Annotation of src/usr.bin/cvs/buf.c, Revision 1.69
1.69 ! joris 1: /* $OpenBSD: buf.c,v 1.68 2008/02/11 20:33:10 tobias Exp $ */
1.1 jfb 2: /*
1.2 jfb 3: * Copyright (c) 2003 Jean-Francois Brousseau <jfb@openbsd.org>
1.1 jfb 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:
1.60 otto 27: #include <sys/stat.h>
1.67 tobias 28: #include <sys/time.h>
1.60 otto 29:
30: #include <errno.h>
31: #include <fcntl.h>
1.66 chl 32: #include <stdlib.h>
1.60 otto 33: #include <string.h>
34: #include <unistd.h>
1.1 jfb 35:
1.65 tobias 36: #include "atomicio.h"
1.51 joris 37: #include "cvs.h"
1.1 jfb 38: #include "buf.h"
39:
1.15 xsa 40: #define BUF_INCR 128
1.1 jfb 41:
42: struct cvs_buf {
1.57 ray 43: /* buffer handle, buffer size, and data length */
1.15 xsa 44: u_char *cb_buf;
45: size_t cb_size;
46: size_t cb_len;
1.1 jfb 47: };
48:
1.57 ray 49: #define SIZE_LEFT(b) (b->cb_size - b->cb_len)
1.1 jfb 50:
1.46 ray 51: static void cvs_buf_grow(BUF *, size_t);
1.1 jfb 52:
53: /*
54: * cvs_buf_alloc()
55: *
56: * Create a new buffer structure and return a pointer to it. This structure
57: * uses dynamically-allocated memory and must be freed with cvs_buf_free(),
58: * once the buffer is no longer needed.
59: */
1.15 xsa 60: BUF *
1.68 tobias 61: cvs_buf_alloc(size_t len)
1.1 jfb 62: {
63: BUF *b;
64:
1.42 ray 65: b = xmalloc(sizeof(*b));
1.30 niallo 66: /* Postpone creation of zero-sized buffers */
1.47 ray 67: if (len > 0)
68: b->cb_buf = xcalloc(1, len);
69: else
1.31 niallo 70: b->cb_buf = NULL;
1.1 jfb 71:
72: b->cb_size = len;
73: b->cb_len = 0;
74:
75: return (b);
76: }
77:
1.15 xsa 78: BUF *
1.68 tobias 79: cvs_buf_load(const char *path)
1.1 jfb 80: {
81: int fd;
1.54 joris 82: BUF *bp;
83:
84: if ((fd = open(path, O_RDONLY, 0600)) == -1)
1.63 joris 85: fatal("cvs_buf_load: failed to load '%s' : %s", path,
1.54 joris 86: strerror(errno));
87:
1.68 tobias 88: bp = cvs_buf_load_fd(fd);
1.54 joris 89: (void)close(fd);
90: return (bp);
91: }
92:
93: BUF *
1.68 tobias 94: cvs_buf_load_fd(int fd)
1.54 joris 95: {
1.1 jfb 96: struct stat st;
97: BUF *buf;
98:
1.54 joris 99: if (fstat(fd, &st) == -1)
100: fatal("cvs_buf_load_fd: fstat: %s", strerror(errno));
1.1 jfb 101:
1.54 joris 102: if (lseek(fd, 0, SEEK_SET) == -1)
103: fatal("cvs_buf_load_fd: lseek: %s", strerror(errno));
1.1 jfb 104:
1.68 tobias 105: buf = cvs_buf_alloc(st.st_size);
1.65 tobias 106: if (atomicio(read, fd, buf->cb_buf, buf->cb_size) != buf->cb_size)
107: fatal("cvs_buf_load_fd: read: %s", strerror(errno));
108: buf->cb_len = buf->cb_size;
1.1 jfb 109:
110: return (buf);
111: }
112:
113: /*
114: * cvs_buf_free()
115: *
116: * Free the buffer <b> and all associated data.
117: */
118: void
119: cvs_buf_free(BUF *b)
120: {
1.31 niallo 121: if (b->cb_buf != NULL)
122: xfree(b->cb_buf);
1.19 joris 123: xfree(b);
1.1 jfb 124: }
125:
126: /*
127: * cvs_buf_release()
128: *
129: * Free the buffer <b>'s structural information but do not free the contents
130: * of the buffer. Instead, they are returned and should be freed later using
131: * free().
132: */
1.58 otto 133: u_char *
1.1 jfb 134: cvs_buf_release(BUF *b)
135: {
1.8 jfb 136: u_char *tmp;
1.6 tedu 137:
1.1 jfb 138: tmp = b->cb_buf;
1.19 joris 139: xfree(b);
1.1 jfb 140: return (tmp);
141: }
142:
143: /*
144: * cvs_buf_empty()
145: *
146: * Empty the contents of the buffer <b> and reset pointers.
147: */
148: void
149: cvs_buf_empty(BUF *b)
150: {
1.16 moritz 151: memset(b->cb_buf, 0, b->cb_size);
1.1 jfb 152: b->cb_len = 0;
153: }
154:
155: /*
156: * cvs_buf_putc()
157: *
158: * Append a single character <c> to the end of the buffer <b>.
159: */
1.39 xsa 160: void
1.1 jfb 161: cvs_buf_putc(BUF *b, int c)
162: {
163: u_char *bp;
164:
1.57 ray 165: bp = b->cb_buf + b->cb_len;
1.1 jfb 166: if (bp == (b->cb_buf + b->cb_size)) {
167: /* extend */
1.68 tobias 168: cvs_buf_grow(b, (size_t)BUF_INCR);
1.1 jfb 169:
170: /* the buffer might have been moved */
1.57 ray 171: bp = b->cb_buf + b->cb_len;
1.1 jfb 172: }
173: *bp = (u_char)c;
174: b->cb_len++;
1.29 niallo 175: }
176:
177: /*
178: * cvs_buf_getc()
179: *
180: * Return u_char at buffer position <pos>.
181: *
182: */
183: u_char
1.40 ray 184: cvs_buf_getc(BUF *b, size_t pos)
1.29 niallo 185: {
1.57 ray 186: return (b->cb_buf[pos]);
1.1 jfb 187: }
188:
189: /*
190: * cvs_buf_append()
191: *
192: * Append <len> bytes of data pointed to by <data> to the buffer <b>. If the
193: * buffer is too small to accept all data, it will attempt to append as much
194: * data as possible, or if the BUF_AUTOEXT flag is set for the buffer, it
195: * will get resized to an appropriate size to accept all data.
1.27 joris 196: * Returns the number of bytes successfully appended to the buffer.
1.1 jfb 197: */
1.68 tobias 198: void
1.1 jfb 199: cvs_buf_append(BUF *b, const void *data, size_t len)
200: {
1.68 tobias 201: size_t left;
1.8 jfb 202: u_char *bp, *bep;
1.1 jfb 203:
1.57 ray 204: bp = b->cb_buf + b->cb_len;
1.1 jfb 205: bep = b->cb_buf + b->cb_size;
206: left = bep - bp;
207:
208: if (left < len) {
1.68 tobias 209: cvs_buf_grow(b, len - left);
210: bp = b->cb_buf + b->cb_len;
1.1 jfb 211: }
212:
1.68 tobias 213: memcpy(bp, data, len);
214: b->cb_len += len;
1.1 jfb 215: }
216:
217: /*
1.16 moritz 218: * cvs_buf_len()
1.1 jfb 219: *
220: * Returns the size of the buffer that is being used.
221: */
222: size_t
1.16 moritz 223: cvs_buf_len(BUF *b)
1.1 jfb 224: {
225: return (b->cb_len);
226: }
227:
228: /*
1.7 djm 229: * cvs_buf_write_fd()
1.1 jfb 230: *
1.7 djm 231: * Write the contents of the buffer <b> to the specified <fd>
1.1 jfb 232: */
233: int
1.7 djm 234: cvs_buf_write_fd(BUF *b, int fd)
1.1 jfb 235: {
1.65 tobias 236: if (atomicio(vwrite, fd, b->cb_buf, b->cb_len) != b->cb_len)
237: return (-1);
1.7 djm 238: return (0);
239: }
240:
241: /*
242: * cvs_buf_write()
243: *
244: * Write the contents of the buffer <b> to the file whose path is given in
245: * <path>. If the file does not exist, it is created with mode <mode>.
246: */
247: int
248: cvs_buf_write(BUF *b, const char *path, mode_t mode)
249: {
1.22 xsa 250: int fd;
1.32 niallo 251: open:
252: if ((fd = open(path, O_WRONLY|O_CREAT|O_TRUNC, mode)) == -1) {
1.49 deraadt 253: if (errno == EACCES && unlink(path) != -1)
1.32 niallo 254: goto open;
255: else
256: fatal("open: `%s': %s", path, strerror(errno));
257: }
1.7 djm 258:
1.22 xsa 259: if (cvs_buf_write_fd(b, fd) == -1) {
1.7 djm 260: (void)unlink(path);
1.22 xsa 261: fatal("cvs_buf_write: cvs_buf_write_fd: `%s'", path);
1.7 djm 262: }
1.44 niallo 263:
264: if (fchmod(fd, mode) < 0)
1.51 joris 265: cvs_log(LP_ERR, "permissions not set on file %s", path);
1.44 niallo 266:
1.1 jfb 267: (void)close(fd);
1.24 joris 268:
1.22 xsa 269: return (0);
1.1 jfb 270: }
271:
1.7 djm 272: /*
273: * cvs_buf_write_stmp()
274: *
1.13 joris 275: * Write the contents of the buffer <b> to a temporary file whose path is
1.7 djm 276: * specified using <template> (see mkstemp.3). NB. This function will modify
277: * <template>, as per mkstemp
278: */
1.69 ! joris 279: int
1.55 ray 280: cvs_buf_write_stmp(BUF *b, char *template, struct timeval *tv)
1.7 djm 281: {
1.22 xsa 282: int fd;
1.7 djm 283:
1.20 xsa 284: if ((fd = mkstemp(template)) == -1)
285: fatal("mkstemp: `%s': %s", template, strerror(errno));
1.7 djm 286:
1.22 xsa 287: if (cvs_buf_write_fd(b, fd) == -1) {
1.7 djm 288: (void)unlink(template);
1.22 xsa 289: fatal("cvs_buf_write_stmp: cvs_buf_write_fd: `%s'", template);
1.7 djm 290: }
1.44 niallo 291:
1.51 joris 292: if (tv != NULL) {
293: if (futimes(fd, tv) == -1)
294: fatal("cvs_buf_write_stmp: futimes failed");
295: }
296:
1.69 ! joris 297: cvs_worklist_add(template, &temp_files);
! 298:
! 299: if (lseek(fd, SEEK_SET, 0) < 0)
! 300: fatal("cvs_buf_write_stmp: lseek: %s", strerror(errno));
1.51 joris 301:
1.69 ! joris 302: return (fd);
1.7 djm 303: }
1.1 jfb 304:
305: /*
306: * cvs_buf_grow()
307: *
308: * Grow the buffer <b> by <len> bytes. The contents are unchanged by this
309: * operation regardless of the result.
310: */
1.46 ray 311: static void
1.1 jfb 312: cvs_buf_grow(BUF *b, size_t len)
313: {
1.61 ray 314: b->cb_buf = xrealloc(b->cb_buf, 1, b->cb_size + len);
1.1 jfb 315: b->cb_size += len;
316: }
1.43 xsa 317:
318: /*
319: * cvs_buf_copy()
320: *
321: * Copy the first <len> bytes of data in the buffer <b> starting at offset
322: * <off> in the destination buffer <dst>, which can accept up to <len> bytes.
323: * Returns the number of bytes successfully copied, or -1 on failure.
324: */
325: ssize_t
326: cvs_buf_copy(BUF *b, size_t off, void *dst, size_t len)
327: {
328: size_t rc;
329:
330: if (off > b->cb_len)
331: fatal("cvs_buf_copy failed");
332:
333: rc = MIN(len, (b->cb_len - off));
334: memcpy(dst, b->cb_buf + off, rc);
335:
336: return (ssize_t)rc;
337: }
338:
339: /*
340: * cvs_buf_peek()
341: *
342: * Peek at the contents of the buffer <b> at offset <off>.
343: */
1.58 otto 344: const u_char *
1.43 xsa 345: cvs_buf_peek(BUF *b, size_t off)
346: {
347: if (off >= b->cb_len)
348: return (NULL);
349:
350: return (b->cb_buf + off);
1.52 joris 351: }
352:
353: int
1.59 ray 354: cvs_buf_differ(const BUF *b1, const BUF *b2)
1.52 joris 355: {
1.59 ray 356: if (b1->cb_len != b2->cb_len)
1.52 joris 357: return (1);
358:
1.59 ray 359: return (memcmp(b1->cb_buf, b2->cb_buf, b1->cb_len));
1.43 xsa 360: }