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Improve assertions in malloc. 

This also uses the user-space available <assert.h> header.
This commit is contained in:
Jonas 'Sortie' Termansen 2012-09-07 21:46:43 +02:00
parent 2158a16904
commit 2135a2d432
1 changed files with 32 additions and 1 deletions
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33
libmaxsi/heap.cpp
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@ -32,7 +32,12 @@
#endif
#ifndef SORTIX_KERNEL
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#undef ASSERT
#define ASSERT(invariant) assert(invariant)
#endif
#define PARANOIA 1
@ -231,6 +236,20 @@ namespace Maxsi
// Bit N is set if bin[N] contains a chunk.
size_t bincontainschunks;
static bool IsGoodHeapPointer(void* ptr, size_t size)
{
uintptr_t ptrlower = (uintptr_t) ptr;
uintptr_t ptrupper = ptrlower + size;
#ifdef HEAP_GROWS_DOWNWARDS
uintptr_t heaplower = wilderness;
uintptr_t heapupper = heapstart;
#else
uintptr_t heaplower = heapstart;
uintptr_t heapupper = wilderness;
#endif
return heaplower <= ptrlower && ptrupper <= heapupper;
}
// A preamble to every chunk providing meta-information.
struct Chunk
{
@ -301,9 +320,13 @@ namespace Maxsi
bool Chunk::IsSane()
{
if ( !IsGoodHeapPointer(this, sizeof(*this)) )
return false;
if ( !size ) { return false; }
size_t binindex = BSR(size);
Trailer* trailer = GetTrailer();
if ( !IsGoodHeapPointer(trailer, sizeof(*trailer)) )
return false;
if ( trailer->size != size ) { return false; }
if ( IsUsed() )
{
@ -314,10 +337,16 @@ namespace Maxsi
{
if ( ((addr_t) nextunused) & (ALIGNMENT-1UL) ) { return false; }
if ( ((addr_t) trailer->prevunused) & (ALIGNMENT-1UL) ) { return false; }
if ( nextunused && !IsGoodHeapPointer(nextunused->GetTrailer(),
sizeof(Trailer)) )
return false;
if ( nextunused && nextunused->GetTrailer()->prevunused != this ) { return false; }
if ( trailer->prevunused )
{
if ( !IsGoodHeapPointer(trailer->prevunused,
sizeof(*trailer->prevunused)) )
return false;
if ( bins[binindex] == this ) { return false; }
if ( trailer->prevunused->nextunused != this ) { return false; }
}
@ -530,10 +559,13 @@ namespace Maxsi
#else
Chunk* chunk = (Chunk*) (wilderness - wildernesssize);
#endif
ASSERT(size <= wildernesssize);
wildernesssize -= size;
heapsize += size;
ASSERT(IsGoodHeapPointer(chunk, sizeof(*chunk)));
chunk->size = size;
Trailer* trailer = chunk->GetTrailer();
ASSERT(IsGoodHeapPointer(trailer, sizeof(*trailer)));
trailer->size = size;
chunk->magic = MAGIC;
trailer->magic = MAGIC;
@ -634,7 +666,6 @@ namespace Maxsi
#endif
if ( !addr) { return; }
Chunk* chunk = (Chunk*) ((addr_t) addr - sizeof(Chunk));
ASSERT(chunk->IsUsed());
ASSERT(chunk->IsSane());