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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.bin/rcs/buf.c	Lines:	60	97	61.9 %
Date:	2016-12-06	Branches:	14	40	35.0 %


/*	$OpenBSD: buf.c,v 1.26 2015/11/02 16:45:21 nicm Exp $	*/
/*
 * Copyright (c) 2003 Jean-Francois Brousseau <jfb@openbsd.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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``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 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.
 */

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

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "buf.h"
#include "xmalloc.h"
#include "worklist.h"

#define BUF_INCR	128

struct buf {
	/* buffer handle, buffer size, and data length */
	u_char	*cb_buf;
	size_t	 cb_size;
	size_t	 cb_len;
};

#define SIZE_LEFT(b)	(b->cb_size - b->cb_len)

static void	buf_grow(BUF *, size_t);

/*
 * Create a new buffer structure and return a pointer to it.  This structure
 * uses dynamically-allocated memory and must be freed with buf_free(), once
 * the buffer is no longer needed.
 */
BUF *
buf_alloc(size_t len)
{
	BUF *b;

	b = xmalloc(sizeof(*b));
	/* Postpone creation of zero-sized buffers */
	if (len > 0)
		b->cb_buf = xcalloc(1, len);
	else
		b->cb_buf = NULL;

	b->cb_size = len;
	b->cb_len = 0;

	return (b);
}

/*
 * Open the file specified by <path> and load all of its contents into a
 * buffer.
 * Returns the loaded buffer on success or NULL on failure.
 * Sets errno on error.
 */
BUF *
buf_load(const char *path)
{
	int fd;
	ssize_t ret;
	size_t len;
	u_char *bp;
	struct stat st;
	BUF *buf;

	buf = NULL;

	if ((fd = open(path, O_RDONLY, 0600)) == -1)
		goto out;

	if (fstat(fd, &st) == -1)
		goto out;

	if (st.st_size > SIZE_MAX) {
		errno = EFBIG;
		goto out;
	}
	buf = buf_alloc(st.st_size);
	for (bp = buf->cb_buf; ; bp += (size_t)ret) {
		len = SIZE_LEFT(buf);
		ret = read(fd, bp, len);
		if (ret == -1) {
			int saved_errno;

			saved_errno = errno;
			buf_free(buf);
			buf = NULL;
			errno = saved_errno;
			goto out;
		} else if (ret == 0)
			break;

		buf->cb_len += (size_t)ret;
	}

out:
	if (fd != -1) {
		int saved_errno;

		/* We may want to preserve errno here. */
		saved_errno = errno;
		(void)close(fd);
		errno = saved_errno;
	}

	return (buf);
}

void
buf_free(BUF *b)
{
	if (b == NULL)
		return;
	free(b->cb_buf);
	free(b);
}

/*
 * Free the buffer <b>'s structural information but do not free the contents
 * of the buffer.  Instead, they are returned and should be freed later using
 * free().
 */
void *
buf_release(BUF *b)
{
	void *tmp;

	tmp = b->cb_buf;
	free(b);
	return (tmp);
}

u_char *
buf_get(BUF *b)
{
	return (b->cb_buf);
}

/*
 * Empty the contents of the buffer <b> and reset pointers.
 */
void
buf_empty(BUF *b)
{
	memset(b->cb_buf, 0, b->cb_size);
	b->cb_len = 0;
}

/*
 * Append a single character <c> to the end of the buffer <b>.
 */
void
buf_putc(BUF *b, int c)
{
	u_char *bp;

	if (SIZE_LEFT(b) == 0)
		buf_grow(b, BUF_INCR);
	bp = b->cb_buf + b->cb_len;
	*bp = (u_char)c;
	b->cb_len++;
}

/*
 * Append a string <s> to the end of buffer <b>.
 */
void
buf_puts(BUF *b, const char *str)
{
	buf_append(b, str, strlen(str));
}

/*
 * Return u_char at buffer position <pos>.
 */
u_char
buf_getc(BUF *b, size_t pos)
{
	return (b->cb_buf[pos]);
}

/*
 * Append <len> bytes of data pointed to by <data> to the buffer <b>.  If the
 * buffer is too small to accept all data, it will get resized to an
 * appropriate size to accept all data.
 * Returns the number of bytes successfully appended to the buffer.
 */
size_t
buf_append(BUF *b, const void *data, size_t len)
{
	size_t left, rlen;
	u_char *bp;

	left = SIZE_LEFT(b);
	rlen = len;

	if (left < len)
		buf_grow(b, len - left);
	bp = b->cb_buf + b->cb_len;
	memcpy(bp, data, rlen);
	b->cb_len += rlen;

	return (rlen);
}

/*
 * Returns the size of the buffer that is being used.
 */
size_t
buf_len(BUF *b)
{
	return (b->cb_len);
}

/*
 * Write the contents of the buffer <b> to the specified <fd>
 */
int
buf_write_fd(BUF *b, int fd)
{
	u_char *bp;
	size_t len;
	ssize_t ret;

	len = b->cb_len;
	bp = b->cb_buf;

	do {
		ret = write(fd, bp, len);
		if (ret == -1) {
			if (errno == EINTR || errno == EAGAIN)
				continue;
			return (-1);
		}

		len -= (size_t)ret;
		bp += (size_t)ret;
	} while (len > 0);

	return (0);
}

/*
 * Write the contents of the buffer <b> to the file whose path is given in
 * <path>.  If the file does not exist, it is created with mode <mode>.
 */
int
buf_write(BUF *b, const char *path, mode_t mode)
{
	int fd;
 open:
	if ((fd = open(path, O_WRONLY|O_CREAT|O_TRUNC, mode)) == -1) {
		if (errno == EACCES && unlink(path) != -1)
			goto open;
		else
			err(1, "%s", path);
	}

	if (buf_write_fd(b, fd) == -1) {
		(void)unlink(path);
		errx(1, "buf_write: buf_write_fd: `%s'", path);
	}

	if (fchmod(fd, mode) < 0)
		warn("permissions not set on file %s", path);

	(void)close(fd);

	return (0);
}

/*
 * Write the contents of the buffer <b> to a temporary file whose path is
 * specified using <template> (see mkstemp.3).
 * NB. This function will modify <template>, as per mkstemp
 */
void
buf_write_stmp(BUF *b, char *template)
{
	int fd;

	if ((fd = mkstemp(template)) == -1)
		err(1, "%s", template);

	worklist_add(template, &temp_files);

	if (buf_write_fd(b, fd) == -1) {
		(void)unlink(template);
		errx(1, "buf_write_stmp: buf_write_fd: `%s'", template);
	}

	(void)close(fd);
}

/*
 * Grow the buffer <b> by <len> bytes.  The contents are unchanged by this
 * operation regardless of the result.
 */
static void
buf_grow(BUF *b, size_t len)
{
	b->cb_buf = xreallocarray(b->cb_buf, 1, b->cb_size + len);
	b->cb_size += len;
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: buf.c,v 1.26 2015/11/02 16:45:21 nicm Exp $ */
2			/*
3			* Copyright (c) 2003 Jean-Francois Brousseau <jfb@openbsd.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			*
10			* 1. Redistributions of source code must retain the above copyright
11			* notice, this list of conditions and the following disclaimer.
12			* 2. The name of the author may not be used to endorse or promote products
13			* derived from this software without specific prior written permission.
14			*
15			* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
16			* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
17			* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
18			* THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19			* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20			* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
21			* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
22			* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
23			* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
24			* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25			*/
26
27			#include <sys/queue.h>
28			#include <sys/stat.h>
29
30			#include <err.h>
31			#include <errno.h>
32			#include <fcntl.h>
33			#include <stdint.h>
34			#include <stdio.h>
35			#include <stdlib.h>
36			#include <string.h>
37			#include <unistd.h>
38
39			#include "buf.h"
40			#include "xmalloc.h"
41			#include "worklist.h"
42
43			#define BUF_INCR 128
44
45			struct buf {
46			/* buffer handle, buffer size, and data length */
47			u_char *cb_buf;
48			size_t cb_size;
49			size_t cb_len;
50			};
51
52			#define SIZE_LEFT(b) (b->cb_size - b->cb_len)
53
54			static void buf_grow(BUF *, size_t);
55
56			/*
57			* Create a new buffer structure and return a pointer to it. This structure
58			* uses dynamically-allocated memory and must be freed with buf_free(), once
59			* the buffer is no longer needed.
60			*/
61			BUF *
62			buf_alloc(size_t len)
63		7	{
64			BUF *b;
65
66		7	b = xmalloc(sizeof(*b));
67			/* Postpone creation of zero-sized buffers */
68	✓✗	7	if (len > 0)
69		7	b->cb_buf = xcalloc(1, len);
70			else
71			b->cb_buf = NULL;
72
73		7	b->cb_size = len;
74		7	b->cb_len = 0;
75
76		7	return (b);
77			}
78
79			/*
80			* Open the file specified by <path> and load all of its contents into a
81			* buffer.
82			* Returns the loaded buffer on success or NULL on failure.
83			* Sets errno on error.
84			*/
85			BUF *
86			buf_load(const char *path)
87		3	{
88			int fd;
89			ssize_t ret;
90			size_t len;
91			u_char *bp;
92			struct stat st;
93			BUF *buf;
94
95		3	buf = NULL;
96
97	✓✗	3	if ((fd = open(path, O_RDONLY, 0600)) == -1)
98			goto out;
99
100	✗✓	3	if (fstat(fd, &st) == -1)
101			goto out;
102
103			if (st.st_size > SIZE_MAX) {
104			errno = EFBIG;
105			goto out;
106			}
107		3	buf = buf_alloc(st.st_size);
108		6	for (bp = buf->cb_buf; ; bp += (size_t)ret) {
109		6	len = SIZE_LEFT(buf);
110		6	ret = read(fd, bp, len);
111	✗✓	6	if (ret == -1) {
112			int saved_errno;
113
114			saved_errno = errno;
115			buf_free(buf);
116			buf = NULL;
117			errno = saved_errno;
118			goto out;
119	✓✓	6	} else if (ret == 0)
120		3	break;
121
122		3	buf->cb_len += (size_t)ret;
123		3	}
124
125		3	out:
126	✓✗	3	if (fd != -1) {
127			int saved_errno;
128
129			/* We may want to preserve errno here. */
130		3	saved_errno = errno;
131		3	(void)close(fd);
132		3	errno = saved_errno;
133			}
134
135		3	return (buf);
136			}
137
138			void
139			buf_free(BUF *b)
140		8	{
141	✓✓	8	if (b == NULL)
142		3	return;
143		5	free(b->cb_buf);
144		5	free(b);
145			}
146
147			/*
148			* Free the buffer <b>'s structural information but do not free the contents
149			* of the buffer. Instead, they are returned and should be freed later using
150			* free().
151			*/
152			void *
153			buf_release(BUF *b)
154		2	{
155			void *tmp;
156
157		2	tmp = b->cb_buf;
158		2	free(b);
159		2	return (tmp);
160			}
161
162			u_char *
163			buf_get(BUF *b)
164			{
165			return (b->cb_buf);
166			}
167
168			/*
169			* Empty the contents of the buffer <b> and reset pointers.
170			*/
171			void
172			buf_empty(BUF *b)
173			{
174			memset(b->cb_buf, 0, b->cb_size);
175			b->cb_len = 0;
176			}
177
178			/*
179			* Append a single character <c> to the end of the buffer <b>.
180			*/
181			void
182			buf_putc(BUF *b, int c)
183			{
184			u_char *bp;
185
186			if (SIZE_LEFT(b) == 0)
187			buf_grow(b, BUF_INCR);
188			bp = b->cb_buf + b->cb_len;
189			*bp = (u_char)c;
190			b->cb_len++;
191			}
192
193			/*
194			* Append a string <s> to the end of buffer <b>.
195			*/
196			void
197			buf_puts(BUF b, const char str)
198			{
199			buf_append(b, str, strlen(str));
200			}
201
202			/*
203			* Return u_char at buffer position <pos>.
204			*/
205			u_char
206			buf_getc(BUF *b, size_t pos)
207			{
208			return (b->cb_buf[pos]);
209			}
210
211			/*
212			* Append <len> bytes of data pointed to by <data> to the buffer <b>. If the
213			* buffer is too small to accept all data, it will get resized to an
214			* appropriate size to accept all data.
215			* Returns the number of bytes successfully appended to the buffer.
216			*/
217			size_t
218			buf_append(BUF b, const void data, size_t len)
219		10	{
220			size_t left, rlen;
221			u_char *bp;
222
223		10	left = SIZE_LEFT(b);
224		10	rlen = len;
225
226	✗✓	10	if (left < len)
227			buf_grow(b, len - left);
228		10	bp = b->cb_buf + b->cb_len;
229		10	memcpy(bp, data, rlen);
230		10	b->cb_len += rlen;
231
232		10	return (rlen);
233			}
234
235			/*
236			* Returns the size of the buffer that is being used.
237			*/
238			size_t
239			buf_len(BUF *b)
240		2	{
241		2	return (b->cb_len);
242			}
243
244			/*
245			* Write the contents of the buffer <b> to the specified <fd>
246			*/
247			int
248			buf_write_fd(BUF *b, int fd)
249		6	{
250			u_char *bp;
251			size_t len;
252			ssize_t ret;
253
254		6	len = b->cb_len;
255		6	bp = b->cb_buf;
256
257			do {
258		6	ret = write(fd, bp, len);
259	✗✓	6	if (ret == -1) {
260			if (errno == EINTR \|\| errno == EAGAIN)
261			continue;
262			return (-1);
263			}
264
265		6	len -= (size_t)ret;
266		6	bp += (size_t)ret;
267	✗✓	6	} while (len > 0);
268
269		6	return (0);
270			}
271
272			/*
273			* Write the contents of the buffer <b> to the file whose path is given in
274			* <path>. If the file does not exist, it is created with mode <mode>.
275			*/
276			int
277			buf_write(BUF b, const char path, mode_t mode)
278			{
279			int fd;
280			open:
281			if ((fd = open(path, O_WRONLY\|O_CREAT\|O_TRUNC, mode)) == -1) {
282			if (errno == EACCES && unlink(path) != -1)
283			goto open;
284			else
285			err(1, "%s", path);
286			}
287
288			if (buf_write_fd(b, fd) == -1) {
289			(void)unlink(path);
290			errx(1, "buf_write: buf_write_fd: `%s'", path);
291			}
292
293			if (fchmod(fd, mode) < 0)
294			warn("permissions not set on file %s", path);
295
296			(void)close(fd);
297
298			return (0);
299			}
300
301			/*
302			* Write the contents of the buffer <b> to a temporary file whose path is
303			* specified using <template> (see mkstemp.3).
304			* NB. This function will modify <template>, as per mkstemp
305			*/
306			void
307			buf_write_stmp(BUF b, char template)
308		5	{
309			int fd;
310
311	✗✓	5	if ((fd = mkstemp(template)) == -1)
312			err(1, "%s", template);
313
314		5	worklist_add(template, &temp_files);
315
316	✗✓	5	if (buf_write_fd(b, fd) == -1) {
317			(void)unlink(template);
318			errx(1, "buf_write_stmp: buf_write_fd: `%s'", template);
319			}
320
321		5	(void)close(fd);
322		5	}
323
324			/*
325			* Grow the buffer <b> by <len> bytes. The contents are unchanged by this
326			* operation regardless of the result.
327			*/
328			static void
329			buf_grow(BUF *b, size_t len)
330			{
331			b->cb_buf = xreallocarray(b->cb_buf, 1, b->cb_size + len);
332			b->cb_size += len;
333			}