From 06fe8e801efc0e6a098d93cf104157fb4ef705e8 Mon Sep 17 00:00:00 2001
From: "Arnold D. Robbins" <arnold@skeeve.com>
Date: Sun, 17 Jun 2018 21:52:28 +0300
Subject: [PATCH] Fix a corner case with EPIPE to stdout/stderr.

---
 awk.h       | 2 +-
 debug.c     | 4 ++--
 interpret.h | 6 +++++-
 io.c        | 9 ++++++++-
 4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/awk.h b/awk.h
index 36e71f2..cdf683d 100644
--- a/awk.h
+++ b/awk.h
@@ -1581,7 +1581,7 @@ extern struct redirect *redirect_string(const char *redir_exp_str,
 		int *errflg, int extfd, bool failure_fatal);
 extern NODE *do_close(int nargs);
 extern int flush_io(void);
-extern int close_io(bool *stdio_problem);
+extern int close_io(bool *stdio_problem, bool *got_EPIPE);
 typedef enum { CLOSE_ALL, CLOSE_TO, CLOSE_FROM } two_way_close_type;
 extern int close_rp(struct redirect *rp, two_way_close_type how);
 extern int devopen_simple(const char *name, const char *mode, bool try_real_open);
diff --git a/debug.c b/debug.c
index 3e76ae6..a587d8f 100644
--- a/debug.c
+++ b/debug.c
@@ -5398,11 +5398,11 @@ save_options(const char *file)
 static void
 close_all()
 {
-	bool stdio_problem;
+	bool stdio_problem, got_EPIPE;
 	struct command_source *cs;
 
 	(void) nextfile(& curfile, true);	/* close input data file */
-	(void) close_io(& stdio_problem);
+	(void) close_io(& stdio_problem, & got_EPIPE);
 	if (cur_srcfile->fd != INVALID_HANDLE) {
 		close(cur_srcfile->fd);
 		cur_srcfile->fd = INVALID_HANDLE;
diff --git a/interpret.h b/interpret.h
index 20fcb7a..8408a53 100644
--- a/interpret.h
+++ b/interpret.h
@@ -110,6 +110,7 @@ top:
 		case Op_atexit:
 		{
 			bool stdio_problem = false;
+			bool got_EPIPE = false;
 
 			/* avoid false source indications */
 			source = NULL;
@@ -125,7 +126,7 @@ top:
 			 * and pipes, in that it doesn't affect their exit status.
 			 * So we no longer do either.
 			 */
-			(void) close_io(& stdio_problem);
+			(void) close_io(& stdio_problem, & got_EPIPE);
 			/*
 			 * However, we do want to exit non-zero if there was a problem
 			 * with stdout/stderr, so we reinstate a slightly different
@@ -135,6 +136,9 @@ top:
 				exit_val = 1;
 
 			close_extensions();
+
+			if (got_EPIPE)
+				die_via_sigpipe();
 		}
 			break;
 
diff --git a/io.c b/io.c
index 1a1d8cc..faccb4b 100644
--- a/io.c
+++ b/io.c
@@ -1474,12 +1474,13 @@ flush_io()
 /* close_io --- close all open files, called when exiting */
 
 int
-close_io(bool *stdio_problem)
+close_io(bool *stdio_problem, bool *got_EPIPE)
 {
 	struct redirect *rp;
 	struct redirect *next;
 	int status = 0;
 
+	*stdio_problem = *got_EPIPE = false;
 	errno = 0;
 	for (rp = red_head; rp != NULL; rp = next) {
 		next = rp->next;
@@ -1505,6 +1506,9 @@ close_io(bool *stdio_problem)
 #endif
 		if (errno != EPIPE)
 			warning(_("error writing standard output (%s)"), strerror(errno));
+		else
+			*got_EPIPE = true;
+
 		status++;
 		*stdio_problem = true;
 	}
@@ -1515,6 +1519,9 @@ close_io(bool *stdio_problem)
 #endif
 		if (errno != EPIPE)
 			warning(_("error writing standard error (%s)"), strerror(errno));
+		else
+			*got_EPIPE = true;
+
 		status++;
 		*stdio_problem = true;
 	}
-- 
2.14.4