1 files changed, 502 insertions, 0 deletions
diff --git a/src/cons.handler.c b/src/cons.handler.c
new file mode 100644
index 0000000..d747ff3
--- /dev/null
+++ b/src/cons.handler.c
@@ -0,0 +1,502 @@
+/*
+   Client interface for General purpose Linux console save/restore server
+
+   Copyright (C) 1994-2023
+   Free Software Foundation, Inc.
+
+   This file is part of the Midnight Commander.
+
+   The Midnight Commander is free software: you can redistribute it
+   and/or modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the License,
+   or (at your option) any later version.
+
+   The Midnight Commander is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** \file cons.handler.c
+ *  \brief Source: client %interface for General purpose Linux console save/restore server
+ */
+
+#include <config.h>
+
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include <stdio.h>
+#include <sys/types.h>
+#ifdef __FreeBSD__
+#include <sys/consio.h>
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#endif
+
+#include "lib/global.h"
+
+#include "lib/unixcompat.h"
+#include "lib/tty/tty.h"
+#include "lib/tty/color.h"      /* tty_set_normal_attrs */
+#include "lib/tty/win.h"
+#include "lib/util.h"           /* mc_build_filename() */
+
+#include "consaver/cons.saver.h"
+
+/*** global variables ****************************************************************************/
+
+#ifdef __linux__
+int cons_saver_pid = 1;
+#endif /* __linux__ */
+
+/*** file scope macro definitions ****************************************************************/
+
+#if defined(__FreeBSD__)
+#define FD_OUT 1
+#define cursor_to(x, y) \
+do \
+{ \
+    printf("\x1B[%d;%df", (y) + 1, (x) + 1); \
+    fflush(stdout); \
+} while (0)
+#endif /* __linux__ */
+
+/*** file scope type declarations ****************************************************************/
+
+/*** forward declarations (file scope functions) *************************************************/
+
+/*** file scope variables ************************************************************************/
+
+#ifdef __linux__
+/* The cons saver can't have a pid of 1, used to prevent bunches of
+ * #ifdef linux */
+static int pipefd1[2] = { -1, -1 };
+static int pipefd2[2] = { -1, -1 };
+#elif defined(__FreeBSD__)
+static struct scrshot screen_shot;
+static struct vid_info screen_info;
+#endif /* __linux__ */
+
+/* --------------------------------------------------------------------------------------------- */
+/*** file scope functions ************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+#ifdef __linux__
+static void
+show_console_contents_linux (int starty, unsigned char begin_line, unsigned char end_line)
+{
+    unsigned char message = 0;
+    unsigned short bytes = 0;
+    int i;
+    ssize_t ret;
+
+    /* Is tty console? */
+    if (mc_global.tty.console_flag == '\0')
+        return;
+    /* Paranoid: Is the cons.saver still running? */
+    if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
+    {
+        cons_saver_pid = 0;
+        mc_global.tty.console_flag = '\0';
+        return;
+    }
+
+    /* Send command to the console handler */
+    message = CONSOLE_CONTENTS;
+    ret = write (pipefd1[1], &message, 1);
+    /* Check for outdated cons.saver */
+    ret = read (pipefd2[0], &message, 1);
+    if (message != CONSOLE_CONTENTS)
+        return;
+
+    /* Send the range of lines that we want */
+    ret = write (pipefd1[1], &begin_line, 1);
+    ret = write (pipefd1[1], &end_line, 1);
+    /* Read the corresponding number of bytes */
+    ret = read (pipefd2[0], &bytes, 2);
+
+    /* Read the bytes and output them */
+    for (i = 0; i < bytes; i++)
+    {
+        if ((i % COLS) == 0)
+            tty_gotoyx (starty + (i / COLS), 0);
+        ret = read (pipefd2[0], &message, 1);
+        tty_print_char (message);
+    }
+
+    /* Read the value of the mc_global.tty.console_flag */
+    ret = read (pipefd2[0], &message, 1);
+    (void) ret;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+handle_console_linux (console_action_t action)
+{
+    int status;
+
+    switch (action)
+    {
+    case CONSOLE_INIT:
+        /* Close old pipe ends in case it is the 2nd time we run cons.saver */
+        status = close (pipefd1[1]);
+        status = close (pipefd2[0]);
+        /* Create two pipes for communication */
+        if (!((pipe (pipefd1) == 0) && ((pipe (pipefd2)) == 0)))
+        {
+            mc_global.tty.console_flag = '\0';
+            break;
+        }
+        /* Get the console saver running */
+        cons_saver_pid = fork ();
+        if (cons_saver_pid < 0)
+        {
+            /* Cannot fork */
+            /* Delete pipes */
+            status = close (pipefd1[1]);
+            status = close (pipefd1[0]);
+            status = close (pipefd2[1]);
+            status = close (pipefd2[0]);
+            mc_global.tty.console_flag = '\0';
+        }
+        else if (cons_saver_pid > 0)
+        {
+            /* Parent */
+            /* Close the extra pipe ends */
+            status = close (pipefd1[0]);
+            status = close (pipefd2[1]);
+            /* Was the child successful? */
+            status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
+            if (mc_global.tty.console_flag == '\0')
+            {
+                pid_t ret;
+                status = close (pipefd1[1]);
+                status = close (pipefd2[0]);
+                ret = waitpid (cons_saver_pid, &status, 0);
+                (void) ret;
+            }
+        }
+        else
+        {
+            /* Child */
+            char *tty_name;
+
+            /* Close the extra pipe ends */
+            status = close (pipefd1[1]);
+            status = close (pipefd2[0]);
+            tty_name = ttyname (0);
+            /* Bind the pipe 0 to the standard input */
+            do
+            {
+                gboolean ok;
+
+                if (dup2 (pipefd1[0], STDIN_FILENO) == -1)
+                    break;
+                status = close (pipefd1[0]);
+                /* Bind the pipe 1 to the standard output */
+                if (dup2 (pipefd2[1], STDOUT_FILENO) == -1)
+                    break;
+
+                status = close (pipefd2[1]);
+                /* Bind standard error to /dev/null */
+                status = open ("/dev/null", O_WRONLY);
+                if (status == -1)
+                    break;
+                ok = dup2 (status, STDERR_FILENO) != -1;
+                status = close (status);
+                if (!ok)
+                    break;
+
+                if (tty_name != NULL)
+                {
+                    char *mc_conssaver;
+
+                    /* Exec the console save/restore handler */
+                    mc_conssaver = mc_build_filename (SAVERDIR, "cons.saver", (char *) NULL);
+                    execl (mc_conssaver, "cons.saver", tty_name, (char *) NULL);
+                }
+                /* Console is not a tty or execl() failed */
+            }
+            while (0);
+            mc_global.tty.console_flag = '\0';
+            status = write (1, &mc_global.tty.console_flag, 1);
+            my_exit (3);
+        }                       /* if (cons_saver_pid ...) */
+        break;
+
+    case CONSOLE_DONE:
+    case CONSOLE_SAVE:
+    case CONSOLE_RESTORE:
+        /* Is tty console? */
+        if (mc_global.tty.console_flag == '\0')
+            return;
+        /* Paranoid: Is the cons.saver still running? */
+        if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
+        {
+            cons_saver_pid = 0;
+            mc_global.tty.console_flag = '\0';
+            return;
+        }
+        /* Send command to the console handler */
+        {
+            /* Convert enum (i.e. int) to char to write the correct value
+             * (the least byte) regardless of machine endianness. */
+            char act = (char) action;
+
+            status = write (pipefd1[1], &act, 1);
+        }
+        if (action != CONSOLE_DONE)
+        {
+            /* Wait the console handler to do its job */
+            status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
+        }
+        if (action == CONSOLE_DONE || mc_global.tty.console_flag == '\0')
+        {
+            /* We are done -> Let's clean up */
+            pid_t ret;
+            close (pipefd1[1]);
+            close (pipefd2[0]);
+            ret = waitpid (cons_saver_pid, &status, 0);
+            (void) ret;
+            mc_global.tty.console_flag = '\0';
+        }
+        break;
+    default:
+        break;
+    }
+}
+
+#elif defined(__FreeBSD__)
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * FreeBSD support copyright (C) 2003 Alexander Serkov <serkov@ukrpost.net>.
+ * Support for screenmaps by Max Khon <fjoe@FreeBSD.org>
+ */
+
+static void
+console_init (void)
+{
+    if (mc_global.tty.console_flag != '\0')
+        return;
+
+    screen_info.size = sizeof (screen_info);
+    if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
+        return;
+
+    memset (&screen_shot, 0, sizeof (screen_shot));
+    screen_shot.xsize = screen_info.mv_csz;
+    screen_shot.ysize = screen_info.mv_rsz;
+    screen_shot.buf = g_try_malloc (screen_info.mv_csz * screen_info.mv_rsz * 2);
+    if (screen_shot.buf != NULL)
+        mc_global.tty.console_flag = '\001';
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+set_attr (unsigned attr)
+{
+    /*
+     * Convert color indices returned by SCRSHOT (red=4, green=2, blue=1)
+     * to indices for ANSI sequences (red=1, green=2, blue=4).
+     */
+    static const int color_map[8] = { 0, 4, 2, 6, 1, 5, 3, 7 };
+    int bc, tc;
+
+    tc = attr & 0xF;
+    bc = (attr >> 4) & 0xF;
+
+    printf ("\x1B[%d;%d;3%d;4%dm", (bc & 8) ? 5 : 25, (tc & 8) ? 1 : 22,
+            color_map[tc & 7], color_map[bc & 7]);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+console_restore (void)
+{
+    int i, last;
+
+    if (mc_global.tty.console_flag == '\0')
+        return;
+
+    cursor_to (0, 0);
+
+    /* restoring all content up to cursor position */
+    last = screen_info.mv_row * screen_info.mv_csz + screen_info.mv_col;
+    for (i = 0; i < last; ++i)
+    {
+        set_attr ((screen_shot.buf[i] >> 8) & 0xFF);
+        putc (screen_shot.buf[i] & 0xFF, stdout);
+    }
+
+    /* restoring cursor color */
+    set_attr ((screen_shot.buf[last] >> 8) & 0xFF);
+
+    fflush (stdout);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+console_shutdown (void)
+{
+    if (mc_global.tty.console_flag == '\0')
+        return;
+
+    g_free (screen_shot.buf);
+
+    mc_global.tty.console_flag = '\0';
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+console_save (void)
+{
+    int i;
+    scrmap_t map;
+    scrmap_t revmap;
+
+    if (mc_global.tty.console_flag == '\0')
+        return;
+
+    /* screen_info.size is already set in console_init() */
+    if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
+    {
+        console_shutdown ();
+        return;
+    }
+
+    /* handle console resize */
+    if (screen_info.mv_csz != screen_shot.xsize || screen_info.mv_rsz != screen_shot.ysize)
+    {
+        console_shutdown ();
+        console_init ();
+    }
+
+    if (ioctl (FD_OUT, CONS_SCRSHOT, &screen_shot) == -1)
+    {
+        console_shutdown ();
+        return;
+    }
+
+    if (ioctl (FD_OUT, GIO_SCRNMAP, &map) == -1)
+    {
+        console_shutdown ();
+        return;
+    }
+
+    for (i = 0; i < 256; i++)
+    {
+        char *p = memchr (map.scrmap, i, 256);
+        revmap.scrmap[i] = p ? p - map.scrmap : i;
+    }
+
+    for (i = 0; i < screen_shot.xsize * screen_shot.ysize; i++)
+    {
+        /* *INDENT-OFF* */
+        screen_shot.buf[i] = (screen_shot.buf[i] & 0xff00) 
+            | (unsigned char) revmap.scrmap[screen_shot.buf[i] & 0xff];
+        /* *INDENT-ON* */
+    }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+show_console_contents_freebsd (int starty, unsigned char begin_line, unsigned char end_line)
+{
+    int col, line;
+    char c;
+
+    if (mc_global.tty.console_flag == '\0')
+        return;
+
+    for (line = begin_line; line <= end_line; line++)
+    {
+        tty_gotoyx (starty + line - begin_line, 0);
+        for (col = 0; col < MIN (COLS, screen_info.mv_csz); col++)
+        {
+            c = screen_shot.buf[line * screen_info.mv_csz + col] & 0xFF;
+            tty_print_char (c);
+        }
+    }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+handle_console_freebsd (console_action_t action)
+{
+    switch (action)
+    {
+    case CONSOLE_INIT:
+        console_init ();
+        break;
+
+    case CONSOLE_DONE:
+        console_shutdown ();
+        break;
+
+    case CONSOLE_SAVE:
+        console_save ();
+        break;
+
+    case CONSOLE_RESTORE:
+        console_restore ();
+        break;
+    default:
+        break;
+    }
+}
+#endif /* __FreeBSD__ */
+
+/* --------------------------------------------------------------------------------------------- */
+/*** public functions ****************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+void
+show_console_contents (int starty, unsigned char begin_line, unsigned char end_line)
+{
+    tty_set_normal_attrs ();
+
+    if (look_for_rxvt_extensions ())
+    {
+        show_rxvt_contents (starty, begin_line, end_line);
+        return;
+    }
+#ifdef __linux__
+    show_console_contents_linux (starty, begin_line, end_line);
+#elif defined (__FreeBSD__)
+    show_console_contents_freebsd (starty, begin_line, end_line);
+#else
+    mc_global.tty.console_flag = '\0';
+#endif
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+handle_console (console_action_t action)
+{
+    (void) action;
+
+    if (look_for_rxvt_extensions ())
+        return;
+
+#ifdef __linux__
+    handle_console_linux (action);
+#elif defined (__FreeBSD__)
+    handle_console_freebsd (action);
+#endif
+}
+
+/* --------------------------------------------------------------------------------------------- */