libs/libc/regex/regerror.c

/****************************************************************************
 * libs/libc/regex/regerror.c
 *
 * regerror.c - TRE POSIX compatible matching functions (and more).
 *
 *  Copyright (c) 2001-2009 Ville Laurikari <vl@iki.fi>
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS
 *  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *  A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
 *  HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <string.h>
#include <regex.h>
#include <stdio.h>

/* Error message strings for error codes listed in `regex.h'.  This list
 * needs to be in sync with the codes listed there, naturally.
 */

/* Converted to single string by Rich Felker to remove the need for
 * data relocations at runtime, 27 Feb 2006.
 */

/****************************************************************************
 * Private Data
 ****************************************************************************/

static const char messages[] =
{
  "No error\0"
  "No match\0"
  "Invalid regexp\0"
  "Unknown collating element\0"
  "Unknown character class name\0"
  "Trailing backslash\0"
  "Invalid back reference\0"
  "Missing ']'\0"
  "Missing ')'\0"
  "Missing '}'\0"
  "Invalid contents of {}\0"
  "Invalid character range\0"
  "Out of memory\0"
  "Repetition not preceded by valid expression\0"
  "\0Unknown error"
};

/****************************************************************************
 * Public Functions
 ****************************************************************************/

size_t regerror(int e, const regex_t *restrict preg, char *restrict buf,
                size_t size)
{
  const char *s;

  for (s = messages; e && *s; e--, s += strlen(s) + 1)
    {
    }

  if (!*s)
    {
      s++;
    }

  return 1 + snprintf(buf, size, "%s", s);
}