upload-pack: add deepen-since to cut shallow repos based on time

This should allow the user to say "create a shallow clone containing the
work from last year" (once the client side is fixed up, of course).

In theory deepen-since and deepen (aka --depth) can be used together to
draw the shallow boundary (whether it's intersection or union is up to
discussion, but if rev-list is used, it's likely intersection). However,
because deepen goes with a custom commit walker, we can't mix the two
yet.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index c6977bbc5af9c9bcdd21dc26ddb93588686a38d8..9251df126576f9172246e8a5d6dc919216bc3b93 100644 (file)
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -219,7 +219,8 @@ out of what the server said it could do with the first 'want' line.
 
   shallow-line      =  PKT-LINE("shallow" SP obj-id)
 
-  depth-request     =  PKT-LINE("deepen" SP depth)
+  depth-request     =  PKT-LINE("deepen" SP depth) /
+                      PKT-LINE("deepen-since" SP timestamp)
 
   first-want        =  PKT-LINE("want" SP obj-id SP capability-list)
   additional-want   =  PKT-LINE("want" SP obj-id)

diff --git a/Documentation/technical/protocol-capabilities.txt b/Documentation/technical/protocol-capabilities.txt
index eaab6b4ac723c9f5d7dde9d70fe7e01d234e7734..f08cc4e58b2b90c7f1deec86a79592519fe23508 100644 (file)
--- a/Documentation/technical/protocol-capabilities.txt
+++ b/Documentation/technical/protocol-capabilities.txt
@@ -179,6 +179,15 @@ This capability adds "deepen", "shallow" and "unshallow" commands to
 the  fetch-pack/upload-pack protocol so clients can request shallow
 clones.
 
+deepen-since
+------------
+
+This capability adds "deepen-since" command to fetch-pack/upload-pack
+protocol so the client can request shallow clones that are cut at a
+specific time, instead of depth. Internally it's equivalent of doing
+"rev-list --max-age=<timestamp>" on the server side. "deepen-since"
+cannot be used with "deepen".
+
 no-progress
 -----------
 

diff --git a/upload-pack.c b/upload-pack.c
index 93c05229cb2c451365b6c18be26af600d704b1f8..5269461cf1fac4ba5fb8fbc8e73f90e3a83dc269 100644 (file)
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -14,6 +14,7 @@
 #include "sigchain.h"
 #include "version.h"
 #include "string-list.h"
+#include "argv-array.h"
 
 static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>";
 
@@ -629,11 +630,25 @@ static void deepen(int depth, const struct object_array *shallows)
        packet_flush(1);
 }
 
+static void deepen_by_rev_list(int ac, const char **av,
+                              struct object_array *shallows)
+{
+       struct commit_list *result;
+
+       result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
+       send_shallow(result);
+       free_commit_list(result);
+       send_unshallow(shallows);
+       packet_flush(1);
+}
+
 static void receive_needs(void)
 {
        struct object_array shallows = OBJECT_ARRAY_INIT;
        int depth = 0;
        int has_non_tip = 0;
+       unsigned long deepen_since = 0;
+       int deepen_rev_list = 0;
 
        shallow_nr = 0;
        for (;;) {
@@ -670,6 +685,16 @@ static void receive_needs(void)
                                die("Invalid deepen: %s", line);
                        continue;
                }
+               if (skip_prefix(line, "deepen-since ", &arg)) {
+                       char *end = NULL;
+                       deepen_since = strtoul(arg, &end, 0);
+                       if (!end || *end || !deepen_since ||
+                           /* revisions.c's max_age -1 is special */
+                           deepen_since == -1)
+                               die("Invalid deepen-since: %s", line);
+                       deepen_rev_list = 1;
+                       continue;
+               }
                if (!skip_prefix(line, "want ", &arg) ||
                    get_sha1_hex(arg, sha1_buf))
                        die("git upload-pack: protocol error, "
@@ -721,10 +746,26 @@ static void receive_needs(void)
        if (!use_sideband && daemon_mode)
                no_progress = 1;
 
-       if (depth == 0 && shallows.nr == 0)
+       if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
                return;
+       if (depth > 0 && deepen_rev_list)
+               die("git upload-pack: deepen and deepen-since cannot be used together");
        if (depth > 0)
                deepen(depth, &shallows);
+       else if (deepen_rev_list) {
+               struct argv_array av = ARGV_ARRAY_INIT;
+               int i;
+
+               argv_array_push(&av, "rev-list");
+               if (deepen_since)
+                       argv_array_pushf(&av, "--max-age=%lu", deepen_since);
+               for (i = 0; i < want_obj.nr; i++) {
+                       struct object *o = want_obj.objects[i].item;
+                       argv_array_push(&av, oid_to_hex(&o->oid));
+               }
+               deepen_by_rev_list(av.argc, av.argv, &shallows);
+               argv_array_clear(&av);
+       }
        else
                if (shallows.nr > 0) {
                        int i;
@@ -773,7 +814,7 @@ static int send_ref(const char *refname, const struct object_id *oid,
                    int flag, void *cb_data)
 {
        static const char *capabilities = "multi_ack thin-pack side-band"
-               " side-band-64k ofs-delta shallow no-progress"
+               " side-band-64k ofs-delta shallow deepen-since no-progress"
                " include-tag multi_ack_detailed";
        const char *refname_nons = strip_namespace(refname);
        struct object_id peeled;