From 656df313e08a9ac4ef33c553285bb52d23c3e15f Mon Sep 17 00:00:00 2001 From: Corinna Vinschen Date: Fri, 28 Jan 2011 10:49:11 +0000 Subject: * libc/stdio/fclose.c: Only use sfp lock to guard non-atomic changes of flags and fp lock. * libc/stdio/freopen.c: Ditto. * libc/stdio/freopen64.c: Ditto. * libc/stdio/fgetc.c: Revert change from 2009-04-24, remove sfp locks which guard entire function to avoid potential deadlocks when using stdio functions in multiple thraeds. * libc/stdio/fgets.c: Ditto. * libc/stdio/fgetwc.c: Ditto. * libc/stdio/fgetws.c: Ditto. * libc/stdio/fread.c: Ditto. * libc/stdio/fseek.c: Ditto. * libc/stdio/getc.c: Ditto. * libc/stdio/getdelim.c: Ditto. * libc/stdio/gets.c: Ditto. * libc/stdio/vfscanf.c: Ditto. * libc/stdio/vfwscanf.c: Ditto. * libc/stdio/fflush.c (_fflush_r): Split out core functionality into new function __sflush_r. Just lock file and call __sflush_r from here. * libc/stdio/fwalk.c (_fwalk): Remove static helper function and move functionality back into main function. Don't walk a file with flags value of 1. Add comment. (_fwalk_reent): Ditto. * libc/stdio/local.h (__sflush_r): Declare. * libc/stdio/refill.c (__srefill): Before calling fwalk, set flags value to 1 so this file pointer isn't walked. Revert flags afterwards and call __sflush_r for this fp if necessary. Add comments. --- newlib/libc/stdio/refill.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'newlib/libc/stdio/refill.c') diff --git a/newlib/libc/stdio/refill.c b/newlib/libc/stdio/refill.c index 27266ce70..9d853f94d 100644 --- a/newlib/libc/stdio/refill.c +++ b/newlib/libc/stdio/refill.c @@ -102,9 +102,19 @@ _DEFUN(__srefill_r, (ptr, fp), * flush all line buffered output files, per the ANSI C * standard. */ - if (fp->_flags & (__SLBF | __SNBF)) - _CAST_VOID _fwalk (_GLOBAL_REENT, lflush); + { + /* Ignore this file in _fwalk to avoid potential deadlock. */ + short orig_flags = fp->_flags; + fp->_flags = 1; + _CAST_VOID _fwalk (_GLOBAL_REENT, lflush); + fp->_flags = orig_flags; + + /* Now flush this file without locking it. */ + if ((fp->_flags & (__SLBF|__SWR)) == (__SLBF|__SWR)) + __sflush_r (ptr, fp); + } + fp->_p = fp->_bf._base; fp->_r = fp->_read (ptr, fp->_cookie, (char *) fp->_p, fp->_bf._size); #ifndef __CYGWIN__ -- cgit v1.2.3