Code

parse_tag_buffer: don't parse invalid tags
[git.git] / xdiff-interface.c
1 #include "cache.h"
2 #include "xdiff-interface.h"
4 static int parse_num(char **cp_p, int *num_p)
5 {
6         char *cp = *cp_p;
7         int num = 0;
8         int read_some;
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 }
19 int parse_hunk_header(char *line, int len,
20                       int *ob, int *on,
21                       int *nb, int *nn)
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 }
50 static 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 }
64 int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
65 {
66         struct xdiff_emit_state *priv = priv_;
67         int i;
69         for (i = 0; i < nbuf; i++) {
70                 if (mb[i].ptr[mb[i].size-1] != '\n') {
71                         /* Incomplete line */
72                         priv->remainder = xrealloc(priv->remainder,
73                                                    priv->remainder_size +
74                                                    mb[i].size);
75                         memcpy(priv->remainder + priv->remainder_size,
76                                mb[i].ptr, mb[i].size);
77                         priv->remainder_size += mb[i].size;
78                         continue;
79                 }
81                 /* we have a complete line */
82                 if (!priv->remainder) {
83                         consume_one(priv, mb[i].ptr, mb[i].size);
84                         continue;
85                 }
86                 priv->remainder = xrealloc(priv->remainder,
87                                            priv->remainder_size +
88                                            mb[i].size);
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;
106 /*
107  * Trim down common substring at the end of the buffers,
108  * but leave at least ctx lines at the end.
109  */
110 static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
112         const int blk = 1024;
113         long trimmed = 0, recovered = 0;
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;
118         if (ctx)
119                 return;
121         while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {
122                 trimmed += blk;
123                 ap -= blk;
124                 bp -= blk;
125         }
127         while (recovered < trimmed)
128                 if (ap[recovered++] == '\n')
129                         break;
130         a->size -= trimmed - recovered;
131         b->size -= trimmed - recovered;
134 int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *xecb)
136         mmfile_t a = *mf1;
137         mmfile_t b = *mf2;
139         trim_common_tail(&a, &b, xecfg->ctxlen);
141         return xdl_diff(&a, &b, xpp, xecfg, xecb);
144 int read_mmfile(mmfile_t *ptr, const char *filename)
146         struct stat st;
147         FILE *f;
148         size_t sz;
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);
154         sz = xsize_t(st.st_size);
155         ptr->ptr = xmalloc(sz);
156         if (fread(ptr->ptr, sz, 1, f) != 1)
157                 return error("Could not read %s", filename);
158         fclose(f);
159         ptr->size = sz;
160         return 0;
163 #define FIRST_FEW_BYTES 8000
164 int buffer_is_binary(const char *ptr, unsigned long size)
166         if (FIRST_FEW_BYTES < size)
167                 size = FIRST_FEW_BYTES;
168         return !!memchr(ptr, 0, size);
171 struct ff_regs {
172         int nr;
173         struct ff_reg {
174                 regex_t re;
175                 int negate;
176         } *array;
177 };
179 static long ff_regexp(const char *line, long len,
180                 char *buffer, long buffer_size, void *priv)
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;
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;
209 void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value)
211         int i;
212         struct ff_regs *regs;
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;
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);
236                 if (buffer)
237                         free(buffer);
238                 value = ep + 1;
239         }