GCOV - Varnish Cache


/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2007-2009 Dag-Erling Coïdan Smørgrav
 * All rights reserved.
 *
 * 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
 *    in this position and unchanged.
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 * Derived from:
 * $FreeBSD: head/lib/libutil/flopen.c 326219 2017-11-26 02:00:33Z pfg $
 */

#include "config.h"

#include <sys/file.h>
#include <sys/stat.h>

#include <errno.h>
#include <fcntl.h>      //lint !e537
#include <stdarg.h>
#include <unistd.h>

#include "vfl.h"

/*
 * Reliably open and lock a file.
 *
 * Please do not modify this code without first reading the revision history
 * and discussing your changes with <des@freebsd.org>.  Don't be fooled by the
 * code's apparent simplicity; there would be no need for this function if it
 * was easy to get right.
 */
static int
vflopenat(int dirfd, const char *path, int flags, va_list ap)
{
        int fd, operation, serrno, trunc;
        struct stat sb, fsb;
        mode_t mode;

#ifdef O_EXLOCK
        flags &= ~O_EXLOCK;
#endif

        mode = 0;
        if (flags & O_CREAT) {
                mode = (mode_t)va_arg(ap, int); /* mode_t promoted to int */
        }

        operation = LOCK_EX;
        if (flags & O_NONBLOCK)
                operation |= LOCK_NB;

        trunc = (flags & O_TRUNC);
        flags &= ~O_TRUNC;

        for (;;) {
                if ((fd = openat(dirfd, path, flags, mode)) == -1)
                        /* nonexistent or no access */
                        return (-1);
                if (flock(fd, operation) == -1) {
                        /* unsupported or interrupted */
                        serrno = errno;
                        (void)close(fd);
                        errno = serrno;
                        return (-1);
                }
                if (fstatat(dirfd, path, &sb, 0) == -1) {
                        /* disappeared from under our feet */
                        (void)close(fd);
                        continue;
                }
                if (fstat(fd, &fsb) == -1) {
                        /* can't happen [tm] */
                        serrno = errno;
                        (void)close(fd);
                        errno = serrno;
                        return (-1);
                }
                if (sb.st_dev != fsb.st_dev ||
                    sb.st_ino != fsb.st_ino) {
                        /* changed under our feet */
                        (void)close(fd);
                        continue;
                }
                if (trunc && ftruncate(fd, 0) != 0) {
                        /* can't happen [tm] */
                        serrno = errno;
                        (void)close(fd);
                        errno = serrno;
                        return (-1);
                }
                /*
                 * The following change is provided as a specific example to
                 * avoid.
                 */
#if 0
                if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0) {
                        serrno = errno;
                        (void)close(fd);
                        errno = serrno;
                        return (-1);
                }
#endif
                return (fd);
        }
}

int
VFL_Open(const char *path, int flags, ...)
{
        va_list ap;
        int ret;

        va_start(ap, flags);
        ret = vflopenat(AT_FDCWD, path, flags, ap);
        va_end(ap);
        return (ret);
}

		varnish-cache/lib/libvarnish/vfl.c
0		/*-
1		* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
2		*
3		* Copyright (c) 2007-2009 Dag-Erling Coïdan Smørgrav
4		* All rights reserved.
5		*
6		* Redistribution and use in source and binary forms, with or without
7		* modification, are permitted provided that the following conditions
8		* are met:
9		* 1. Redistributions of source code must retain the above copyright
10		* notice, this list of conditions and the following disclaimer
11		* in this position and unchanged.
12		* 2. Redistributions in binary form must reproduce the above copyright
13		* notice, this list of conditions and the following disclaimer in the
14		* documentation and/or other materials provided with the distribution.
15		*
16		* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17		* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18		* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19		* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20		* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21		* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22		* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23		* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24		* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25		* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26		* SUCH DAMAGE.
27		* Derived from:
28		* $FreeBSD: head/lib/libutil/flopen.c 326219 2017-11-26 02:00:33Z pfg $
29		*/
30
31		#include "config.h"
32
33		#include <sys/file.h>
34		#include <sys/stat.h>
35
36		#include <errno.h>
37		#include <fcntl.h> //lint !e537
38		#include <stdarg.h>
39		#include <unistd.h>
40
41		#include "vfl.h"
42
43		/*
44		* Reliably open and lock a file.
45		*
46		* Please do not modify this code without first reading the revision history
47		* and discussing your changes with <des@freebsd.org>. Don't be fooled by the
48		* code's apparent simplicity; there would be no need for this function if it
49		* was easy to get right.
50		*/
51		static int
52	1918	vflopenat(int dirfd, const char *path, int flags, va_list ap)
53		{
54		int fd, operation, serrno, trunc;
55		struct stat sb, fsb;
56		mode_t mode;
57
58		#ifdef O_EXLOCK
59	1918	flags &= ~O_EXLOCK;
60		#endif
61
62	1918	mode = 0;
63	1918	if (flags & O_CREAT) {
64	1918	mode = (mode_t)va_arg(ap, int); /* mode_t promoted to int */
65	1918	}
66
67	1918	operation = LOCK_EX;
68	1918	if (flags & O_NONBLOCK)
69	1918	operation \|= LOCK_NB;
70
71	1918	trunc = (flags & O_TRUNC);
72	1918	flags &= ~O_TRUNC;
73
74	1918	for (;;) {
75	1918	if ((fd = openat(dirfd, path, flags, mode)) == -1)
76		/* nonexistent or no access */
77	1	return (-1);
78	1917	if (flock(fd, operation) == -1) {
79		/* unsupported or interrupted */
80	3	serrno = errno;
81	3	(void)close(fd);
82	3	errno = serrno;
83	3	return (-1);
84		}
85	1914	if (fstatat(dirfd, path, &sb, 0) == -1) {
86		/* disappeared from under our feet */
87	0	(void)close(fd);
88	0	continue;
89		}
90	1914	if (fstat(fd, &fsb) == -1) {
91		/* can't happen [tm] */
92	0	serrno = errno;
93	0	(void)close(fd);
94	0	errno = serrno;
95	0	return (-1);
96		}
97	1914	if (sb.st_dev != fsb.st_dev \|\|
98	1914	sb.st_ino != fsb.st_ino) {
99		/* changed under our feet */
100	0	(void)close(fd);
101	0	continue;
102		}
103	1914	if (trunc && ftruncate(fd, 0) != 0) {
104		/* can't happen [tm] */
105	0	serrno = errno;
106	0	(void)close(fd);
107	0	errno = serrno;
108	0	return (-1);
109		}
110		/*
111		* The following change is provided as a specific example to
112		* avoid.
113		*/
114		#if 0
115		if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0) {
116		serrno = errno;
117		(void)close(fd);
118		errno = serrno;
119		return (-1);
120		}
121		#endif
122	1914	return (fd);
123		}
124	1918	}
125
126		int
127	1918	VFL_Open(const char *path, int flags, ...)
128		{
129		va_list ap;
130		int ret;
131
132	1918	va_start(ap, flags);
133	1918	ret = vflopenat(AT_FDCWD, path, flags, ap);
134	1918	va_end(ap);
135	1918	return (ret);
136		}