Teach diff about -b and -w flags
[git/git.git] / xdiff / xutils.c
CommitLineData
3443546f
LT
1/*
2 * LibXDiff by Davide Libenzi ( File Differential Library )
3 * Copyright (C) 2003 Davide Libenzi
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2.1 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * Davide Libenzi <davidel@xmailserver.org>
20 *
21 */
22
23#include "xinclude.h"
24
25
26
27#define XDL_GUESS_NLINES 256
28
29
30
31
ca557aff
DL
32long xdl_bogosqrt(long n) {
33 long i;
34
35 /*
36 * Classical integer square root approximation using shifts.
37 */
38 for (i = 1; n > 0; n >>= 2)
39 i <<= 1;
40
41 return i;
42}
43
44
3443546f
LT
45int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize,
46 xdemitcb_t *ecb) {
d281786f 47 int i = 2;
621c53cc 48 mmbuffer_t mb[3];
3443546f
LT
49
50 mb[0].ptr = (char *) pre;
51 mb[0].size = psize;
52 mb[1].ptr = (char *) rec;
53 mb[1].size = size;
d281786f
JH
54 if (size > 0 && rec[size - 1] != '\n') {
55 mb[2].ptr = (char *) "\n\\ No newline at end of file\n";
621c53cc 56 mb[2].size = strlen(mb[2].ptr);
d281786f 57 i++;
621c53cc 58 }
621c53cc 59 if (ecb->outf(ecb->priv, mb, i) < 0) {
3443546f
LT
60
61 return -1;
62 }
63
64 return 0;
65}
66
67void *xdl_mmfile_first(mmfile_t *mmf, long *size)
68{
69 *size = mmf->size;
70 return mmf->ptr;
71}
72
73
74void *xdl_mmfile_next(mmfile_t *mmf, long *size)
75{
76 return NULL;
77}
78
79
80long xdl_mmfile_size(mmfile_t *mmf)
81{
82 return mmf->size;
83}
84
85
86int xdl_cha_init(chastore_t *cha, long isize, long icount) {
87
88 cha->head = cha->tail = NULL;
89 cha->isize = isize;
90 cha->nsize = icount * isize;
91 cha->ancur = cha->sncur = NULL;
92 cha->scurr = 0;
93
94 return 0;
95}
96
97
98void xdl_cha_free(chastore_t *cha) {
99 chanode_t *cur, *tmp;
100
101 for (cur = cha->head; (tmp = cur) != NULL;) {
102 cur = cur->next;
103 xdl_free(tmp);
104 }
105}
106
107
108void *xdl_cha_alloc(chastore_t *cha) {
109 chanode_t *ancur;
110 void *data;
111
112 if (!(ancur = cha->ancur) || ancur->icurr == cha->nsize) {
113 if (!(ancur = (chanode_t *) xdl_malloc(sizeof(chanode_t) + cha->nsize))) {
114
115 return NULL;
116 }
117 ancur->icurr = 0;
118 ancur->next = NULL;
119 if (cha->tail)
120 cha->tail->next = ancur;
121 if (!cha->head)
122 cha->head = ancur;
123 cha->tail = ancur;
124 cha->ancur = ancur;
125 }
126
127 data = (char *) ancur + sizeof(chanode_t) + ancur->icurr;
128 ancur->icurr += cha->isize;
129
130 return data;
131}
132
133
134void *xdl_cha_first(chastore_t *cha) {
135 chanode_t *sncur;
136
137 if (!(cha->sncur = sncur = cha->head))
138 return NULL;
139
140 cha->scurr = 0;
141
142 return (char *) sncur + sizeof(chanode_t) + cha->scurr;
143}
144
145
146void *xdl_cha_next(chastore_t *cha) {
147 chanode_t *sncur;
148
149 if (!(sncur = cha->sncur))
150 return NULL;
151 cha->scurr += cha->isize;
152 if (cha->scurr == sncur->icurr) {
153 if (!(sncur = cha->sncur = sncur->next))
154 return NULL;
155 cha->scurr = 0;
156 }
157
158 return (char *) sncur + sizeof(chanode_t) + cha->scurr;
159}
160
161
162long xdl_guess_lines(mmfile_t *mf) {
163 long nl = 0, size, tsize = 0;
164 char const *data, *cur, *top;
165
166 if ((cur = data = xdl_mmfile_first(mf, &size)) != NULL) {
167 for (top = data + size; nl < XDL_GUESS_NLINES;) {
168 if (cur >= top) {
169 tsize += (long) (cur - data);
170 if (!(cur = data = xdl_mmfile_next(mf, &size)))
171 break;
172 top = data + size;
173 }
174 nl++;
175 if (!(cur = memchr(cur, '\n', top - cur)))
176 cur = top;
177 else
178 cur++;
179 }
180 tsize += (long) (cur - data);
181 }
182
183 if (nl && tsize)
184 nl = xdl_mmfile_size(mf) / (tsize / nl);
185
186 return nl + 1;
187}
188
0d21efa5
JS
189int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags)
190{
191 int i1, i2;
192
193 if (flags & XDF_IGNORE_WHITESPACE) {
194 for (i1 = i2 = 0; i1 < s1 && i2 < s2; i1++, i2++) {
195 if (isspace(l1[i1]))
196 while (isspace(l1[i1]) && i1 < s1)
197 i1++;
198 else if (isspace(l2[i2]))
199 while (isspace(l2[i2]) && i2 < s2)
200 i2++;
201 else if (l1[i1] != l2[i2])
202 return l2[i2] - l1[i1];
203 }
204 if (i1 >= s1)
205 return 1;
206 else if (i2 >= s2)
207 return -1;
208 } else if (flags & XDF_IGNORE_WHITESPACE_CHANGE) {
209 for (i1 = i2 = 0; i1 < s1 && i2 < s2; i1++, i2++) {
210 if (isspace(l1[i1])) {
211 if (!isspace(l2[i2]))
212 return -1;
213 while (isspace(l1[i1]) && i1 < s1)
214 i1++;
215 while (isspace(l2[i2]) && i2 < s2)
216 i2++;
217 } else if (l1[i1] != l2[i2])
218 return l2[i2] - l1[i1];
219 }
220 if (i1 >= s1)
221 return 1;
222 else if (i2 >= s2)
223 return -1;
224 } else
225 return s1 == s2 && !memcmp(l1, l2, s1);
226
227 return 0;
228}
3443546f 229
0d21efa5 230unsigned long xdl_hash_record(char const **data, char const *top, long flags) {
3443546f
LT
231 unsigned long ha = 5381;
232 char const *ptr = *data;
233
234 for (; ptr < top && *ptr != '\n'; ptr++) {
0d21efa5
JS
235 if (isspace(*ptr) && (flags & XDF_WHITESPACE_FLAGS)) {
236 while (ptr < top && isspace(*ptr) && ptr[1] != '\n')
237 ptr++;
238 if (flags & XDF_IGNORE_WHITESPACE_CHANGE) {
239 ha += (ha << 5);
240 ha ^= (unsigned long) ' ';
241 }
242 continue;
243 }
3443546f
LT
244 ha += (ha << 5);
245 ha ^= (unsigned long) *ptr;
246 }
247 *data = ptr < top ? ptr + 1: ptr;
248
249 return ha;
250}
251
252
253unsigned int xdl_hashbits(unsigned int size) {
254 unsigned int val = 1, bits = 0;
255
256 for (; val < size && bits < CHAR_BIT * sizeof(unsigned int); val <<= 1, bits++);
257 return bits ? bits: 1;
258}
259
260
261int xdl_num_out(char *out, long val) {
262 char *ptr, *str = out;
263 char buf[32];
264
265 ptr = buf + sizeof(buf) - 1;
266 *ptr = '\0';
267 if (val < 0) {
268 *--ptr = '-';
269 val = -val;
270 }
271 for (; val && ptr > buf; val /= 10)
272 *--ptr = "0123456789"[val % 10];
273 if (*ptr)
274 for (; *ptr; ptr++, str++)
275 *str = *ptr;
276 else
277 *str++ = '0';
278 *str = '\0';
279
280 return str - out;
281}
282
283
284long xdl_atol(char const *str, char const **next) {
285 long val, base;
286 char const *top;
287
288 for (top = str; XDL_ISDIGIT(*top); top++);
289 if (next)
290 *next = top;
291 for (val = 0, base = 1, top--; top >= str; top--, base *= 10)
292 val += base * (long)(*top - '0');
293 return val;
294}
295
296
acb72577
MW
297int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
298 const char *func, long funclen, xdemitcb_t *ecb) {
3443546f
LT
299 int nb = 0;
300 mmbuffer_t mb;
301 char buf[128];
302
303 memcpy(buf, "@@ -", 4);
304 nb += 4;
305
ca557aff 306 nb += xdl_num_out(buf + nb, c1 ? s1: s1 - 1);
3443546f 307
3ce8f089
JH
308 if (c1 != 1) {
309 memcpy(buf + nb, ",", 1);
310 nb += 1;
3443546f 311
3ce8f089
JH
312 nb += xdl_num_out(buf + nb, c1);
313 }
3443546f
LT
314
315 memcpy(buf + nb, " +", 2);
316 nb += 2;
317
ca557aff 318 nb += xdl_num_out(buf + nb, c2 ? s2: s2 - 1);
3443546f 319
3ce8f089
JH
320 if (c2 != 1) {
321 memcpy(buf + nb, ",", 1);
322 nb += 1;
3443546f 323
3ce8f089
JH
324 nb += xdl_num_out(buf + nb, c2);
325 }
3443546f 326
acb72577
MW
327 memcpy(buf + nb, " @@", 3);
328 nb += 3;
329 if (func && funclen) {
330 buf[nb++] = ' ';
331 if (funclen > sizeof(buf) - nb - 1)
332 funclen = sizeof(buf) - nb - 1;
333 memcpy(buf + nb, func, funclen);
334 nb += funclen;
335 }
336 buf[nb++] = '\n';
3443546f
LT
337
338 mb.ptr = buf;
339 mb.size = nb;
340 if (ecb->outf(ecb->priv, &mb, 1) < 0)
341 return -1;
342
343 return 0;
344}
345