GCOV - Varnish Cache


/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
 * 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.
 * 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 AUTHORS 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 AUTHORS 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/pidfile.c 184091 2008-10-20 17:41:08Z des $
 */

#include "config.h"

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

#include <fcntl.h>      //lint !e537
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "vdef.h"

#include "vas.h"        // XXX Flexelint "not used" - but req'ed for assert()
#include "vfl.h"
#include "vpf.h"

struct vpf_fh {
        int     pf_fd;
        char    *pf_path;
        dev_t   pf_dev;
        ino_t   pf_ino;
};

static int
vpf_verify(const struct vpf_fh *pfh)
{
        struct stat sb;

        if (pfh == NULL || pfh->pf_fd == -1)
                return (EINVAL);
        /*
         * Check remembered descriptor.
         */
        if (fstat(pfh->pf_fd, &sb) == -1)
                return (errno);
        if (sb.st_dev != pfh->pf_dev || sb.st_ino != pfh->pf_ino)
                return (EINVAL);
        return (0);
}

int
VPF_Read(const char *path, pid_t *pidptr)
{
        char buf[16], *endptr;
        int error, fd, i;

        fd = open(path, O_RDONLY | O_CLOEXEC);
        if (fd == -1)
                return (errno);

        i = read(fd, buf, sizeof(buf) - 1);
        error = errno;
        closefd(&fd);
        if (i == -1)
                return (error);
        else if (i == 0)
                return (EAGAIN);
        if (i > 0 && buf[i - 1] == '\n')
                i--;
        buf[i] = '\0';

        *pidptr = strtol(buf, &endptr, 10);
        if (endptr != &buf[i])
                return (EINVAL);

        return (0);
}

struct vpf_fh *
VPF_Open(const char *path, mode_t mode, pid_t *pidptr)
{
        struct vpf_fh *pfh;
        struct stat sb;
        int fd;

        /*
         * Open the PID file and obtain exclusive lock.
         * We truncate PID file here only to remove old PID immediately,
         * PID file will be truncated again in VPF_Write(), so
         * VPF_Write() can be called multiple times.
         */
        fd = VFL_Open(path,
            O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC | O_NONBLOCK, mode);
        if (fd == -1) {
                if (errno == EWOULDBLOCK && pidptr != NULL) {
                        errno = VPF_Read(path, pidptr);
                        if (errno == 0)
                                errno = EEXIST;
                }
                return (NULL);
        }

        /*
         * Remember file information, so in VPF_Write() we are sure we write
         * to the proper descriptor.
         */
        AZ(fstat(fd, &sb));

        pfh = malloc(sizeof(*pfh));
        AN(pfh);
        pfh->pf_path = strdup(path);
        AN(pfh->pf_path);

        pfh->pf_fd = fd;
        pfh->pf_dev = sb.st_dev;
        pfh->pf_ino = sb.st_ino;

        return (pfh);
}

void
VPF_Write(const struct vpf_fh *pfh)
{
        char pidstr[16];

        /*
         * Check remembered descriptor, so we don't overwrite some other
         * file if pidfile was closed and descriptor reused.
         */
        if (vpf_verify(pfh) != 0)
                return;

        /*
         * Truncate PID file, so multiple calls of VPF_Write() are allowed.
         */
        AZ(ftruncate(pfh->pf_fd, 0));

        bprintf(pidstr, "%jd", (intmax_t)getpid());
        assert(pwrite(pfh->pf_fd, pidstr, strlen(pidstr), 0) ==
            (ssize_t)strlen(pidstr));
}

void
VPF_Remove(struct vpf_fh *pfh)
{
        if (vpf_verify(pfh) == 0) {
                (void)unlink(pfh->pf_path);
                closefd(&pfh->pf_fd);
        }
        free(pfh->pf_path);
        free(pfh);
}

		varnish-cache/lib/libvarnish/vpf.c
0		/*-
1		* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
2		*
3		* Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
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		* 2. Redistributions in binary form must reproduce the above copyright
12		* notice, this list of conditions and the following disclaimer in the
13		* documentation and/or other materials provided with the distribution.
14		*
15		* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16		* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17		* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18		* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19		* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20		* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21		* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22		* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23		* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24		* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25		* SUCH DAMAGE.
26		* Derived from:
27		* $FreeBSD: head/lib/libutil/pidfile.c 184091 2008-10-20 17:41:08Z des $
28		*/
29
30		#include "config.h"
31
32		#include <sys/param.h>
33		#include <sys/file.h>
34		#include <sys/stat.h>
35
36		#include <fcntl.h> //lint !e537
37		#include <stdint.h>
38		#include <stdio.h>
39		#include <stdlib.h>
40		#include <string.h>
41		#include <unistd.h>
42
43		#include "vdef.h"
44
45		#include "vas.h" // XXX Flexelint "not used" - but req'ed for assert()
46		#include "vfl.h"
47		#include "vpf.h"
48
49		struct vpf_fh {
50		int pf_fd;
51		char *pf_path;
52		dev_t pf_dev;
53		ino_t pf_ino;
54		};
55
56		static int
57	3816	vpf_verify(const struct vpf_fh *pfh)
58		{
59		struct stat sb;
60
61	3816	if (pfh == NULL \|\| pfh->pf_fd == -1)
62	0	return (EINVAL);
63		/*
64		* Check remembered descriptor.
65		*/
66	3816	if (fstat(pfh->pf_fd, &sb) == -1)
67	0	return (errno);
68	3816	if (sb.st_dev != pfh->pf_dev \|\| sb.st_ino != pfh->pf_ino)
69	0	return (EINVAL);
70	3816	return (0);
71	3816	}
72
73		int
74	110	VPF_Read(const char path, pid_t pidptr)
75		{
76		char buf[16], *endptr;
77		int error, fd, i;
78
79	110	fd = open(path, O_RDONLY \| O_CLOEXEC);
80	110	if (fd == -1)
81	96	return (errno);
82
83	14	i = read(fd, buf, sizeof(buf) - 1);
84	14	error = errno;
85	14	closefd(&fd);
86	14	if (i == -1)
87	0	return (error);
88	14	else if (i == 0)
89	8	return (EAGAIN);
90	6	if (i > 0 && buf[i - 1] == '\n')
91	3	i--;
92	6	buf[i] = '\0';
93
94	6	*pidptr = strtol(buf, &endptr, 10);
95	6	if (endptr != &buf[i])
96	0	return (EINVAL);
97
98	6	return (0);
99	110	}
100
101		struct vpf_fh *
102	1918	VPF_Open(const char path, mode_t mode, pid_t pidptr)
103		{
104		struct vpf_fh *pfh;
105		struct stat sb;
106		int fd;
107
108		/*
109		* Open the PID file and obtain exclusive lock.
110		* We truncate PID file here only to remove old PID immediately,
111		* PID file will be truncated again in VPF_Write(), so
112		* VPF_Write() can be called multiple times.
113		*/
114	3836	fd = VFL_Open(path,
115	1918	O_WRONLY \| O_CREAT \| O_TRUNC \| O_CLOEXEC \| O_NONBLOCK, mode);
116	1918	if (fd == -1) {
117	4	if (errno == EWOULDBLOCK && pidptr != NULL) {
118	3	errno = VPF_Read(path, pidptr);
119	3	if (errno == 0)
120	3	errno = EEXIST;
121	3	}
122	4	return (NULL);
123		}
124
125		/*
126		* Remember file information, so in VPF_Write() we are sure we write
127		* to the proper descriptor.
128		*/
129	1914	AZ(fstat(fd, &sb));
130
131	1914	pfh = malloc(sizeof(*pfh));
132	1914	AN(pfh);
133	1914	pfh->pf_path = strdup(path);
134	1914	AN(pfh->pf_path);
135
136	1914	pfh->pf_fd = fd;
137	1914	pfh->pf_dev = sb.st_dev;
138	1914	pfh->pf_ino = sb.st_ino;
139
140	1914	return (pfh);
141	1918	}
142
143		void
144	1914	VPF_Write(const struct vpf_fh *pfh)
145		{
146		char pidstr[16];
147
148		/*
149		* Check remembered descriptor, so we don't overwrite some other
150		* file if pidfile was closed and descriptor reused.
151		*/
152	1914	if (vpf_verify(pfh) != 0)
153	0	return;
154
155		/*
156		* Truncate PID file, so multiple calls of VPF_Write() are allowed.
157		*/
158	1914	AZ(ftruncate(pfh->pf_fd, 0));
159
160	1914	bprintf(pidstr, "%jd", (intmax_t)getpid());
161	1914	assert(pwrite(pfh->pf_fd, pidstr, strlen(pidstr), 0) ==
162		(ssize_t)strlen(pidstr));
163	1914	}
164
165		void
166	1902	VPF_Remove(struct vpf_fh *pfh)
167		{
168	1902	if (vpf_verify(pfh) == 0) {
169	1902	(void)unlink(pfh->pf_path);
170	1902	closefd(&pfh->pf_fd);
171	1902	}
172	1902	free(pfh->pf_path);
173	1902	free(pfh);
174	1902	}