35 files changed, 593 insertions, 309 deletions

diff --git a/Documentation/RelNotes-1.5.0.5.txt b/Documentation/RelNotes-1.5.0.5.txt
new file mode 100644
index 0000000000..aa86149d4f
--- /dev/null
+++ b/Documentation/RelNotes-1.5.0.5.txt
@@ -0,0 +1,28 @@
+GIT v1.5.0.5 Release Notes
+==========================
+
+Fixes since v1.5.0.3
+--------------------
+
+* Bugfixes
+
+  - git-merge (hence git-pull) did not refuse fast-forwarding
+    when the working tree had local changes that would have
+    conflicted with it.
+
+  - git.el does not add duplicate sign-off lines.
+
+  - git-commit shows the full stat of the resulting commit, not
+    just about the files in the current directory, when run from
+    a subdirectory.
+
+  - "git-checkout -m '@{8 hours ago}'" had a funny failure from
+    eval; fixed.
+
+  - git-gui updates.
+
+* Documentation updates
+
+* User manual updates
+
+
diff --git a/Documentation/config.txt b/Documentation/config.txt
index 953acaee4c..cf1e040381 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -240,6 +240,19 @@ the largest projects.  You probably do not need to adjust this value.
 +
 Common unit suffixes of 'k', 'm', or 'g' are supported.
 
+core.deltaBaseCacheLimit::
+	Maximum number of bytes to reserve for caching base objects
+	that multiple deltafied objects reference.  By storing the
+	entire decompressed base objects in a cache Git is able
+	to avoid unpacking and decompressing frequently used base
+	objects multiple times.
++
+Default is 16 MiB on all platforms.  This should be reasonable
+for all users/operating systems, except on the largest projects.
+You probably do not need to adjust this value.
++
+Common unit suffixes of 'k', 'm', or 'g' are supported.
+
 alias.*::
 	Command aliases for the gitlink:git[1] command wrapper - e.g.
 	after defining "alias.last = cat-file commit HEAD", the invocation
@@ -460,7 +473,7 @@ merge.summary::
 merge.tool::
 	Controls which merge resolution program is used by
 	gitlink:git-mergetool[l].  Valid values are: "kdiff3", "tkdiff",
-	"meld", "xxdiff", "emerge"
+	"meld", "xxdiff", "emerge", "vimdiff"
 
 merge.verbosity::
 	Controls the amount of output shown by the recursive merge
diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index d8696b7b36..77a3f78dd7 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -159,5 +159,10 @@
 -w::
 	Shorthand for "--ignore-all-space".
 
+--exit-code::
+	Make the program exit with codes similar to diff(1).
+	That is, it exits with 1 if there were differences and
+	0 means no differences.
+
 For more detailed explanation on these common options, see also
 link:diffcore.html[diffcore documentation].
diff --git a/Documentation/git-mergetool.txt b/Documentation/git-mergetool.txt
index ae69a0eb83..5baaaca0b5 100644
--- a/Documentation/git-mergetool.txt
+++ b/Documentation/git-mergetool.txt
@@ -25,7 +25,7 @@ OPTIONS
 -t or --tool=<tool>::
 	Use the merge resolution program specified by <tool>.
 	Valid merge tools are:
-	kdiff3, tkdiff, meld, xxdiff, and emerge.
+	kdiff3, tkdiff, meld, xxdiff, emerge, and vimdiff.
 
 	If a merge resolution program is not specified, 'git mergetool'
 	will use the configuration variable merge.tool.  If the
diff --git a/Documentation/git-send-email.txt b/Documentation/git-send-email.txt
index 9b3aabb6fe..682313e95d 100644
--- a/Documentation/git-send-email.txt
+++ b/Documentation/git-send-email.txt
@@ -60,7 +60,8 @@ The --cc option must be repeated for each user you want on the cc list.
 	is not set, this will be prompted for.
 
 --no-signed-off-by-cc::
-	Do not add emails found in Signed-off-by: lines to the cc list.
+	Do not add emails found in Signed-off-by: or Cc: lines to the
+	cc list.
 
 --quiet::
 	Make git-send-email less verbose.  One line per email should be
diff --git a/Documentation/git.txt b/Documentation/git.txt
index e875e8318d..31397dc539 100644
--- a/Documentation/git.txt
+++ b/Documentation/git.txt
@@ -35,7 +35,9 @@ ifdef::stalenotes[]
 You are reading the documentation for the latest version of git.
 Documentation for older releases are available here:
 
-* link:v1.5.0.3/git.html[documentation for release 1.5.0.3]
+* link:v1.5.0.5/git.html[documentation for release 1.5.0.5]
+
+* link:v1.5.0.5/RelNotes-1.5.0.5.txt[release notes for 1.5.0.5]
 
 * link:v1.5.0.3/RelNotes-1.5.0.3.txt[release notes for 1.5.0.3]
 
diff --git a/builtin-bundle.c b/builtin-bundle.c
index 786808081b..0a9b73867f 100644
--- a/builtin-bundle.c
+++ b/builtin-bundle.c
@@ -4,7 +4,7 @@
 #include "diff.h"
 #include "revision.h"
 #include "list-objects.h"
-#include "exec_cmd.h"
+#include "run-command.h"
 
 /*
  * Basic handler for bundle files to connect repositories via sneakernet.
@@ -99,67 +99,6 @@ static int read_header(const char *path, struct bundle_header *header) {
 	return fd;
 }
 
-/* if in && *in >= 0, take that as input file descriptor instead */
-static int fork_with_pipe(const char **argv, int *in, int *out)
-{
-	int needs_in, needs_out;
-	int fdin[2], fdout[2], pid;
-
-	needs_in = in && *in < 0;
-	if (needs_in) {
-		if (pipe(fdin) < 0)
-			return error("could not setup pipe");
-		*in = fdin[1];
-	}
-
-	needs_out = out && *out < 0;
-	if (needs_out) {
-		if (pipe(fdout) < 0)
-			return error("could not setup pipe");
-		*out = fdout[0];
-	}
-
-	if ((pid = fork()) < 0) {
-		if (needs_in) {
-			close(fdin[0]);
-			close(fdin[1]);
-		}
-		if (needs_out) {
-			close(fdout[0]);
-			close(fdout[1]);
-		}
-		return error("could not fork");
-	}
-	if (!pid) {
-		if (needs_in) {
-			dup2(fdin[0], 0);
-			close(fdin[0]);
-			close(fdin[1]);
-		} else if (in) {
-			dup2(*in, 0);
-			close(*in);
-		}
-		if (needs_out) {
-			dup2(fdout[1], 1);
-			close(fdout[0]);
-			close(fdout[1]);
-		} else if (out) {
-			dup2(*out, 1);
-			close(*out);
-		}
-		exit(execv_git_cmd(argv));
-	}
-	if (needs_in)
-		close(fdin[0]);
-	else if (in)
-		close(*in);
-	if (needs_out)
-		close(fdout[1]);
-	else if (out)
-		close(*out);
-	return pid;
-}
-
 static int list_refs(struct ref_list *r, int argc, const char **argv)
 {
 	int i;
@@ -263,9 +202,10 @@ static int create_bundle(struct bundle_header *header, const char *path,
 	int bundle_fd = -1;
 	const char **argv_boundary = xmalloc((argc + 4) * sizeof(const char *));
 	const char **argv_pack = xmalloc(5 * sizeof(const char *));
-	int pid, in, out, i, status, ref_count = 0;
+	int i, ref_count = 0;
 	char buffer[1024];
 	struct rev_info revs;
+	struct child_process rls;
 
 	bundle_fd = (!strcmp(path, "-") ? 1 :
 			open(path, O_CREAT | O_EXCL | O_WRONLY, 0666));
@@ -285,11 +225,13 @@ static int create_bundle(struct bundle_header *header, const char *path,
 	argv_boundary[1] = "--boundary";
 	argv_boundary[2] = "--pretty=oneline";
 	argv_boundary[argc + 2] = NULL;
-	out = -1;
-	pid = fork_with_pipe(argv_boundary, NULL, &out);
-	if (pid < 0)
+	memset(&rls, 0, sizeof(rls));
+	rls.argv = argv_boundary;
+	rls.out = -1;
+	rls.git_cmd = 1;
+	if (start_command(&rls))
 		return -1;
-	while ((i = read_string(out, buffer, sizeof(buffer))) > 0) {
+	while ((i = read_string(rls.out, buffer, sizeof(buffer))) > 0) {
 		unsigned char sha1[20];
 		if (buffer[0] == '-') {
 			write_or_die(bundle_fd, buffer, i);
@@ -303,11 +245,8 @@ static int create_bundle(struct bundle_header *header, const char *path,
 			object->flags |= SHOWN;
 		}
 	}
-	while ((i = waitpid(pid, &status, 0)) < 0)
-		if (errno != EINTR)
-			return error("rev-list died");
-	if (!WIFEXITED(status) || WEXITSTATUS(status))
-		return error("rev-list died %d", WEXITSTATUS(status));
+	if (finish_command(&rls))
+		return error("rev-list died");
 
 	/* write references */
 	argc = setup_revisions(argc, argv, &revs, NULL);
@@ -352,26 +291,23 @@ static int create_bundle(struct bundle_header *header, const char *path,
 	argv_pack[2] = "--stdout";
 	argv_pack[3] = "--thin";
 	argv_pack[4] = NULL;
-	in = -1;
-	out = bundle_fd;
-	pid = fork_with_pipe(argv_pack, &in, &out);
-	if (pid < 0)
+	memset(&rls, 0, sizeof(rls));
+	rls.argv = argv_pack;
+	rls.in = -1;
+	rls.out = bundle_fd;
+	rls.git_cmd = 1;
+	if (start_command(&rls))
 		return error("Could not spawn pack-objects");
 	for (i = 0; i < revs.pending.nr; i++) {
 		struct object *object = revs.pending.objects[i].item;
 		if (object->flags & UNINTERESTING)
-			write(in, "^", 1);
-		write(in, sha1_to_hex(object->sha1), 40);
-		write(in, "\n", 1);
+			write(rls.in, "^", 1);
+		write(rls.in, sha1_to_hex(object->sha1), 40);
+		write(rls.in, "\n", 1);
 	}
-	close(in);
-	while (waitpid(pid, &status, 0) < 0)
-		if (errno != EINTR)
-			return -1;
-	if (!WIFEXITED(status) || WEXITSTATUS(status))
+	if (finish_command(&rls))
 		return error ("pack-objects died");
-
-	return status;
+	return 0;
 }
 
 static int unbundle(struct bundle_header *header, int bundle_fd,
@@ -379,22 +315,17 @@ static int unbundle(struct bundle_header *header, int bundle_fd,
 {
 	const char *argv_index_pack[] = {"index-pack",
 		"--fix-thin", "--stdin", NULL};
-	int pid, status, dev_null;
+	struct child_process ip;
 
 	if (verify_bundle(header, 0))
 		return -1;
-	dev_null = open("/dev/null", O_WRONLY);
-	if (dev_null < 0)
-		return error("Could not open /dev/null");
-	pid = fork_with_pipe(argv_index_pack, &bundle_fd, &dev_null);
-	if (pid < 0)
-		return error("Could not spawn index-pack");
-	while (waitpid(pid, &status, 0) < 0)
-		if (errno != EINTR)
-			return error("index-pack died");
-	if (!WIFEXITED(status) || WEXITSTATUS(status))
-		return error("index-pack exited with status %d",
-				WEXITSTATUS(status));
+	memset(&ip, 0, sizeof(ip));
+	ip.argv = argv_index_pack;
+	ip.in = bundle_fd;
+	ip.no_stdout = 1;
+	ip.git_cmd = 1;
+	if (run_command(&ip))
+		return error("index-pack died");
 	return list_heads(header, argc, argv);
 }
 
diff --git a/builtin-diff-files.c b/builtin-diff-files.c
index aec8338429..6ba5077a2b 100644
--- a/builtin-diff-files.c
+++ b/builtin-diff-files.c
@@ -17,6 +17,7 @@ int cmd_diff_files(int argc, const char **argv, const char *prefix)
 {
 	struct rev_info rev;
 	int nongit = 0;
+	int result;
 
 	prefix = setup_git_directory_gently(&nongit);
 	init_revisions(&rev, prefix);
@@ -29,5 +30,6 @@ int cmd_diff_files(int argc, const char **argv, const char *prefix)
 		argc = setup_revisions(argc, argv, &rev, NULL);
 	if (!rev.diffopt.output_format)
 		rev.diffopt.output_format = DIFF_FORMAT_RAW;
-	return run_diff_files_cmd(&rev, argc, argv);
+	result = run_diff_files_cmd(&rev, argc, argv);
+	return rev.diffopt.exit_with_status ? rev.diffopt.has_changes: result;
 }
diff --git a/builtin-diff-index.c b/builtin-diff-index.c
index 083599d5c4..d90eba95a6 100644
--- a/builtin-diff-index.c
+++ b/builtin-diff-index.c
@@ -14,6 +14,7 @@ int cmd_diff_index(int argc, const char **argv, const char *prefix)
 	struct rev_info rev;
 	int cached = 0;
 	int i;
+	int result;
 
 	init_revisions(&rev, prefix);
 	git_config(git_default_config); /* no "diff" UI options */
@@ -42,5 +43,6 @@ int cmd_diff_index(int argc, const char **argv, const char *prefix)
 		perror("read_cache");
 		return -1;
 	}
-	return run_diff_index(&rev, cached);
+	result = run_diff_index(&rev, cached);
+	return rev.diffopt.exit_with_status ? rev.diffopt.has_changes: result;
 }
diff --git a/builtin-diff-tree.c b/builtin-diff-tree.c
index 24cb2d7f84..0b591c8716 100644
--- a/builtin-diff-tree.c
+++ b/builtin-diff-tree.c
@@ -118,7 +118,8 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
 	}
 
 	if (!read_stdin)
-		return 0;
+		return opt->diffopt.exit_with_status ?
+		    opt->diffopt.has_changes: 0;
 
 	if (opt->diffopt.detect_rename)
 		opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
@@ -133,5 +134,5 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
 		else
 			diff_tree_stdin(line);
 	}
-	return 0;
+	return opt->diffopt.exit_with_status ? opt->diffopt.has_changes: 0;
 }
diff --git a/builtin-diff.c b/builtin-diff.c
index 4efbb8237b..21d13f0b30 100644
--- a/builtin-diff.c
+++ b/builtin-diff.c
@@ -190,6 +190,7 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 	const char *path = NULL;
 	struct blobinfo blob[2];
 	int nongit = 0;
+	int result = 0;
 
 	/*
 	 * We could get N tree-ish in the rev.pending_objects list.
@@ -292,17 +293,17 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 	if (!ents) {
 		switch (blobs) {
 		case 0:
-			return run_diff_files_cmd(&rev, argc, argv);
+			result = run_diff_files_cmd(&rev, argc, argv);
 			break;
 		case 1:
 			if (paths != 1)
 				usage(builtin_diff_usage);
-			return builtin_diff_b_f(&rev, argc, argv, blob, path);
+			result = builtin_diff_b_f(&rev, argc, argv, blob, path);
 			break;
 		case 2:
 			if (paths)
 				usage(builtin_diff_usage);
-			return builtin_diff_blobs(&rev, argc, argv, blob);
+			result = builtin_diff_blobs(&rev, argc, argv, blob);
 			break;
 		default:
 			usage(builtin_diff_usage);
@@ -311,19 +312,21 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 	else if (blobs)
 		usage(builtin_diff_usage);
 	else if (ents == 1)
-		return builtin_diff_index(&rev, argc, argv);
+		result = builtin_diff_index(&rev, argc, argv);
 	else if (ents == 2)
-		return builtin_diff_tree(&rev, argc, argv, ent);
+		result = builtin_diff_tree(&rev, argc, argv, ent);
 	else if ((ents == 3) && (ent[0].item->flags & UNINTERESTING)) {
 		/* diff A...B where there is one sane merge base between
 		 * A and B.  We have ent[0] == merge-base, ent[1] == A,
 		 * and ent[2] == B.  Show diff between the base and B.
 		 */
 		ent[1] = ent[2];
-		return builtin_diff_tree(&rev, argc, argv, ent);
+		result = builtin_diff_tree(&rev, argc, argv, ent);
 	}
 	else
-		return builtin_diff_combined(&rev, argc, argv,
+		result = builtin_diff_combined(&rev, argc, argv,
 					     ent, ents);
-	usage(builtin_diff_usage);
+	if (rev.diffopt.exit_with_status)
+		result = rev.diffopt.has_changes;
+	return result;
 }
diff --git a/builtin-push.c b/builtin-push.c
index 6ab9a28e8c..70b1168fa6 100644
--- a/builtin-push.c
+++ b/builtin-push.c
@@ -323,10 +323,10 @@ static int do_push(const char *repo)
 		int dest_refspec_nr = refspec_nr;
 		const char **dest_refspec = refspec;
 		const char *dest = uri[i];
-		const char *sender = "git-send-pack";
+		const char *sender = "send-pack";
 		if (!prefixcmp(dest, "http://") ||
 		    !prefixcmp(dest, "https://"))
-			sender = "git-http-push";
+			sender = "http-push";
 		else if (thin)
 			argv[dest_argc++] = "--thin";
 		argv[0] = sender;
@@ -336,7 +336,7 @@ static int do_push(const char *repo)
 		argv[dest_argc] = NULL;
 		if (verbose)
 			fprintf(stderr, "Pushing to %s\n", dest);
-		err = run_command_v_opt(argv, 0);
+		err = run_command_v_opt(argv, RUN_GIT_CMD);
 		if (!err)
 			continue;
 		switch (err) {
diff --git a/builtin-revert.c b/builtin-revert.c
index 652eece5ad..f3f3f5c6ee 100644
--- a/builtin-revert.c
+++ b/builtin-revert.c
@@ -235,8 +235,8 @@ static int revert_or_cherry_pick(int argc, const char **argv)
 	unsigned char head[20];
 	struct commit *base, *next;
 	int i;
-	char *oneline, *encoding, *reencoded_message = NULL;
-	const char *message;
+	char *oneline, *reencoded_message = NULL;
+	const char *message, *encoding;
 
 	git_config(git_default_config);
 	me = action == REVERT ? "revert" : "cherry-pick";
diff --git a/cache.h b/cache.h
index 3818e10f8c..1b50a742a3 100644
--- a/cache.h
+++ b/cache.h
@@ -228,6 +228,7 @@ extern const char *apply_default_whitespace;
 extern int zlib_compression_level;
 extern size_t packed_git_window_size;
 extern size_t packed_git_limit;
+extern size_t delta_base_cache_limit;
 extern int auto_crlf;
 
 #define GIT_REPO_VERSION 0
@@ -451,7 +452,7 @@ extern int check_repository_format_version(const char *var, const char *value);
 extern char git_default_email[MAX_GITNAME];
 extern char git_default_name[MAX_GITNAME];
 
-extern char *git_commit_encoding;
+extern const char *git_commit_encoding;
 extern const char *git_log_output_encoding;
 
 extern int copy_fd(int ifd, int ofd);
diff --git a/config.c b/config.c
index d537311ae1..6479855723 100644
--- a/config.c
+++ b/config.c
@@ -331,6 +331,11 @@ int git_default_config(const char *var, const char *value)
 		return 0;
 	}
 
+	if (!strcmp(var, "core.deltabasecachelimit")) {
+		delta_base_cache_limit = git_config_int(var, value);
+		return 0;
+	}
+
 	if (!strcmp(var, "core.autocrlf")) {
 		if (value && !strcasecmp(value, "input")) {
 			auto_crlf = -1;
diff --git a/connect.c b/connect.c
index 8a8a13bb72..5048653639 100644
--- a/connect.c
+++ b/connect.c
@@ -3,6 +3,7 @@
 #include "pkt-line.h"
 #include "quote.h"
 #include "refs.h"
+#include "run-command.h"
 
 static char *server_capabilities;
 
@@ -598,8 +599,8 @@ static void git_proxy_connect(int fd[2], char *host)
 {
 	const char *port = STR(DEFAULT_GIT_PORT);
 	char *colon, *end;
-	int pipefd[2][2];
-	pid_t pid;
+	const char *argv[4];
+	struct child_process proxy;
 
 	if (host[0] == '[') {
 		end = strchr(host + 1, ']');
@@ -618,25 +619,18 @@ static void git_proxy_connect(int fd[2], char *host)
 		port = colon + 1;
 	}
 
-	if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
-		die("unable to create pipe pair for communication");
-	pid = fork();
-	if (!pid) {
-		dup2(pipefd[1][0], 0);
-		dup2(pipefd[0][1], 1);
-		close(pipefd[0][0]);
-		close(pipefd[0][1]);
-		close(pipefd[1][0]);
-		close(pipefd[1][1]);
-		execlp(git_proxy_command, git_proxy_command, host, port, NULL);
-		die("exec failed");
-	}
-	if (pid < 0)
-		die("fork failed");
-	fd[0] = pipefd[0][0];
-	fd[1] = pipefd[1][1];
-	close(pipefd[0][1]);
-	close(pipefd[1][0]);
+	argv[0] = git_proxy_command;
+	argv[1] = host;
+	argv[2] = port;
+	argv[3] = NULL;
+	memset(&proxy, 0, sizeof(proxy));
+	proxy.argv = argv;
+	proxy.in = -1;
+	proxy.out = -1;
+	if (start_command(&proxy))
+		die("cannot start proxy %s", argv[0]);
+	fd[0] = proxy.out; /* read from proxy stdout */
+	fd[1] = proxy.in;  /* write to proxy stdin */
 }
 
 #define MAX_CMD_LEN 1024
diff --git a/diff-lib.c b/diff-lib.c
index 6abb981534..5c5b05bfe3 100644
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -170,8 +170,10 @@ static int handle_diff_files_args(struct rev_info *revs,
 		else if (!strcmp(argv[1], "--theirs"))
 			revs->max_count = 3;
 		else if (!strcmp(argv[1], "-n") ||
-				!strcmp(argv[1], "--no-index"))
+				!strcmp(argv[1], "--no-index")) {
 			revs->max_count = -2;
+			revs->diffopt.exit_with_status = 1;
+		}
 		else if (!strcmp(argv[1], "-q"))
 			*silent = 1;
 		else
@@ -237,6 +239,7 @@ int setup_diff_no_index(struct rev_info *revs,
 			break;
 		} else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
 			i = argc - 3;
+			revs->diffopt.exit_with_status = 1;
 			break;
 		}
 	if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&
@@ -321,6 +324,9 @@ int run_diff_files(struct rev_info *revs, int silent_on_removed)
 		struct cache_entry *ce = active_cache[i];
 		int changed;
 
+		if (revs->diffopt.quiet && revs->diffopt.has_changes)
+			break;
+
 		if (!ce_path_match(ce, revs->prune_data))
 			continue;
 
@@ -562,6 +568,9 @@ static int diff_cache(struct rev_info *revs,
 		struct cache_entry *ce = *ac;
 		int same = (entries > 1) && ce_same_name(ce, ac[1]);
 
+		if (revs->diffopt.quiet && revs->diffopt.has_changes)
+			break;
+
 		if (!ce_path_match(ce, pathspec))
 			goto skip_entry;
 
diff --git a/diff.c b/diff.c
index 954ca83e0b..d8f9242ea8 100644
--- a/diff.c
+++ b/diff.c
@@ -1958,6 +1958,23 @@ int diff_setup_done(struct diff_options *options)
 	if (options->abbrev <= 0 || 40 < options->abbrev)
 		options->abbrev = 40; /* full */
 
+	/*
+	 * It does not make sense to show the first hit we happened
+	 * to have found.  It does not make sense not to return with
+	 * exit code in such a case either.
+	 */
+	if (options->quiet) {
+		options->output_format = DIFF_FORMAT_NO_OUTPUT;
+		options->exit_with_status = 1;
+	}
+
+	/*
+	 * If we postprocess in diffcore, we cannot simply return
+	 * upon the first hit.  We need to run diff as usual.
+	 */
+	if (options->pickaxe || options->filter)
+		options->quiet = 0;
+
 	return 0;
 }
 
@@ -2134,6 +2151,10 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		options->color_diff = options->color_diff_words = 1;
 	else if (!strcmp(arg, "--no-renames"))
 		options->detect_rename = 0;
+	else if (!strcmp(arg, "--exit-code"))
+		options->exit_with_status = 1;
+	else if (!strcmp(arg, "--quiet"))
+		options->quiet = 1;
 	else
 		return 0;
 	return 1;
@@ -2898,6 +2919,8 @@ static void diffcore_apply_filter(const char *filter)
 
 void diffcore_std(struct diff_options *options)
 {
+	if (options->quiet)
+		return;
 	if (options->break_opt != -1)
 		diffcore_break(options->break_opt);
 	if (options->detect_rename)
@@ -2910,18 +2933,11 @@ void diffcore_std(struct diff_options *options)
 		diffcore_order(options->orderfile);
 	diff_resolve_rename_copy();
 	diffcore_apply_filter(options->filter);
-}
 
-
-void diffcore_std_no_resolve(struct diff_options *options)
-{
-	if (options->pickaxe)
-		diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
-	if (options->orderfile)
-		diffcore_order(options->orderfile);
-	diffcore_apply_filter(options->filter);
+	options->has_changes = !!diff_queued_diff.nr;
 }
 
+
 void diff_addremove(struct diff_options *options,
 		    int addremove, unsigned mode,
 		    const unsigned char *sha1,
@@ -2957,6 +2973,7 @@ void diff_addremove(struct diff_options *options,
 		fill_filespec(two, sha1, mode);
 
 	diff_queue(&diff_queued_diff, one, two);
+	options->has_changes = 1;
 }
 
 void diff_change(struct diff_options *options,
@@ -2982,6 +2999,7 @@ void diff_change(struct diff_options *options,
 	fill_filespec(two, new_sha1, new_mode);
 
 	diff_queue(&diff_queued_diff, one, two);
+	options->has_changes = 1;
 }
 
 void diff_unmerge(struct diff_options *options,
diff --git a/diff.h b/diff.h
index 4b435e8b19..a0d2ce1399 100644
--- a/diff.h
+++ b/diff.h
@@ -56,7 +56,10 @@ struct diff_options {
 		 silent_on_remove:1,
 		 find_copies_harder:1,
 		 color_diff:1,
-		 color_diff_words:1;
+		 color_diff_words:1,
+		 has_changes:1,
+		 quiet:1,
+		 exit_with_status:1;
 	int context;
 	int break_opt;
 	int detect_rename;
@@ -170,8 +173,6 @@ extern int diff_setup_done(struct diff_options *);
 
 extern void diffcore_std(struct diff_options *);
 
-extern void diffcore_std_no_resolve(struct diff_options *);
-
 #define COMMON_DIFF_OPTIONS_HELP \
 "\ncommon diff options:\n" \
 "  -z            output diff-raw with lines terminated with NUL.\n" \
diff --git a/environment.c b/environment.c
index 0151ad0722..22316597df 100644
--- a/environment.c
+++ b/environment.c
@@ -20,13 +20,14 @@ int is_bare_repository_cfg = -1; /* unspecified */
 int log_all_ref_updates = -1; /* unspecified */
 int warn_ambiguous_refs = 1;
 int repository_format_version;
-char *git_commit_encoding;
+const char *git_commit_encoding;
 const char *git_log_output_encoding;
 int shared_repository = PERM_UMASK;
 const char *apply_default_whitespace;
 int zlib_compression_level = Z_DEFAULT_COMPRESSION;
 size_t packed_git_window_size = DEFAULT_PACKED_GIT_WINDOW_SIZE;
 size_t packed_git_limit = DEFAULT_PACKED_GIT_LIMIT;
+size_t delta_base_cache_limit = 16 * 1024 * 1024;
 int pager_in_use;
 int pager_use_color = 1;
 int auto_crlf = 0;	/* 1: both ways, -1: only when adding git objects */
diff --git a/git-cvsserver.perl b/git-cvsserver.perl
index 65fcc84049..68aa75255e 100755
--- a/git-cvsserver.perl
+++ b/git-cvsserver.perl
@@ -947,6 +947,7 @@ sub req_update
 
             # we need to merge with the local changes ( M=successful merge, C=conflict merge )
             $log->info("Merging $file_local, $file_old, $file_new");
+            print "M Merging differences between 1.$oldmeta->{revision} and 1.$meta->{revision} into $filename\n";
 
             $log->debug("Temporary directory for merge is $dir");
 
@@ -973,6 +974,7 @@ sub req_update
             elsif ( $return == 1 )
             {
                 $log->info("Merged with conflicts");
+                print "E cvs update: conflicts found in $filename\n";
                 print "M C $filename\n";
 
                 # Don't want to actually _DO_ the update if -n specified
@@ -1067,6 +1069,7 @@ sub req_ci
     $log->info("Created index '$file_index' with for head $state->{module} - exit status $?");
 
     my @committedfiles = ();
+    my %oldmeta;
 
     # foreach file specified on the command line ...
     foreach my $filename ( @{$state->{args}} )
@@ -1077,6 +1080,7 @@ sub req_ci
         next unless ( exists $state->{entries}{$filename}{modified_filename} or not $state->{entries}{$filename}{unchanged} );
 
         my $meta = $updater->getmeta($filename);
+	$oldmeta{$filename} = $meta;
 
         my $wrev = revparse($filename);
 
@@ -1205,11 +1209,18 @@ sub req_ci
 
         $log->debug("Checked-in $dirpart : $filename");
 
+	print "M $state->{CVSROOT}/$state->{module}/$filename,v  <--  $dirpart$filepart\n";
         if ( defined $meta->{filehash} && $meta->{filehash} eq "deleted" )
         {
+            print "M new revision: delete; previous revision: 1.$oldmeta{$filename}{revision}\n";
             print "Remove-entry $dirpart\n";
             print "$filename\n";
         } else {
+            if ($meta->{revision} == 1) {
+	        print "M initial revision: 1.1\n";
+            } else {
+	        print "M new revision: 1.$meta->{revision}; previous revision: 1.$oldmeta{$filename}{revision}\n";
+            }
             print "Checked-in $dirpart\n";
             print "$filename\n";
             my $kopts = kopts_from_path($filepart);
@@ -1295,7 +1306,7 @@ sub req_status
         }
         if ( defined($meta->{revision}) )
         {
-            print "M Repository revision:\t1." . $meta->{revision} . "\t$state->{repository}/$filename,v\n";
+            print "M Repository revision:\t1." . $meta->{revision} . "\t$state->{CVSROOT}/$state->{module}/$filename,v\n";
             print "M Sticky Tag:\t\t(none)\n";
             print "M Sticky Date:\t\t(none)\n";
             print "M Sticky Options:\t\t(none)\n";
diff --git a/git-mergetool.sh b/git-mergetool.sh
index 52386a5443..7942fd0b64 100755
--- a/git-mergetool.sh
+++ b/git-mergetool.sh
@@ -185,9 +185,9 @@ merge_file () {
 		mv -- "$BACKUP" "$path.orig"
 	    fi
 	    ;;
-	meld)
+	meld|vimdiff)
 	    touch "$BACKUP"
-	    meld -- "$LOCAL" "$path" "$REMOTE"
+	    $merge_tool -- "$LOCAL" "$path" "$REMOTE"
 	    if test "$path" -nt "$BACKUP" ; then
 		status=0;
 	    else
@@ -288,10 +288,15 @@ done
 
 if test -z "$merge_tool"; then
     merge_tool=`git-config merge.tool`
-    if test $merge_tool = kdiff3 -o $merge_tool = tkdiff -o \
-	$merge_tool = xxdiff -o $merge_tool = meld ; then
-	unset merge_tool
-    fi
+    case "$merge_tool" in
+	kdiff3 | tkdiff | xxdiff | meld | emerge | vimdiff)
+	    ;; # happy
+	*)
+	    echo >&2 "git config option merge.tool set to unknown tool: $merge_tool"
+	    echo >&2 "Resetting to default..."
+	    unset merge_tool
+	    ;;
+    esac
 fi
 
 if test -z "$merge_tool" ; then
@@ -305,6 +310,8 @@ if test -z "$merge_tool" ; then
 	merge_tool=meld
     elif type emacs >/dev/null 2>&1; then
 	merge_tool=emerge
+    elif type vimdiff >/dev/null 2>&1; then
+	merge_tool=vimdiff
     else
 	echo "No available merge resolution programs available."
 	exit 1
@@ -312,7 +319,7 @@ if test -z "$merge_tool" ; then
 fi
 
 case "$merge_tool" in
-    kdiff3|tkdiff|meld|xxdiff)
+    kdiff3|tkdiff|meld|xxdiff|vimdiff)
 	if ! type "$merge_tool" > /dev/null 2>&1; then
 	    echo "The merge tool $merge_tool is not available"
 	    exit 1
diff --git a/git-send-email.perl b/git-send-email.perl
index 6989c0260f..ae50990d08 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -65,8 +65,8 @@ Options:
                   Defaults to on.
 
    --no-signed-off-cc Suppress the automatic addition of email addresses
-                 that appear in a Signed-off-by: line, to the cc: list.
-		 Note: Using this option is not recommended.
+                 that appear in Signed-off-by: or Cc: lines to the cc:
+                 list.  Note: Using this option is not recommended.
 
    --smtp-server  If set, specifies the outgoing SMTP server to use.
                   Defaults to localhost.
@@ -572,8 +572,8 @@ foreach my $t (@files) {
 			}
 		} else {
 			$message .=  $_;
-			if (/^Signed-off-by: (.*)$/i && !$no_signed_off_cc) {
-				my $c = $1;
+			if (/^(Signed-off-by|Cc): (.*)$/i && !$no_signed_off_cc) {
+				my $c = $2;
 				chomp $c;
 				push @cc, $c;
 				printf("(sob) Adding cc: %s from line '%s'\n",
diff --git a/merge-index.c b/merge-index.c
index 7027d78659..6df43944b0 100644
--- a/merge-index.c
+++ b/merge-index.c
@@ -1,4 +1,5 @@
 #include "cache.h"
+#include "run-command.h"
 
 static const char *pgm;
 static const char *arguments[8];
@@ -7,24 +8,10 @@ static int err;
 
 static void run_program(void)
 {
-	pid_t pid = fork();
-	int status;
-
-	if (pid < 0)
-		die("unable to fork");
-	if (!pid) {
-		execlp(pgm, arguments[0],
-			    arguments[1],
-			    arguments[2],
-			    arguments[3],
-			    arguments[4],
-			    arguments[5],
-			    arguments[6],
-			    arguments[7],
-			    NULL);
-		die("unable to execute '%s'", pgm);
-	}
-	if (waitpid(pid, &status, 0) < 0 || !WIFEXITED(status) || WEXITSTATUS(status)) {
+	struct child_process child;
+	memset(&child, 0, sizeof(child));
+	child.argv = arguments;
+	if (run_command(&child)) {
 		if (one_shot) {
 			err++;
 		} else {
diff --git a/receive-pack.c b/receive-pack.c
index 7cf58782e3..26aa26bcb5 100644
--- a/receive-pack.c
+++ b/receive-pack.c
@@ -382,10 +382,10 @@ static const char *unpack(void)
 		}
 	} else {
 		const char *keeper[6];
-		int fd[2], s, len, status;
-		pid_t pid;
+		int s, len, status;
 		char keep_arg[256];
 		char packname[46];
+		struct child_process ip;
 
 		s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
 		if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
@@ -397,20 +397,12 @@ static const char *unpack(void)
 		keeper[3] = hdr_arg;
 		keeper[4] = keep_arg;
 		keeper[5] = NULL;
-
-		if (pipe(fd) < 0)
-			return "index-pack pipe failed";
-		pid = fork();
-		if (pid < 0)
+		memset(&ip, 0, sizeof(ip));
+		ip.argv = keeper;
+		ip.out = -1;
+		ip.git_cmd = 1;
+		if (start_command(&ip))
 			return "index-pack fork failed";
-		if (!pid) {
-			dup2(fd[1], 1);
-			close(fd[1]);
-			close(fd[0]);
-			execv_git_cmd(keeper);
-			die("execv of index-pack failed");
-		}
-		close(fd[1]);
 
 		/*
 		 * The first thing we expects from index-pack's output
@@ -420,9 +412,8 @@ static const char *unpack(void)
 		 * later on.  If we don't get that then tough luck with it.
 		 */
 		for (len = 0;
-		     len < 46 && (s = xread(fd[0], packname+len, 46-len)) > 0;
+		     len < 46 && (s = xread(ip.out, packname+len, 46-len)) > 0;
 		     len += s);
-		close(fd[0]);
 		if (len == 46 && packname[45] == '\n' &&
 		    memcmp(packname, "keep\t", 5) == 0) {
 			char path[PATH_MAX];
@@ -432,14 +423,8 @@ static const char *unpack(void)
 			pack_lockfile = xstrdup(path);
 		}
 
-		/* Then wrap our index-pack process. */
-		while (waitpid(pid, &status, 0) < 0)
-			if (errno != EINTR)
-				return "waitpid failed";
-		if (WIFEXITED(status)) {
-			int code = WEXITSTATUS(status);
-			if (code)
-				return "index-pack exited with error code";
+		status = finish_command(&ip);
+		if (!status) {
 			reprepare_packed_git();
 			return NULL;
 		}
diff --git a/revision.c b/revision.c
index 3c2eb125e6..bcdb6a1212 100644
--- a/revision.c
+++ b/revision.c
@@ -213,6 +213,13 @@ static int everybody_uninteresting(struct commit_list *orig)
 	return 1;
 }
 
+/*
+ * The goal is to get REV_TREE_NEW as the result only if the
+ * diff consists of all '+' (and no other changes), and
+ * REV_TREE_DIFFERENT otherwise (of course if the trees are
+ * the same we want REV_TREE_SAME).  That means that once we
+ * get to REV_TREE_DIFFERENT, we do not have to look any further.
+ */
 static int tree_difference = REV_TREE_SAME;
 
 static void file_add_remove(struct diff_options *options,
@@ -236,6 +243,8 @@ static void file_add_remove(struct diff_options *options,
 		diff = REV_TREE_NEW;
 	}
 	tree_difference = diff;
+	if (tree_difference == REV_TREE_DIFFERENT)
+		options->has_changes = 1;
 }
 
 static void file_change(struct diff_options *options,
@@ -245,6 +254,7 @@ static void file_change(struct diff_options *options,
 		 const char *base, const char *path)
 {
 	tree_difference = REV_TREE_DIFFERENT;
+	options->has_changes = 1;
 }
 
 int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
@@ -254,6 +264,7 @@ int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
 	if (!t2)
 		return REV_TREE_DIFFERENT;
 	tree_difference = REV_TREE_SAME;
+	revs->pruning.has_changes = 0;
 	if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 			   &revs->pruning) < 0)
 		return REV_TREE_DIFFERENT;
@@ -277,11 +288,12 @@ int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
 	empty.buf = "";
 	empty.size = 0;
 
-	tree_difference = 0;
+	tree_difference = REV_TREE_SAME;
+	revs->pruning.has_changes = 0;
 	retval = diff_tree(&empty, &real, "", &revs->pruning);
 	free(tree);
 
-	return retval >= 0 && !tree_difference;
+	return retval >= 0 && (tree_difference == REV_TREE_SAME);
 }
 
 static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
@@ -545,6 +557,7 @@ void init_revisions(struct rev_info *revs, const char *prefix)
 	revs->ignore_merges = 1;
 	revs->simplify_history = 1;
 	revs->pruning.recursive = 1;
+	revs->pruning.quiet = 1;
 	revs->pruning.add_remove = file_add_remove;
 	revs->pruning.change = file_change;
 	revs->lifo = 1;
diff --git a/run-command.c b/run-command.c
index bef9775e08..eff523e191 100644
--- a/run-command.c
+++ b/run-command.c
@@ -8,11 +8,19 @@ static inline void close_pair(int fd[2])
 	close(fd[1]);
 }
 
+static inline void dup_devnull(int to)
+{
+	int fd = open("/dev/null", O_RDWR);
+	dup2(fd, to);
+	close(fd);
+}
+
 int start_command(struct child_process *cmd)
 {
-	int need_in = !cmd->no_stdin && cmd->in < 0;
-	int fdin[2];
+	int need_in, need_out;
+	int fdin[2], fdout[2];
 
+	need_in = !cmd->no_stdin && cmd->in < 0;
 	if (need_in) {
 		if (pipe(fdin) < 0)
 			return -ERR_RUN_COMMAND_PIPE;
@@ -20,19 +28,32 @@ int start_command(struct child_process *cmd)
 		cmd->close_in = 1;
 	}
 
+	need_out = !cmd->no_stdout
+		&& !cmd->stdout_to_stderr
+		&& cmd->out < 0;
+	if (need_out) {
+		if (pipe(fdout) < 0) {
+			if (need_in)
+				close_pair(fdin);
+			return -ERR_RUN_COMMAND_PIPE;
+		}
+		cmd->out = fdout[0];
+		cmd->close_out = 1;
+	}
+
 	cmd->pid = fork();
 	if (cmd->pid < 0) {
 		if (need_in)
 			close_pair(fdin);
+		if (need_out)
+			close_pair(fdout);
 		return -ERR_RUN_COMMAND_FORK;
 	}
 
 	if (!cmd->pid) {
-		if (cmd->no_stdin) {
-			int fd = open("/dev/null", O_RDWR);
-			dup2(fd, 0);
-			close(fd);
-		} else if (need_in) {
+		if (cmd->no_stdin)
+			dup_devnull(0);
+		else if (need_in) {
 			dup2(fdin[0], 0);
 			close_pair(fdin);
 		} else if (cmd->in) {
@@ -40,8 +61,18 @@ int start_command(struct child_process *cmd)
 			close(cmd->in);
 		}
 
-		if (cmd->stdout_to_stderr)
+		if (cmd->no_stdout)
+			dup_devnull(1);
+		else if (cmd->stdout_to_stderr)
 			dup2(2, 1);
+		else if (need_out) {
+			dup2(fdout[1], 1);
+			close_pair(fdout);
+		} else if (cmd->out > 1) {
+			dup2(cmd->out, 1);
+			close(cmd->out);
+		}
+
 		if (cmd->git_cmd) {
 			execv_git_cmd(cmd->argv);
 		} else {
@@ -55,6 +86,11 @@ int start_command(struct child_process *cmd)
 	else if (cmd->in)
 		close(cmd->in);
 
+	if (need_out)
+		close(fdout[1]);
+	else if (cmd->out > 1)
+		close(cmd->out);
+
 	return 0;
 }
 
@@ -62,6 +98,8 @@ int finish_command(struct child_process *cmd)
 {
 	if (cmd->close_in)
 		close(cmd->in);
+	if (cmd->close_out)
+		close(cmd->out);
 
 	for (;;) {
 		int status, code;
diff --git a/run-command.h b/run-command.h
index ff090679a6..3680ef9d45 100644
--- a/run-command.h
+++ b/run-command.h
@@ -15,8 +15,11 @@ struct child_process {
 	const char **argv;
 	pid_t pid;
 	int in;
+	int out;
 	unsigned close_in:1;
+	unsigned close_out:1;
 	unsigned no_stdin:1;
+	unsigned no_stdout:1;
 	unsigned git_cmd:1; /* if this is to be git sub-command */
 	unsigned stdout_to_stderr:1;
 };
diff --git a/send-pack.c b/send-pack.c
index 512b660e99..d5b51628df 100644
--- a/send-pack.c
+++ b/send-pack.c
@@ -3,7 +3,7 @@
 #include "tag.h"
 #include "refs.h"
 #include "pkt-line.h"
-#include "exec_cmd.h"
+#include "run-command.h"
 
 static const char send_pack_usage[] =
 "git-send-pack [--all] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
@@ -19,46 +19,35 @@ static int use_thin_pack;
  */
 static int pack_objects(int fd, struct ref *refs)
 {
-	int pipe_fd[2];
-	pid_t pid;
-
-	if (pipe(pipe_fd) < 0)
-		return error("send-pack: pipe failed");
-	pid = fork();
-	if (pid < 0)
-		return error("send-pack: unable to fork git-pack-objects");
-	if (!pid) {
-		/*
-		 * The child becomes pack-objects --revs; we feed
-		 * the revision parameters to it via its stdin and
-		 * let its stdout go back to the other end.
-		 */
-		static const char *args[] = {
-			"pack-objects",
-			"--all-progress",
-			"--revs",
-			"--stdout",
-			NULL,
-			NULL,
-		};
-		if (use_thin_pack)
-			args[4] = "--thin";
-		dup2(pipe_fd[0], 0);
-		dup2(fd, 1);
-		close(pipe_fd[0]);
-		close(pipe_fd[1]);
-		close(fd);
-		execv_git_cmd(args);
-		die("git-pack-objects exec failed (%s)", strerror(errno));
-	}
+	/*
+	 * The child becomes pack-objects --revs; we feed
+	 * the revision parameters to it via its stdin and
+	 * let its stdout go back to the other end.
+	 */
+	const char *args[] = {
+		"pack-objects",
+		"--all-progress",
+		"--revs",
+		"--stdout",
+		NULL,
+		NULL,
+	};
+	struct child_process po;
+
+	if (use_thin_pack)
+		args[4] = "--thin";
+	memset(&po, 0, sizeof(po));
+	po.argv = args;
+	po.in = -1;
+	po.out = fd;
+	po.git_cmd = 1;
+	if (start_command(&po))
+		die("git-pack-objects failed (%s)", strerror(errno));
 
 	/*
 	 * We feed the pack-objects we just spawned with revision
 	 * parameters by writing to the pipe.
 	 */
-	close(pipe_fd[0]);
-	close(fd);
-
 	while (refs) {
 		char buf[42];
 
@@ -67,38 +56,23 @@ static int pack_objects(int fd, struct ref *refs)
 			memcpy(buf + 1, sha1_to_hex(refs->old_sha1), 40);
 			buf[0] = '^';
 			buf[41] = '\n';
-			if (!write_or_whine(pipe_fd[1], buf, 42,
+			if (!write_or_whine(po.in, buf, 42,
 						"send-pack: send refs"))
 				break;
 		}
 		if (!is_null_sha1(refs->new_sha1)) {
 			memcpy(buf, sha1_to_hex(refs->new_sha1), 40);
 			buf[40] = '\n';
-			if (!write_or_whine(pipe_fd[1], buf, 41,
+			if (!write_or_whine(po.in, buf, 41,
 						"send-pack: send refs"))
 				break;
 		}
 		refs = refs->next;
 	}
-	close(pipe_fd[1]);
-
-	for (;;) {
-		int status, code;
-		pid_t waiting = waitpid(pid, &status, 0);
 
-		if (waiting < 0) {
-			if (errno == EINTR)
-				continue;
-			return error("waitpid failed (%s)", strerror(errno));
-		}
-		if ((waiting != pid) || WIFSIGNALED(status) ||
-		    !WIFEXITED(status))
-			return error("pack-objects died with strange error");
-		code = WEXITSTATUS(status);
-		if (code)
-			return -code;
-		return 0;
-	}
+	if (finish_command(&po))
+		return error("pack-objects died with strange error");
+	return 0;
 }
 
 static void unmark_and_free(struct commit_list *list, unsigned int mark)
diff --git a/sha1_file.c b/sha1_file.c
index 110d696213..b0b21776e7 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1352,6 +1352,87 @@ static void *unpack_compressed_entry(struct packed_git *p,
 	return buffer;
 }
 
+#define MAX_DELTA_CACHE (256)
+
+static size_t delta_base_cached;
+static struct delta_base_cache_entry {
+	struct packed_git *p;
+	off_t base_offset;
+	unsigned long size;
+	void *data;
+	enum object_type type;
+} delta_base_cache[MAX_DELTA_CACHE];
+
+static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
+{
+	unsigned long hash;
+
+	hash = (unsigned long)p + (unsigned long)base_offset;
+	hash += (hash >> 8) + (hash >> 16);
+	return hash & 0xff;
+}
+
+static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
+	unsigned long *base_size, enum object_type *type, int keep_cache)
+{
+	void *ret;
+	unsigned long hash = pack_entry_hash(p, base_offset);
+	struct delta_base_cache_entry *ent = delta_base_cache + hash;
+
+	ret = ent->data;
+	if (ret && ent->p == p && ent->base_offset == base_offset)
+		goto found_cache_entry;
+	return unpack_entry(p, base_offset, type, base_size);
+
+found_cache_entry:
+	if (!keep_cache) {
+		ent->data = NULL;
+		delta_base_cached -= ent->size;
+	}
+	else {
+		ret = xmalloc(ent->size + 1);
+		memcpy(ret, ent->data, ent->size);
+		((char *)ret)[ent->size] = 0;
+	}
+	*type = ent->type;
+	*base_size = ent->size;
+	return ret;
+}
+
+static inline void release_delta_base_cache(struct delta_base_cache_entry *ent)
+{
+	if (ent->data) {
+		free(ent->data);
+		ent->data = NULL;
+		delta_base_cached -= ent->size;
+	}
+}
+
+static void add_delta_base_cache(struct packed_git *p, off_t base_offset,
+	void *base, unsigned long base_size, enum object_type type)
+{
+	unsigned long i, hash = pack_entry_hash(p, base_offset);
+	struct delta_base_cache_entry *ent = delta_base_cache + hash;
+
+	release_delta_base_cache(ent);
+	delta_base_cached += base_size;
+	for (i = 0; delta_base_cached > delta_base_cache_limit
+		&& i < ARRAY_SIZE(delta_base_cache); i++) {
+		struct delta_base_cache_entry *f = delta_base_cache + i;
+		if (f->type == OBJ_BLOB)
+			release_delta_base_cache(f);
+	}
+	for (i = 0; delta_base_cached > delta_base_cache_limit
+		&& i < ARRAY_SIZE(delta_base_cache); i++)
+		release_delta_base_cache(delta_base_cache + i);
+
+	ent->p = p;
+	ent->base_offset = base_offset;
+	ent->type = type;
+	ent->data = base;
+	ent->size = base_size;
+}
+
 static void *unpack_delta_entry(struct packed_git *p,
 				struct pack_window **w_curs,
 				off_t curpos,
@@ -1365,7 +1446,7 @@ static void *unpack_delta_entry(struct packed_git *p,
 	off_t base_offset;
 
 	base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
-	base = unpack_entry(p, base_offset, type, &base_size);
+	base = cache_or_unpack_entry(p, base_offset, &base_size, type, 0);
 	if (!base)
 		die("failed to read delta base object"
 		    " at %"PRIuMAX" from %s",
@@ -1378,7 +1459,7 @@ static void *unpack_delta_entry(struct packed_git *p,
 	if (!result)
 		die("failed to apply delta");
 	free(delta_data);
-	free(base);
+	add_delta_base_cache(p, base_offset, base, base_size, *type);
 	return result;
 }
 
@@ -1562,7 +1643,7 @@ static void *read_packed_sha1(const unsigned char *sha1,
 	if (!find_pack_entry(sha1, &e, NULL))
 		return NULL;
 	else
-		return unpack_entry(e.p, e.offset, type, size);
+		return cache_or_unpack_entry(e.p, e.offset, size, type, 1);
 }
 
 /*
diff --git a/t/t4017-diff-retval.sh b/t/t4017-diff-retval.sh
new file mode 100755
index 0000000000..68731908be
--- /dev/null
+++ b/t/t4017-diff-retval.sh
@@ -0,0 +1,79 @@
+#!/bin/sh
+
+test_description='Return value of diffs'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	echo 1 >a &&
+	git add . &&
+	git commit -m first &&
+	echo 2 >b &&
+	git add . &&
+	git commit -a -m second
+'
+
+test_expect_success 'git diff-tree HEAD^ HEAD' '
+	git diff-tree --exit-code HEAD^ HEAD
+	test $? = 1
+'
+test_expect_success 'git diff-tree HEAD^ HEAD -- a' '
+	git diff-tree --exit-code HEAD^ HEAD -- a
+	test $? = 0
+'
+test_expect_success 'git diff-tree HEAD^ HEAD -- b' '
+	git diff-tree --exit-code HEAD^ HEAD -- b
+	test $? = 1
+'
+test_expect_success 'echo HEAD | git diff-tree --stdin' '
+	echo $(git rev-parse HEAD) | git diff-tree --exit-code --stdin
+	test $? = 1
+'
+test_expect_success 'git diff-tree HEAD HEAD' '
+	git diff-tree --exit-code HEAD HEAD
+	test $? = 0
+'
+test_expect_success 'git diff-files' '
+	git diff-files --exit-code
+	test $? = 0
+'
+test_expect_success 'git diff-index --cached HEAD' '
+	git diff-index --exit-code --cached HEAD
+	test $? = 0
+'
+test_expect_success 'git diff-index --cached HEAD^' '
+	git diff-index --exit-code --cached HEAD^
+	test $? = 1
+'
+test_expect_success 'git diff-index --cached HEAD^' '
+	echo text >>b &&
+	echo 3 >c &&
+	git add . && {
+		git diff-index --exit-code --cached HEAD^
+		test $? = 1
+	}
+'
+test_expect_success 'git diff-tree -Stext HEAD^ HEAD -- b' '
+	git commit -m "text in b" && {
+		git diff-tree -p --exit-code -Stext HEAD^ HEAD -- b
+		test $? = 1
+	}
+'
+test_expect_success 'git diff-tree -Snot-found HEAD^ HEAD -- b' '
+	git diff-tree -p --exit-code -Snot-found HEAD^ HEAD -- b
+	test $? = 0
+'
+test_expect_success 'git diff-files' '
+	echo 3 >>c && {
+		git diff-files --exit-code
+		test $? = 1
+	}
+'
+test_expect_success 'git diff-index --cached HEAD' '
+	git update-index c && {
+		git diff-index --exit-code --cached HEAD
+		test $? = 1
+	}
+'
+
+test_done
diff --git a/t/t4017-quiet.sh b/t/t4017-quiet.sh
new file mode 100755
index 0000000000..e747e84227
--- /dev/null
+++ b/t/t4017-quiet.sh
@@ -0,0 +1,80 @@
+#!/bin/sh
+
+test_description='Return value of diffs'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	echo 1 >a &&
+	git add . &&
+	git commit -m first &&
+	echo 2 >b &&
+	git add . &&
+	git commit -a -m second
+'
+
+test_expect_success 'git diff-tree HEAD^ HEAD' '
+	git diff-tree --quiet HEAD^ HEAD >cnt
+	test $? = 1 && test $(wc -l <cnt) = 0
+'
+test_expect_success 'git diff-tree HEAD^ HEAD -- a' '
+	git diff-tree --quiet HEAD^ HEAD -- a >cnt
+	test $? = 0 && test $(wc -l <cnt) = 0
+'
+test_expect_success 'git diff-tree HEAD^ HEAD -- b' '
+	git diff-tree --quiet HEAD^ HEAD -- b >cnt
+	test $? = 1 && test $(wc -l <cnt) = 0
+'
+# this diff outputs one line: sha1 of the given head
+test_expect_success 'echo HEAD | git diff-tree --stdin' '
+	echo $(git rev-parse HEAD) | git diff-tree --quiet --stdin >cnt
+	test $? = 1 && test $(wc -l <cnt) = 1
+'
+test_expect_success 'git diff-tree HEAD HEAD' '
+	git diff-tree --quiet HEAD HEAD >cnt
+	test $? = 0 && test $(wc -l <cnt) = 0
+'
+test_expect_success 'git diff-files' '
+	git diff-files --quiet >cnt
+	test $? = 0 && test $(wc -l <cnt) = 0
+'
+test_expect_success 'git diff-index --cached HEAD' '
+	git diff-index --quiet --cached HEAD >cnt
+	test $? = 0 && test $(wc -l <cnt) = 0
+'
+test_expect_success 'git diff-index --cached HEAD^' '
+	git diff-index --quiet --cached HEAD^ >cnt
+	test $? = 1 && test $(wc -l <cnt) = 0
+'
+test_expect_success 'git diff-index --cached HEAD^' '
+	echo text >>b &&
+	echo 3 >c &&
+	git add . && {
+		git diff-index --quiet --cached HEAD^ >cnt
+		test $? = 1 && test $(wc -l <cnt) = 0
+	}
+'
+test_expect_success 'git diff-tree -Stext HEAD^ HEAD -- b' '
+	git commit -m "text in b" && {
+		git diff-tree --quiet -Stext HEAD^ HEAD -- b >cnt
+		test $? = 1 && test $(wc -l <cnt) = 0
+	}
+'
+test_expect_success 'git diff-tree -Snot-found HEAD^ HEAD -- b' '
+	git diff-tree --quiet -Snot-found HEAD^ HEAD -- b >cnt
+	test $? = 0 && test $(wc -l <cnt) = 0
+'
+test_expect_success 'git diff-files' '
+	echo 3 >>c && {
+		git diff-files --quiet >cnt
+		test $? = 1 && test $(wc -l <cnt) = 0
+	}
+'
+test_expect_success 'git diff-index --cached HEAD' '
+	git update-index c && {
+		git diff-index --quiet --cached HEAD >cnt
+		test $? = 1 && test $(wc -l <cnt) = 0
+	}
+'
+
+test_done
diff --git a/tree-diff.c b/tree-diff.c
index c8275823d0..3940962e79 100644
--- a/tree-diff.c
+++ b/tree-diff.c
@@ -5,9 +5,8 @@
 #include "diff.h"
 #include "tree.h"
 
-static char *malloc_base(const char *base, const char *path, int pathlen)
+static char *malloc_base(const char *base, int baselen, const char *path, int pathlen)
 {
-	int baselen = strlen(base);
 	char *newbase = xmalloc(baselen + pathlen + 2);
 	memcpy(newbase, base, baselen);
 	memcpy(newbase + baselen, path, pathlen);
@@ -16,9 +15,9 @@ static char *malloc_base(const char *base, const char *path, int pathlen)
 }
 
 static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc,
-		       const char *base);
+		       const char *base, int baselen);
 
-static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const char *base, struct diff_options *opt)
+static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const char *base, int baselen, struct diff_options *opt)
 {
 	unsigned mode1, mode2;
 	const char *path1, *path2;
@@ -28,15 +27,15 @@ static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const
 	sha1 = tree_entry_extract(t1, &path1, &mode1);
 	sha2 = tree_entry_extract(t2, &path2, &mode2);
 
-	pathlen1 = strlen(path1);
-	pathlen2 = strlen(path2);
+	pathlen1 = tree_entry_len(path1, sha1);
+	pathlen2 = tree_entry_len(path2, sha2);
 	cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
 	if (cmp < 0) {
-		show_entry(opt, "-", t1, base);
+		show_entry(opt, "-", t1, base, baselen);
 		return -1;
 	}
 	if (cmp > 0) {
-		show_entry(opt, "+", t2, base);
+		show_entry(opt, "+", t2, base, baselen);
 		return 1;
 	}
 	if (!opt->find_copies_harder && !hashcmp(sha1, sha2) && mode1 == mode2)
@@ -47,14 +46,14 @@ static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const
 	 * file, we need to consider it a remove and an add.
 	 */
 	if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
-		show_entry(opt, "-", t1, base);
-		show_entry(opt, "+", t2, base);
+		show_entry(opt, "-", t1, base, baselen);
+		show_entry(opt, "+", t2, base, baselen);
 		return 0;
 	}
 
 	if (opt->recursive && S_ISDIR(mode1)) {
 		int retval;
-		char *newbase = malloc_base(base, path1, pathlen1);
+		char *newbase = malloc_base(base, baselen, path1, pathlen1);
 		if (opt->tree_in_recursive)
 			opt->change(opt, mode1, mode2,
 				    sha1, sha2, base, path1);
@@ -67,20 +66,20 @@ static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const
 	return 0;
 }
 
-static int interesting(struct tree_desc *desc, const char *base, struct diff_options *opt)
+static int interesting(struct tree_desc *desc, const char *base, int baselen, struct diff_options *opt)
 {
 	const char *path;
+	const unsigned char *sha1;
 	unsigned mode;
 	int i;
-	int baselen, pathlen;
+	int pathlen;
 
 	if (!opt->nr_paths)
 		return 1;
 
-	(void)tree_entry_extract(desc, &path, &mode);
+	sha1 = tree_entry_extract(desc, &path, &mode);
 
-	pathlen = strlen(path);
-	baselen = strlen(base);
+	pathlen = tree_entry_len(path, sha1);
 
 	for (i=0; i < opt->nr_paths; i++) {
 		const char *match = opt->paths[i];
@@ -121,18 +120,18 @@ static int interesting(struct tree_desc *desc, const char *base, struct diff_opt
 }
 
 /* A whole sub-tree went away or appeared */
-static void show_tree(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base)
+static void show_tree(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base, int baselen)
 {
 	while (desc->size) {
-		if (interesting(desc, base, opt))
-			show_entry(opt, prefix, desc, base);
+		if (interesting(desc, base, baselen, opt))
+			show_entry(opt, prefix, desc, base, baselen);
 		update_tree_entry(desc);
 	}
 }
 
 /* A file entry went away or appeared */
 static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc,
-		       const char *base)
+		       const char *base, int baselen)
 {
 	unsigned mode;
 	const char *path;
@@ -140,7 +139,8 @@ static void show_entry(struct diff_options *opt, const char *prefix, struct tree
 
 	if (opt->recursive && S_ISDIR(mode)) {
 		enum object_type type;
-		char *newbase = malloc_base(base, path, strlen(path));
+		int pathlen = tree_entry_len(path, sha1);
+		char *newbase = malloc_base(base, baselen, path, pathlen);
 		struct tree_desc inner;
 		void *tree;
 
@@ -149,7 +149,7 @@ static void show_entry(struct diff_options *opt, const char *prefix, struct tree
 			die("corrupt tree sha %s", sha1_to_hex(sha1));
 
 		inner.buf = tree;
-		show_tree(opt, prefix, &inner, newbase);
+		show_tree(opt, prefix, &inner, newbase, baselen + 1 + pathlen);
 
 		free(tree);
 		free(newbase);
@@ -160,26 +160,30 @@ static void show_entry(struct diff_options *opt, const char *prefix, struct tree
 
 int diff_tree(struct tree_desc *t1, struct tree_desc *t2, const char *base, struct diff_options *opt)
 {
+	int baselen = strlen(base);
+
 	while (t1->size | t2->size) {
-		if (opt->nr_paths && t1->size && !interesting(t1, base, opt)) {
+		if (opt->quiet && opt->has_changes)
+			break;
+		if (opt->nr_paths && t1->size && !interesting(t1, base, baselen, opt)) {
 			update_tree_entry(t1);
 			continue;
 		}
-		if (opt->nr_paths && t2->size && !interesting(t2, base, opt)) {
+		if (opt->nr_paths && t2->size && !interesting(t2, base, baselen, opt)) {
 			update_tree_entry(t2);
 			continue;
 		}
 		if (!t1->size) {
-			show_entry(opt, "+", t2, base);
+			show_entry(opt, "+", t2, base, baselen);
 			update_tree_entry(t2);
 			continue;
 		}
 		if (!t2->size) {
-			show_entry(opt, "-", t1, base);
+			show_entry(opt, "-", t1, base, baselen);
 			update_tree_entry(t1);
 			continue;
 		}
-		switch (compare_tree_entry(t1, t2, base, opt)) {
+		switch (compare_tree_entry(t1, t2, base, baselen, opt)) {
 		case -1:
 			update_tree_entry(t1);
 			continue;
diff --git a/tree-walk.c b/tree-walk.c
index 70f899957e..a4a4e2a989 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -32,7 +32,7 @@ static void entry_clear(struct name_entry *a)
 static void entry_extract(struct tree_desc *t, struct name_entry *a)
 {
 	a->sha1 = tree_entry_extract(t, &a->path, &a->mode);
-	a->pathlen = strlen(a->path);
+	a->pathlen = tree_entry_len(a->path, a->sha1);
 }
 
 void update_tree_entry(struct tree_desc *desc)
@@ -169,7 +169,7 @@ static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char
 
 		sha1 = tree_entry_extract(t, &entry, mode);
 		update_tree_entry(t);
-		entrylen = strlen(entry);
+		entrylen = tree_entry_len(entry, sha1);
 		if (entrylen > namelen)
 			continue;
 		cmp = memcmp(name, entry, entrylen);
diff --git a/tree-walk.h b/tree-walk.h
index e57befa4da..a0d7afd89b 100644
--- a/tree-walk.h
+++ b/tree-walk.h
@@ -13,6 +13,11 @@ struct name_entry {
 	int pathlen;
 };
 
+static inline int tree_entry_len(const char *name, const unsigned char *sha1)
+{
+	return (char *)sha1 - (char *)name - 1;
+}
+
 void update_tree_entry(struct tree_desc *);
 const unsigned char *tree_entry_extract(struct tree_desc *, const char **, unsigned int *);