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 "scrsnap.h"
  24 #include "draw.h"
  25
  26 #define CTRLKEY(x)      ((x) - 96)
  27 #define BADPOLLFLAGS    (POLLHUP | POLLERR | POLLNVAL)
  28 #define NTAGS           (sizeof(tags) - 1)
  29 #define NTERMS          (NTAGS * 2)
  30 #define TERMOPEN(i)     (terms[i].fd)
  31 #define TERMSNAP(i)     (strchr(TAGS_SAVED, tags[(i) % NTAGS]))
  32
  33 static char tags[] = TAGS;
  34 static struct term terms[NTERMS];
  35 static int tops[NTAGS]; /* top terms of tags */
  36 static int ctag;        /* current tag */
  37 static int ltag;        /* the last tag */
  38 static int exitit;
  39 static int hidden;
  40
  41 static int readchar(void)
  42 {
  43         char b;
  44         if (read(STDIN_FILENO, &b, 1) > 0)
  45                 return (int) b;
  46         return -1;
  47 }
  48
  49 static int cterm(void)
  50 {
  51         return tops[ctag] * NTAGS + ctag;
  52 }
  53
  54 static void term_switch(int oidx, int nidx, int show, int save, int load)
  55 {
  56         int flags = show ? (load ? TERM_REDRAW : TERM_VISIBLE) : TERM_HIDDEN;
  57         if (save && TERMOPEN(oidx) && TERMSNAP(oidx))
  58                 scr_snap(&terms[oidx]);
  59         term_save(&terms[oidx]);
  60         if (show && load && TERMOPEN(nidx) && TERMSNAP(nidx))
  61                 flags = scr_load(&terms[nidx]) ? TERM_REDRAW : TERM_VISIBLE;
  62         term_load(&terms[nidx], flags);
  63 }
  64
  65 static void showterm(int n)
  66 {
  67         if (cterm() == n)
  68                 return;
  69         if (ctag != n % NTAGS)
  70                 ltag = ctag;
  71         term_switch(cterm(), n, !hidden, !hidden, !hidden);
  72         ctag = n % NTAGS;
  73         tops[ctag] = n / NTAGS;
  74 }
  75
  76 static void showtag(int n)
  77 {
  78         showterm(tops[n] * NTAGS + n);
  79 }
  80
  81 static struct term *mainterm(void)
  82 {
  83         if (TERMOPEN(cterm()))
  84                 return &terms[cterm()];
  85         return NULL;
  86 }
  87
  88 static void exec_cmd(char *file)
  89 {
  90         if (!mainterm())
  91                 term_exec(file);
  92 }
  93
  94 static int altterm(int n)
  95 {
  96         return n < NTAGS ? n + NTAGS : n - NTAGS;
  97 }
  98
  99 static void nextterm(void)
 100 {
 101         int n = (cterm() + 1) % NTERMS;
 102         while (n != cterm()) {
 103                 if (TERMOPEN(n)) {
 104                         showterm(n);
 105                         break;
 106                 }
 107                 n = (n + 1) % NTERMS;
 108         }
 109 }
 110
 111 static void showtags(void)
 112 {
 113         int colors[] = {15, 4, 2};
 114         int c = 0;
 115         int r = pad_rows() - 1;
 116         int i;
 117         pad_put('T', r, c++, FGCOLOR, BGCOLOR);
 118         pad_put('A', r, c++, FGCOLOR, BGCOLOR);
 119         pad_put('G', r, c++, FGCOLOR, BGCOLOR);
 120         pad_put('S', r, c++, FGCOLOR, BGCOLOR);
 121         pad_put(':', r, c++, FGCOLOR, BGCOLOR);
 122         pad_put(' ', r, c++, FGCOLOR, BGCOLOR);
 123         for (i = 0; i < NTAGS; i++) {
 124                 int nt = 0;
 125                 if (TERMOPEN(i))
 126                         nt++;
 127                 if (TERMOPEN(altterm(i)))
 128                         nt++;
 129                 pad_put(i == ctag ? '(' : ' ', r, c++, FGCOLOR, BGCOLOR);
 130                 if (TERMSNAP(i))
 131                         pad_put(tags[i], r, c++, !nt ? BGCOLOR : colors[nt], 15);
 132                 else
 133                         pad_put(tags[i], r, c++, colors[nt], BGCOLOR);
 134                 pad_put(i == ctag ? ')' : ' ', r, c++, FGCOLOR, BGCOLOR);
 135         }
 136 }
 137
 138 static void directkey(void)
 139 {
 140         int c = readchar();
 141         if (c == ESC) {
 142                 switch ((c = readchar())) {
 143                 case 'c':
 144                         exec_cmd(SHELL);
 145                         return;
 146                 case 'm':
 147                         exec_cmd(MAIL);
 148                         return;
 149                 case 'e':
 150                         exec_cmd(EDITOR);
 151                         return;
 152                 case 'j':
 153                 case 'k':
 154                         showterm(altterm(cterm()));
 155                         return;
 156                 case 'o':
 157                         showtag(ltag);
 158                         return;
 159                 case 'p':
 160                         showtags();
 161                         return;
 162                 case '\t':
 163                         nextterm();
 164                         return;
 165                 case CTRLKEY('q'):
 166                         exitit = 1;
 167                         return;
 168                 case 's':
 169                         term_screenshot();
 170                         return;
 171                 case 'y':
 172                         term_switch(cterm(), cterm(), 1, 0, 1);
 173                         return;
 174                 default:
 175                         if (strchr(tags, c)) {
 176                                 showtag(strchr(tags, c) - tags);
 177                                 return;
 178                         }
 179                         if (mainterm())
 180                                 term_send(ESC);
 181                 }
 182         }
 183         if (c != -1 && mainterm())
 184                 term_send(c);
 185 }
 186
 187 static void temp_switch(int termid)
 188 {
 189         if (termid != cterm())
 190                 term_switch(cterm(), termid, 0, 0, 0);
 191 }
 192
 193 static void switch_back(int termid)
 194 {
 195         if (termid != cterm())
 196                 term_switch(termid, cterm(), 1, 0, 0);
 197 }
 198
 199 static int poll_all(void)
 200 {
 201         struct pollfd ufds[NTERMS + 1];
 202         int term_idx[NTERMS + 1];
 203         int i;
 204         int n = 1;
 205         ufds[0].fd = STDIN_FILENO;
 206         ufds[0].events = POLLIN;
 207         for (i = 0; i < NTERMS; i++) {
 208                 if (TERMOPEN(i)) {
 209                         ufds[n].fd = terms[i].fd;
 210                         ufds[n].events = POLLIN;
 211                         term_idx[n++] = i;
 212                 }
 213         }
 214         if (poll(ufds, n, 1000) < 1)
 215                 return 0;
 216         if (ufds[0].revents & BADPOLLFLAGS)
 217                 return 1;
 218         if (ufds[0].revents & POLLIN)
 219                 directkey();
 220         for (i = 1; i < n; i++) {
 221                 temp_switch(term_idx[i]);
 222                 if (ufds[i].revents & POLLIN)
 223                         term_read();
 224                 if (ufds[i].revents & BADPOLLFLAGS) {
 225                         scr_free(&terms[cterm()]);
 226                         term_end();
 227                 }
 228                 switch_back(term_idx[i]);
 229         }
 230         return 0;
 231 }
 232
 233 static void mainloop(void)
 234 {
 235         struct termios oldtermios, termios;
 236         tcgetattr(STDIN_FILENO, &termios);
 237         oldtermios = termios;
 238         cfmakeraw(&termios);
 239         tcsetattr(STDIN_FILENO, TCSAFLUSH, &termios);
 240         term_load(&terms[cterm()], TERM_REDRAW);
 241         while (!exitit)
 242                 if (poll_all())
 243                         break;
 244         tcsetattr(STDIN_FILENO, 0, &oldtermios);
 245 }
 246
 247 static void signalreceived(int n);
 248 static void signalregister(void)
 249 {
 250         signal(SIGUSR1, signalreceived);
 251         signal(SIGUSR2, signalreceived);
 252         signal(SIGCHLD, signalreceived);
 253 }
 254
 255 static void signalreceived(int n)
 256 {
 257         if (exitit)
 258                 return;
 259         /* racy, new signals may arrive before re-registeration */
 260         signalregister();
 261         switch (n) {
 262         case SIGUSR1:
 263                 hidden = 1;
 264                 term_switch(cterm(), cterm(), 0, 1, 0);
 265                 ioctl(STDIN_FILENO, VT_RELDISP, 1);
 266                 break;
 267         case SIGUSR2:
 268                 hidden = 0;
 269                 fb_cmap();
 270                 term_switch(cterm(), cterm(), 1, 0, 1);
 271                 break;
 272         case SIGCHLD:
 273                 while (waitpid(-1, NULL, WNOHANG) > 0)
 274                         ;
 275                 break;
 276         }
 277 }
 278
 279 static void setupsignals(void)
 280 {
 281         struct vt_mode vtm;
 282         vtm.mode = VT_PROCESS;
 283         vtm.waitv = 0;
 284         vtm.relsig = SIGUSR1;
 285         vtm.acqsig = SIGUSR2;
 286         vtm.frsig = 0;
 287         signalregister();
 288         ioctl(STDIN_FILENO, VT_SETMODE, &vtm);
 289 }
 290
 291 int main(void)
 292 {
 293         char *hide = "\x1b[?25l";
 294         char *clear = "\x1b[2J\x1b[H";
 295         char *show = "\x1b[?25h";
 296         write(STDOUT_FILENO, clear, strlen(clear));
 297         write(STDIN_FILENO, hide, strlen(hide));
 298         if (pad_init())
 299                 goto failed;
 300         setupsignals();
 301         fcntl(STDIN_FILENO, F_SETFL,
 302                 fcntl(STDIN_FILENO, F_GETFL) | O_NONBLOCK);
 303         mainloop();
 304         pad_free();
 305 failed:
 306         write(STDIN_FILENO, show, strlen(show));
 307         return 0;
 308 }