LXR busybox/libbb/replace.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Utility routines.
   4 *
   5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6 *
   7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8 */
   9//kbuild:lib-y += replace.o
  10
  11#include "libbb.h"
  12
  13unsigned FAST_FUNC count_strstr(const char *str, const char *sub)
  14{
  15        size_t sub_len = strlen(sub);
  16        unsigned count = 0;
  17
  18        /* If sub is empty, avoid an infinite loop */
  19        if (sub_len == 0)
  20                return strlen(str) + 1;
  21
  22        while ((str = strstr(str, sub)) != NULL) {
  23                count++;
  24                str += sub_len;
  25        }
  26        return count;
  27}
  28
  29char* FAST_FUNC xmalloc_substitute_string(const char *src, int count, const char *sub, const char *repl)
  30{
  31        char *buf, *dst, *end;
  32        size_t sub_len = strlen(sub);
  33        size_t repl_len = strlen(repl);
  34
  35        //dbg_msg("subst(s:'%s',count:%d,sub:'%s',repl:'%s'", src, count, sub, repl);
  36
  37        buf = dst = xmalloc(strlen(src) + count * ((int)repl_len - (int)sub_len) + 1);
  38        /* we replace each sub with repl */
  39        while ((end = strstr(src, sub)) != NULL) {
  40                dst = mempcpy(dst, src, end - src);
  41                dst = mempcpy(dst, repl, repl_len);
  42                /*src = end + 1; - GNU findutils 4.5.10 doesn't do this... */
  43                src = end + sub_len; /* but this. Try "xargs -Iaa echo aaa" */
  44        }
  45        strcpy(dst, src);
  46        //dbg_msg("subst9:'%s'", buf);
  47        return buf;
  48}
  49