| 1 | #include <fcntl.h> |
| 2 | #include <sys/ioctl.h> |
| 3 | #include <sys/param.h> |
| 4 | #include <sys/types.h> |
| 5 | #include <stdlib.h> |
| 6 | #include <termios.h> |
| 7 | #include <unistd.h> |
| 8 | |
| 9 | |
| 10 | int openpty(int* amaster, int* aslave, char* name, struct termios* termp, struct winsize* winp) |
| 11 | { |
| 12 | char buf[512]; |
| 13 | |
| 14 | int master = open("/dev/ptmx", O_RDWR); |
| 15 | if (master == -1) return -1; |
| 16 | if (grantpt(master) || unlockpt(master) || ptsname_r(master, buf, sizeof buf)) goto fail; |
| 17 | |
| 18 | int slave = open(buf, O_RDWR | O_NOCTTY); |
| 19 | if (slave == -1) goto fail; |
| 20 | |
| 21 | /* XXX Should we ignore errors here? */ |
| 22 | if (termp) tcsetattr(slave, TCSAFLUSH, termp); |
| 23 | if (winp) ioctl(slave, TIOCSWINSZ, winp); |
| 24 | |
| 25 | *amaster = master; |
| 26 | *aslave = slave; |
| 27 | if (name != NULL) strcpy(name, buf); |
| 28 | return 0; |
| 29 | |
| 30 | fail: |
| 31 | close(master); |
| 32 | return -1; |
| 33 | } |
| 34 | |
| 35 | |
| 36 | int login_tty(int fd) |
| 37 | { |
| 38 | setsid(); |
| 39 | if (ioctl(fd, TIOCSCTTY, NULL) == -1) return -1; |
| 40 | dup2(fd, 0); |
| 41 | dup2(fd, 1); |
| 42 | dup2(fd, 2); |
| 43 | if (fd > 2) close(fd); |
| 44 | return 0; |
| 45 | } |
| 46 | |
| 47 | |
| 48 | int forkpty(int* amaster, char* name, struct termios* termp, struct winsize* winp) |
| 49 | { |
| 50 | int master, slave; |
| 51 | if (openpty(&master, &slave, name, termp, winp) == -1) { |
| 52 | return -1; |
| 53 | } |
| 54 | |
| 55 | int pid; |
| 56 | switch (pid = fork()) { |
| 57 | case -1: |
| 58 | return -1; |
| 59 | case 0: |
| 60 | close(master); |
| 61 | if (login_tty(slave)) _exit(1); |
| 62 | return 0; |
| 63 | default: |
| 64 | *amaster = master; |
| 65 | close (slave); |
| 66 | return pid; |
| 67 | } |
| 68 | } |