ctdb-common: Update run_proc api to re-assign stdin

This allows to pass data to a child process via stdin.

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
Reviewed-by: Martin Schwenke <martin@meltin.net>

5 files changed, 52 insertions, 20 deletions

diff --git a/ctdb/common/run_proc.c b/ctdb/common/run_proc.c
index f9fee80e907..53862026bd5 100644
--- a/ctdb/common/run_proc.c
+++ b/ctdb/common/run_proc.c
@@ -67,7 +67,7 @@ static void proc_read_handler(struct tevent_context *ev,
 			      void *private_data);
 
 static int proc_start(struct proc_context *proc, struct tevent_context *ev,
-		      const char *path, const char **argv)
+		      const char *path, const char **argv, int stdin_fd)
 {
 	int fd[2];
 	int ret;
@@ -99,6 +99,13 @@ static int proc_start(struct proc_context *proc, struct tevent_context *ev,
 
 		close(fd[1]);
 
+		if (stdin_fd != -1) {
+			ret = dup2(stdin_fd, STDIN_FILENO);
+			if (ret == -1) {
+				exit(64 + errno);
+			}
+		}
+
 		ret = setpgid(0, 0);
 		if (ret != 0) {
 			exit(64 + errno);
@@ -382,7 +389,7 @@ struct tevent_req *run_proc_send(TALLOC_CTX *mem_ctx,
 				 struct tevent_context *ev,
 				 struct run_proc_context *run_ctx,
 				 const char *path, const char **argv,
-				 struct timeval timeout)
+				 int stdin_fd, struct timeval timeout)
 {
 	struct tevent_req *req;
 	struct run_proc_state *state;
@@ -415,7 +422,7 @@ struct tevent_req *run_proc_send(TALLOC_CTX *mem_ctx,
 		return tevent_req_post(req, ev);
 	}
 
-	ret = proc_start(state->proc, ev, path, argv);
+	ret = proc_start(state->proc, ev, path, argv, stdin_fd);
 	if (ret != 0) {
 		tevent_req_error(req, ret);
 		return tevent_req_post(req, ev);
diff --git a/ctdb/common/run_proc.h b/ctdb/common/run_proc.h
index 4287347cc64..7de0c84f857 100644
--- a/ctdb/common/run_proc.h
+++ b/ctdb/common/run_proc.h
@@ -68,6 +68,7 @@ int run_proc_init(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
  * @param[in] run_ctx Run_proc context
  * @param[in] prog The path to the executable
  * @param[in] argv Arguments to the executable
+ * @param[in] stdin_fd Assign stdin_fd as stdin for the process, -1 if not
  * @param[in] timeout How long to wait for execution
  * @return new tevent request, or NULL on failure
  *
@@ -77,7 +78,7 @@ struct tevent_req *run_proc_send(TALLOC_CTX *mem_ctx,
 				 struct tevent_context *ev,
 				 struct run_proc_context *run_ctx,
 				 const char *prog, const char **argv,
-				 struct timeval timeout);
+				 int stdin_fd, struct timeval timeout);
 
 /**
  * @brief Async computation end to run an executable
diff --git a/ctdb/server/ctdb_eventd.c b/ctdb/server/ctdb_eventd.c
index 232711ce4e2..3542b4fb6f0 100644
--- a/ctdb/server/ctdb_eventd.c
+++ b/ctdb/server/ctdb_eventd.c
@@ -343,7 +343,7 @@ static struct tevent_req *run_debug_send(TALLOC_CTX *mem_ctx,
 		debug_script, argv[1], argv[2]);
 
 	subreq = run_proc_send(state, ev, ectx->run_ctx, debug_script, argv,
-			       tevent_timeval_zero());
+			       -1, tevent_timeval_zero());
 	if (tevent_req_nomem(subreq, req)) {
 		return tevent_req_post(req, ev);
 	}
@@ -709,7 +709,7 @@ static struct tevent_req *run_event_run_script(struct tevent_req *req)
 		path, state->argv[0], state->argv[1]);
 
 	subreq = run_proc_send(state, state->ev, state->ectx->run_ctx,
-			       path, state->argv, state->timeout);
+			       path, state->argv, -1, state->timeout);
 
 	talloc_free(path);
 
diff --git a/ctdb/tests/cunit/run_proc_001.sh b/ctdb/tests/cunit/run_proc_001.sh
index e1937a82f28..b817637e574 100755
--- a/ctdb/tests/cunit/run_proc_001.sh
+++ b/ctdb/tests/cunit/run_proc_001.sh
@@ -6,7 +6,7 @@
 ok <<EOF
 Process exited with error 2
 EOF
-unit_test run_proc_test 0 /a/b/c
+unit_test run_proc_test 0 -1 /a/b/c
 
 # Non-executable path
 prog=$(mktemp --tmpdir="$TEST_VAR_DIR")
@@ -17,7 +17,7 @@ EOF
 ok <<EOF
 Process exited with error 13
 EOF
-unit_test run_proc_test 0 "$prog"
+unit_test run_proc_test 0 -1 "$prog"
 
 # Executable path
 chmod +x "$prog"
@@ -25,7 +25,7 @@ chmod +x "$prog"
 ok <<EOF
 Process exited with error 8
 EOF
-unit_test run_proc_test 0 "$prog"
+unit_test run_proc_test 0 -1 "$prog"
 
 # Capture output
 cat > "$prog" <<EOF
@@ -38,7 +38,7 @@ Process exited with status 0
 Output = (hello
 )
 EOF
-unit_test run_proc_test 0 "$prog"
+unit_test run_proc_test 0 -1 "$prog"
 
 # Specify timeout
 ok <<EOF
@@ -46,7 +46,7 @@ Process exited with status 0
 Output = (hello
 )
 EOF
-unit_test run_proc_test 5 "$prog"
+unit_test run_proc_test 5 -1 "$prog"
 
 # Redirected output
 output=$(mktemp --tmpdir="$TEST_VAR_DIR")
@@ -59,7 +59,7 @@ EOF
 ok <<EOF
 Process exited with status 0
 EOF
-unit_test run_proc_test 0 "$prog"
+unit_test run_proc_test 0 -1 "$prog"
 
 ok <<EOF
 hello
@@ -75,7 +75,7 @@ EOF
 ok <<EOF
 Process exited with status 1
 EOF
-unit_test run_proc_test 0 "$prog"
+unit_test run_proc_test 0 -1 "$prog"
 
 # Exit with signal
 cat > "$prog" <<EOF
@@ -86,7 +86,7 @@ EOF
 ok <<EOF
 Process exited with signal 15
 EOF
-unit_test run_proc_test 0 "$prog"
+unit_test run_proc_test 0 -1 "$prog"
 
 # Exit with timeout
 cat > "$prog" <<EOF
@@ -107,7 +107,7 @@ Child = PID
 Output = (Sleeping for 5 seconds
 )
 EOF
-unit_test run_proc_test 1 "$prog"
+unit_test run_proc_test 1 -1 "$prog"
 
 # No zombie processes
 pidfile=$(mktemp --tmpdir="$TEST_VAR_DIR")
@@ -122,7 +122,7 @@ ok <<EOF
 Process exited with error 62
 Child = PID
 EOF
-unit_test run_proc_test 1 "$prog"
+unit_test run_proc_test 1 -1 "$prog"
 
 result_filter ()
 {
@@ -136,5 +136,23 @@ HEADER
 EOF
 unit_test ps -p "$pid"
 
+# Redirect stdin
+cat > "$prog" <<EOF
+#!/bin/sh
+cat -
+EOF
+
+cat > "$output" <<EOF
+this is sample input
+EOF
+
+ok <<EOF
+Process exited with status 0
+Output = (this is sample input
+)
+EOF
+(unit_test run_proc_test 0 4 "$prog") 4<"$output"
+
 rm -f "$pidfile"
+rm -f "$output"
 rm -f "$prog"
diff --git a/ctdb/tests/src/run_proc_test.c b/ctdb/tests/src/run_proc_test.c
index 6db783d378f..7cfb8703e99 100644
--- a/ctdb/tests/src/run_proc_test.c
+++ b/ctdb/tests/src/run_proc_test.c
@@ -35,11 +35,12 @@ int main(int argc, const char **argv)
 	char *output;
 	struct run_proc_result result;
 	pid_t pid;
-	int timeout, ret;
+	int timeout, ret, fd;
 	bool status;
 
-	if (argc < 3) {
-		fprintf(stderr, "Usage: %s <timeout> <program> <args>\n",
+	if (argc < 4) {
+		fprintf(stderr,
+			"Usage: %s <timeout> <stdin-fd> <program> <args>\n",
 			argv[0]);
 		exit(1);
 	}
@@ -63,13 +64,18 @@ int main(int argc, const char **argv)
 		tv = tevent_timeval_current_ofs(timeout, 0);
 	}
 
+	fd = atoi(argv[2]);
+	if (fd < 0) {
+		fd = -1;
+	}
+
 	ret = run_proc_init(mem_ctx, ev, &run_ctx);
 	if (ret != 0) {
 		fprintf(stderr, "run_proc_init() failed, ret=%d\n", ret);
 		exit(1);
 	}
 
-	req = run_proc_send(mem_ctx, ev, run_ctx, argv[2], &argv[2], tv);
+	req = run_proc_send(mem_ctx, ev, run_ctx, argv[3], &argv[3], fd, tv);
 	if (req == NULL) {
 		fprintf(stderr, "run_proc_send() failed\n");
 		exit(1);