From: Jeremy Kerr <jk@ozlabs.org>
Date: Tue, 14 Jan 2014 07:44:10 +0000 (+0800)
Subject: lib/process: Add add_stderr flag to process module
X-Git-Tag: v1.0.0~274
X-Git-Url: http://git.ozlabs.org/?a=commitdiff_plain;ds=inline;h=33527e065d9506e05f61c020a473544123c0601b;p=petitboot

lib/process: Add add_stderr flag to process module

For some process execution functions, we'd like to capture stderr as
well as stdout. Currently, we unconditionally redirect subprocess stderr
to the petitboot log file.

This change adds an add_stderr flag to struct process, which indicates
to the process library that we want stderr as well as stdout. If this is
specified, the subprocess' stderr is captured to stdout_buf.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
---

diff --git a/lib/process/process.c b/lib/process/process.c
index 1a16fb6..3c81b29 100644
--- a/lib/process/process.c
+++ b/lib/process/process.c
@@ -125,7 +125,10 @@ static void process_setup_stdout_child(struct process_info *procinfo)
 	else
 		dup2(log, STDOUT_FILENO);
 
-	dup2(log, STDERR_FILENO);
+	if (procinfo->process.keep_stdout && procinfo->process.add_stderr)
+		dup2(procinfo->stdout_pipe[1], STDERR_FILENO);
+	else
+		dup2(log, STDERR_FILENO);
 }
 
 static void process_finish_stdout(struct process_info *procinfo)
diff --git a/lib/process/process.h b/lib/process/process.h
index caeda92..ae7fe32 100644
--- a/lib/process/process.h
+++ b/lib/process/process.h
@@ -31,6 +31,7 @@ struct process {
 	const char		*path;
 	const char		**argv;
 	bool			keep_stdout;
+	bool			add_stderr;
 	process_exit_cb		exit_cb;
 	void			*data;
 
diff --git a/test/lib/Makefile.am b/test/lib/Makefile.am
index 3606710..ae6027f 100644
--- a/test/lib/Makefile.am
+++ b/test/lib/Makefile.am
@@ -26,6 +26,8 @@ check_PROGRAMS = list-test \
 	test-process-noargs \
 	test-process-sync \
 	test-process-sync-stdout \
+	test-process-stderr \
+	test-process-stderr-stdout \
 	test-process-async \
 	test-process-async-stdout \
 	test-process-parent-stdout \
diff --git a/test/lib/test-process-stderr-stdout.c b/test/lib/test-process-stderr-stdout.c
new file mode 100644
index 0000000..3192306
--- /dev/null
+++ b/test/lib/test-process-stderr-stdout.c
@@ -0,0 +1,57 @@
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#include <process/process.h>
+#include <waiter/waiter.h>
+#include <talloc/talloc.h>
+
+static int do_child(void)
+{
+	fprintf(stderr, "forty ");
+	fflush(stderr);
+	fprintf(stdout, "two\n");
+	fflush(stdout);
+	return 42;
+}
+
+int main(int argc, char **argv)
+{
+	struct waitset *waitset;
+	struct process *process;
+	const char *child_argv[3];
+	void *ctx;
+
+	if (argc == 2 && !strcmp(argv[1], "child"))
+		return do_child();
+
+	ctx = talloc_new(NULL);
+
+	waitset = waitset_create(ctx);
+
+	process_init(ctx, waitset, false);
+
+	child_argv[0] = argv[0];
+	child_argv[1] = "child";
+	child_argv[2] = NULL;
+
+	process = process_create(ctx);
+	process->path = child_argv[0];
+	process->argv = child_argv;
+	process->keep_stdout = true;
+	process->add_stderr = true;
+
+	process_run_sync(process);
+
+	assert(WIFEXITED(process->exit_status));
+	assert(WEXITSTATUS(process->exit_status) == 42);
+
+	assert(process->stdout_len == strlen("forty two\n"));
+	assert(!memcmp(process->stdout_buf, "forty two\n",
+				process->stdout_len));
+
+	talloc_free(ctx);
+
+	return EXIT_SUCCESS;
+}
diff --git a/test/lib/test-process-stderr.c b/test/lib/test-process-stderr.c
new file mode 100644
index 0000000..a165caa
--- /dev/null
+++ b/test/lib/test-process-stderr.c
@@ -0,0 +1,54 @@
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#include <process/process.h>
+#include <waiter/waiter.h>
+#include <talloc/talloc.h>
+
+static int do_child(void)
+{
+	fprintf(stderr, "forty two\n");
+	return 42;
+}
+
+int main(int argc, char **argv)
+{
+	struct waitset *waitset;
+	struct process *process;
+	const char *child_argv[3];
+	void *ctx;
+
+	if (argc == 2 && !strcmp(argv[1], "child"))
+		return do_child();
+
+	ctx = talloc_new(NULL);
+
+	waitset = waitset_create(ctx);
+
+	process_init(ctx, waitset, false);
+
+	child_argv[0] = argv[0];
+	child_argv[1] = "child";
+	child_argv[2] = NULL;
+
+	process = process_create(ctx);
+	process->path = child_argv[0];
+	process->argv = child_argv;
+	process->keep_stdout = true;
+	process->add_stderr = true;
+
+	process_run_sync(process);
+
+	assert(WIFEXITED(process->exit_status));
+	assert(WEXITSTATUS(process->exit_status) == 42);
+
+	assert(process->stdout_len == strlen("forty two\n"));
+	assert(!memcmp(process->stdout_buf, "forty two\n",
+				process->stdout_len));
+
+	talloc_free(ctx);
+
+	return EXIT_SUCCESS;
+}