Beta match MXIOINFO (#853)

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MS 2024-04-26 04:57:10 -04:00 committed by GitHub
parent 612eec6889
commit a9d67e4dd7
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2 changed files with 212 additions and 76 deletions

View file

@ -18,11 +18,13 @@ class MXIOINFO {
MxU16 Open(const char*, MxULong); MxU16 Open(const char*, MxULong);
MxU16 Close(MxLong); MxU16 Close(MxLong);
MxLong Read(void*, MxLong); MxLong Read(void*, MxLong);
MxLong Write(void*, MxLong);
MxLong Seek(MxLong, MxLong); MxLong Seek(MxLong, MxLong);
MxU16 SetBuffer(char*, MxLong, MxLong); MxU16 SetBuffer(char*, MxLong, MxLong);
MxU16 Flush(MxU16); MxU16 Flush(MxU16);
MxU16 Advance(MxU16); MxU16 Advance(MxU16);
MxU16 Descend(MMCKINFO*, const MMCKINFO*, MxU16); MxU16 Descend(MMCKINFO*, const MMCKINFO*, MxU16);
MxU16 Ascend(MMCKINFO*, MxU16);
// NOTE: In MXIOINFO, the `hmmio` member of MMIOINFO is used like // NOTE: In MXIOINFO, the `hmmio` member of MMIOINFO is used like
// an HFILE (int) instead of an HMMIO (WORD). // an HFILE (int) instead of an HMMIO (WORD).

View file

@ -2,56 +2,63 @@
#include "decomp.h" #include "decomp.h"
#include <assert.h>
// This class should be 72 bytes in size, same as the MMIOINFO struct. // This class should be 72 bytes in size, same as the MMIOINFO struct.
// The current implementation has MMIOINFO as the only member of the class, // The current implementation has MMIOINFO as the only member of the class,
// but this assert will enforce the size if we decide to change that. // but this assert will enforce the size if we decide to change that.
DECOMP_SIZE_ASSERT(MXIOINFO, sizeof(MMIOINFO)); DECOMP_SIZE_ASSERT(MXIOINFO, sizeof(MMIOINFO));
// FUNCTION: LEGO1 0x100cc800 // FUNCTION: LEGO1 0x100cc800
// FUNCTION: BETA10 0x1015e140
MXIOINFO::MXIOINFO() MXIOINFO::MXIOINFO()
{ {
memset(&m_info, 0, sizeof(m_info)); memset(&m_info, 0, sizeof(m_info));
} }
// FUNCTION: LEGO1 0x100cc820 // FUNCTION: LEGO1 0x100cc820
// FUNCTION: BETA10 0x1015e169
MXIOINFO::~MXIOINFO() MXIOINFO::~MXIOINFO()
{ {
Close(0); Close(0);
} }
// FUNCTION: LEGO1 0x100cc830 // FUNCTION: LEGO1 0x100cc830
// FUNCTION: BETA10 0x1015e189
MxU16 MXIOINFO::Open(const char* p_filename, MxULong p_flags) MxU16 MXIOINFO::Open(const char* p_filename, MxULong p_flags)
{ {
OFSTRUCT unused; OFSTRUCT unused;
MxU16 result = 0; MxU16 result = 0;
m_info.lBufOffset = 0; m_info.lDiskOffset = m_info.lBufOffset = 0;
m_info.lDiskOffset = 0;
// DECOMP: Cast of p_flags to u16 forces the `movzx` instruction // DECOMP: Cast of p_flags to u16 forces the `movzx` instruction
m_info.hmmio = (HMMIO) OpenFile(p_filename, &unused, (MxU16) p_flags); m_info.hmmio = (HMMIO) OpenFile(p_filename, &unused, (MxU16) p_flags);
if ((HFILE) m_info.hmmio != HFILE_ERROR) { if ((HFILE) m_info.hmmio != HFILE_ERROR) {
m_info.dwFlags = p_flags; m_info.dwFlags = p_flags;
if (p_flags & MMIO_ALLOCBUF) { if (m_info.dwFlags & MMIO_ALLOCBUF) {
// Default buffer length of 8k if none specified // Default buffer length of 8k if none specified
MxLong len = m_info.cchBuffer ? m_info.cchBuffer : 8192; MxLong len = m_info.cchBuffer;
HPSTR buf = new char[len]; if (len == 0) {
len = 8192;
}
char* buf = new char[len];
if (!buf) { if (!buf) {
result = MMIOERR_OUTOFMEMORY;
m_info.cchBuffer = 0;
m_info.dwFlags &= ~MMIO_ALLOCBUF; m_info.dwFlags &= ~MMIO_ALLOCBUF;
m_info.cchBuffer = 0;
m_info.pchBuffer = 0; m_info.pchBuffer = 0;
result = MMIOERR_OUTOFMEMORY;
} }
else { else {
m_info.pchBuffer = buf;
m_info.cchBuffer = len; m_info.cchBuffer = len;
m_info.pchBuffer = (HPSTR) buf;
} }
m_info.pchEndRead = m_info.pchBuffer; m_info.pchNext = m_info.pchEndRead = m_info.pchBuffer;
m_info.pchNext = m_info.pchBuffer;
m_info.pchEndWrite = m_info.pchBuffer + m_info.cchBuffer; m_info.pchEndWrite = m_info.pchBuffer + m_info.cchBuffer;
} }
} }
@ -63,6 +70,7 @@ MxU16 MXIOINFO::Open(const char* p_filename, MxULong p_flags)
} }
// FUNCTION: LEGO1 0x100cc8e0 // FUNCTION: LEGO1 0x100cc8e0
// FUNCTION: BETA10 0x1015e30b
MxU16 MXIOINFO::Close(MxLong p_unused) MxU16 MXIOINFO::Close(MxLong p_unused)
{ {
MxU16 result = 0; MxU16 result = 0;
@ -76,9 +84,7 @@ MxU16 MXIOINFO::Close(MxLong p_unused)
delete[] m_info.pchBuffer; delete[] m_info.pchBuffer;
} }
m_info.pchEndWrite = 0; m_info.pchBuffer = m_info.pchEndRead = m_info.pchEndWrite = NULL;
m_info.pchEndRead = 0;
m_info.pchBuffer = 0;
m_info.dwFlags = 0; m_info.dwFlags = 0;
} }
@ -86,6 +92,7 @@ MxU16 MXIOINFO::Close(MxLong p_unused)
} }
// FUNCTION: LEGO1 0x100cc930 // FUNCTION: LEGO1 0x100cc930
// FUNCTION: BETA10 0x1015e3b2
MxLong MXIOINFO::Read(void* p_buf, MxLong p_len) MxLong MXIOINFO::Read(void* p_buf, MxLong p_len)
{ {
MxLong bytesRead = 0; MxLong bytesRead = 0;
@ -101,22 +108,25 @@ MxLong MXIOINFO::Read(void* p_buf, MxLong p_len)
} }
memcpy(p_buf, m_info.pchNext, bytesLeft); memcpy(p_buf, m_info.pchNext, bytesLeft);
p_len -= bytesLeft;
m_info.pchNext += bytesLeft; m_info.pchNext += bytesLeft;
bytesRead += bytesLeft; bytesRead += bytesLeft;
p_len -= bytesLeft;
} }
if (p_len <= 0 || Advance(0)) { if (p_len > 0) {
if (Advance(MMIO_READ)) {
break; break;
} }
else {
bytesLeft = m_info.pchEndRead - m_info.pchNext; bytesLeft = m_info.pchEndRead - m_info.pchNext;
if (bytesLeft <= 0) { if (bytesLeft <= 0) {
break; break;
} }
} }
} }
}
}
else if (m_info.hmmio && p_len > 0) { else if (m_info.hmmio && p_len > 0) {
bytesRead = _hread((HFILE) m_info.hmmio, p_buf, p_len); bytesRead = _hread((HFILE) m_info.hmmio, p_buf, p_len);
@ -132,10 +142,69 @@ MxLong MXIOINFO::Read(void* p_buf, MxLong p_len)
return bytesRead; return bytesRead;
} }
// FUNCTION: BETA10 0x1015e4fc
MxLong MXIOINFO::Write(void* p_buf, MxLong p_len)
{
MxLong bytesWritten = 0;
if (m_info.pchBuffer) {
MxLong bytesLeft = m_info.pchEndWrite - m_info.pchNext;
while (p_len > 0) {
if (bytesLeft > 0) {
if (p_len < bytesLeft) {
bytesLeft = p_len;
}
memcpy(m_info.pchNext, p_buf, bytesLeft);
m_info.dwFlags |= MMIO_DIRTY;
m_info.pchNext += bytesLeft;
bytesWritten += bytesLeft;
p_len -= bytesLeft;
}
if (p_len > 0) {
if (Advance(MMIO_WRITE)) {
assert(0);
break;
}
else {
bytesLeft = m_info.pchEndWrite - m_info.pchNext;
if (bytesLeft <= 0) {
assert(0);
break;
}
}
}
}
}
else if (m_info.hmmio && p_len > 0) {
bytesWritten = _hwrite((HFILE) m_info.hmmio, (const char*) p_buf, p_len);
if (bytesWritten == -1) {
bytesWritten = 0;
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
}
else {
m_info.lDiskOffset += bytesWritten;
}
}
// DECOMP: This assert is just "pchNext <= pchEndWrite"
// That would suggest that MXIOINFO directly extends MMIOINFO.
// TODO: Change that if we still have entropy at the end.
assert(m_info.pchNext <= m_info.pchEndWrite);
return bytesWritten;
}
// FUNCTION: LEGO1 0x100cca00 // FUNCTION: LEGO1 0x100cca00
// FUNCTION: BETA10 0x1015e6c4
MxLong MXIOINFO::Seek(MxLong p_offset, MxLong p_origin) MxLong MXIOINFO::Seek(MxLong p_offset, MxLong p_origin)
{ {
MxLong result = -1; MxLong result = -1;
MxLong bytesRead;
// If buffered I/O // If buffered I/O
if (m_info.pchBuffer) { if (m_info.pchBuffer) {
@ -144,13 +213,12 @@ MxLong MXIOINFO::Seek(MxLong p_offset, MxLong p_origin)
// don't seek at all and just return where we are. // don't seek at all and just return where we are.
return m_info.lBufOffset + (m_info.pchNext - m_info.pchBuffer); return m_info.lBufOffset + (m_info.pchNext - m_info.pchBuffer);
} }
else {
// With SEEK_CUR, p_offset is a relative offset. // With SEEK_CUR, p_offset is a relative offset.
// Get the absolute position instead and use SEEK_SET. // Get the absolute position instead and use SEEK_SET.
p_offset += m_info.lBufOffset + (m_info.pchNext - m_info.pchBuffer); p_offset += m_info.lBufOffset + (m_info.pchNext - m_info.pchBuffer);
p_origin = SEEK_SET; p_origin = SEEK_SET;
} }
}
else if (p_origin == SEEK_END) { else if (p_origin == SEEK_END) {
// not possible with buffered I/O // not possible with buffered I/O
return -1; return -1;
@ -175,13 +243,12 @@ MxLong MXIOINFO::Seek(MxLong p_offset, MxLong p_origin)
else { else {
// align offset to buffer size // align offset to buffer size
MxLong newOffset = p_offset - (p_offset % m_info.cchBuffer); m_info.lBufOffset = p_offset - (p_offset % m_info.cchBuffer);
m_info.lBufOffset = newOffset;
// do we need to seek again? // do we need to seek again?
// (i.e. are we already aligned to buffer size?) // (i.e. are we already aligned to buffer size?)
if (p_offset != newOffset) { if (p_offset != m_info.lBufOffset) {
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, newOffset, SEEK_SET); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, m_info.lBufOffset, SEEK_SET);
if (m_info.lDiskOffset == -1) { if (m_info.lDiskOffset == -1) {
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
@ -190,15 +257,9 @@ MxLong MXIOINFO::Seek(MxLong p_offset, MxLong p_origin)
if (m_info.lBufOffset == m_info.lDiskOffset) { if (m_info.lBufOffset == m_info.lDiskOffset) {
// is the file open for writing only? // is the file open for writing only?
if ((m_info.dwFlags & MMIO_RWMODE) && ((m_info.dwFlags & MMIO_RWMODE) != MMIO_READWRITE)) { if ((m_info.dwFlags & MMIO_RWMODE) == 0 || (m_info.dwFlags & MMIO_RWMODE) == MMIO_READWRITE) {
m_info.pchNext = m_info.pchBuffer - m_info.lBufOffset + p_offset;
result = p_offset;
}
else {
// We can read from the file. Fill the buffer. // We can read from the file. Fill the buffer.
MxLong bytesRead = _hread((HFILE) m_info.hmmio, m_info.pchBuffer, m_info.cchBuffer); bytesRead = _hread((HFILE) m_info.hmmio, m_info.pchBuffer, m_info.cchBuffer);
if (bytesRead == -1) { if (bytesRead == -1) {
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
@ -213,19 +274,22 @@ MxLong MXIOINFO::Seek(MxLong p_offset, MxLong p_origin)
} }
} }
} }
}
}
}
}
}
else { else {
m_info.pchNext = p_offset - m_info.lBufOffset + m_info.pchBuffer;
result = p_offset;
}
}
}
}
}
}
else if (m_info.hmmio) {
// No buffer so just seek the file directly (if we have a valid handle) // No buffer so just seek the file directly (if we have a valid handle)
if (m_info.hmmio) {
// i.e. if we just want to get the current file position // i.e. if we just want to get the current file position
if (p_origin == SEEK_CUR && p_offset == 0) { if (p_origin == SEEK_CUR && p_offset == 0) {
return m_info.lDiskOffset; return m_info.lDiskOffset;
} }
else {
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, p_offset, p_origin); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, p_offset, p_origin);
result = m_info.lDiskOffset; result = m_info.lDiskOffset;
@ -234,16 +298,16 @@ MxLong MXIOINFO::Seek(MxLong p_offset, MxLong p_origin)
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
} }
} }
}
}
return result; return result;
} }
// FUNCTION: LEGO1 0x100ccbc0 // FUNCTION: LEGO1 0x100ccbc0
// FUNCTION: BETA10 0x1015e9ad
MxU16 MXIOINFO::SetBuffer(char* p_buf, MxLong p_len, MxLong p_unused) MxU16 MXIOINFO::SetBuffer(char* p_buf, MxLong p_len, MxLong p_unused)
{ {
MxU16 result = Flush(0); MxU16 result = 0;
result = Flush(0);
if (m_info.dwFlags & MMIO_ALLOCBUF) { if (m_info.dwFlags & MMIO_ALLOCBUF) {
m_info.dwFlags &= ~MMIO_ALLOCBUF; m_info.dwFlags &= ~MMIO_ALLOCBUF;
@ -259,9 +323,11 @@ MxU16 MXIOINFO::SetBuffer(char* p_buf, MxLong p_len, MxLong p_unused)
} }
// FUNCTION: LEGO1 0x100ccc10 // FUNCTION: LEGO1 0x100ccc10
// FUNCTION: BETA10 0x1015ea3e
MxU16 MXIOINFO::Flush(MxU16 p_unused) MxU16 MXIOINFO::Flush(MxU16 p_unused)
{ {
MxU16 result = 0; MxU16 result = 0;
MxLong bytesWritten;
// if buffer is dirty // if buffer is dirty
if (m_info.dwFlags & MMIO_DIRTY) { if (m_info.dwFlags & MMIO_DIRTY) {
@ -282,17 +348,17 @@ MxU16 MXIOINFO::Flush(MxU16 p_unused)
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
} }
else { else {
MxLong bytesWritten = _hwrite((HFILE) m_info.hmmio, m_info.pchBuffer, cchBuffer); bytesWritten = _hwrite((HFILE) m_info.hmmio, m_info.pchBuffer, cchBuffer);
if (bytesWritten != -1 && bytesWritten == cchBuffer) { if (bytesWritten == -1 || bytesWritten != cchBuffer) {
result = MMIOERR_CANNOTWRITE;
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
}
else {
m_info.lDiskOffset += bytesWritten; m_info.lDiskOffset += bytesWritten;
m_info.pchNext = m_info.pchBuffer; m_info.pchNext = m_info.pchBuffer;
m_info.dwFlags &= ~MMIO_DIRTY; m_info.dwFlags &= ~MMIO_DIRTY;
} }
else {
result = MMIOERR_CANNOTWRITE;
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
}
} }
} }
} }
@ -309,6 +375,7 @@ MxU16 MXIOINFO::Flush(MxU16 p_unused)
} }
// FUNCTION: LEGO1 0x100ccd00 // FUNCTION: LEGO1 0x100ccd00
// FUNCTION: BETA10 0x1015eb8f
MxU16 MXIOINFO::Advance(MxU16 p_option) MxU16 MXIOINFO::Advance(MxU16 p_option)
{ {
MxU16 result = 0; MxU16 result = 0;
@ -316,6 +383,7 @@ MxU16 MXIOINFO::Advance(MxU16 p_option)
if (m_info.pchBuffer) { if (m_info.pchBuffer) {
MxLong cch = m_info.cchBuffer; MxLong cch = m_info.cchBuffer;
MxLong bytesCounter;
// If we can and should write to the file, // If we can and should write to the file,
// if we are being asked to write to the file, // if we are being asked to write to the file,
@ -329,26 +397,24 @@ MxU16 MXIOINFO::Advance(MxU16 p_option)
if (m_info.lBufOffset != m_info.lDiskOffset) { if (m_info.lBufOffset != m_info.lDiskOffset) {
result = MMIOERR_CANNOTSEEK; result = MMIOERR_CANNOTSEEK;
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
} }
else { else {
MxLong bytesWritten = _hwrite((HFILE) m_info.hmmio, m_info.pchBuffer, cch); bytesCounter = _hwrite((HFILE) m_info.hmmio, m_info.pchBuffer, cch);
if (bytesWritten != -1 && bytesWritten == cch) { if (bytesCounter == -1 || bytesCounter != cch) {
m_info.lDiskOffset += bytesWritten; result = MMIOERR_CANNOTWRITE;
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
}
else {
m_info.lDiskOffset += bytesCounter;
m_info.pchNext = m_info.pchBuffer; m_info.pchNext = m_info.pchBuffer;
m_info.pchEndRead = m_info.pchBuffer; m_info.pchEndRead = m_info.pchBuffer;
m_info.dwFlags &= ~MMIO_DIRTY; m_info.dwFlags &= ~MMIO_DIRTY;
goto skipSeek;
} }
else {
result = MMIOERR_CANNOTWRITE;
} }
} }
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
}
skipSeek:
m_info.lBufOffset += cch; m_info.lBufOffset += cch;
if ((!rwmode || rwmode == MMIO_READWRITE) && cch > 0) { if ((!rwmode || rwmode == MMIO_READWRITE) && cch > 0) {
if (m_info.lBufOffset != m_info.lDiskOffset) { if (m_info.lBufOffset != m_info.lDiskOffset) {
@ -361,16 +427,16 @@ MxU16 MXIOINFO::Advance(MxU16 p_option)
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
} }
else { else {
MxLong bytesRead = _hread((HFILE) m_info.hmmio, m_info.pchBuffer, cch); bytesCounter = _hread((HFILE) m_info.hmmio, m_info.pchBuffer, cch);
if (bytesRead == -1) { if (bytesCounter == -1) {
result = MMIOERR_CANNOTREAD; result = MMIOERR_CANNOTREAD;
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR); m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
} }
else { else {
m_info.lDiskOffset += bytesRead; m_info.lDiskOffset += bytesCounter;
m_info.pchNext = m_info.pchBuffer; m_info.pchNext = m_info.pchBuffer;
m_info.pchEndRead = m_info.pchBuffer + bytesRead; m_info.pchEndRead = m_info.pchBuffer + bytesCounter;
} }
} }
} }
@ -383,9 +449,12 @@ MxU16 MXIOINFO::Advance(MxU16 p_option)
} }
// FUNCTION: LEGO1 0x100cce60 // FUNCTION: LEGO1 0x100cce60
// FUNCTION: BETA10 0x1015edef
MxU16 MXIOINFO::Descend(MMCKINFO* p_chunkInfo, const MMCKINFO* p_parentInfo, MxU16 p_descend) MxU16 MXIOINFO::Descend(MMCKINFO* p_chunkInfo, const MMCKINFO* p_parentInfo, MxU16 p_descend)
{ {
MxU16 result = 0; MxU16 result = 0;
MxULong ofs;
BOOL readOk;
if (!p_chunkInfo) { if (!p_chunkInfo) {
return MMIOERR_BASE; // ? return MMIOERR_BASE; // ?
@ -411,14 +480,14 @@ MxU16 MXIOINFO::Descend(MMCKINFO* p_chunkInfo, const MMCKINFO* p_parentInfo, MxU
} }
} }
else { else {
MxULong ofs = MAXLONG; ofs = MAXLONG;
if (p_parentInfo) { if (p_parentInfo) {
ofs = p_parentInfo->cksize + p_parentInfo->dwDataOffset; ofs = p_parentInfo->cksize + p_parentInfo->dwDataOffset;
} }
BOOL running = TRUE; BOOL running = TRUE;
BOOL readOk = FALSE; readOk = FALSE;
MMCKINFO tmp; MMCKINFO tmp;
tmp.dwFlags = 0; tmp.dwFlags = 0;
@ -461,9 +530,74 @@ MxU16 MXIOINFO::Descend(MMCKINFO* p_chunkInfo, const MMCKINFO* p_parentInfo, MxU
} }
if (!result) { if (!result) {
memcpy(p_chunkInfo, &tmp, sizeof(MMCKINFO)); // implicit memcpy
*p_chunkInfo = tmp;
} }
} }
return result; return result;
} }
// FUNCTION: BETA10 0x1015f08b
MxU16 MXIOINFO::Ascend(MMCKINFO* p_chunkInfo, MxU16 p_ascend)
{
MxLong ofs;
MxULong size;
MxU16 result = 0;
if (p_chunkInfo == NULL) {
return MMIOERR_BASE;
}
if (m_info.dwFlags & MMIO_RWMODE) {
if (m_info.pchBuffer) {
size = (MxULong) (m_info.pchNext - m_info.pchBuffer) + m_info.lBufOffset - p_chunkInfo->dwDataOffset;
}
else {
size = m_info.lDiskOffset - p_chunkInfo->dwDataOffset;
}
// Write a zero byte if the chunk size is odd
if (size & 1) {
Write(&result, 1);
}
if ((p_chunkInfo->dwFlags & MMIO_DIRTY) && p_chunkInfo->cksize != size) {
ofs = p_chunkInfo->dwDataOffset - 4;
// Correct chunk size
p_chunkInfo->cksize = size;
p_chunkInfo->dwFlags &= ~MMIO_DIRTY;
// Now write the corrected size
if (m_info.pchBuffer && ofs >= m_info.lBufOffset && m_info.cchBuffer + m_info.lBufOffset > ofs) {
memcpy(m_info.pchBuffer + (ofs - m_info.lBufOffset), (char*) &size, 4);
m_info.dwFlags |= MMIO_DIRTY;
}
else {
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, ofs, SEEK_SET);
if (m_info.lDiskOffset == ofs) {
if (_lwrite((HFILE) m_info.hmmio, (char*) &size, 4) != 4) {
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
result = MMIOERR_CANNOTWRITE;
}
else {
m_info.lDiskOffset += 4; // TODO: compiler weirdness?
}
}
else {
m_info.lDiskOffset = _llseek((HFILE) m_info.hmmio, 0, SEEK_CUR);
result = MMIOERR_CANNOTSEEK;
}
}
}
}
// Seek past the end of the chunk (plus optional pad byte if size is odd)
if (result == 0 &&
Seek((p_chunkInfo->cksize & 1) + p_chunkInfo->cksize + p_chunkInfo->dwDataOffset, SEEK_SET) == -1) {
result = MMIOERR_CANNOTSEEK;
}
return result;
}