Merge branch 'maint'
[git/git.git] / xdiff-interface.c
CommitLineData
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1#include "cache.h"
2#include "xdiff-interface.h"
3
a0fd3146 4static int parse_num(char **cp_p, int *num_p)
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5{
6 char *cp = *cp_p;
a0fd3146 7 int num = 0;
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8 int read_some;
9
10 while ('0' <= *cp && *cp <= '9')
11 num = num * 10 + *cp++ - '0';
12 if (!(read_some = cp - *cp_p))
13 return -1;
14 *cp_p = cp;
15 *num_p = num;
16 return 0;
17}
18
19int parse_hunk_header(char *line, int len,
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20 int *ob, int *on,
21 int *nb, int *nn)
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22{
23 char *cp;
24 cp = line + 4;
25 if (parse_num(&cp, ob)) {
26 bad_line:
27 return error("malformed diff output: %s", line);
28 }
29 if (*cp == ',') {
30 cp++;
31 if (parse_num(&cp, on))
32 goto bad_line;
33 }
34 else
35 *on = 1;
36 if (*cp++ != ' ' || *cp++ != '+')
37 goto bad_line;
38 if (parse_num(&cp, nb))
39 goto bad_line;
40 if (*cp == ',') {
41 cp++;
42 if (parse_num(&cp, nn))
43 goto bad_line;
44 }
45 else
46 *nn = 1;
47 return -!!memcmp(cp, " @@", 3);
48}
49
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50static void consume_one(void *priv_, char *s, unsigned long size)
51{
52 struct xdiff_emit_state *priv = priv_;
53 char *ep;
54 while (size) {
55 unsigned long this_size;
56 ep = memchr(s, '\n', size);
57 this_size = (ep == NULL) ? size : (ep - s + 1);
58 priv->consume(priv, s, this_size);
59 size -= this_size;
60 s += this_size;
61 }
62}
63
64int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
65{
66 struct xdiff_emit_state *priv = priv_;
67 int i;
68
69 for (i = 0; i < nbuf; i++) {
70 if (mb[i].ptr[mb[i].size-1] != '\n') {
71 /* Incomplete line */
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72 priv->remainder = xrealloc(priv->remainder,
73 priv->remainder_size +
74 mb[i].size);
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75 memcpy(priv->remainder + priv->remainder_size,
76 mb[i].ptr, mb[i].size);
77 priv->remainder_size += mb[i].size;
78 continue;
79 }
80
81 /* we have a complete line */
82 if (!priv->remainder) {
83 consume_one(priv, mb[i].ptr, mb[i].size);
84 continue;
85 }
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86 priv->remainder = xrealloc(priv->remainder,
87 priv->remainder_size +
88 mb[i].size);
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89 memcpy(priv->remainder + priv->remainder_size,
90 mb[i].ptr, mb[i].size);
91 consume_one(priv, priv->remainder,
92 priv->remainder_size + mb[i].size);
93 free(priv->remainder);
94 priv->remainder = NULL;
95 priv->remainder_size = 0;
96 }
97 if (priv->remainder) {
98 consume_one(priv, priv->remainder, priv->remainder_size);
99 free(priv->remainder);
100 priv->remainder = NULL;
101 priv->remainder_size = 0;
102 }
103 return 0;
104}
7cab5883 105
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106/*
107 * Trim down common substring at the end of the buffers,
108 * but leave at least ctx lines at the end.
109 */
29ab27f4 110static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
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111{
112 const int blk = 1024;
52499977 113 long trimmed = 0, recovered = 0;
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114 char *ap = a->ptr + a->size;
115 char *bp = b->ptr + b->size;
116 long smaller = (a->size < b->size) ? a->size : b->size;
117
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118 if (ctx)
119 return;
120
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121 while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {
122 trimmed += blk;
123 ap -= blk;
124 bp -= blk;
125 }
126
d2f82950 127 while (recovered < trimmed)
52499977 128 if (ap[recovered++] == '\n')
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129 break;
130 a->size -= trimmed - recovered;
131 b->size -= trimmed - recovered;
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132}
133
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134int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb)
135{
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136 mmfile_t a = *mf1;
137 mmfile_t b = *mf2;
138
139 trim_common_tail(&a, &b, xecfg->ctxlen);
140
141 return xdl_diff(&a, &b, xpp, xecfg, xecb);
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142}
143
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144int read_mmfile(mmfile_t *ptr, const char *filename)
145{
146 struct stat st;
147 FILE *f;
dc49cd76 148 size_t sz;
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149
150 if (stat(filename, &st))
151 return error("Could not stat %s", filename);
152 if ((f = fopen(filename, "rb")) == NULL)
153 return error("Could not open %s", filename);
dc49cd76 154 sz = xsize_t(st.st_size);
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155 ptr->ptr = xmalloc(sz ? sz : 1);
156 if (sz && fread(ptr->ptr, sz, 1, f) != 1)
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157 return error("Could not read %s", filename);
158 fclose(f);
dc49cd76 159 ptr->size = sz;
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160 return 0;
161}
162
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163#define FIRST_FEW_BYTES 8000
164int buffer_is_binary(const char *ptr, unsigned long size)
165{
166 if (FIRST_FEW_BYTES < size)
167 size = FIRST_FEW_BYTES;
168 return !!memchr(ptr, 0, size);
169}
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170
171struct ff_regs {
172 int nr;
173 struct ff_reg {
174 regex_t re;
175 int negate;
176 } *array;
177};
178
179static long ff_regexp(const char *line, long len,
180 char *buffer, long buffer_size, void *priv)
181{
182 char *line_buffer = xstrndup(line, len); /* make NUL terminated */
183 struct ff_regs *regs = priv;
184 regmatch_t pmatch[2];
185 int result = 0, i;
186
187 for (i = 0; i < regs->nr; i++) {
188 struct ff_reg *reg = regs->array + i;
189 if (reg->negate ^ !!regexec(&reg->re,
190 line_buffer, 2, pmatch, 0)) {
191 free(line_buffer);
192 return -1;
193 }
194 }
195 i = pmatch[1].rm_so >= 0 ? 1 : 0;
196 line += pmatch[i].rm_so;
197 result = pmatch[i].rm_eo - pmatch[i].rm_so;
198 if (result > buffer_size)
199 result = buffer_size;
200 else
201 while (result > 0 && (isspace(line[result - 1]) ||
202 line[result - 1] == '\n'))
203 result--;
204 memcpy(buffer, line, result);
205 free(line_buffer);
206 return result;
207}
208
209void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value)
210{
211 int i;
212 struct ff_regs *regs;
213
214 xecfg->find_func = ff_regexp;
215 regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs));
216 for (i = 0, regs->nr = 1; value[i]; i++)
217 if (value[i] == '\n')
218 regs->nr++;
219 regs->array = xmalloc(regs->nr * sizeof(struct ff_reg));
220 for (i = 0; i < regs->nr; i++) {
221 struct ff_reg *reg = regs->array + i;
222 const char *ep = strchr(value, '\n'), *expression;
223 char *buffer = NULL;
224
225 reg->negate = (*value == '!');
226 if (reg->negate && i == regs->nr - 1)
227 die("Last expression must not be negated: %s", value);
228 if (*value == '!')
229 value++;
230 if (ep)
231 expression = buffer = xstrndup(value, ep - value);
232 else
233 expression = value;
234 if (regcomp(&reg->re, expression, 0))
235 die("Invalid regexp to look for hunk header: %s", expression);
8e0f7003 236 free(buffer);
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237 value = ep + 1;
238 }
239}