Merge branch 'master' into js/shallow
authorJunio C Hamano <junkio@cox.net>
Wed, 27 Dec 2006 10:43:46 +0000 (02:43 -0800)
committerJunio C Hamano <junkio@cox.net>
Wed, 27 Dec 2006 10:43:46 +0000 (02:43 -0800)
This is to adjust to:

count-objects -v: show number of packs as well.

which will break a test in this series.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Makefile
commit.c
commit.h
fetch-pack.c
git-clone.sh
git-fetch.sh
shallow.c [new file with mode: 0644]
t/t5500-fetch-pack.sh
upload-pack.c
index 52d4a3a86a214a99bd3cf32053539e18f36778a7..c21b91bfab2e8665be728593c64352137c857fd4 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -250,8 +250,7 @@ LIB_OBJS = \
        revision.o pager.o tree-walk.o xdiff-interface.o \
        write_or_die.o trace.o list-objects.o grep.o \
        alloc.o merge-file.o path-list.o help.o unpack-trees.o $(DIFF_OBJS) \
-       color.o wt-status.o archive-zip.o archive-tar.o \
-       utf8.o
+       color.o wt-status.o archive-zip.o archive-tar.o shallow.o utf8.o
 
 BUILTIN_OBJS = \
        builtin-add.o \
index 3167ce62acd5eb1076a4c089b54f2b37f821130b..59ea77c577886a3ba5b4ef385099d7a564af173c 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "tag.h"
 #include "commit.h"
+#include "pkt-line.h"
 
 int save_commit_buffer = 1;
 
@@ -221,6 +222,8 @@ static void prepare_commit_graft(void)
                return;
        graft_file = get_graft_file();
        read_graft_file(graft_file);
+       /* make sure shallows are read */
+       is_repository_shallow();
        commit_graft_prepared = 1;
 }
 
@@ -234,6 +237,37 @@ static struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
        return commit_graft[pos];
 }
 
+int write_shallow_commits(int fd, int use_pack_protocol)
+{
+       int i, count = 0;
+       for (i = 0; i < commit_graft_nr; i++)
+               if (commit_graft[i]->nr_parent < 0) {
+                       const char *hex =
+                               sha1_to_hex(commit_graft[i]->sha1);
+                       count++;
+                       if (use_pack_protocol)
+                               packet_write(fd, "shallow %s", hex);
+                       else {
+                               write(fd, hex,  40);
+                               write(fd, "\n", 1);
+                       }
+               }
+       return count;
+}
+
+int unregister_shallow(const unsigned char *sha1)
+{
+       int pos = commit_graft_pos(sha1);
+       if (pos < 0)
+               return -1;
+       if (pos + 1 < commit_graft_nr)
+               memcpy(commit_graft + pos, commit_graft + pos + 1,
+                               sizeof(struct commit_graft *)
+                               * (commit_graft_nr - pos - 1));
+       commit_graft_nr--;
+       return 0;
+}
+
 int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
 {
        char *tail = buffer;
index 10eea9f26ff5db9df82245756c9c8bff0f6be3f6..936f8fce301672b5b78352a217403cc319ab3f07 100644 (file)
--- a/commit.h
+++ b/commit.h
@@ -97,7 +97,7 @@ void sort_in_topological_order_fn(struct commit_list ** list, int lifo,
 
 struct commit_graft {
        unsigned char sha1[20];
-       int nr_parent;
+       int nr_parent; /* < 0 if shallow commit */
        unsigned char parent[FLEX_ARRAY][20]; /* more */
 };
 
@@ -107,5 +107,12 @@ int read_graft_file(const char *graft_file);
 
 extern struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2, int cleanup);
 
+extern int register_shallow(const unsigned char *sha1);
+extern int unregister_shallow(const unsigned char *sha1);
+extern int write_shallow_commits(int fd, int use_pack_protocol);
+extern int is_repository_shallow();
+extern struct commit_list *get_shallow_commits(struct object_array *heads,
+               int depth, int shallow_flag, int not_shallow_flag);
+
 int in_merge_bases(struct commit *rev1, struct commit *rev2);
 #endif /* COMMIT_H */
index 92322cf4da39434d44e4aa52fa0c3f735b22d752..c527bf9e9621519f72e1039313666a03ee12c586 100644 (file)
@@ -10,8 +10,9 @@ static int keep_pack;
 static int quiet;
 static int verbose;
 static int fetch_all;
+static int depth;
 static const char fetch_pack_usage[] =
-"git-fetch-pack [--all] [-q] [-v] [-k] [--thin] [--exec=upload-pack] [host:]directory <refs>...";
+"git-fetch-pack [--all] [-q] [-v] [-k] [--thin] [--exec=upload-pack] [--depth=<n>] [host:]directory <refs>...";
 static const char *exec = "git-upload-pack";
 
 #define COMPLETE       (1U << 0)
@@ -179,10 +180,41 @@ static int find_common(int fd[2], unsigned char *result_sha1,
                        packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
                fetching++;
        }
+       if (is_repository_shallow())
+               write_shallow_commits(fd[1], 1);
+       if (depth > 0)
+               packet_write(fd[1], "deepen %d", depth);
        packet_flush(fd[1]);
        if (!fetching)
                return 1;
 
+       if (depth > 0) {
+               char line[1024];
+               unsigned char sha1[20];
+               int len;
+
+               while ((len = packet_read_line(fd[0], line, sizeof(line)))) {
+                       if (!strncmp("shallow ", line, 8)) {
+                               if (get_sha1_hex(line + 8, sha1))
+                                       die("invalid shallow line: %s", line);
+                               register_shallow(sha1);
+                               continue;
+                       }
+                       if (!strncmp("unshallow ", line, 10)) {
+                               if (get_sha1_hex(line + 10, sha1))
+                                       die("invalid unshallow line: %s", line);
+                               if (!lookup_object(sha1))
+                                       die("object not found: %s", line);
+                               /* make sure that it is parsed as shallow */
+                               parse_object(sha1);
+                               if (unregister_shallow(sha1))
+                                       die("no shallow found: %s", line);
+                               continue;
+                       }
+                       die("expected shallow/unshallow, got %s", line);
+               }
+       }
+
        flushes = 0;
        retval = -1;
        while ((sha1 = get_rev())) {
@@ -309,7 +341,8 @@ static void filter_refs(struct ref **refs, int nr_match, char **match)
                if (!memcmp(ref->name, "refs/", 5) &&
                    check_ref_format(ref->name + 5))
                        ; /* trash */
-               else if (fetch_all) {
+               else if (fetch_all &&
+                        (!depth || strncmp(ref->name, "refs/tags/", 10) )) {
                        *newtail = ref;
                        ref->next = NULL;
                        newtail = &ref->next;
@@ -368,9 +401,11 @@ static int everything_local(struct ref **refs, int nr_match, char **match)
                }
        }
 
-       for_each_ref(mark_complete, NULL);
-       if (cutoff)
-               mark_recent_complete_commits(cutoff);
+       if (!depth) {
+               for_each_ref(mark_complete, NULL);
+               if (cutoff)
+                       mark_recent_complete_commits(cutoff);
+       }
 
        /*
         * Mark all complete remote refs as common refs.
@@ -522,6 +557,8 @@ static int fetch_pack(int fd[2], int nr_match, char **match)
        int status;
 
        get_remote_heads(fd[0], &ref, 0, NULL, 0);
+       if (is_repository_shallow() && !server_supports("shallow"))
+               die("Server does not support shallow clients");
        if (server_supports("multi_ack")) {
                if (verbose)
                        fprintf(stderr, "Server supports multi_ack\n");
@@ -594,6 +631,8 @@ int main(int argc, char **argv)
        char *dest = NULL, **heads;
        int fd[2];
        pid_t pid;
+       struct stat st;
+       struct lock_file lock;
 
        setup_git_directory();
 
@@ -627,6 +666,12 @@ int main(int argc, char **argv)
                                verbose = 1;
                                continue;
                        }
+                       if (!strncmp("--depth=", arg, 8)) {
+                               depth = strtol(arg + 8, NULL, 0);
+                               if (stat(git_path("shallow"), &st))
+                                       st.st_mtime = 0;
+                               continue;
+                       }
                        usage(fetch_pack_usage);
                }
                dest = arg;
@@ -659,5 +704,34 @@ int main(int argc, char **argv)
                        }
        }
 
+       if (!ret && depth > 0) {
+               struct cache_time mtime;
+               char *shallow = git_path("shallow");
+               int fd;
+
+               mtime.sec = st.st_mtime;
+#ifdef USE_NSEC
+               mtime.usec = st.st_mtim.usec;
+#endif
+               if (stat(shallow, &st)) {
+                       if (mtime.sec)
+                               die("shallow file was removed during fetch");
+               } else if (st.st_mtime != mtime.sec
+#ifdef USE_NSEC
+                               || st.st_mtim.usec != mtime.usec
+#endif
+                         )
+                       die("shallow file was changed during fetch");
+
+               fd = hold_lock_file_for_update(&lock, shallow, 1);
+               if (!write_shallow_commits(fd, 0)) {
+                       unlink(shallow);
+                       rollback_lock_file(&lock);
+               } else {
+                       close(fd);
+                       commit_lock_file(&lock);
+               }
+       }
+
        return !!ret;
 }
index 490f3e48db02d01cb480047c011aa7b670c431bc..f37eb9d105264294e1dd63beaeb192023a0ec8c6 100755 (executable)
@@ -14,7 +14,7 @@ die() {
 }
 
 usage() {
-       die "Usage: $0 [--template=<template_directory>] [--reference <reference-repo>] [--bare] [-l [-s]] [-q] [-u <upload-pack>] [--origin <name>] [-n] <repo> [<dir>]"
+       die "Usage: $0 [--template=<template_directory>] [--reference <reference-repo>] [--bare] [-l [-s]] [-q] [-u <upload-pack>] [--origin <name>] [--depth <n>] [-n] <repo> [<dir>]"
 }
 
 get_repo_base() {
@@ -120,6 +120,7 @@ reference=
 origin=
 origin_override=
 use_separate_remote=t
+depth=
 while
        case "$#,$1" in
        0,*) break ;;
@@ -163,6 +164,10 @@ while
        *,-u|*,--upload-pack)
                shift
                upload_pack="--exec=$1" ;;
+       1,--depth) usage;;
+       *,--depth)
+               shift
+               depth="--depth=$1";;
        *,-*) usage ;;
        *) break ;;
        esac
@@ -267,6 +272,10 @@ yes,yes)
 *)
        case "$repo" in
        rsync://*)
+               case "$depth" in
+               "") ;;
+               *) die "shallow over rsync not supported" ;;
+               esac
                rsync $quiet -av --ignore-existing  \
                        --exclude info "$repo/objects/" "$GIT_DIR/objects/" ||
                exit
@@ -295,6 +304,10 @@ yes,yes)
                git-ls-remote "$repo" >"$GIT_DIR/CLONE_HEAD" || exit 1
                ;;
        https://*|http://*|ftp://*)
+               case "$depth" in
+               "") ;;
+               *) die "shallow over http or ftp not supported" ;;
+               esac
                if test -z "@@NO_CURL@@"
                then
                        clone_dumb_http "$repo" "$D"
@@ -304,8 +317,8 @@ yes,yes)
                ;;
        *)
                case "$upload_pack" in
-               '') git-fetch-pack --all -k $quiet "$repo" ;;
-               *) git-fetch-pack --all -k $quiet "$upload_pack" "$repo" ;;
+               '') git-fetch-pack --all -k $quiet $depth "$repo" ;;
+               *) git-fetch-pack --all -k $quiet "$upload_pack" $depth "$repo" ;;
                esac >"$GIT_DIR/CLONE_HEAD" ||
                        die "fetch-pack from '$repo' failed."
                ;;
index ffbd44f0e1ab841e6f6a38295860220b01bb26ea..5f316053fb9ad146546ed0718cc98b772c48b07f 100755 (executable)
@@ -27,6 +27,7 @@ update_head_ok=
 exec=
 upload_pack=
 keep=
+shallow_depth=
 while case "$#" in 0) break ;; esac
 do
        case "$1" in
@@ -62,6 +63,13 @@ do
        --reflog-action=*)
                rloga=`expr "z$1" : 'z-[^=]*=\(.*\)'`
                ;;
+       --depth=*)
+               shallow_depth="--depth=`expr "z$1" : 'z-[^=]*=\(.*\)'`"
+               ;;
+       --depth)
+               shift
+               shallow_depth="--depth=$1"
+               ;;
        -*)
                usage
                ;;
@@ -305,6 +313,8 @@ fetch_main () {
       # There are transports that can fetch only one head at a time...
       case "$remote" in
       http://* | https://* | ftp://*)
+         test -n "$shallow_depth" &&
+               die "shallow clone with http not supported"
          proto=`expr "$remote" : '\([^:]*\):'`
          if [ -n "$GIT_SSL_NO_VERIFY" ]; then
              curl_extra_args="-k"
@@ -331,6 +341,8 @@ fetch_main () {
          git-http-fetch -v -a "$head" "$remote/" || exit
          ;;
       rsync://*)
+         test -n "$shallow_depth" &&
+               die "shallow clone with rsync not supported"
          TMP_HEAD="$GIT_DIR/TMP_HEAD"
          rsync -L -q "$remote/$remote_name" "$TMP_HEAD" || exit 1
          head=$(git-rev-parse --verify TMP_HEAD)
@@ -378,7 +390,7 @@ fetch_main () {
       pack_lockfile=
       IFS="    $LF"
       (
-         git-fetch-pack --thin $exec $keep "$remote" $rref || echo failed "$remote"
+         git-fetch-pack --thin $exec $keep $shallow_depth "$remote" $rref || echo failed "$remote"
       ) |
       while read sha1 remote_name
       do
@@ -451,6 +463,8 @@ case "$no_tags$tags" in
        case "$taglist" in
        '') ;;
        ?*)
+               # do not deepen a shallow tree when following tags
+               shallow_depth=
                fetch_main "$taglist" || exit ;;
        esac
 esac
diff --git a/shallow.c b/shallow.c
new file mode 100644 (file)
index 0000000..3d53d17
--- /dev/null
+++ b/shallow.c
@@ -0,0 +1,104 @@
+#include "cache.h"
+#include "commit.h"
+#include "tag.h"
+
+static int is_shallow = -1;
+
+int register_shallow(const unsigned char *sha1)
+{
+       struct commit_graft *graft =
+               xmalloc(sizeof(struct commit_graft));
+       struct commit *commit = lookup_commit(sha1);
+
+       hashcpy(graft->sha1, sha1);
+       graft->nr_parent = -1;
+       if (commit && commit->object.parsed)
+               commit->parents = NULL;
+       return register_commit_graft(graft, 0);
+}
+
+int is_repository_shallow()
+{
+       FILE *fp;
+       char buf[1024];
+
+       if (is_shallow >= 0)
+               return is_shallow;
+
+       fp = fopen(git_path("shallow"), "r");
+       if (!fp) {
+               is_shallow = 0;
+               return is_shallow;
+       }
+       is_shallow = 1;
+
+       while (fgets(buf, sizeof(buf), fp)) {
+               unsigned char sha1[20];
+               if (get_sha1_hex(buf, sha1))
+                       die("bad shallow line: %s", buf);
+               register_shallow(sha1);
+       }
+       fclose(fp);
+       return is_shallow;
+}
+
+struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
+               int shallow_flag, int not_shallow_flag)
+{
+       int i = 0, cur_depth = 0;
+       struct commit_list *result = NULL;
+       struct object_array stack = {0, 0, NULL};
+       struct commit *commit = NULL;
+
+       while (commit || i < heads->nr || stack.nr) {
+               struct commit_list *p;
+               if (!commit) {
+                       if (i < heads->nr) {
+                               commit = (struct commit *)
+                                       deref_tag(heads->objects[i++].item, NULL, 0);
+                               if (commit->object.type != OBJ_COMMIT) {
+                                       commit = NULL;
+                                       continue;
+                               }
+                               if (!commit->util)
+                                       commit->util = xmalloc(sizeof(int));
+                               *(int *)commit->util = 0;
+                               cur_depth = 0;
+                       } else {
+                               commit = (struct commit *)
+                                       stack.objects[--stack.nr].item;
+                               cur_depth = *(int *)commit->util;
+                       }
+               }
+               parse_commit(commit);
+               commit->object.flags |= not_shallow_flag;
+               cur_depth++;
+               for (p = commit->parents, commit = NULL; p; p = p->next) {
+                       if (!p->item->util) {
+                               int *pointer = xmalloc(sizeof(int));
+                               p->item->util = pointer;
+                               *pointer =  cur_depth;
+                       } else {
+                               int *pointer = p->item->util;
+                               if (cur_depth >= *pointer)
+                                       continue;
+                               *pointer = cur_depth;
+                       }
+                       if (cur_depth < depth) {
+                               if (p->next)
+                                       add_object_array(&p->item->object,
+                                                       NULL, &stack);
+                               else {
+                                       commit = p->item;
+                                       cur_depth = *(int *)commit->util;
+                               }
+                       } else {
+                               commit_list_insert(p->item, &result);
+                               p->item->object.flags |= shallow_flag;
+                       }
+               }
+       }
+
+       return result;
+}
+
index f7625a6f4634da4b78c90defdc0a302c8ea4e231..77c3c575d89ad5707ad8f6b22f62b58aef458104 100755 (executable)
@@ -128,4 +128,54 @@ pull_to_client 2nd "B" $((64*3))
 
 pull_to_client 3rd "A" $((1*3)) # old fails
 
+test_expect_success "clone shallow" "git-clone --depth 2 . shallow"
+
+(cd shallow; git-count-objects -v) > count.shallow
+
+test_expect_success "clone shallow object count" \
+       "test \"in-pack: 18\" = \"$(grep in-pack count.shallow)\""
+
+count_output () {
+       sed -e '/^in-pack:/d' -e '/^packs:/d' -e '/: 0$/d' "$1"
+}
+
+test_expect_success "clone shallow object count (part 2)" '
+       test -z "$(count_output count.shallow)"
+'
+
+test_expect_success "fsck in shallow repo" \
+       "(cd shallow; git-fsck-objects --full)"
+
+#test_done; exit
+
+add B66 $B65
+add B67 $B66
+
+test_expect_success "pull in shallow repo" \
+       "(cd shallow; git pull .. B)"
+
+(cd shallow; git-count-objects -v) > count.shallow
+test_expect_success "clone shallow object count" \
+       "test \"count: 6\" = \"$(grep count count.shallow)\""
+
+add B68 $B67
+add B69 $B68
+
+test_expect_success "deepening pull in shallow repo" \
+       "(cd shallow; git pull --depth 4 .. B)"
+
+(cd shallow; git-count-objects -v) > count.shallow
+test_expect_success "clone shallow object count" \
+       "test \"count: 12\" = \"$(grep count count.shallow)\""
+
+test_expect_success "deepening fetch in shallow repo" \
+       "(cd shallow; git fetch --depth 4 .. A:A)"
+
+(cd shallow; git-count-objects -v) > count.shallow
+test_expect_success "clone shallow object count" \
+       "test \"count: 18\" = \"$(grep count count.shallow)\""
+
+test_expect_failure "pull in shallow repo with missing merge base" \
+       "(cd shallow; git pull --depth 4 .. A)"
+
 test_done
index 32b06b2e66099787d621c2557a8a9ee00aec4be6..c568ef066c9e7e0021468cfe7cb904f40ac477f1 100644 (file)
@@ -6,6 +6,9 @@
 #include "object.h"
 #include "commit.h"
 #include "exec_cmd.h"
+#include "diff.h"
+#include "revision.h"
+#include "list-objects.h"
 
 static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
 
@@ -16,6 +19,10 @@ static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=n
 #define COMMON_KNOWN   (1u << 14)
 #define REACHABLE      (1u << 15)
 
+#define SHALLOW                (1u << 16)
+#define NOT_SHALLOW    (1u << 17)
+#define CLIENT_SHALLOW (1u << 18)
+
 static unsigned long oldest_have;
 
 static int multi_ack, nr_our_refs;
@@ -54,6 +61,40 @@ static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
        return safe_write(fd, data, sz);
 }
 
+FILE *pack_pipe = NULL;
+static void show_commit(struct commit *commit)
+{
+       if (commit->object.flags & BOUNDARY)
+               fputc('-', pack_pipe);
+       if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0)
+               die("broken output pipe");
+       fputc('\n', pack_pipe);
+       fflush(pack_pipe);
+       free(commit->buffer);
+       commit->buffer = NULL;
+}
+
+static void show_object(struct object_array_entry *p)
+{
+       /* An object with name "foo\n0000000..." can be used to
+        * confuse downstream git-pack-objects very badly.
+        */
+       const char *ep = strchr(p->name, '\n');
+       if (ep) {
+               fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(p->item->sha1),
+                      (int) (ep - p->name),
+                      p->name);
+       }
+       else
+               fprintf(pack_pipe, "%s %s\n",
+                               sha1_to_hex(p->item->sha1), p->name);
+}
+
+static void show_edge(struct commit *commit)
+{
+       fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1));
+}
+
 static void create_pack_file(void)
 {
        /* Pipes between rev-list to pack-objects, pack-objects to us
@@ -75,48 +116,40 @@ static void create_pack_file(void)
 
        if (!pid_rev_list) {
                int i;
-               int args;
-               const char **argv;
-               const char **p;
-               char *buf;
+               struct rev_info revs;
 
-               if (create_full_pack) {
-                       args = 10;
-                       use_thin_pack = 0; /* no point doing it */
-               }
-               else
-                       args = have_obj.nr + want_obj.nr + 5;
-               p = xmalloc(args * sizeof(char *));
-               argv = (const char **) p;
-               buf = xmalloc(args * 45);
+               pack_pipe = fdopen(lp_pipe[1], "w");
 
-               dup2(lp_pipe[1], 1);
-               close(0);
-               close(lp_pipe[0]);
-               close(lp_pipe[1]);
-               *p++ = "rev-list";
-               *p++ = use_thin_pack ? "--objects-edge" : "--objects";
                if (create_full_pack)
-                       *p++ = "--all";
-               else {
+                       use_thin_pack = 0; /* no point doing it */
+               init_revisions(&revs, NULL);
+               revs.tag_objects = 1;
+               revs.tree_objects = 1;
+               revs.blob_objects = 1;
+               if (use_thin_pack)
+                       revs.edge_hint = 1;
+
+               if (create_full_pack) {
+                       const char *args[] = {"rev-list", "--all", NULL};
+                       setup_revisions(2, args, &revs, NULL);
+               } else {
                        for (i = 0; i < want_obj.nr; i++) {
                                struct object *o = want_obj.objects[i].item;
-                               *p++ = buf;
-                               memcpy(buf, sha1_to_hex(o->sha1), 41);
-                               buf += 41;
+                               /* why??? */
+                               o->flags &= ~UNINTERESTING;
+                               add_pending_object(&revs, o, NULL);
                        }
-               }
-               if (!create_full_pack)
                        for (i = 0; i < have_obj.nr; i++) {
                                struct object *o = have_obj.objects[i].item;
-                               *p++ = buf;
-                               *buf++ = '^';
-                               memcpy(buf, sha1_to_hex(o->sha1), 41);
-                               buf += 41;
+                               o->flags |= UNINTERESTING;
+                               add_pending_object(&revs, o, NULL);
                        }
-               *p++ = NULL;
-               execv_git_cmd(argv);
-               die("git-upload-pack: unable to exec git-rev-list");
+                       setup_revisions(0, NULL, &revs, NULL);
+               }
+               prepare_revision_walk(&revs);
+               mark_edges_uninteresting(revs.commits, &revs, show_edge);
+               traverse_commit_list(&revs, show_commit, show_object);
+               exit(0);
        }
 
        if (pipe(pu_pipe) < 0)
@@ -456,8 +489,9 @@ static int get_common_commits(void)
 
 static void receive_needs(void)
 {
+       struct object_array shallows = {0, 0, NULL};
        static char line[1000];
-       int len;
+       int len, depth = 0;
 
        for (;;) {
                struct object *o;
@@ -465,8 +499,29 @@ static void receive_needs(void)
                len = packet_read_line(0, line, sizeof(line));
                reset_timeout();
                if (!len)
-                       return;
+                       break;
 
+               if (!strncmp("shallow ", line, 8)) {
+                       unsigned char sha1[20];
+                       struct object *object;
+                       use_thin_pack = 0;
+                       if (get_sha1(line + 8, sha1))
+                               die("invalid shallow line: %s", line);
+                       object = parse_object(sha1);
+                       if (!object)
+                               die("did not find object for %s", line);
+                       object->flags |= CLIENT_SHALLOW;
+                       add_object_array(object, NULL, &shallows);
+                       continue;
+               }
+               if (!strncmp("deepen ", line, 7)) {
+                       char *end;
+                       use_thin_pack = 0;
+                       depth = strtol(line + 7, &end, 0);
+                       if (end == line + 7 || depth <= 0)
+                               die("Invalid deepen: %s", line);
+                       continue;
+               }
                if (strncmp("want ", line, 5) ||
                    get_sha1_hex(line+5, sha1_buf))
                        die("git-upload-pack: protocol error, "
@@ -498,11 +553,58 @@ static void receive_needs(void)
                        add_object_array(o, NULL, &want_obj);
                }
        }
+       if (depth == 0 && shallows.nr == 0)
+               return;
+       if (depth > 0) {
+               struct commit_list *result, *backup;
+               int i;
+               backup = result = get_shallow_commits(&want_obj, depth,
+                       SHALLOW, NOT_SHALLOW);
+               while (result) {
+                       struct object *object = &result->item->object;
+                       if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
+                               packet_write(1, "shallow %s",
+                                               sha1_to_hex(object->sha1));
+                               register_shallow(object->sha1);
+                       }
+                       result = result->next;
+               }
+               free_commit_list(backup);
+               for (i = 0; i < shallows.nr; i++) {
+                       struct object *object = shallows.objects[i].item;
+                       if (object->flags & NOT_SHALLOW) {
+                               struct commit_list *parents;
+                               packet_write(1, "unshallow %s",
+                                       sha1_to_hex(object->sha1));
+                               object->flags &= ~CLIENT_SHALLOW;
+                               /* make sure the real parents are parsed */
+                               unregister_shallow(object->sha1);
+                               object->parsed = 0;
+                               parse_commit((struct commit *)object);
+                               parents = ((struct commit *)object)->parents;
+                               while (parents) {
+                                       add_object_array(&parents->item->object,
+                                                       NULL, &want_obj);
+                                       parents = parents->next;
+                               }
+                       }
+                       /* make sure commit traversal conforms to client */
+                       register_shallow(object->sha1);
+               }
+               packet_flush(1);
+       } else
+               if (shallows.nr > 0) {
+                       int i;
+                       for (i = 0; i < shallows.nr; i++)
+                               register_shallow(shallows.objects[i].item->sha1);
+               }
+       free(shallows.objects);
 }
 
 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 {
-       static const char *capabilities = "multi_ack thin-pack side-band side-band-64k ofs-delta";
+       static const char *capabilities = "multi_ack thin-pack side-band"
+               " side-band-64k ofs-delta shallow";
        struct object *o = parse_object(sha1);
 
        if (!o)