1992/0612/port/malloc.c (diff list | history)

1992/0612/sys/src/9/port/malloc.c:4,10 – 1992/0618/sys/src/9/port/malloc.c:4,10 (short | long | prev | next)
1992/0612		enum { MAGIC = 0xDEADBABE, MAX2SIZE = 20
1992/0618		MAXPOW = 20
1992/0612		};
1990/1210
1992/0612		typedef struct Bucket Bucket;
1992/0612/sys/src/9/port/malloc.c:20,28 – 1992/0618/sys/src/9/port/malloc.c:20,27
1992/0612		struct Arena
1990/1210		{
1992/0612		Lock; Bucket *btab[MAX2SIZE];
1992/0618		Bucket *btab[MAXPOW];
1992/0612		};
1990/1210
1992/0612		static Arena arena; #define datoff ((int)&((Bucket*)0)->data)
1990/1210
1992/0612/sys/src/9/port/malloc.c:32,45 – 1992/0618/sys/src/9/port/malloc.c:31,45
1992/0612		int pow; Bucket *bp;
1990/1210
1992/0612		for(pow = 1; pow < MAX2SIZE; pow++) {
1992/0618		size += sizeof(Bucket); for(pow = 1; pow < MAXPOW; pow++)
1992/0612		if(size <= (1<<pow)) goto good;
1990/1210		}
1992/0612		return nil;
1992/0618		return 0;
1992/0612		good: /* Allocate off this list */ lock(&arena); bp = arena.btab[pow]; if(bp) {
1992/0612/sys/src/9/port/malloc.c:47,53 – 1992/0618/sys/src/9/port/malloc.c:47,53
1992/0612		arena.unlock();
1990/1210
1992/0612		if(bp->magic != 0) abort();
1992/0618		panic("malloc");
1990/1210
1992/0612		bp->magic = MAGIC;
1990/1210
1992/0612/sys/src/9/port/malloc.c:55,68 – 1992/0618/sys/src/9/port/malloc.c:55,67
1992/0612		return bp->data;
1990/1210		}
1992/0612		unlock(&arena);
1992/0618
1992/0612		size = sizeof(Bucket)+(1<<pow); bp = sbrk(size);
1992/0618		bp = xbrk(size);
1992/0612		if((int)bp < 0) return nil;
1990/1210
1992/0612		bp->size = pow; bp->magic = MAGIC;
1990/1210
1992/0618		memset(bp->data, 0, size);
1992/0612		return bp->data;
1990/1210		}