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