* 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.
static char sccsid[] = "@(#)findfp.c 8.2 (Berkeley) 1/4/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/stdio/findfp.c,v 1.28 2002/11/14 14:06:14 imp Exp $");
+__FBSDID("$FreeBSD: src/lib/libc/stdio/findfp.c,v 1.34 2009/12/05 19:31:38 ed Exp $");
+
+#include <TargetConditionals.h>
#include <sys/param.h>
#include <machine/atomic.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <libkern/OSAtomic.h>
+#include <errno.h>
+#include <pthread.h>
#include <spinlock.h>
#include "libc_private.h"
#include "local.h"
#include "glue.h"
-int __sdidinit;
+pthread_once_t __sdidinit;
+#if !TARGET_OS_EMBEDDED
#define NDYNAMIC 10 /* add ten more whenever necessary */
+#else
+#define NDYNAMIC 1 /* add one at a time on embedded */
+#endif
+
+#define std(flags, file) { \
+ ._flags = (flags), \
+ ._file = (file), \
+ ._cookie = __sF + (file), \
+ ._close = __sclose, \
+ ._read = __sread, \
+ ._seek = __sseek, \
+ ._write = __swrite, \
+ ._extra = __sFX + file, \
+}
+ /* set counted */
+#define __sFXInit3 {.fl_mutex = PTHREAD_RECURSIVE_MUTEX_INITIALIZER, .counted = 1}
+
+static int __scounted; /* streams counted against STREAM_MAX */
+static int __stream_max;
-#define std(flags, file) \
- {0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite, \
- {0}, __sFX + file}
- /* p r w flags file _bf z cookie close read seek write */
- /* _ub _extra */
+#if !TARGET_OS_EMBEDDED
+/* usual and usual_extra are data pigs. See 7929728. For embedded we should
+ * always allocate dynamically, and probably should for desktop too. */
/* the usual - (stdin + stdout + stderr) */
static FILE usual[FOPEN_MAX - 3];
static struct __sFILEX usual_extra[FOPEN_MAX - 3];
static struct glue uglue = { NULL, FOPEN_MAX - 3, usual };
+#endif /* !TARGET_OS_EMBEDDED */
-static struct __sFILEX __sFX[3];
+static struct __sFILEX __sFX[3] = {__sFXInit3, __sFXInit3, __sFXInit3};
/*
- * We can't make this 'static' until 6.0-current due to binary
- * compatibility concerns. This also means we cannot change the
- * sizeof(FILE) until that time either and must continue to use the
- * __sFILEX stuff to add to FILE.
+ * We can't make this 'static' due to binary compatibility concerns.
+ * This also means we cannot change the sizeof(FILE) and must continue to
+ * use the __sFILEX stuff to add to FILE.
*/
FILE __sF[3] = {
std(__SRD, STDIN_FILENO),
std(__SWR|__SNBF, STDERR_FILENO)
};
-/*
- * The following kludge is done to ensure enough binary compatibility
- * with future versions of libc. Or rather it allows us to work with
- * libraries that have been built with a newer libc that defines these
- * symbols and expects libc to provide them. We only have need to support
- * i386 and alpha because they are the only "old" systems we have deployed.
- */
FILE *__stdinp = &__sF[0];
FILE *__stdoutp = &__sF[1];
FILE *__stderrp = &__sF[2];
+#if !TARGET_OS_EMBEDDED
struct glue __sglue = { &uglue, 3, __sF };
static struct glue *lastglue = &uglue;
+#else
+struct glue __sglue = { NULL, 3, __sF };
+static struct glue *lastglue = &__sglue;
+#endif
static struct glue * moreglue(int);
-static spinlock_t thread_lock = _SPINLOCK_INITIALIZER;
-#define THREAD_LOCK() if (__isthreaded) _SPINLOCK(&thread_lock)
-#define THREAD_UNLOCK() if (__isthreaded) _SPINUNLOCK(&thread_lock)
-
-#if NOT_YET
-#define SET_GLUE_PTR(ptr, val) atomic_set_rel_ptr(&(ptr), (uintptr_t)(val))
-#else
-#define SET_GLUE_PTR(ptr, val) ptr = val
-#endif
+static pthread_mutex_t filelist_lock = PTHREAD_MUTEX_INITIALIZER;
+#define FILELIST_LOCK() do { pthread_mutex_lock(&filelist_lock); } while(0)
+#define FILELIST_UNLOCK() do { pthread_mutex_unlock(&filelist_lock); } while(0)
static struct glue *
moreglue(n)
int n;
{
struct glue *g;
- static FILE empty;
- static struct __sFILEX emptyx;
FILE *p;
struct __sFILEX *fx;
g->next = NULL;
g->niobs = n;
g->iobs = p;
+
while (--n >= 0) {
- *p = empty;
+ bzero(p, sizeof(*p));
p->_extra = fx;
- *p->_extra = emptyx;
+ INITEXTRA(p);
p++, fx++;
}
return (g);
* Find a free FILE for fopen et al.
*/
FILE *
-__sfp()
+__sfp(int count)
{
FILE *fp;
int n;
struct glue *g;
- if (!__sdidinit)
- __sinit();
+ pthread_once(&__sdidinit, __sinit);
+
+ if (count) {
+ if (__scounted >= __stream_max) {
+ errno = EMFILE;
+ return NULL;
+ }
+ OSAtomicIncrement32(&__scounted);
+ }
/*
* The list must be locked because a FILE may be updated.
*/
- THREAD_LOCK();
+ FILELIST_LOCK();
for (g = &__sglue; g != NULL; g = g->next) {
for (fp = g->iobs, n = g->niobs; --n >= 0; fp++)
if (fp->_flags == 0)
goto found;
}
- THREAD_UNLOCK(); /* don't hold lock while malloc()ing. */
+ FILELIST_UNLOCK(); /* don't hold lock while malloc()ing. */
if ((g = moreglue(NDYNAMIC)) == NULL)
return (NULL);
- THREAD_LOCK(); /* reacquire the lock */
- SET_GLUE_PTR(lastglue->next, g); /* atomically append glue to list */
+ FILELIST_LOCK(); /* reacquire the lock */
+ lastglue->next = g; /* atomically append glue to list */
lastglue = g; /* not atomic; only accessed when locked */
fp = g->iobs;
found:
fp->_flags = 1; /* reserve this slot; caller sets real flags */
- THREAD_UNLOCK();
+ FILELIST_UNLOCK();
+
+ /* _flags = 1 means the FILE* is in use, and this thread owns the object while it is being initialized */
fp->_p = NULL; /* no current pointer */
fp->_w = 0; /* nothing to read or write */
fp->_r = 0;
fp->_lb._base = NULL; /* no line buffer */
fp->_lb._size = 0;
/* fp->_lock = NULL; */ /* once set always set (reused) */
- fp->_extra->orientation = 0;
-#ifdef notdef
- /* Stateful encoding/decoding is not yet supported. */
- memset(&fp->_extra->wstate, 0, sizeof(mbstate_t));
- memset(&fp->_extra->rstate, 0, sizeof(mbstate_t));
-#endif
+ INITEXTRA(fp);
+ fp->_extra->counted = count ? 1 : 0;
return (fp);
}
+/*
+ * Mark as free and update count as needed
+ */
+__private_extern__ void
+__sfprelease(FILE *fp)
+{
+ if (fp->_counted) {
+ OSAtomicDecrement32(&__scounted);
+ fp->_counted = 0;
+ }
+
+ pthread_mutex_destroy(&fp->_extra->fl_mutex);
+
+ /* Make sure nobody else is enumerating the list while we clear the "in use" _flags field. */
+ FILELIST_LOCK();
+ fp->_flags = 0;
+ FILELIST_UNLOCK();
+}
+
/*
* XXX. Force immediate allocation of internal memory. Not used by stdio,
* but documented historically for certain applications. Bad applications.
"warning: this program uses f_prealloc(), which is not recommended.");
void
-f_prealloc()
+f_prealloc(void)
{
struct glue *g;
int n;
for (g = &__sglue; (n -= g->niobs) > 0 && g->next; g = g->next)
/* void */;
if ((n > 0) && ((g = moreglue(n)) != NULL)) {
- THREAD_LOCK();
- SET_GLUE_PTR(lastglue->next, g);
+ FILELIST_LOCK();
+ lastglue->next = g;
lastglue = g;
- THREAD_UNLOCK();
+ FILELIST_UNLOCK();
}
}
void
__sinit()
{
- int i;
+#if !TARGET_OS_EMBEDDED
+ int i;
+#endif
- THREAD_LOCK();
- if (__sdidinit == 0) {
- /* Set _extra for the usual suspects. */
- for (i = 0; i < FOPEN_MAX - 3; i++)
- usual[i]._extra = &usual_extra[i];
+ /* Make sure we clean up on exit. */
+ __cleanup = _cleanup; /* conservative */
+ __stream_max = sysconf(_SC_STREAM_MAX);
+ __scounted = 3; /* std{in,out,err} already exists */
- /* Make sure we clean up on exit. */
- __cleanup = _cleanup; /* conservative */
- __sdidinit = 1;
+#if !TARGET_OS_EMBEDDED
+ /* Set _extra for the usual suspects. */
+ for (i = 0; i < FOPEN_MAX - 3; i++) {
+ usual[i]._extra = &usual_extra[i];
+ INITEXTRA(&usual[i]);
}
- THREAD_UNLOCK();
+#endif
}
projects / apple / libc.git / blobdiff