/** * mds — A micro-display server * Copyright © 2014, 2015, 2016, 2017 Mattias Andrée (m@maandree.se) * * This program 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. * * This program 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 . */ #ifndef MDS_MDS_VT_H #define MDS_MDS_VT_H #include "mds-base.h" #include #include /** * Wait for confirmation that we may switch virtual terminal * * @param data Thread input parameter, will always be `NULL` * @return Thread return value, will always be `NULL` */ void *secondary_loop(void *data); /** * Perform a VT switch requested by the OS kernel * * @param leave_foreground Whether the display is leaving the foreground * @return Zero on success, -1 on error */ int switch_vt(int leave_foreground); /** * Handle the received message * * @return Zero on success, -1 on error */ int handle_message(void); /** * Handle a received `Command: get-vt` message * * @param client The value of the header `Client ID` in the received message * @param message The value of the header `Message ID` in the received message * @return Zero on success, -1 on error */ int handle_get_vt(const char *client, const char *message); /** * Handle a received `Command: configure-vt` message * * @param client The value of the header `Client ID` in the received message * @param message The value of the header `Message ID` in the received message * @param graphical The value of the header `Graphical` in the received message * @param exclusive The value of the header `Exclusive` in the received message * @return Zero on success, -1 on error */ int handle_configure_vt(const char *client, const char *message, const char *graphical, const char *exclusive); /** * This function is called when the kernel wants * to switch foreground virtual terminal * * @param signo The received signal number */ void received_switch_vt(int signo); /** * Get the index of the virtual terminal on which the display should be opened * * @return The index of the virtual terminal on which the display should be opened, -1 on error */ int select_vt(void); /** * Get the index of the next available virtual terminal * * @return -1 on error, 0 if the terminals are exhausted, otherwise the next terminal */ int vt_get_next_available(void); /** * Get the currently active virtual terminal * * @return -1 on error, otherwise the current terminal */ int vt_get_active(void); /** * Change currently active virtual terminal and wait for it to complete the switch * * @param vt The index of the terminal * @return Zero on success, -1 on error */ int vt_set_active(int vt); /** * Open a virtual terminal * * @param vt The index of the terminal * @param old_stat Output parameter for the old file stat for the terminal * @return The file descriptor for the terminal, -1 on error */ int vt_open(int vt, struct stat *restrict old_stat); /** * Close a virtual terminal * * @param vt The index of the terminal * @param old_stat The old file stat for the terminal */ void vt_close(int fd, struct stat *restrict old_stat); /** * Block or stop blocking other programs to open the a terminal * * @param fd:int File descriptor for the terminal * @param exclusive:int Whether to block other programs for using the terminal * @return :int Zero on success, -1 on error */ #define vt_set_exclusive(fd, exclusive)\ (ioctl(fd, (exclusive) ? TIOCEXCL : TIOCNXCL)) /** * Configure a terminal to be set to either graphical mode or text mode * * @param fd:int File descriptor for the terminal * @param graphical:int Whether to use graphical mode * @return :int Zero on success, -1 on error */ #define vt_set_graphical(fd, graphical)\ (ioctl(fd, KDSETMODE, (graphical) ? KD_GRAPHICS : KD_TEXT)) /** * Construct a virtual terminal mode that can be used in `vt_get_set_mode` * * @param vt_switch_control Whether we want to be able to block and delay VT switches * @param vt_leave_signal The signal that should be send to us we a process is trying * to switch terminal to another terminal * @param vt_enter_signal The signal that should be send to us we a process is trying * to switch terminal to our terminal * @param mode Output parameter */ void vt_construct_mode(int vt_switch_control, int vt_leave_signal, int vt_enter_signal, struct vt_mode *restrict mode); /** * Set or get the mode for a virtual terminal * * @param fd:int File descriptor for the terminal * @param set:int Whether to set the mode * @param mode:struct vt_mode* Input or outpur parameter for the mode * @return :int Zero on success, -1 on error */ #define vt_get_set_mode(fd, set, mode)\ (ioctl(fd, set ? VT_SETMODE : VT_GETMODE, mode)) /** * Block or temporarily block virtual terminal switch * * @param fd:int File descriptor for our terminal * @return :int Zero on success, -1 on error */ #define vt_stop_switch(fd)\ (ioctl(fd, VT_RELDISP, 0)) /** * Allow a temporarily block virtual terminal switch to continue * * @param fd:int File descriptor for our terminal * @return :int Zero on success, -1 on error */ #define vt_continue_switch(fd)\ (ioctl(fd, VT_RELDISP, 1)) /** * Accept a virtual terminal switch * * @param fd:int File descriptor for our terminal * @return :int Zero on success, -1 on error */ #define vt_accept_switch(fd)\ (ioctl(fd, VT_RELDISP, VT_ACKACQ)) #endif