filehdlr.c

这是有名的＜＜嵌入式系统TCP/IP应用层协议＞＞,M.Tim Jones 著

/*
 *  Embedded HTTP Server Internal Filesystem Utilities
 *
 *  ./software/ch7/emhttps/filehdlr.c
 *
 *  [e-mail]
 *
 */

#include "filehdlr.h"
#include "log.h"

extern unsigned char filedata[];

/*----------------------------------------------------------------------------
 * lookupFilename() - Locate a file in the internal file system
 *--------------------------------------------------------------------------*/
int lookupFilename(char *filename, struct fileHdrStruct *filehdr)
{
  int offset = 0;
  int size;
  int i, found;
  int ret;

  while (filedata[offset] != 0) {

    ret = offset;
    found = 1;

    if ((filedata[offset] == 0xfa) && (filedata[offset+1] == 0xf3)) {

      /* Skip the header */
      offset+=2;

      /* Search the file name, but don't stop if not found... */
      for (i = 0 ; filedata[i+offset] != 0 ; i++) {
        if (filename[i] != filedata[i+offset]) {
          found = 0;
        }
      }

      /* Skip the filename and null terminator */
      offset += (i+1);

      /* Get the file size */
      size = (filedata[offset  ] << 24) | (filedata[offset+1] << 16) |
             (filedata[offset+2] <<  8) | (filedata[offset+3]);

      if (found) {
        filehdr->hdrStart = ret;
        filehdr->size = size;
        filehdr->fileStart = (offset+4);
        emitByte(PREFIX_BYTE); emitByte(NORMAL_REQUEST);
        emitString(filename); emitByte(SUFFIX_BYTE);
        return(1);
      }

      offset += (size+4);
    }

  }
  return(0);
}

/*
 *  Copyright (c) 2002 Charles River Media.  All rights reserved.
 * 
 *  Redistribution and use in source and binary forms, with or 
 *  without modification, is hereby granted without fee 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.
 *    3.  Neither the name of Charles River Media 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 CHARLES RIVER MEDIA AND CONTRIBUTERS 
 * 'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS 
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL CHARLES
 * RIVER MEDIA OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
 * INCIDENTAL, SPECIAL, EXEMPLARAY, 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.
 */