1*c9945492SAndroid Build Coastguard Worker #include <unistd.h>
2*c9945492SAndroid Build Coastguard Worker #include <errno.h>
3*c9945492SAndroid Build Coastguard Worker #include <sys/stat.h>
4*c9945492SAndroid Build Coastguard Worker #include "syscall.h"
5*c9945492SAndroid Build Coastguard Worker
ttyname_r(int fd,char * name,size_t size)6*c9945492SAndroid Build Coastguard Worker int ttyname_r(int fd, char *name, size_t size)
7*c9945492SAndroid Build Coastguard Worker {
8*c9945492SAndroid Build Coastguard Worker struct stat st1, st2;
9*c9945492SAndroid Build Coastguard Worker char procname[sizeof "/proc/self/fd/" + 3*sizeof(int) + 2];
10*c9945492SAndroid Build Coastguard Worker ssize_t l;
11*c9945492SAndroid Build Coastguard Worker
12*c9945492SAndroid Build Coastguard Worker if (!isatty(fd)) return errno;
13*c9945492SAndroid Build Coastguard Worker
14*c9945492SAndroid Build Coastguard Worker __procfdname(procname, fd);
15*c9945492SAndroid Build Coastguard Worker l = readlink(procname, name, size);
16*c9945492SAndroid Build Coastguard Worker
17*c9945492SAndroid Build Coastguard Worker if (l < 0) return errno;
18*c9945492SAndroid Build Coastguard Worker else if (l == size) return ERANGE;
19*c9945492SAndroid Build Coastguard Worker
20*c9945492SAndroid Build Coastguard Worker name[l] = 0;
21*c9945492SAndroid Build Coastguard Worker
22*c9945492SAndroid Build Coastguard Worker if (stat(name, &st1) || fstat(fd, &st2))
23*c9945492SAndroid Build Coastguard Worker return errno;
24*c9945492SAndroid Build Coastguard Worker if (st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino)
25*c9945492SAndroid Build Coastguard Worker return ENODEV;
26*c9945492SAndroid Build Coastguard Worker
27*c9945492SAndroid Build Coastguard Worker return 0;
28*c9945492SAndroid Build Coastguard Worker }
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