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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(int fd, struct th* th) {
int i;
char b[512];
if(readn(fd, b, 512) != 512) return -1;
// Check for end of archive
for(i=0; i<512; i++) {
if(b[i]!=0) goto rhok;
}
if(readn(fd, b, 512) != 512) return -1;
for(i=0; i<512; i++) {
if(b[i]!=0) return -1;
}
return 0;
rhok:
th->name = 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;
}
int main(void) {
while(1) {
struct th th;
ulong off;
uchar b[512];
DigestState *s;
int wfd;
int r = readheader(0, &th);
if(r <= 0) return r;
switch(th.type) {
case '5':
create(th.name, OREAD, DMDIR|th.perm);
break;
case '0': case 0:
print("A %s\n", th.name);
r = access(th.name, 0);
if(r == 0) {
print("File already exists: %s\n", th.name);
return -1;
}
if((wfd = create(th.name, OWRITE, th.perm)) < 0) {
print("Create failed: %s\n", th.name);
return -1;
}
s = nil;
for(off=0; off<th.size; off+=512) {
int n = th.size-off;
n = n<512 ? n : 512;
if(readn(0, b, 512) != 512) return -1;
if(write(wfd, b, n) != n) return -1;
s = sha1(b, n, nil, s);
}
uchar digest[20], hdigest[41];
sha1(nil, 0, digest, s);
enc16((char*)hdigest, 41, digest, 20);
fprint(2, "%s\t%s\n", th.name, hdigest);
close(wfd);
break;
default:
print("Unknown file type '%c'\n", th.type);
return -1;
}
free(th.name);
free(th.user);
free(th.group);
}
}
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