diff --git a/Makefile b/Makefile
index 4ce0132a2a..9ababab129 100644
--- a/Makefile
+++ b/Makefile
@@ -244,7 +244,7 @@ XDIFF_LIB=xdiff/lib.a
 
 LIB_H = \
 	archive.h blob.h cache.h commit.h csum-file.h delta.h \
-	diff.h object.h pack.h pkt-line.h quote.h refs.h list-objects.h \
+	diff.h object.h pack.h pkt-line.h quote.h refs.h list-objects.h sideband.h \
 	run-command.h strbuf.h tag.h tree.h git-compat-util.h revision.h \
 	tree-walk.h log-tree.h dir.h path-list.h unpack-trees.h builtin.h
 
@@ -256,7 +256,7 @@ DIFF_OBJS = \
 LIB_OBJS = \
 	blob.o commit.o connect.o csum-file.o cache-tree.o base85.o \
 	date.o diff-delta.o entry.o exec_cmd.o ident.o lockfile.o \
-	object.o pack-check.o patch-delta.o path.o pkt-line.o \
+	object.o pack-check.o patch-delta.o path.o pkt-line.o sideband.o \
 	quote.o read-cache.o refs.o run-command.o dir.o object-refs.o \
 	server-info.o setup.o sha1_file.o sha1_name.o strbuf.o \
 	tag.o tree.o usage.o config.o environment.o ctype.o copy.o \
diff --git a/archive.h b/archive.h
index d8cca735d2..16dcdb875c 100644
--- a/archive.h
+++ b/archive.h
@@ -10,6 +10,7 @@ struct archiver_args {
 	const unsigned char *commit_sha1;
 	time_t time;
 	const char **pathspec;
+	unsigned int verbose : 1;
 	void *extra;
 };
 
@@ -19,7 +20,6 @@ typedef void *(*parse_extra_args_fn_t)(int argc, const char **argv);
 
 struct archiver {
 	const char *name;
-	const char *remote;
 	struct archiver_args args;
 	write_archive_fn_t write_archive;
 	parse_extra_args_fn_t parse_extra;
diff --git a/builtin-archive.c b/builtin-archive.c
index b944737550..cb883dfe5f 100644
--- a/builtin-archive.c
+++ b/builtin-archive.c
@@ -10,9 +10,10 @@
 #include "tree-walk.h"
 #include "exec_cmd.h"
 #include "pkt-line.h"
+#include "sideband.h"
 
 static const char archive_usage[] = \
-"git-archive --format=<fmt> [--prefix=<prefix>/] [<extra>] <tree-ish> [path...]";
+"git-archive --format=<fmt> [--prefix=<prefix>/] [--verbose] [<extra>] <tree-ish> [path...]";
 
 struct archiver archivers[] = {
 	{
@@ -26,22 +27,33 @@ struct archiver archivers[] = {
 	},
 };
 
-static int run_remote_archiver(struct archiver *ar, int argc,
+static int run_remote_archiver(const char *remote, int argc,
 			       const char **argv)
 {
-	char *url, buf[1024];
+	char *url, buf[LARGE_PACKET_MAX];
 	int fd[2], i, len, rv;
 	pid_t pid;
+	const char *exec = "git-upload-archive";
+	int exec_at = 0;
 
-	sprintf(buf, "git-upload-archive");
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		if (!strncmp("--exec=", arg, 7)) {
+			if (exec_at)
+				die("multiple --exec specified");
+			exec = arg + 7;
+			exec_at = i;
+			break;
+		}
+	}
 
-	url = xstrdup(ar->remote);
-	pid = git_connect(fd, url, buf);
+	url = xstrdup(remote);
+	pid = git_connect(fd, url, exec);
 	if (pid < 0)
 		return pid;
 
 	for (i = 1; i < argc; i++) {
-		if (!strncmp(argv[i], "--remote=", 9))
+		if (i == exec_at)
 			continue;
 		packet_write(fd[1], "argument %s\n", argv[i]);
 	}
@@ -63,8 +75,7 @@ static int run_remote_archiver(struct archiver *ar, int argc,
 		die("git-archive: expected a flush");
 
 	/* Now, start reading from fd[0] and spit it out to stdout */
-	rv = copy_fd(fd[0], 1);
-
+	rv = recv_sideband("archive", fd[0], 1, 2, buf, sizeof(buf));
 	close(fd[0]);
 	rv |= finish_connect(pid);
 
@@ -150,16 +161,20 @@ int parse_archive_args(int argc, const char **argv, struct archiver *ar)
 	const char *extra_argv[MAX_EXTRA_ARGS];
 	int extra_argc = 0;
 	const char *format = NULL; /* might want to default to "tar" */
-	const char *remote = NULL;
 	const char *base = "";
-	int list = 0;
+	int verbose = 0;
 	int i;
 
 	for (i = 1; i < argc; i++) {
 		const char *arg = argv[i];
 
 		if (!strcmp(arg, "--list") || !strcmp(arg, "-l")) {
-			list = 1;
+			for (i = 0; i < ARRAY_SIZE(archivers); i++)
+				printf("%s\n", archivers[i].name);
+			exit(0);
+		}
+		if (!strcmp(arg, "--verbose") || !strcmp(arg, "-v")) {
+			verbose = 1;
 			continue;
 		}
 		if (!strncmp(arg, "--format=", 9)) {
@@ -170,10 +185,6 @@ int parse_archive_args(int argc, const char **argv, struct archiver *ar)
 			base = arg + 9;
 			continue;
 		}
-		if (!strncmp(arg, "--remote=", 9)) {
-			remote = arg + 9;
-			continue;
-		}
 		if (!strcmp(arg, "--")) {
 			i++;
 			break;
@@ -187,44 +198,70 @@ int parse_archive_args(int argc, const char **argv, struct archiver *ar)
 		break;
 	}
 
-	if (list) {
-		if (!remote) {
-			for (i = 0; i < ARRAY_SIZE(archivers); i++)
-				printf("%s\n", archivers[i].name);
-			exit(0);
-		}
-		die("--list and --remote are mutually exclusive");
-	}
-
-	if (argc - i < 1)
+	/* We need at least one parameter -- tree-ish */
+	if (argc - 1 < i)
 		usage(archive_usage);
 	if (!format)
 		die("You must specify an archive format");
 	if (init_archiver(format, ar) < 0)
 		die("Unknown archive format '%s'", format);
 
-	if (extra_argc && !remote) {
-		if (!ar->parse_extra) {
+	if (extra_argc) {
+		if (!ar->parse_extra)
 			die("%s", default_parse_extra(ar, extra_argv));
-		}
 		ar->args.extra = ar->parse_extra(extra_argc, extra_argv);
 	}
-	ar->remote = remote;
+	ar->args.verbose = verbose;
 	ar->args.base = base;
 
 	return i;
 }
 
+static const char *remote_request(int *ac, const char **av)
+{
+	int ix, iy, cnt = *ac;
+	int no_more_options = 0;
+	const char *remote = NULL;
+
+	for (ix = iy = 1; ix < cnt; ix++) {
+		const char *arg = av[ix];
+		if (!strcmp(arg, "--"))
+			no_more_options = 1;
+		if (!no_more_options) {
+			if (!strncmp(arg, "--remote=", 9)) {
+				if (remote)
+					die("Multiple --remote specified");
+				remote = arg + 9;
+				continue;
+			}
+			if (arg[0] != '-')
+				no_more_options = 1;
+		}
+		if (ix != iy)
+			av[iy] = arg;
+		iy++;
+	}
+	if (remote) {
+		av[--cnt] = NULL;
+		*ac = cnt;
+	}
+	return remote;
+}
+
 int cmd_archive(int argc, const char **argv, const char *prefix)
 {
 	struct archiver ar;
 	int tree_idx;
+	const char *remote = NULL;
 
+	remote = remote_request(&argc, argv);
+	if (remote)
+		return run_remote_archiver(remote, argc, argv);
+
+	setlinebuf(stderr);
+
+	memset(&ar, 0, sizeof(ar));
 	tree_idx = parse_archive_args(argc, argv, &ar);
-
-	if (ar.remote)
-		return run_remote_archiver(&ar, argc, argv);
-
 	if (prefix == NULL)
 		prefix = setup_git_directory();
 
diff --git a/builtin-tar-tree.c b/builtin-tar-tree.c
index c20eb0e364..f2679a8637 100644
--- a/builtin-tar-tree.c
+++ b/builtin-tar-tree.c
@@ -22,6 +22,7 @@ static unsigned long offset;
 
 static time_t archive_time;
 static int tar_umask;
+static int verbose;
 
 /* writes out the whole block, but only if it is full */
 static void write_if_needed(void)
@@ -169,6 +170,8 @@ static void write_entry(const unsigned char *sha1, struct strbuf *path,
 		mode = 0100666;
 		sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1));
 	} else {
+		if (verbose)
+			fprintf(stderr, "%.*s\n", path->len, path->buf);
 		if (S_ISDIR(mode)) {
 			*header.typeflag = TYPEFLAG_DIR;
 			mode = (mode | 0777) & ~tar_umask;
@@ -385,12 +388,13 @@ int write_tar_archive(struct archiver_args *args)
 	git_config(git_tar_config);
 
 	archive_time = args->time;
+	verbose = args->verbose;
 
 	if (args->commit_sha1)
 		write_global_extended_header(args->commit_sha1);
 
 	if (args->base && plen > 0 && args->base[plen - 1] == '/') {
-		char *base = strdup(args->base);
+		char *base = xstrdup(args->base);
 		int baselen = strlen(base);
 
 		while (baselen > 0 && base[baselen - 1] == '/')
diff --git a/builtin-upload-archive.c b/builtin-upload-archive.c
index 3bdb607e37..42cb9f8876 100644
--- a/builtin-upload-archive.c
+++ b/builtin-upload-archive.c
@@ -6,12 +6,18 @@
 #include "builtin.h"
 #include "archive.h"
 #include "pkt-line.h"
+#include "sideband.h"
+#include <sys/wait.h>
+#include <sys/poll.h>
 
 static const char upload_archive_usage[] =
 	"git-upload-archive <repo>";
 
+static const char deadchild[] =
+"git-upload-archive: archiver died with error";
 
-int cmd_upload_archive(int argc, const char **argv, const char *prefix)
+
+static int run_upload_archive(int argc, const char **argv, const char *prefix)
 {
 	struct archiver ar;
 	const char *sent_argv[MAX_ARGS];
@@ -64,9 +70,89 @@ int cmd_upload_archive(int argc, const char **argv, const char *prefix)
 	parse_treeish_arg(sent_argv + treeish_idx, &ar.args, prefix);
 	parse_pathspec_arg(sent_argv + treeish_idx + 1, &ar.args);
 
-	packet_write(1, "ACK\n");
-	packet_flush(1);
-
 	return ar.write_archive(&ar.args);
 }
 
+int cmd_upload_archive(int argc, const char **argv, const char *prefix)
+{
+	pid_t writer;
+	int fd1[2], fd2[2];
+	/*
+	 * Set up sideband subprocess.
+	 *
+	 * We (parent) monitor and read from child, sending its fd#1 and fd#2
+	 * multiplexed out to our fd#1.  If the child dies, we tell the other
+	 * end over channel #3.
+	 */
+	if (pipe(fd1) < 0 || pipe(fd2) < 0) {
+		int err = errno;
+		packet_write(1, "NACK pipe failed on the remote side\n");
+		die("upload-archive: %s", strerror(err));
+	}
+	writer = fork();
+	if (writer < 0) {
+		int err = errno;
+		packet_write(1, "NACK fork failed on the remote side\n");
+		die("upload-archive: %s", strerror(err));
+	}
+	if (!writer) {
+		/* child - connect fd#1 and fd#2 to the pipe */
+		dup2(fd1[1], 1);
+		dup2(fd2[1], 2);
+		close(fd1[1]); close(fd2[1]);
+		close(fd1[0]); close(fd2[0]); /* we do not read from pipe */
+
+		exit(run_upload_archive(argc, argv, prefix));
+	}
+
+	/* parent - read from child, multiplex and send out to fd#1 */
+	close(fd1[1]); close(fd2[1]); /* we do not write to pipe */
+	packet_write(1, "ACK\n");
+	packet_flush(1);
+
+	while (1) {
+		struct pollfd pfd[2];
+		char buf[16384];
+		ssize_t sz;
+		pid_t pid;
+		int status;
+
+		pfd[0].fd = fd1[0];
+		pfd[0].events = POLLIN;
+		pfd[1].fd = fd2[0];
+		pfd[1].events = POLLIN;
+		if (poll(pfd, 2, -1) < 0) {
+			if (errno != EINTR) {
+				error("poll failed resuming: %s",
+				      strerror(errno));
+				sleep(1);
+			}
+			continue;
+		}
+		if (pfd[0].revents & (POLLIN|POLLHUP)) {
+			/* Data stream ready */
+			sz = read(pfd[0].fd, buf, sizeof(buf));
+			send_sideband(1, 1, buf, sz, LARGE_PACKET_MAX);
+		}
+		if (pfd[1].revents & (POLLIN|POLLHUP)) {
+			/* Status stream ready */
+			sz = read(pfd[1].fd, buf, sizeof(buf));
+			send_sideband(1, 2, buf, sz, LARGE_PACKET_MAX);
+		}
+
+		if (((pfd[0].revents | pfd[1].revents) & POLLHUP) == 0)
+			continue;
+		/* did it die? */
+		pid = waitpid(writer, &status, WNOHANG);
+		if (!pid) {
+			fprintf(stderr, "Hmph, HUP?\n");
+			continue;
+		}
+		if (!WIFEXITED(status) || WEXITSTATUS(status) > 0)
+			send_sideband(1, 3, deadchild, strlen(deadchild),
+				      LARGE_PACKET_MAX);
+		packet_flush(1);
+		break;
+	}
+	return 0;
+}
diff --git a/builtin-zip-tree.c b/builtin-zip-tree.c
index 4e796338af..52d4b7a17e 100644
--- a/builtin-zip-tree.c
+++ b/builtin-zip-tree.c
@@ -13,6 +13,7 @@
 static const char zip_tree_usage[] =
 "git-zip-tree [-0|...|-9] <tree-ish> [ <base> ]";
 
+static int verbose;
 static int zip_date;
 static int zip_time;
 
@@ -164,6 +165,8 @@ static int write_zip_entry(const unsigned char *sha1,
 	crc = crc32(0, Z_NULL, 0);
 
 	path = construct_path(base, baselen, filename, S_ISDIR(mode), &pathlen);
+	if (verbose)
+		fprintf(stderr, "%s\n", path);
 	if (pathlen > 0xffff) {
 		error("path too long (%d chars, SHA1: %s): %s", pathlen,
 		      sha1_to_hex(sha1), path);
@@ -361,9 +364,10 @@ int write_zip_archive(struct archiver_args *args)
 
 	zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 	zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
+	verbose = args->verbose;
 
 	if (args->base && plen > 0 && args->base[plen - 1] == '/') {
-		char *base = strdup(args->base);
+		char *base = xstrdup(args->base);
 		int baselen = strlen(base);
 
 		while (baselen > 0 && base[baselen - 1] == '/')
diff --git a/fetch-clone.c b/fetch-clone.c
index c5cf4776fa..b632ca0438 100644
--- a/fetch-clone.c
+++ b/fetch-clone.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "exec_cmd.h"
 #include "pkt-line.h"
+#include "sideband.h"
 #include <sys/wait.h>
 #include <sys/time.h>
 
@@ -114,36 +115,13 @@ static pid_t setup_sideband(int sideband, const char *me, int fd[2], int xd[2])
 		die("%s: unable to fork off sideband demultiplexer", me);
 	if (!side_pid) {
 		/* subprocess */
+		char buf[LARGE_PACKET_MAX];
+
 		close(fd[0]);
 		if (xd[0] != xd[1])
 			close(xd[1]);
-		while (1) {
-			char buf[1024];
-			int len = packet_read_line(xd[0], buf, sizeof(buf));
-			if (len == 0)
-				break;
-			if (len < 1)
-				die("%s: protocol error: no band designator",
-				    me);
-			len--;
-			switch (buf[0] & 0xFF) {
-			case 3:
-				safe_write(2, "remote: ", 8);
-				safe_write(2, buf+1, len);
-				safe_write(2, "\n", 1);
-				exit(1);
-			case 2:
-				safe_write(2, "remote: ", 8);
-				safe_write(2, buf+1, len);
-				continue;
-			case 1:
-				safe_write(fd[1], buf+1, len);
-				continue;
-			default:
-				die("%s: protocol error: bad band #%d",
-				    me, (buf[0] & 0xFF));
-			}
-		}
+		if (recv_sideband(me, xd[0], fd[1], 2, buf, sizeof(buf)))
+			exit(1);
 		exit(0);
 	}
 	close(xd[0]);
diff --git a/fetch-pack.c b/fetch-pack.c
index 377feded1c..1b2d6ee20d 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -166,10 +166,11 @@ static int find_common(int fd[2], unsigned char *result_sha1,
 		}
 
 		if (!fetching)
-			packet_write(fd[1], "want %s%s%s%s\n",
+			packet_write(fd[1], "want %s%s%s%s%s\n",
 				     sha1_to_hex(remote),
 				     (multi_ack ? " multi_ack" : ""),
-				     (use_sideband ? " side-band" : ""),
+				     (use_sideband == 2 ? " side-band-64k" : ""),
+				     (use_sideband == 1 ? " side-band" : ""),
 				     (use_thin_pack ? " thin-pack" : ""));
 		else
 			packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
@@ -426,7 +427,12 @@ static int fetch_pack(int fd[2], int nr_match, char **match)
 			fprintf(stderr, "Server supports multi_ack\n");
 		multi_ack = 1;
 	}
-	if (server_supports("side-band")) {
+	if (server_supports("side-band-64k")) {
+		if (verbose)
+			fprintf(stderr, "Server supports side-band-64k\n");
+		use_sideband = 2;
+	}
+	else if (server_supports("side-band")) {
 		if (verbose)
 			fprintf(stderr, "Server supports side-band\n");
 		use_sideband = 1;
diff --git a/sha1_file.c b/sha1_file.c
index d5d048af67..b89edb9515 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -26,15 +26,43 @@ const unsigned char null_sha1[20];
 
 static unsigned int sha1_file_open_flag = O_NOATIME;
 
-static unsigned hexval(char c)
+static inline unsigned int hexval(unsigned int c)
 {
-	if (c >= '0' && c <= '9')
-		return c - '0';
-	if (c >= 'a' && c <= 'f')
-		return c - 'a' + 10;
-	if (c >= 'A' && c <= 'F')
-		return c - 'A' + 10;
-	return ~0;
+	static signed char val[256] = {
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 00-07 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 08-0f */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 10-17 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 18-1f */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 20-27 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 28-2f */
+		  0,  1,  2,  3,  4,  5,  6,  7,		/* 30-37 */
+		  8,  9, -1, -1, -1, -1, -1, -1,		/* 38-3f */
+		 -1, 10, 11, 12, 13, 14, 15, -1,		/* 40-47 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 48-4f */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 50-57 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 58-5f */
+		 -1, 10, 11, 12, 13, 14, 15, -1,		/* 60-67 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 68-67 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 70-77 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 78-7f */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 80-87 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 88-8f */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 90-97 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* 98-9f */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* a0-a7 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* a8-af */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* b0-b7 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* b8-bf */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* c0-c7 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* c8-cf */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* d0-d7 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* d8-df */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* e0-e7 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* e8-ef */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* f0-f7 */
+		 -1, -1, -1, -1, -1, -1, -1, -1,		/* f8-ff */
+	};
+	return val[c];
 }
 
 int get_sha1_hex(const char *hex, unsigned char *sha1)
diff --git a/sideband.c b/sideband.c
new file mode 100644
index 0000000000..1b14ff8892
--- /dev/null
+++ b/sideband.c
@@ -0,0 +1,74 @@
+#include "pkt-line.h"
+#include "sideband.h"
+
+/*
+ * Receive multiplexed output stream over git native protocol.
+ * in_stream is the input stream from the remote, which carries data
+ * in pkt_line format with band designator.  Demultiplex it into out
+ * and err and return error appropriately.  Band #1 carries the
+ * primary payload.  Things coming over band #2 is not necessarily
+ * error; they are usually informative message on the standard error
+ * stream, aka "verbose").  A message over band #3 is a signal that
+ * the remote died unexpectedly.  A flush() concludes the stream.
+ */
+int recv_sideband(const char *me, int in_stream, int out, int err, char *buf, int bufsz)
+{
+	while (1) {
+		int len = packet_read_line(in_stream, buf, bufsz);
+		if (len == 0)
+			break;
+		if (len < 1) {
+			len = sprintf(buf, "%s: protocol error: no band designator\n", me);
+			safe_write(err, buf, len);
+			return SIDEBAND_PROTOCOL_ERROR;
+		}
+		len--;
+		switch (buf[0] & 0xFF) {
+		case 3:
+			safe_write(err, "remote: ", 8);
+			safe_write(err, buf+1, len);
+			safe_write(err, "\n", 1);
+			return SIDEBAND_REMOTE_ERROR;
+		case 2:
+			safe_write(err, "remote: ", 8);
+			safe_write(err, buf+1, len);
+			continue;
+		case 1:
+			safe_write(out, buf+1, len);
+			continue;
+		default:
+			len = sprintf(buf + 1,
+				      "%s: protocol error: bad band #%d\n",
+				      me, buf[0] & 0xFF);
+			safe_write(err, buf+1, len);
+			return SIDEBAND_PROTOCOL_ERROR;
+		}
+	}
+	return 0;
+}
+
+/*
+ * fd is connected to the remote side; send the sideband data
+ * over multiplexed packet stream.
+ */
+ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
+{
+	ssize_t ssz = sz;
+	const char *p = data;
+
+	while (sz) {
+		unsigned n;
+		char hdr[5];
+
+		n = sz;
+		if (packet_max - 5 < n)
+			n = packet_max - 5;
+		sprintf(hdr, "%04x", n + 5);
+		hdr[4] = band;
+		safe_write(fd, hdr, 5);
+		safe_write(fd, p, n);
+		p += n;
+		sz -= n;
+	}
+	return ssz;
+}
diff --git a/sideband.h b/sideband.h
new file mode 100644
index 0000000000..4872106fa0
--- /dev/null
+++ b/sideband.h
@@ -0,0 +1,13 @@
+#ifndef SIDEBAND_H
+#define SIDEBAND_H
+
+#define SIDEBAND_PROTOCOL_ERROR -2
+#define SIDEBAND_REMOTE_ERROR -1
+
+#define DEFAULT_PACKET_MAX 1000
+#define LARGE_PACKET_MAX 65520
+
+int recv_sideband(const char *me, int in_stream, int out, int err, char *, int);
+ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max);
+
+#endif
diff --git a/upload-pack.c b/upload-pack.c
index 6ee08c6502..db56cef474 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -4,6 +4,7 @@
 #include "cache.h"
 #include "refs.h"
 #include "pkt-line.h"
+#include "sideband.h"
 #include "tag.h"
 #include "object.h"
 #include "commit.h"
@@ -25,6 +26,9 @@ static int use_thin_pack;
 static struct object_array have_obj;
 static struct object_array want_obj;
 static unsigned int timeout;
+/* 0 for no sideband,
+ * otherwise maximum packet size (up to 65520 bytes).
+ */
 static int use_sideband;
 
 static void reset_timeout(void)
@@ -39,45 +43,18 @@ static int strip(char *line, int len)
 	return len;
 }
 
-#define PACKET_MAX 1000
 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
 {
-	ssize_t ssz;
-	const char *p;
-
-	if (!data) {
-		if (!use_sideband)
-			return 0;
-		packet_flush(1);
+	if (use_sideband)
+		return send_sideband(1, fd, data, sz, use_sideband);
+	if (fd == 3)
+		/* emergency quit */
+		fd = 2;
+	if (fd == 2) {
+		xwrite(fd, data, sz);
+		return sz;
 	}
-
-	if (!use_sideband) {
-		if (fd == 3)
-			/* emergency quit */
-			fd = 2;
-		if (fd == 2) {
-			xwrite(fd, data, sz);
-			return sz;
-		}
-		return safe_write(fd, data, sz);
-	}
-	p = data;
-	ssz = sz;
-	while (sz) {
-		unsigned n;
-		char hdr[5];
-
-		n = sz;
-		if (PACKET_MAX - 5 < n)
-			n = PACKET_MAX - 5;
-		sprintf(hdr, "%04x", n + 5);
-		hdr[4] = fd;
-		safe_write(1, hdr, 5);
-		safe_write(1, p, n);
-		p += n;
-		sz -= n;
-	}
-	return ssz;
+	return safe_write(fd, data, sz);
 }
 
 static void create_pack_file(void)
@@ -314,7 +291,8 @@ static void create_pack_file(void)
 				goto fail;
 			fprintf(stderr, "flushed.\n");
 		}
-		send_client_data(1, NULL, 0);
+		if (use_sideband)
+			packet_flush(1);
 		return;
 	}
  fail:
@@ -498,8 +476,10 @@ static void receive_needs(void)
 			multi_ack = 1;
 		if (strstr(line+45, "thin-pack"))
 			use_thin_pack = 1;
-		if (strstr(line+45, "side-band"))
-			use_sideband = 1;
+		if (strstr(line+45, "side-band-64k"))
+			use_sideband = LARGE_PACKET_MAX;
+		else if (strstr(line+45, "side-band"))
+			use_sideband = DEFAULT_PACKET_MAX;
 
 		/* We have sent all our refs already, and the other end
 		 * should have chosen out of them; otherwise they are
@@ -521,7 +501,7 @@ static void receive_needs(void)
 
 static int send_ref(const char *refname, const unsigned char *sha1)
 {
-	static const char *capabilities = "multi_ack thin-pack side-band";
+	static const char *capabilities = "multi_ack thin-pack side-band side-band-64k";
 	struct object *o = parse_object(sha1);
 
 	if (!o)