cgi-io: close pipe descriptors early

In the command read side, close the superfluous write end of the pipe
early to ensure that EOF is reliably detected. Without that change, splice
calls to read from the pipe will occasionally hang until the CGI process
is eventually killed due to timeout.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>
(cherry picked from commit dde503da13)

net/cgi-io/Makefile

@@ -8,7 +8,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=cgi-io
-PKG_RELEASE:=15
+PKG_RELEASE:=16
 
 PKG_LICENSE:=GPL-2.0-or-later
 

net/cgi-io/src/main.c

@@ -778,6 +778,8 @@ main_backup(int argc, char **argv)
 		return -1;
 
 	default:
+		close(fds[1]);
+
 		now = time(NULL);
 		strftime(datestr, sizeof(datestr) - 1, "%Y-%m-%d", localtime(&now));
 
@@ -798,7 +800,6 @@ main_backup(int argc, char **argv)
 		waitpid(pid, &status, 0);
 
 		close(fds[0]);
-		close(fds[1]);
 
 		return 0;
 	}
@@ -1010,6 +1011,8 @@ main_exec(int argc, char **argv)
 		return -1;
 
 	default:
+		close(fds[1]);
+
 		printf("Status: 200 OK\r\n");
 		printf("Content-Type: %s\r\n",
 		       fields[7] ? fields[7] : "application/octet-stream");
@@ -1028,7 +1031,6 @@ main_exec(int argc, char **argv)
 		waitpid(pid, &status, 0);
 
 		close(fds[0]);
-		close(fds[1]);
 		free(args);
 
 		return 0;