Andrew's git - gitweb.git/blob - 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
  11typedef int (*pickaxe_fn)(struct diff_filepair *p, struct diff_options *o, regex_t *regexp, kwset_t kws);
  12
  13static void pickaxe(struct diff_queue_struct *q, struct diff_options *o,
  14                    regex_t *regexp, kwset_t kws, pickaxe_fn fn)
  15{
  16        int i;
  17        struct diff_queue_struct outq;
  18
  19        DIFF_QUEUE_CLEAR(&outq);
  20
  21        if (o->pickaxe_opts & DIFF_PICKAXE_ALL) {
  22                /* Showing the whole changeset if needle exists */
  23                for (i = 0; i < q->nr; i++) {
  24                        struct diff_filepair *p = q->queue[i];
  25                        if (fn(p, o, regexp, kws))
  26                                return; /* do not munge the queue */
  27                }
  28
  29                /*
  30                 * Otherwise we will clear the whole queue by copying
  31                 * the empty outq at the end of this function, but
  32                 * first clear the current entries in the queue.
  33                 */
  34                for (i = 0; i < q->nr; i++)
  35                        diff_free_filepair(q->queue[i]);
  36        } else {
  37                /* Showing only the filepairs that has the needle */
  38                for (i = 0; i < q->nr; i++) {
  39                        struct diff_filepair *p = q->queue[i];
  40                        if (fn(p, o, regexp, kws))
  41                                diff_q(&outq, p);
  42                        else
  43                                diff_free_filepair(p);
  44                }
  45        }
  46
  47        free(q->queue);
  48        *q = outq;
  49}
  50
  51struct diffgrep_cb {
  52        regex_t *regexp;
  53        int hit;
  54};
  55
  56static void diffgrep_consume(void *priv, char *line, unsigned long len)
  57{
  58        struct diffgrep_cb *data = priv;
  59        regmatch_t regmatch;
  60        int hold;
  61
  62        if (line[0] != '+' && line[0] != '-')
  63                return;
  64        if (data->hit)
  65                /*
  66                 * NEEDSWORK: we should have a way to terminate the
  67                 * caller early.
  68                 */
  69                return;
  70        /* Yuck -- line ought to be "const char *"! */
  71        hold = line[len];
  72        line[len] = '\0';
  73        data->hit = !regexec(data->regexp, line + 1, 1, &regmatch, 0);
  74        line[len] = hold;
  75}
  76
  77static void fill_one(struct diff_filespec *one,
  78                     mmfile_t *mf, struct userdiff_driver *textconv)
  79{
  80        if (DIFF_FILE_VALID(one)) {
  81                mf->size = fill_textconv(textconv, one, &mf->ptr);
  82        } else {
  83                memset(mf, 0, sizeof(*mf));
  84        }
  85}
  86
  87static int diff_grep(struct diff_filepair *p, struct diff_options *o,
  88                     regex_t *regexp, kwset_t kws)
  89{
  90        regmatch_t regmatch;
  91        struct userdiff_driver *textconv_one = NULL;
  92        struct userdiff_driver *textconv_two = NULL;
  93        mmfile_t mf1, mf2;
  94        int hit;
  95
  96        if (diff_unmodified_pair(p))
  97                return 0;
  98
  99        textconv_one = get_textconv(p->one);
 100        textconv_two = get_textconv(p->two);
 101
 102        fill_one(p->one, &mf1, textconv_one);
 103        fill_one(p->two, &mf2, textconv_two);
 104
 105        if (!mf1.ptr) {
 106                if (!mf2.ptr)
 107                        return 0; /* ignore unmerged */
 108                /* created "two" -- does it have what we are looking for? */
 109                hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);
 110        } else if (!mf2.ptr) {
 111                /* removed "one" -- did it have what we are looking for? */
 112                hit = !regexec(regexp, mf1.ptr, 1, &regmatch, 0);
 113        } else {
 114                /*
 115                 * We have both sides; need to run textual diff and see if
 116                 * the pattern appears on added/deleted lines.
 117                 */
 118                struct diffgrep_cb ecbdata;
 119                xpparam_t xpp;
 120                xdemitconf_t xecfg;
 121
 122                memset(&xpp, 0, sizeof(xpp));
 123                memset(&xecfg, 0, sizeof(xecfg));
 124                ecbdata.regexp = regexp;
 125                ecbdata.hit = 0;
 126                xecfg.ctxlen = o->context;
 127                xecfg.interhunkctxlen = o->interhunkcontext;
 128                xdi_diff_outf(&mf1, &mf2, diffgrep_consume, &ecbdata,
 129                              &xpp, &xecfg);
 130                hit = ecbdata.hit;
 131        }
 132        if (textconv_one)
 133                free(mf1.ptr);
 134        if (textconv_two)
 135                free(mf2.ptr);
 136        return hit;
 137}
 138
 139static void diffcore_pickaxe_grep(struct diff_options *o)
 140{
 141        int err;
 142        regex_t regex;
 143        int cflags = REG_EXTENDED | REG_NEWLINE;
 144
 145        if (DIFF_OPT_TST(o, PICKAXE_IGNORE_CASE))
 146                cflags |= REG_ICASE;
 147
 148        err = regcomp(&regex, o->pickaxe, cflags);
 149        if (err) {
 150                char errbuf[1024];
 151                regerror(err, &regex, errbuf, 1024);
 152                regfree(&regex);
 153                die("invalid log-grep regex: %s", errbuf);
 154        }
 155
 156        pickaxe(&diff_queued_diff, o, &regex, NULL, diff_grep);
 157
 158        regfree(&regex);
 159        return;
 160}
 161
 162static unsigned int contains(mmfile_t *mf, struct diff_options *o,
 163                             regex_t *regexp, kwset_t kws)
 164{
 165        unsigned int cnt;
 166        unsigned long sz;
 167        const char *data;
 168
 169        sz = mf->size;
 170        data = mf->ptr;
 171        cnt = 0;
 172
 173        if (regexp) {
 174                regmatch_t regmatch;
 175                int flags = 0;
 176
 177                assert(data[sz] == '\0');
 178                while (*data && !regexec(regexp, data, 1, &regmatch, flags)) {
 179                        flags |= REG_NOTBOL;
 180                        data += regmatch.rm_eo;
 181                        if (*data && regmatch.rm_so == regmatch.rm_eo)
 182                                data++;
 183                        cnt++;
 184                }
 185
 186        } else { /* Classic exact string match */
 187                while (sz) {
 188                        struct kwsmatch kwsm;
 189                        size_t offset = kwsexec(kws, data, sz, &kwsm);
 190                        const char *found;
 191                        if (offset == -1)
 192                                break;
 193                        else
 194                                found = data + offset;
 195                        sz -= found - data + kwsm.size[0];
 196                        data = found + kwsm.size[0];
 197                        cnt++;
 198                }
 199        }
 200        return cnt;
 201}
 202
 203static int has_changes(struct diff_filepair *p, struct diff_options *o,
 204                       regex_t *regexp, kwset_t kws)
 205{
 206        struct userdiff_driver *textconv_one = NULL;
 207        struct userdiff_driver *textconv_two = NULL;
 208        mmfile_t mf1, mf2;
 209        int ret;
 210
 211        if (!o->pickaxe[0])
 212                return 0;
 213
 214        textconv_one = get_textconv(p->one);
 215        textconv_two = get_textconv(p->two);
 216
 217        /*
 218         * If we have an unmodified pair, we know that the count will be the
 219         * same and don't even have to load the blobs. Unless textconv is in
 220         * play, _and_ we are using two different textconv filters (e.g.,
 221         * because a pair is an exact rename with different textconv attributes
 222         * for each side, which might generate different content).
 223         */
 224        if (textconv_one == textconv_two && diff_unmodified_pair(p))
 225                return 0;
 226
 227        fill_one(p->one, &mf1, textconv_one);
 228        fill_one(p->two, &mf2, textconv_two);
 229
 230        if (!mf1.ptr) {
 231                if (!mf2.ptr)
 232                        ret = 0; /* ignore unmerged */
 233                /* created */
 234                ret = contains(&mf2, o, regexp, kws) != 0;
 235        }
 236        else if (!mf2.ptr) /* removed */
 237                ret = contains(&mf1, o, regexp, kws) != 0;
 238        else
 239                ret = contains(&mf1, o, regexp, kws) !=
 240                      contains(&mf2, o, regexp, kws);
 241
 242        if (textconv_one)
 243                free(mf1.ptr);
 244        if (textconv_two)
 245                free(mf2.ptr);
 246        diff_free_filespec_data(p->one);
 247        diff_free_filespec_data(p->two);
 248
 249        return ret;
 250}
 251
 252static void diffcore_pickaxe_count(struct diff_options *o)
 253{
 254        const char *needle = o->pickaxe;
 255        int opts = o->pickaxe_opts;
 256        unsigned long len = strlen(needle);
 257        regex_t regex, *regexp = NULL;
 258        kwset_t kws = NULL;
 259
 260        if (opts & DIFF_PICKAXE_REGEX) {
 261                int err;
 262                err = regcomp(&regex, needle, REG_EXTENDED | REG_NEWLINE);
 263                if (err) {
 264                        /* The POSIX.2 people are surely sick */
 265                        char errbuf[1024];
 266                        regerror(err, &regex, errbuf, 1024);
 267                        regfree(&regex);
 268                        die("invalid pickaxe regex: %s", errbuf);
 269                }
 270                regexp = &regex;
 271        } else {
 272                kws = kwsalloc(DIFF_OPT_TST(o, PICKAXE_IGNORE_CASE)
 273                               ? tolower_trans_tbl : NULL);
 274                kwsincr(kws, needle, len);
 275                kwsprep(kws);
 276        }
 277
 278        pickaxe(&diff_queued_diff, o, regexp, kws, has_changes);
 279
 280        if (opts & DIFF_PICKAXE_REGEX)
 281                regfree(&regex);
 282        else
 283                kwsfree(kws);
 284        return;
 285}
 286
 287void diffcore_pickaxe(struct diff_options *o)
 288{
 289        /* Might want to warn when both S and G are on; I don't care... */
 290        if (o->pickaxe_opts & DIFF_PICKAXE_KIND_G)
 291                diffcore_pickaxe_grep(o);
 292        else
 293                diffcore_pickaxe_count(o);
 294}