diffcore-pickaxe: simplify has_changes and contains
[git/git.git] / diffcore-pickaxe.c
1 /*
2 * Copyright (C) 2005 Junio C Hamano
3 * Copyright (C) 2010 Google Inc.
4 */
5 #include "cache.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "xdiff-interface.h"
9 #include "kwset.h"
10
11 typedef int (*pickaxe_fn)(mmfile_t *one, mmfile_t *two,
12 struct diff_options *o,
13 regex_t *regexp, kwset_t kws);
14
15 static int pickaxe_match(struct diff_filepair *p, struct diff_options *o,
16 regex_t *regexp, kwset_t kws, pickaxe_fn fn);
17
18 static void pickaxe(struct diff_queue_struct *q, struct diff_options *o,
19 regex_t *regexp, kwset_t kws, pickaxe_fn fn)
20 {
21 int i;
22 struct diff_queue_struct outq;
23
24 DIFF_QUEUE_CLEAR(&outq);
25
26 if (o->pickaxe_opts & DIFF_PICKAXE_ALL) {
27 /* Showing the whole changeset if needle exists */
28 for (i = 0; i < q->nr; i++) {
29 struct diff_filepair *p = q->queue[i];
30 if (pickaxe_match(p, o, regexp, kws, fn))
31 return; /* do not munge the queue */
32 }
33
34 /*
35 * Otherwise we will clear the whole queue by copying
36 * the empty outq at the end of this function, but
37 * first clear the current entries in the queue.
38 */
39 for (i = 0; i < q->nr; i++)
40 diff_free_filepair(q->queue[i]);
41 } else {
42 /* Showing only the filepairs that has the needle */
43 for (i = 0; i < q->nr; i++) {
44 struct diff_filepair *p = q->queue[i];
45 if (pickaxe_match(p, o, regexp, kws, fn))
46 diff_q(&outq, p);
47 else
48 diff_free_filepair(p);
49 }
50 }
51
52 free(q->queue);
53 *q = outq;
54 }
55
56 struct diffgrep_cb {
57 regex_t *regexp;
58 int hit;
59 };
60
61 static void diffgrep_consume(void *priv, char *line, unsigned long len)
62 {
63 struct diffgrep_cb *data = priv;
64 regmatch_t regmatch;
65 int hold;
66
67 if (line[0] != '+' && line[0] != '-')
68 return;
69 if (data->hit)
70 /*
71 * NEEDSWORK: we should have a way to terminate the
72 * caller early.
73 */
74 return;
75 /* Yuck -- line ought to be "const char *"! */
76 hold = line[len];
77 line[len] = '\0';
78 data->hit = !regexec(data->regexp, line + 1, 1, &regmatch, 0);
79 line[len] = hold;
80 }
81
82 static int diff_grep(mmfile_t *one, mmfile_t *two,
83 struct diff_options *o,
84 regex_t *regexp, kwset_t kws)
85 {
86 regmatch_t regmatch;
87 struct diffgrep_cb ecbdata;
88 xpparam_t xpp;
89 xdemitconf_t xecfg;
90
91 if (!one)
92 return !regexec(regexp, two->ptr, 1, &regmatch, 0);
93 if (!two)
94 return !regexec(regexp, one->ptr, 1, &regmatch, 0);
95
96 /*
97 * We have both sides; need to run textual diff and see if
98 * the pattern appears on added/deleted lines.
99 */
100 memset(&xpp, 0, sizeof(xpp));
101 memset(&xecfg, 0, sizeof(xecfg));
102 ecbdata.regexp = regexp;
103 ecbdata.hit = 0;
104 xecfg.ctxlen = o->context;
105 xecfg.interhunkctxlen = o->interhunkcontext;
106 xdi_diff_outf(one, two, diffgrep_consume, &ecbdata,
107 &xpp, &xecfg);
108 return ecbdata.hit;
109 }
110
111 static void diffcore_pickaxe_grep(struct diff_options *o)
112 {
113 int err;
114 regex_t regex;
115 int cflags = REG_EXTENDED | REG_NEWLINE;
116
117 if (DIFF_OPT_TST(o, PICKAXE_IGNORE_CASE))
118 cflags |= REG_ICASE;
119
120 err = regcomp(&regex, o->pickaxe, cflags);
121 if (err) {
122 char errbuf[1024];
123 regerror(err, &regex, errbuf, 1024);
124 regfree(&regex);
125 die("invalid log-grep regex: %s", errbuf);
126 }
127
128 pickaxe(&diff_queued_diff, o, &regex, NULL, diff_grep);
129
130 regfree(&regex);
131 return;
132 }
133
134 static unsigned int contains(mmfile_t *mf, regex_t *regexp, kwset_t kws)
135 {
136 unsigned int cnt;
137 unsigned long sz;
138 const char *data;
139
140 sz = mf->size;
141 data = mf->ptr;
142 cnt = 0;
143
144 if (regexp) {
145 regmatch_t regmatch;
146 int flags = 0;
147
148 assert(data[sz] == '\0');
149 while (*data && !regexec(regexp, data, 1, &regmatch, flags)) {
150 flags |= REG_NOTBOL;
151 data += regmatch.rm_eo;
152 if (*data && regmatch.rm_so == regmatch.rm_eo)
153 data++;
154 cnt++;
155 }
156
157 } else { /* Classic exact string match */
158 while (sz) {
159 struct kwsmatch kwsm;
160 size_t offset = kwsexec(kws, data, sz, &kwsm);
161 const char *found;
162 if (offset == -1)
163 break;
164 else
165 found = data + offset;
166 sz -= found - data + kwsm.size[0];
167 data = found + kwsm.size[0];
168 cnt++;
169 }
170 }
171 return cnt;
172 }
173
174 static int has_changes(mmfile_t *one, mmfile_t *two,
175 struct diff_options *o,
176 regex_t *regexp, kwset_t kws)
177 {
178 unsigned int one_contains = one ? contains(one, regexp, kws) : 0;
179 unsigned int two_contains = two ? contains(two, regexp, kws) : 0;
180 return one_contains != two_contains;
181 }
182
183 static int pickaxe_match(struct diff_filepair *p, struct diff_options *o,
184 regex_t *regexp, kwset_t kws, pickaxe_fn fn)
185 {
186 struct userdiff_driver *textconv_one = NULL;
187 struct userdiff_driver *textconv_two = NULL;
188 mmfile_t mf1, mf2;
189 int ret;
190
191 if (!o->pickaxe[0])
192 return 0;
193
194 /* ignore unmerged */
195 if (!DIFF_FILE_VALID(p->one) && !DIFF_FILE_VALID(p->two))
196 return 0;
197
198 if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
199 textconv_one = get_textconv(p->one);
200 textconv_two = get_textconv(p->two);
201 }
202
203 /*
204 * If we have an unmodified pair, we know that the count will be the
205 * same and don't even have to load the blobs. Unless textconv is in
206 * play, _and_ we are using two different textconv filters (e.g.,
207 * because a pair is an exact rename with different textconv attributes
208 * for each side, which might generate different content).
209 */
210 if (textconv_one == textconv_two && diff_unmodified_pair(p))
211 return 0;
212
213 mf1.size = fill_textconv(textconv_one, p->one, &mf1.ptr);
214 mf2.size = fill_textconv(textconv_two, p->two, &mf2.ptr);
215
216 ret = fn(DIFF_FILE_VALID(p->one) ? &mf1 : NULL,
217 DIFF_FILE_VALID(p->two) ? &mf2 : NULL,
218 o, regexp, kws);
219
220 if (textconv_one)
221 free(mf1.ptr);
222 if (textconv_two)
223 free(mf2.ptr);
224 diff_free_filespec_data(p->one);
225 diff_free_filespec_data(p->two);
226
227 return ret;
228 }
229
230 static void diffcore_pickaxe_count(struct diff_options *o)
231 {
232 const char *needle = o->pickaxe;
233 int opts = o->pickaxe_opts;
234 unsigned long len = strlen(needle);
235 regex_t regex, *regexp = NULL;
236 kwset_t kws = NULL;
237
238 if (opts & DIFF_PICKAXE_REGEX) {
239 int err;
240 err = regcomp(&regex, needle, REG_EXTENDED | REG_NEWLINE);
241 if (err) {
242 /* The POSIX.2 people are surely sick */
243 char errbuf[1024];
244 regerror(err, &regex, errbuf, 1024);
245 regfree(&regex);
246 die("invalid pickaxe regex: %s", errbuf);
247 }
248 regexp = &regex;
249 } else {
250 kws = kwsalloc(DIFF_OPT_TST(o, PICKAXE_IGNORE_CASE)
251 ? tolower_trans_tbl : NULL);
252 kwsincr(kws, needle, len);
253 kwsprep(kws);
254 }
255
256 pickaxe(&diff_queued_diff, o, regexp, kws, has_changes);
257
258 if (opts & DIFF_PICKAXE_REGEX)
259 regfree(&regex);
260 else
261 kwsfree(kws);
262 return;
263 }
264
265 void diffcore_pickaxe(struct diff_options *o)
266 {
267 /* Might want to warn when both S and G are on; I don't care... */
268 if (o->pickaxe_opts & DIFF_PICKAXE_KIND_G)
269 diffcore_pickaxe_grep(o);
270 else
271 diffcore_pickaxe_count(o);
272 }