rcsnum.c revision 1.12 
1/*	$OpenBSD: rcsnum.c,v 1.12 2005/05/31 08:58:48 xsa Exp $	*/
2/*
3 * Copyright (c) 2004 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/param.h>
28
29#include <ctype.h>
30#include <stdio.h>
31#include <stdlib.h>
32#include <string.h>
33
34#include "log.h"
35#include "rcs.h"
36
37
38static int rcsnum_setsize  (RCSNUM *, u_int);
39
40
41/*
42 * rcsnum_alloc()
43 *
44 * Allocate an RCS number structure and return a pointer to it on success,
45 * or NULL on failure.
46 */
47RCSNUM*
48rcsnum_alloc(void)
49{
50	RCSNUM *rnp;
51
52	rnp = (RCSNUM *)malloc(sizeof(*rnp));
53	if (rnp == NULL) {
54		rcs_errno = RCS_ERR_ERRNO;
55		return (NULL);
56	}
57	rnp->rn_len = 0;
58	rnp->rn_id = NULL;
59
60	return (rnp);
61}
62
63/*
64 * rcsnum_parse()
65 *
66 * Parse a string specifying an RCS number and return the corresponding RCSNUM.
67 */
68RCSNUM*
69rcsnum_parse(const char *str)
70{
71	char *ep;
72	RCSNUM *num;
73
74	if ((num = rcsnum_alloc()) == NULL)
75		return (NULL);
76
77	if ((rcsnum_aton(str, &ep, num) < 0) || (*ep != '\0')) {
78		rcsnum_free(num);
79		num = NULL;
80		if (*ep != '\0')
81			rcs_errno = RCS_ERR_BADNUM;
82	}
83
84	return (num);
85}
86
87/*
88 * rcsnum_free()
89 *
90 * Free an RCSNUM structure previously allocated with rcsnum_alloc().
91 */
92void
93rcsnum_free(RCSNUM *rn)
94{
95	if (rn->rn_id != NULL)
96		free(rn->rn_id);
97	free(rn);
98}
99
100/*
101 * rcsnum_tostr()
102 *
103 * Format the RCS number <nump> into a human-readable dot-separated
104 * representation and store the resulting string in <buf>, which is of size
105 * <blen>.
106 * Returns a pointer to the start of <buf> on success, or NULL on failure.
107 */
108char*
109rcsnum_tostr(const RCSNUM *nump, char *buf, size_t blen)
110{
111	u_int i;
112	char tmp[8];
113
114	if ((nump == NULL) || (nump->rn_len == 0)) {
115		buf[0] = '\0';
116		return (buf);
117	}
118
119	snprintf(buf, blen, "%u", nump->rn_id[0]);
120	for (i = 1; i < nump->rn_len; i++) {
121		snprintf(tmp, sizeof(tmp), ".%u", nump->rn_id[i]);
122		strlcat(buf, tmp, blen);
123	}
124
125	return (buf);
126}
127
128/*
129 * rcsnum_cpy()
130 *
131 * Copy the number stored in <nsrc> in the destination <ndst> up to <depth>
132 * numbers deep.
133 * Returns 0 on success, or -1 on failure.
134 */
135int
136rcsnum_cpy(const RCSNUM *nsrc, RCSNUM *ndst, u_int depth)
137{
138	u_int len;
139	size_t sz;
140	void *tmp;
141
142	len = nsrc->rn_len;
143	if ((depth != 0) && (len > depth))
144		len = depth;
145	sz = len * sizeof(u_int16_t);
146
147	tmp = realloc(ndst->rn_id, sz);
148	if (tmp == NULL) {
149		rcs_errno = RCS_ERR_ERRNO;
150		return (-1);
151	}
152
153	ndst->rn_id = (u_int16_t *)tmp;
154	ndst->rn_len = len;
155	memcpy(ndst->rn_id, nsrc->rn_id, sz);
156	return (0);
157}
158
159/*
160 * rcsnum_cmp()
161 *
162 * Compare the two numbers <n1> and <n2>. Returns -1 if <n1> is larger than
163 * <n2>, 0 if they are both the same, and 1 if <n2> is larger than <n1>.
164 * The <depth> argument specifies how many numbers deep should be checked for
165 * the result.  A value of 0 means that the depth will be the minimum of the
166 * two numbers.
167 */
168int
169rcsnum_cmp(const RCSNUM *n1, const RCSNUM *n2, u_int depth)
170{
171	int res;
172	u_int i;
173	size_t slen;
174
175	slen = MIN(n1->rn_len, n2->rn_len);
176	if ((depth != 0) && (slen > depth))
177		slen = depth;
178
179	for (i = 0; i < slen; i++) {
180		res = n1->rn_id[i] - n2->rn_id[i];
181		if (res < 0)
182			return (1);
183		else if (res > 0)
184			return (-1);
185	}
186
187	if (n1->rn_len > n2->rn_len)
188		return (-1);
189	else if (n2->rn_len > n1->rn_len)
190		return (1);
191
192	return (0);
193}
194
195/*
196 * rcsnum_aton()
197 *
198 * Translate the string <str> containing a sequence of digits and periods into
199 * its binary representation, which is stored in <nump>.  The address of the
200 * first byte not part of the number is stored in <ep> on return, if it is not
201 * NULL.
202 * Returns 0 on success, or -1 on failure.
203 */
204int
205rcsnum_aton(const char *str, char **ep, RCSNUM *nump)
206{
207	u_int32_t val;
208	const char *sp;
209	void *tmp;
210
211	if (nump->rn_id == NULL) {
212		nump->rn_id = (u_int16_t *)malloc(sizeof(u_int16_t));
213		if (nump->rn_id == NULL) {
214			rcs_errno = RCS_ERR_ERRNO;
215			return (-1);
216		}
217	}
218
219	nump->rn_len = 0;
220	nump->rn_id[0] = 0;
221
222	for (sp = str;; sp++) {
223		if (!isdigit(*sp) && (*sp != '.'))
224			break;
225
226		if (*sp == '.') {
227			if (nump->rn_len >= RCSNUM_MAXLEN - 1) {
228				rcs_errno = RCS_ERR_BADNUM;
229				goto rcsnum_aton_failed;
230			}
231
232			nump->rn_len++;
233			tmp = realloc(nump->rn_id,
234			    (nump->rn_len + 1) * sizeof(u_int16_t));
235			if (tmp == NULL)
236				goto rcsnum_aton_failed;
237			nump->rn_id = (u_int16_t *)tmp;
238			nump->rn_id[nump->rn_len] = 0;
239			continue;
240		}
241
242		val = (nump->rn_id[nump->rn_len] * 10) + (*sp - 0x30);
243		if (val > RCSNUM_MAXNUM) {
244			cvs_log(LP_ERR, "RCSNUM overflow");
245			goto rcsnum_aton_failed;
246		}
247
248		nump->rn_id[nump->rn_len] = val;
249	}
250
251	if (ep != NULL)
252		*(const char **)ep = sp;
253
254	nump->rn_len++;
255	return (nump->rn_len);
256
257rcsnum_aton_failed:
258	nump->rn_len = 0;
259	free(nump->rn_id);
260	nump->rn_id = NULL;
261	return (-1);
262}
263
264/*
265 * rcsnum_inc()
266 *
267 * Increment the revision number specified in <num>.
268 * Returns a pointer to the <num> on success, or NULL on failure.
269 */
270RCSNUM*
271rcsnum_inc(RCSNUM *num)
272{
273	if (num->rn_id[num->rn_len - 1] == RCSNUM_MAXNUM)
274		return (NULL);
275	num->rn_id[num->rn_len - 1]++;
276	return (num);
277}
278
279/*
280 * rcsnum_revtobr()
281 *
282 * Retrieve the branch number associated with the revision number <num>.
283 * If <num> is a branch revision, the returned value will be the same
284 * number as the argument.
285 */
286RCSNUM*
287rcsnum_revtobr(const RCSNUM *num)
288{
289	RCSNUM *brnum;
290
291	if (num->rn_len < 2)
292		return (NULL);
293
294	if ((brnum = rcsnum_alloc()) == NULL)
295		return (NULL);
296
297	rcsnum_cpy(num, brnum, 0);
298
299	if (!RCSNUM_ISBRANCH(brnum))
300		brnum->rn_len--;
301
302	return (brnum);
303}
304
305/*
306 * rcsnum_brtorev()
307 *
308 * Retrieve the initial revision number associated with the branch number <num>.
309 * If <num> is a revision number, an error will be returned.
310 */
311RCSNUM*
312rcsnum_brtorev(const RCSNUM *brnum)
313{
314	RCSNUM *num;
315
316	if (!RCSNUM_ISBRANCH(brnum)) {
317		return (NULL);
318	}
319
320	if ((num = rcsnum_alloc()) == NULL)
321		return (NULL);
322
323	if (rcsnum_setsize(num, brnum->rn_len + 1) < 0) {
324		rcsnum_free(num);
325		return (NULL);
326	}
327
328	rcsnum_cpy(brnum, num, brnum->rn_len);
329	num->rn_id[num->rn_len++] = 1;
330
331	return (num);
332}
333
334static int
335rcsnum_setsize(RCSNUM *num, u_int len)
336{
337	void *tmp;
338
339	tmp = realloc(num->rn_id, len * sizeof(u_int16_t));
340	if (tmp == NULL) {
341		rcs_errno = RCS_ERR_ERRNO;
342		return (-1);
343	}
344
345	num->rn_id = (u_int16_t *)tmp;
346	num->rn_len = len;
347	return (0);
348}
349