xfnw/plan9fox
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

pool: more strict checktree() for poolcheck

Browse source 
check that Free.next and Free.prev pointers are not nil.

check that Free.left and Free.right are Poison in non-tree nodes.

check that Free.left and Free.right are *not* Poison in tree nodes.

change Poison to 0xffffffffcafebabe for 64bit machines.
This commit is contained in:
cinap_lenrek 2015-01-05 14:23:01 +01:00
parent 384d4d2d62
commit ef9c5b4cc7
1 changed files with 10 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

18
sys/src/libc/port/pool.c
View file

@ -123,7 +123,7 @@ enum {
static uchar datamagic[] = { 0xFE, 0xF1, 0xF0, 0xFA };
#define Poison (void*)0xCafeBabe
#define Poison ((void*)-0x35014542) /* cafebabe */
#define _B2D(a) ((void*)((uchar*)a+sizeof(Bhdr)))
#define _D2B(v) ((Alloc*)((uchar*)v-sizeof(Bhdr)))
@ -197,12 +197,12 @@ checklist(Free *t)
Free *q;
for(q=t->next; q!=t; q=q->next){
assert(q->size == t->size);
assert(q->next==nil || q->next->prev==q);
assert(q->prev==nil || q->prev->next==q);
// assert(q->left==nil);
// assert(q->right==nil);
assert(q->magic==FREE_MAGIC);
assert(q->size==t->size);
assert(q->left==Poison);
assert(q->right==Poison);
assert(q->next!=nil && q->next!=Poison && q->next->prev==q);
assert(q->prev!=nil && q->prev!=Poison && q->prev->next==q);
}
}
@ -211,8 +211,10 @@ checktree(Free *t, int a, int b)
{
assert(t->magic==FREE_MAGIC);
assert(a < t->size && t->size < b);
assert(t->next==nil || t->next->prev==t);
assert(t->prev==nil || t->prev->next==t);
assert(t->left!=Poison);
assert(t->right!=Poison);
assert(t->next!=nil && t->next!=Poison && t->next->prev==t);
assert(t->prev!=nil && t->prev!=Poison && t->prev->next==t);
checklist(t);
if(t->left)
checktree(t->left, a, t->size);