From: Lasse Collin <lasse.collin@tukaani.org>
Date: Sun, 22 Feb 2015 17:38:48 +0000 (+0200)
Subject: xz: Use pipe2() if available.
X-Git-Tag: v5.2.1~2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7a11c4a8e5e15f13d5fa59233b3172e65428efdd;p=xz

xz: Use pipe2() if available.
---

diff --git a/configure.ac b/configure.ac
index 0efaaecc..c8fdb5e4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -626,8 +626,8 @@ gl_GETOPT
 # Find the best function to set timestamps.
 AC_CHECK_FUNCS([futimens futimes futimesat utimes utime], [break])
 
-# This is nice to have but not mandatory.
-AC_CHECK_FUNCS([posix_fadvise])
+# These are nice to have but not mandatory.
+AC_CHECK_FUNCS([posix_fadvise pipe2])
 
 TUKLIB_PROGNAME
 TUKLIB_INTEGER
diff --git a/src/xz/file_io.c b/src/xz/file_io.c
index 9bd515dd..20f512a2 100644
--- a/src/xz/file_io.c
+++ b/src/xz/file_io.c
@@ -82,7 +82,13 @@ io_init(void)
 	// we are root.
 	warn_fchown = geteuid() == 0;
 
-	// Create a pipe for the self-pipe trick.
+	// Create a pipe for the self-pipe trick. If pipe2() is available,
+	// we can avoid the fcntl() calls.
+#	ifdef HAVE_PIPE2
+	if (pipe2(user_abort_pipe, O_NONBLOCK))
+		message_fatal(_("Error creating a pipe: %s"),
+				strerror(errno));
+#	else
 	if (pipe(user_abort_pipe))
 		message_fatal(_("Error creating a pipe: %s"),
 				strerror(errno));
@@ -95,6 +101,7 @@ io_init(void)
 			message_fatal(_("Error creating a pipe: %s"),
 					strerror(errno));
 	}
+#	endif
 #endif
 
 #ifdef __DJGPP__