[PATCH 5/6] t/lib-git-daemon: add network-protocol helpers
All of our git-protocol tests rely on invoking the client and having it make a request of a server. That gives a nice real-world test of how the two behave together, but it doesn't leave any room for testing how a server might react to _other_ clients.
Let's add a few test helper functions which can be used to manually conduct a git-protocol conversation with a remote git-daemon:
1. To connect to a remote git-daemon, we need something
like "netcat". But not everybody will have netcat. And
even if they do, the behavior with respect to
half-duplex shutdowns is not portable (openbsd netcat
has "-N", with others you must rely on "-q 1", which is
racy). Here we provide a "fake_nc" that is capable of doing
a client-side netcat, with sane half-duplex semantics.
It relies on perl's IO::Socket::INET. That's been in
the base distribution since 5.6.0, so it's probably
available everywhere. But just to be on the safe side,
we'll add a prereq. 2. To help tests speak and read pktline, this patch adds
packetize() and depacketize() functions.I've put fake_nc() into lib-git-daemon.sh, since that's really the only server where we'd need to use a network socket. Whereas the pktline helpers may be of more general use, so I've added them to test-lib-functions.sh. Programs like upload-pack speak pktline, but can talk directly over stdio without a network socket.
Signed-off-by: Jeff King <peff@peff.net>
---
The sideband handling in depacketize() is not actually needed for this
series. But these are helpers I had written long ago for some
unpublished work, and they have come in handy a few times.
t/lib-git-daemon.sh | 25 ++++++++++++++++++++++++-
t/test-lib-functions.sh | 34 ++++++++++++++++++++++++++++++++++
2 files changed, 58 insertions(+), 1 deletion(-)
Show changes to 2 files +58 −1
t/lib-git-daemon.sh, t/test-lib-functions.sh
diff --git a/t/lib-git-daemon.sh b/t/lib-git-daemon.sh
index 19f3ffdbb1..de621c1243 100644
--- a/t/lib-git-daemon.sh
+++ b/t/lib-git-daemon.sh
@@ -32,7 +32,8 @@ LIB_GIT_DAEMON_PORT=${LIB_GIT_DAEMON_PORT-${this_test#t}}
GIT_DAEMON_PID=
GIT_DAEMON_DOCUMENT_ROOT_PATH="$PWD"/repo
-GIT_DAEMON_URL=git://127.0.0.1:$LIB_GIT_DAEMON_PORT
+GIT_DAEMON_HOST_PORT=127.0.0.1:$LIB_GIT_DAEMON_PORT
+GIT_DAEMON_URL=git://$GIT_DAEMON_HOST_PORT
start_git_daemon() {
if test -n "$GIT_DAEMON_PID"
@@ -98,3 +99,25 @@ stop_git_daemon() {
GIT_DAEMON_PID=
rm -f git_daemon_output
}
+
+# A stripped-down version of a netcat client, that connects to a "host:port"
+# given in $1, sends its stdin followed by EOF, then dumps the response (until
+# EOF) to stdout.
+fake_nc() {
+ if ! test_declared_prereq FAKENC
+ then
+ echo >&4 "fake_nc: need to declare FAKENC prerequisite"
+ return 127
+ fi
+ perl -Mstrict -MIO::Socket::INET -e '
+ my $s = IO::Socket::INET->new(shift)
+ or die "unable to open socket: $!";
+ print $s <STDIN>;
+ $s->shutdown(1);
+ print <$s>;
+ ' "$@"
+}
+
+test_lazy_prereq FAKENC '
+ perl -MIO::Socket::INET -e "exit 0"
+'
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index 1701fe2a06..a679b02a1c 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -1020,3 +1020,37 @@ nongit () {
"$@"
)
}
+
+# convert stdin to pktline representation; note that empty input becomes an
+# empty packet, not a flush packet (for that you can just print 0000 yourself).
+packetize() {
+ cat >packetize.tmp &&
+ len=$(wc -c <packetize.tmp) &&
+ printf '%04x%s' "$(($len + 4))" &&
+ cat packetize.tmp &&
+ rm -f packetize.tmp
+}
+
+# Parse the input as a series of pktlines, writing the result to stdout.
+# Sideband markers are removed automatically, and the output is routed to
+# stderr if appropriate.
+#
+# NUL bytes are converted to "\\0" for ease of parsing with text tools.
+depacketize () {
+ perl -e '
+ while (read(STDIN, $len, 4) == 4) {
+ if ($len eq "0000") {
+ print "FLUSH\n";
+ } else {
+ read(STDIN, $buf, hex($len) - 4);
+ $buf =~ s/\0/\\0/g;
+ if ($buf =~ s/^[\x2\x3]//) {
+ print STDERR $buf;
+ } else {
+ $buf =~ s/^\x1//;
+ print $buf;
+ }
+ }
+ }
+ '
+}
--
2.16.1.273.gfdaa03aa74
Jeff King
