rdarena.c (1693B)
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 }