/*
Copyright (c) 2012, Broadcom Europe Ltd
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * 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.
    * Neither the name of the copyright holder nor the
      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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.
*/
 /*****************************************************************************
 * Copyright 2012 Broadcom Corporation.  All rights reserved.
 *
 * This program is the proprietary software of Broadcom Corporation and/or
 * its licensors, and may only be used, duplicated, modified or distributed
 * pursuant to the terms and conditions of a separate, written license
 * agreement executed between you and Broadcom (an "Authorized License").
 * Except as set forth in an Authorized License, Broadcom grants no license
 * (express or implied), right to use, or waiver of any kind with respect to
 * the Software, and Broadcom expressly reserves all rights in and to the
 * Software and all intellectual property rights therein.  IF YOU HAVE NO
 * AUTHORIZED LICENSE, THEN YOU HAVE NO RIGHT TO USE THIS SOFTWARE IN ANY
 * WAY, AND SHOULD IMMEDIATELY NOTIFY BROADCOM AND DISCONTINUE ALL USE OF
 * THE SOFTWARE.
 *
 * Except as expressly set forth in the Authorized License,
 * 1. This program, including its structure, sequence and organization,
 *    constitutes the valuable trade secrets of Broadcom, and you shall use
 *    all reasonable efforts to protect the confidentiality thereof, and to
 *    use this information only in connection with your use of Broadcom
 *    integrated circuit products.
 * 2. TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE SOFTWARE IS PROVIDED "AS IS"
 *    AND WITH ALL FAULTS AND BROADCOM MAKES NO PROMISES, REPRESENTATIONS OR
 *    WARRANTIES, EITHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, WITH
 *    RESPECT TO THE SOFTWARE.  BROADCOM SPECIFICALLY DISCLAIMS ANY AND ALL
 *    IMPLIED WARRANTIES OF TITLE, MERCHANTABILITY, NONINFRINGEMENT, FITNESS
 *    FOR A PARTICULAR PURPOSE, LACK OF VIRUSES, ACCURACY OR COMPLETENESS,
 *    QUIET ENJOYMENT, QUIET POSSESSION OR CORRESPONDENCE TO DESCRIPTION. YOU
 *    ASSUME THE ENTIRE RISK ARISING OUT OF USE OR PERFORMANCE OF THE SOFTWARE.
 * 3. TO THE MAXIMUM EXTENT PERMITTED BY LAW, IN NO EVENT SHALL BROADCOM OR ITS
 *    LICENSORS BE LIABLE FOR (i) CONSEQUENTIAL, INCIDENTAL, SPECIAL, INDIRECT,
 *    OR EXEMPLARY DAMAGES WHATSOEVER ARISING OUT OF OR IN ANY WAY RELATING TO
 *    YOUR USE OF OR INABILITY TO USE THE SOFTWARE EVEN IF BROADCOM HAS BEEN
 *    ADVISED OF THE POSSIBILITY OF SUCH DAMAGES; OR (ii) ANY AMOUNT IN EXCESS
 *    OF THE AMOUNT ACTUALLY PAID FOR THE SOFTWARE ITSELF OR U.S. $1, WHICHEVER
 *    IS GREATER. THESE LIMITATIONS SHALL APPLY NOTWITHSTANDING ANY FAILURE OF
 *    ESSENTIAL PURPOSE OF ANY LIMITED REMEDY.
 *****************************************************************************/

#include "interface/vcos/vcos.h"

#if defined( __KERNEL__ )
#include <linux/string.h>
#include <linux/module.h>
#else
#include <string.h>
#endif

#include <stdarg.h>

/** Like vsnprintf, except it places the output at the specified offset.
  * Output is truncated to fit in buflen bytes, and is guaranteed to be NUL-terminated.
  * Returns the string length before/without truncation.
  */
size_t vcos_safe_vsprintf(char *buf, size_t buflen, size_t offset, const char *fmt, va_list ap)
{
   size_t space = (offset < buflen) ? (buflen - offset) : 0;

   offset += vcos_vsnprintf(buf ? (buf + offset) : NULL, space, fmt, ap);

   return offset;
}

/** Like snprintf, except it places the output at the specified offset.
  * Output is truncated to fit in buflen bytes, and is guaranteed to be NUL-terminated.
  * Returns the string length before/without truncation.
  */
size_t vcos_safe_sprintf(char *buf, size_t buflen, size_t offset, const char *fmt, ...)
{
   size_t space = (offset < buflen) ? (buflen - offset) : 0;
   va_list ap;
   
   va_start(ap, fmt);

   offset += vcos_vsnprintf(buf ? (buf + offset) : NULL, space, fmt, ap);

   va_end(ap);

   return offset;
}

/** Copies string src to dst at the specified offset.
  * Output is truncated to fit in dstlen bytes, i.e. the string is at most
  * (buflen - 1) characters long. Unlike strncpy, exactly one NUL is written
  * to dst, which is always NUL-terminated.
  * Returns the string length before/without truncation.
  */
size_t vcos_safe_strcpy(char *dst, const char *src, size_t dstlen, size_t offset)
{
   if (offset < dstlen)
   {
      const char *p = src;
      char *endp = dst + dstlen -1;

      dst += offset;

      for (; *p!='\0' && dst != endp; dst++, p++)
         *dst = *p;
      *dst = '\0';
   }
   offset += strlen(src);

   return offset;
}