From: Jonathan Nieder <jrnieder@xxxxxxxxx>
As the description of the "progress" option in git-fast-import.1
hints, there is no convenient way to immediately access the objects
written to a new repository through fast-import. Until a checkpoint
has been started and finishes writing the pack index, any new blobs,
trees, and commits will not be accessible using standard git tools.
So introduce another way: a "cat" command introduced in the command
stream requests for fast-import to print an object to the same
report-fd stream used to report commits being written.
The output uses the same format as "git cat-file --batch".
Like cat-file --batch, this does not provide an option to dereference
objects to a type of the requestor's choosing. Tags are presented
as tags, commits as commits, and trees as trees.
Objects can be specified by path within a tree as well, using a
cat TREE "PATH"
syntax. With this syntax, also, the tree can only be specified by
:n marker or 40-digit tree id.
Cc: Shawn O. Pearce <spearce@xxxxxxxxxxx>
Cc: David Barr <david.barr@xxxxxxxxxxxx>
Cc: Ramkumar Ramachandra <artagnon@xxxxxxxxx>
Helped-by: Sverre Rabbelier <srabbelier@xxxxxxxxx>
Signed-off-by: Jonathan Nieder <jrnieder@xxxxxxxxx>
---
Documentation/git-fast-import.txt | 34 +++++++++++-
fast-import.c | 108 +++++++++++++++++++++++++++++++++++++
t/t9300-fast-import.sh | 102 ++++++++++++++++++++++++++++++++++
3 files changed, 243 insertions(+), 1 deletions(-)
diff --git a/Documentation/git-fast-import.txt b/Documentation/git-fast-import.txt
index e217635..2cf48f5 100644
--- a/Documentation/git-fast-import.txt
+++ b/Documentation/git-fast-import.txt
@@ -102,7 +102,8 @@ OPTIONS
+
The described objects are not necessarily accessible
using standard git plumbing tools until a little while
-after the next checkpoint.
+after the next checkpoint. To request access to the
+objects before then, use `cat` lines in the command stream.
--export-pack-edges=<file>::
After creating a packfile, print a line of data to
@@ -332,6 +333,10 @@ and control the current import process. More detailed discussion
standard output. This command is optional and is not needed
to perform an import.
+`cat`::
+ Causes fast-import to print an object in 'cat-file --batch'
+ format to the file descriptor set with "feature report-fd".
+
`feature`::
Require that fast-import supports the specified feature, or
abort if it does not.
@@ -888,6 +893,33 @@ Placing a `progress` command immediately after a `checkpoint` will
inform the reader when the `checkpoint` has been completed and it
can safely access the refs that fast-import updated.
+`cat`
+~~~~~
+Causes fast-import to print an object to a file descriptor
+previously arranged with the `--report-fd` option. The command
+otherwise has no impact on the current import; its main purpose is to
+retrieve objects that may be in fast-import's memory but not
+accessible from the target repository a little quicker than by the
+method suggested by the description of the `progress` option.
+
+....
+ 'cat' SP <dataref> LF
+....
+
+The `<dataref>` can be either a mark reference (`:<idnum>`)
+set previously, or a full 40-byte SHA-1 of any Git object,
+preexisting or ready to be written.
+
+If `<dataref>` refers to a tree object, it may be followed by
+a path within that tree to retrieve a subtree or blob.
+
+....
+ 'cat' SP <treeref> SP <path> LF
+....
+
+A `<path>` string should be surrounded with quotation marks and
+use C-style escaping.
+
`feature`
~~~~~~~~~
Require that fast-import supports the specified feature, or abort if
diff --git a/fast-import.c b/fast-import.c
index ef0cee7..099f63e 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -55,6 +55,9 @@ Format of STDIN stream:
('from' sp committish lf)?
lf?;
+ cat_request ::= 'cat' sp (hexsha1 | idnum) lf
+ | 'cat' sp hexsha1 sp path_str lf;
+
checkpoint ::= 'checkpoint' lf
lf?;
@@ -2688,6 +2691,109 @@ static void parse_reset_branch(void)
unread_command_buf = 1;
}
+static void quoted_path_sha1(unsigned char sha1[20], struct tree_entry *root,
+ const char *path, const char *line)
+{
+ struct strbuf uq = STRBUF_INIT;
+ struct tree_entry leaf = {0};
+ const char *x;
+
+ if (unquote_c_style(&uq, path, &x))
+ die("Invalid path: %s", line);
+ if (*x)
+ die("Garbage after path: %s", line);
+ tree_content_get(root, uq.buf, &leaf);
+ if (!leaf.versions[1].mode)
+ die("Path %s not in branch", uq.buf);
+ hashcpy(sha1, leaf.versions[1].sha1);
+}
+
+static void sendreport(const char *buf, unsigned long size)
+{
+ if (write_in_full(report_fd, buf, size) != size)
+ die_errno("Write to frontend failed");
+}
+
+static void cat_object(struct object_entry *oe, unsigned char sha1[20])
+{
+ struct strbuf line = STRBUF_INIT;
+ unsigned long size;
+ enum object_type type = 0;
+ char *buf;
+
+ if (report_fd < 0)
+ die("Internal error: bad report_fd %d", report_fd);
+ if (oe && oe->pack_id != MAX_PACK_ID) {
+ type = oe->type;
+ buf = gfi_unpack_entry(oe, &size);
+ } else {
+ buf = read_sha1_file(sha1, &type, &size);
+ }
+ if (!buf)
+ die("Can't read object %s", sha1_to_hex(sha1));
+
+ /*
+ * Output based on batch_one_object() from cat-file.c.
+ */
+ if (type <= 0) {
+ strbuf_reset(&line);
+ strbuf_addf(&line, "%s missing\n", sha1_to_hex(sha1));
+ if (write_in_full(report_fd, line.buf, line.len) != line.len)
+ die_errno("Write to frontend failed 1");
+ }
+ strbuf_reset(&line);
+ strbuf_addf(&line, "%s %s %lu\n", sha1_to_hex(sha1),
+ typename(type), size);
+ sendreport(line.buf, line.len);
+ sendreport(buf, size);
+ sendreport("\n", 1);
+ free(buf);
+}
+
+
+static void parse_cat_request(void)
+{
+ const char *p;
+ struct object_entry *oe = oe;
+ unsigned char sha1[20];
+ struct tree_entry root = {0};
+
+ /* cat SP <object> */
+ p = command_buf.buf + strlen("cat ");
+ if (report_fd < 0)
+ die("The cat command requires the report-fd feature.");
+ if (*p == ':') {
+ char *x;
+ oe = find_mark(strtoumax(p + 1, &x, 10));
+ if (x == p + 1)
+ die("Invalid mark: %s", command_buf.buf);
+ if (!oe)
+ die("Unknown mark: %s", command_buf.buf);
+ p = x;
+ hashcpy(sha1, oe->idx.sha1);
+ } else {
+ if (get_sha1_hex(p, sha1))
+ die("Invalid SHA1: %s", command_buf.buf);
+ p += 40;
+ if (!*p)
+ oe = find_object(sha1);
+ }
+
+ /* [ SP "<path>" ] */
+ if (*p) {
+ if (*p++ != ' ')
+ die("Missing space after SHA1: %s", command_buf.buf);
+
+ /* cat <tree> "<path>" form. */
+ hashcpy(root.versions[1].sha1, sha1);
+ load_tree(&root);
+ quoted_path_sha1(sha1, &root, p, command_buf.buf);
+ oe = find_object(sha1);
+ }
+
+ cat_object(oe, sha1);
+}
+
static void parse_checkpoint(void)
{
if (object_count) {
@@ -2971,6 +3077,8 @@ int main(int argc, const char **argv)
parse_new_tag();
else if (!prefixcmp(command_buf.buf, "reset "))
parse_reset_branch();
+ else if (!prefixcmp(command_buf.buf, "cat "))
+ parse_cat_request();
else if (!strcmp("checkpoint", command_buf.buf))
parse_checkpoint();
else if (!prefixcmp(command_buf.buf, "progress "))
diff --git a/t/t9300-fast-import.sh b/t/t9300-fast-import.sh
index 4371308..8155b85 100755
--- a/t/t9300-fast-import.sh
+++ b/t/t9300-fast-import.sh
@@ -1647,6 +1647,108 @@ test_expect_success PIPE 'R: fast-import --report-fd' '
test_cmp real received
'
+test_expect_success PIPE 'R: report-fd: can feed back printed tree' '
+ cat >frontend <<-\FRONTEND_END &&
+ #!/bin/sh
+ cat <<EOF &&
+ commit refs/heads/printed
+ committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+ data <<COMMIT
+ to be printed
+ COMMIT
+
+ from refs/heads/master
+ D file3
+
+ EOF
+
+ read commit_id <&3 &&
+ echo "$commit_id" >printed &&
+ echo "$commit_id commit" >expect.response &&
+ echo "cat $commit_id" &&
+ read cid2 type size <&3 &&
+ echo "$cid2 $type" >response &&
+ dd if=/dev/stdin of=commit bs=1 count=$size <&3 &&
+ read newline <&3 &&
+ read tree tree_id <commit &&
+
+ cat <<EOF &&
+ commit refs/heads/printed
+ committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+ data <<COMMIT
+ to be printed
+ COMMIT
+
+ from refs/heads/printed^0
+ M 040000 $tree_id old
+
+ EOF
+ read cid <&3
+ FRONTEND_END
+
+ mkfifo commits &&
+ test_when_finished "rm -f commits" &&
+ sh frontend 3<commits |
+ git fast-import --report-fd=3 3>commits &&
+ git rev-parse printed^ >expect.printed &&
+ git cat-file commit printed^ >expect.commit &&
+
+ test_cmp expect.printed printed &&
+ test_cmp expect.response response &&
+ test_cmp expect.commit commit
+'
+
+test_expect_success PIPE 'R: report-fd: can feed back printed blob' '
+ file6_id=$(echo "$file6_data" | git hash-object --stdin) &&
+ cat >expect <<-EOF &&
+ :100755 100644 $file6_id $file6_id C100 newdir/exec.sh file6
+ EOF
+
+ cat >frontend <<-\FRONTEND_END &&
+ #!/bin/sh
+
+ branch=$(git rev-parse --verify refs/heads/branch) &&
+ cat <<EOF &&
+ feature report-fd=3
+ cat $branch
+ EOF
+
+ read commit_id type size <&3 &&
+ dd if=/dev/stdin of=commit bs=1 count=$size <&3 &&
+ read newline <&3 &&
+ read tree tree_id <commit &&
+
+ echo "cat $tree_id \"newdir/exec.sh\"" &&
+ read blob_id type size <&3 &&
+ dd if=/dev/stdin of=blob bs=1 count=$size <&3 &&
+ read newline <&3 &&
+
+ cat <<EOF &&
+ commit refs/heads/copyblob
+ committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+ data <<COMMIT
+ copy file6 to top level
+ COMMIT
+
+ from refs/heads/branch^0
+ M 644 inline "file6"
+ data $size
+ EOF
+ cat blob &&
+ echo &&
+ echo &&
+
+ read cid <&3
+ FRONTEND_END
+
+ mkfifo commits &&
+ test_when_finished "rm -f commits" &&
+ sh frontend 3<commits |
+ git fast-import 3>commits &&
+ git diff-tree -C --find-copies-harder -r copyblob^ copyblob >actual &&
+ compare_diff_raw expect actual
+'
+
cat >input << EOF
option git quiet
blob
--
1.7.3.1
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html