fbpad.c

   1 /*
   2  * fbpad - a small framebuffer virtual terminal
   3  *
   4  * Copyright (C) 2009-2013 Ali Gholami Rudi <ali at rudi dot ir>
   5  *
   6  * This program is released under the modified BSD license.
   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 "fbpad.h"
  21 #include "draw.h"
  22
  23 #define CTRLKEY(x)      ((x) - 96)
  24 #define BADPOLLFLAGS    (POLLHUP | POLLERR | POLLNVAL)
  25 #define NTAGS           (sizeof(tags) - 1)
  26 #define NTERMS          (NTAGS * 2)
  27 #define TERMOPEN(i)     (terms[i].fd)
  28 #define TERMSNAP(i)     (strchr(TAGS_SAVED, tags[(i) % NTAGS]))
  29
  30 static char tags[] = TAGS;
  31 static struct term terms[NTERMS];
  32 static int tops[NTAGS];         /* top terms of tags */
  33 static int ctag;                /* current tag */
  34 static int ltag;                /* the last tag */
  35 static int exitit;
  36 static int hidden;
  37 static int locked;
  38 static char pass[1024];
  39 static int passlen;
  40
  41 static int readchar(void)
  42 {
  43         char b;
  44         if (read(0, &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 **args)
  89 {
  90         if (!mainterm())
  91                 term_exec(args);
  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         char *shell[32] = SHELL;
 141         char *mail[32] = MAIL;
 142         char *editor[32] = EDITOR;
 143         int c = readchar();
 144         if (PASS && locked) {
 145                 if (c == '\r') {
 146                         pass[passlen] = '\0';
 147                         if (!strcmp(PASS, pass))
 148                                 locked = 0;
 149                         passlen = 0;
 150                         return;
 151                 }
 152                 if (isprint(c) && passlen + 1 < sizeof(pass))
 153                         pass[passlen++] = c;
 154                 return;
 155         }
 156         if (c == ESC) {
 157                 switch ((c = readchar())) {
 158                 case 'c':
 159                         exec_cmd(shell);
 160                         return;
 161                 case 'm':
 162                         exec_cmd(mail);
 163                         return;
 164                 case 'e':
 165                         exec_cmd(editor);
 166                         return;
 167                 case 'j':
 168                 case 'k':
 169                         showterm(altterm(cterm()));
 170                         return;
 171                 case 'o':
 172                         showtag(ltag);
 173                         return;
 174                 case 'p':
 175                         showtags();
 176                         return;
 177                 case '\t':
 178                         nextterm();
 179                         return;
 180                 case CTRLKEY('q'):
 181                         exitit = 1;
 182                         return;
 183                 case 's':
 184                         term_screenshot();
 185                         return;
 186                 case 'y':
 187                         term_switch(cterm(), cterm(), 1, 0, 1);
 188                         return;
 189                 case CTRLKEY('l'):
 190                         locked = 1;
 191                         passlen = 0;
 192                         return;
 193                 default:
 194                         if (strchr(tags, c)) {
 195                                 showtag(strchr(tags, c) - tags);
 196                                 return;
 197                         }
 198                         if (mainterm())
 199                                 term_send(ESC);
 200                 }
 201         }
 202         if (c != -1 && mainterm())
 203                 term_send(c);
 204 }
 205
 206 static void temp_switch(int termid)
 207 {
 208         if (termid != cterm())
 209                 term_switch(cterm(), termid, 0, 0, 0);
 210 }
 211
 212 static void switch_back(int termid)
 213 {
 214         if (termid != cterm())
 215                 term_switch(termid, cterm(), 1, 0, 0);
 216 }
 217
 218 static int poll_all(void)
 219 {
 220         struct pollfd ufds[NTERMS + 1];
 221         int term_idx[NTERMS + 1];
 222         int i;
 223         int n = 1;
 224         ufds[0].fd = 0;
 225         ufds[0].events = POLLIN;
 226         for (i = 0; i < NTERMS; i++) {
 227                 if (TERMOPEN(i)) {
 228                         ufds[n].fd = terms[i].fd;
 229                         ufds[n].events = POLLIN;
 230                         term_idx[n++] = i;
 231                 }
 232         }
 233         if (poll(ufds, n, 1000) < 1)
 234                 return 0;
 235         if (ufds[0].revents & BADPOLLFLAGS)
 236                 return 1;
 237         if (ufds[0].revents & POLLIN)
 238                 directkey();
 239         for (i = 1; i < n; i++) {
 240                 temp_switch(term_idx[i]);
 241                 if (ufds[i].revents & POLLIN)
 242                         term_read();
 243                 if (ufds[i].revents & BADPOLLFLAGS) {
 244                         scr_free(&terms[term_idx[i]]);
 245                         term_end();
 246                 }
 247                 switch_back(term_idx[i]);
 248         }
 249         return 0;
 250 }
 251
 252 static void mainloop(void)
 253 {
 254         struct termios oldtermios, termios;
 255         tcgetattr(0, &termios);
 256         oldtermios = termios;
 257         cfmakeraw(&termios);
 258         tcsetattr(0, TCSAFLUSH, &termios);
 259         term_load(&terms[cterm()], TERM_REDRAW);
 260         while (!exitit)
 261                 if (poll_all())
 262                         break;
 263         tcsetattr(0, 0, &oldtermios);
 264 }
 265
 266 static void signalreceived(int n);
 267 static void signalregister(void)
 268 {
 269         signal(SIGUSR1, signalreceived);
 270         signal(SIGUSR2, signalreceived);
 271         signal(SIGCHLD, signalreceived);
 272 }
 273
 274 static void signalreceived(int n)
 275 {
 276         if (exitit)
 277                 return;
 278         /* racy, new signals may arrive before re-registeration */
 279         signalregister();
 280         switch (n) {
 281         case SIGUSR1:
 282                 hidden = 1;
 283                 term_switch(cterm(), cterm(), 0, 1, 0);
 284                 ioctl(0, VT_RELDISP, 1);
 285                 break;
 286         case SIGUSR2:
 287                 hidden = 0;
 288                 fb_cmap();
 289                 term_switch(cterm(), cterm(), 1, 0, 1);
 290                 break;
 291         case SIGCHLD:
 292                 while (waitpid(-1, NULL, WNOHANG) > 0)
 293                         ;
 294                 break;
 295         }
 296 }
 297
 298 static void setupsignals(void)
 299 {
 300         struct vt_mode vtm;
 301         vtm.mode = VT_PROCESS;
 302         vtm.waitv = 0;
 303         vtm.relsig = SIGUSR1;
 304         vtm.acqsig = SIGUSR2;
 305         vtm.frsig = 0;
 306         signalregister();
 307         ioctl(0, VT_SETMODE, &vtm);
 308 }
 309
 310 int main(void)
 311 {
 312         char *hide = "\x1b[?25l";
 313         char *clear = "\x1b[2J\x1b[H";
 314         char *show = "\x1b[?25h";
 315         write(1, clear, strlen(clear));
 316         write(1, hide, strlen(hide));
 317         if (pad_init())
 318                 goto failed;
 319         setupsignals();
 320         fcntl(0, F_SETFL, fcntl(0, F_GETFL) | O_NONBLOCK);
 321         mainloop();
 322         pad_free();
 323 failed:
 324         write(1, show, strlen(show));
 325         return 0;
 326 }