git.mutantstargoat.com Git - visor/blob - visor/src/term.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <signal.h>
   5 #include <errno.h>
   6 #include <stdarg.h>
   7 #include <unistd.h>
   8 #include <fcntl.h>
   9 #include <termios.h>
  10 #include <sys/ioctl.h>
  11 #include "term.h"
  12
  13 static void sighandler(int s);
  14
  15 static int term_width, term_height;
  16 static int ttyfd = -1;
  17 static int selfpipe[2];
  18 static struct termios saved_term;
  19
  20 static void (*cb_resized)(int, int);
  21
  22
  23 int term_init(const char *ttypath)
  24 {
  25         struct termios term;
  26         struct winsize winsz;
  27
  28         if((ttyfd = open(ttypath ? ttypath : "/dev/tty", O_RDWR)) == -1) {
  29                 perror("failed to open /dev/tty");
  30                 return -1;
  31         }
  32         if(tcgetattr(ttyfd, &term) == -1) {
  33                 perror("failed to get terminal attr");
  34                 return -1;
  35         }
  36         saved_term = term;
  37         term.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
  38         term.c_oflag &= ~OPOST;
  39         term.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
  40         term.c_cflag = (term.c_cflag & ~(CSIZE | PARENB)) | CS8;
  41
  42         if(tcsetattr(ttyfd, TCSAFLUSH, &term) == -1) {
  43                 perror("failed to change terminal attributes");
  44                 return -1;
  45         }
  46
  47         ioctl(1, TIOCGWINSZ, &winsz);
  48         term_width = winsz.ws_col;
  49         term_height = winsz.ws_row;
  50
  51         pipe(selfpipe);
  52
  53         signal(SIGWINCH, sighandler);
  54         return 0;
  55 }
  56
  57 void term_cleanup(void)
  58 {
  59         tcsetattr(ttyfd, TCSAFLUSH, &saved_term);
  60         close(ttyfd);
  61         ttyfd = -1;
  62 }
  63
  64 void term_getsize(int *width, int *height)
  65 {
  66         *width = term_width;
  67         *height = term_height;
  68 }
  69
  70 void term_resize_func(void (*func)(int, int))
  71 {
  72         cb_resized = func;
  73 }
  74
  75
  76 static char termbuf[1024];
  77 static int termbuf_len;
  78
  79 void term_send(const char *s, int size)
  80 {
  81         if(size >= sizeof termbuf) {
  82                 /* too large, just flush the buffer and write directly to the tty */
  83                 term_flush();
  84                 write(ttyfd, s, size);
  85         } else {
  86                 if(size >= sizeof termbuf - termbuf_len) {
  87                         term_flush();
  88                 }
  89                 memcpy(termbuf + termbuf_len, s, size);
  90                 termbuf_len += size;
  91         }
  92 }
  93
  94 void term_puts(const char *s)
  95 {
  96         term_send(s, strlen(s));
  97 }
  98
  99 void term_printf(const char *fmt, ...)
 100 {
 101         static char *buf;
 102         static long bufsz;
 103         va_list ap;
 104         long len;
 105
 106         if(!buf) {
 107                 bufsz = 512;
 108                 if(!(buf = malloc(bufsz))) {
 109                         return;
 110                 }
 111         }
 112
 113         for(;;) {
 114                 va_start(ap, fmt);
 115                 len = vsnprintf(buf, bufsz, fmt, ap);
 116                 va_end(ap);
 117
 118                 if(len < bufsz) break;
 119                 if(len < 0) {
 120                         void *tmp;
 121                         long n = bufsz << 1;
 122                         if(!(tmp = realloc(buf, n))) {
 123                                 break;  /* if realloc fails, will result in truncated output */
 124                         }
 125                 }
 126         }
 127
 128         term_send(buf, len);
 129 }
 130
 131 void term_flush(void)
 132 {
 133         if(termbuf_len > 0) {
 134                 write(ttyfd, termbuf, termbuf_len);
 135                 termbuf_len = 0;
 136         }
 137 }
 138
 139 void term_clear(void)
 140 {
 141         term_puts("\033[2J");
 142 }
 143
 144 int term_getchar(void)
 145 {
 146         int res;
 147         char c;
 148         while((res = read(ttyfd, &c, 1)) < 0 && errno == EINTR);
 149         if(res <= 0) return -1;
 150         return c;
 151 }
 152
 153
 154 static void sighandler(int s)
 155 {
 156         struct winsize winsz;
 157
 158         signal(s, sighandler);
 159
 160         switch(s) {
 161         case SIGWINCH:
 162                 ioctl(1, TIOCGWINSZ, &winsz);
 163                 term_width = winsz.ws_col;
 164                 term_height = winsz.ws_row;
 165                 /* redraw */
 166                 break;
 167
 168         default:
 169                 break;
 170         }
 171 }