git-p4: auto-size the block
[git.git] / xdiff-interface.c
blob9315bc0ede11ba0377e27d711e37b6a0ae555c43
1 #include "cache.h"
2 #include "config.h"
3 #include "xdiff-interface.h"
4 #include "xdiff/xtypes.h"
5 #include "xdiff/xdiffi.h"
6 #include "xdiff/xemit.h"
7 #include "xdiff/xmacros.h"
8 #include "xdiff/xutils.h"
10 struct xdiff_emit_state {
11 xdiff_emit_consume_fn consume;
12 void *consume_callback_data;
13 struct strbuf remainder;
16 static int parse_num(char **cp_p, int *num_p)
18 char *cp = *cp_p;
19 int num = 0;
21 while ('0' <= *cp && *cp <= '9')
22 num = num * 10 + *cp++ - '0';
23 if (!(cp - *cp_p))
24 return -1;
25 *cp_p = cp;
26 *num_p = num;
27 return 0;
30 int parse_hunk_header(char *line, int len,
31 int *ob, int *on,
32 int *nb, int *nn)
34 char *cp;
35 cp = line + 4;
36 if (parse_num(&cp, ob)) {
37 bad_line:
38 return error("malformed diff output: %s", line);
40 if (*cp == ',') {
41 cp++;
42 if (parse_num(&cp, on))
43 goto bad_line;
45 else
46 *on = 1;
47 if (*cp++ != ' ' || *cp++ != '+')
48 goto bad_line;
49 if (parse_num(&cp, nb))
50 goto bad_line;
51 if (*cp == ',') {
52 cp++;
53 if (parse_num(&cp, nn))
54 goto bad_line;
56 else
57 *nn = 1;
58 return -!!memcmp(cp, " @@", 3);
61 static void consume_one(void *priv_, char *s, unsigned long size)
63 struct xdiff_emit_state *priv = priv_;
64 char *ep;
65 while (size) {
66 unsigned long this_size;
67 ep = memchr(s, '\n', size);
68 this_size = (ep == NULL) ? size : (ep - s + 1);
69 priv->consume(priv->consume_callback_data, s, this_size);
70 size -= this_size;
71 s += this_size;
75 static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
77 struct xdiff_emit_state *priv = priv_;
78 int i;
80 for (i = 0; i < nbuf; i++) {
81 if (mb[i].ptr[mb[i].size-1] != '\n') {
82 /* Incomplete line */
83 strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
84 continue;
87 /* we have a complete line */
88 if (!priv->remainder.len) {
89 consume_one(priv, mb[i].ptr, mb[i].size);
90 continue;
92 strbuf_add(&priv->remainder, mb[i].ptr, mb[i].size);
93 consume_one(priv, priv->remainder.buf, priv->remainder.len);
94 strbuf_reset(&priv->remainder);
96 if (priv->remainder.len) {
97 consume_one(priv, priv->remainder.buf, priv->remainder.len);
98 strbuf_reset(&priv->remainder);
100 return 0;
104 * Trim down common substring at the end of the buffers,
105 * but end on a complete line.
107 static void trim_common_tail(mmfile_t *a, mmfile_t *b)
109 const int blk = 1024;
110 long trimmed = 0, recovered = 0;
111 char *ap = a->ptr + a->size;
112 char *bp = b->ptr + b->size;
113 long smaller = (a->size < b->size) ? a->size : b->size;
115 while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {
116 trimmed += blk;
117 ap -= blk;
118 bp -= blk;
121 while (recovered < trimmed)
122 if (ap[recovered++] == '\n')
123 break;
124 a->size -= trimmed - recovered;
125 b->size -= trimmed - recovered;
128 int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb)
130 mmfile_t a = *mf1;
131 mmfile_t b = *mf2;
133 if (mf1->size > MAX_XDIFF_SIZE || mf2->size > MAX_XDIFF_SIZE)
134 return -1;
136 if (!xecfg->ctxlen && !(xecfg->flags & XDL_EMIT_FUNCCONTEXT))
137 trim_common_tail(&a, &b);
139 return xdl_diff(&a, &b, xpp, xecfg, xecb);
142 int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
143 xdiff_emit_consume_fn fn, void *consume_callback_data,
144 xpparam_t const *xpp, xdemitconf_t const *xecfg)
146 int ret;
147 struct xdiff_emit_state state;
148 xdemitcb_t ecb;
150 memset(&state, 0, sizeof(state));
151 state.consume = fn;
152 state.consume_callback_data = consume_callback_data;
153 memset(&ecb, 0, sizeof(ecb));
154 ecb.outf = xdiff_outf;
155 ecb.priv = &state;
156 strbuf_init(&state.remainder, 0);
157 ret = xdi_diff(mf1, mf2, xpp, xecfg, &ecb);
158 strbuf_release(&state.remainder);
159 return ret;
162 int read_mmfile(mmfile_t *ptr, const char *filename)
164 struct stat st;
165 FILE *f;
166 size_t sz;
168 if (stat(filename, &st))
169 return error_errno("Could not stat %s", filename);
170 if ((f = fopen(filename, "rb")) == NULL)
171 return error_errno("Could not open %s", filename);
172 sz = xsize_t(st.st_size);
173 ptr->ptr = xmalloc(sz ? sz : 1);
174 if (sz && fread(ptr->ptr, sz, 1, f) != 1) {
175 fclose(f);
176 return error("Could not read %s", filename);
178 fclose(f);
179 ptr->size = sz;
180 return 0;
183 void read_mmblob(mmfile_t *ptr, const struct object_id *oid)
185 unsigned long size;
186 enum object_type type;
188 if (!oidcmp(oid, &null_oid)) {
189 ptr->ptr = xstrdup("");
190 ptr->size = 0;
191 return;
194 ptr->ptr = read_object_file(oid, &type, &size);
195 if (!ptr->ptr || type != OBJ_BLOB)
196 die("unable to read blob object %s", oid_to_hex(oid));
197 ptr->size = size;
200 #define FIRST_FEW_BYTES 8000
201 int buffer_is_binary(const char *ptr, unsigned long size)
203 if (FIRST_FEW_BYTES < size)
204 size = FIRST_FEW_BYTES;
205 return !!memchr(ptr, 0, size);
208 struct ff_regs {
209 int nr;
210 struct ff_reg {
211 regex_t re;
212 int negate;
213 } *array;
216 static long ff_regexp(const char *line, long len,
217 char *buffer, long buffer_size, void *priv)
219 struct ff_regs *regs = priv;
220 regmatch_t pmatch[2];
221 int i;
222 int result;
224 /* Exclude terminating newline (and cr) from matching */
225 if (len > 0 && line[len-1] == '\n') {
226 if (len > 1 && line[len-2] == '\r')
227 len -= 2;
228 else
229 len--;
232 for (i = 0; i < regs->nr; i++) {
233 struct ff_reg *reg = regs->array + i;
234 if (!regexec_buf(&reg->re, line, len, 2, pmatch, 0)) {
235 if (reg->negate)
236 return -1;
237 break;
240 if (regs->nr <= i)
241 return -1;
242 i = pmatch[1].rm_so >= 0 ? 1 : 0;
243 line += pmatch[i].rm_so;
244 result = pmatch[i].rm_eo - pmatch[i].rm_so;
245 if (result > buffer_size)
246 result = buffer_size;
247 while (result > 0 && (isspace(line[result - 1])))
248 result--;
249 memcpy(buffer, line, result);
250 return result;
253 void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value, int cflags)
255 int i;
256 struct ff_regs *regs;
258 xecfg->find_func = ff_regexp;
259 regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs));
260 for (i = 0, regs->nr = 1; value[i]; i++)
261 if (value[i] == '\n')
262 regs->nr++;
263 ALLOC_ARRAY(regs->array, regs->nr);
264 for (i = 0; i < regs->nr; i++) {
265 struct ff_reg *reg = regs->array + i;
266 const char *ep = strchr(value, '\n'), *expression;
267 char *buffer = NULL;
269 reg->negate = (*value == '!');
270 if (reg->negate && i == regs->nr - 1)
271 die("Last expression must not be negated: %s", value);
272 if (*value == '!')
273 value++;
274 if (ep)
275 expression = buffer = xstrndup(value, ep - value);
276 else
277 expression = value;
278 if (regcomp(&reg->re, expression, cflags))
279 die("Invalid regexp to look for hunk header: %s", expression);
280 free(buffer);
281 value = ep + 1;
285 void xdiff_clear_find_func(xdemitconf_t *xecfg)
287 if (xecfg->find_func) {
288 int i;
289 struct ff_regs *regs = xecfg->find_func_priv;
291 for (i = 0; i < regs->nr; i++)
292 regfree(&regs->array[i].re);
293 free(regs->array);
294 free(regs);
295 xecfg->find_func = NULL;
296 xecfg->find_func_priv = NULL;
300 unsigned long xdiff_hash_string(const char *s, size_t len, long flags)
302 return xdl_hash_record(&s, s + len, flags);
305 int xdiff_compare_lines(const char *l1, long s1,
306 const char *l2, long s2, long flags)
308 return xdl_recmatch(l1, s1, l2, s2, flags);
311 int git_xmerge_style = -1;
313 int git_xmerge_config(const char *var, const char *value, void *cb)
315 if (!strcmp(var, "merge.conflictstyle")) {
316 if (!value)
317 die("'%s' is not a boolean", var);
318 if (!strcmp(value, "diff3"))
319 git_xmerge_style = XDL_MERGE_DIFF3;
320 else if (!strcmp(value, "merge"))
321 git_xmerge_style = 0;
322 else
323 die("unknown style '%s' given for '%s'",
324 value, var);
325 return 0;
327 return git_default_config(var, value, cb);