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, 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 = 0; i < q->nr; i++) {
 116                         struct diff_filepair *p = q->queue[i];
 117                         if (diff_grep(p, &regex, o))
 118                                 goto out; /* do not munge the queue */
 119                 }
 120
 121                 /*
 122                  * Otherwise we will clear the whole queue by copying
 123                  * the empty outq at the end of this function, but
 124                  * first clear the current entries in the queue.
 125                  */
 126                 for (i = 0; i < q->nr; i++)
 127                         diff_free_filepair(q->queue[i]);
 128         } else {
 129                 /* Showing only the filepairs that has the needle */
 130                 for (i = 0; i < q->nr; i++) {
 131                         struct diff_filepair *p = q->queue[i];
 132                         if (diff_grep(p, &regex, o))
 133                                 diff_q(&outq, p);
 134                         else
 135                                 diff_free_filepair(p);
 136                 }
 137         }
 138
 139         free(q->queue);
 140         *q = outq;
 141
 142  out:
 143         regfree(&regex);
 144         return;
 145 }
 146
 147 static unsigned int contains(struct diff_filespec *one, struct diff_options *o,
 148                              regex_t *regexp, kwset_t kws)
 149 {
 150         unsigned int cnt;
 151         unsigned long sz;
 152         const char *data;
 153         if (!o->pickaxe[0])
 154                 return 0;
 155         if (diff_populate_filespec(one, 0))
 156                 return 0;
 157
 158         sz = one->size;
 159         data = one->data;
 160         cnt = 0;
 161
 162         if (regexp) {
 163                 regmatch_t regmatch;
 164                 int flags = 0;
 165
 166                 assert(data[sz] == '\0');
 167                 while (*data && !regexec(regexp, data, 1, &regmatch, flags)) {
 168                         flags |= REG_NOTBOL;
 169                         data += regmatch.rm_eo;
 170                         if (*data && regmatch.rm_so == regmatch.rm_eo)
 171                                 data++;
 172                         cnt++;
 173                 }
 174
 175         } else { /* Classic exact string match */
 176                 while (sz) {
 177                         struct kwsmatch kwsm;
 178                         size_t offset = kwsexec(kws, data, sz, &kwsm);
 179                         const char *found;
 180                         if (offset == -1)
 181                                 break;
 182                         else
 183                                 found = data + offset;
 184                         sz -= found - data + kwsm.size[0];
 185                         data = found + kwsm.size[0];
 186                         cnt++;
 187                 }
 188         }
 189         diff_free_filespec_data(one);
 190         return cnt;
 191 }
 192
 193 static int has_changes(struct diff_filepair *p, struct diff_options *o,
 194                        regex_t *regexp, kwset_t kws)
 195 {
 196         if (!DIFF_FILE_VALID(p->one)) {
 197                 if (!DIFF_FILE_VALID(p->two))
 198                         return 0; /* ignore unmerged */
 199                 /* created */
 200                 return contains(p->two, o, regexp, kws) != 0;
 201         }
 202         if (!DIFF_FILE_VALID(p->two))
 203                 return contains(p->one, o, regexp, kws) != 0;
 204         if (!diff_unmodified_pair(p)) {
 205                 return contains(p->one, o, regexp, kws) !=
 206                        contains(p->two, o, regexp, kws);
 207         }
 208         return 0;
 209 }
 210
 211 static void diffcore_pickaxe_count(struct diff_options *o)
 212 {
 213         const char *needle = o->pickaxe;
 214         int opts = o->pickaxe_opts;
 215         struct diff_queue_struct *q = &diff_queued_diff;
 216         unsigned long len = strlen(needle);
 217         int i;
 218         regex_t regex, *regexp = NULL;
 219         kwset_t kws = NULL;
 220         struct diff_queue_struct outq;
 221         DIFF_QUEUE_CLEAR(&outq);
 222
 223         if (opts & DIFF_PICKAXE_REGEX) {
 224                 int err;
 225                 err = regcomp(&regex, needle, REG_EXTENDED | REG_NEWLINE);
 226                 if (err) {
 227                         /* The POSIX.2 people are surely sick */
 228                         char errbuf[1024];
 229                         regerror(err, &regex, errbuf, 1024);
 230                         regfree(&regex);
 231                         die("invalid pickaxe regex: %s", errbuf);
 232                 }
 233                 regexp = &regex;
 234         } else {
 235                 kws = kwsalloc(NULL);
 236                 kwsincr(kws, needle, len);
 237                 kwsprep(kws);
 238         }
 239
 240         if (opts & DIFF_PICKAXE_ALL) {
 241                 /* Showing the whole changeset if needle exists */
 242                 for (i = 0; i < q->nr; i++) {
 243                         struct diff_filepair *p = q->queue[i];
 244                         if (has_changes(p, o, regexp, kws))
 245                                 goto out; /* do not munge the queue */
 246                 }
 247
 248                 /* otherwise we will clear the whole queue
 249                  * by copying the empty outq at the end of this
 250                  * function, but first clear the current entries
 251                  * in the queue.
 252                  */
 253                 for (i = 0; i < q->nr; i++)
 254                         diff_free_filepair(q->queue[i]);
 255         }
 256         else
 257                 /* Showing only the filepairs that has the needle */
 258                 for (i = 0; i < q->nr; i++) {
 259                         struct diff_filepair *p = q->queue[i];
 260                         if (has_changes(p, o, regexp, kws))
 261                                 diff_q(&outq, p);
 262                         else
 263                                 diff_free_filepair(p);
 264                 }
 265
 266         free(q->queue);
 267         *q = outq;
 268
 269  out:
 270         if (opts & DIFF_PICKAXE_REGEX)
 271                 regfree(&regex);
 272         else
 273                 kwsfree(kws);
 274         return;
 275 }
 276
 277 void diffcore_pickaxe(struct diff_options *o)
 278 {
 279         /* Might want to warn when both S and G are on; I don't care... */
 280         if (o->pickaxe_opts & DIFF_PICKAXE_KIND_G)
 281                 diffcore_pickaxe_grep(o);
 282         else
 283                 diffcore_pickaxe_count(o);
 284 }