MFC: r289863,r289931,r290110,r290230,r290231,r290232

r290232:

Microoptimize.

r290231:

Addition to prev. commit.
In some edge cases fp->_p can be changed in _sseek(), recalculate.

r290230:

Don't seek to the end if write buffer is empty (in append modes).
PR:     204156

r290110:

Add _flags2 per jhb@ suggestion since no room left in _flags.
Rewrite O_APPEND flag checking using new __S2OAP flag.

r289931:

According to POSIX, a write operation shall start at the current size of
the stream (if mode had 'a' as the first character).

r289863:

Since no room left in the _flags, reuse __SALC for O_APPEND.
It helps to remove _fcntl() call from _ftello() and optimize seek position
calculation in _swrite().

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/libc/stdio/fmemopen.c b/lib/libc/stdio/fmemopen.c
index ebd3596..bcf187d 100644
--- a/lib/libc/stdio/fmemopen.c
+++ b/lib/libc/stdio/fmemopen.c
@@ -149,6 +149,9 @@ fmemopen(void * __restrict buf, size_t size, const char * __restrict mode)
 		return (NULL);
 	}
 
+	if (mode[0] == 'a')
+		f->_flags |= __SAPP;
+
 	/*
 	 * Turn off buffering, so a write past the end of the buffer
 	 * correctly returns a short object count.