teach diff machinery about --ignore-space-at-eol
[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) {
2344d47f 194 for (i1 = i2 = 0; i1 < s1 && i2 < s2; ) {
0d21efa5
JS
195 if (isspace(l1[i1]))
196 while (isspace(l1[i1]) && i1 < s1)
197 i1++;
2344d47f 198 if (isspace(l2[i2]))
0d21efa5
JS
199 while (isspace(l2[i2]) && i2 < s2)
200 i2++;
2344d47f
JS
201 if (i1 < s1 && i2 < s2 && l1[i1++] != l2[i2++])
202 return 0;
0d21efa5 203 }
2344d47f 204 return (i1 >= s1 && i2 >= s2);
0d21efa5 205 } else if (flags & XDF_IGNORE_WHITESPACE_CHANGE) {
2344d47f 206 for (i1 = i2 = 0; i1 < s1 && i2 < s2; ) {
0d21efa5
JS
207 if (isspace(l1[i1])) {
208 if (!isspace(l2[i2]))
2344d47f 209 return 0;
0d21efa5
JS
210 while (isspace(l1[i1]) && i1 < s1)
211 i1++;
212 while (isspace(l2[i2]) && i2 < s2)
213 i2++;
2344d47f
JS
214 } else if (l1[i1++] != l2[i2++])
215 return 0;
0d21efa5 216 }
2344d47f 217 return (i1 >= s1 && i2 >= s2);
859f9c45
JS
218 } else if (flags & XDF_IGNORE_WHITESPACE_AT_EOL) {
219 for (i1 = i2 = 0; i1 < s1 && i2 < s2; ) {
220 if (l1[i1] != l2[i2]) {
221 while (i1 < s1 && isspace(l1[i1]))
222 i1++;
223 while (i2 < s2 && isspace(l2[i2]))
224 i2++;
225 if (i1 < s1 || i2 < s2)
226 return 0;
227 return 1;
228 }
229 i1++;
230 i2++;
231 }
232 return i1 >= s1 && i2 >= s2;
0d21efa5
JS
233 } else
234 return s1 == s2 && !memcmp(l1, l2, s1);
235
236 return 0;
237}
3443546f 238
0d21efa5 239unsigned long xdl_hash_record(char const **data, char const *top, long flags) {
3443546f
LT
240 unsigned long ha = 5381;
241 char const *ptr = *data;
242
243 for (; ptr < top && *ptr != '\n'; ptr++) {
0d21efa5 244 if (isspace(*ptr) && (flags & XDF_WHITESPACE_FLAGS)) {
859f9c45 245 const char *ptr2 = ptr;
2344d47f
JS
246 while (ptr + 1 < top && isspace(ptr[1])
247 && ptr[1] != '\n')
0d21efa5 248 ptr++;
c7c24889
JS
249 if (flags & XDF_IGNORE_WHITESPACE_CHANGE
250 && ptr[1] != '\n') {
0d21efa5
JS
251 ha += (ha << 5);
252 ha ^= (unsigned long) ' ';
253 }
859f9c45
JS
254 if (flags & XDF_IGNORE_WHITESPACE_AT_EOL
255 && ptr[1] != '\n') {
256 while (ptr2 != ptr + 1) {
257 ha += (ha << 5);
258 ha ^= (unsigned long) *ptr2;
259 ptr2++;
260 }
261 }
0d21efa5
JS
262 continue;
263 }
3443546f
LT
264 ha += (ha << 5);
265 ha ^= (unsigned long) *ptr;
266 }
267 *data = ptr < top ? ptr + 1: ptr;
268
269 return ha;
270}
271
272
273unsigned int xdl_hashbits(unsigned int size) {
274 unsigned int val = 1, bits = 0;
275
276 for (; val < size && bits < CHAR_BIT * sizeof(unsigned int); val <<= 1, bits++);
277 return bits ? bits: 1;
278}
279
280
281int xdl_num_out(char *out, long val) {
282 char *ptr, *str = out;
283 char buf[32];
284
285 ptr = buf + sizeof(buf) - 1;
286 *ptr = '\0';
287 if (val < 0) {
288 *--ptr = '-';
289 val = -val;
290 }
291 for (; val && ptr > buf; val /= 10)
292 *--ptr = "0123456789"[val % 10];
293 if (*ptr)
294 for (; *ptr; ptr++, str++)
295 *str = *ptr;
296 else
297 *str++ = '0';
298 *str = '\0';
299
300 return str - out;
301}
302
303
304long xdl_atol(char const *str, char const **next) {
305 long val, base;
306 char const *top;
307
308 for (top = str; XDL_ISDIGIT(*top); top++);
309 if (next)
310 *next = top;
311 for (val = 0, base = 1, top--; top >= str; top--, base *= 10)
312 val += base * (long)(*top - '0');
313 return val;
314}
315
316
acb72577
MW
317int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
318 const char *func, long funclen, xdemitcb_t *ecb) {
3443546f
LT
319 int nb = 0;
320 mmbuffer_t mb;
321 char buf[128];
322
323 memcpy(buf, "@@ -", 4);
324 nb += 4;
325
ca557aff 326 nb += xdl_num_out(buf + nb, c1 ? s1: s1 - 1);
3443546f 327
3ce8f089
JH
328 if (c1 != 1) {
329 memcpy(buf + nb, ",", 1);
330 nb += 1;
3443546f 331
3ce8f089
JH
332 nb += xdl_num_out(buf + nb, c1);
333 }
3443546f
LT
334
335 memcpy(buf + nb, " +", 2);
336 nb += 2;
337
ca557aff 338 nb += xdl_num_out(buf + nb, c2 ? s2: s2 - 1);
3443546f 339
3ce8f089
JH
340 if (c2 != 1) {
341 memcpy(buf + nb, ",", 1);
342 nb += 1;
3443546f 343
3ce8f089
JH
344 nb += xdl_num_out(buf + nb, c2);
345 }
3443546f 346
acb72577
MW
347 memcpy(buf + nb, " @@", 3);
348 nb += 3;
349 if (func && funclen) {
350 buf[nb++] = ' ';
351 if (funclen > sizeof(buf) - nb - 1)
352 funclen = sizeof(buf) - nb - 1;
353 memcpy(buf + nb, func, funclen);
354 nb += funclen;
355 }
356 buf[nb++] = '\n';
3443546f
LT
357
358 mb.ptr = buf;
359 mb.size = nb;
360 if (ecb->outf(ecb->priv, &mb, 1) < 0)
361 return -1;
362
363 return 0;
364}
365