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- Copy-paste error fix in the initialization of the collating table.
- Fix DosCombineFreeBlocks so that it doesn't say "DOS memory arena corrupted" because while combining blocks, the current block became the last one and we tried to merge it with a next block which, by definition, cannot exist (see comment in the code).
- Remove a spurious call to DosCombineFreeBlocks in DosResizeMemory which was forgotten in r68596.
- Check the validity of the encountered MCBs during the loop for linking or unlinking the UMB chain to the main arena chain.
- Fix the size of the created UMB blocks.

svn path=/trunk/; revision=68606
This commit is contained in:
Hermès Bélusca-Maïto 2015-08-06 23:00:17 +00:00
parent 7da324031a
commit ab22534129
2 changed files with 59 additions and 35 deletions
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4
reactos/subsystems/mvdm/ntvdm/dos/dos32krnl/country.c
View file

@ -279,8 +279,8 @@ BOOLEAN DosCountryInitialize(VOID)
CountryData->FNameTermTbl.Data[21] = ',';
CountryData->CollateTbl.Size = ARRAYSIZE(CountryData->CollateTbl.Data);
for (i = 0; i < CountryData->LoCaseTbl.Size; ++i)
CountryData->LoCaseTbl.Data[i] = i;
for (i = 0; i < CountryData->CollateTbl.Size; ++i)
CountryData->CollateTbl.Data[i] = i;
CountryData->DBCSLeadTbl.Size = 0; // Empty DBCS table
CountryData->DBCSLeadTbl.Data[0] = 0x0000;

90
reactos/subsystems/mvdm/ntvdm/dos/dos32krnl/memory.c
View file

@ -63,7 +63,7 @@ static VOID DosMemValidate(VOID)
/* Make sure it's valid */
if (!ValidateMcb(CurrentMcb))
{
DPRINT1("The DOS memory arena is corrupted! (CurrentMcb = %04x; PreviousMcb = %04X)\n", Segment, PrevSegment);
DPRINT1("The DOS memory arena is corrupted! (CurrentMcb = 0x%04X; PreviousMcb = 0x%04X)\n", Segment, PrevSegment);
return;
}
@ -82,12 +82,25 @@ static VOID DosMemValidate(VOID)
static VOID DosCombineFreeBlocks(WORD StartBlock)
{
/* NOTE: This function is always called with valid MCB blocks */
PDOS_MCB CurrentMcb = SEGMENT_TO_MCB(StartBlock), NextMcb;
/* If this is the last block or it's not free, quit */
if (CurrentMcb->BlockType == 'Z' || CurrentMcb->OwnerPsp != 0) return;
/* If the block is not free, quit */
if (CurrentMcb->OwnerPsp != 0) return;
while (TRUE)
/*
* Loop while the current block is not the last one. It can happen
* that the block is not the last one at the beginning, but becomes
* the last one at the end of the process. This happens in the case
* where its next following blocks are free but not combined yet,
* and they are terminated by a free last block. During the process
* all the blocks are combined together and we end up in the situation
* where the current (free) block is followed by the last (free) block.
* At the last step of the algorithm the current block becomes the
* last one.
*/
while (CurrentMcb->BlockType != 'Z')
{
/* Get a pointer to the next MCB */
NextMcb = SEGMENT_TO_MCB(StartBlock + CurrentMcb->Size + 1);
@ -210,7 +223,6 @@ Next:
}
Done:
DosMemValidate();
/* If we didn't find a free block, bail out */
@ -278,12 +290,11 @@ BOOLEAN DosResizeMemory(WORD BlockData, WORD NewSize, WORD *MaxAvailable)
PDOS_MCB Mcb = SEGMENT_TO_MCB(Segment), NextMcb;
DPRINT("DosResizeMemory: BlockData 0x%04X, NewSize 0x%04X\n",
BlockData,
NewSize);
BlockData, NewSize);
DosMemValidate();
/* Make sure this is a valid, allocated block */
/* Make sure this is a valid and allocated block */
if (BlockData == 0 || !ValidateMcb(Mcb) || Mcb->OwnerPsp == 0)
{
Success = FALSE;
@ -291,15 +302,13 @@ BOOLEAN DosResizeMemory(WORD BlockData, WORD NewSize, WORD *MaxAvailable)
goto Done;
}
DosCombineFreeBlocks(SysVars->FirstMcb);
ReturnSize = Mcb->Size;
/* Check if we need to expand or contract the block */
if (NewSize > Mcb->Size)
{
/* We can't expand the last block */
if (Mcb->BlockType != 'M')
if (Mcb->BlockType == 'Z')
{
Success = FALSE;
goto Done;
@ -431,21 +440,32 @@ BOOLEAN DosLinkUmb(VOID)
DPRINT("Linking UMB\n");
/* Check if UMBs are already linked */
/* Check if UMBs are initialized and already linked */
if (SysVars->UmbChainStart == 0xFFFF) return FALSE;
if (SysVars->UmbLinked) return TRUE;
DosMemValidate();
/* Find the last block */
// FIXME: Use SysVars->UmbChainStart
while ((Mcb->BlockType == 'M') && (Segment <= 0xFFFF))
/* Find the last block before the start of the UMB chain */
while (Segment < SysVars->UmbChainStart)
{
Segment += Mcb->Size + 1;
/* Get a pointer to the MCB */
Mcb = SEGMENT_TO_MCB(Segment);
}
DosMemValidate();
/* Make sure it's valid */
if (!ValidateMcb(Mcb))
{
DPRINT1("The DOS memory arena is corrupted!\n");
Sda->LastErrorCode = ERROR_ARENA_TRASHED;
return FALSE;
}
/* If this was the last MCB in the chain, quit */
if (Mcb->BlockType == 'Z') break;
/* Otherwise, update the segment and continue */
Segment += Mcb->Size + 1;
}
/* Make sure it's valid */
if (Mcb->BlockType != 'Z') return FALSE;
@ -453,6 +473,8 @@ BOOLEAN DosLinkUmb(VOID)
/* Connect the MCB with the UMB chain */
Mcb->BlockType = 'M';
DosMemValidate();
SysVars->UmbLinked = TRUE;
return TRUE;
}
@ -464,25 +486,28 @@ BOOLEAN DosUnlinkUmb(VOID)
DPRINT("Unlinking UMB\n");
/* Check if UMBs are already unlinked */
/* Check if UMBs are initialized and already unlinked */
if (SysVars->UmbChainStart == 0xFFFF) return FALSE;
if (!SysVars->UmbLinked) return TRUE;
DosMemValidate();
/* Find the block preceding the MCB that links it with the UMB chain */
while (Segment <= 0xFFFF)
/* Find the last block before the start of the UMB chain */
while (Segment < SysVars->UmbChainStart)
{
// FIXME: Use SysVars->UmbChainStart
if ((Segment + Mcb->Size) == (SysVars->FirstMcb + USER_MEMORY_SIZE))
/* Get a pointer to the MCB */
Mcb = SEGMENT_TO_MCB(Segment);
/* Make sure it's valid */
if (!ValidateMcb(Mcb))
{
/* This is the last non-UMB segment */
break;
DPRINT1("The DOS memory arena is corrupted!\n");
Sda->LastErrorCode = ERROR_ARENA_TRASHED;
return FALSE;
}
/* Advance to the next MCB */
Segment += Mcb->Size + 1;
Mcb = SEGMENT_TO_MCB(Segment);
}
/* Mark the MCB as the last MCB */
@ -509,7 +534,7 @@ VOID DosChangeMemoryOwner(WORD Segment, WORD NewOwner)
WORD DosGetPreviousUmb(WORD UmbSegment)
{
PDOS_MCB CurrentMcb;
WORD Segment, PrevSegment = 0;
WORD Segment, PrevSegment = 0; // FIXME: or use UmbChainStart ??
if (SysVars->UmbChainStart == 0xFFFF)
return 0;
@ -529,14 +554,13 @@ WORD DosGetPreviousUmb(WORD UmbSegment)
return 0;
}
if (Segment >= UmbSegment)
break;
/* We went over the UMB segment, quit */
if (Segment >= UmbSegment) break;
PrevSegment = Segment;
/* If this was the last MCB in the chain, quit */
if (CurrentMcb->BlockType == 'Z')
break;
if (CurrentMcb->BlockType == 'Z') break;
/* Otherwise, update the segment and continue */
Segment += CurrentMcb->Size + 1;
@ -583,7 +607,7 @@ VOID DosInitializeUmb(VOID)
// It will be splitted as needed just below.
Mcb = SEGMENT_TO_MCB(SysVars->FirstMcb + USER_MEMORY_SIZE + 1); // '+1': Readjust the fact that USER_MEMORY_SIZE is based using 0x9FFE instead of 0x9FFF
Mcb->BlockType = 'Z'; // At the moment it is really the last block
Mcb->Size = SysVars->UmbChainStart /* UmbSegment */ - SysVars->FirstMcb - USER_MEMORY_SIZE - 2;
Mcb->Size = (SysVars->UmbChainStart /* UmbSegment */ - SysVars->FirstMcb - USER_MEMORY_SIZE - 2) + 1;
Mcb->OwnerPsp = SYSTEM_PSP;
RtlCopyMemory(Mcb->Name, "SC ", sizeof("SC ")-1);
@ -609,7 +633,7 @@ VOID DosInitializeUmb(VOID)
Mcb = SEGMENT_TO_MCB(UmbSegment + /*Mcb->Size*/(Size - 1) + 0);
// Mcb->BlockType = 'Z'; // FIXME: What if this block happens to be the last one??
Mcb->BlockType = PrevMcb->BlockType;
Mcb->Size = PrevMcb->Size - (UmbSegment + Size - PrevSegment);
Mcb->Size = PrevMcb->Size - (UmbSegment + Size - PrevSegment) + 1;
Mcb->OwnerPsp = PrevMcb->OwnerPsp;
RtlCopyMemory(Mcb->Name, PrevMcb->Name, sizeof(PrevMcb->Name));