From b60974fac8a2f4c85cbb2ca788fc4ec3e81998f9 Mon Sep 17 00:00:00 2001 From: Thomas Devoogdt Date: Tue, 17 Aug 2021 11:54:49 +0200 Subject: [PATCH] util: os_same_file_description: fix unknown linux < 3.5 syscall SYS_kcmp MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit https://man7.org/linux/man-pages/man2/kcmp.2.html The kcmp() system call first appeared in Linux 3.5. But was probably also not supported by all major platforms at that time. So fallback to the check that is done for windows. Signed-off-by: Thomas Devoogdt Acked-by: Yonggang Luo Acked-by: Michel Dänzer Upstream: https://gitlab.freedesktop.org/mesa/mesa/-/commit/3ef514982441ce496aa127611edd26b9867f4b95 Signed-off-by: Thomas Devoogdt --- src/util/os_file.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/src/util/os_file.c b/src/util/os_file.c index 5fb30f2d908..464425a9b87 100644 --- a/src/util/os_file.c +++ b/src/util/os_file.c @@ -202,29 +202,23 @@ os_read_file(const char *filename, size_t *size) /* copied from */ #define KCMP_FILE 0 +#endif + int os_same_file_description(int fd1, int fd2) { +#ifdef SYS_kcmp pid_t pid = getpid(); +#endif /* Same file descriptor trivially implies same file description */ if (fd1 == fd2) return 0; +#ifdef SYS_kcmp return syscall(SYS_kcmp, pid, pid, KCMP_FILE, fd1, fd2); -} - #else - -int -os_same_file_description(int fd1, int fd2) -{ - /* Same file descriptor trivially implies same file description */ - if (fd1 == fd2) - return 0; - /* Otherwise we can't tell */ return -1; -} - #endif +} -- 2.34.1