From 892cafff665b44d238e3b664f61ca38dd965cba6 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Wed, 24 Oct 2012 21:16:06 -0400 Subject: greatly improve freopen behavior 1. don't open /dev/null just as a basis to copy flags; use shared __fmodeflags function to get the right file flags for the mode. 2. handle the case (probably invalid, but whatever) case where the original stream's file descriptor was closed; previously, the logic re-closed it. 3. accept the "e" mode flag for close-on-exec; update dup3 to fallback to using dup2 so we can simply call __dup3 instead of putting fallback logic in freopen itself. --- src/stdio/__fmodeflags.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) create mode 100644 src/stdio/__fmodeflags.c (limited to 'src/stdio/__fmodeflags.c') diff --git a/src/stdio/__fmodeflags.c b/src/stdio/__fmodeflags.c new file mode 100644 index 00000000..da9f23b6 --- /dev/null +++ b/src/stdio/__fmodeflags.c @@ -0,0 +1,16 @@ +#include +#include + +int __fmodeflags(const char *mode) +{ + int flags; + if (strchr(mode, '+')) flags = O_RDWR; + else if (*mode == 'r') flags = O_RDONLY; + else flags = O_WRONLY; + if (strchr(mode, 'x')) flags |= O_EXCL; + if (strchr(mode, 'e')) flags |= O_CLOEXEC; + if (*mode != 'r') flags |= O_CREAT; + if (*mode == 'w') flags |= O_TRUNC; + if (*mode == 'a') flags |= O_APPEND; + return flags; +} -- cgit v1.2.1