refactor duplicated fill_mm() in checkout and merge-recursive
[git/git.git] / xdiff-interface.c
CommitLineData
d9ea73e0
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1#include "cache.h"
2#include "xdiff-interface.h"
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3#include "xdiff/xtypes.h"
4#include "xdiff/xdiffi.h"
5#include "xdiff/xemit.h"
6#include "xdiff/xmacros.h"
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7
8struct xdiff_emit_state {
9 xdiff_emit_consume_fn consume;
10 void *consume_callback_data;
11 struct strbuf remainder;
12};
d9ea73e0 13
a0fd3146 14static int parse_num(char **cp_p, int *num_p)
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15{
16 char *cp = *cp_p;
a0fd3146 17 int num = 0;
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18
19 while ('0' <= *cp && *cp <= '9')
20 num = num * 10 + *cp++ - '0';
eb3a9dd3 21 if (!(cp - *cp_p))
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22 return -1;
23 *cp_p = cp;
24 *num_p = num;
25 return 0;
26}
27
28int parse_hunk_header(char *line, int len,
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29 int *ob, int *on,
30 int *nb, int *nn)
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31{
32 char *cp;
33 cp = line + 4;
34 if (parse_num(&cp, ob)) {
35 bad_line:
36 return error("malformed diff output: %s", line);
37 }
38 if (*cp == ',') {
39 cp++;
40 if (parse_num(&cp, on))
41 goto bad_line;
42 }
43 else
44 *on = 1;
45 if (*cp++ != ' ' || *cp++ != '+')
46 goto bad_line;
47 if (parse_num(&cp, nb))
48 goto bad_line;
49 if (*cp == ',') {
50 cp++;
51 if (parse_num(&cp, nn))
52 goto bad_line;
53 }
54 else
55 *nn = 1;
56 return -!!memcmp(cp, " @@", 3);
57}
58
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59static void consume_one(void *priv_, char *s, unsigned long size)
60{
61 struct xdiff_emit_state *priv = priv_;
62 char *ep;
63 while (size) {
64 unsigned long this_size;
65 ep = memchr(s, '\n', size);
66 this_size = (ep == NULL) ? size : (ep - s + 1);
8a3f524b 67 priv->consume(priv->consume_callback_data, s, this_size);
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68 size -= this_size;
69 s += this_size;
70 }
71}
72
c99db9d2 73static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
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74{
75 struct xdiff_emit_state *priv = priv_;
76 int i;
77
78 for (i = 0; i < nbuf; i++) {
79 if (mb[i].ptr[mb[i].size-1] != '\n') {
80 /* Incomplete line */
b4637760 81 strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
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82 continue;
83 }
84
85 /* we have a complete line */
b4637760 86 if (!priv->remainder.len) {
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87 consume_one(priv, mb[i].ptr, mb[i].size);
88 continue;
89 }
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BD
90 strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
91 consume_one(priv, priv->remainder.buf, priv->remainder.len);
92 strbuf_reset(&priv->remainder);
d9ea73e0 93 }
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BD
94 if (priv->remainder.len) {
95 consume_one(priv, priv->remainder.buf, priv->remainder.len);
96 strbuf_reset(&priv->remainder);
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97 }
98 return 0;
99}
7cab5883 100
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101/*
102 * Trim down common substring at the end of the buffers,
103 * but leave at least ctx lines at the end.
104 */
29ab27f4 105static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
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106{
107 const int blk = 1024;
52499977 108 long trimmed = 0, recovered = 0;
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109 char *ap = a->ptr + a->size;
110 char *bp = b->ptr + b->size;
111 long smaller = (a->size < b->size) ? a->size : b->size;
112
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LT
113 if (ctx)
114 return;
115
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116 while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {
117 trimmed += blk;
118 ap -= blk;
119 bp -= blk;
120 }
121
d2f82950 122 while (recovered < trimmed)
52499977 123 if (ap[recovered++] == '\n')
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LT
124 break;
125 a->size -= trimmed - recovered;
126 b->size -= trimmed - recovered;
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127}
128
c279d7e9
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129int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb)
130{
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131 mmfile_t a = *mf1;
132 mmfile_t b = *mf2;
133
134 trim_common_tail(&a, &b, xecfg->ctxlen);
135
136 return xdl_diff(&a, &b, xpp, xecfg, xecb);
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137}
138
c99db9d2 139int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
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140 xdiff_emit_consume_fn fn, void *consume_callback_data,
141 xpparam_t const *xpp,
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142 xdemitconf_t const *xecfg, xdemitcb_t *xecb)
143{
144 int ret;
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145 struct xdiff_emit_state state;
146
147 memset(&state, 0, sizeof(state));
148 state.consume = fn;
149 state.consume_callback_data = consume_callback_data;
c99db9d2 150 xecb->outf = xdiff_outf;
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151 xecb->priv = &state;
152 strbuf_init(&state.remainder, 0);
c99db9d2 153 ret = xdi_diff(mf1, mf2, xpp, xecfg, xecb);
8a3f524b 154 strbuf_release(&state.remainder);
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BD
155 return ret;
156}
157
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RS
158struct xdiff_emit_hunk_state {
159 xdiff_emit_hunk_consume_fn consume;
160 void *consume_callback_data;
161};
162
163static int process_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
164 xdemitconf_t const *xecfg)
165{
166 long s1, s2, same, p_next, t_next;
167 xdchange_t *xch, *xche;
168 struct xdiff_emit_hunk_state *state = ecb->priv;
169 xdiff_emit_hunk_consume_fn fn = state->consume;
170 void *consume_callback_data = state->consume_callback_data;
171
172 for (xch = xscr; xch; xch = xche->next) {
173 xche = xdl_get_hunk(xch, xecfg);
174
175 s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0);
176 s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0);
177 same = s2 + XDL_MAX(xch->i1 - s1, 0);
178 p_next = xche->i1 + xche->chg1;
179 t_next = xche->i2 + xche->chg2;
180
181 fn(consume_callback_data, same, p_next, t_next);
182 }
183 return 0;
184}
185
186int xdi_diff_hunks(mmfile_t *mf1, mmfile_t *mf2,
187 xdiff_emit_hunk_consume_fn fn, void *consume_callback_data,
188 xpparam_t const *xpp, xdemitconf_t *xecfg)
189{
190 struct xdiff_emit_hunk_state state;
191 xdemitcb_t ecb;
192
193 memset(&state, 0, sizeof(state));
194 memset(&ecb, 0, sizeof(ecb));
195 state.consume = fn;
196 state.consume_callback_data = consume_callback_data;
197 xecfg->emit_func = (void (*)())process_diff;
198 ecb.priv = &state;
199 return xdi_diff(mf1, mf2, xpp, xecfg, &ecb);
200}
201
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202int read_mmfile(mmfile_t *ptr, const char *filename)
203{
204 struct stat st;
205 FILE *f;
dc49cd76 206 size_t sz;
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207
208 if (stat(filename, &st))
209 return error("Could not stat %s", filename);
210 if ((f = fopen(filename, "rb")) == NULL)
211 return error("Could not open %s", filename);
dc49cd76 212 sz = xsize_t(st.st_size);
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213 ptr->ptr = xmalloc(sz ? sz : 1);
214 if (sz && fread(ptr->ptr, sz, 1, f) != 1)
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215 return error("Could not read %s", filename);
216 fclose(f);
dc49cd76 217 ptr->size = sz;
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218 return 0;
219}
220
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221void read_mmblob(mmfile_t *ptr, const unsigned char *sha1)
222{
223 unsigned long size;
224 enum object_type type;
225
226 if (!hashcmp(sha1, null_sha1)) {
227 ptr->ptr = xstrdup("");
228 ptr->size = 0;
229 return;
230 }
231
232 ptr->ptr = read_sha1_file(sha1, &type, &size);
233 if (!ptr->ptr || type != OBJ_BLOB)
234 die("unable to read blob object %s", sha1_to_hex(sha1));
235 ptr->size = size;
236}
237
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238#define FIRST_FEW_BYTES 8000
239int buffer_is_binary(const char *ptr, unsigned long size)
240{
241 if (FIRST_FEW_BYTES < size)
242 size = FIRST_FEW_BYTES;
243 return !!memchr(ptr, 0, size);
244}
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245
246struct ff_regs {
247 int nr;
248 struct ff_reg {
249 regex_t re;
250 int negate;
251 } *array;
252};
253
254static long ff_regexp(const char *line, long len,
255 char *buffer, long buffer_size, void *priv)
256{
a5a5a048 257 char *line_buffer;
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258 struct ff_regs *regs = priv;
259 regmatch_t pmatch[2];
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260 int i;
261 int result = -1;
f258475a 262
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263 /* Exclude terminating newline (and cr) from matching */
264 if (len > 0 && line[len-1] == '\n') {
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265 if (len > 1 && line[len-2] == '\r')
266 len -= 2;
267 else
268 len--;
269 }
270
271 line_buffer = xstrndup(line, len); /* make NUL terminated */
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272
273 for (i = 0; i < regs->nr; i++) {
274 struct ff_reg *reg = regs->array + i;
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275 if (!regexec(&reg->re, line_buffer, 2, pmatch, 0)) {
276 if (reg->negate)
277 goto fail;
278 break;
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279 }
280 }
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281 if (regs->nr <= i)
282 goto fail;
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283 i = pmatch[1].rm_so >= 0 ? 1 : 0;
284 line += pmatch[i].rm_so;
285 result = pmatch[i].rm_eo - pmatch[i].rm_so;
286 if (result > buffer_size)
287 result = buffer_size;
288 else
3d8dccd7 289 while (result > 0 && (isspace(line[result - 1])))
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290 result--;
291 memcpy(buffer, line, result);
3d8dccd7 292 fail:
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293 free(line_buffer);
294 return result;
295}
296
a013585b 297void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value, int cflags)
f258475a
JH
298{
299 int i;
300 struct ff_regs *regs;
301
302 xecfg->find_func = ff_regexp;
303 regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs));
304 for (i = 0, regs->nr = 1; value[i]; i++)
305 if (value[i] == '\n')
306 regs->nr++;
307 regs->array = xmalloc(regs->nr * sizeof(struct ff_reg));
308 for (i = 0; i < regs->nr; i++) {
309 struct ff_reg *reg = regs->array + i;
310 const char *ep = strchr(value, '\n'), *expression;
311 char *buffer = NULL;
312
313 reg->negate = (*value == '!');
314 if (reg->negate && i == regs->nr - 1)
315 die("Last expression must not be negated: %s", value);
316 if (*value == '!')
317 value++;
318 if (ep)
319 expression = buffer = xstrndup(value, ep - value);
320 else
321 expression = value;
a013585b 322 if (regcomp(&reg->re, expression, cflags))
f258475a 323 die("Invalid regexp to look for hunk header: %s", expression);
8e0f7003 324 free(buffer);
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JH
325 value = ep + 1;
326 }
327}
b5412484 328
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RS
329void xdiff_clear_find_func(xdemitconf_t *xecfg)
330{
331 if (xecfg->find_func) {
332 int i;
333 struct ff_regs *regs = xecfg->find_func_priv;
334
335 for (i = 0; i < regs->nr; i++)
336 regfree(&regs->array[i].re);
337 free(regs->array);
338 free(regs);
339 xecfg->find_func = NULL;
340 xecfg->find_func_priv = NULL;
341 }
342}
343
b5412484
JH
344int git_xmerge_style = -1;
345
346int git_xmerge_config(const char *var, const char *value, void *cb)
347{
348 if (!strcasecmp(var, "merge.conflictstyle")) {
349 if (!value)
350 die("'%s' is not a boolean", var);
351 if (!strcmp(value, "diff3"))
352 git_xmerge_style = XDL_MERGE_DIFF3;
353 else if (!strcmp(value, "merge"))
354 git_xmerge_style = 0;
355 else
356 die("unknown style '%s' given for '%s'",
357 value, var);
358 return 0;
359 }
360 return git_default_config(var, value, cb);
361}