Andrew's git - gitweb.git/blob - diffcore-pickaxe.c

   1/*
   2 * Copyright (C) 2005 Junio C Hamano
   3 */
   4#include "cache.h"
   5#include "diff.h"
   6#include "diffcore.h"
   7
   8static unsigned int contains(struct diff_filespec *one,
   9                             const char *needle, unsigned long len,
  10                             regex_t *regexp)
  11{
  12        unsigned int cnt;
  13        unsigned long offset, sz;
  14        const char *data;
  15        if (diff_populate_filespec(one, 0))
  16                return 0;
  17        if (!len)
  18                return 0;
  19
  20        sz = one->size;
  21        data = one->data;
  22        cnt = 0;
  23
  24        if (regexp) {
  25                regmatch_t regmatch;
  26                int flags = 0;
  27
  28                while (*data && !regexec(regexp, data, 1, &regmatch, flags)) {
  29                        flags |= REG_NOTBOL;
  30                        data += regmatch.rm_so;
  31                        if (*data) data++;
  32                        cnt++;
  33                }
  34
  35        } else { /* Classic exact string match */
  36                /* Yes, I've heard of strstr(), but the thing is *data may
  37                 * not be NUL terminated.  Sue me.
  38                 */
  39                for (offset = 0; offset + len <= sz; offset++) {
  40                        /* we count non-overlapping occurrences of needle */
  41                        if (!memcmp(needle, data + offset, len)) {
  42                                offset += len - 1;
  43                                cnt++;
  44                        }
  45                }
  46        }
  47        diff_free_filespec_data(one);
  48        return cnt;
  49}
  50
  51void diffcore_pickaxe(const char *needle, int opts)
  52{
  53        struct diff_queue_struct *q = &diff_queued_diff;
  54        unsigned long len = strlen(needle);
  55        int i, has_changes;
  56        regex_t regex, *regexp = NULL;
  57        struct diff_queue_struct outq;
  58        outq.queue = NULL;
  59        outq.nr = outq.alloc = 0;
  60
  61        if (opts & DIFF_PICKAXE_REGEX) {
  62                int err;
  63                err = regcomp(&regex, needle, REG_EXTENDED | REG_NEWLINE);
  64                if (err) {
  65                        /* The POSIX.2 people are surely sick */
  66                        char errbuf[1024];
  67                        regerror(err, &regex, errbuf, 1024);
  68                        regfree(&regex);
  69                        die("invalid pickaxe regex: %s", errbuf);
  70                }
  71                regexp = &regex;
  72        }
  73
  74        if (opts & DIFF_PICKAXE_ALL) {
  75                /* Showing the whole changeset if needle exists */
  76                for (i = has_changes = 0; !has_changes && i < q->nr; i++) {
  77                        struct diff_filepair *p = q->queue[i];
  78                        if (!DIFF_FILE_VALID(p->one)) {
  79                                if (!DIFF_FILE_VALID(p->two))
  80                                        continue; /* ignore unmerged */
  81                                /* created */
  82                                if (contains(p->two, needle, len, regexp))
  83                                        has_changes++;
  84                        }
  85                        else if (!DIFF_FILE_VALID(p->two)) {
  86                                if (contains(p->one, needle, len, regexp))
  87                                        has_changes++;
  88                        }
  89                        else if (!diff_unmodified_pair(p) &&
  90                                 contains(p->one, needle, len, regexp) !=
  91                                 contains(p->two, needle, len, regexp))
  92                                has_changes++;
  93                }
  94                if (has_changes)
  95                        return; /* not munge the queue */
  96
  97                /* otherwise we will clear the whole queue
  98                 * by copying the empty outq at the end of this
  99                 * function, but first clear the current entries
 100                 * in the queue.
 101                 */
 102                for (i = 0; i < q->nr; i++)
 103                        diff_free_filepair(q->queue[i]);
 104        }
 105        else
 106                /* Showing only the filepairs that has the needle */
 107                for (i = 0; i < q->nr; i++) {
 108                        struct diff_filepair *p = q->queue[i];
 109                        has_changes = 0;
 110                        if (!DIFF_FILE_VALID(p->one)) {
 111                                if (!DIFF_FILE_VALID(p->two))
 112                                        ; /* ignore unmerged */
 113                                /* created */
 114                                else if (contains(p->two, needle, len, regexp))
 115                                        has_changes = 1;
 116                        }
 117                        else if (!DIFF_FILE_VALID(p->two)) {
 118                                if (contains(p->one, needle, len, regexp))
 119                                        has_changes = 1;
 120                        }
 121                        else if (!diff_unmodified_pair(p) &&
 122                                 contains(p->one, needle, len, regexp) !=
 123                                 contains(p->two, needle, len, regexp))
 124                                has_changes = 1;
 125
 126                        if (has_changes)
 127                                diff_q(&outq, p);
 128                        else
 129                                diff_free_filepair(p);
 130                }
 131
 132        if (opts & DIFF_PICKAXE_REGEX) {
 133                regfree(&regex);
 134        }
 135
 136        free(q->queue);
 137        *q = outq;
 138        return;
 139}