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#include <u.h>
#include <libc.h>
#include <mp.h>
#include <libsec.h>
struct th {
char *name;
ulong perm;
ulong size;
char type;
char *user, *group;
};
static char *sndup(char* s, ulong n) {
char *d, *p;
p = memchr(s, 0, n);
if(p)
n = p-s;
d = malloc(n+1);
memcpy(d,s,n);
d[n] = 0;
return d;
}
int readheader(struct th* th) {
int i;
char b[512];
if(readn(0, b, 512) != 512) return -1;
// Check for end of archive
for(i=0; i<512; i++) {
if(b[i]!=0) goto rhok;
}
if(readn(0, b, 512) != 512) return -1;
for(i=0; i<512; i++) {
if(b[i]!=0) return -1;
}
return 0;
rhok:
th->name = cleanname(sndup(b, 100));
th->perm = strtoul(b+100, nil, 8);
th->size = strtoul(b+124, nil, 8);
th->type = b[156];
th->user = sndup(b+265, 32);
th->group= sndup(b+297, 32);
return 1;
}
void main(int argc, char *argv[]) {
ARGBEGIN {
} ARGEND;
for(;;) {
struct th th;
ulong off;
uchar b[512];
char err[ERRMAX];
DigestState *s;
int r, wfd;
r = readheader(&th);
if(r == 0)
exits(nil);
if(r < 0)
sysfatal("unexpected eof");
switch(th.type) {
case '5':
if((wfd = create(th.name, OREAD, DMDIR|th.perm)) >= 0)
close(wfd);
break;
case '0': case 0:
fprint(2, "A %s\n", th.name);
if((wfd = create(th.name, OWRITE|OEXCL, th.perm)) < 0)
sysfatal("%r", th.name);
s = nil;
for(off=0; off<th.size; off+=512) {
if(readn(0, b, 512) == 512){
if((r = th.size-off) > 512)
r = 512;
if(write(wfd, b, r) == r){
s = sha1(b, r, nil, s);
continue;
}
}
errstr(err, sizeof(err));
remove(th.name);
errstr(err, sizeof(err));
sysfatal("%s: %r", th.name);
}
uchar digest[20], hdigest[41];
sha1(nil, 0, digest, s);
enc16((char*)hdigest, 41, digest, 20);
print("%s\t%s\n", th.name, hdigest);
close(wfd);
break;
default:
sysfatal("Unknown file type '%c'", th.type);
}
free(th.name);
free(th.user);
free(th.group);
}
}
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