tools/kvm/term.c

   1 #include <poll.h>
   2 #include <stdbool.h>
   3 #include <termios.h>
   4 #include <stdio.h>
   5 #include <unistd.h>
   6 #include <sys/uio.h>
   7 #include <signal.h>
   8
   9 #include "kvm/read-write.h"
  10 #include "kvm/term.h"
  11 #include "kvm/util.h"
  12 #include "kvm/kvm.h"
  13 #include "kvm/kvm-cpu.h"
  14
  15 extern struct kvm *kvm;
  16 static struct termios   orig_term;
  17
  18 int term_escape_char    = 0x01; /* ctrl-a is used for escape */
  19 bool term_got_escape    = false;
  20
  21 int active_console;
  22
  23 int term_getc(int who)
  24 {
  25         int c;
  26
  27         if (who != active_console)
  28                 return -1;
  29
  30         if (read_in_full(STDIN_FILENO, &c, 1) < 0)
  31                 return -1;
  32
  33         c &= 0xff;
  34
  35         if (term_got_escape) {
  36                 term_got_escape = false;
  37                 if (c == 'x')
  38                         kvm_cpu__reboot();
  39                 if (c == term_escape_char)
  40                         return c;
  41         }
  42
  43         if (c == term_escape_char) {
  44                 term_got_escape = true;
  45                 return -1;
  46         }
  47
  48         return c;
  49 }
  50
  51 int term_putc(int who, char *addr, int cnt)
  52 {
  53         if (who != active_console)
  54                 return -1;
  55
  56         while (cnt--)
  57                 fprintf(stdout, "%c", *addr++);
  58
  59         fflush(stdout);
  60         return cnt;
  61 }
  62
  63 int term_getc_iov(int who, struct iovec *iov, int iovcnt)
  64 {
  65         int c;
  66
  67         if (who != active_console)
  68                 return 0;
  69
  70         c = term_getc(who);
  71
  72         if (c < 0)
  73                 return 0;
  74
  75         *((int *)iov[0].iov_base)       = c;
  76
  77         return sizeof(char);
  78 }
  79
  80 int term_putc_iov(int who, struct iovec *iov, int iovcnt)
  81 {
  82         if (who != active_console)
  83                 return 0;
  84
  85         return writev(STDOUT_FILENO, iov, iovcnt);
  86 }
  87
  88 bool term_readable(int who)
  89 {
  90         struct pollfd pollfd = (struct pollfd) {
  91                 .fd     = STDIN_FILENO,
  92                 .events = POLLIN,
  93                 .revents = 0,
  94         };
  95
  96         if (who != active_console)
  97                 return false;
  98
  99         return poll(&pollfd, 1, 0) > 0;
 100 }
 101
 102 static void term_cleanup(void)
 103 {
 104         tcsetattr(STDIN_FILENO, TCSANOW, &orig_term);
 105 }
 106
 107 static void term_sig_cleanup(int sig)
 108 {
 109         term_cleanup();
 110         signal(sig, SIG_DFL);
 111         raise(sig);
 112 }
 113
 114 void term_init(void)
 115 {
 116         struct termios term;
 117
 118         if (tcgetattr(STDIN_FILENO, &orig_term) < 0)
 119                 die("unable to save initial standard input settings");
 120
 121         term = orig_term;
 122         term.c_lflag &= ~(ICANON | ECHO | ISIG);
 123         tcsetattr(STDIN_FILENO, TCSANOW, &term);
 124
 125         signal(SIGTERM, term_sig_cleanup);
 126         atexit(term_cleanup);
 127 }