t7003: add test to filter a branch with a commit at epoch
[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 struct diffgrep_cb {
12         regex_t *regexp;
13         int hit;
14 };
15
16 static void diffgrep_consume(void *priv, char *line, unsigned long len)
17 {
18         struct diffgrep_cb *data = priv;
19         regmatch_t regmatch;
20         int hold;
21
22         if (line[0] != '+' && line[0] != '-')
23                 return;
24         if (data->hit)
25                 /*
26                  * NEEDSWORK: we should have a way to terminate the
27                  * caller early.
28                  */
29                 return;
30         /* Yuck -- line ought to be "const char *"! */
31         hold = line[len];
32         line[len] = '\0';
33         data->hit = !regexec(data->regexp, line + 1, 1, &regmatch, 0);
34         line[len] = hold;
35 }
36
37 static void fill_one(struct diff_filespec *one,
38                      mmfile_t *mf, struct userdiff_driver **textconv)
39 {
40         if (DIFF_FILE_VALID(one)) {
41                 *textconv = get_textconv(one);
42                 mf->size = fill_textconv(*textconv, one, &mf->ptr);
43         } else {
44                 memset(mf, 0, sizeof(*mf));
45         }
46 }
47
48 static int diff_grep(struct diff_filepair *p, regex_t *regexp, struct diff_options *o)
49 {
50         regmatch_t regmatch;
51         struct userdiff_driver *textconv_one = NULL;
52         struct userdiff_driver *textconv_two = NULL;
53         mmfile_t mf1, mf2;
54         int hit;
55
56         if (diff_unmodified_pair(p))
57                 return 0;
58
59         fill_one(p->one, &mf1, &textconv_one);
60         fill_one(p->two, &mf2, &textconv_two);
61
62         if (!mf1.ptr) {
63                 if (!mf2.ptr)
64                         return 0; /* ignore unmerged */
65                 /* created "two" -- does it have what we are looking for? */
66                 hit = !regexec(regexp, p->two->data, 1, &regmatch, 0);
67         } else if (!mf2.ptr) {
68                 /* removed "one" -- did it have what we are looking for? */
69                 hit = !regexec(regexp, p->one->data, 1, &regmatch, 0);
70         } else {
71                 /*
72                  * We have both sides; need to run textual diff and see if
73                  * the pattern appears on added/deleted lines.
74                  */
75                 struct diffgrep_cb ecbdata;
76                 xpparam_t xpp;
77                 xdemitconf_t xecfg;
78
79                 memset(&xpp, 0, sizeof(xpp));
80                 memset(&xecfg, 0, sizeof(xecfg));
81                 ecbdata.regexp = regexp;
82                 ecbdata.hit = 0;
83                 xecfg.ctxlen = o->context;
84                 xecfg.interhunkctxlen = o->interhunkcontext;
85                 xdi_diff_outf(&mf1, &mf2, diffgrep_consume, &ecbdata,
86                               &xpp, &xecfg);
87                 hit = ecbdata.hit;
88         }
89         if (textconv_one)
90                 free(mf1.ptr);
91         if (textconv_two)
92                 free(mf2.ptr);
93         return hit;
94 }
95
96 static void diffcore_pickaxe_grep(struct diff_options *o)
97 {
98         struct diff_queue_struct *q = &diff_queued_diff;
99         int i, has_changes, err;
100         regex_t regex;
101         struct diff_queue_struct outq;
102         outq.queue = NULL;
103         outq.nr = outq.alloc = 0;
104
105         err = regcomp(&regex, o->pickaxe, REG_EXTENDED | REG_NEWLINE);
106         if (err) {
107                 char errbuf[1024];
108                 regerror(err, &regex, errbuf, 1024);
109                 regfree(&regex);
110                 die("invalid log-grep regex: %s", errbuf);
111         }
112
113         if (o->pickaxe_opts & DIFF_PICKAXE_ALL) {
114                 /* Showing the whole changeset if needle exists */
115                 for (i = has_changes = 0; !has_changes && i < q->nr; i++) {
116                         struct diff_filepair *p = q->queue[i];
117                         if (diff_grep(p, &regex, o))
118                                 has_changes++;
119                 }
120                 if (has_changes)
121                         return; /* do not munge the queue */
122
123                 /*
124                  * Otherwise we will clear the whole queue by copying
125                  * the empty outq at the end of this function, but
126                  * first clear the current entries in the queue.
127                  */
128                 for (i = 0; i < q->nr; i++)
129                         diff_free_filepair(q->queue[i]);
130         } else {
131                 /* Showing only the filepairs that has the needle */
132                 for (i = 0; i < q->nr; i++) {
133                         struct diff_filepair *p = q->queue[i];
134                         if (diff_grep(p, &regex, o))
135                                 diff_q(&outq, p);
136                         else
137                                 diff_free_filepair(p);
138                 }
139         }
140
141         regfree(&regex);
142
143         free(q->queue);
144         *q = outq;
145         return;
146 }
147
148 static unsigned int contains(struct diff_filespec *one,
149                              const char *needle, unsigned long len,
150                              regex_t *regexp, kwset_t kws)
151 {
152         unsigned int cnt;
153         unsigned long sz;
154         const char *data;
155         if (diff_populate_filespec(one, 0))
156                 return 0;
157         if (!len)
158                 return 0;
159
160         sz = one->size;
161         data = one->data;
162         cnt = 0;
163
164         if (regexp) {
165                 regmatch_t regmatch;
166                 int flags = 0;
167
168                 assert(data[sz] == '\0');
169                 while (*data && !regexec(regexp, data, 1, &regmatch, flags)) {
170                         flags |= REG_NOTBOL;
171                         data += regmatch.rm_eo;
172                         if (*data && regmatch.rm_so == regmatch.rm_eo)
173                                 data++;
174                         cnt++;
175                 }
176
177         } else { /* Classic exact string match */
178                 while (sz) {
179                         size_t offset = kwsexec(kws, data, sz, NULL);
180                         const char *found;
181                         if (offset == -1)
182                                 break;
183                         else
184                                 found = data + offset;
185                         sz -= found - data + len;
186                         data = found + len;
187                         cnt++;
188                 }
189         }
190         diff_free_filespec_data(one);
191         return cnt;
192 }
193
194 static void diffcore_pickaxe_count(struct diff_options *o)
195 {
196         const char *needle = o->pickaxe;
197         int opts = o->pickaxe_opts;
198         struct diff_queue_struct *q = &diff_queued_diff;
199         unsigned long len = strlen(needle);
200         int i, has_changes;
201         regex_t regex, *regexp = NULL;
202         kwset_t kws = NULL;
203         struct diff_queue_struct outq;
204         DIFF_QUEUE_CLEAR(&outq);
205
206         if (opts & DIFF_PICKAXE_REGEX) {
207                 int err;
208                 err = regcomp(&regex, needle, REG_EXTENDED | REG_NEWLINE);
209                 if (err) {
210                         /* The POSIX.2 people are surely sick */
211                         char errbuf[1024];
212                         regerror(err, &regex, errbuf, 1024);
213                         regfree(&regex);
214                         die("invalid pickaxe regex: %s", errbuf);
215                 }
216                 regexp = &regex;
217         } else {
218                 kws = kwsalloc(NULL);
219                 kwsincr(kws, needle, len);
220                 kwsprep(kws);
221         }
222
223         if (opts & DIFF_PICKAXE_ALL) {
224                 /* Showing the whole changeset if needle exists */
225                 for (i = has_changes = 0; !has_changes && i < q->nr; i++) {
226                         struct diff_filepair *p = q->queue[i];
227                         if (!DIFF_FILE_VALID(p->one)) {
228                                 if (!DIFF_FILE_VALID(p->two))
229                                         continue; /* ignore unmerged */
230                                 /* created */
231                                 if (contains(p->two, needle, len, regexp, kws))
232                                         has_changes++;
233                         }
234                         else if (!DIFF_FILE_VALID(p->two)) {
235                                 if (contains(p->one, needle, len, regexp, kws))
236                                         has_changes++;
237                         }
238                         else if (!diff_unmodified_pair(p) &&
239                                  contains(p->one, needle, len, regexp, kws) !=
240                                  contains(p->two, needle, len, regexp, kws))
241                                 has_changes++;
242                 }
243                 if (has_changes)
244                         return; /* not munge the queue */
245
246                 /* otherwise we will clear the whole queue
247                  * by copying the empty outq at the end of this
248                  * function, but first clear the current entries
249                  * in the queue.
250                  */
251                 for (i = 0; i < q->nr; i++)
252                         diff_free_filepair(q->queue[i]);
253         }
254         else
255                 /* Showing only the filepairs that has the needle */
256                 for (i = 0; i < q->nr; i++) {
257                         struct diff_filepair *p = q->queue[i];
258                         has_changes = 0;
259                         if (!DIFF_FILE_VALID(p->one)) {
260                                 if (!DIFF_FILE_VALID(p->two))
261                                         ; /* ignore unmerged */
262                                 /* created */
263                                 else if (contains(p->two, needle, len, regexp,
264                                                   kws))
265                                         has_changes = 1;
266                         }
267                         else if (!DIFF_FILE_VALID(p->two)) {
268                                 if (contains(p->one, needle, len, regexp, kws))
269                                         has_changes = 1;
270                         }
271                         else if (!diff_unmodified_pair(p) &&
272                                  contains(p->one, needle, len, regexp, kws) !=
273                                  contains(p->two, needle, len, regexp, kws))
274                                 has_changes = 1;
275
276                         if (has_changes)
277                                 diff_q(&outq, p);
278                         else
279                                 diff_free_filepair(p);
280                 }
281
282         if (opts & DIFF_PICKAXE_REGEX)
283                 regfree(&regex);
284         else
285                 kwsfree(kws);
286
287         free(q->queue);
288         *q = outq;
289         return;
290 }
291
292 void diffcore_pickaxe(struct diff_options *o)
293 {
294         /* Might want to warn when both S and G are on; I don't care... */
295         if (o->pickaxe_opts & DIFF_PICKAXE_KIND_G)
296                 diffcore_pickaxe_grep(o);
297         else
298                 diffcore_pickaxe_count(o);
299 }