From be56862f198d946dc75ac7092606e78a4f2ff1d3 Mon Sep 17 00:00:00 2001 From: Sverre Rabbelier Date: Sat, 16 Jul 2011 15:03:32 +0200 Subject: [PATCH] fast-import: introduce 'done' command Add a 'done' command that causes fast-import to stop reading from the stream and exit. If the new --done command line flag was passed on the command line (or a "feature done" declaration included at the start of the stream), make the 'done' command mandatory. So "git fast-import --done"'s input format will be prefix-free, making errors easier to detect when they show up as early termination at some convenient time of the upstream of a pipe writing to fast-import. Another possible application of the 'done' command would to be allow a fast-import stream that is only a small part of a larger encapsulating stream to be easily parsed, leaving the file offset after the "done\n" so the other application can pick up from there. This patch does not teach fast-import to do that --- fast-import still uses buffered input (stdio). Signed-off-by: Jonathan Nieder Signed-off-by: Sverre Rabbelier Acked-by: Jeff King Signed-off-by: Junio C Hamano --- Documentation/git-fast-import.txt | 25 ++++++++++++++++++ fast-import.c | 8 ++++++ t/t9300-fast-import.sh | 42 +++++++++++++++++++++++++++++++ 3 files changed, 75 insertions(+) diff --git a/Documentation/git-fast-import.txt b/Documentation/git-fast-import.txt index 249249aac..0fc68a911 100644 --- a/Documentation/git-fast-import.txt +++ b/Documentation/git-fast-import.txt @@ -101,6 +101,12 @@ OPTIONS when the `cat-blob` command is encountered in the stream. The default behaviour is to write to `stdout`. +--done:: + Require a `done` command at the end of the stream. + This option might be useful for detecting errors that + cause the frontend to terminate before it has started to + write a stream. + --export-pack-edges=:: After creating a packfile, print a line of data to listing the filename of the packfile and the last @@ -330,6 +336,11 @@ and control the current import process. More detailed discussion standard output. This command is optional and is not needed to perform an import. +`done`:: + Marks the end of the stream. This command is optional + unless the `done` feature was requested using the + `--done` command line option or `feature done` command. + `cat-blob`:: Causes fast-import to print a blob in 'cat-file --batch' format to the file descriptor set with `--cat-blob-fd` or @@ -1015,6 +1026,11 @@ notes:: Versions of fast-import not supporting notes will exit with a message indicating so. +done:: + Error out if the stream ends without a 'done' command. + Without this feature, errors causing the frontend to end + abruptly at a convenient point in the stream can go + undetected. `option` ~~~~~~~~ @@ -1044,6 +1060,15 @@ not be passed as option: * cat-blob-fd * force +`done` +~~~~~~ +If the `done` feature is not in use, treated as if EOF was read. +This can be used to tell fast-import to finish early. + +If the `--done` command line option or `feature done` command is +in use, the `done` command is mandatory and marks the end of the +stream. + Crash Reports ------------- If fast-import is supplied invalid input it will terminate with a diff --git a/fast-import.c b/fast-import.c index 78d978684..8a8a91589 100644 --- a/fast-import.c +++ b/fast-import.c @@ -354,6 +354,7 @@ static unsigned int cmd_save = 100; static uintmax_t next_mark; static struct strbuf new_data = STRBUF_INIT; static int seen_data_command; +static int require_explicit_termination; /* Signal handling */ static volatile sig_atomic_t checkpoint_requested; @@ -3139,6 +3140,8 @@ static int parse_one_feature(const char *feature, int from_stream) relative_marks_paths = 1; } else if (!strcmp(feature, "no-relative-marks")) { relative_marks_paths = 0; + } else if (!strcmp(feature, "done")) { + require_explicit_termination = 1; } else if (!strcmp(feature, "force")) { force_update = 1; } else if (!strcmp(feature, "notes") || !strcmp(feature, "ls")) { @@ -3288,6 +3291,8 @@ int main(int argc, const char **argv) parse_reset_branch(); else if (!strcmp("checkpoint", command_buf.buf)) parse_checkpoint(); + else if (!strcmp("done", command_buf.buf)) + break; else if (!prefixcmp(command_buf.buf, "progress ")) parse_progress(); else if (!prefixcmp(command_buf.buf, "feature ")) @@ -3307,6 +3312,9 @@ int main(int argc, const char **argv) if (!seen_data_command) parse_argv(); + if (require_explicit_termination && feof(stdin)) + die("stream ends early"); + end_packfile(); dump_branches(); diff --git a/t/t9300-fast-import.sh b/t/t9300-fast-import.sh index 6b1ba6c85..526231bbe 100755 --- a/t/t9300-fast-import.sh +++ b/t/t9300-fast-import.sh @@ -2197,6 +2197,48 @@ test_expect_success 'R: quiet option results in no stats being output' ' test_cmp empty output ' +test_expect_success 'R: feature done means terminating "done" is mandatory' ' + echo feature done | test_must_fail git fast-import && + test_must_fail git fast-import --done expect <<-\EOF && + OBJID + :000000 100644 OBJID OBJID A hello.c + :000000 100644 OBJID OBJID A hello2.c + EOF + git fast-import <<-EOF && + commit refs/heads/done-ends + committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE + data <actual && + test_cmp expect actual +' + cat >input <