freshlybakedca.ke
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1#include "git-compat-util.h"
2#include "line-range.h"
3#include "xdiff-interface.h"
4#include "userdiff.h"
5
6/*
7 * Parse one item in the -L option
8 *
9 * 'begin' is applicable only to relative range anchors. Absolute anchors
10 * ignore this value.
11 *
12 * When parsing "-L A,B", parse_loc() is called once for A and once for B.
13 *
14 * When parsing A, 'begin' must be a negative number, the absolute value of
15 * which is the line at which relative start-of-range anchors should be
16 * based. Beginning of file is represented by -1.
17 *
18 * When parsing B, 'begin' must be the positive line number immediately
19 * following the line computed for 'A'.
20 */
21static const char *parse_loc(const char *spec, nth_line_fn_t nth_line,
22 void *data, long lines, long begin, long *ret)
23{
24 char *term;
25 const char *line;
26 long num;
27 int reg_error;
28 regex_t regexp;
29 regmatch_t match[1];
30
31 /* Allow "-L <something>,+20" to mean starting at <something>
32 * for 20 lines, or "-L <something>,-5" for 5 lines ending at
33 * <something>.
34 */
35 if (1 <= begin && (spec[0] == '+' || spec[0] == '-')) {
36 num = strtol(spec + 1, &term, 10);
37 if (term != spec + 1) {
38 if (!ret)
39 return term;
40 if (num == 0)
41 die("-L invalid empty range");
42 if (spec[0] == '-')
43 num = 0 - num;
44 if (0 < num)
45 *ret = begin + num - 2;
46 else if (!num)
47 *ret = begin;
48 else
49 *ret = begin + num > 0 ? begin + num : 1;
50 return term;
51 }
52 return spec;
53 }
54 num = strtol(spec, &term, 10);
55 if (term != spec) {
56 if (ret) {
57 if (num <= 0)
58 die("-L invalid line number: %ld", num);
59 *ret = num;
60 }
61 return term;
62 }
63
64 if (begin < 0) {
65 if (spec[0] != '^')
66 begin = -begin;
67 else {
68 begin = 1;
69 spec++;
70 }
71 }
72
73 if (spec[0] != '/')
74 return spec;
75
76 /* it could be a regexp of form /.../ */
77 for (term = (char *) spec + 1; *term && *term != '/'; term++) {
78 if (*term == '\\')
79 term++;
80 }
81 if (*term != '/')
82 return spec;
83
84 /* in the scan-only case we are not interested in the regex */
85 if (!ret)
86 return term+1;
87
88 /* try [spec+1 .. term-1] as regexp */
89 *term = 0;
90 begin--; /* input is in human terms */
91 line = nth_line(data, begin);
92
93 if (!(reg_error = regcomp(®exp, spec + 1, REG_NEWLINE)) &&
94 !(reg_error = regexec(®exp, line, 1, match, 0))) {
95 const char *cp = line + match[0].rm_so;
96 const char *nline;
97
98 while (begin++ < lines) {
99 nline = nth_line(data, begin);
100 if (line <= cp && cp < nline)
101 break;
102 line = nline;
103 }
104 *ret = begin;
105 regfree(®exp);
106 *term++ = '/';
107 return term;
108 }
109 else {
110 char errbuf[1024];
111 regerror(reg_error, ®exp, errbuf, 1024);
112 die("-L parameter '%s' starting at line %ld: %s",
113 spec + 1, begin + 1, errbuf);
114 }
115}
116
117static int match_funcname(xdemitconf_t *xecfg, const char *bol, const char *eol)
118{
119 if (xecfg) {
120 char buf[1];
121 return xecfg->find_func(bol, eol - bol, buf, 1,
122 xecfg->find_func_priv) >= 0;
123 }
124
125 if (bol == eol)
126 return 0;
127 if (isalpha(*bol) || *bol == '_' || *bol == '$')
128 return 1;
129 return 0;
130}
131
132static const char *find_funcname_matching_regexp(xdemitconf_t *xecfg, const char *start,
133 regex_t *regexp)
134{
135 int reg_error;
136 regmatch_t match[1];
137 while (*start) {
138 const char *bol, *eol;
139 reg_error = regexec(regexp, start, 1, match, 0);
140 if (reg_error == REG_NOMATCH)
141 return NULL;
142 else if (reg_error) {
143 char errbuf[1024];
144 regerror(reg_error, regexp, errbuf, 1024);
145 die("-L parameter: regexec() failed: %s", errbuf);
146 }
147 /* determine extent of line matched */
148 bol = start+match[0].rm_so;
149 eol = start+match[0].rm_eo;
150 while (bol > start && *--bol != '\n')
151 ; /* nothing */
152 if (*bol == '\n')
153 bol++;
154 while (*eol && *eol != '\n')
155 eol++;
156 if (*eol == '\n')
157 eol++;
158 /* is it a funcname line? */
159 if (match_funcname(xecfg, (char*) bol, (char*) eol))
160 return bol;
161 start = eol;
162 }
163 return NULL;
164}
165
166static const char *parse_range_funcname(
167 const char *arg, nth_line_fn_t nth_line_cb,
168 void *cb_data, long lines, long anchor, long *begin, long *end,
169 const char *path, struct index_state *istate)
170{
171 char *pattern;
172 const char *term;
173 struct userdiff_driver *drv;
174 xdemitconf_t *xecfg = NULL;
175 const char *start;
176 const char *p;
177 int reg_error;
178 regex_t regexp;
179
180 if (*arg == '^') {
181 anchor = 1;
182 arg++;
183 }
184
185 assert(*arg == ':');
186 term = arg+1;
187 while (*term && *term != ':') {
188 if (*term == '\\' && *(term+1))
189 term++;
190 term++;
191 }
192 if (term == arg+1)
193 return NULL;
194 if (!begin) /* skip_range_arg case */
195 return term;
196
197 pattern = xstrndup(arg+1, term-(arg+1));
198
199 anchor--; /* input is in human terms */
200 start = nth_line_cb(cb_data, anchor);
201
202 drv = userdiff_find_by_path(istate, path);
203 if (drv && drv->funcname.pattern) {
204 const struct userdiff_funcname *pe = &drv->funcname;
205 CALLOC_ARRAY(xecfg, 1);
206 xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
207 }
208
209 reg_error = regcomp(®exp, pattern, REG_NEWLINE);
210 if (reg_error) {
211 char errbuf[1024];
212 regerror(reg_error, ®exp, errbuf, 1024);
213 die("-L parameter '%s': %s", pattern, errbuf);
214 }
215
216 p = find_funcname_matching_regexp(xecfg, (char*) start, ®exp);
217 if (!p)
218 die("-L parameter '%s' starting at line %ld: no match",
219 pattern, anchor + 1);
220 *begin = 0;
221 while (p > nth_line_cb(cb_data, *begin))
222 (*begin)++;
223
224 if (*begin >= lines)
225 die("-L parameter '%s' matches at EOF", pattern);
226
227 *end = *begin+1;
228 while (*end < lines) {
229 const char *bol = nth_line_cb(cb_data, *end);
230 const char *eol = nth_line_cb(cb_data, *end+1);
231 if (match_funcname(xecfg, bol, eol))
232 break;
233 (*end)++;
234 }
235
236 regfree(®exp);
237 if (xecfg)
238 xdiff_clear_find_func(xecfg);
239 free(xecfg);
240 free(pattern);
241
242 /* compensate for 1-based numbering */
243 (*begin)++;
244
245 return term;
246}
247
248int parse_range_arg(const char *arg, nth_line_fn_t nth_line_cb,
249 void *cb_data, long lines, long anchor,
250 long *begin, long *end,
251 const char *path, struct index_state *istate)
252{
253 *begin = *end = 0;
254
255 if (anchor < 1)
256 anchor = 1;
257 if (anchor > lines)
258 anchor = lines + 1;
259
260 if (*arg == ':' || (*arg == '^' && *(arg + 1) == ':')) {
261 arg = parse_range_funcname(arg, nth_line_cb, cb_data,
262 lines, anchor, begin, end,
263 path, istate);
264 if (!arg || *arg)
265 return -1;
266 return 0;
267 }
268
269 arg = parse_loc(arg, nth_line_cb, cb_data, lines, -anchor, begin);
270
271 if (*arg == ',')
272 arg = parse_loc(arg + 1, nth_line_cb, cb_data, lines, *begin + 1, end);
273
274 if (*arg)
275 return -1;
276
277 if (*begin && *end && *end < *begin) {
278 SWAP(*end, *begin);
279 }
280
281 return 0;
282}
283
284const char *skip_range_arg(const char *arg, struct index_state *istate)
285{
286 if (*arg == ':' || (*arg == '^' && *(arg + 1) == ':'))
287 return parse_range_funcname(arg, NULL, NULL,
288 0, 0, NULL, NULL,
289 NULL, istate);
290
291 arg = parse_loc(arg, NULL, NULL, 0, -1, NULL);
292
293 if (*arg == ',')
294 arg = parse_loc(arg+1, NULL, NULL, 0, 0, NULL);
295
296 return arg;
297}