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 }
 134
 135 /* --------------------------------------------------------------------------------------------- */
 136
 137 static void
 138 handle_console_linux (console_action_t action)
 139 {
 140     char *tty_name;
 141     char *mc_conssaver;
 142     int status;
 143
 144     switch (action)
 145     {
 146     case CONSOLE_INIT:
 147         /* Close old pipe ends in case it is the 2nd time we run cons.saver */
 148         status = close (pipefd1[1]);
 149         status = close (pipefd2[0]);
 150         /* Create two pipes for communication */
 151         if (!((pipe (pipefd1) == 0) && ((pipe (pipefd2)) == 0)))
 152         {
 153             mc_global.tty.console_flag = '\0';
 154             break;
 155         }
 156         /* Get the console saver running */
 157         cons_saver_pid = fork ();
 158         if (cons_saver_pid < 0)
 159         {
 160             /* Cannot fork */
 161             /* Delete pipes */
 162             status = close (pipefd1[1]);
 163             status = close (pipefd1[0]);
 164             status = close (pipefd2[1]);
 165             status = close (pipefd2[0]);
 166             mc_global.tty.console_flag = '\0';
 167         }
 168         else if (cons_saver_pid > 0)
 169         {
 170             /* Parent */
 171             /* Close the extra pipe ends */
 172             status = close (pipefd1[0]);
 173             status = close (pipefd2[1]);
 174             /* Was the child successful? */
 175             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 176             if (mc_global.tty.console_flag == '\0')
 177             {
 178                 pid_t ret;
 179                 status = close (pipefd1[1]);
 180                 status = close (pipefd2[0]);
 181                 ret = waitpid (cons_saver_pid, &status, 0);
 182             }
 183         }
 184         else
 185         {
 186             /* Child */
 187             /* Close the extra pipe ends */
 188             status = close (pipefd1[1]);
 189             status = close (pipefd2[0]);
 190             tty_name = ttyname (0);
 191             /* Bind the pipe 0 to the standard input */
 192             do
 193             {
 194                 if (dup2 (pipefd1[0], 0) == -1)
 195                     break;
 196                 status = close (pipefd1[0]);
 197                 /* Bind the pipe 1 to the standard output */
 198                 if (dup2 (pipefd2[1], 1) == -1)
 199                     break;
 200
 201                 status = close (pipefd2[1]);
 202                 /* Bind standard error to /dev/null */
 203                 status = open ("/dev/null", O_WRONLY);
 204                 if (dup2 (status, 2) == -1)
 205                     break;
 206                 status = close (status);
 207                 if (tty_name)
 208                 {
 209                     /* Exec the console save/restore handler */
 210                     mc_conssaver = mc_build_filename (SAVERDIR, "cons.saver", NULL);
 211                     execl (mc_conssaver, "cons.saver", tty_name, (char *) NULL);
 212                 }
 213                 /* Console is not a tty or execl() failed */
 214             }
 215             while (0);
 216             mc_global.tty.console_flag = '\0';
 217             status = write (1, &mc_global.tty.console_flag, 1);
 218             _exit (3);
 219         }                       /* if (cons_saver_pid ...) */
 220         break;
 221
 222     case CONSOLE_DONE:
 223     case CONSOLE_SAVE:
 224     case CONSOLE_RESTORE:
 225         /* Is tty console? */
 226         if (mc_global.tty.console_flag == '\0')
 227             return;
 228         /* Paranoid: Is the cons.saver still running? */
 229         if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
 230         {
 231             cons_saver_pid = 0;
 232             mc_global.tty.console_flag = '\0';
 233             return;
 234         }
 235         /* Send command to the console handler */
 236         status = write (pipefd1[1], &action, 1);
 237         if (action != CONSOLE_DONE)
 238         {
 239             /* Wait the console handler to do its job */
 240             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 241         }
 242         if (action == CONSOLE_DONE || mc_global.tty.console_flag == '\0')
 243         {
 244             /* We are done -> Let's clean up */
 245             pid_t ret;
 246             close (pipefd1[1]);
 247             close (pipefd2[0]);
 248             ret = waitpid (cons_saver_pid, &status, 0);
 249             mc_global.tty.console_flag = '\0';
 250         }
 251         break;
 252     default:
 253         break;
 254     }
 255 }
 256
 257 #elif defined(__FreeBSD__)
 258
 259 /* --------------------------------------------------------------------------------------------- */
 260 /**
 261  * FreeBSD support copyright (C) 2003 Alexander Serkov <serkov@ukrpost.net>.
 262  * Support for screenmaps by Max Khon <fjoe@FreeBSD.org>
 263  */
 264
 265 static void
 266 console_init (void)
 267 {
 268     if (mc_global.tty.console_flag != '\0')
 269         return;
 270
 271     screen_info.size = sizeof (screen_info);
 272     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 273         return;
 274
 275     memset (&screen_shot, 0, sizeof (screen_shot));
 276     screen_shot.xsize = screen_info.mv_csz;
 277     screen_shot.ysize = screen_info.mv_rsz;
 278     screen_shot.buf = g_try_malloc (screen_info.mv_csz * screen_info.mv_rsz * 2);
 279     if (screen_shot.buf != NULL)
 280         mc_global.tty.console_flag = '\001';
 281 }
 282
 283 /* --------------------------------------------------------------------------------------------- */
 284
 285 static void
 286 set_attr (unsigned attr)
 287 {
 288     /*
 289      * Convert color indices returned by SCRSHOT (red=4, green=2, blue=1)
 290      * to indices for ANSI sequences (red=1, green=2, blue=4).
 291      */
 292     static const int color_map[8] = { 0, 4, 2, 6, 1, 5, 3, 7 };
 293     int bc, tc;
 294
 295     tc = attr & 0xF;
 296     bc = (attr >> 4) & 0xF;
 297
 298     printf ("\x1B[%d;%d;3%d;4%dm", (bc & 8) ? 5 : 25, (tc & 8) ? 1 : 22,
 299             color_map[tc & 7], color_map[bc & 7]);
 300 }
 301
 302 /* --------------------------------------------------------------------------------------------- */
 303
 304 static void
 305 console_restore (void)
 306 {
 307     int i, last;
 308
 309     if (mc_global.tty.console_flag == '\0')
 310         return;
 311
 312     cursor_to (0, 0);
 313
 314     /* restoring all content up to cursor position */
 315     last = screen_info.mv_row * screen_info.mv_csz + screen_info.mv_col;
 316     for (i = 0; i < last; ++i)
 317     {
 318         set_attr ((screen_shot.buf[i] >> 8) & 0xFF);
 319         putc (screen_shot.buf[i] & 0xFF, stdout);
 320     }
 321
 322     /* restoring cursor color */
 323     set_attr ((screen_shot.buf[last] >> 8) & 0xFF);
 324
 325     fflush (stdout);
 326 }
 327
 328 /* --------------------------------------------------------------------------------------------- */
 329
 330 static void
 331 console_shutdown (void)
 332 {
 333     if (mc_global.tty.console_flag == '\0')
 334         return;
 335
 336     g_free (screen_shot.buf);
 337
 338     mc_global.tty.console_flag = '\0';
 339 }
 340
 341 /* --------------------------------------------------------------------------------------------- */
 342
 343 static void
 344 console_save (void)
 345 {
 346     int i;
 347     scrmap_t map;
 348     scrmap_t revmap;
 349
 350     if (mc_global.tty.console_flag == '\0')
 351         return;
 352
 353     /* screen_info.size is already set in console_init() */
 354     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 355     {
 356         console_shutdown ();
 357         return;
 358     }
 359
 360     /* handle console resize */
 361     if (screen_info.mv_csz != screen_shot.xsize || screen_info.mv_rsz != screen_shot.ysize)
 362     {
 363         console_shutdown ();
 364         console_init ();
 365     }
 366
 367     if (ioctl (FD_OUT, CONS_SCRSHOT, &screen_shot) == -1)
 368     {
 369         console_shutdown ();
 370         return;
 371     }
 372
 373     if (ioctl (FD_OUT, GIO_SCRNMAP, &map) == -1)
 374     {
 375         console_shutdown ();
 376         return;
 377     }
 378
 379     for (i = 0; i < 256; i++)
 380     {
 381         char *p = memchr (map.scrmap, i, 256);
 382         revmap.scrmap[i] = p ? p - map.scrmap : i;
 383     }
 384
 385     for (i = 0; i < screen_shot.xsize * screen_shot.ysize; i++)
 386     {
 387         /* *INDENT-OFF* */
 388         screen_shot.buf[i] = (screen_shot.buf[i] & 0xff00)
 389             | (unsigned char) revmap.scrmap[screen_shot.buf[i] & 0xff];
 390         /* *INDENT-ON* */
 391     }
 392 }
 393
 394 /* --------------------------------------------------------------------------------------------- */
 395
 396 static void
 397 show_console_contents_freebsd (int starty, unsigned char begin_line, unsigned char end_line)
 398 {
 399     int col, line;
 400     char c;
 401
 402     if (mc_global.tty.console_flag == '\0')
 403         return;
 404
 405     for (line = begin_line; line <= end_line; line++)
 406     {
 407         tty_gotoyx (starty + line - begin_line, 0);
 408         for (col = 0; col < min (COLS, screen_info.mv_csz); col++)
 409         {
 410             c = screen_shot.buf[line * screen_info.mv_csz + col] & 0xFF;
 411             tty_print_char (c);
 412         }
 413     }
 414 }
 415
 416 /* --------------------------------------------------------------------------------------------- */
 417
 418 static void
 419 handle_console_freebsd (console_action_t action)
 420 {
 421     switch (action)
 422     {
 423     case CONSOLE_INIT:
 424         console_init ();
 425         break;
 426
 427     case CONSOLE_DONE:
 428         console_shutdown ();
 429         break;
 430
 431     case CONSOLE_SAVE:
 432         console_save ();
 433         break;
 434
 435     case CONSOLE_RESTORE:
 436         console_restore ();
 437         break;
 438     default:
 439         break;
 440     }
 441 }
 442 #endif /* __FreeBSD__ */
 443
 444 /* --------------------------------------------------------------------------------------------- */
 445 /*** public functions ****************************************************************************/
 446 /* --------------------------------------------------------------------------------------------- */
 447
 448 void
 449 show_console_contents (int starty, unsigned char begin_line, unsigned char end_line)
 450 {
 451     tty_set_normal_attrs ();
 452
 453     if (look_for_rxvt_extensions ())
 454     {
 455         show_rxvt_contents (starty, begin_line, end_line);
 456         return;
 457     }
 458 #ifdef __linux__
 459     show_console_contents_linux (starty, begin_line, end_line);
 460 #elif defined (__FreeBSD__)
 461     show_console_contents_freebsd (starty, begin_line, end_line);
 462 #else
 463     mc_global.tty.console_flag = '\0';
 464 #endif
 465 }
 466
 467 /* --------------------------------------------------------------------------------------------- */
 468
 469 void
 470 handle_console (console_action_t action)
 471 {
 472     (void) action;
 473
 474     if (look_for_rxvt_extensions ())
 475         return;
 476
 477 #ifdef __linux__
 478     handle_console_linux (action);
 479 #elif defined (__FreeBSD__)
 480     handle_console_freebsd (action);
 481 #endif
 482 }
 483
 484 /* --------------------------------------------------------------------------------------------- */