]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * LibXDiff by Davide Libenzi ( File Differential Library ) | |
3 | * Copyright (C) 2003-2006 Davide Libenzi, Johannes E. Schindelin | |
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 | typedef struct s_xdmerge { | |
26 | struct s_xdmerge *next; | |
27 | /* | |
28 | * 0 = conflict, | |
29 | * 1 = no conflict, take first, | |
30 | * 2 = no conflict, take second. | |
31 | */ | |
32 | int mode; | |
33 | long i1, i2; | |
34 | long chg1, chg2; | |
35 | } xdmerge_t; | |
36 | ||
37 | static int xdl_append_merge(xdmerge_t **merge, int mode, | |
38 | long i1, long chg1, long i2, long chg2) | |
39 | { | |
40 | xdmerge_t *m = *merge; | |
41 | if (m && mode == m->mode && | |
42 | (i1 == m->i1 + m->chg1 || i2 == m->i2 + m->chg2)) { | |
43 | m->chg1 = i1 + chg1 - m->i1; | |
44 | m->chg2 = i2 + chg2 - m->i2; | |
45 | } else { | |
46 | m = xdl_malloc(sizeof(xdmerge_t)); | |
47 | if (!m) | |
48 | return -1; | |
49 | m->next = NULL; | |
50 | m->mode = mode; | |
51 | m->i1 = i1; | |
52 | m->chg1 = chg1; | |
53 | m->i2 = i2; | |
54 | m->chg2 = chg2; | |
55 | if (*merge) | |
56 | (*merge)->next = m; | |
57 | *merge = m; | |
58 | } | |
59 | return 0; | |
60 | } | |
61 | ||
62 | static int xdl_cleanup_merge(xdmerge_t *c) | |
63 | { | |
64 | int count = 0; | |
65 | xdmerge_t *next_c; | |
66 | ||
67 | /* were there conflicts? */ | |
68 | for (; c; c = next_c) { | |
69 | if (c->mode == 0) | |
70 | count++; | |
71 | next_c = c->next; | |
72 | free(c); | |
73 | } | |
74 | return count; | |
75 | } | |
76 | ||
77 | static int xdl_merge_cmp_lines(xdfenv_t *xe1, int i1, xdfenv_t *xe2, int i2, | |
78 | int line_count, long flags) | |
79 | { | |
80 | int i; | |
81 | xrecord_t **rec1 = xe1->xdf2.recs + i1; | |
82 | xrecord_t **rec2 = xe2->xdf2.recs + i2; | |
83 | ||
84 | for (i = 0; i < line_count; i++) { | |
85 | int result = xdl_recmatch(rec1[i]->ptr, rec1[i]->size, | |
86 | rec2[i]->ptr, rec2[i]->size, flags); | |
87 | if (!result) | |
88 | return -1; | |
89 | } | |
90 | return 0; | |
91 | } | |
92 | ||
93 | static int xdl_recs_copy(xdfenv_t *xe, int i, int count, int add_nl, char *dest) | |
94 | { | |
95 | xrecord_t **recs = xe->xdf2.recs + i; | |
96 | int size = 0; | |
97 | ||
98 | if (count < 1) | |
99 | return 0; | |
100 | ||
101 | for (i = 0; i < count; size += recs[i++]->size) | |
102 | if (dest) | |
103 | memcpy(dest + size, recs[i]->ptr, recs[i]->size); | |
104 | if (add_nl) { | |
105 | i = recs[count - 1]->size; | |
106 | if (i == 0 || recs[count - 1]->ptr[i - 1] != '\n') { | |
107 | if (dest) | |
108 | dest[size] = '\n'; | |
109 | size++; | |
110 | } | |
111 | } | |
112 | return size; | |
113 | } | |
114 | ||
115 | static int xdl_fill_merge_buffer(xdfenv_t *xe1, const char *name1, | |
116 | xdfenv_t *xe2, const char *name2, xdmerge_t *m, char *dest) | |
117 | { | |
118 | const int marker_size = 7; | |
119 | int marker1_size = (name1 ? strlen(name1) + 1 : 0); | |
120 | int marker2_size = (name2 ? strlen(name2) + 1 : 0); | |
121 | int conflict_marker_size = 3 * (marker_size + 1) | |
122 | + marker1_size + marker2_size; | |
123 | int size, i1, j; | |
124 | ||
125 | for (size = i1 = 0; m; m = m->next) { | |
126 | if (m->mode == 0) { | |
127 | size += xdl_recs_copy(xe1, i1, m->i1 - i1, 0, | |
128 | dest ? dest + size : NULL); | |
129 | if (dest) { | |
130 | for (j = 0; j < marker_size; j++) | |
131 | dest[size++] = '<'; | |
132 | if (marker1_size) { | |
133 | dest[size] = ' '; | |
134 | memcpy(dest + size + 1, name1, | |
135 | marker1_size - 1); | |
136 | size += marker1_size; | |
137 | } | |
138 | dest[size++] = '\n'; | |
139 | } else | |
140 | size += conflict_marker_size; | |
141 | size += xdl_recs_copy(xe1, m->i1, m->chg1, 1, | |
142 | dest ? dest + size : NULL); | |
143 | if (dest) { | |
144 | for (j = 0; j < marker_size; j++) | |
145 | dest[size++] = '='; | |
146 | dest[size++] = '\n'; | |
147 | } | |
148 | size += xdl_recs_copy(xe2, m->i2, m->chg2, 1, | |
149 | dest ? dest + size : NULL); | |
150 | if (dest) { | |
151 | for (j = 0; j < marker_size; j++) | |
152 | dest[size++] = '>'; | |
153 | if (marker2_size) { | |
154 | dest[size] = ' '; | |
155 | memcpy(dest + size + 1, name2, | |
156 | marker2_size - 1); | |
157 | size += marker2_size; | |
158 | } | |
159 | dest[size++] = '\n'; | |
160 | } | |
161 | } else if (m->mode == 1) | |
162 | size += xdl_recs_copy(xe1, i1, m->i1 + m->chg1 - i1, 0, | |
163 | dest ? dest + size : NULL); | |
164 | else if (m->mode == 2) | |
165 | size += xdl_recs_copy(xe2, m->i2 - m->i1 + i1, | |
166 | m->i1 + m->chg2 - i1, 0, | |
167 | dest ? dest + size : NULL); | |
168 | i1 = m->i1 + m->chg1; | |
169 | } | |
170 | size += xdl_recs_copy(xe1, i1, xe1->xdf2.nrec - i1, 0, | |
171 | dest ? dest + size : NULL); | |
172 | return size; | |
173 | } | |
174 | ||
175 | /* | |
176 | * Sometimes, changes are not quite identical, but differ in only a few | |
177 | * lines. Try hard to show only these few lines as conflicting. | |
178 | */ | |
179 | static int xdl_refine_conflicts(xdfenv_t *xe1, xdfenv_t *xe2, xdmerge_t *m, | |
180 | xpparam_t const *xpp) | |
181 | { | |
182 | for (; m; m = m->next) { | |
183 | mmfile_t t1, t2; | |
184 | xdfenv_t xe; | |
185 | xdchange_t *xscr, *x; | |
186 | int i1 = m->i1, i2 = m->i2; | |
187 | ||
188 | /* let's handle just the conflicts */ | |
189 | if (m->mode) | |
190 | continue; | |
191 | ||
192 | /* | |
193 | * This probably does not work outside git, since | |
194 | * we have a very simple mmfile structure. | |
195 | */ | |
196 | t1.ptr = (char *)xe1->xdf2.recs[m->i1]->ptr; | |
197 | t1.size = xe1->xdf2.recs[m->i1 + m->chg1 - 1]->ptr | |
198 | + xe1->xdf2.recs[m->i1 + m->chg1 - 1]->size - t1.ptr; | |
199 | t2.ptr = (char *)xe2->xdf2.recs[m->i2]->ptr; | |
200 | t2.size = xe2->xdf2.recs[m->i2 + m->chg2 - 1]->ptr | |
201 | + xe2->xdf2.recs[m->i2 + m->chg2 - 1]->size - t2.ptr; | |
202 | if (xdl_do_diff(&t1, &t2, xpp, &xe) < 0) | |
203 | return -1; | |
204 | if (xdl_change_compact(&xe.xdf1, &xe.xdf2, xpp->flags) < 0 || | |
205 | xdl_change_compact(&xe.xdf2, &xe.xdf1, xpp->flags) < 0 || | |
206 | xdl_build_script(&xe, &xscr) < 0) { | |
207 | xdl_free_env(&xe); | |
208 | return -1; | |
209 | } | |
210 | if (!xscr) { | |
211 | /* If this happens, it's a bug. */ | |
212 | xdl_free_env(&xe); | |
213 | return -2; | |
214 | } | |
215 | x = xscr; | |
216 | m->i1 = xscr->i1 + i1; | |
217 | m->chg1 = xscr->chg1; | |
218 | m->i2 = xscr->i2 + i2; | |
219 | m->chg2 = xscr->chg2; | |
220 | while (xscr->next) { | |
221 | xdmerge_t *m2 = xdl_malloc(sizeof(xdmerge_t)); | |
222 | if (!m2) { | |
223 | xdl_free_env(&xe); | |
224 | xdl_free_script(x); | |
225 | return -1; | |
226 | } | |
227 | xscr = xscr->next; | |
228 | m2->next = m->next; | |
229 | m->next = m2; | |
230 | m = m2; | |
231 | m->mode = 0; | |
232 | m->i1 = xscr->i1 + i1; | |
233 | m->chg1 = xscr->chg1; | |
234 | m->i2 = xscr->i2 + i2; | |
235 | m->chg2 = xscr->chg2; | |
236 | } | |
237 | xdl_free_env(&xe); | |
238 | xdl_free_script(x); | |
239 | } | |
240 | return 0; | |
241 | } | |
242 | ||
243 | /* | |
244 | * level == 0: mark all overlapping changes as conflict | |
245 | * level == 1: mark overlapping changes as conflict only if not identical | |
246 | * level == 2: analyze non-identical changes for minimal conflict set | |
247 | * | |
248 | * returns < 0 on error, == 0 for no conflicts, else number of conflicts | |
249 | */ | |
250 | static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1, const char *name1, | |
251 | xdfenv_t *xe2, xdchange_t *xscr2, const char *name2, | |
252 | int level, xpparam_t const *xpp, mmbuffer_t *result) { | |
253 | xdmerge_t *changes, *c; | |
254 | int i1, i2, chg1, chg2; | |
255 | ||
256 | c = changes = NULL; | |
257 | ||
258 | while (xscr1 && xscr2) { | |
259 | if (!changes) | |
260 | changes = c; | |
261 | if (xscr1->i1 + xscr1->chg1 < xscr2->i1) { | |
262 | i1 = xscr1->i2; | |
263 | i2 = xscr2->i2 - xscr2->i1 + xscr1->i1; | |
264 | chg1 = xscr1->chg2; | |
265 | chg2 = xscr1->chg1; | |
266 | if (xdl_append_merge(&c, 1, i1, chg1, i2, chg2)) { | |
267 | xdl_cleanup_merge(changes); | |
268 | return -1; | |
269 | } | |
270 | xscr1 = xscr1->next; | |
271 | continue; | |
272 | } | |
273 | if (xscr2->i1 + xscr2->chg1 < xscr1->i1) { | |
274 | i1 = xscr1->i2 - xscr1->i1 + xscr2->i1; | |
275 | i2 = xscr2->i2; | |
276 | chg1 = xscr2->chg1; | |
277 | chg2 = xscr2->chg2; | |
278 | if (xdl_append_merge(&c, 2, i1, chg1, i2, chg2)) { | |
279 | xdl_cleanup_merge(changes); | |
280 | return -1; | |
281 | } | |
282 | xscr2 = xscr2->next; | |
283 | continue; | |
284 | } | |
285 | if (level < 1 || xscr1->i1 != xscr2->i1 || | |
286 | xscr1->chg1 != xscr2->chg1 || | |
287 | xscr1->chg2 != xscr2->chg2 || | |
288 | xdl_merge_cmp_lines(xe1, xscr1->i2, | |
289 | xe2, xscr2->i2, | |
290 | xscr1->chg2, xpp->flags)) { | |
291 | /* conflict */ | |
292 | int off = xscr1->i1 - xscr2->i1; | |
293 | int ffo = off + xscr1->chg1 - xscr2->chg1; | |
294 | ||
295 | i1 = xscr1->i2; | |
296 | i2 = xscr2->i2; | |
297 | if (off > 0) | |
298 | i1 -= off; | |
299 | else | |
300 | i2 += off; | |
301 | chg1 = xscr1->i2 + xscr1->chg2 - i1; | |
302 | chg2 = xscr2->i2 + xscr2->chg2 - i2; | |
303 | if (ffo > 0) | |
304 | chg2 += ffo; | |
305 | else | |
306 | chg1 -= ffo; | |
307 | if (xdl_append_merge(&c, 0, i1, chg1, i2, chg2)) { | |
308 | xdl_cleanup_merge(changes); | |
309 | return -1; | |
310 | } | |
311 | } | |
312 | ||
313 | i1 = xscr1->i1 + xscr1->chg1; | |
314 | i2 = xscr2->i1 + xscr2->chg1; | |
315 | ||
316 | if (i1 > i2) { | |
317 | xscr1->chg1 -= i1 - i2; | |
318 | xscr1->i1 = i2; | |
319 | xscr1->i2 += xscr1->chg2; | |
320 | xscr1->chg2 = 0; | |
321 | xscr1 = xscr1->next; | |
322 | } else if (i2 > i1) { | |
323 | xscr2->chg1 -= i2 - i1; | |
324 | xscr2->i1 = i1; | |
325 | xscr2->i2 += xscr2->chg2; | |
326 | xscr2->chg2 = 0; | |
327 | xscr2 = xscr2->next; | |
328 | } else { | |
329 | xscr1 = xscr1->next; | |
330 | xscr2 = xscr2->next; | |
331 | } | |
332 | } | |
333 | while (xscr1) { | |
334 | if (!changes) | |
335 | changes = c; | |
336 | i1 = xscr1->i2; | |
337 | i2 = xscr1->i1 + xe2->xdf2.nrec - xe2->xdf1.nrec; | |
338 | chg1 = xscr1->chg2; | |
339 | chg2 = xscr1->chg1; | |
340 | if (xdl_append_merge(&c, 1, i1, chg1, i2, chg2)) { | |
341 | xdl_cleanup_merge(changes); | |
342 | return -1; | |
343 | } | |
344 | xscr1 = xscr1->next; | |
345 | } | |
346 | while (xscr2) { | |
347 | if (!changes) | |
348 | changes = c; | |
349 | i1 = xscr2->i1 + xe1->xdf2.nrec - xe1->xdf1.nrec; | |
350 | i2 = xscr2->i2; | |
351 | chg1 = xscr2->chg1; | |
352 | chg2 = xscr2->chg2; | |
353 | if (xdl_append_merge(&c, 2, i1, chg1, i2, chg2)) { | |
354 | xdl_cleanup_merge(changes); | |
355 | return -1; | |
356 | } | |
357 | xscr2 = xscr2->next; | |
358 | } | |
359 | if (!changes) | |
360 | changes = c; | |
361 | /* refine conflicts */ | |
362 | if (level > 1 && xdl_refine_conflicts(xe1, xe2, changes, xpp) < 0) { | |
363 | xdl_cleanup_merge(changes); | |
364 | return -1; | |
365 | } | |
366 | /* output */ | |
367 | if (result) { | |
368 | int size = xdl_fill_merge_buffer(xe1, name1, xe2, name2, | |
369 | changes, NULL); | |
370 | result->ptr = xdl_malloc(size); | |
371 | if (!result->ptr) { | |
372 | xdl_cleanup_merge(changes); | |
373 | return -1; | |
374 | } | |
375 | result->size = size; | |
376 | xdl_fill_merge_buffer(xe1, name1, xe2, name2, changes, | |
377 | result->ptr); | |
378 | } | |
379 | return xdl_cleanup_merge(changes); | |
380 | } | |
381 | ||
382 | int xdl_merge(mmfile_t *orig, mmfile_t *mf1, const char *name1, | |
383 | mmfile_t *mf2, const char *name2, | |
384 | xpparam_t const *xpp, int level, mmbuffer_t *result) { | |
385 | xdchange_t *xscr1, *xscr2; | |
386 | xdfenv_t xe1, xe2; | |
387 | int status; | |
388 | ||
389 | result->ptr = NULL; | |
390 | result->size = 0; | |
391 | ||
392 | if (xdl_do_diff(orig, mf1, xpp, &xe1) < 0 || | |
393 | xdl_do_diff(orig, mf2, xpp, &xe2) < 0) { | |
394 | return -1; | |
395 | } | |
396 | if (xdl_change_compact(&xe1.xdf1, &xe1.xdf2, xpp->flags) < 0 || | |
397 | xdl_change_compact(&xe1.xdf2, &xe1.xdf1, xpp->flags) < 0 || | |
398 | xdl_build_script(&xe1, &xscr1) < 0) { | |
399 | xdl_free_env(&xe1); | |
400 | return -1; | |
401 | } | |
402 | if (xdl_change_compact(&xe2.xdf1, &xe2.xdf2, xpp->flags) < 0 || | |
403 | xdl_change_compact(&xe2.xdf2, &xe2.xdf1, xpp->flags) < 0 || | |
404 | xdl_build_script(&xe2, &xscr2) < 0) { | |
405 | xdl_free_env(&xe2); | |
406 | return -1; | |
407 | } | |
408 | status = 0; | |
409 | if (xscr1 || xscr2) { | |
410 | if (!xscr1) { | |
411 | result->ptr = xdl_malloc(mf2->size); | |
412 | memcpy(result->ptr, mf2->ptr, mf2->size); | |
413 | result->size = mf2->size; | |
414 | } else if (!xscr2) { | |
415 | result->ptr = xdl_malloc(mf1->size); | |
416 | memcpy(result->ptr, mf1->ptr, mf1->size); | |
417 | result->size = mf1->size; | |
418 | } else { | |
419 | status = xdl_do_merge(&xe1, xscr1, name1, | |
420 | &xe2, xscr2, name2, | |
421 | level, xpp, result); | |
422 | } | |
423 | xdl_free_script(xscr1); | |
424 | xdl_free_script(xscr2); | |
425 | } | |
426 | xdl_free_env(&xe1); | |
427 | xdl_free_env(&xe2); | |
428 | ||
429 | return status; | |
430 | } |