/****************************************************************************
* binfmt/libnxflat/libnxflat_read.c
*
* Copyright (C) 2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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.
* 3. Neither the name NuttX 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 OWNER 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 <nuttx/config.h>
#include <sys/types.h>
#include <unistd.h>
#include <string.h>
#include <nxflat.h>
#include <debug.h>
#include <errno.h>
#include <arpa/inet.h>
#include <nuttx/nxflat.h>
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/****************************************************************************
* Private Constant Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxflat_read
*
* Description:
* Read 'readsize' bytes from the object file at 'offset'
*
* Returned Value:
* 0 (OK) is returned on success and a negated errno is returned on
* failure.
*
****************************************************************************/
int nxflat_read(struct nxflat_loadinfo_s *loadinfo, char *buffer, int readsize, int offset)
{
ssize_t nbytes; /* Number of bytes read */
off_t rpos; /* Position returned by lseek */
char *bufptr; /* Next buffer location to read into */
int bytesleft; /* Number of bytes of .data left to read */
int bytesread; /* Total number of bytes read */
/* Seek to the position in the object file where the initialized
* data is saved.
*/
bytesread = 0;
bufptr = buffer;
bytesleft = readsize;
do
{
rpos = lseek(loadinfo->filfd, offset, SEEK_SET);
if (rpos != offset)
{
bdbg("Failed to seek to position %d: %d\n", offset, errno);
return -errno;
}
/* Read the file data at offset into the user buffer */
nbytes = read(loadinfo->filfd, bufptr, bytesleft);
if (nbytes < 0)
{
if (errno != EINTR)
{
bdbg("Read of .data failed: %d\n", errno);
return -errno;
}
}
else if (nbytes == 0)
{
bdbg("Unexpected end of file\n");
return -ENODATA;
}
else
{
bytesread += nbytes;
bytesleft -= nbytes;
bufptr += nbytes;
offset += nbytes;
}
}
while (bytesread < readsize);
return OK;
}
