1 #include "stdinc.h"
2 #include "dat.h"
3 #include "fns.h"
4 
5 static int verbose, quiet;
6 
7 void
8 usage(void)
9 {
10 	fprint(2, "usage: rdarena [-qv] arenapart arena\n");
11 	threadexitsall(0);
12 }
13 
14 static void
15 rdarena(Arena *arena)
16 {
17 	ZBlock *b;
18 	u64int a, e;
19 	u32int bs;
20 
21 	if (!quiet) {
22 		fprint(2, "copying %s to standard output\n", arena->name);
23 		printarena(2, arena);
24 	}
25 
26 	bs = MaxIoSize;
27 	if(bs < arena->blocksize)
28 		bs = arena->blocksize;
29 
30 	b = alloczblock(bs, 0, arena->blocksize);
31 	e = arena->base + arena->size + arena->blocksize;
32 	for(a = arena->base - arena->blocksize; a + arena->blocksize <= e; a += bs){
33 		if(a + bs > e)
34 			bs = arena->blocksize;
35 		if(readpart(arena->part, a, b->data, bs) < 0)
36 			fprint(2, "can't copy %s, read at %lld failed: %r\n", arena->name, a);
37 		if(write(1, b->data, bs) != bs)
38 			sysfatal("can't copy %s, write at %lld failed: %r", arena->name, a);
39 	}
40 
41 	freezblock(b);
42 }
43 
44 void
45 threadmain(int argc, char *argv[])
46 {
47 	ArenaPart *ap;
48 	Part *part;
49 	char *file, *aname;
50 	int i;
51 
52 	ventifmtinstall();
53 	statsinit();
54 
55 	ARGBEGIN{
56 	case 'q':
57 		quiet++;
58 		break;
59 	case 'v':
60 		verbose++;
61 		break;
62 	default:
63 		usage();
64 		break;
65 	}ARGEND
66 
67 	readonly = 1;
68 
69 	if(argc != 2)
70 		usage();
71 
72 	file = argv[0];
73 	aname = argv[1];
74 
75 	part = initpart(file, OREAD|ODIRECT);
76 	if(part == nil)
77 		sysfatal("can't open partition %s: %r", file);
78 
79 	ap = initarenapart(part);
80 	if(ap == nil)
81 		sysfatal("can't initialize arena partition in %s: %r", file);
82 
83 	if(verbose)
84 		printarenapart(2, ap);
85 
86 	initdcache(8 * MaxDiskBlock);
87 
88 	for(i = 0; i < ap->narenas; i++){
89 		if(strcmp(ap->arenas[i]->name, aname) == 0){
90 			rdarena(ap->arenas[i]);
91 			threadexitsall(0);
92 		}
93 	}
94 
95 	sysfatal("couldn't find arena %s", aname);
96 }