1 #include "stdinc.h"
2 #include "dat.h"
3 #include "fns.h"
4 
5 void
6 fmtzbinit(Fmt *f, ZBlock *b)
7 {
8 	f->runes = 0;
9 	f->start = b->data;
10 	f->to = f->start;
11 	f->stop = (char*)f->start + b->len;
12 	f->flush = nil;
13 	f->farg = nil;
14 	f->nfmt = 0;
15 }
16 
17 #define ROUNDUP(p, n) ((void*)(((uintptr)(p)+(n)-1)&~(uintptr)((n)-1)))
18 
19 static char zmagic[] = "1234567890abcdefghijkl";
20 
21 ZBlock *
22 alloczblock(u32int size, int zeroed, uint blocksize)
23 {
24 	uchar *p, *data;
25 	ZBlock *b;
26 	static ZBlock z;
27 	int n;
28 
29 	if(blocksize == 0)
30 		blocksize = 32;	/* try for cache line alignment */
31 
32 	n = size+32/*XXX*/+sizeof(ZBlock)+blocksize+8;
33 	p = malloc(n);
34 	if(p == nil){
35 		seterr(EOk, "out of memory");
36 		return nil;
37 	}
38 
39 	data = ROUNDUP(p, blocksize);
40 	b = ROUNDUP(data+size+32/*XXX*/, 8);
41 	if(0) fprint(2, "alloc %p-%p data %p-%p b %p-%p\n",
42 		p, p+n, data, data+size, b, b+1);
43 	*b = z;
44 	b->data = data;
45 	b->free = p;
46 	b->len = size;
47 	b->_size = size;
48 	if(zeroed)
49 		memset(b->data, 0, size);
50 	memmove(b->data+size, zmagic, 32/*XXX*/);
51 	return b;
52 }
53 
54 void
55 freezblock(ZBlock *b)
56 {
57 	if(b){
58 		if(memcmp(b->data+b->_size, zmagic, 32) != 0)
59 			abort();
60 		memset(b->data+b->_size, 0, 32);
61 		free(b->free);
62 	}
63 }
64 
65 ZBlock*
66 packet2zblock(Packet *p, u32int size)
67 {
68 	ZBlock *b;
69 
70 	if(p == nil)
71 		return nil;
72 	b = alloczblock(size, 0, 0);
73 	if(b == nil)
74 		return nil;
75 	if(packetcopy(p, b->data, 0, size) < 0){
76 		freezblock(b);
77 		return nil;
78 	}
79 	return b;
80 }
81 
82 Packet*
83 zblock2packet(ZBlock *zb, u32int size)
84 {
85 	Packet *p;
86 
87 	if(zb == nil)
88 		return nil;
89 	p = packetalloc();
90 	packetappend(p, zb->data, size);
91 	return p;
92 }
93