src/cons.handler.c

   1 /*
   2    Client interface for General purpose Linux console save/restore server
   3
   4    Copyright (C) 1994-2014
   5    Free Software Foundation, Inc.
   6
   7    This file is part of the Midnight Commander.
   8
   9    The Midnight Commander is free software: you can redistribute it
  10    and/or modify it under the terms of the GNU General Public License as
  11    published by the Free Software Foundation, either version 3 of the License,
  12    or (at your option) any later version.
  13
  14    The Midnight Commander is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23 /** \file cons.handler.c
  24  *  \brief Source: client %interface for General purpose Linux console save/restore server
  25  */
  26
  27 #include <config.h>
  28
  29 #include <stdlib.h>
  30 #include <sys/wait.h>
  31 #include <signal.h>
  32 #include <stdio.h>
  33 #include <fcntl.h>
  34 #include <sys/types.h>
  35 #ifdef __FreeBSD__
  36 #include <sys/consio.h>
  37 #ifdef HAVE_SYS_IOCTL_H
  38 #include <sys/ioctl.h>
  39 #endif
  40 #endif
  41
  42 #include "lib/global.h"
  43
  44 #include "lib/unixcompat.h"
  45 #include "lib/tty/tty.h"
  46 #include "lib/skin.h"           /* tty_set_normal_attrs */
  47 #include "lib/tty/win.h"
  48 #include "lib/util.h"           /* mc_build_filename() */
  49
  50 #include "consaver/cons.saver.h"
  51
  52 /*** global variables ****************************************************************************/
  53
  54 #ifdef __linux__
  55 int cons_saver_pid = 1;
  56 #endif /* __linux__ */
  57
  58 /*** file scope macro definitions ****************************************************************/
  59
  60 #if defined(__FreeBSD__)
  61 #define FD_OUT 1
  62 #define cursor_to(x, y) \
  63 do \
  64 { \
  65     printf("\x1B[%d;%df", (y) + 1, (x) + 1); \
  66     fflush(stdout); \
  67 } while (0)
  68 #endif /* __linux__ */
  69
  70 /*** file scope type declarations ****************************************************************/
  71
  72 /*** file scope variables ************************************************************************/
  73
  74 #ifdef __linux__
  75 /* The cons saver can't have a pid of 1, used to prevent bunches of
  76  * #ifdef linux */
  77 static int pipefd1[2] = { -1, -1 };
  78 static int pipefd2[2] = { -1, -1 };
  79 #elif defined(__FreeBSD__)
  80 static struct scrshot screen_shot;
  81 static struct vid_info screen_info;
  82 #endif /* __linux__ */
  83
  84 /*** file scope functions ************************************************************************/
  85 /* --------------------------------------------------------------------------------------------- */
  86
  87 #ifdef __linux__
  88 static void
  89 show_console_contents_linux (int starty, unsigned char begin_line, unsigned char end_line)
  90 {
  91     unsigned char message = 0;
  92     unsigned short bytes = 0;
  93     int i;
  94     ssize_t ret;
  95
  96     /* Is tty console? */
  97     if (mc_global.tty.console_flag == '\0')
  98         return;
  99     /* Paranoid: Is the cons.saver still running? */
 100     if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
 101     {
 102         cons_saver_pid = 0;
 103         mc_global.tty.console_flag = '\0';
 104         return;
 105     }
 106
 107     /* Send command to the console handler */
 108     message = CONSOLE_CONTENTS;
 109     ret = write (pipefd1[1], &message, 1);
 110     /* Check for outdated cons.saver */
 111     ret = read (pipefd2[0], &message, 1);
 112     if (message != CONSOLE_CONTENTS)
 113         return;
 114
 115     /* Send the range of lines that we want */
 116     ret = write (pipefd1[1], &begin_line, 1);
 117     ret = write (pipefd1[1], &end_line, 1);
 118     /* Read the corresponding number of bytes */
 119     ret = read (pipefd2[0], &bytes, 2);
 120
 121     /* Read the bytes and output them */
 122     for (i = 0; i < bytes; i++)
 123     {
 124         if ((i % COLS) == 0)
 125             tty_gotoyx (starty + (i / COLS), 0);
 126         ret = read (pipefd2[0], &message, 1);
 127         tty_print_char (message);
 128     }
 129
 130     /* Read the value of the mc_global.tty.console_flag */
 131     ret = read (pipefd2[0], &message, 1);
 132     (void) ret;
 133 }
 134
 135 /* --------------------------------------------------------------------------------------------- */
 136
 137 static void
 138 handle_console_linux (console_action_t action)
 139 {
 140     int status;
 141
 142     switch (action)
 143     {
 144     case CONSOLE_INIT:
 145         /* Close old pipe ends in case it is the 2nd time we run cons.saver */
 146         status = close (pipefd1[1]);
 147         status = close (pipefd2[0]);
 148         /* Create two pipes for communication */
 149         if (!((pipe (pipefd1) == 0) && ((pipe (pipefd2)) == 0)))
 150         {
 151             mc_global.tty.console_flag = '\0';
 152             break;
 153         }
 154         /* Get the console saver running */
 155         cons_saver_pid = fork ();
 156         if (cons_saver_pid < 0)
 157         {
 158             /* Cannot fork */
 159             /* Delete pipes */
 160             status = close (pipefd1[1]);
 161             status = close (pipefd1[0]);
 162             status = close (pipefd2[1]);
 163             status = close (pipefd2[0]);
 164             mc_global.tty.console_flag = '\0';
 165         }
 166         else if (cons_saver_pid > 0)
 167         {
 168             /* Parent */
 169             /* Close the extra pipe ends */
 170             status = close (pipefd1[0]);
 171             status = close (pipefd2[1]);
 172             /* Was the child successful? */
 173             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 174             if (mc_global.tty.console_flag == '\0')
 175             {
 176                 pid_t ret;
 177                 status = close (pipefd1[1]);
 178                 status = close (pipefd2[0]);
 179                 ret = waitpid (cons_saver_pid, &status, 0);
 180                 (void) ret;
 181             }
 182         }
 183         else
 184         {
 185             /* Child */
 186             char *tty_name;
 187
 188             /* Close the extra pipe ends */
 189             status = close (pipefd1[1]);
 190             status = close (pipefd2[0]);
 191             tty_name = ttyname (0);
 192             /* Bind the pipe 0 to the standard input */
 193             do
 194             {
 195                 if (dup2 (pipefd1[0], STDIN_FILENO) == -1)
 196                     break;
 197                 status = close (pipefd1[0]);
 198                 /* Bind the pipe 1 to the standard output */
 199                 if (dup2 (pipefd2[1], STDOUT_FILENO) == -1)
 200                     break;
 201
 202                 status = close (pipefd2[1]);
 203                 /* Bind standard error to /dev/null */
 204                 status = open ("/dev/null", O_WRONLY);
 205                 if (dup2 (status, STDERR_FILENO) == -1)
 206                     break;
 207                 status = close (status);
 208                 if (tty_name != NULL)
 209                 {
 210                     char *mc_conssaver;
 211
 212                     /* Exec the console save/restore handler */
 213                     mc_conssaver = mc_build_filename (SAVERDIR, "cons.saver", NULL);
 214                     execl (mc_conssaver, "cons.saver", tty_name, (char *) NULL);
 215                 }
 216                 /* Console is not a tty or execl() failed */
 217             }
 218             while (0);
 219             mc_global.tty.console_flag = '\0';
 220             status = write (1, &mc_global.tty.console_flag, 1);
 221             my_exit (3);
 222         }                       /* if (cons_saver_pid ...) */
 223         break;
 224
 225     case CONSOLE_DONE:
 226     case CONSOLE_SAVE:
 227     case CONSOLE_RESTORE:
 228         /* Is tty console? */
 229         if (mc_global.tty.console_flag == '\0')
 230             return;
 231         /* Paranoid: Is the cons.saver still running? */
 232         if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
 233         {
 234             cons_saver_pid = 0;
 235             mc_global.tty.console_flag = '\0';
 236             return;
 237         }
 238         /* Send command to the console handler */
 239         status = write (pipefd1[1], &action, 1);
 240         if (action != CONSOLE_DONE)
 241         {
 242             /* Wait the console handler to do its job */
 243             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 244         }
 245         if (action == CONSOLE_DONE || mc_global.tty.console_flag == '\0')
 246         {
 247             /* We are done -> Let's clean up */
 248             pid_t ret;
 249             close (pipefd1[1]);
 250             close (pipefd2[0]);
 251             ret = waitpid (cons_saver_pid, &status, 0);
 252             (void) ret;
 253             mc_global.tty.console_flag = '\0';
 254         }
 255         break;
 256     default:
 257         break;
 258     }
 259 }
 260
 261 #elif defined(__FreeBSD__)
 262
 263 /* --------------------------------------------------------------------------------------------- */
 264 /**
 265  * FreeBSD support copyright (C) 2003 Alexander Serkov <serkov@ukrpost.net>.
 266  * Support for screenmaps by Max Khon <fjoe@FreeBSD.org>
 267  */
 268
 269 static void
 270 console_init (void)
 271 {
 272     if (mc_global.tty.console_flag != '\0')
 273         return;
 274
 275     screen_info.size = sizeof (screen_info);
 276     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 277         return;
 278
 279     memset (&screen_shot, 0, sizeof (screen_shot));
 280     screen_shot.xsize = screen_info.mv_csz;
 281     screen_shot.ysize = screen_info.mv_rsz;
 282     screen_shot.buf = g_try_malloc (screen_info.mv_csz * screen_info.mv_rsz * 2);
 283     if (screen_shot.buf != NULL)
 284         mc_global.tty.console_flag = '\001';
 285 }
 286
 287 /* --------------------------------------------------------------------------------------------- */
 288
 289 static void
 290 set_attr (unsigned attr)
 291 {
 292     /*
 293      * Convert color indices returned by SCRSHOT (red=4, green=2, blue=1)
 294      * to indices for ANSI sequences (red=1, green=2, blue=4).
 295      */
 296     static const int color_map[8] = { 0, 4, 2, 6, 1, 5, 3, 7 };
 297     int bc, tc;
 298
 299     tc = attr & 0xF;
 300     bc = (attr >> 4) & 0xF;
 301
 302     printf ("\x1B[%d;%d;3%d;4%dm", (bc & 8) ? 5 : 25, (tc & 8) ? 1 : 22,
 303             color_map[tc & 7], color_map[bc & 7]);
 304 }
 305
 306 /* --------------------------------------------------------------------------------------------- */
 307
 308 static void
 309 console_restore (void)
 310 {
 311     int i, last;
 312
 313     if (mc_global.tty.console_flag == '\0')
 314         return;
 315
 316     cursor_to (0, 0);
 317
 318     /* restoring all content up to cursor position */
 319     last = screen_info.mv_row * screen_info.mv_csz + screen_info.mv_col;
 320     for (i = 0; i < last; ++i)
 321     {
 322         set_attr ((screen_shot.buf[i] >> 8) & 0xFF);
 323         putc (screen_shot.buf[i] & 0xFF, stdout);
 324     }
 325
 326     /* restoring cursor color */
 327     set_attr ((screen_shot.buf[last] >> 8) & 0xFF);
 328
 329     fflush (stdout);
 330 }
 331
 332 /* --------------------------------------------------------------------------------------------- */
 333
 334 static void
 335 console_shutdown (void)
 336 {
 337     if (mc_global.tty.console_flag == '\0')
 338         return;
 339
 340     g_free (screen_shot.buf);
 341
 342     mc_global.tty.console_flag = '\0';
 343 }
 344
 345 /* --------------------------------------------------------------------------------------------- */
 346
 347 static void
 348 console_save (void)
 349 {
 350     int i;
 351     scrmap_t map;
 352     scrmap_t revmap;
 353
 354     if (mc_global.tty.console_flag == '\0')
 355         return;
 356
 357     /* screen_info.size is already set in console_init() */
 358     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 359     {
 360         console_shutdown ();
 361         return;
 362     }
 363
 364     /* handle console resize */
 365     if (screen_info.mv_csz != screen_shot.xsize || screen_info.mv_rsz != screen_shot.ysize)
 366     {
 367         console_shutdown ();
 368         console_init ();
 369     }
 370
 371     if (ioctl (FD_OUT, CONS_SCRSHOT, &screen_shot) == -1)
 372     {
 373         console_shutdown ();
 374         return;
 375     }
 376
 377     if (ioctl (FD_OUT, GIO_SCRNMAP, &map) == -1)
 378     {
 379         console_shutdown ();
 380         return;
 381     }
 382
 383     for (i = 0; i < 256; i++)
 384     {
 385         char *p = memchr (map.scrmap, i, 256);
 386         revmap.scrmap[i] = p ? p - map.scrmap : i;
 387     }
 388
 389     for (i = 0; i < screen_shot.xsize * screen_shot.ysize; i++)
 390     {
 391         /* *INDENT-OFF* */
 392         screen_shot.buf[i] = (screen_shot.buf[i] & 0xff00)
 393             | (unsigned char) revmap.scrmap[screen_shot.buf[i] & 0xff];
 394         /* *INDENT-ON* */
 395     }
 396 }
 397
 398 /* --------------------------------------------------------------------------------------------- */
 399
 400 static void
 401 show_console_contents_freebsd (int starty, unsigned char begin_line, unsigned char end_line)
 402 {
 403     int col, line;
 404     char c;
 405
 406     if (mc_global.tty.console_flag == '\0')
 407         return;
 408
 409     for (line = begin_line; line <= end_line; line++)
 410     {
 411         tty_gotoyx (starty + line - begin_line, 0);
 412         for (col = 0; col < min (COLS, screen_info.mv_csz); col++)
 413         {
 414             c = screen_shot.buf[line * screen_info.mv_csz + col] & 0xFF;
 415             tty_print_char (c);
 416         }
 417     }
 418 }
 419
 420 /* --------------------------------------------------------------------------------------------- */
 421
 422 static void
 423 handle_console_freebsd (console_action_t action)
 424 {
 425     switch (action)
 426     {
 427     case CONSOLE_INIT:
 428         console_init ();
 429         break;
 430
 431     case CONSOLE_DONE:
 432         console_shutdown ();
 433         break;
 434
 435     case CONSOLE_SAVE:
 436         console_save ();
 437         break;
 438
 439     case CONSOLE_RESTORE:
 440         console_restore ();
 441         break;
 442     default:
 443         break;
 444     }
 445 }
 446 #endif /* __FreeBSD__ */
 447
 448 /* --------------------------------------------------------------------------------------------- */
 449 /*** public functions ****************************************************************************/
 450 /* --------------------------------------------------------------------------------------------- */
 451
 452 void
 453 show_console_contents (int starty, unsigned char begin_line, unsigned char end_line)
 454 {
 455     tty_set_normal_attrs ();
 456
 457     if (look_for_rxvt_extensions ())
 458     {
 459         show_rxvt_contents (starty, begin_line, end_line);
 460         return;
 461     }
 462 #ifdef __linux__
 463     show_console_contents_linux (starty, begin_line, end_line);
 464 #elif defined (__FreeBSD__)
 465     show_console_contents_freebsd (starty, begin_line, end_line);
 466 #else
 467     mc_global.tty.console_flag = '\0';
 468 #endif
 469 }
 470
 471 /* --------------------------------------------------------------------------------------------- */
 472
 473 void
 474 handle_console (console_action_t action)
 475 {
 476     (void) action;
 477
 478     if (look_for_rxvt_extensions ())
 479         return;
 480
 481 #ifdef __linux__
 482     handle_console_linux (action);
 483 #elif defined (__FreeBSD__)
 484     handle_console_freebsd (action);
 485 #endif
 486 }
 487
 488 /* --------------------------------------------------------------------------------------------- */