1 /* microcom.c - Simple serial console. 2 * 3 * Copyright 2017 The Android Open Source Project. 4 5 USE_MICROCOM(NEWTOY(microcom, "<1>1s:X", TOYFLAG_USR|TOYFLAG_BIN)) 6 7 config MICROCOM 8 bool "microcom" 9 default y 10 help 11 usage: microcom [-s SPEED] [-X] DEVICE 12 13 Simple serial console. 14 15 -s Set baud rate to SPEED 16 -X Ignore ^@ (send break) and ^] (exit) 17 */ 18 19 #define FOR_microcom 20 #include "toys.h" 21 22 GLOBALS( 23 char *s; 24 25 int fd; 26 struct termios original_stdin_state, original_fd_state; 27 ) 28 29 // TODO: tty_sigreset outputs ansi escape sequences, how to disable? 30 static void restore_states(int i) 31 { 32 tcsetattr(0, TCSAFLUSH, &TT.original_stdin_state); 33 tcsetattr(TT.fd, TCSAFLUSH, &TT.original_fd_state); 34 } 35 36 void microcom_main(void) 37 { 38 struct pollfd fds[2]; 39 int i, speed; 40 41 if (!TT.s) speed = 115200; 42 else speed = atoi(TT.s); 43 44 // Open with O_NDELAY, but switch back to blocking for reads. 45 TT.fd = xopen(*toys.optargs, O_RDWR | O_NOCTTY | O_NDELAY); 46 if (-1==(i = fcntl(TT.fd, F_GETFL, 0)) || fcntl(TT.fd, F_SETFL, i&~O_NDELAY)) 47 perror_exit_raw(*toys.optargs); 48 49 // Set both input and output to raw mode. 50 xset_terminal(TT.fd, 1, speed, &TT.original_fd_state); 51 set_terminal(0, 1, 0, &TT.original_stdin_state); 52 // ...and arrange to restore things, however we may exit. 53 sigatexit(restore_states); 54 55 fds[0].fd = TT.fd; 56 fds[0].events = POLLIN; 57 fds[1].fd = 0; 58 fds[1].events = POLLIN; 59 60 while (poll(fds, 2, -1) > 0) { 61 char buf[BUFSIZ]; 62 63 // Read from connection, write to stdout. 64 if (fds[0].revents) { 65 ssize_t n = read(TT.fd, buf, sizeof(buf)); 66 if (n > 0) xwrite(0, buf, n); 67 else break; 68 } 69 70 // Read from stdin, write to connection. 71 if (fds[1].revents) { 72 if (read(0, buf, 1) != 1) break; 73 if (!(toys.optflags & FLAG_X)) { 74 if (!*buf) { 75 tcsendbreak(TT.fd, 0); 76 continue; 77 } else if (*buf == (']'-'@')) break; 78 } 79 xwrite(TT.fd, buf, 1); 80 } 81 } 82 } 83
