fbpad.c

   1 /*
   2  * fbpad - a small framebuffer virtual terminal
   3  *
   4  * Copyright (C) 2009-2011 Ali Gholami Rudi <ali at rudi dot ir>
   5  *
   6  * This program is released under GNU GPL version 2.
   7  */
   8 #include <ctype.h>
   9 #include <errno.h>
  10 #include <fcntl.h>
  11 #include <poll.h>
  12 #include <signal.h>
  13 #include <string.h>
  14 #include <sys/ioctl.h>
  15 #include <sys/wait.h>
  16 #include <termios.h>
  17 #include <unistd.h>
  18 #include <linux/vt.h>
  19 #include "config.h"
  20 #include "pad.h"
  21 #include "term.h"
  22 #include "util.h"
  23 #include "draw.h"
  24
  25 #define CTRLKEY(x)      ((x) - 96)
  26 #define BADPOLLFLAGS    (POLLHUP | POLLERR | POLLNVAL)
  27 #define NTAGS           (sizeof(tags) - 1)
  28 #define NTERMS          (NTAGS * 2)
  29 #define TERMOPEN(i)     (terms[i].fd)
  30
  31 static char tags[] = TAGS;
  32 static struct term terms[NTERMS];
  33 static int tops[NTAGS]; /* top terms of tags */
  34 static int ctag;        /* current tag */
  35 static int ltag;        /* the last tag */
  36 static int exitit;
  37 static int hidden;
  38
  39 static int readchar(void)
  40 {
  41         char b;
  42         if (read(STDIN_FILENO, &b, 1) > 0)
  43                 return (int) b;
  44         return -1;
  45 }
  46
  47 static int cterm(void)
  48 {
  49         return tops[ctag] * NTAGS + ctag;
  50 }
  51
  52 static void term_switch(int oidx, int nidx, int show, int save, int load)
  53 {
  54         int flags = show ? (load ? TERM_REDRAW : TERM_VISIBLE) : TERM_HIDDEN;
  55         term_save(&terms[oidx]);
  56         term_load(&terms[nidx], flags);
  57 }
  58
  59 static void showterm(int n)
  60 {
  61         if (cterm() == n)
  62                 return;
  63         if (ctag != n % NTAGS)
  64                 ltag = ctag;
  65         term_switch(cterm(), n, !hidden, !hidden, !hidden);
  66         ctag = n % NTAGS;
  67         tops[ctag] = n / NTAGS;
  68 }
  69
  70 static void showtag(int n)
  71 {
  72         showterm(tops[n] * NTAGS + n);
  73 }
  74
  75 static struct term *mainterm(void)
  76 {
  77         if (TERMOPEN(cterm()))
  78                 return &terms[cterm()];
  79         return NULL;
  80 }
  81
  82 static void exec_cmd(char *file)
  83 {
  84         if (!mainterm())
  85                 term_exec(file);
  86 }
  87
  88 static int altterm(int n)
  89 {
  90         return n < NTAGS ? n + NTAGS : n - NTAGS;
  91 }
  92
  93 static void nextterm(void)
  94 {
  95         int n = (cterm() + 1) % NTERMS;
  96         while (n != cterm()) {
  97                 if (TERMOPEN(n)) {
  98                         showterm(n);
  99                         break;
 100                 }
 101                 n = (n + 1) % NTERMS;
 102         }
 103 }
 104
 105 static void showtags(void)
 106 {
 107         int colors[] = {15, 4, 2};
 108         int c = 0;
 109         int r = pad_rows() - 1;
 110         int i;
 111         pad_put('T', r, c++, FGCOLOR, BGCOLOR);
 112         pad_put('A', r, c++, FGCOLOR, BGCOLOR);
 113         pad_put('G', r, c++, FGCOLOR, BGCOLOR);
 114         pad_put('S', r, c++, FGCOLOR, BGCOLOR);
 115         pad_put(':', r, c++, FGCOLOR, BGCOLOR);
 116         pad_put(' ', r, c++, FGCOLOR, BGCOLOR);
 117         for (i = 0; i < NTAGS; i++) {
 118                 int nt = 0;
 119                 if (TERMOPEN(i))
 120                         nt++;
 121                 if (TERMOPEN(altterm(i)))
 122                         nt++;
 123                 pad_put(i == ctag ? '(' : ' ', r, c++, FGCOLOR, BGCOLOR);
 124                 pad_put(tags[i], r, c++, colors[nt], BGCOLOR);
 125                 pad_put(i == ctag ? ')' : ' ', r, c++, FGCOLOR, BGCOLOR);
 126         }
 127 }
 128
 129 static void directkey(void)
 130 {
 131         int c = readchar();
 132         if (c == ESC) {
 133                 switch ((c = readchar())) {
 134                 case 'c':
 135                         exec_cmd(SHELL);
 136                         return;
 137                 case 'm':
 138                         exec_cmd(MAIL);
 139                         return;
 140                 case 'e':
 141                         exec_cmd(EDITOR);
 142                         return;
 143                 case 'j':
 144                 case 'k':
 145                         showterm(altterm(cterm()));
 146                         return;
 147                 case 'o':
 148                         showtag(ltag);
 149                         return;
 150                 case 'p':
 151                         showtags();
 152                         return;
 153                 case '\t':
 154                         nextterm();
 155                         return;
 156                 case CTRLKEY('q'):
 157                         exitit = 1;
 158                         return;
 159                 case 's':
 160                         term_screenshot();
 161                         return;
 162                 default:
 163                         if (strchr(tags, c)) {
 164                                 showtag(strchr(tags, c) - tags);
 165                                 return;
 166                         }
 167                         if (mainterm())
 168                                 term_send(ESC);
 169                 }
 170         }
 171         if (c != -1 && mainterm())
 172                 term_send(c);
 173 }
 174
 175 static void temp_switch(int termid)
 176 {
 177         if (termid != cterm())
 178                 term_switch(cterm(), termid, 0, 0, 0);
 179 }
 180
 181 static void switch_back(int termid)
 182 {
 183         if (termid != cterm())
 184                 term_switch(termid, cterm(), 1, 0, 0);
 185 }
 186
 187 static int poll_all(void)
 188 {
 189         struct pollfd ufds[NTERMS + 1];
 190         int term_idx[NTERMS + 1];
 191         int i;
 192         int n = 1;
 193         ufds[0].fd = STDIN_FILENO;
 194         ufds[0].events = POLLIN;
 195         for (i = 0; i < NTERMS; i++) {
 196                 if (TERMOPEN(i)) {
 197                         ufds[n].fd = terms[i].fd;
 198                         ufds[n].events = POLLIN;
 199                         term_idx[n++] = i;
 200                 }
 201         }
 202         if (poll(ufds, n, 1000) < 1)
 203                 return 0;
 204         if (ufds[0].revents & BADPOLLFLAGS)
 205                 return 1;
 206         if (ufds[0].revents & POLLIN)
 207                 directkey();
 208         for (i = 1; i < n; i++) {
 209                 temp_switch(term_idx[i]);
 210                 if (ufds[i].revents & POLLIN)
 211                         term_read();
 212                 if (ufds[i].revents & BADPOLLFLAGS)
 213                         term_end();
 214                 switch_back(term_idx[i]);
 215         }
 216         return 0;
 217 }
 218
 219 static void mainloop(void)
 220 {
 221         struct termios oldtermios, termios;
 222         tcgetattr(STDIN_FILENO, &termios);
 223         oldtermios = termios;
 224         cfmakeraw(&termios);
 225         tcsetattr(STDIN_FILENO, TCSAFLUSH, &termios);
 226         term_load(&terms[cterm()], TERM_REDRAW);
 227         while (!exitit)
 228                 if (poll_all())
 229                         break;
 230         tcsetattr(STDIN_FILENO, 0, &oldtermios);
 231 }
 232
 233 static void signalreceived(int n);
 234 static void signalregister(void)
 235 {
 236         signal(SIGUSR1, signalreceived);
 237         signal(SIGUSR2, signalreceived);
 238         signal(SIGCHLD, signalreceived);
 239 }
 240
 241 static void signalreceived(int n)
 242 {
 243         if (exitit)
 244                 return;
 245         /* racy, new signals may arrive before re-registeration */
 246         signalregister();
 247         switch (n) {
 248         case SIGUSR1:
 249                 hidden = 1;
 250                 term_switch(cterm(), cterm(), 0, 1, 0);
 251                 ioctl(STDIN_FILENO, VT_RELDISP, 1);
 252                 break;
 253         case SIGUSR2:
 254                 hidden = 0;
 255                 fb_cmap();
 256                 term_switch(cterm(), cterm(), 1, 0, 1);
 257                 break;
 258         case SIGCHLD:
 259                 while (waitpid(-1, NULL, WNOHANG) > 0)
 260                         ;
 261                 break;
 262         }
 263 }
 264
 265 static void setupsignals(void)
 266 {
 267         struct vt_mode vtm;
 268         vtm.mode = VT_PROCESS;
 269         vtm.waitv = 0;
 270         vtm.relsig = SIGUSR1;
 271         vtm.acqsig = SIGUSR2;
 272         vtm.frsig = 0;
 273         signalregister();
 274         ioctl(STDIN_FILENO, VT_SETMODE, &vtm);
 275 }
 276
 277 int main(void)
 278 {
 279         char *hide = "\x1b[?25l";
 280         char *clear = "\x1b[2J\x1b[H";
 281         char *show = "\x1b[?25h";
 282         write(STDOUT_FILENO, clear, strlen(clear));
 283         write(STDIN_FILENO, hide, strlen(hide));
 284         if (pad_init())
 285                 goto failed;
 286         setupsignals();
 287         fcntl(STDIN_FILENO, F_SETFL,
 288                 fcntl(STDIN_FILENO, F_GETFL) | O_NONBLOCK);
 289         mainloop();
 290         pad_free();
 291 failed:
 292         write(STDIN_FILENO, show, strlen(show));
 293         return 0;
 294 }