opengnsys
/
ntfs-3g
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Major rewrite, in particular seek, read, and write related code. 

(Logical change 1.698)
edge.strict_endians
cantab.net!aia21 2005-04-22 13:52:16 +00:00
parent 032d26b4d4
commit 307659837c
1 changed files with 253 additions and 244 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

481
libntfs/win32_io.c
View File

@ -4,7 +4,7 @@
* Part of the Linux-NTFS project. * Part of the Linux-NTFS project.
* *
* Copyright (c) 2003-2004 Lode Leroy * Copyright (c) 2003-2004 Lode Leroy
* Copyright (c) 2003-2004 Anton Altaparmakov * Copyright (c) 2003-2005 Anton Altaparmakov
* *
* This program/include file is free software; you can redistribute it and/or * This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published * modify it under the terms of the GNU General Public License as published
@ -36,8 +36,8 @@
* Cannot use "../include/types.h" since it conflicts with "wintypes.h". * Cannot use "../include/types.h" since it conflicts with "wintypes.h".
* define our own... * define our own...
*/ */
typedef long long int s64; typedef long long s64;
typedef unsigned long int u32; typedef unsigned long u32;
struct stat; struct stat;
struct ntfs_volume; struct ntfs_volume;
typedef struct ntfs_volume ntfs_volume; typedef struct ntfs_volume ntfs_volume;
@ -72,7 +72,8 @@ typedef struct win32_fd {
int part_hidden_sectors; int part_hidden_sectors;
s64 part_start; s64 part_start;
s64 part_length; s64 part_length;
LARGE_INTEGER current_pos; s64 real_pos;
int real_ofs;
s64 geo_size, geo_cylinders; s64 geo_size, geo_cylinders;
DWORD geo_sectors, geo_heads; DWORD geo_sectors, geo_heads;
HANDLE vol_handle; HANDLE vol_handle;
@ -366,7 +367,7 @@ static s64 ntfs_device_win32_getntfssize(HANDLE handle)
* In Windows XP+: fills the members: size, sectors, cylinders and heads. * In Windows XP+: fills the members: size, sectors, cylinders and heads.
* *
* Note: in pre XP, this requires write permission, even though nothing is * Note: in pre XP, this requires write permission, even though nothing is
* actuallt written. * actually written.
* *
* if fails, set sectors, cylinders and heads to -1. * if fails, set sectors, cylinders and heads to -1.
*/ */
@ -478,7 +479,8 @@ static __inline__ int ntfs_device_win32_open_file(char *filename, win32_fd *fd,
fd->handle = handle; fd->handle = handle;
fd->part_start = 0; fd->part_start = 0;
fd->part_length = ntfs_device_win32_getsize(handle); fd->part_length = ntfs_device_win32_getsize(handle);
fd->current_pos.QuadPart = 0; fd->real_pos = 0;
fd->real_ofs = 0;
fd->part_hidden_sectors = -1; fd->part_hidden_sectors = -1;
fd->geo_size = -1; /* used as a marker that this is a file */ fd->geo_size = -1; /* used as a marker that this is a file */
fd->vol_handle = INVALID_HANDLE_VALUE; fd->vol_handle = INVALID_HANDLE_VALUE;
@ -520,7 +522,8 @@ static __inline__ int ntfs_device_win32_open_drive(int drive_id, win32_fd *fd,
fd->handle = handle; fd->handle = handle;
fd->part_start = 0; fd->part_start = 0;
fd->part_length = fd->geo_size; fd->part_length = fd->geo_size;
fd->current_pos.QuadPart = 0; fd->real_pos = 0;
fd->real_ofs = 0;
fd->part_hidden_sectors = -1; fd->part_hidden_sectors = -1;
fd->vol_handle = INVALID_HANDLE_VALUE; fd->vol_handle = INVALID_HANDLE_VALUE;
@ -699,7 +702,8 @@ static int ntfs_device_win32_open_partition(int drive_id,
ntfs_device_win32_getgeo(handle, fd); ntfs_device_win32_getgeo(handle, fd);
fd->handle = handle; fd->handle = handle;
fd->current_pos.QuadPart = 0; fd->real_pos = 0;
fd->real_ofs = 0;
fd->part_start = part_start; fd->part_start = part_start;
fd->part_length = part_length; fd->part_length = part_length;
fd->part_hidden_sectors = hidden_sectors; fd->part_hidden_sectors = hidden_sectors;
@ -814,40 +818,38 @@ static int ntfs_device_win32_open(struct ntfs_device *dev, int flags)
* Return Succeed: The new position in the file * Return Succeed: The new position in the file
* Fail: -1 and errno set. * Fail: -1 and errno set.
*/ */
static s64 ntfs_device_win32_abs_seek(struct win32_fd *fd, LARGE_INTEGER pos) static s64 ntfs_device_win32_abs_seek(struct win32_fd *fd, s64 pos)
{ {
if ((pos.QuadPart < 0) || (pos.QuadPart > fd->part_length)) { LARGE_INTEGER li;
HANDLE handle;
if (pos < 0 || pos > fd->part_length) {
Dputs("Error: Seeking outsize seekable area."); Dputs("Error: Seeking outsize seekable area.");
errno = EINVAL; errno = EINVAL;
return -1; return -1;
} }
li.QuadPart = pos;
if (!(pos.QuadPart & 0x1FF)) { if (fd->vol_handle != INVALID_HANDLE_VALUE && pos < fd->geo_size) {
LARGE_INTEGER pos2;
HANDLE handle;
if ((fd->vol_handle != INVALID_HANDLE_VALUE) &&
(pos.QuadPart < fd->geo_size)) {
Dputs("Seeking via vol_handle"); Dputs("Seeking via vol_handle");
handle = fd->vol_handle; handle = fd->vol_handle;
pos2.QuadPart = pos.QuadPart;
} else { } else {
Dputs("Seeking via handle"); Dputs("Seeking via handle");
handle = fd->handle; handle = fd->handle;
pos2.QuadPart = pos.QuadPart + fd->part_start; li.QuadPart += fd->part_start;
} }
if (!SetFilePointerEx(handle, pos2, NULL, FILE_BEGIN)) { /* If the address is not alligned, we round down to nearest sector. */
li.QuadPart &= ~(s64)(NTFS_BLOCK_SIZE - 1);
/* Only seek if we are not there already. */
if (li.QuadPart != fd->real_pos) {
if (!SetFilePointerEx(handle, li, NULL, FILE_BEGIN)) {
errno = ntfs_w32error_to_errno(GetLastError()); errno = ntfs_w32error_to_errno(GetLastError());
Dputs("Error: SetFilePointer failed."); Dputs("Error: SetFilePointer failed.");
return -1; return -1;
} }
fd->real_pos = li.QuadPart;
} }
fd->real_ofs = pos & (NTFS_BLOCK_SIZE - 1);
/* Notice: If the address is not alligned, we leave it for the return pos;
read/write operation. */
fd->current_pos.QuadPart = pos.QuadPart;
return pos.QuadPart;
} }
/** /**
@ -865,17 +867,16 @@ static s64 ntfs_device_win32_abs_seek(struct win32_fd *fd, LARGE_INTEGER pos)
static s64 ntfs_device_win32_seek(struct ntfs_device *dev, s64 offset, static s64 ntfs_device_win32_seek(struct ntfs_device *dev, s64 offset,
int whence) int whence)
{ {
LARGE_INTEGER abs_offset; s64 abs_ofs;
struct win32_fd *fd = (win32_fd *)dev->d_private; struct win32_fd *fd = (win32_fd *)dev->d_private;
Dprintf("win32_seek(%lld=0x%llx,%d)\n", offset, offset, whence); Dprintf("win32_seek(%lld=0x%llx,%d)\n", offset, offset, whence);
switch (whence) { switch (whence) {
case SEEK_SET: case SEEK_SET:
abs_offset.QuadPart = offset; abs_ofs = offset;
break; break;
case SEEK_CUR: case SEEK_CUR:
abs_offset.QuadPart = fd->current_pos.QuadPart + offset; abs_ofs = fd->real_pos + fd->real_ofs + offset;
break; break;
case SEEK_END: case SEEK_END:
/* end of partition != end of disk */ /* end of partition != end of disk */
@ -885,64 +886,56 @@ static s64 ntfs_device_win32_seek(struct ntfs_device *dev, s64 offset,
errno = ENOTSUP; errno = ENOTSUP;
return -1; return -1;
} }
abs_offset.QuadPart = fd->part_length + offset; abs_ofs = fd->part_length + offset;
break; break;
default: default:
Dprintf("win32_seek() wrong mode %d.\n", whence); Dprintf("win32_seek() wrong mode %d.\n", whence);
errno = EINVAL; errno = EINVAL;
return -1; return -1;
} }
return ntfs_device_win32_abs_seek(fd, abs_ofs);
return ntfs_device_win32_abs_seek(fd, abs_offset);
} }
/** /**
* ntfs_device_win32_read_simple - Positioned simple read. * ntfs_device_win32_read_simple - Positioned simple read.
* @fd: The private data of the NTFS_DEVICE. * @fd: The private data of the NTFS_DEVICE.
* @pos: Absolute offset in the file.
* @buf: A pointer to where to put the contents. * @buf: A pointer to where to put the contents.
* @count: How many bytes should be read. * @count: How many bytes should be read.
* *
* On success returns the number of bytes read (could be <count) * On success returns the number of bytes read (can be < @count) and on error
* otherwise ((DWORD)-1) with errno. * returns (DWORD)-1 and errno set.
* *
* Note: * Notes:
* As count must be a multiple of the sector size, ((DWORD)-1) never * - Reads from fd->real_pos NOT considering fd->real_ofs.
* successfully occur. * - Does NOT advance fd->real_pos and fd->real_ofs.
* * - @buf must be aligned to page boundary.
* Limitations: * - @count must be a multiple of the sector size.
* buf must be aligned to page boundery * - When dealing with volumes, a single call must not span both volume
* pos & count must be aligned to sector bounderies.
* When dealing with volumes, a single call must not span both volume
* and disk extents. * and disk extents.
*/ */
static DWORD ntfs_device_win32_read_simple(win32_fd *fd, void *buf, static DWORD ntfs_device_win32_read_simple(win32_fd *fd, void *buf, DWORD count)
DWORD count)
{ {
HANDLE handle; HANDLE handle;
DWORD rvl, i; DWORD br;
if ((fd->geo_size > fd->current_pos.QuadPart) && if (fd->real_pos + fd->real_ofs < fd->geo_size &&
(fd->vol_handle != INVALID_HANDLE_VALUE)) { fd->vol_handle != INVALID_HANDLE_VALUE) {
Dputs("Reading via vol_handle"); Dputs("Reading via vol_handle.");
handle = fd->vol_handle; handle = fd->vol_handle;
} else { } else {
Dputs("Reading via handle"); Dputs("Reading via handle.");
handle = fd->handle; handle = fd->handle;
} }
if (!ReadFile(handle, buf, count, &br, NULL)) {
rvl = ReadFile(handle, buf, count, &i, (LPOVERLAPPED)NULL);
if (!rvl) {
errno = ntfs_w32error_to_errno(GetLastError()); errno = ntfs_w32error_to_errno(GetLastError());
Dputs("Error: ReadFile failed."); Dputs("Error: ReadFile() failed.");
return -1; return (DWORD)-1;
} else if (!i) {
errno = ENXIO;
Dputs("Error: ReadFile failed: EOF.");
return -1;
} }
/*
return i; * NOTE: The caller *MUST* update fd->real_pos and fd->real_ofs!!!
* Alternatively, caller can call ntfs_device_win32_{,abs_}seek().
*/
return br;
} }
/** /**
@ -956,77 +949,80 @@ static DWORD ntfs_device_win32_read_simple(win32_fd *fd, void *buf,
*/ */
static s64 ntfs_device_win32_read(struct ntfs_device *dev, void *buf, s64 count) static s64 ntfs_device_win32_read(struct ntfs_device *dev, void *buf, s64 count)
{ {
s64 pos, to_read;
struct win32_fd *fd = (win32_fd *)dev->d_private; struct win32_fd *fd = (win32_fd *)dev->d_private;
LARGE_INTEGER base, offset, numtoread;
BYTE *alignedbuffer; BYTE *alignedbuffer;
DWORD i, numread = 0; int old_ofs;
DWORD i, br = 0;
offset.QuadPart = fd->current_pos.QuadPart & 0x1FF; old_ofs = fd->real_ofs;
base.QuadPart = fd->current_pos.QuadPart - offset.QuadPart; pos = fd->real_pos + old_ofs;
numtoread.QuadPart = ((count + offset.QuadPart - 1) | 0x1FF) + 1; to_read = (old_ofs + count + NTFS_BLOCK_SIZE - 1) &
~(s64)(NTFS_BLOCK_SIZE - 1);
Dprintf("win32_read(fd=%p,b=%p,count=0x%llx)->(%llx+%llx:%llx)\n", fd, /* Impose maximum of 2GB to be on the safe side. */
buf, count, base.QuadPart, offset.QuadPart, if (to_read > 0x80000000) {
numtoread.QuadPart); int delta = to_read - count;
to_read = 0x80000000;
if (((((long)buf) & ((s64)0x1FF)) == 0) && ((count & ((s64)0x1FF)) == 0) count = to_read - delta;
&& ((fd->current_pos.QuadPart & 0x1FF) == 0)) { }
Dprintf("win32_read(fd=%p,b=%p,count=0x%llx)->(%llx+%x:%llx)\n", fd,
buf, count, (long long)fd->real_pos, old_ofs,
(long long)to_read);
if (!((unsigned long)buf & (NTFS_BLOCK_SIZE - 1)) && !old_ofs &&
!(count & (NTFS_BLOCK_SIZE - 1)))
alignedbuffer = buf; alignedbuffer = buf;
} else { else {
alignedbuffer = (BYTE *)VirtualAlloc(NULL, numtoread.LowPart, alignedbuffer = (BYTE *)VirtualAlloc(NULL, to_read, MEM_COMMIT,
MEM_COMMIT, PAGE_READWRITE); PAGE_READWRITE);
if (alignedbuffer == NULL) { if (!alignedbuffer) {
errno = ntfs_w32error_to_errno(GetLastError()); errno = ntfs_w32error_to_errno(GetLastError());
Dputs("Error: VirtualAlloc failed for read."); Dputs("Error: VirtualAlloc failed for read.");
return -1; return -1;
} }
} }
if (fd->vol_handle != INVALID_HANDLE_VALUE && pos < fd->geo_size) {
/* seek to base, if we are not in place */ s64 vol_to_read = fd->geo_size - pos;
if ((fd->current_pos.QuadPart & 0x1FF) && if (count > vol_to_read) {
(ntfs_device_win32_abs_seek(fd, base) == -1)) br = ntfs_device_win32_read_simple(fd,
alignedbuffer, old_ofs + vol_to_read);
if (br == (DWORD)-1)
goto read_error; goto read_error;
to_read -= br;
if ((fd->vol_handle != INVALID_HANDLE_VALUE) && if (br < old_ofs) {
(fd->current_pos.QuadPart < fd->geo_size)) { br = 0;
s64 vol_numtoread = fd->geo_size - fd->current_pos.QuadPart;
if (count > vol_numtoread) {
numread = ntfs_device_win32_read_simple(fd,
(LPVOID)alignedbuffer, vol_numtoread);
if (numread==(DWORD)-1)
goto read_error;
if (numread!=vol_numtoread)
goto read_partial; goto read_partial;
}
base.QuadPart = fd->geo_size; br -= old_ofs;
numtoread.QuadPart -= numread; pos += br;
if (ntfs_device_win32_abs_seek(fd, base) == -1) fd->real_pos = pos & ~(s64)(NTFS_BLOCK_SIZE - 1);
fd->real_ofs = pos & (NTFS_BLOCK_SIZE - 1);
if (br != vol_to_read)
goto read_partial; goto read_partial;
} }
} }
if ((i = ntfs_device_win32_read_simple(fd, alignedbuffer + br,
if ((i = ntfs_device_win32_read_simple(fd, (LPVOID)(alignedbuffer + to_read)) == (DWORD)-1) {
numread), numtoread.QuadPart)) == (DWORD)-1) { if (br)
if (numread>0)
goto read_partial; goto read_partial;
goto read_error; goto read_error;
} }
numread += i; if (i < fd->real_ofs)
goto read_partial;
i -= fd->real_ofs;
br += i;
if (br > count)
br = count;
pos += br;
fd->real_pos = pos & ~(s64)(NTFS_BLOCK_SIZE - 1);
fd->real_ofs = pos & (NTFS_BLOCK_SIZE - 1);
read_partial: read_partial:
numread = (numread < offset.LowPart) ? 0 : ((numread - offset.LowPart > if (alignedbuffer != buf) {
count) ? count : (numread - offset.LowPart)); memcpy((void*)buf, alignedbuffer + old_ofs, br);
fd->current_pos.QuadPart += numread;
if (buf != alignedbuffer) {
memcpy((void *)buf, alignedbuffer + offset.QuadPart, numread);
VirtualFree(alignedbuffer, 0, MEM_RELEASE); VirtualFree(alignedbuffer, 0, MEM_RELEASE);
} }
return br;
return numread;
read_error: read_error:
if (buf != alignedbuffer) if (alignedbuffer != buf)
VirtualFree(alignedbuffer, 0, MEM_RELEASE); VirtualFree(alignedbuffer, 0, MEM_RELEASE);
return -1; return -1;
} }
@ -1045,12 +1041,10 @@ static int ntfs_device_win32_close(struct ntfs_device *dev)
BOOL rvl; BOOL rvl;
Dprintf("win32_close(%p)\n", dev); Dprintf("win32_close(%p)\n", dev);
if (!NDevOpen(dev)) { if (!NDevOpen(dev)) {
errno = EBADF; errno = EBADF;
return -errno; return -errno;
} }
if (fd->vol_handle != INVALID_HANDLE_VALUE) { if (fd->vol_handle != INVALID_HANDLE_VALUE) {
if (!NDevReadOnly(dev)) { if (!NDevReadOnly(dev)) {
ntfs_device_win32_dismount(fd->vol_handle); ntfs_device_win32_dismount(fd->vol_handle);
@ -1059,17 +1053,13 @@ static int ntfs_device_win32_close(struct ntfs_device *dev)
if (!CloseHandle(fd->vol_handle)) if (!CloseHandle(fd->vol_handle))
Dputs("Error: CloseHandle failed for volume."); Dputs("Error: CloseHandle failed for volume.");
} }
rvl = CloseHandle(fd->handle); rvl = CloseHandle(fd->handle);
free(fd); free(fd);
if (!rvl) { if (!rvl) {
errno = ntfs_w32error_to_errno(GetLastError()); errno = ntfs_w32error_to_errno(GetLastError());
Dputs("Error: CloseHandle failed."); Dputs("Error: CloseHandle failed.");
return -1; return -1;
} }
return 0; return 0;
} }
@ -1085,32 +1075,30 @@ static int ntfs_device_win32_close(struct ntfs_device *dev)
*/ */
static int ntfs_device_win32_sync(struct ntfs_device *dev) static int ntfs_device_win32_sync(struct ntfs_device *dev)
{ {
int err = 0;
BOOL to_clear = TRUE;
if (!NDevReadOnly(dev) && NDevDirty(dev)) { if (!NDevReadOnly(dev) && NDevDirty(dev)) {
struct win32_fd *fd = (win32_fd *)dev->d_private; struct win32_fd *fd = (win32_fd *)dev->d_private;
if ((fd->vol_handle != INVALID_HANDLE_VALUE) && if ((fd->vol_handle != INVALID_HANDLE_VALUE) &&
FlushFileBuffers(fd->handle)) !FlushFileBuffers(fd->vol_handle)) {
NDevClearDirty(dev); to_clear = FALSE;
err = ntfs_w32error_to_errno(GetLastError());
if (FlushFileBuffers(fd->handle)) { }
NDevClearDirty(dev); if (!FlushFileBuffers(fd->handle)) {
return 0; to_clear = FALSE;
} else { if (!err)
/* We want to set errno even if we return 0 to err = ntfs_w32error_to_errno(GetLastError());
let the user to know about failure even in }
the disk/volume case. */ if (!to_clear) {
errno = ntfs_w32error_to_errno(GetLastError()); errno = err;
/* Don't fail in case of volume/disk */ Dputs("Error: Could not sync.");
if (fd->geo_size != -1)
return 0;
/* fail on the other cases */
Dputs("Error: Couldn't sync.");
return -1; return -1;
} }
} else { NDevClearDirty(dev);
/* no need/ability for a sync(), just exit gracefully */
return 0;
} }
return 0;
} }
/** /**
@ -1120,31 +1108,41 @@ static int ntfs_device_win32_sync(struct ntfs_device *dev)
* @count: How many bytes should be written. * @count: How many bytes should be written.
* *
* On success returns the amount of bytes actually written. * On success returns the amount of bytes actually written.
* On fail returns -1 and errno set. * On success returns the number of bytes written and on error returns
* (DWORD)-1 and errno set.
* *
* Limitations: * Notes:
* buf must be aligned to page boundery * - Writes to fd->real_pos NOT considering fd->real_ofs.
* pos & count must be aligned to sector bounderies. * - Does NOT advance fd->real_pos and fd->real_ofs.
* When dealing with volumes, a single call must not span both volume and disk * - @buf must be aligned to page boundary.
* extents. * - @count must be a multiple of the sector size.
* - When dealing with volumes, a single call must not span both volume
* and disk extents.
*/ */
static DWORD ntfs_device_win32_write_simple(win32_fd *fd, static DWORD ntfs_device_win32_write_simple(win32_fd *fd, const void *buf,
const void *buf, DWORD count) DWORD count)
{ {
DWORD rvl, i; HANDLE handle;
DWORD bw;
if ((fd->geo_size > fd->current_pos.QuadPart) && if (fd->real_pos + fd->real_ofs < fd->geo_size &&
(fd->vol_handle != INVALID_HANDLE_VALUE)) fd->vol_handle != INVALID_HANDLE_VALUE) {
rvl = WriteFile(fd->vol_handle, buf, count, &i, NULL); Dputs("Writing via vol_handle");
else handle = fd->vol_handle;
rvl = WriteFile(fd->handle, buf, count, &i, NULL); } else {
Dputs("Writing via handle");
if (!rvl) { handle = fd->handle;
}
if (!WriteFile(handle, buf, count, &bw, NULL)) {
errno = ntfs_w32error_to_errno(GetLastError()); errno = ntfs_w32error_to_errno(GetLastError());
Dputs("Error: WriteFile failed."); Dputs("Error: WriteFile failed.");
return (DWORD)-1; return (DWORD)-1;
} }
return i; /*
* NOTE: The caller *MUST* update fd->real_pos and fd->real_ofs!!!
* Alternatively, caller can call ntfs_device_win32_{,abs_}seek().
*/
return bw;
} }
/** /**
@ -1159,111 +1157,122 @@ static DWORD ntfs_device_win32_write_simple(win32_fd *fd,
static s64 ntfs_device_win32_write(struct ntfs_device *dev, const void *buf, static s64 ntfs_device_win32_write(struct ntfs_device *dev, const void *buf,
s64 count) s64 count)
{ {
s64 pos, to_write;
win32_fd *fd = (win32_fd *)dev->d_private; win32_fd *fd = (win32_fd *)dev->d_private;
LARGE_INTEGER base, offset, actual_count; BYTE *alignedbuffer;
BYTE *alignedbuffer = NULL; int old_ofs;
DWORD i; DWORD i, bw = 0;
Dprintf("win32_write: Writing %lld bytes\n",count);
Dprintf("win32_write: Writing %lld bytes\n", (long long)count);
if (NDevReadOnly(dev)) { if (NDevReadOnly(dev)) {
Dputs("win32_write: Device R/O, exiting."); Dputs("win32_write: Device R/O, exiting.");
errno = EROFS; errno = EROFS;
return -1; return -1;
} }
if (!count) if (!count)
return 0; return 0;
NDevSetDirty(dev); NDevSetDirty(dev);
old_ofs = fd->real_ofs;
offset.QuadPart = fd->current_pos.QuadPart & 0x1FF; pos = fd->real_pos + old_ofs;
base.QuadPart = fd->current_pos.QuadPart - offset.QuadPart; to_write = (old_ofs + count + NTFS_BLOCK_SIZE - 1) &
actual_count.QuadPart = ((count + offset.QuadPart - 1) | 0x1FF) + 1; ~(s64)(NTFS_BLOCK_SIZE - 1);
/* Impose maximum of 2GB to be on the safe side. */
if ((actual_count.QuadPart != count) || (((long)buf) & 0x1FF) || if (to_write > 0x80000000) {
(fd->current_pos.QuadPart & 0x1FF)) { int delta = to_write - count;
alignedbuffer = (BYTE *)VirtualAlloc(NULL, to_write = 0x80000000;
actual_count.QuadPart, MEM_COMMIT, PAGE_READWRITE); count = to_write - delta;
if (alignedbuffer == NULL) { }
if (!((unsigned long)buf & (NTFS_BLOCK_SIZE - 1)) && !old_ofs &&
!(count & (NTFS_BLOCK_SIZE - 1)))
alignedbuffer = buf;
else {
alignedbuffer = (BYTE *)VirtualAlloc(NULL, to_write,
MEM_COMMIT, PAGE_READWRITE);
if (!alignedbuffer) {
errno = ntfs_w32error_to_errno(GetLastError()); errno = ntfs_w32error_to_errno(GetLastError());
Dputs("Error: VirtualAlloc failed for write."); Dputs("Error: VirtualAlloc failed for write.");
return -1; return -1;
} }
/* Read first sector if start of write not sector aligned. */
/* read last sector */ if (old_ofs) {
if ((offset.QuadPart + count) & 0x1FF) { i = ntfs_device_win32_read_simple(fd, alignedbuffer,
LARGE_INTEGER pos; NTFS_BLOCK_SIZE);
pos.QuadPart = base.QuadPart + actual_count.QuadPart - if (i != NTFS_BLOCK_SIZE) {
512; if (i >= 0)
if (ntfs_device_win32_abs_seek(fd, pos) == -1) errno = EIO;
goto write_error;
if (!ntfs_device_win32_read_simple(fd,
(LPVOID)(alignedbuffer +
actual_count.QuadPart - 512), 512))
goto write_error;
}
/* read first sector */
if (offset.LowPart) {
if (ntfs_device_win32_abs_seek(fd, base) == -1)
goto write_error;
if (!ntfs_device_win32_read_simple(fd,
(LPVOID)(alignedbuffer), 512)) {
goto write_error; goto write_error;
} }
} }
/* Read last sector if end of write not sector aligned. */
/* copy the rest of the contents */ if ((pos + count) & (NTFS_BLOCK_SIZE - 1)) {
memcpy((void *)(alignedbuffer + offset.LowPart), buf, if (ntfs_device_win32_abs_seek(fd, (pos + count) &
(size_t)count); ~(NTFS_BLOCK_SIZE - 1)) == -1)
/* ReAligning */
if (ntfs_device_win32_abs_seek(fd, base) == -1)
goto write_error; goto write_error;
i = ntfs_device_win32_read_simple(fd, alignedbuffer +
/* hack to share code */ to_write - NTFS_BLOCK_SIZE,
buf = (const void *)alignedbuffer; NTFS_BLOCK_SIZE);
if (i != NTFS_BLOCK_SIZE) {
if (ntfs_device_win32_abs_seek(fd, pos) == -1) {
fd->real_pos = pos & ~(s64)
(NTFS_BLOCK_SIZE - 1);
fd->real_ofs = old_ofs;
} }
if (i >= 0)
if ((fd->geo_size > base.QuadPart) && errno = EIO;
(fd->vol_handle != INVALID_HANDLE_VALUE)) {
s64 tmp = min((fd->geo_size - base.QuadPart),
actual_count.QuadPart);
i = ntfs_device_win32_write_simple(fd, buf, tmp);
if (i == (DWORD)-1)
goto write_error;
if (i != tmp)
goto partial_write;
base.QuadPart -= i;
} else
i = 0;
if (fd->geo_size <= base.QuadPart) {
const void *newp = (const void *)(((const BYTE *)buf) + i);
i += ntfs_device_win32_write_simple(fd, newp,
actual_count.LowPart - i);
if (!i || (i == (DWORD)-1))
goto write_error; goto write_error;
} }
partial_write: }
if (alignedbuffer) /* Move the file position back so we can start writing. */
if (ntfs_device_win32_abs_seek(fd, pos) == -1) {
fd->real_pos = pos & ~(s64)(NTFS_BLOCK_SIZE - 1);
fd->real_ofs = old_ofs;
goto write_error;
}
/* Copy the data to be written into @alignedbuffer. */
memcpy(alignedbuffer + old_ofs, buf, count);
}
if (fd->vol_handle != INVALID_HANDLE_VALUE && pos < fd->geo_size) {
s64 vol_to_write = fd->geo_size - pos;
if (count > vol_to_read) {
bw = ntfs_device_win32_write_simple(fd, alignedbuffer,
old_ofs + vol_to_write);
if (bw == (DWORD)-1)
goto write_error;
to_write -= bw;
if (bw < old_ofs) {
bw = 0;
goto write_partial;
}
bw -= old_ofs;
pos += bw;
fd->real_pos = pos & ~(s64)(NTFS_BLOCK_SIZE - 1);
fd->real_ofs = pos & (NTFS_BLOCK_SIZE - 1);
if (bw != vol_to_write)
goto write_partial;
}
}
if ((i = ntfs_device_win32_write_simple(fd, alignedbuffer + bw,
to_write)) == (DWORD)-1) {
if (bw)
goto write_partial;
goto write_error;
}
if (i < fd->real_ofs)
goto write_partial;
i -= fd->real_ofs;
bw += i;
if (bw > count)
bw = count;
pos += bw;
fd->real_pos = pos & ~(s64)(NTFS_BLOCK_SIZE - 1);
fd->real_ofs = pos & (NTFS_BLOCK_SIZE - 1);
write_partial:
if (alignedbuffer != buf)
VirtualFree(alignedbuffer, 0, MEM_RELEASE); VirtualFree(alignedbuffer, 0, MEM_RELEASE);
return bw;
actual_count.QuadPart = (s64)i - actual_count.QuadPart + count;
if (actual_count.QuadPart < 0)
return 0;
return actual_count.QuadPart;
write_error: write_error:
if (alignedbuffer) bw = -1;
VirtualFree(alignedbuffer, 0, MEM_RELEASE); goto write_partial;
fd->current_pos.QuadPart = base.QuadPart + offset.QuadPart;
if (!(fd->current_pos.QuadPart & 512))
ntfs_device_win32_abs_seek(fd, base);
return -1;
} }
/** /**