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/* -*- c -*-
* File: loadfile.h
* Author: Igor Vlasenko <vlasenko@imath.kiev.ua>
* Created: Thu Sep 8 17:16:48 2005
*
* $Id$
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef USE_MMAP
#ifdef WIN32
/*
* the win32 code of Viacheslav Sheveliov <slavash@aha.ru>
* viy: should work for win64 too.
*/
#include <windows.h>
#include <stdio.h>
static PSTRING mmap_load_file(const char *filepath) {
PSTRING memarea = { NULL, NULL };
HANDLE hFile, hMapObject = NULL;
hFile = CreateFile(
TEXT(filepath),
GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN,
NULL
);
if (hFile != INVALID_HANDLE_VALUE) {
hMapObject = CreateFileMapping(hFile, NULL, PAGE_READONLY, 0, 0, NULL);
if (hMapObject) {
// Get a pointer to the file-mapped shared memory.
LPCTSTR lpvMem = (LPTSTR) MapViewOfFile(hMapObject, FILE_MAP_READ, 0, 0, 0);
if (lpvMem) {
// Everything OK!
memarea.begin = (char *) lpvMem;
memarea.endnext = memarea.begin + GetFileSize(hFile, NULL);
// After MapViewOfFile we don't need file handles no more.
// Undocumented, but it works! (In read-only mode?)
CloseHandle(hMapObject);
CloseHandle(hFile);
return memarea;
}
}
}
// Something goes wrong
{
// Save last error code, before any system call
DWORD dwLastError = GetLastError();
// Report error, if file size != 0
// Mapping of zero-length file cause CreateFileMapping to fail.
// So skip error messages in this case.
if (hFile == INVALID_HANDLE_VALUE && GetFileSize(hFile, NULL) != 0)
fprintf(stderr, "Could not open file '%s'. (system error#%ld)\n", filepath, dwLastError);
}
// Close all opened handles
if (hMapObject) CloseHandle(hMapObject);
if (hFile != INVALID_HANDLE_VALUE) CloseHandle(hFile);
return memarea;
}
/* we use function, not define, because someday we may need its address */
static int mmap_unload_file(PSTRING memarea) { return UnmapViewOfFile((void*) memarea.begin) ? 0 : -1; };
/* define mmap_unload_file(map) (UnmapViewOfFile((LPCVOID) map.begin) ? 0 : -1) */
#else /* unix, sweet unix :) */
#if defined(HAVE_SYS_MMAN_H) && defined(HAVE_SYS_STAT_H)
/* # define NULL 0 */
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h> /* open */
#include <unistd.h> /* close */
static
PSTRING
mmap_load_file (const char* filepath) {
int fd;
struct stat st;
size_t size_in_bytes;
PSTRING memarea={NULL,NULL};
fd = open(filepath, O_RDONLY);
if (fd == -1) return memarea; /* {NULL,NULL} */
fstat(fd, &st);
size_in_bytes = st.st_size;
/* mmap size_in_bytes+1 to avoid crash with empty file */
memarea.begin = (char *) mmap(0, size_in_bytes+1, PROT_READ, MAP_SHARED, fd, 0);
close(fd);
memarea.endnext=memarea.begin+size_in_bytes;
return memarea;
}
static
int
mmap_unload_file (PSTRING memarea) {
/* destroying */
return munmap((void *)memarea.begin, memarea.endnext-memarea.begin);
}
#endif /* UNIX */
#endif /* WIN32 */
#else
/*
* system seems to have no mmap ;
* we use standard C buffered read
*/
#include <stdio.h>
static
PSTRING
mmap_load_file (const char* filepath) {
FILE *stream;
size_t size_in_bytes=0;
size_t realsize;
size_t chunksize=4096;
size_t memsize=chunksize;
PSTRING memarea={NULL,NULL};
char* writepoint;
/* text mode for HTML::Template compatibility */
stream = fopen(filepath, "r");
if (stream == NULL) return memarea; /* {NULL,NULL} */
/* mmap size_in_bytes+1 to avoid crash with empty file */
memarea.begin=(const char*) malloc(memsize+1);
writepoint=(char*)memarea.begin;
while (1) {
realsize=fread(writepoint, 1, chunksize, stream);
size_in_bytes+=realsize;
if (realsize==chunksize) {
writepoint+=chunksize;
if (size_in_bytes+chunksize>memsize) {
memsize*=2;
memarea.begin=(char*) realloc((char*)memarea.begin, memsize+1);
writepoint=((char*)memarea.begin)+size_in_bytes;
}
} else {
fclose(stream);
memarea.endnext=memarea.begin+size_in_bytes;
return memarea;
}
}
}
static
int
mmap_unload_file (PSTRING memarea) {
/* destroying */
free((char*)memarea.begin);
return 0;
}
#endif /* USE_MMAP */
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