diff options
| -rw-r--r-- | libc/stdio/printf.c | 4 | ||||
| -rw-r--r-- | libc/stdio/scanf.c | 2 | ||||
| -rw-r--r-- | libc/stdio/stdio.c | 29 |
3 files changed, 26 insertions, 9 deletions
diff --git a/libc/stdio/printf.c b/libc/stdio/printf.c index 47c11c6bf..365cd41a2 100644 --- a/libc/stdio/printf.c +++ b/libc/stdio/printf.c @@ -61,6 +61,7 @@ #include <printf.h> #ifdef __STDIO_THREADSAFE +#include <stdio_ext.h> #include <pthread.h> #endif /* __STDIO_THREADSAFE */ @@ -1313,6 +1314,7 @@ int vsnprintf(char *__restrict buf, size_t size, #endif /* __STDIO_MBSTATE */ #ifdef __STDIO_THREADSAFE + f.user_locking = 0; __stdio_init_mutex(&f.lock); #endif @@ -1392,6 +1394,7 @@ int vsnprintf(char *__restrict buf, size_t size, #endif /* __STDIO_MBSTATE */ #ifdef __STDIO_THREADSAFE + f.user_locking = 0; __stdio_init_mutex(&f.lock); #endif @@ -1439,6 +1442,7 @@ int vdprintf(int filedes, const char * __restrict format, va_list arg) #endif /* __STDIO_MBSTATE */ #ifdef __STDIO_THREADSAFE + f.user_locking = 0; __stdio_init_mutex(&f.lock); #endif diff --git a/libc/stdio/scanf.c b/libc/stdio/scanf.c index 6d7a84e57..f392fe790 100644 --- a/libc/stdio/scanf.c +++ b/libc/stdio/scanf.c @@ -42,6 +42,7 @@ #include <stdarg.h> #ifdef __STDIO_THREADSAFE +#include <stdio_ext.h> #include <pthread.h> #endif /* __STDIO_THREADSAFE */ @@ -128,6 +129,7 @@ int vsscanf(__const char *sp, __const char *fmt, va_list ap) #endif /* __STDIO_MBSTATE */ #ifdef __STDIO_THREADSAFE + string->user_locking = 0; __stdio_init_mutex(&string->lock); #endif diff --git a/libc/stdio/stdio.c b/libc/stdio/stdio.c index 2c5f3bbed..bd6a7263c 100644 --- a/libc/stdio/stdio.c +++ b/libc/stdio/stdio.c @@ -1023,31 +1023,41 @@ void _flushlbf(void) /**********************************************************************/ #ifdef L___fsetlocking -/* No (serious) reentrancy issues -- return value could be incorrect. */ -/* TODO -- fix race */ +/* NOT threadsafe!!! (I don't think glibc's is either) + * + * This interacts badly with internal locking/unlocking. If you use this routine, + * make sure the file isn't being accessed by any other threads. Typical use would + * be to change to user locking immediately after opening the stream. + */ + +link_warning(__fsetlocking, "Oddly enough, __fsetlocking() is NOT threadsafe.") int __fsetlocking(FILE *stream, int locking_mode) { +#ifdef __STDIO_THREADSAFE int old_mode; +#endif assert((FSETLOCKING_QUERY == 0) && (FSETLOCKING_INTERNAL == 1) && (FSETLOCKING_BYCALLER == 2)); assert(((unsigned int) locking_mode) <= 2); - /* Note: don't even bother locking here... */ +#ifdef __STDIO_THREADSAFE + old_mode = stream->user_locking; - old_mode = stream->user_locking; + assert(((unsigned int) old_mode) <= 1); /* Must be 0 (internal) or 1 (user). */ if (locking_mode != FSETLOCKING_QUERY) { /* In case we're not debugging, treat any unknown as a request to * set internal locking, in order to match glibc behavior. */ - stream->user_locking = ((locking_mode == FSETLOCKING_BYCALLER) - ? FSETLOCKING_BYCALLER - : FSETLOCKING_INTERNAL); + stream->user_locking = (locking_mode == FSETLOCKING_BYCALLER); } - return old_mode; + return 2 - old_mode; +#else + return FSETLOCKING_BYCALLER; /* Well, without thread support... */ +#endif } #endif @@ -1851,7 +1861,7 @@ void _stdio_term(void) * Note: Set locking mode to "by caller" to save some overhead later. */ __stdio_init_mutex(&_stdio_openlist_lock); for (ptr = _stdio_openlist ; ptr ; ptr = ptr->nextopen ) { - ptr->user_locking = FSETLOCKING_BYCALLER; + ptr->user_locking = 1; __stdio_init_mutex(&ptr->lock); } #endif /* __STDIO_THREADSAFE */ @@ -2358,6 +2368,7 @@ FILE *_stdio_fopen(const char * __restrict filename, #endif /* __STDIO_MBSTATE */ #ifdef __STDIO_THREADSAFE + stream->user_locking = 0; __stdio_init_mutex(&stream->lock); #endif /* __STDIO_THREADSAFE */ |