freebsd-dev/lib/libc/stdio/local.h
David Xu 3b52e4d1b7 With current pthread implementations, a mutex initialization will
allocate a memory block. sscanf calls __svfscanf which in turn calls
fread, fread triggers mutex initialization but the mutex is not
destroyed in sscanf, this leads to memory leak. To avoid the memory
leak and performance issue, we create a none MT-safe version of fread:
__fread, and instead let __svfscanf call __fread.

PR: threads/90392
Patch submitted by: dhartmei
MFC after: 7 days
2005-12-16 02:50:53 +00:00

142 lines
5.1 KiB
C

/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)local.h 8.3 (Berkeley) 7/3/94
* $FreeBSD$
*/
#include <sys/types.h> /* for off_t */
#include <pthread.h>
#include <string.h>
#include <wchar.h>
/*
* Information local to this implementation of stdio,
* in particular, macros and private variables.
*/
extern int _sread(FILE *, char *, int);
extern int _swrite(FILE *, char const *, int);
extern fpos_t _sseek(FILE *, fpos_t, int);
extern int _ftello(FILE *, fpos_t *);
extern int _fseeko(FILE *, off_t, int, int);
extern int __fflush(FILE *fp);
extern wint_t __fgetwc(FILE *);
extern wint_t __fputwc(wchar_t, FILE *);
extern int __sflush(FILE *);
extern FILE *__sfp(void);
extern int __slbexpand(FILE *, size_t);
extern int __srefill(FILE *);
extern int __sread(void *, char *, int);
extern int __swrite(void *, char const *, int);
extern fpos_t __sseek(void *, fpos_t, int);
extern int __sclose(void *);
extern void __sinit(void);
extern void _cleanup(void);
extern void __smakebuf(FILE *);
extern int __swhatbuf(FILE *, size_t *, int *);
extern int _fwalk(int (*)(FILE *));
extern int __svfscanf(FILE *, const char *, __va_list);
extern int __swsetup(FILE *);
extern int __sflags(const char *, int *);
extern int __ungetc(int, FILE *);
extern wint_t __ungetwc(wint_t, FILE *);
extern int __vfprintf(FILE *, const char *, __va_list);
extern int __vfscanf(FILE *, const char *, __va_list);
extern int __vfwprintf(FILE *, const wchar_t *, __va_list);
extern int __vfwscanf(FILE * __restrict, const wchar_t * __restrict,
__va_list);
extern size_t __fread(void * __restrict buf, size_t size, size_t count,
FILE * __restrict fp);
extern int __sdidinit;
/* hold a buncha junk that would grow the ABI */
struct __sFILEX {
unsigned char *_up; /* saved _p when _p is doing ungetc data */
pthread_mutex_t fl_mutex; /* used for MT-safety */
pthread_t fl_owner; /* current owner */
int fl_count; /* recursive lock count */
int orientation; /* orientation for fwide() */
mbstate_t mbstate; /* multibyte conversion state */
};
/*
* Prepare the given FILE for writing, and return 0 iff it
* can be written now. Otherwise, return EOF and set errno.
*/
#define prepwrite(fp) \
((((fp)->_flags & __SWR) == 0 || \
((fp)->_bf._base == NULL && ((fp)->_flags & __SSTR) == 0)) && \
__swsetup(fp))
/*
* Test whether the given stdio file has an active ungetc buffer;
* release such a buffer, without restoring ordinary unread data.
*/
#define HASUB(fp) ((fp)->_ub._base != NULL)
#define FREEUB(fp) { \
if ((fp)->_ub._base != (fp)->_ubuf) \
free((char *)(fp)->_ub._base); \
(fp)->_ub._base = NULL; \
}
/*
* test for an fgetln() buffer.
*/
#define HASLB(fp) ((fp)->_lb._base != NULL)
#define FREELB(fp) { \
free((char *)(fp)->_lb._base); \
(fp)->_lb._base = NULL; \
}
#define INITEXTRA(fp) { \
(fp)->_extra->_up = NULL; \
(fp)->_extra->fl_mutex = PTHREAD_MUTEX_INITIALIZER; \
(fp)->_extra->fl_owner = NULL; \
(fp)->_extra->fl_count = 0; \
(fp)->_extra->orientation = 0; \
memset(&(fp)->_extra->mbstate, 0, sizeof(mbstate_t)); \
}
/*
* Set the orientation for a stream. If o > 0, the stream has wide-
* orientation. If o < 0, the stream has byte-orientation.
*/
#define ORIENT(fp, o) do { \
if ((fp)->_extra->orientation == 0) \
(fp)->_extra->orientation = (o); \
} while (0)