1 74f990ad 2003-11-23 devnull #include <u.h>
  2 74f990ad 2003-11-23 devnull #include <libc.h>
  3 74f990ad 2003-11-23 devnull #include <bin.h>
  4 74f990ad 2003-11-23 devnull 
  5 74f990ad 2003-11-23 devnull enum
  6 74f990ad 2003-11-23 devnull {
  7 74f990ad 2003-11-23 devnull 	StructAlign = sizeof(union {vlong vl; double d; ulong p; void *v;
  8 74f990ad 2003-11-23 devnull 				struct{vlong v;}vs; struct{double d;}ds; struct{ulong p;}ss; struct{void *v;}xs;})
  9 74f990ad 2003-11-23 devnull };
 10 74f990ad 2003-11-23 devnull 
 11 74f990ad 2003-11-23 devnull enum
 12 74f990ad 2003-11-23 devnull {
 13 74f990ad 2003-11-23 devnull 	BinSize	= 8*1024
 14 74f990ad 2003-11-23 devnull };
 15 74f990ad 2003-11-23 devnull 
 16 74f990ad 2003-11-23 devnull struct Bin
 17 74f990ad 2003-11-23 devnull {
 18 74f990ad 2003-11-23 devnull 	Bin	*next;
 19 74f990ad 2003-11-23 devnull 	ulong	total;			/* total bytes allocated in can->next */
 20 74f990ad 2003-11-23 devnull 	ulong	pos;
 21 74f990ad 2003-11-23 devnull 	ulong	end;
 22 74f990ad 2003-11-23 devnull 	ulong	v;			/* last value allocated */
 23 74f990ad 2003-11-23 devnull 	uchar	body[BinSize];
 24 74f990ad 2003-11-23 devnull };
 25 74f990ad 2003-11-23 devnull 
 26 74f990ad 2003-11-23 devnull /*
 27 74f990ad 2003-11-23 devnull  * allocator which allows an entire set to be freed at one time
 28 74f990ad 2003-11-23 devnull  */
 29 74f990ad 2003-11-23 devnull static Bin*
 30 74f990ad 2003-11-23 devnull mkbin(Bin *bin, ulong size)
 31 74f990ad 2003-11-23 devnull {
 32 74f990ad 2003-11-23 devnull 	Bin *b;
 33 74f990ad 2003-11-23 devnull 
 34 74f990ad 2003-11-23 devnull 	size = ((size << 1) + (BinSize - 1)) & ~(BinSize - 1);
 35 74f990ad 2003-11-23 devnull 	b = malloc(sizeof(Bin) + size - BinSize);
 36 74f990ad 2003-11-23 devnull 	if(b == nil)
 37 74f990ad 2003-11-23 devnull 		return nil;
 38 74f990ad 2003-11-23 devnull 	b->next = bin;
 39 74f990ad 2003-11-23 devnull 	b->total = 0;
 40 74f990ad 2003-11-23 devnull 	if(bin != nil)
 41 74f990ad 2003-11-23 devnull 		b->total = bin->total + bin->pos - (ulong)bin->body;
 42 74f990ad 2003-11-23 devnull 	b->pos = (ulong)b->body;
 43 74f990ad 2003-11-23 devnull 	b->end = b->pos + size;
 44 74f990ad 2003-11-23 devnull 	return b;
 45 74f990ad 2003-11-23 devnull }
 46 74f990ad 2003-11-23 devnull 
 47 74f990ad 2003-11-23 devnull void*
 48 74f990ad 2003-11-23 devnull binalloc(Bin **bin, ulong size, int zero)
 49 74f990ad 2003-11-23 devnull {
 50 74f990ad 2003-11-23 devnull 	Bin *b;
 51 74f990ad 2003-11-23 devnull 	ulong p;
 52 74f990ad 2003-11-23 devnull 
 53 74f990ad 2003-11-23 devnull 	if(size == 0)
 54 74f990ad 2003-11-23 devnull 		size = 1;
 55 74f990ad 2003-11-23 devnull 	b = *bin;
 56 74f990ad 2003-11-23 devnull 	if(b == nil){
 57 74f990ad 2003-11-23 devnull 		b = mkbin(nil, size);
 58 74f990ad 2003-11-23 devnull 		if(b == nil)
 59 74f990ad 2003-11-23 devnull 			return nil;
 60 74f990ad 2003-11-23 devnull 		*bin = b;
 61 74f990ad 2003-11-23 devnull 	}
 62 74f990ad 2003-11-23 devnull 	p = b->pos;
 63 74f990ad 2003-11-23 devnull 	p = (p + (StructAlign - 1)) & ~(StructAlign - 1);
 64 74f990ad 2003-11-23 devnull 	if(p + size > b->end){
 65 74f990ad 2003-11-23 devnull 		b = mkbin(b, size);
 66 74f990ad 2003-11-23 devnull 		if(b == nil)
 67 74f990ad 2003-11-23 devnull 			return nil;
 68 74f990ad 2003-11-23 devnull 		*bin = b;
 69 74f990ad 2003-11-23 devnull 		p = b->pos;
 70 74f990ad 2003-11-23 devnull 	}
 71 74f990ad 2003-11-23 devnull 	b->pos = p + size;
 72 74f990ad 2003-11-23 devnull 	b->v = p;
 73 74f990ad 2003-11-23 devnull 	if(zero)
 74 74f990ad 2003-11-23 devnull 		memset((void*)p, 0, size);
 75 74f990ad 2003-11-23 devnull 	return (void*)p;
 76 74f990ad 2003-11-23 devnull }
 77 74f990ad 2003-11-23 devnull 
 78 74f990ad 2003-11-23 devnull void*
 79 74f990ad 2003-11-23 devnull bingrow(Bin **bin, void *op, ulong osize, ulong size, int zero)
 80 74f990ad 2003-11-23 devnull {
 81 74f990ad 2003-11-23 devnull 	Bin *b;
 82 74f990ad 2003-11-23 devnull 	void *np;
 83 74f990ad 2003-11-23 devnull 	ulong p;
 84 74f990ad 2003-11-23 devnull 
 85 74f990ad 2003-11-23 devnull 	p = (ulong)op;
 86 74f990ad 2003-11-23 devnull 	b = *bin;
 87 74f990ad 2003-11-23 devnull 	if(b != nil && p == b->v && p + size <= b->end){
 88 74f990ad 2003-11-23 devnull 		b->pos = p + size;
 89 74f990ad 2003-11-23 devnull 		if(zero)
 90 74f990ad 2003-11-23 devnull 			memset((char*)p + osize, 0, size - osize);
 91 74f990ad 2003-11-23 devnull 		return op;
 92 74f990ad 2003-11-23 devnull 	}
 93 74f990ad 2003-11-23 devnull 	np = binalloc(bin, size, zero);
 94 74f990ad 2003-11-23 devnull 	if(np == nil)
 95 74f990ad 2003-11-23 devnull 		return nil;
 96 74f990ad 2003-11-23 devnull 	memmove(np, op, osize);
 97 74f990ad 2003-11-23 devnull 	return np;
 98 74f990ad 2003-11-23 devnull }
 99 74f990ad 2003-11-23 devnull 
100 74f990ad 2003-11-23 devnull void
101 74f990ad 2003-11-23 devnull binfree(Bin **bin)
102 74f990ad 2003-11-23 devnull {
103 74f990ad 2003-11-23 devnull 	Bin *last;
104 74f990ad 2003-11-23 devnull 
105 74f990ad 2003-11-23 devnull 	while(*bin != nil){
106 74f990ad 2003-11-23 devnull 		last = *bin;
107 74f990ad 2003-11-23 devnull 		*bin = (*bin)->next;
108 74f990ad 2003-11-23 devnull 		last->pos = (ulong)last->body;
109 74f990ad 2003-11-23 devnull 		free(last);
110 74f990ad 2003-11-23 devnull 	}
111 74f990ad 2003-11-23 devnull }