Start preparing for 1.8.4.2
[alt-git.git] / line-range.c
blob3942475c2fc8e48c7f0a2d7808f77a4f71a1cde6
1 #include "git-compat-util.h"
2 #include "line-range.h"
3 #include "xdiff-interface.h"
4 #include "strbuf.h"
5 #include "userdiff.h"
7 /*
8 * Parse one item in the -L option
9 */
10 static const char *parse_loc(const char *spec, nth_line_fn_t nth_line,
11 void *data, long lines, long begin, long *ret)
13 char *term;
14 const char *line;
15 long num;
16 int reg_error;
17 regex_t regexp;
18 regmatch_t match[1];
20 /* Allow "-L <something>,+20" to mean starting at <something>
21 * for 20 lines, or "-L <something>,-5" for 5 lines ending at
22 * <something>.
24 if (1 < begin && (spec[0] == '+' || spec[0] == '-')) {
25 num = strtol(spec + 1, &term, 10);
26 if (term != spec + 1) {
27 if (!ret)
28 return term;
29 if (spec[0] == '-')
30 num = 0 - num;
31 if (0 < num)
32 *ret = begin + num - 2;
33 else if (!num)
34 *ret = begin;
35 else
36 *ret = begin + num;
37 return term;
39 return spec;
41 num = strtol(spec, &term, 10);
42 if (term != spec) {
43 if (ret)
44 *ret = num;
45 return term;
47 if (spec[0] != '/')
48 return spec;
50 /* it could be a regexp of form /.../ */
51 for (term = (char *) spec + 1; *term && *term != '/'; term++) {
52 if (*term == '\\')
53 term++;
55 if (*term != '/')
56 return spec;
58 /* in the scan-only case we are not interested in the regex */
59 if (!ret)
60 return term+1;
62 /* try [spec+1 .. term-1] as regexp */
63 *term = 0;
64 begin--; /* input is in human terms */
65 line = nth_line(data, begin);
67 if (!(reg_error = regcomp(&regexp, spec + 1, REG_NEWLINE)) &&
68 !(reg_error = regexec(&regexp, line, 1, match, 0))) {
69 const char *cp = line + match[0].rm_so;
70 const char *nline;
72 while (begin++ < lines) {
73 nline = nth_line(data, begin);
74 if (line <= cp && cp < nline)
75 break;
76 line = nline;
78 *ret = begin;
79 regfree(&regexp);
80 *term++ = '/';
81 return term;
83 else {
84 char errbuf[1024];
85 regerror(reg_error, &regexp, errbuf, 1024);
86 die("-L parameter '%s': %s", spec + 1, errbuf);
90 static int match_funcname(xdemitconf_t *xecfg, const char *bol, const char *eol)
92 if (xecfg) {
93 char buf[1];
94 return xecfg->find_func(bol, eol - bol, buf, 1,
95 xecfg->find_func_priv) >= 0;
98 if (bol == eol)
99 return 0;
100 if (isalpha(*bol) || *bol == '_' || *bol == '$')
101 return 1;
102 return 0;
105 static const char *find_funcname_matching_regexp(xdemitconf_t *xecfg, const char *start,
106 regex_t *regexp)
108 int reg_error;
109 regmatch_t match[1];
110 while (1) {
111 const char *bol, *eol;
112 reg_error = regexec(regexp, start, 1, match, 0);
113 if (reg_error == REG_NOMATCH)
114 return NULL;
115 else if (reg_error) {
116 char errbuf[1024];
117 regerror(reg_error, regexp, errbuf, 1024);
118 die("-L parameter: regexec() failed: %s", errbuf);
120 /* determine extent of line matched */
121 bol = start+match[0].rm_so;
122 eol = start+match[0].rm_eo;
123 while (bol > start && *bol != '\n')
124 bol--;
125 if (*bol == '\n')
126 bol++;
127 while (*eol && *eol != '\n')
128 eol++;
129 if (*eol == '\n')
130 eol++;
131 /* is it a funcname line? */
132 if (match_funcname(xecfg, (char*) bol, (char*) eol))
133 return bol;
134 start = eol;
138 static const char *parse_range_funcname(const char *arg, nth_line_fn_t nth_line_cb,
139 void *cb_data, long lines, long *begin, long *end,
140 const char *path)
142 char *pattern;
143 const char *term;
144 struct userdiff_driver *drv;
145 xdemitconf_t *xecfg = NULL;
146 const char *start;
147 const char *p;
148 int reg_error;
149 regex_t regexp;
151 assert(*arg == ':');
152 term = arg+1;
153 while (*term && *term != ':') {
154 if (*term == '\\' && *(term+1))
155 term++;
156 term++;
158 if (term == arg+1)
159 return NULL;
160 if (!begin) /* skip_range_arg case */
161 return term;
163 pattern = xstrndup(arg+1, term-(arg+1));
165 start = nth_line_cb(cb_data, 0);
167 drv = userdiff_find_by_path(path);
168 if (drv && drv->funcname.pattern) {
169 const struct userdiff_funcname *pe = &drv->funcname;
170 xecfg = xcalloc(1, sizeof(*xecfg));
171 xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
174 reg_error = regcomp(&regexp, pattern, REG_NEWLINE);
175 if (reg_error) {
176 char errbuf[1024];
177 regerror(reg_error, &regexp, errbuf, 1024);
178 die("-L parameter '%s': %s", pattern, errbuf);
181 p = find_funcname_matching_regexp(xecfg, (char*) start, &regexp);
182 if (!p)
183 die("-L parameter '%s': no match", pattern);
184 *begin = 0;
185 while (p > nth_line_cb(cb_data, *begin))
186 (*begin)++;
188 if (*begin >= lines)
189 die("-L parameter '%s' matches at EOF", pattern);
191 *end = *begin+1;
192 while (*end < lines) {
193 const char *bol = nth_line_cb(cb_data, *end);
194 const char *eol = nth_line_cb(cb_data, *end+1);
195 if (match_funcname(xecfg, bol, eol))
196 break;
197 (*end)++;
200 regfree(&regexp);
201 free(xecfg);
202 free(pattern);
204 /* compensate for 1-based numbering */
205 (*begin)++;
207 return term;
210 int parse_range_arg(const char *arg, nth_line_fn_t nth_line_cb,
211 void *cb_data, long lines, long *begin, long *end,
212 const char *path)
214 *begin = *end = 0;
216 if (*arg == ':') {
217 arg = parse_range_funcname(arg, nth_line_cb, cb_data, lines, begin, end, path);
218 if (!arg || *arg)
219 return -1;
220 return 0;
223 arg = parse_loc(arg, nth_line_cb, cb_data, lines, 1, begin);
225 if (*arg == ',')
226 arg = parse_loc(arg + 1, nth_line_cb, cb_data, lines, *begin + 1, end);
228 if (*arg)
229 return -1;
231 if (*begin && *end && *end < *begin) {
232 long tmp;
233 tmp = *end; *end = *begin; *begin = tmp;
236 return 0;
239 const char *skip_range_arg(const char *arg)
241 if (*arg == ':')
242 return parse_range_funcname(arg, NULL, NULL, 0, NULL, NULL, NULL);
244 arg = parse_loc(arg, NULL, NULL, 0, -1, NULL);
246 if (*arg == ',')
247 arg = parse_loc(arg+1, NULL, NULL, 0, 0, NULL);
249 return arg;