ref: 04c4a9ca8b06e34a203f7ddacc2263cf2077e1aa
dir: /sys/src/cmd/hgfs/hash.c/
#include <u.h> #include <libc.h> #include <thread.h> #include "dat.h" #include "fns.h" #include <mp.h> #include <libsec.h> int Hfmt(Fmt *f) { uchar *p, *e; for(p = va_arg(f->args, uchar*), e = p + HASHSZ; p != e; p++) if(fmtprint(f, "%.2x", *p) < 0) return -1; return 0; } int fhash(int fd, uchar p1[], uchar p2[], uchar h[]) { DigestState *ds; uchar buf[BUFSZ]; int n; ds = nil; memset(h, 0, HASHSZ); if(memcmp(p1, p2, HASHSZ) > 0){ ds = sha1(p2, HASHSZ, nil, ds); sha1(p1, HASHSZ, nil, ds); } else { ds = sha1(p1, HASHSZ, nil, ds); sha1(p2, HASHSZ, nil, ds); } while((n = read(fd, buf, BUFSZ)) > 0) sha1(buf, n, nil, ds); sha1(buf, 0, h, ds); return 0; } int hex2hash(char *s, uchar *h) { uchar *b; int n; b = h; memset(h, 0, HASHSZ); n = HASHSZ*2; while(*s && n > 0){ if(*s >= '0' && *s <= '9') *h |= *s - '0'; else if(*s >= 'a' && *s <= 'f') *h |= 10 + *s - 'a'; else if(*s >= 'A' && *s <= 'F') *h |= 10 + *s - 'A'; else break; if(n-- & 1) h++; else *h <<= 4; s++; } return h - b; } uvlong hash2qid(uchar *h) { uvlong v; int i; v = 0; for(i=0; i<8; i++) v |= (uvlong)h[i]<<(56-8*i); return v; } int readhash(char *path, char *name, uchar hash[]) { char buf[MAXPATH], *p; int n; snprint(buf, sizeof(buf), "%s/%s", path, name); readfile(buf, buf, sizeof(buf)); if(p = strchr(buf, '.')) p++; else p = buf; n = hex2hash(p, hash); if(n != HASHSZ) return -1; return 0; }