fbpterm.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include <sys/types.h>
   4 #include <poll.h>
   5 #include <unistd.h>
   6 #include <ctype.h>
   7 #include <pty.h>
   8 #include "pad.h"
   9 #include "util.h"
  10
  11 #define SHELL           "/bin/bash"
  12 #define ESC             27
  13 #define MAXESCARGS      32
  14 #define FGCOLOR         0
  15 #define BGCOLOR         7
  16
  17 static pid_t pid;
  18 static int fd;
  19
  20 static void execshell(void)
  21 {
  22         if ((pid = forkpty(&fd, NULL, NULL, NULL)) == -1)
  23                 xerror("failed to create a pty");
  24         if (!pid) {
  25                 setenv("TERM", "linux", 1);
  26                 execl(SHELL, SHELL, NULL);
  27                 exit(1);
  28         }
  29 }
  30
  31 static void setsize(void)
  32 {
  33         struct winsize size;
  34         size.ws_col = pad_cols();
  35         size.ws_row = pad_rows();
  36         size.ws_xpixel = 0;
  37         size.ws_ypixel = 0;
  38         ioctl(fd, TIOCSWINSZ, &size);
  39 }
  40
  41 static int readpty(void)
  42 {
  43         char b;
  44         if (read(fd, &b, 1) > 0)
  45                 return (int) b;
  46         return -1;
  47 }
  48
  49 static int readchar(void)
  50 {
  51         char b;
  52         if (read(STDIN_FILENO, &b, 1) > 0)
  53                 return (int) b;
  54         return -1;
  55 }
  56
  57 static void writechar(int c)
  58 {
  59         unsigned char b = (unsigned char) c;
  60         write(fd, &b, 1);
  61 }
  62
  63 static void writepty(int c)
  64 {
  65         pad_add(c);
  66 }
  67
  68 static void setmode(int m)
  69 {
  70         if (m == 0) {
  71                 pad_fg(FGCOLOR);
  72                 pad_bg(BGCOLOR);
  73         }
  74         if (m >= 30 && m <= 37)
  75                 pad_fg(m - 30);
  76         if (m >= 40 && m <= 47)
  77                 pad_bg(m - 40);
  78 }
  79
  80 static void kill_line(void)
  81 {
  82         int i;
  83         for (i = pad_col(); i < pad_cols(); i++)
  84                 pad_put('\0', pad_row(), i);
  85         pad_move(pad_row(), pad_col());
  86 }
  87
  88 static void escape_bracket(void)
  89 {
  90         int args[MAXESCARGS] = {0};
  91         int i;
  92         int n = -1;
  93         int c = 0;
  94         for (i = 0; i < ARRAY_SIZE(args) && !isalpha(c); i++) {
  95                 int arg = 0;
  96                 while (isdigit((c = readpty())))
  97                         arg = arg * 10 + (c - '0');
  98                 args[++n] = arg;
  99         }
 100         switch (c) {
 101         case 'H':
 102         case 'f':
 103                 pad_move(MAX(0, args[0] - 1), MAX(0, args[1] - 1));
 104                 break;
 105         case 'J':
 106                 pad_blank();
 107                 pad_move(0, 0);
 108                 break;
 109         case 'A':
 110                 pad_move(pad_row() - MAX(1, args[0]), pad_col());
 111                 break;
 112         case 'B':
 113                 pad_move(pad_row() + MAX(1, args[0]), pad_col());
 114                 break;
 115         case 'C':
 116                 pad_move(pad_row(), pad_col() + MAX(1, args[0]));
 117                 break;
 118         case 'D':
 119                 pad_move(pad_row(), pad_col() - MAX(1, args[0]));
 120                 break;
 121         case 'K':
 122                 kill_line();
 123                 break;
 124         case 'm':
 125                 for (i = 0; i < n; i++)
 126                         setmode(args[i]);
 127                 if (!n)
 128                         setmode(0);
 129                 break;
 130         default:
 131                 printf("unknown escape bracket char <%c>\n", c);
 132         }
 133 }
 134
 135 static void escape(void)
 136 {
 137         int c = readpty();
 138         if (c == '[') {
 139                 escape_bracket();
 140         } else {
 141                 printf("unknown escape char <%c>\n", c);
 142                 writepty(ESC);
 143                 writepty(c);
 144                 return;
 145         }
 146 }
 147
 148 static void shcmds(void)
 149 {
 150         int c = readpty();
 151         if (c == ESC)
 152                 escape();
 153         else
 154                 writepty(c);
 155 }
 156
 157 static void directkey(void)
 158 {
 159         int c = readchar();
 160         writechar(c);
 161 }
 162
 163 static void mainloop(void)
 164 {
 165         struct pollfd ufds[2];
 166         int rv;
 167         struct termios oldtermios, termios;
 168         tcgetattr(STDIN_FILENO, &termios);
 169         oldtermios = termios;
 170         cfmakeraw(&termios);
 171         tcsetattr(STDIN_FILENO, TCSAFLUSH, &termios);
 172         ufds[0].fd = STDIN_FILENO;
 173         ufds[0].events = POLLIN;
 174         ufds[1].fd = fd;
 175         ufds[1].events = POLLIN;
 176         while ((rv = poll(ufds, 2, 1000)) != -1) {
 177                 if ((ufds[0].revents | ufds[1].revents) &
 178                         (POLLHUP | POLLERR | POLLNVAL))
 179                         break;
 180                 if (ufds[0].revents & POLLIN)
 181                         directkey();
 182                 if (ufds[1].revents & POLLIN)
 183                         shcmds();
 184         }
 185         tcsetattr(STDIN_FILENO, 0, &oldtermios);
 186 }
 187
 188 int main(void)
 189 {
 190         execshell();
 191         pad_init();
 192         setsize();
 193         setmode(0);
 194         pad_blank();
 195         mainloop();
 196         pad_free();
 197         return 0;
 198 }