From e985fc15754d55b5e82e464fa37ff197c7cdf3b7 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 26 Jan 2018 16:34:59 +0100 Subject: [PATCH] mingw: demonstrate that all file handles are inherited by child processes When spawning child processes, we really should be careful which file handles we let them inherit. This is doubly important on Windows, where we cannot rename, delete, or modify files if there is still a file handle open. Sadly, we have to guard this test inside #ifdef WIN32: we need to use the value of the HANDLE directly, and that concept does not exist on Linux/Unix. Signed-off-by: Johannes Schindelin --- t/helper/test-run-command.c | 47 +++++++++++++++++++++++++++++++++++++ t/t0061-run-command.sh | 4 ++++ 2 files changed, 51 insertions(+) diff --git a/t/helper/test-run-command.c b/t/helper/test-run-command.c index 2cc93bb69c..e1bc58b956 100644 --- a/t/helper/test-run-command.c +++ b/t/helper/test-run-command.c @@ -50,11 +50,58 @@ static int task_finished(int result, return 1; } +static int inherit_handle(const char *argv0) +{ + struct child_process cp = CHILD_PROCESS_INIT; + char path[PATH_MAX]; + int tmp; + + /* First, open an inheritable handle */ + xsnprintf(path, sizeof(path), "out-XXXXXX"); + tmp = xmkstemp(path); + + argv_array_pushl(&cp.args, + "test-tool", argv0, "inherited-handle-child", NULL); + cp.in = -1; + cp.no_stdout = cp.no_stderr = 1; + if (start_command(&cp) < 0) + die("Could not start child process"); + + /* Then close it, and try to delete it. */ + close(tmp); + if (unlink(path)) + die("Could not delete '%s'", path); + + if (close(cp.in) < 0 || finish_command(&cp) < 0) + die("Child did not finish"); + + return 0; +} + +static int inherit_handle_child(void) +{ + struct strbuf buf = STRBUF_INIT; + + if (strbuf_read(&buf, 0, 0) < 0) + die("Could not read stdin"); + printf("Received %s\n", buf.buf); + strbuf_release(&buf); + + return 0; +} + int cmd__run_command(int argc, const char **argv) { struct child_process proc = CHILD_PROCESS_INIT; int jobs; + if (argc < 2) + return 1; + if (!strcmp(argv[1], "inherited-handle")) + exit(inherit_handle(argv[0])); + if (!strcmp(argv[1], "inherited-handle-child")) + exit(inherit_handle_child()); + if (argc < 3) return 1; while (!strcmp(argv[1], "env")) { diff --git a/t/t0061-run-command.sh b/t/t0061-run-command.sh index 015fac8b5d..81ace52618 100755 --- a/t/t0061-run-command.sh +++ b/t/t0061-run-command.sh @@ -12,6 +12,10 @@ cat >hello-script <<-EOF cat hello-script EOF +test_expect_failure MINGW 'subprocess inherits only std handles' ' + test-tool run-command inherited-handle +' + test_expect_success 'start_command reports ENOENT (slash)' ' test-tool run-command start-command-ENOENT ./does-not-exist 2>err && test_i18ngrep "\./does-not-exist" err