Support gitlinks in fast-import.

Currently fast-import/export cannot be used for
repositories with submodules. This patch extends
the relevant programs to make them correctly
process gitlinks.

Links can be represented by two forms of the
Modify command:

M 160000 SHA1 some/path

which sets the link target explicitly, or

M 160000 :mark some/path

where the mark refers to a commit. The latter
form can be used by importing tools to build
all submodules simultaneously in one physical
repository, and then simply fetch them apart.

Signed-off-by: Alexander Gavrilov <angavrilov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/git-fast-import.txt b/Documentation/git-fast-import.txt
index 2d01d0d1000d1ed3a65a5448029e1b9f6bbe6a39..c2f483a8d2aed8dc017f3172e2d5fff4bed2c450 100644 (file)
--- a/Documentation/git-fast-import.txt
+++ b/Documentation/git-fast-import.txt
@@ -481,6 +481,9 @@ in octal.  Git only supports the following modes:
   what you want.
 * `100755` or `755`: A normal, but executable, file.
 * `120000`: A symlink, the content of the file will be the link target.
+* `160000`: A gitlink, SHA-1 of the object refers to a commit in
+  another repository. Git links can only be specified by SHA or through
+  a commit mark. They are used to implement submodules.
 
 In both formats `<path>` is the complete path of the file to be added
 (if not already existing) or modified (if already existing).

diff --git a/builtin-fast-export.c b/builtin-fast-export.c
index 76f3167276d55f1ffae2b0070d3adef738328bad..a443d594602b3b80964763d3105aaa2480780a87 100644 (file)
--- a/builtin-fast-export.c
+++ b/builtin-fast-export.c
@@ -136,9 +136,18 @@ static void show_filemodify(struct diff_queue_struct *q,
                if (is_null_sha1(spec->sha1))
                        printf("D %s\n", spec->path);
                else {
-                       struct object *object = lookup_object(spec->sha1);
-                       printf("M %06o :%d %s\n", spec->mode,
-                              get_object_mark(object), spec->path);
+                       /*
+                        * Links refer to objects in another repositories;
+                        * output the SHA-1 verbatim.
+                        */
+                       if (S_ISGITLINK(spec->mode))
+                               printf("M %06o %s %s\n", spec->mode,
+                                      sha1_to_hex(spec->sha1), spec->path);
+                       else {
+                               struct object *object = lookup_object(spec->sha1);
+                               printf("M %06o :%d %s\n", spec->mode,
+                                      get_object_mark(object), spec->path);
+                       }
                }
        }
 }
@@ -196,8 +205,10 @@ static void handle_commit(struct commit *commit, struct rev_info *rev)
                diff_root_tree_sha1(commit->tree->object.sha1,
                                    "", &rev->diffopt);
 
+       /* Export the referenced blobs, and remember the marks. */
        for (i = 0; i < diff_queued_diff.nr; i++)
-               handle_object(diff_queued_diff.queue[i]->two->sha1);
+               if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
+                       handle_object(diff_queued_diff.queue[i]->two->sha1);
 
        mark_next_object(&commit->object);
        if (!is_encoding_utf8(encoding))

diff --git a/fast-import.c b/fast-import.c
index c4d054ecc7f921d15916441b8323dda28aa30d2c..7089e6f9e6c5fa9142f468e54afe7d33a6d2eec7 100644 (file)
--- a/fast-import.c
+++ b/fast-import.c
@@ -1868,6 +1868,7 @@ static void file_change_m(struct branch *b)
        case S_IFREG | 0644:
        case S_IFREG | 0755:
        case S_IFLNK:
+       case S_IFGITLINK:
        case 0644:
        case 0755:
                /* ok */
@@ -1900,7 +1901,20 @@ static void file_change_m(struct branch *b)
                p = uq.buf;
        }
 
-       if (inline_data) {
+       if (S_ISGITLINK(mode)) {
+               if (inline_data)
+                       die("Git links cannot be specified 'inline': %s",
+                               command_buf.buf);
+               else if (oe) {
+                       if (oe->type != OBJ_COMMIT)
+                               die("Not a commit (actually a %s): %s",
+                                       typename(oe->type), command_buf.buf);
+               }
+               /*
+                * Accept the sha1 without checking; it expected to be in
+                * another repository.
+                */
+       } else if (inline_data) {
                static struct strbuf buf = STRBUF_INIT;
 
                if (p != uq.buf) {

diff --git a/t/t9300-fast-import.sh b/t/t9300-fast-import.sh
index e17afa8c30b367091a4bf2175dfc2b663d07aa3b..1fc06c5a23b50d54c33755a9fce4ddd9ed3b9c79 100755 (executable)
--- a/t/t9300-fast-import.sh
+++ b/t/t9300-fast-import.sh
@@ -918,4 +918,156 @@ test_expect_success \
         grep "progress " <input >expect &&
         test_cmp expect actual'
 
+###
+### series P (gitlinks)
+###
+
+cat >input <<INPUT_END
+blob
+mark :1
+data 10
+test file
+
+reset refs/heads/sub
+commit refs/heads/sub
+mark :2
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data 12
+sub_initial
+M 100644 :1 file
+
+blob
+mark :3
+data <<DATAEND
+[submodule "sub"]
+       path = sub
+       url = "`pwd`/sub"
+DATAEND
+
+commit refs/heads/subuse1
+mark :4
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data 8
+initial
+from refs/heads/master
+M 100644 :3 .gitmodules
+M 160000 :2 sub
+
+blob
+mark :5
+data 20
+test file
+more data
+
+commit refs/heads/sub
+mark :6
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data 11
+sub_second
+from :2
+M 100644 :5 file
+
+commit refs/heads/subuse1
+mark :7
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data 7
+second
+from :4
+M 160000 :6 sub
+
+INPUT_END
+
+test_expect_success \
+       'P: supermodule & submodule mix' \
+       'git-fast-import <input &&
+        git checkout subuse1 &&
+        rm -rf sub && mkdir sub && cd sub &&
+        git init &&
+        git fetch .. refs/heads/sub:refs/heads/master &&
+        git checkout master &&
+        cd .. &&
+        git submodule init &&
+        git submodule update'
+
+SUBLAST=$(git-rev-parse --verify sub)
+SUBPREV=$(git-rev-parse --verify sub^)
+
+cat >input <<INPUT_END
+blob
+mark :1
+data <<DATAEND
+[submodule "sub"]
+       path = sub
+       url = "`pwd`/sub"
+DATAEND
+
+commit refs/heads/subuse2
+mark :2
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data 8
+initial
+from refs/heads/master
+M 100644 :1 .gitmodules
+M 160000 $SUBPREV sub
+
+commit refs/heads/subuse2
+mark :3
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data 7
+second
+from :2
+M 160000 $SUBLAST sub
+
+INPUT_END
+
+test_expect_success \
+       'P: verbatim SHA gitlinks' \
+       'git branch -D sub &&
+        git gc && git prune &&
+        git-fast-import <input &&
+        test $(git-rev-parse --verify subuse2) = $(git-rev-parse --verify subuse1)'
+
+test_tick
+cat >input <<INPUT_END
+commit refs/heads/subuse3
+mark :1
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data <<COMMIT
+corrupt
+COMMIT
+
+from refs/heads/subuse2
+M 160000 inline sub
+data <<DATA
+$SUBPREV
+DATA
+
+INPUT_END
+
+test_expect_success 'P: fail on inline gitlink' '
+    ! git-fast-import <input'
+
+test_tick
+cat >input <<INPUT_END
+blob
+mark :1
+data <<DATA
+$SUBPREV
+DATA
+
+commit refs/heads/subuse3
+mark :2
+committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+data <<COMMIT
+corrupt
+COMMIT
+
+from refs/heads/subuse2
+M 160000 :1 sub
+
+INPUT_END
+
+test_expect_success 'P: fail on blob mark in gitlink' '
+    ! git-fast-import <input'
+
 test_done

diff --git a/t/t9301-fast-export.sh b/t/t9301-fast-export.sh
index 0959f2f815ae4d6bd7a8a2a1c8388561dc85dc7d..8324f6e3bd214e6c735051b52ca095970d9f61f1 100755 (executable)
--- a/t/t9301-fast-export.sh
+++ b/t/t9301-fast-export.sh
@@ -143,4 +143,46 @@ test_expect_success 'signed-tags=strip' '
 
 '
 
+test_expect_success 'setup submodule' '
+
+       git checkout -f master &&
+       mkdir sub &&
+       cd sub &&
+       git init  &&
+       echo test file > file &&
+       git add file &&
+       git commit -m sub_initial &&
+       cd .. &&
+       git submodule add "`pwd`/sub" sub &&
+       git commit -m initial &&
+       test_tick &&
+       cd sub &&
+       echo more data >> file &&
+       git add file &&
+       git commit -m sub_second &&
+       cd .. &&
+       git add sub &&
+       git commit -m second
+
+'
+
+test_expect_success 'submodule fast-export | fast-import' '
+
+       SUBENT1=$(git ls-tree master^ sub) &&
+       SUBENT2=$(git ls-tree master sub) &&
+       rm -rf new &&
+       mkdir new &&
+       git --git-dir=new/.git init &&
+       git fast-export --signed-tags=strip --all |
+       (cd new &&
+        git fast-import &&
+        test "$SUBENT1" = "$(git ls-tree refs/heads/master^ sub)" &&
+        test "$SUBENT2" = "$(git ls-tree refs/heads/master sub)" &&
+        git checkout master &&
+        git submodule init &&
+        git submodule update &&
+        cmp sub/file ../sub/file)
+
+'
+
 test_done