = 0;
-
-	for (;;) {
-		static char line[1000];
-		unsigned char sha1[20];
-		char *refname;
-		int len;
-
-		len = packet_read_line(fd, line, sizeof(line));
-		if (!len)
-			break;
-		if (line[len-1] == '\n')
-			line[--len] = 0;
-		if (len < 42 || get_sha1_hex(line, sha1))
-			die("git-fetch-pack: protocol error - expected ref descriptor, got '%s'", line);
-		refname = line+41;
-		if (nr_match && !path_match(refname, nr_match, match))
-			continue;
-		count++;
-		memcpy(result, sha1, 20);
-	}
-	return count;
-}
-
+/*
+ * Eventually we'll want to be able to fetch multiple heads.
+ *
+ * Right now we'll just require a single match.
+ */
 static int fetch_pack(int fd[2], int nr_match, char **match)
 {
-	unsigned char sha1[20], remote[20];
-	int heads, status;
+	struct ref *ref;
+	unsigned char sha1[20];
+	int status;
 	pid_t pid;
 
-	heads = get_remote_heads(fd[0], nr_match, match, remote);
-	if (heads != 1) {
+	get_remote_heads(fd[0], &ref, nr_match, match);
+	if (!ref) {
 		packet_flush(fd[1]);
-		die(heads ? "multiple remote heads" : "no matching remote head");
+		die("no matching remote head");
 	}
-	if (find_common(fd, sha1, remote) < 0)
+	if (ref->next) {
+		packet_flush(fd[1]);
+		die("multiple remote heads");
+	}
+	if (find_common(fd, sha1, ref->old_sha1) < 0)
 		die("git-fetch-pack: no common commits");
 	pid = fork();
 	if (pid < 0)
@@ -113,7 +97,7 @@ static int fetch_pack(int fd[2], int nr_match, char **match)
 		int code = WEXITSTATUS(status);
 		if (code)
 			die("git-unpack-objects died with error code %d", code);
-		puts(sha1_to_hex(remote));
+		puts(sha1_to_hex(ref->old_sha1));
 		return 0;
 	}
 	if (WIFSIGNALED(status)) {

send-pack.c

@@ -7,13 +7,6 @@ static const char send_pack_usage[] =
 static const char *exec = "git-receive-pack";
 static int send_all = 0;
 
-struct ref {
-	struct ref *next;
-	unsigned char old_sha1[20];
-	unsigned char new_sha1[20];
-	char name[0];
-};
-
 static int is_zero_sha1(const unsigned char *sha1)
 {
 	int i;
@@ -170,36 +163,12 @@ static int try_to_match(const char *refname, const unsigned char *sha1)
 
 static int send_pack(int in, int out, int nr_match, char **match)
 {
-	struct ref *ref_list = NULL, **last_ref = &ref_list;
+	struct ref *ref_list, **last_ref;
 	struct ref *ref;
 	int new_refs;
 
-	/*
-	 * Read all the refs from the other end
-	 */
-	for (;;) {
-		unsigned char old_sha1[20];
-		static char buffer[1000];
-		char *name;
-		int len;
-
-		len = packet_read_line(in, buffer, sizeof(buffer));
-		if (!len)
-			break;
-		if (buffer[len-1] == '\n')
-			buffer[--len] = 0;
-
-		if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
-			die("protocol error: expected sha/ref, got '%s'", buffer);
-		name = buffer + 41;
-		ref = xmalloc(sizeof(*ref) + len - 40);
-		memcpy(ref->old_sha1, old_sha1, 20);
-		memset(ref->new_sha1, 0, 20);
-		memcpy(ref->name, buffer + 41, len - 40);
-		ref->next = NULL;
-		*last_ref = ref;
-		last_ref = &ref->next;
-	}
+	/* First we get all heads, whether matching or not.. */
+	last_ref = get_remote_heads(in, &ref_list, 0, NULL);
 
 	/*
 	 * Go through the refs, see if we want to update