sortix-mirror/dispd/client/session.c
Ralph Holmes 5d774cce1d Fix execl(3) sentinel undefined behaviour.
execl(3) and its variants use a sentinel to terminate the variadic
argument list, in the form of a null pointer constant of type pointer to
char. POSIX mandates that NULL is a null pointer constant of type
pointer to void, which is not of an equivalent type to that required by
execl(3) and its variants, resulting in undefined behaviour.

This commit casts all such instances of NULL to pointer to char type.
For consistency, it also adds const-qualification to any such instances
which had already been casted, and were not const-qualified.
2016-09-30 23:36:49 +02:00

122 lines
3.5 KiB
C

/*
* Copyright (c) 2012 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* session.c
* Handles session management.
*/
#include <sys/types.h>
#include <sys/display.h>
#include <sys/wait.h>
#include <error.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <dispd.h>
#include "session.h"
static const uint64_t ONE_AND_ONLY_DEVICE = 0;
static const uint64_t ONE_AND_ONLY_CONNECTOR = 0;
struct dispd_session* global_session = NULL;
bool dispd__session_initialize(int* argc, char*** argv)
{
(void) argc;
(void) argv;
size_t size = sizeof(struct dispd_session);
global_session = (struct dispd_session*) malloc(size);
if ( !global_session )
return false;
memset(global_session, 0, sizeof(*global_session));
global_session->device = ONE_AND_ONLY_DEVICE;
global_session->connector = ONE_AND_ONLY_CONNECTOR;
return true;
}
struct dispd_session* dispd_attach_default_session()
{
global_session->refcount++;
return global_session;
}
bool dispd_detach_session(struct dispd_session* session)
{
session->refcount--;
return true;
}
bool dispd_session_setup_game_rgba(struct dispd_session* session)
{
if ( session->is_rgba )
return true;
if ( session->current_window )
return false;
struct dispmsg_get_crtc_mode msg;
msg.msgid = DISPMSG_GET_CRTC_MODE;
msg.device = session->device;
msg.connector = session->connector;
if ( dispmsg_issue(&msg, sizeof(msg)) != 0 )
return false;
if ( !(msg.mode.control & 1) || msg.mode.fb_format != 32 )
{
pid_t childpid = fork();
if ( childpid < 0 )
return false;
if ( childpid )
{
int status;
waitpid(childpid, &status, 0);
return session->is_rgba = (WIFEXITED(status) && !WEXITSTATUS(status));
}
const char* chvideomode = "chvideomode";
#if 1
// TODO chvideomode currently launches --bpp 32 as a program...
execlp(chvideomode, chvideomode, (const char*) NULL);
#else
execlp(chvideomode, chvideomode,
"--bpp", "32",
"--show-graphics", "true",
"--show-text", "false",
(const char*) NULL);
#endif
perror(chvideomode);
exit(127);
}
// HACK: The console may be rendered asynchronously and it might still be
// rendering to the framebuffer, however this process is about to do
// bitmapped graphics to the framebuffer as well. Since there is no
// synchronization with the terminal except not writing to it, there
// is a small window where both are fighting for the framebuffer.
// We can resolve this issue by simply fsync()ing the terminal, which
// causes the scheduled console rendering to finish before returning.
int tty_fd = open("/dev/tty", O_WRONLY);
if ( 0 <= tty_fd )
{
fsync(tty_fd);
close(tty_fd);
}
return session->is_rgba = true;
}