From 76797253acd5061c0c734b1f28f0ad1deb862a74 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@suse.de>
Date: Wed, 26 Apr 2006 15:28:10 +0200
Subject: [PATCH] [PATCH] Formalize input/output pipe checking

---
 ktee-net.c   |  8 +-------
 ktee.c       |  8 +-------
 splice-in.c  |  6 +-----
 splice-net.c |  8 +-------
 splice-out.c |  8 +-------
 splice.h     | 31 +++++++++++++++++++++++++++++++
 vmsplice.c   |  8 +-------
 7 files changed, 37 insertions(+), 40 deletions(-)

diff --git a/ktee-net.c b/ktee-net.c
index 766531e..3ae2529 100644
--- a/ktee-net.c
+++ b/ktee-net.c
@@ -10,7 +10,6 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <netdb.h>
-#include <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
 #include <limits.h>
@@ -41,18 +40,13 @@ int main(int argc, char *argv[])
 {
 	struct sockaddr_in addr;
 	char *p, *hname;
-	struct stat sb;
 	int fd;
 
 	if (argc < 2)
 		return usage(argv[0]);
 
-	if (fstat(STDIN_FILENO, &sb) < 0)
-		return error("stat");
-	if (!S_ISFIFO(sb.st_mode)) {
-		fprintf(stderr, "stdin must be a pipe\n");
+	if (check_input_pipe())
 		return usage(argv[0]);
-	}
 
 	hname = strdup(argv[1]);
 	p = strstr(hname, ":");
diff --git a/ktee.c b/ktee.c
index dda5c08..a01211b 100644
--- a/ktee.c
+++ b/ktee.c
@@ -8,7 +8,6 @@
 #include <string.h>
 #include <fcntl.h>
 #include <string.h>
-#include <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
 #include <assert.h>
@@ -38,18 +37,13 @@ static int usage(char *name)
 
 int main(int argc, char *argv[])
 {
-	struct stat sb;
 	int fd;
 
 	if (argc < 2)
 		return usage(argv[0]);
 
-	if (fstat(STDIN_FILENO, &sb) < 0)
-		return error("stat");
-	if (!S_ISFIFO(sb.st_mode)) {
-		fprintf(stderr, "stdout must be a pipe\n");
+	if (check_input_pipe())
 		return usage(argv[0]);
-	}
 
 	fd = open(argv[1], O_WRONLY | O_CREAT | O_TRUNC, 0644);
 	if (fd < 0)
diff --git a/splice-in.c b/splice-in.c
index 82c47c4..14b31f1 100644
--- a/splice-in.c
+++ b/splice-in.c
@@ -24,12 +24,8 @@ int main(int argc, char *argv[])
 	if (argc < 2)
 		return usage(argv[0]);
 
-	if (fstat(STDOUT_FILENO, &sb) < 0)
-		return error("stat");
-	if (!S_ISFIFO(sb.st_mode)) {
-		fprintf(stderr, "stdout must be a pipe\n");
+	if (check_output_pipe())
 		return usage(argv[0]);
-	}
 
 	fd = open(argv[1], O_RDONLY);
 	if (fd < 0)
diff --git a/splice-net.c b/splice-net.c
index c7df534..2c117d9 100644
--- a/splice-net.c
+++ b/splice-net.c
@@ -12,7 +12,6 @@
 #include <arpa/inet.h>
 #include <string.h>
 #include <sys/time.h>
-#include <sys/stat.h>
 #include <errno.h>
 
 #include "splice.h"
@@ -28,17 +27,12 @@ int main(int argc, char *argv[])
 	struct sockaddr_in addr;
 	unsigned short port;
 	int fd, ret;
-	struct stat sb;
 
 	if (argc < 3)
 		return usage(argv[0]);
 
-	if (fstat(STDIN_FILENO, &sb) < 0)
-		return error("stat");
-	if (!S_ISFIFO(sb.st_mode)) {
-		fprintf(stderr, "stdin must be a pipe\n");
+	if (check_input_pipe())
 		return usage(argv[0]);
-	}
 
 	port = atoi(argv[2]);
 
diff --git a/splice-out.c b/splice-out.c
index b388b86..fe62b51 100644
--- a/splice-out.c
+++ b/splice-out.c
@@ -5,7 +5,6 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <fcntl.h>
-#include <sys/stat.h>
 
 #include "splice.h"
 
@@ -37,15 +36,10 @@ static int parse_options(int argc, char *argv[])
 
 int main(int argc, char *argv[])
 {
-	struct stat sb;
 	int fd, index;
 
-	if (fstat(STDIN_FILENO, &sb) < 0)
-		return error("stat");
-	if (!S_ISFIFO(sb.st_mode)) {
-		fprintf(stderr, "stdin must be a pipe\n");
+	if (check_input_pipe())
 		return usage(argv[0]);
-	}
 
 	index = parse_options(argc, argv);
 	if (index == -1 || index + 1 > argc)
diff --git a/splice.h b/splice.h
index 5b8c254..7befe3d 100644
--- a/splice.h
+++ b/splice.h
@@ -2,6 +2,7 @@
 #define SPLICE_H
 
 #include <sys/uio.h>
+#include <sys/stat.h>
 
 #if defined(__i386__)
 #define __NR_splice	313
@@ -74,4 +75,34 @@ static inline int error(const char *n)
 	return -1;
 }
 
+static int __check_pipe(int pfd)
+{
+	struct stat sb;
+
+	if (fstat(pfd, &sb) < 0)
+		return error("stat");
+	if (!S_ISFIFO(sb.st_mode))
+		return 1;
+
+	return 0;
+}
+
+static inline int check_input_pipe(void)
+{
+	if (!__check_pipe(STDIN_FILENO))
+		return 0;
+
+	fprintf(stderr, "stdin must be a pipe\n");
+	return 1;
+}
+
+static inline int check_output_pipe(void)
+{
+	if (!__check_pipe(STDOUT_FILENO))
+		return 0;
+
+	fprintf(stderr, "stdout must be a pipe\n");
+	return 1;
+}
+
 #endif
diff --git a/vmsplice.c b/vmsplice.c
index 72befbe..5c0b1ed 100644
--- a/vmsplice.c
+++ b/vmsplice.c
@@ -9,7 +9,6 @@
 #include <string.h>
 #include <getopt.h>
 #include <sys/poll.h>
-#include <sys/stat.h>
 #include <sys/types.h>
 
 #include "splice.h"
@@ -95,17 +94,12 @@ static int parse_options(int argc, char *argv[])
 int main(int argc, char *argv[])
 {
 	unsigned char *b1, *b2;
-	struct stat sb;
 
 	if (parse_options(argc, argv) < 0)
 		return usage(argv[0]);
 
-	if (fstat(STDOUT_FILENO, &sb) < 0)
-		return error("stat");
-	if (!S_ISFIFO(sb.st_mode)) {
-		fprintf(stderr, "stdout must be a pipe\n");
+	if (check_output_pipe())
 		return usage(argv[0]);
-	}
 
 	b1 = ALIGN(malloc(SPLICE_SIZE + align_mask));
 	b2 = ALIGN(malloc(SPLICE_SIZE + align_mask));
-- 
2.25.1