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 108     /* Check for outdated cons.saver */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