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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/librthread/rthread_sem.c	Lines:	100	187	53.5 %
Date:	2017-11-13	Branches:	60	130	46.2 %


/*	$OpenBSD: rthread_sem.c,v 1.26 2017/09/05 02:40:54 guenther Exp $ */
/*
 * Copyright (c) 2004,2005,2013 Ted Unangst <tedu@openbsd.org>
 * All Rights Reserved.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>

#include <errno.h>
#include <fcntl.h>
#include <sha2.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include <pthread.h>

#include "rthread.h"
#include "cancel.h"		/* in libc/include */

#define SHARED_IDENT ((void *)-1)

/* SHA256_DIGEST_STRING_LENGTH includes nul */
/* "/tmp/" + sha256 + ".sem" */
#define SEM_PATH_SIZE (5 + SHA256_DIGEST_STRING_LENGTH + 4)

/* long enough to be hard to guess */
#define SEM_RANDOM_NAME_LEN	10

/*
 * Size of memory to be mmap()'ed by named semaphores.
 * Should be >= SEM_PATH_SIZE and page-aligned.
 */
#define SEM_MMAP_SIZE	_thread_pagesize

/*
 * Internal implementation of semaphores
 */
int
_sem_wait(sem_t sem, int tryonly, const struct timespec *abstime,
    int *delayed_cancel)
{
	void *ident = (void *)&sem->waitcount;
	int r;

	if (sem->shared)
		ident = SHARED_IDENT;

	_spinlock(&sem->lock);
	if (sem->value) {
		sem->value--;
		r = 0;
	} else if (tryonly) {
		r = EAGAIN;
	} else {
		sem->waitcount++;
		do {
			r = __thrsleep(ident, CLOCK_REALTIME, abstime,
			    &sem->lock, delayed_cancel);
			_spinlock(&sem->lock);
			/* ignore interruptions other than cancelation */
			if (r == EINTR && (delayed_cancel == NULL ||
			    *delayed_cancel == 0))
				r = 0;
		} while (r == 0 && sem->value == 0);
		sem->waitcount--;
		if (r == 0)
			sem->value--;
	}
	_spinunlock(&sem->lock);
	return (r);
}

/* always increment count */
int
_sem_post(sem_t sem)
{
	void *ident = (void *)&sem->waitcount;
	int rv = 0;

	if (sem->shared)
		ident = SHARED_IDENT;

	_spinlock(&sem->lock);
	sem->value++;
	if (sem->waitcount) {
		__thrwakeup(ident, 1);
		rv = 1;
	}
	_spinunlock(&sem->lock);
	return (rv);
}

/*
 * exported semaphores
 */
int
sem_init(sem_t *semp, int pshared, unsigned int value)
{
	sem_t sem;

	if (value > SEM_VALUE_MAX) {
		errno = EINVAL;
		return (-1);
	}

	if (pshared) {
		errno = EPERM;
		return (-1);
#ifdef notyet
		char name[SEM_RANDOM_NAME_LEN];
		sem_t *sempshared;
		int i;

		for (;;) {
			for (i = 0; i < SEM_RANDOM_NAME_LEN - 1; i++)
				name[i] = arc4random_uniform(255) + 1;
			name[SEM_RANDOM_NAME_LEN - 1] = '\0';
			sempshared = sem_open(name, O_CREAT | O_EXCL, 0, value);
			if (sempshared != SEM_FAILED)
				break;
			if (errno == EEXIST)
				continue;
			if (errno != EPERM)
				errno = ENOSPC;
			return (-1);
		}

		/* unnamed semaphore should not be opened twice */
		if (sem_unlink(name) == -1) {
			sem_close(sempshared);
			errno = ENOSPC;
			return (-1);
		}

		*semp = *sempshared;
		free(sempshared);
		return (0);
#endif
	}

	sem = calloc(1, sizeof(*sem));
	if (!sem) {
		errno = ENOSPC;
		return (-1);
	}
	sem->lock = _SPINLOCK_UNLOCKED;
	sem->value = value;
	*semp = sem;

	return (0);
}

int
sem_destroy(sem_t *semp)
{
	sem_t sem;

	if (!_threads_ready)		 /* for SEM_MMAP_SIZE */
		_rthread_init();

	if (!semp || !(sem = *semp)) {
		errno = EINVAL;
		return (-1);
	}

	if (sem->waitcount) {
#define MSG "sem_destroy on semaphore with waiters!\n"
		write(2, MSG, sizeof(MSG) - 1);
#undef MSG
		errno = EBUSY;
		return (-1);
	}

	*semp = NULL;
	if (sem->shared)
		munmap(sem, SEM_MMAP_SIZE);
	else
		free(sem);

	return (0);
}

int
sem_getvalue(sem_t *semp, int *sval)
{
	sem_t sem;

	if (!semp || !(sem = *semp)) {
		errno = EINVAL;
		return (-1);
	}

	_spinlock(&sem->lock);
	*sval = sem->value;
	_spinunlock(&sem->lock);

	return (0);
}

int
sem_post(sem_t *semp)
{
	sem_t sem;

	if (!semp || !(sem = *semp)) {
		errno = EINVAL;
		return (-1);
	}

	_sem_post(sem);

	return (0);
}

int
sem_wait(sem_t *semp)
{
	struct tib *tib = TIB_GET();
	pthread_t self;
	sem_t sem;
	int r;
	PREP_CANCEL_POINT(tib);

	if (!_threads_ready)
		_rthread_init();
	self = tib->tib_thread;

	if (!semp || !(sem = *semp)) {
		errno = EINVAL;
		return (-1);
	}

	ENTER_DELAYED_CANCEL_POINT(tib, self);
	r = _sem_wait(sem, 0, NULL, &self->delayed_cancel);
	LEAVE_CANCEL_POINT_INNER(tib, r);

	if (r) {
		errno = r;
		return (-1);
	}

	return (0);
}

int
sem_timedwait(sem_t *semp, const struct timespec *abstime)
{
	struct tib *tib = TIB_GET();
	pthread_t self;
	sem_t sem;
	int r;
	PREP_CANCEL_POINT(tib);

	if (!_threads_ready)
		_rthread_init();
	self = tib->tib_thread;

	if (!semp || !(sem = *semp)) {
		errno = EINVAL;
		return (-1);
	}

	ENTER_DELAYED_CANCEL_POINT(tib, self);
	r = _sem_wait(sem, 0, abstime, &self->delayed_cancel);
	LEAVE_CANCEL_POINT_INNER(tib, r);

	if (r) {
		errno = r == EWOULDBLOCK ? ETIMEDOUT : r;
		return (-1);
	}

	return (0);
}

int
sem_trywait(sem_t *semp)
{
	sem_t sem;
	int r;

	if (!semp || !(sem = *semp)) {
		errno = EINVAL;
		return (-1);
	}

	r = _sem_wait(sem, 1, NULL, NULL);

	if (r) {
		errno = r;
		return (-1);
	}

	return (0);
}


static void
makesempath(const char *origpath, char *sempath, size_t len)
{
	char buf[SHA256_DIGEST_STRING_LENGTH];

	SHA256Data(origpath, strlen(origpath), buf);
	snprintf(sempath, len, "/tmp/%s.sem", buf);
}

sem_t *
sem_open(const char *name, int oflag, ...)
{
	char sempath[SEM_PATH_SIZE];
	struct stat sb;
	sem_t sem, *semp;
	unsigned int value = 0;
	int created = 0, fd;

	if (!_threads_ready)
		_rthread_init();

	if (oflag & ~(O_CREAT | O_EXCL)) {
		errno = EINVAL;
		return (SEM_FAILED);
	}

	if (oflag & O_CREAT) {
		va_list ap;
		va_start(ap, oflag);
		/* 3rd parameter mode is not used */
		va_arg(ap, mode_t);
		value = va_arg(ap, unsigned);
		va_end(ap);

		if (value > SEM_VALUE_MAX) {
			errno = EINVAL;
			return (SEM_FAILED);
		}
	}

	makesempath(name, sempath, sizeof(sempath));
	fd = open(sempath, O_RDWR | O_NOFOLLOW | oflag, 0600);
	if (fd == -1)
		return (SEM_FAILED);
	if (fstat(fd, &sb) == -1 || !S_ISREG(sb.st_mode)) {
		close(fd);
		errno = EINVAL;
		return (SEM_FAILED);
	}
	if (sb.st_uid != geteuid()) {
		close(fd);
		errno = EPERM;
		return (SEM_FAILED);
	}
	if (sb.st_size != (off_t)SEM_MMAP_SIZE) {
		if (!(oflag & O_CREAT)) {
			close(fd);
			errno = EINVAL;
			return (SEM_FAILED);
		}
		if (sb.st_size != 0) {
			close(fd);
			errno = EINVAL;
			return (SEM_FAILED);
		}
		if (ftruncate(fd, SEM_MMAP_SIZE) == -1) {
			close(fd);
			errno = EINVAL;
			return (SEM_FAILED);
		}

		created = 1;
	}
	sem = mmap(NULL, SEM_MMAP_SIZE, PROT_READ | PROT_WRITE,
	    MAP_SHARED, fd, 0);
	close(fd);
	if (sem == MAP_FAILED) {
		errno = EINVAL;
		return (SEM_FAILED);
	}
	semp = malloc(sizeof(*semp));
	if (!semp) {
		munmap(sem, SEM_MMAP_SIZE);
		errno = ENOSPC;
		return (SEM_FAILED);
	}
	if (created) {
		sem->lock = _SPINLOCK_UNLOCKED;
		sem->value = value;
		sem->shared = 1;
	}
	*semp = sem;

	return (semp);
}

int
sem_close(sem_t *semp)
{
	sem_t sem;

	if (!semp || !(sem = *semp) || !sem->shared) {
		errno = EINVAL;
		return (-1);
	}

	*semp = NULL;
	munmap(sem, SEM_MMAP_SIZE);
	free(semp);

	return (0);
}

int
sem_unlink(const char *name)
{
	char sempath[SEM_PATH_SIZE];

	makesempath(name, sempath, sizeof(sempath));
	return (unlink(sempath));
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: rthread_sem.c,v 1.26 2017/09/05 02:40:54 guenther Exp $ */
2			/*
3			* Copyright (c) 2004,2005,2013 Ted Unangst <tedu@openbsd.org>
4			* All Rights Reserved.
5			*
6			* Permission to use, copy, modify, and distribute this software for any
7			* purpose with or without fee is hereby granted, provided that the above
8			* copyright notice and this permission notice appear in all copies.
9			*
10			* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17			*/
18
19			#include <sys/types.h>
20			#include <sys/mman.h>
21			#include <sys/stat.h>
22
23			#include <errno.h>
24			#include <fcntl.h>
25			#include <sha2.h>
26			#include <stdarg.h>
27			#include <stdlib.h>
28			#include <stdio.h>
29			#include <string.h>
30			#include <unistd.h>
31
32			#include <pthread.h>
33
34			#include "rthread.h"
35			#include "cancel.h" /* in libc/include */
36
37			#define SHARED_IDENT ((void *)-1)
38
39			/* SHA256_DIGEST_STRING_LENGTH includes nul */
40			/* "/tmp/" + sha256 + ".sem" */
41			#define SEM_PATH_SIZE (5 + SHA256_DIGEST_STRING_LENGTH + 4)
42
43			/* long enough to be hard to guess */
44			#define SEM_RANDOM_NAME_LEN 10
45
46			/*
47			* Size of memory to be mmap()'ed by named semaphores.
48			* Should be >= SEM_PATH_SIZE and page-aligned.
49			*/
50			#define SEM_MMAP_SIZE _thread_pagesize
51
52			/*
53			* Internal implementation of semaphores
54			*/
55			int
56			_sem_wait(sem_t sem, int tryonly, const struct timespec *abstime,
57			int *delayed_cancel)
58			{
59		154988	void ident = (void )&sem->waitcount;
60			int r;
61
62	✗✓	77494	if (sem->shared)
63			ident = SHARED_IDENT;
64
65		77494	_spinlock(&sem->lock);
66	✓✓	77494	if (sem->value) {
67		76302	sem->value--;
68			r = 0;
69	✓✓	77494	} else if (tryonly) {
70			r = EAGAIN;
71		673	} else {
72		519	sem->waitcount++;
73		519	do {
74		533	r = __thrsleep(ident, CLOCK_REALTIME, abstime,
75		533	&sem->lock, delayed_cancel);
76		533	_spinlock(&sem->lock);
77			/* ignore interruptions other than cancelation */
78	✓✓✓✗ ✓✗	551	if (r == EINTR && (delayed_cancel == NULL \|\|
79		9	*delayed_cancel == 0))
80		9	r = 0;
81	✓✓✓✓	1063	} while (r == 0 && sem->value == 0);
82		519	sem->waitcount--;
83	✓✓	519	if (r == 0)
84		516	sem->value--;
85			}
86		77494	_spinunlock(&sem->lock);
87		77494	return (r);
88			}
89
90			/* always increment count */
91			int
92			_sem_post(sem_t sem)
93			{
94		156714	void ident = (void )&sem->waitcount;
95			int rv = 0;
96
97	✗✓	78357	if (sem->shared)
98			ident = SHARED_IDENT;
99
100		78357	_spinlock(&sem->lock);
101		78357	sem->value++;
102	✓✓	78357	if (sem->waitcount) {
103		540	__thrwakeup(ident, 1);
104			rv = 1;
105		540	}
106		78357	_spinunlock(&sem->lock);
107		78357	return (rv);
108			}
109
110			/*
111			* exported semaphores
112			*/
113			int
114			sem_init(sem_t *semp, int pshared, unsigned int value)
115			{
116			sem_t sem;
117
118	✗✓	2310	if (value > SEM_VALUE_MAX) {
119			errno = EINVAL;
120			return (-1);
121			}
122
123	✗✓	1155	if (pshared) {
124			errno = EPERM;
125			return (-1);
126			#ifdef notyet
127			char name[SEM_RANDOM_NAME_LEN];
128			sem_t *sempshared;
129			int i;
130
131			for (;;) {
132			for (i = 0; i < SEM_RANDOM_NAME_LEN - 1; i++)
133			name[i] = arc4random_uniform(255) + 1;
134			name[SEM_RANDOM_NAME_LEN - 1] = '\0';
135			sempshared = sem_open(name, O_CREAT \| O_EXCL, 0, value);
136			if (sempshared != SEM_FAILED)
137			break;
138			if (errno == EEXIST)
139			continue;
140			if (errno != EPERM)
141			errno = ENOSPC;
142			return (-1);
143			}
144
145			/* unnamed semaphore should not be opened twice */
146			if (sem_unlink(name) == -1) {
147			sem_close(sempshared);
148			errno = ENOSPC;
149			return (-1);
150			}
151
152			semp = sempshared;
153			free(sempshared);
154			return (0);
155			#endif
156			}
157
158		1155	sem = calloc(1, sizeof(*sem));
159	✗✓	1155	if (!sem) {
160			errno = ENOSPC;
161			return (-1);
162			}
163		1155	sem->lock = _SPINLOCK_UNLOCKED;
164		1155	sem->value = value;
165		1155	*semp = sem;
166
167		1155	return (0);
168		1155	}
169
170			int
171			sem_destroy(sem_t *semp)
172			{
173			sem_t sem;
174
175	✓✓	376	if (!_threads_ready) /* for SEM_MMAP_SIZE */
176		6	_rthread_init();
177
178	✓✗✗✓	376	if (!semp \|\| !(sem = *semp)) {
179			errno = EINVAL;
180			return (-1);
181			}
182
183	✓✓	188	if (sem->waitcount) {
184			#define MSG "sem_destroy on semaphore with waiters!\n"
185		6	write(2, MSG, sizeof(MSG) - 1);
186			#undef MSG
187		6	errno = EBUSY;
188		6	return (-1);
189			}
190
191		182	*semp = NULL;
192	✗✓	182	if (sem->shared)
193			munmap(sem, SEM_MMAP_SIZE);
194			else
195		182	free(sem);
196
197		182	return (0);
198		188	}
199
200			int
201			sem_getvalue(sem_t semp, int sval)
202			{
203			sem_t sem;
204
205	✓✗✗✓	63	if (!semp \|\| !(sem = *semp)) {
206			errno = EINVAL;
207			return (-1);
208			}
209
210		21	_spinlock(&sem->lock);
211		21	*sval = sem->value;
212		21	_spinunlock(&sem->lock);
213
214		21	return (0);
215		21	}
216
217			int
218			sem_post(sem_t *semp)
219			{
220			sem_t sem;
221
222	✓✗✗✓	215805	if (!semp \|\| !(sem = *semp)) {
223			errno = EINVAL;
224			return (-1);
225			}
226
227		71935	_sem_post(sem);
228
229		71935	return (0);
230		71935	}
231
232			int
233			sem_wait(sem_t *semp)
234			{
235		95886	struct tib *tib = TIB_GET();
236			pthread_t self;
237			sem_t sem;
238			int r;
239		47943	PREP_CANCEL_POINT(tib);
240
241	✓✓	47943	if (!_threads_ready)
242		25	_rthread_init();
243		47943	self = tib->tib_thread;
244
245	✓✗✓✓	95886	if (!semp \|\| !(sem = *semp)) {
246		3	errno = EINVAL;
247		3	return (-1);
248			}
249
250	✓✗✗✓	95880	ENTER_DELAYED_CANCEL_POINT(tib, self);
251		47940	r = _sem_wait(sem, 0, NULL, &self->delayed_cancel);
252	✓✗✗✓ ✗✗	95880	LEAVE_CANCEL_POINT_INNER(tib, r);
253
254	✗✓	47940	if (r) {
255			errno = r;
256			return (-1);
257			}
258
259		47940	return (0);
260		47943	}
261
262			int
263			sem_timedwait(sem_t semp, const struct timespec abstime)
264			{
265		24	struct tib *tib = TIB_GET();
266			pthread_t self;
267			sem_t sem;
268			int r;
269		12	PREP_CANCEL_POINT(tib);
270
271	✓✓	12	if (!_threads_ready)
272		3	_rthread_init();
273		12	self = tib->tib_thread;
274
275	✓✗✓✓	24	if (!semp \|\| !(sem = *semp)) {
276		3	errno = EINVAL;
277		3	return (-1);
278			}
279
280	✓✗✗✓	18	ENTER_DELAYED_CANCEL_POINT(tib, self);
281		9	r = _sem_wait(sem, 0, abstime, &self->delayed_cancel);
282	✓✗✓✓ ✗✓	21	LEAVE_CANCEL_POINT_INNER(tib, r);
283
284	✓✓	9	if (r) {
285		3	errno = r == EWOULDBLOCK ? ETIMEDOUT : r;
286		3	return (-1);
287			}
288
289		6	return (0);
290		12	}
291
292			int
293			sem_trywait(sem_t *semp)
294			{
295			sem_t sem;
296			int r;
297
298	✓✗✓✓	74046	if (!semp \|\| !(sem = *semp)) {
299		3	errno = EINVAL;
300		3	return (-1);
301			}
302
303		24679	r = _sem_wait(sem, 1, NULL, NULL);
304
305	✓✓	24679	if (r) {
306		673	errno = r;
307		673	return (-1);
308			}
309
310		24006	return (0);
311		24682	}
312
313
314			static void
315			makesempath(const char origpath, char sempath, size_t len)
316			{
317			char buf[SHA256_DIGEST_STRING_LENGTH];
318
319			SHA256Data(origpath, strlen(origpath), buf);
320			snprintf(sempath, len, "/tmp/%s.sem", buf);
321			}
322
323			sem_t *
324			sem_open(const char *name, int oflag, ...)
325			{
326			char sempath[SEM_PATH_SIZE];
327			struct stat sb;
328			sem_t sem, *semp;
329			unsigned int value = 0;
330			int created = 0, fd;
331
332			if (!_threads_ready)
333			_rthread_init();
334
335			if (oflag & ~(O_CREAT \| O_EXCL)) {
336			errno = EINVAL;
337			return (SEM_FAILED);
338			}
339
340			if (oflag & O_CREAT) {
341			va_list ap;
342			va_start(ap, oflag);
343			/* 3rd parameter mode is not used */
344			va_arg(ap, mode_t);
345			value = va_arg(ap, unsigned);
346			va_end(ap);
347
348			if (value > SEM_VALUE_MAX) {
349			errno = EINVAL;
350			return (SEM_FAILED);
351			}
352			}
353
354			makesempath(name, sempath, sizeof(sempath));
355			fd = open(sempath, O_RDWR \| O_NOFOLLOW \| oflag, 0600);
356			if (fd == -1)
357			return (SEM_FAILED);
358			if (fstat(fd, &sb) == -1 \|\| !S_ISREG(sb.st_mode)) {
359			close(fd);
360			errno = EINVAL;
361			return (SEM_FAILED);
362			}
363			if (sb.st_uid != geteuid()) {
364			close(fd);
365			errno = EPERM;
366			return (SEM_FAILED);
367			}
368			if (sb.st_size != (off_t)SEM_MMAP_SIZE) {
369			if (!(oflag & O_CREAT)) {
370			close(fd);
371			errno = EINVAL;
372			return (SEM_FAILED);
373			}
374			if (sb.st_size != 0) {
375			close(fd);
376			errno = EINVAL;
377			return (SEM_FAILED);
378			}
379			if (ftruncate(fd, SEM_MMAP_SIZE) == -1) {
380			close(fd);
381			errno = EINVAL;
382			return (SEM_FAILED);
383			}
384
385			created = 1;
386			}
387			sem = mmap(NULL, SEM_MMAP_SIZE, PROT_READ \| PROT_WRITE,
388			MAP_SHARED, fd, 0);
389			close(fd);
390			if (sem == MAP_FAILED) {
391			errno = EINVAL;
392			return (SEM_FAILED);
393			}
394			semp = malloc(sizeof(*semp));
395			if (!semp) {
396			munmap(sem, SEM_MMAP_SIZE);
397			errno = ENOSPC;
398			return (SEM_FAILED);
399			}
400			if (created) {
401			sem->lock = _SPINLOCK_UNLOCKED;
402			sem->value = value;
403			sem->shared = 1;
404			}
405			*semp = sem;
406
407			return (semp);
408			}
409
410			int
411			sem_close(sem_t *semp)
412			{
413			sem_t sem;
414
415			if (!semp \|\| !(sem = *semp) \|\| !sem->shared) {
416			errno = EINVAL;
417			return (-1);
418			}
419
420			*semp = NULL;
421			munmap(sem, SEM_MMAP_SIZE);
422			free(semp);
423
424			return (0);
425			}
426
427			int
428			sem_unlink(const char *name)
429			{
430			char sempath[SEM_PATH_SIZE];
431
432			makesempath(name, sempath, sizeof(sempath));
433			return (unlink(sempath));
434			}