src/cons.handler.c

   1 /*
   2    Client interface for General purpose Linux console save/restore server
   3
   4    Copyright (C) 1994, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
   5    2006, 2007, 2011
   6    The Free Software Foundation, Inc.
   7
   8    This file is part of the Midnight Commander.
   9
  10    The Midnight Commander is free software: you can redistribute it
  11    and/or modify it under the terms of the GNU General Public License as
  12    published by the Free Software Foundation, either version 3 of the License,
  13    or (at your option) any later version.
  14
  15    The Midnight Commander is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 /** \file cons.handler.c
  25  *  \brief Source: client %interface for General purpose Linux console save/restore server
  26  */
  27
  28 #include <config.h>
  29
  30 #include <stdlib.h>
  31 #include <sys/wait.h>
  32 #include <signal.h>
  33 #include <stdio.h>
  34 #include <fcntl.h>
  35 #include <sys/types.h>
  36 #ifdef __FreeBSD__
  37 #include <sys/consio.h>
  38 #ifdef HAVE_SYS_IOCTL_H
  39 #include <sys/ioctl.h>
  40 #endif
  41 #endif
  42 #include <unistd.h>
  43
  44 #include "lib/global.h"
  45
  46 #include "lib/tty/tty.h"
  47 #include "lib/skin.h"           /* tty_set_normal_attrs */
  48 #include "lib/tty/win.h"
  49 #include "lib/util.h"           /* mc_build_filename() */
  50
  51 #include "consaver/cons.saver.h"
  52
  53 /*** global variables ****************************************************************************/
  54
  55 #ifdef __linux__
  56 int cons_saver_pid = 1;
  57 #endif /* __linux__ */
  58
  59 /*** file scope macro definitions ****************************************************************/
  60
  61 #if defined(__FreeBSD__)
  62 #define FD_OUT 1
  63 #define cursor_to(x, y) \
  64 do \
  65 { \
  66     printf("\x1B[%d;%df", (y) + 1, (x) + 1); \
  67     fflush(stdout); \
  68 } while (0)
  69 #endif /* __linux__ */
  70
  71 /*** file scope type declarations ****************************************************************/
  72
  73 /*** file scope variables ************************************************************************/
  74
  75 #ifdef __linux__
  76 /* The cons saver can't have a pid of 1, used to prevent bunches of
  77  * #ifdef linux */
  78 static int pipefd1[2] = { -1, -1 };
  79 static int pipefd2[2] = { -1, -1 };
  80 #elif defined(__FreeBSD__)
  81 static struct scrshot screen_shot;
  82 static struct vid_info screen_info;
  83 #endif /* __linux__ */
  84
  85 /*** file scope functions ************************************************************************/
  86 /* --------------------------------------------------------------------------------------------- */
  87
  88 #ifdef __linux__
  89 static void
  90 show_console_contents_linux (int starty, unsigned char begin_line, unsigned char end_line)
  91 {
  92     unsigned char message = 0;
  93     unsigned short bytes = 0;
  94     int i;
  95     ssize_t ret;
  96
  97     /* Is tty console? */
  98     if (mc_global.tty.console_flag == '\0')
  99         return;
 100     /* Paranoid: Is the cons.saver still running? */
 101     if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
 102     {
 103         cons_saver_pid = 0;
 104         mc_global.tty.console_flag = '\0';
 105         return;
 106     }
 107
 108     /* Send command to the console handler */
 109     message = CONSOLE_CONTENTS;
 110     ret = write (pipefd1[1], &message, 1);
 111     /* Check for outdated cons.saver */
 112     ret = read (pipefd2[0], &message, 1);
 113     if (message != CONSOLE_CONTENTS)
 114         return;
 115
 116     /* Send the range of lines that we want */
 117     ret = write (pipefd1[1], &begin_line, 1);
 118     ret = write (pipefd1[1], &end_line, 1);
 119     /* Read the corresponding number of bytes */
 120     ret = read (pipefd2[0], &bytes, 2);
 121
 122     /* Read the bytes and output them */
 123     for (i = 0; i < bytes; i++)
 124     {
 125         if ((i % COLS) == 0)
 126             tty_gotoyx (starty + (i / COLS), 0);
 127         ret = read (pipefd2[0], &message, 1);
 128         tty_print_char (message);
 129     }
 130
 131     /* Read the value of the mc_global.tty.console_flag */
 132     ret = read (pipefd2[0], &message, 1);
 133     (void) ret;
 134 }
 135
 136 /* --------------------------------------------------------------------------------------------- */
 137
 138 static void
 139 handle_console_linux (console_action_t action)
 140 {
 141     int status;
 142
 143     switch (action)
 144     {
 145     case CONSOLE_INIT:
 146         /* Close old pipe ends in case it is the 2nd time we run cons.saver */
 147         status = close (pipefd1[1]);
 148         status = close (pipefd2[0]);
 149         /* Create two pipes for communication */
 150         if (!((pipe (pipefd1) == 0) && ((pipe (pipefd2)) == 0)))
 151         {
 152             mc_global.tty.console_flag = '\0';
 153             break;
 154         }
 155         /* Get the console saver running */
 156         cons_saver_pid = fork ();
 157         if (cons_saver_pid < 0)
 158         {
 159             /* Cannot fork */
 160             /* Delete pipes */
 161             status = close (pipefd1[1]);
 162             status = close (pipefd1[0]);
 163             status = close (pipefd2[1]);
 164             status = close (pipefd2[0]);
 165             mc_global.tty.console_flag = '\0';
 166         }
 167         else if (cons_saver_pid > 0)
 168         {
 169             /* Parent */
 170             /* Close the extra pipe ends */
 171             status = close (pipefd1[0]);
 172             status = close (pipefd2[1]);
 173             /* Was the child successful? */
 174             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 175             if (mc_global.tty.console_flag == '\0')
 176             {
 177                 pid_t ret;
 178                 status = close (pipefd1[1]);
 179                 status = close (pipefd2[0]);
 180                 ret = waitpid (cons_saver_pid, &status, 0);
 181                 (void) ret;
 182             }
 183         }
 184         else
 185         {
 186             /* Child */
 187             char *tty_name;
 188
 189             /* Close the extra pipe ends */
 190             status = close (pipefd1[1]);
 191             status = close (pipefd2[0]);
 192             tty_name = ttyname (0);
 193             /* Bind the pipe 0 to the standard input */
 194             do
 195             {
 196                 if (dup2 (pipefd1[0], 0) == -1)
 197                     break;
 198                 status = close (pipefd1[0]);
 199                 /* Bind the pipe 1 to the standard output */
 200                 if (dup2 (pipefd2[1], 1) == -1)
 201                     break;
 202
 203                 status = close (pipefd2[1]);
 204                 /* Bind standard error to /dev/null */
 205                 status = open ("/dev/null", O_WRONLY);
 206                 if (dup2 (status, 2) == -1)
 207                     break;
 208                 status = close (status);
 209                 if (tty_name != NULL)
 210                 {
 211                     char *mc_conssaver;
 212
 213                     /* Exec the console save/restore handler */
 214                     mc_conssaver = mc_build_filename (SAVERDIR, "cons.saver", NULL);
 215                     execl (mc_conssaver, "cons.saver", tty_name, (char *) NULL);
 216                 }
 217                 /* Console is not a tty or execl() failed */
 218             }
 219             while (0);
 220             mc_global.tty.console_flag = '\0';
 221             status = write (1, &mc_global.tty.console_flag, 1);
 222             my_exit (3);
 223         }                       /* if (cons_saver_pid ...) */
 224         break;
 225
 226     case CONSOLE_DONE:
 227     case CONSOLE_SAVE:
 228     case CONSOLE_RESTORE:
 229         /* Is tty console? */
 230         if (mc_global.tty.console_flag == '\0')
 231             return;
 232         /* Paranoid: Is the cons.saver still running? */
 233         if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
 234         {
 235             cons_saver_pid = 0;
 236             mc_global.tty.console_flag = '\0';
 237             return;
 238         }
 239         /* Send command to the console handler */
 240         status = write (pipefd1[1], &action, 1);
 241         if (action != CONSOLE_DONE)
 242         {
 243             /* Wait the console handler to do its job */
 244             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 245         }
 246         if (action == CONSOLE_DONE || mc_global.tty.console_flag == '\0')
 247         {
 248             /* We are done -> Let's clean up */
 249             pid_t ret;
 250             close (pipefd1[1]);
 251             close (pipefd2[0]);
 252             ret = waitpid (cons_saver_pid, &status, 0);
 253             mc_global.tty.console_flag = '\0';
 254             (void) ret;
 255         }
 256         break;
 257     default:
 258         break;
 259     }
 260 }
 261
 262 #elif defined(__FreeBSD__)
 263
 264 /* --------------------------------------------------------------------------------------------- */
 265 /**
 266  * FreeBSD support copyright (C) 2003 Alexander Serkov <serkov@ukrpost.net>.
 267  * Support for screenmaps by Max Khon <fjoe@FreeBSD.org>
 268  */
 269
 270 static void
 271 console_init (void)
 272 {
 273     if (mc_global.tty.console_flag != '\0')
 274         return;
 275
 276     screen_info.size = sizeof (screen_info);
 277     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 278         return;
 279
 280     memset (&screen_shot, 0, sizeof (screen_shot));
 281     screen_shot.xsize = screen_info.mv_csz;
 282     screen_shot.ysize = screen_info.mv_rsz;
 283     screen_shot.buf = g_try_malloc (screen_info.mv_csz * screen_info.mv_rsz * 2);
 284     if (screen_shot.buf != NULL)
 285         mc_global.tty.console_flag = '\001';
 286 }
 287
 288 /* --------------------------------------------------------------------------------------------- */
 289
 290 static void
 291 set_attr (unsigned attr)
 292 {
 293     /*
 294      * Convert color indices returned by SCRSHOT (red=4, green=2, blue=1)
 295      * to indices for ANSI sequences (red=1, green=2, blue=4).
 296      */
 297     static const int color_map[8] = { 0, 4, 2, 6, 1, 5, 3, 7 };
 298     int bc, tc;
 299
 300     tc = attr & 0xF;
 301     bc = (attr >> 4) & 0xF;
 302
 303     printf ("\x1B[%d;%d;3%d;4%dm", (bc & 8) ? 5 : 25, (tc & 8) ? 1 : 22,
 304             color_map[tc & 7], color_map[bc & 7]);
 305 }
 306
 307 /* --------------------------------------------------------------------------------------------- */
 308
 309 static void
 310 console_restore (void)
 311 {
 312     int i, last;
 313
 314     if (mc_global.tty.console_flag == '\0')
 315         return;
 316
 317     cursor_to (0, 0);
 318
 319     /* restoring all content up to cursor position */
 320     last = screen_info.mv_row * screen_info.mv_csz + screen_info.mv_col;
 321     for (i = 0; i < last; ++i)
 322     {
 323         set_attr ((screen_shot.buf[i] >> 8) & 0xFF);
 324         putc (screen_shot.buf[i] & 0xFF, stdout);
 325     }
 326
 327     /* restoring cursor color */
 328     set_attr ((screen_shot.buf[last] >> 8) & 0xFF);
 329
 330     fflush (stdout);
 331 }
 332
 333 /* --------------------------------------------------------------------------------------------- */
 334
 335 static void
 336 console_shutdown (void)
 337 {
 338     if (mc_global.tty.console_flag == '\0')
 339         return;
 340
 341     g_free (screen_shot.buf);
 342
 343     mc_global.tty.console_flag = '\0';
 344 }
 345
 346 /* --------------------------------------------------------------------------------------------- */
 347
 348 static void
 349 console_save (void)
 350 {
 351     int i;
 352     scrmap_t map;
 353     scrmap_t revmap;
 354
 355     if (mc_global.tty.console_flag == '\0')
 356         return;
 357
 358     /* screen_info.size is already set in console_init() */
 359     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 360     {
 361         console_shutdown ();
 362         return;
 363     }
 364
 365     /* handle console resize */
 366     if (screen_info.mv_csz != screen_shot.xsize || screen_info.mv_rsz != screen_shot.ysize)
 367     {
 368         console_shutdown ();
 369         console_init ();
 370     }
 371
 372     if (ioctl (FD_OUT, CONS_SCRSHOT, &screen_shot) == -1)
 373     {
 374         console_shutdown ();
 375         return;
 376     }
 377
 378     if (ioctl (FD_OUT, GIO_SCRNMAP, &map) == -1)
 379     {
 380         console_shutdown ();
 381         return;
 382     }
 383
 384     for (i = 0; i < 256; i++)
 385     {
 386         char *p = memchr (map.scrmap, i, 256);
 387         revmap.scrmap[i] = p ? p - map.scrmap : i;
 388     }
 389
 390     for (i = 0; i < screen_shot.xsize * screen_shot.ysize; i++)
 391     {
 392         /* *INDENT-OFF* */
 393         screen_shot.buf[i] = (screen_shot.buf[i] & 0xff00)
 394             | (unsigned char) revmap.scrmap[screen_shot.buf[i] & 0xff];
 395         /* *INDENT-ON* */
 396     }
 397 }
 398
 399 /* --------------------------------------------------------------------------------------------- */
 400
 401 static void
 402 show_console_contents_freebsd (int starty, unsigned char begin_line, unsigned char end_line)
 403 {
 404     int col, line;
 405     char c;
 406
 407     if (mc_global.tty.console_flag == '\0')
 408         return;
 409
 410     for (line = begin_line; line <= end_line; line++)
 411     {
 412         tty_gotoyx (starty + line - begin_line, 0);
 413         for (col = 0; col < min (COLS, screen_info.mv_csz); col++)
 414         {
 415             c = screen_shot.buf[line * screen_info.mv_csz + col] & 0xFF;
 416             tty_print_char (c);
 417         }
 418     }
 419 }
 420
 421 /* --------------------------------------------------------------------------------------------- */
 422
 423 static void
 424 handle_console_freebsd (console_action_t action)
 425 {
 426     switch (action)
 427     {
 428     case CONSOLE_INIT:
 429         console_init ();
 430         break;
 431
 432     case CONSOLE_DONE:
 433         console_shutdown ();
 434         break;
 435
 436     case CONSOLE_SAVE:
 437         console_save ();
 438         break;
 439
 440     case CONSOLE_RESTORE:
 441         console_restore ();
 442         break;
 443     default:
 444         break;
 445     }
 446 }
 447 #endif /* __FreeBSD__ */
 448
 449 /* --------------------------------------------------------------------------------------------- */
 450 /*** public functions ****************************************************************************/
 451 /* --------------------------------------------------------------------------------------------- */
 452
 453 void
 454 show_console_contents (int starty, unsigned char begin_line, unsigned char end_line)
 455 {
 456     tty_set_normal_attrs ();
 457
 458     if (look_for_rxvt_extensions ())
 459     {
 460         show_rxvt_contents (starty, begin_line, end_line);
 461         return;
 462     }
 463 #ifdef __linux__
 464     show_console_contents_linux (starty, begin_line, end_line);
 465 #elif defined (__FreeBSD__)
 466     show_console_contents_freebsd (starty, begin_line, end_line);
 467 #else
 468     mc_global.tty.console_flag = '\0';
 469 #endif
 470 }
 471
 472 /* --------------------------------------------------------------------------------------------- */
 473
 474 void
 475 handle_console (console_action_t action)
 476 {
 477     (void) action;
 478
 479     if (look_for_rxvt_extensions ())
 480         return;
 481
 482 #ifdef __linux__
 483     handle_console_linux (action);
 484 #elif defined (__FreeBSD__)
 485     handle_console_freebsd (action);
 486 #endif
 487 }
 488
 489 /* --------------------------------------------------------------------------------------------- */