From 23da4dfb823e55b50fe5c4528abfe988a43db3c6 Mon Sep 17 00:00:00 2001
From: rofl0r <rofl0r@users.noreply.github.com>
Date: Sun, 19 Dec 2021 18:23:57 +0000
Subject: [PATCH] propagate error exit status of called process

previously jobflow ignored when a process returned error exit
status (plus it failed to recognize abnormal process termination
of a child, like SIGSEGV and went into an endless loop in such a
case).

the new behaviour is that when a child process fails, execution
stops and jobflow returns error exit status (although not the same,
as different child processes may return different error status).
the returned error status is always 1.
---
 jobflow.c | 32 +++++++++++++++++++++++---------
 1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/jobflow.c b/jobflow.c
index 9abec59..c090f82 100644
--- a/jobflow.c
+++ b/jobflow.c
@@ -321,13 +321,14 @@ static void close_pipes(void) {
 }
 
 /* wait till a child exits, reap it, and return its job index for slot reuse */
-static size_t reap_child(void) {
+static size_t reap_child(int *retval) {
 	size_t i;
 	job_info* job;
-	int ret, retval;
+	int ret;
 
-	do ret = waitpid(-1, &retval, 0);
-	while(ret == -1 || !WIFEXITED(retval));
+	do ret = waitpid(-1, retval, 0);
+	while(ret == -1 && errno == EINTR);
+	if(ret == -1) abort();
 
 	for(i = 0; i < sblist_getsize(prog_state.job_infos); i++) {
 		job = sblist_get(prog_state.job_infos, i);
@@ -706,6 +707,11 @@ static void chomp(char *s, size_t *len) {
 	while(*len && islb(s[*len-1])) s[--(*len)] = 0;
 }
 
+static int process_failed(int retval) {
+	return WIFSIGNALED(retval) ||
+	       (WIFEXITED(retval) && WEXITSTATUS(retval));
+}
+
 #define MAX_SUBSTS 16
 static int dispatch_line(char* inbuf, size_t len, char** argv) {
 	char subst_buf[MAX_SUBSTS][4096];
@@ -750,6 +756,7 @@ static int dispatch_line(char* inbuf, size_t len, char** argv) {
 
 	char *line = inbuf;
 	size_t line_size = len;
+	int ret;
 
 	if(prog_state.subst_entries) {
 		unsigned max_subst = 0;
@@ -758,7 +765,6 @@ static int dispatch_line(char* inbuf, size_t len, char** argv) {
 			if(max_subst >= MAX_SUBSTS) break;
 			char *source = argv[*index + prog_state.cmd_startarg];
 			size_t source_len = strlen(source);
-			int ret;
 			ret = substitute_all(subst_buf[max_subst], 4096,
 					     source, source_len,
 					     "{}", 2,
@@ -799,10 +805,14 @@ static int dispatch_line(char* inbuf, size_t len, char** argv) {
 		spinup_counter++;
 	}
 
+	ret = 1;
 	if(free_slots())
 		launch_job(prog_state.threads_running, prog_state.cmd_argv);
-	else if(!prog_state.pipe_mode)
-		launch_job(reap_child(), prog_state.cmd_argv);
+	else if(!prog_state.pipe_mode) {
+		int retval;
+		launch_job(reap_child(&retval), prog_state.cmd_argv);
+		ret = !process_failed(retval);
+	}
 
 	if(prog_state.statefile && (prog_state.delayedflush == 0 || free_slots() == 0)) {
 		write_statefile(prog_state.lineno, prog_state.temp_state);
@@ -811,7 +821,7 @@ static int dispatch_line(char* inbuf, size_t len, char** argv) {
 	if(prog_state.pipe_mode)
 		pass_stdin(line, line_size);
 
-	return 1;
+	return ret;
 }
 
 int main(int argc, char** argv) {
@@ -921,7 +931,11 @@ int main(int argc, char** argv) {
 	if(prog_state.delayedflush)
 		write_statefile(prog_state.lineno - 1, prog_state.temp_state);
 
-	while(prog_state.threads_running) reap_child();
+	int retval = 0;
+	while(prog_state.threads_running) {
+		reap_child(&retval);
+		if(!exitcode) exitcode = process_failed(retval);
+	}
 
 	if(prog_state.subst_entries) sblist_free(prog_state.subst_entries);
 	if(prog_state.job_infos) sblist_free(prog_state.job_infos);
-- 
2.11.4.GIT