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[NTVDM]

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The fix in r67477 was incorrect. When loading an executable high, we need to
allocate all of the memory and copy the program itself to the highest part of it.
I know it sounds illogical but that's how it works...


svn path=/trunk/; revision=67478
This commit is contained in:
Aleksandar Andrejevic 2015-04-29 03:18:02 +00:00
parent 294468d4e7
commit 5891e0a021
1 changed files with 28 additions and 27 deletions
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55
reactos/subsystems/mvdm/ntvdm/dos/dos32krnl/dos.c
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@ -292,12 +292,13 @@ DWORD DosLoadExecutable(IN DOS_EXEC_TYPE LoadType,
WORD Segment = 0;
WORD EnvBlock = 0;
WORD MaxAllocSize;
DWORD i, FileSize, ExeSize;
WORD ExeSegment;
DWORD i, FileSize, BaseSize, TotalSize;
PIMAGE_DOS_HEADER Header;
PDWORD RelocationTable;
PWORD RelocWord;
LPSTR CmdLinePtr = (LPSTR)CommandLine;
BYTE OldStrategy = DosAllocStrategy;
BOOLEAN LoadHigh = FALSE;
DPRINT1("DosLoadExecutable(%d, %s, %s, %s, 0x%08X, 0x%08X)\n",
LoadType,
@ -372,45 +373,46 @@ DWORD DosLoadExecutable(IN DOS_EXEC_TYPE LoadType,
Header = (PIMAGE_DOS_HEADER)Address;
/* Get the base size of the file, in paragraphs (rounded up) */
ExeSize = (((Header->e_cp - 1) * 512) + Header->e_cblp + 0x0F) >> 4;
BaseSize = TotalSize = (((Header->e_cp - 1) * 512) + Header->e_cblp + 0x0F) >> 4;
/* Add the PSP size, in paragraphs */
ExeSize += sizeof(DOS_PSP) >> 4;
TotalSize += sizeof(DOS_PSP) >> 4;
/* Add the maximum size that should be allocated */
ExeSize += Header->e_maxalloc;
/* Make sure it does not pass 0xFFFF */
if (ExeSize > 0xFFFF) ExeSize = 0xFFFF;
TotalSize += Header->e_maxalloc;
if (Header->e_minalloc == 0 && Header->e_maxalloc == 0)
{
/* This program should be loaded high */
DosAllocStrategy = DOS_ALLOC_LAST_FIT;
LoadHigh = TRUE;
TotalSize = 0xFFFF;
}
/* Make sure it does not pass 0xFFFF */
if (TotalSize > 0xFFFF) TotalSize = 0xFFFF;
/* Try to allocate that much memory */
Segment = DosAllocateMemory((WORD)ExeSize, &MaxAllocSize);
Segment = DosAllocateMemory((WORD)TotalSize, &MaxAllocSize);
if (Segment == 0)
{
/* Check if there's at least enough memory for the minimum size */
if (MaxAllocSize < (ExeSize - Header->e_maxalloc + Header->e_minalloc))
if (MaxAllocSize < (BaseSize + (sizeof(DOS_PSP) >> 4) + Header->e_minalloc))
{
Result = DosLastError;
goto Cleanup;
}
/* Allocate that minimum amount */
ExeSize = MaxAllocSize;
Segment = DosAllocateMemory((WORD)ExeSize, NULL);
TotalSize = MaxAllocSize;
Segment = DosAllocateMemory((WORD)TotalSize, NULL);
ASSERT(Segment != 0);
}
/* Initialize the PSP */
DosInitializePsp(Segment,
CommandLine,
(WORD)ExeSize,
(WORD)TotalSize,
EnvBlock,
ReturnAddress);
@ -418,11 +420,14 @@ DWORD DosLoadExecutable(IN DOS_EXEC_TYPE LoadType,
DosChangeMemoryOwner(Segment, Segment);
DosChangeMemoryOwner(EnvBlock, Segment);
/* Copy the program to Segment:0100 */
RtlCopyMemory(SEG_OFF_TO_PTR(Segment, 0x100),
/* Find the EXE segment */
if (!LoadHigh) ExeSegment = Segment + (sizeof(DOS_PSP) >> 4);
else ExeSegment = Segment + TotalSize - BaseSize;
/* Copy the program to the code segment */
RtlCopyMemory(SEG_OFF_TO_PTR(ExeSegment, 0),
Address + (Header->e_cparhdr << 4),
min(FileSize - (Header->e_cparhdr << 4),
(ExeSize << 4) - sizeof(DOS_PSP)));
min(FileSize - (Header->e_cparhdr << 4), BaseSize << 4));
/* Get the relocation table */
RelocationTable = (PDWORD)(Address + Header->e_lfarlc);
@ -431,11 +436,11 @@ DWORD DosLoadExecutable(IN DOS_EXEC_TYPE LoadType,
for (i = 0; i < Header->e_crlc; i++)
{
/* Get a pointer to the word that needs to be patched */
RelocWord = (PWORD)SEG_OFF_TO_PTR(Segment + HIWORD(RelocationTable[i]),
0x100 + LOWORD(RelocationTable[i]));
RelocWord = (PWORD)SEG_OFF_TO_PTR(ExeSegment + HIWORD(RelocationTable[i]),
LOWORD(RelocationTable[i]));
/* Add the number of the EXE segment to it */
*RelocWord += Segment + (sizeof(DOS_PSP) >> 4);
*RelocWord += ExeSegment;
}
if (LoadType == DOS_LOAD_AND_EXECUTE)
@ -445,14 +450,13 @@ DWORD DosLoadExecutable(IN DOS_EXEC_TYPE LoadType,
setES(Segment);
/* Set the stack to the location from the header */
setSS(Segment + (sizeof(DOS_PSP) >> 4) + Header->e_ss);
setSS(ExeSegment + Header->e_ss);
setSP(Header->e_sp);
/* Execute */
CurrentPsp = Segment;
DiskTransferArea = MAKELONG(0x80, Segment);
CpuExecute(Segment + Header->e_cs + (sizeof(DOS_PSP) >> 4),
Header->e_ip);
CpuExecute(ExeSegment + Header->e_cs, Header->e_ip);
}
}
else
@ -524,9 +528,6 @@ Cleanup:
if (Segment) DosFreeMemory(Segment);
}
/* Restore the old allocation strategy */
DosAllocStrategy = OldStrategy;
/* Unmap the file*/
if (Address != NULL) UnmapViewOfFile(Address);