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#include "my_global.h"
#ifdef UNIX
#include "osutil.h"
#include <errno.h>
#include <stddef.h>
#else /* WINDOWS */
//#include <windows.h>
#include "osutil.h"
#endif /* WINDOWS */
#include <stdlib.h>
#include <stdio.h>
#include "global.h"
#include "plgdbsem.h"
#include "maputil.h"
#ifdef _WIN32
/***********************************************************************/
/* In Insert mode, just open the file for append. Otherwise */
/* create the mapping file object. The map handle can be released */
/* immediately because they will not be used anymore. */
/* If del is true in DELETE mode, then delete the whole file. */
/* Returns the file handle that can be used by caller. */
/***********************************************************************/
HANDLE CreateFileMap(PGLOBAL g, LPCSTR filename,
MEMMAP *mm, MODE mode, bool del)
{
HANDLE hFile;
HANDLE hFileMap;
DWORD access, share, disposition;
memset(mm, 0, sizeof(MEMMAP));
*g->Message = '\0';
switch (mode) {
case MODE_READ:
access = GENERIC_READ;
share = FILE_SHARE_READ;
disposition = OPEN_EXISTING;
break;
case MODE_UPDATE:
case MODE_DELETE:
access = GENERIC_READ | GENERIC_WRITE;
share = 0;
disposition = (del) ? TRUNCATE_EXISTING : OPEN_EXISTING;
break;
case MODE_INSERT:
access = GENERIC_WRITE;
share = 0;
disposition = OPEN_ALWAYS;
break;
default:
snprintf(g->Message, sizeof(g->Message), MSG(BAD_FUNC_MODE), "CreateFileMap", mode);
return INVALID_HANDLE_VALUE;
} // endswitch
hFile = CreateFile(filename, access, share, NULL, disposition,
FILE_ATTRIBUTE_NORMAL, NULL);
if (hFile != INVALID_HANDLE_VALUE)
if (mode != MODE_INSERT) {
/*****************************************************************/
/* Create the file-mapping object. */
/*****************************************************************/
access = (mode == MODE_READ) ? PAGE_READONLY : PAGE_READWRITE;
hFileMap = CreateFileMapping(hFile, NULL, access, 0, 0, NULL);
if (!hFileMap) {
DWORD ler = GetLastError();
if (ler && ler != 1006) {
snprintf(g->Message, sizeof(g->Message), MSG(FILE_MAP_ERROR), filename, ler);
CloseHandle(hFile);
return INVALID_HANDLE_VALUE;
} else {
snprintf(g->Message, sizeof(g->Message), MSG(FILE_IS_EMPTY), filename);
return hFile;
} // endif ler
} // endif hFileMap
access = (mode == MODE_READ) ? FILE_MAP_READ : FILE_MAP_WRITE;
if (!(mm->memory = MapViewOfFile(hFileMap, access, 0, 0, 0))) {
DWORD ler = GetLastError();
snprintf(g->Message, sizeof(g->Message), "Error %ld in MapViewOfFile %s",
ler, filename);
CloseHandle(hFile);
return INVALID_HANDLE_VALUE;
} // endif memory
// lenH is the high-order word of the file size
mm->lenL = GetFileSize(hFile, &mm->lenH);
CloseHandle(hFileMap); // Not used anymore
} else // MODE_INSERT
/*****************************************************************/
/* The starting point must be the end of file as for append. */
/*****************************************************************/
SetFilePointer(hFile, 0, NULL, FILE_END);
return hFile;
} // end of CreateFileMap
bool CloseMemMap(LPVOID memory, size_t dwSize)
{
return (memory) ? !UnmapViewOfFile(memory) : false;
} // end of CloseMemMap
#else /* UNIX */
// Code to handle Linux and Solaris
#include <sys/types.h>
#include <sys/mman.h>
#include <unistd.h>
#include <sys/stat.h>
#include <fcntl.h>
/***********************************************************************/
/* In Insert mode, just open the file for append. Otherwise */
/* create the mapping file object. The map handle can be released */
/* immediately because they will not be used anymore. */
/* If del is true in DELETE mode, then delete the whole file. */
/* Returns the file handle that can be used by caller. */
/***********************************************************************/
HANDLE CreateFileMap(PGLOBAL g, LPCSTR fileName,
MEMMAP *mm, MODE mode, bool del)
{
unsigned int openMode;
int protmode;
HANDLE fd;
size_t filesize;
struct stat st;
memset(mm, 0, sizeof(MEMMAP));
*g->Message = '\0';
switch (mode) {
case MODE_READ:
openMode = O_RDONLY;
protmode = PROT_READ;
break;
case MODE_UPDATE:
case MODE_DELETE:
openMode = (del) ? (O_RDWR | O_TRUNC) : O_RDWR;
protmode = PROT_READ | PROT_WRITE;
break;
case MODE_INSERT:
openMode = (O_WRONLY | O_CREAT | O_APPEND);
protmode = PROT_WRITE;
break;
default:
snprintf(g->Message, sizeof(g->Message), MSG(BAD_FUNC_MODE), "CreateFileMap", mode);
return INVALID_HANDLE_VALUE;
} // endswitch
// Try to open the addressed file.
fd= global_open(g, MSGID_NONE, fileName, openMode);
if (fd != INVALID_HANDLE_VALUE && mode != MODE_INSERT) {
/* We must know about the size of the file. */
if (fstat(fd, &st)) {
snprintf(g->Message, sizeof(g->Message), MSG(FILE_MAP_ERROR), fileName, errno);
close(fd);
return INVALID_HANDLE_VALUE;
} // endif fstat
if ((filesize = st.st_size))
// Now we are ready to load the file. If mmap() is available we try
// this first. If not available or it failed we try to load it.
mm->memory = mmap(NULL, filesize, protmode, MAP_SHARED, fd, 0);
else
mm->memory = 0;
if (mm->memory != MAP_FAILED) {
mm->lenL = (mm->memory != 0) ? filesize : 0;
mm->lenH = 0;
} else {
strcpy(g->Message, "Memory mapping failed");
close(fd);
return INVALID_HANDLE_VALUE;
} // endif memory
} /* endif fd */
// mmap() call was successful. ??????????
return fd;
} // end of CreateFileMap
bool CloseMemMap(void *memory, size_t dwSize)
{
if (memory) {
// All this must be redesigned
msync((char*)memory, dwSize, MS_SYNC);
return (munmap((char*)memory, dwSize) < 0) ? true : false;
} else
return false;
} // end of CloseMemMap
#endif // UNIX
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