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/* ----------------------------------------------------------------------- *
*
* Copyright 2008 rPath, Inc. - All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston MA 02110-1301, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* mapfile.c
*
* Memory-map a file, and/or read it into a memory buffer.
* If the "writable" flag is set, return a writable memory
* buffer, *not* one which writes back to the file!
*
* Note: if this is modified to use a buffer, always round the buffer
* size up to at least a dword boundary.
*/
#include "wraplinux.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
void *mapfile(int fd, size_t *len, bool writable)
{
struct stat st;
void *ptr;
int prot, flags;
if (fstat(fd, &st))
return NULL;
*len = st.st_size;
if (writable) {
prot = PROT_READ|PROT_WRITE;
flags = MAP_PRIVATE;
} else {
prot = PROT_READ;
flags = MAP_SHARED;
}
ptr = mmap(NULL, st.st_size, prot, flags, fd, 0);
return (ptr == MAP_FAILED) ? NULL : ptr;
}
void unmapfile(int fd, void *ptr, size_t len)
{
if (ptr)
munmap(ptr, len);
if (fd >= 0)
close(fd);
}
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