phobos/std/mmfile.d
2007-09-10 04:09:37 +00:00

410 lines
8.1 KiB
D

// Copyright (c) 2004 by Digital Mars
// All Rights Reserved
// written by Walter Bright and Matthew Wilson (Sysesis Software Pty Ltd.)
// www.digitalmars.com
// www.synesis.com.au/software
/*
* Memory mapped files.
*/
module mmfile;
private import std.file;
private import std.c.stdio;
private import std.c.stdlib;
private import std.path;
private import std.string;
//debug = MMFILE;
version (Win32)
{
private import std.c.windows.windows;
private import std.utf;
private int useWfuncs = 1;
private uint dwVersion;
static this()
{ // http://msdn.microsoft.com/library/default.asp?url=/library/en-us/sysinfo/base/getversion.asp
dwVersion = GetVersion();
// Win 95, 98, ME do not implement the W functions
useWfuncs = (dwVersion < 0x80000000);
}
}
else version (linux)
{
private import std.c.linux.linux;
}
else
{
static assert(0);
}
auto class MmFile
{
enum Mode
{ Read, // read existing file
ReadWriteNew, // delete existing file, write new file
ReadWrite, // read/write existing file, create if not existing
ReadCopyOnWrite, // read/write existing file, copy on write
}
/* Open for reading
*/
this(char[] filename)
{
this(filename, Mode.Read, 0, null);
}
/* Open
*/
this(char[] filename, Mode mode, size_t size, void* address)
{
this.filename = filename;
version (Win32)
{
void* p;
uint dwDesiredAccess2;
uint dwShareMode;
uint dwCreationDisposition;
uint dwDesiredAccess;
uint flProtect;
if (dwVersion & 0x80000000 && (dwVersion & 0xFF) == 3)
{
throw new FileException(filename,
"Win32s does not implement mm files");
}
switch (mode)
{
case Mode.Read:
dwDesiredAccess2 = GENERIC_READ;
dwShareMode = FILE_SHARE_READ;
dwCreationDisposition = OPEN_EXISTING;
flProtect = PAGE_READONLY;
dwDesiredAccess = FILE_MAP_READ;
break;
case Mode.ReadWriteNew:
assert(size != 0);
dwDesiredAccess2 = GENERIC_READ | GENERIC_WRITE;
dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
dwCreationDisposition = CREATE_ALWAYS;
flProtect = PAGE_READWRITE;
dwDesiredAccess = FILE_MAP_WRITE;
break;
case Mode.ReadWrite:
dwDesiredAccess2 = GENERIC_READ | GENERIC_WRITE;
dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
dwCreationDisposition = OPEN_ALWAYS;
flProtect = PAGE_READWRITE;
dwDesiredAccess = FILE_MAP_WRITE;
break;
case Mode.ReadCopyOnWrite:
if (dwVersion & 0x80000000)
{
throw new FileException(filename,
"Win9x does not implement copy on write");
}
dwDesiredAccess2 = GENERIC_READ | GENERIC_WRITE;
dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
dwCreationDisposition = OPEN_EXISTING;
flProtect = PAGE_WRITECOPY;
dwDesiredAccess = FILE_MAP_COPY;
break;
}
if (useWfuncs)
{
wchar* namez = std.utf.toUTF16z(filename);
hFile = CreateFileW(namez,
dwDesiredAccess2,
dwShareMode,
null,
dwCreationDisposition,
FILE_ATTRIBUTE_NORMAL,
cast(HANDLE)null);
}
else
{
char* namez = std.file.toMBSz(filename);
hFile = CreateFileA(namez,
dwDesiredAccess2,
dwShareMode,
null,
dwCreationDisposition,
FILE_ATTRIBUTE_NORMAL,
cast(HANDLE)null);
}
if (hFile == INVALID_HANDLE_VALUE)
goto err1;
hFileMap = CreateFileMappingA(hFile, null, flProtect, 0, size, null);
if (hFileMap == null) // mapping failed
goto err1;
p = MapViewOfFileEx(hFileMap, dwDesiredAccess, 0, 0, size, address);
if (p == null) // mapping view failed
{
goto err1;
}
if (size == 0)
size = GetFileSize(hFile, null);
debug (MMFILE) printf("MmFile.this(): p = %p, size = %d\n", p, size);
data = p[0 .. size];
return;
err1:
if (hFileMap != null)
CloseHandle(hFileMap);
hFileMap = null;
if (hFile != INVALID_HANDLE_VALUE)
CloseHandle(hFile);
hFile = INVALID_HANDLE_VALUE;
errNo();
}
else version (linux)
{
char* namez = toStringz(filename);
void* p;
int fd;
int prot;
int flags;
int oflag;
int fmode;
switch (mode)
{
case Mode.Read:
flags = MAP_SHARED;
prot = PROT_READ;
oflag = O_RDONLY;
fmode = 0;
break;
case Mode.ReadWriteNew:
assert(size != 0);
flags = MAP_SHARED;
prot = PROT_READ | PROT_WRITE;
oflag = O_CREAT | O_RDWR | O_TRUNC;
fmode = 0660;
break;
case Mode.ReadWrite:
flags = MAP_SHARED;
prot = PROT_READ | PROT_WRITE;
oflag = O_CREAT | O_RDWR;
fmode = 0660;
break;
case Mode.ReadCopyOnWrite:
flags = MAP_PRIVATE;
prot = PROT_READ | PROT_WRITE;
oflag = O_RDWR;
fmode = 0;
break;
}
if (filename.length)
{
struct_stat statbuf;
fd = std.c.linux.linux.open(namez, oflag, fmode);
if (fd == -1)
{
printf("\topen error, errno = %d\n",getErrno());
errNo();
}
if (std.c.linux.linux.fstat(fd, &statbuf))
{
//printf("\tfstat error, errno = %d\n",getErrno());
std.c.linux.linux.close(fd);
errNo();
}
if (prot & PROT_WRITE && size > statbuf.st_size)
{
// Need to make the file size bytes big
std.c.linux.linux.lseek(fd, size - 1, SEEK_SET);
char c = 0;
std.c.linux.linux.write(fd, &c, 1);
}
else if (prot & PROT_READ && size == 0)
size = statbuf.st_size;
}
else
{
fd = -1;
flags |= MAP_ANONYMOUS;
}
p = mmap(address, size, prot, flags, fd, 0);
//printf(" p = %x, size = %d\n", p, size);
/* Memory mapping stays active even if we close the handle.
* Closing it now avoids worrys about closing it during error
* recovery.
*/
if (fd != -1 && std.c.linux.linux.close(fd) == -1)
errNo();
if (p == MAP_FAILED) // in sys/mman.h
errNo();
data = p[0 .. size];
}
else
{
static assert(0);
}
}
~this()
{
debug (MMFILE) printf("MmFile.~this()\n");
version (Win32)
{
/* Note that under Windows 95, UnmapViewOfFile() seems to return
* random values, not TRUE or FALSE.
*/
if (data && UnmapViewOfFile(data) == FALSE &&
(dwVersion & 0x80000000) == 0)
errNo();
data = null;
if (hFileMap != null && CloseHandle(hFileMap) != TRUE)
errNo();
hFileMap = null;
if (hFile != INVALID_HANDLE_VALUE && CloseHandle(hFile) != TRUE)
errNo();
hFile = INVALID_HANDLE_VALUE;
}
else version (linux)
{
int i;
i = munmap(cast(void*)data, data.length);
if (i != 0)
errNo();
}
else
{
static assert(0);
}
data = null;
}
/* Flush any pending output.
*/
void flush()
{
debug (MMFILE) printf("MmFile.flush()\n");
version (Win32)
{
FlushViewOfFile(data, data.length);
}
else version (linux)
{
int i;
i = msync(cast(void*)data, data.length, MS_SYNC); // sys/mman.h
if (i != 0)
errNo();
}
else
{
static assert(0);
}
}
size_t length()
{
debug (MMFILE) printf("MmFile.length()\n");
return data.length;
}
void[] opSlice()
{
debug (MMFILE) printf("MmFile.opSlice()\n");
return data;
}
void[] opSlice(size_t i1, size_t i2)
{
debug (MMFILE) printf("MmFile.opSlice(%d, %d)\n", i1, i2);
return data[i1 .. i2];
}
ubyte opIndex(size_t i)
{
debug (MMFILE) printf("MmFile.opIndex(%d)\n", i);
return (cast(ubyte[])data)[i];
}
ubyte opIndex(size_t i, ubyte value)
{
debug (MMFILE) printf("MmFile.opIndex(%d, %d)\n", i, value);
return (cast(ubyte[])data)[i] = value;
}
private:
char[] filename;
void[] data;
version (Win32)
{
HANDLE hFile = INVALID_HANDLE_VALUE;
HANDLE hFileMap = null;
}
else version (linux)
{
}
else
{
static assert(0);
}
// Report error, where errno gives the error number
void errNo()
{
version (Win32)
{
throw new FileException(filename, GetLastError());
}
else version (linux)
{
throw new FileException(filename, getErrno());
}
else
{
static assert(0);
}
}
}
/*
version (Win32)
{
}
else version (linux)
{
}
else
{
static assert(0);
}
*/