b99a57825f8510907f88575354cccf25eafd0052
1#include "cache.h"
2#include "config.h"
3#include "object-store.h"
4#include "xdiff-interface.h"
5#include "xdiff/xtypes.h"
6#include "xdiff/xdiffi.h"
7#include "xdiff/xemit.h"
8#include "xdiff/xmacros.h"
9#include "xdiff/xutils.h"
10
11struct xdiff_emit_state {
12 xdiff_emit_hunk_fn hunk_fn;
13 xdiff_emit_line_fn line_fn;
14 void *consume_callback_data;
15 struct strbuf remainder;
16};
17
18static int parse_num(char **cp_p, int *num_p)
19{
20 char *cp = *cp_p;
21 int num = 0;
22
23 while ('0' <= *cp && *cp <= '9')
24 num = num * 10 + *cp++ - '0';
25 if (!(cp - *cp_p))
26 return -1;
27 *cp_p = cp;
28 *num_p = num;
29 return 0;
30}
31
32int parse_hunk_header(char *line, int len,
33 int *ob, int *on,
34 int *nb, int *nn)
35{
36 char *cp;
37 cp = line + 4;
38 if (parse_num(&cp, ob)) {
39 bad_line:
40 return error("malformed diff output: %s", line);
41 }
42 if (*cp == ',') {
43 cp++;
44 if (parse_num(&cp, on))
45 goto bad_line;
46 }
47 else
48 *on = 1;
49 if (*cp++ != ' ' || *cp++ != '+')
50 goto bad_line;
51 if (parse_num(&cp, nb))
52 goto bad_line;
53 if (*cp == ',') {
54 cp++;
55 if (parse_num(&cp, nn))
56 goto bad_line;
57 }
58 else
59 *nn = 1;
60 return -!!memcmp(cp, " @@", 3);
61}
62
63static int xdiff_out_hunk(void *priv_,
64 long old_begin, long old_nr,
65 long new_begin, long new_nr,
66 const char *func, long funclen)
67{
68 struct xdiff_emit_state *priv = priv_;
69
70 if (priv->remainder.len)
71 BUG("xdiff emitted hunk in the middle of a line");
72
73 priv->hunk_fn(priv->consume_callback_data,
74 old_begin, old_nr, new_begin, new_nr,
75 func, funclen);
76 return 0;
77}
78
79static void consume_one(void *priv_, char *s, unsigned long size)
80{
81 struct xdiff_emit_state *priv = priv_;
82 char *ep;
83 while (size) {
84 unsigned long this_size;
85 ep = memchr(s, '\n', size);
86 this_size = (ep == NULL) ? size : (ep - s + 1);
87 priv->line_fn(priv->consume_callback_data, s, this_size);
88 size -= this_size;
89 s += this_size;
90 }
91}
92
93static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
94{
95 struct xdiff_emit_state *priv = priv_;
96 int i;
97
98 for (i = 0; i < nbuf; i++) {
99 if (mb[i].ptr[mb[i].size-1] != '\n') {
100 /* Incomplete line */
101 strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
102 continue;
103 }
104
105 /* we have a complete line */
106 if (!priv->remainder.len) {
107 consume_one(priv, mb[i].ptr, mb[i].size);
108 continue;
109 }
110 strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
111 consume_one(priv, priv->remainder.buf, priv->remainder.len);
112 strbuf_reset(&priv->remainder);
113 }
114 if (priv->remainder.len) {
115 consume_one(priv, priv->remainder.buf, priv->remainder.len);
116 strbuf_reset(&priv->remainder);
117 }
118 return 0;
119}
120
121/*
122 * Trim down common substring at the end of the buffers,
123 * but end on a complete line.
124 */
125static void trim_common_tail(mmfile_t *a, mmfile_t *b)
126{
127 const int blk = 1024;
128 long trimmed = 0, recovered = 0;
129 char *ap = a->ptr + a->size;
130 char *bp = b->ptr + b->size;
131 long smaller = (a->size < b->size) ? a->size : b->size;
132
133 while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {
134 trimmed += blk;
135 ap -= blk;
136 bp -= blk;
137 }
138
139 while (recovered < trimmed)
140 if (ap[recovered++] == '\n')
141 break;
142 a->size -= trimmed - recovered;
143 b->size -= trimmed - recovered;
144}
145
146int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb)
147{
148 mmfile_t a = *mf1;
149 mmfile_t b = *mf2;
150
151 if (mf1->size > MAX_XDIFF_SIZE || mf2->size > MAX_XDIFF_SIZE)
152 return -1;
153
154 if (!xecfg->ctxlen && !(xecfg->flags & XDL_EMIT_FUNCCONTEXT))
155 trim_common_tail(&a, &b);
156
157 return xdl_diff(&a, &b, xpp, xecfg, xecb);
158}
159
160void discard_hunk_line(void *priv,
161 long ob, long on, long nb, long nn,
162 const char *func, long funclen)
163{
164}
165
166int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
167 xdiff_emit_hunk_fn hunk_fn,
168 xdiff_emit_line_fn line_fn,
169 void *consume_callback_data,
170 xpparam_t const *xpp, xdemitconf_t const *xecfg)
171{
172 int ret;
173 struct xdiff_emit_state state;
174 xdemitcb_t ecb;
175
176 memset(&state, 0, sizeof(state));
177 state.hunk_fn = hunk_fn;
178 state.line_fn = line_fn;
179 state.consume_callback_data = consume_callback_data;
180 memset(&ecb, 0, sizeof(ecb));
181 if (hunk_fn)
182 ecb.out_hunk = xdiff_out_hunk;
183 ecb.out_line = xdiff_outf;
184 ecb.priv = &state;
185 strbuf_init(&state.remainder, 0);
186 ret = xdi_diff(mf1, mf2, xpp, xecfg, &ecb);
187 strbuf_release(&state.remainder);
188 return ret;
189}
190
191int read_mmfile(mmfile_t *ptr, const char *filename)
192{
193 struct stat st;
194 FILE *f;
195 size_t sz;
196
197 if (stat(filename, &st))
198 return error_errno("Could not stat %s", filename);
199 if ((f = fopen(filename, "rb")) == NULL)
200 return error_errno("Could not open %s", filename);
201 sz = xsize_t(st.st_size);
202 ptr->ptr = xmalloc(sz ? sz : 1);
203 if (sz && fread(ptr->ptr, sz, 1, f) != 1) {
204 fclose(f);
205 return error("Could not read %s", filename);
206 }
207 fclose(f);
208 ptr->size = sz;
209 return 0;
210}
211
212void read_mmblob(mmfile_t *ptr, const struct object_id *oid)
213{
214 unsigned long size;
215 enum object_type type;
216
217 if (!oidcmp(oid, &null_oid)) {
218 ptr->ptr = xstrdup("");
219 ptr->size = 0;
220 return;
221 }
222
223 ptr->ptr = read_object_file(oid, &type, &size);
224 if (!ptr->ptr || type != OBJ_BLOB)
225 die("unable to read blob object %s", oid_to_hex(oid));
226 ptr->size = size;
227}
228
229#define FIRST_FEW_BYTES 8000
230int buffer_is_binary(const char *ptr, unsigned long size)
231{
232 if (FIRST_FEW_BYTES < size)
233 size = FIRST_FEW_BYTES;
234 return !!memchr(ptr, 0, size);
235}
236
237struct ff_regs {
238 int nr;
239 struct ff_reg {
240 regex_t re;
241 int negate;
242 } *array;
243};
244
245static long ff_regexp(const char *line, long len,
246 char *buffer, long buffer_size, void *priv)
247{
248 struct ff_regs *regs = priv;
249 regmatch_t pmatch[2];
250 int i;
251 int result;
252
253 /* Exclude terminating newline (and cr) from matching */
254 if (len > 0 && line[len-1] == '\n') {
255 if (len > 1 && line[len-2] == '\r')
256 len -= 2;
257 else
258 len--;
259 }
260
261 for (i = 0; i < regs->nr; i++) {
262 struct ff_reg *reg = regs->array + i;
263 if (!regexec_buf(®->re, line, len, 2, pmatch, 0)) {
264 if (reg->negate)
265 return -1;
266 break;
267 }
268 }
269 if (regs->nr <= i)
270 return -1;
271 i = pmatch[1].rm_so >= 0 ? 1 : 0;
272 line += pmatch[i].rm_so;
273 result = pmatch[i].rm_eo - pmatch[i].rm_so;
274 if (result > buffer_size)
275 result = buffer_size;
276 while (result > 0 && (isspace(line[result - 1])))
277 result--;
278 memcpy(buffer, line, result);
279 return result;
280}
281
282void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value, int cflags)
283{
284 int i;
285 struct ff_regs *regs;
286
287 xecfg->find_func = ff_regexp;
288 regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs));
289 for (i = 0, regs->nr = 1; value[i]; i++)
290 if (value[i] == '\n')
291 regs->nr++;
292 ALLOC_ARRAY(regs->array, regs->nr);
293 for (i = 0; i < regs->nr; i++) {
294 struct ff_reg *reg = regs->array + i;
295 const char *ep = strchr(value, '\n'), *expression;
296 char *buffer = NULL;
297
298 reg->negate = (*value == '!');
299 if (reg->negate && i == regs->nr - 1)
300 die("Last expression must not be negated: %s", value);
301 if (*value == '!')
302 value++;
303 if (ep)
304 expression = buffer = xstrndup(value, ep - value);
305 else
306 expression = value;
307 if (regcomp(®->re, expression, cflags))
308 die("Invalid regexp to look for hunk header: %s", expression);
309 free(buffer);
310 value = ep + 1;
311 }
312}
313
314void xdiff_clear_find_func(xdemitconf_t *xecfg)
315{
316 if (xecfg->find_func) {
317 int i;
318 struct ff_regs *regs = xecfg->find_func_priv;
319
320 for (i = 0; i < regs->nr; i++)
321 regfree(®s->array[i].re);
322 free(regs->array);
323 free(regs);
324 xecfg->find_func = NULL;
325 xecfg->find_func_priv = NULL;
326 }
327}
328
329unsigned long xdiff_hash_string(const char *s, size_t len, long flags)
330{
331 return xdl_hash_record(&s, s + len, flags);
332}
333
334int xdiff_compare_lines(const char *l1, long s1,
335 const char *l2, long s2, long flags)
336{
337 return xdl_recmatch(l1, s1, l2, s2, flags);
338}
339
340int git_xmerge_style = -1;
341
342int git_xmerge_config(const char *var, const char *value, void *cb)
343{
344 if (!strcmp(var, "merge.conflictstyle")) {
345 if (!value)
346 die("'%s' is not a boolean", var);
347 if (!strcmp(value, "diff3"))
348 git_xmerge_style = XDL_MERGE_DIFF3;
349 else if (!strcmp(value, "merge"))
350 git_xmerge_style = 0;
351 else
352 die("unknown style '%s' given for '%s'",
353 value, var);
354 return 0;
355 }
356 return git_default_config(var, value, cb);
357}