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