less/backport-makecheck-0004-Rearrange-signal-handling-a-little.patch

From edf9b5365bf3d3e104d5a6dc055bc5110e328185 Mon Sep 17 00:00:00 2001
From: Mark Nudelman <markn@greenwoodsoftware.com>
Date: Tue, 4 Oct 2022 14:54:57 -0700
Subject: [PATCH] Rearrange signal handling a little.

---
 lesstest/lesstest.c | 18 +-----------------
 lesstest/run.c      | 27 ++++++++++++++++++++-------
 2 files changed, 21 insertions(+), 24 deletions(-)

diff --git a/lesstest/lesstest.c b/lesstest/lesstest.c
index 51f0b93..b4ce319 100644
--- a/lesstest/lesstest.c
+++ b/lesstest/lesstest.c
@@ -7,8 +7,6 @@ int verbose = 0;
 int less_quit = 0;
 int details = 0;
 char* lt_screen = "./lt_screen";
-int run_catching = 0;
-jmp_buf run_catch;
 
 static char* testfile = NULL;
 
@@ -18,11 +16,6 @@ static int usage(void) {
 	return 0;
 }
 
-static void intr_handler(int signum) {
-	less_quit = 1;
-	if (run_catching) longjmp(run_catch, 1);
-}
-
 static int setup(int argc, char* const* argv) {
 	char* logfile = NULL;
 	int ch;
@@ -55,10 +48,6 @@ static int setup(int argc, char* const* argv) {
 }
 
 int main(int argc, char* const* argv, char* const* envp) {
-	signal(SIGCHLD, child_handler);
-	signal(SIGINT,  intr_handler);
-	signal(SIGQUIT, intr_handler);
-	signal(SIGKILL, intr_handler);
 	if (!setup(argc, argv))
 		return RUN_ERR;
 	setup_term();
@@ -68,12 +57,7 @@ int main(int argc, char* const* argv, char* const* envp) {
 			usage();
 			return RUN_ERR;
 		}
-		//if (setjmp(run_catch)) {
-		//	fprintf(stderr, "\nINTR test interrupted\n");
-		//	ok = 0;
-		//} else {
-			ok = run_testfile(testfile, argv[optind]);
-		//}
+		ok = run_testfile(testfile, argv[optind]);
 	} else { // gen; create new test
 		if (optind+2 > argc) {
 			usage();
diff --git a/lesstest/run.c b/lesstest/run.c
index c07048e..252a25d 100644
--- a/lesstest/run.c
+++ b/lesstest/run.c
@@ -2,6 +2,7 @@
 #include <errno.h>
 #include <setjmp.h>
 #include <errno.h>
+#include <signal.h>
 #include <sys/wait.h>
 #include "lesstest.h"
 
@@ -9,17 +10,29 @@ extern int verbose;
 extern int less_quit;
 extern int details;
 extern TermInfo terminfo;
-extern int run_catching;
-extern jmp_buf run_catch;
 
 static pid_t less_pid;
+static jmp_buf run_catch;
 
 void child_handler(int signum) {
 	int status;
 	pid_t child = wait(&status);
 	if (verbose) fprintf(stderr, "child %d died, status 0x%x\n", child, status);
-	if (child == less_pid)
+	if (child == less_pid) {
+		if (verbose) fprintf(stderr, "less died\n");
 		less_quit = 1;
+	}
+}
+
+static void intr_handler(int signum) {
+	less_quit = 1;
+	longjmp(run_catch, 1);
+}
+
+static void set_intr_handler(void (*handler)(int)) {
+	signal(SIGINT,  handler);
+	signal(SIGQUIT, handler);
+	signal(SIGKILL, handler);
 }
 
 static void send_char(LessPipeline* pipeline, wchar ch) {
@@ -33,8 +46,6 @@ static void send_char(LessPipeline* pipeline, wchar ch) {
 static int read_screen(LessPipeline* pipeline, byte* buf, int buflen) {
 	if (verbose) fprintf(stderr, "gen: read screen\n");
 	send_char(pipeline, LESS_DUMP_CHAR);
-	if (less_quit) //@@@ FIXME need?
-		return 0;
 	int rn = 0;
 	for (; rn <= buflen; ++rn) {
 		if (read(pipeline->screen_out, &buf[rn], 1) != 1)
@@ -69,6 +80,7 @@ static int curr_screen_match(LessPipeline* pipeline, const byte* img, int imglen
 }
 
 int run_interactive(char* const* argv, int argc, char* const* prog_envp) {
+	signal(SIGCHLD, child_handler);
 	char* const* envp = less_envp(prog_envp, LT_ENV_PREFIX);
 	LessPipeline* pipeline = create_less_pipeline(argv, argc, envp);
 	if (pipeline == NULL)
@@ -99,6 +111,7 @@ int run_interactive(char* const* argv, int argc, char* const* prog_envp) {
 }
 
 int run_test(TestSetup* setup, FILE* testfd) {
+	signal(SIGCHLD, child_handler);
 	const char* setup_name = setup->argv[setup->argc-1];
 	fprintf(stderr, "RUN  %s\n", setup_name);
 	LessPipeline* pipeline = create_less_pipeline(setup->argv, setup->argc, 
@@ -113,7 +126,7 @@ int run_test(TestSetup* setup, FILE* testfd) {
 		fprintf(stderr, "\nINTR test interrupted\n");
 		ok = 0;
 	} else {
-		run_catching = 1;
+		set_intr_handler(intr_handler);
 		while (!less_quit) {
 			char line[10000];
 			int line_len = read_zline(testfd, line, sizeof(line));
@@ -145,8 +158,8 @@ int run_test(TestSetup* setup, FILE* testfd) {
 				return 0;
 			}
 		}
+		set_intr_handler(SIG_DFL);
 	}
-	run_catching = 0;
 	destroy_less_pipeline(pipeline);
 	fprintf(stderr, "%s %s (%d commands)\n", ok ? "OK  " : "FAIL", setup_name, cmds);
 	return ok;
-- 
2.27.0