path: root/x11vnc/cleanup.c

/* -- cleanup.c -- */

#include "x11vnc.h"
#include "xwrappers.h"
#include "xdamage.h"
#include "remote.h"
#include "keyboard.h"
#include "scan.h"
#include "gui.h"
#include "solid.h"
#include "unixpw.h"
#include "sslcmds.h"
#include "sslhelper.h"
#include "connections.h"
#include "macosx.h"
#include "macosxCG.h"
#include "avahi.h"

/*
 * Exiting and error handling routines
 */

int trapped_xerror = 0;
int trapped_xioerror = 0;
int trapped_getimage_xerror = 0;
int trapped_record_xerror = 0;
XErrorEvent *trapped_xerror_event;

/* XXX CHECK BEFORE RELEASE */
int crash_debug = 0;

void clean_shm(int quick);
void clean_up_exit (int ret);
int trap_xerror(Display *d, XErrorEvent *error);
int trap_xioerror(Display *d);
int trap_getimage_xerror(Display *d, XErrorEvent *error);
char *xerror_string(XErrorEvent *error);
void initialize_crash_handler(void);
void initialize_signals(void);
void unset_signals(void);
void close_exec_fds(void);
int known_sigpipe_mode(char *s);


static int exit_flag = 0;
static int exit_sig = 0;

static void clean_icon_mode(void);
static int Xerror(Display *d, XErrorEvent *error);
static int XIOerr(Display *d);
static void crash_shell_help(void);
static void crash_shell(void);
static void interrupted (int sig);


void clean_shm(int quick) {
	int i, cnt = 0;

	/*
	 * to avoid deadlock, etc, under quick=1 we just delete the shm
	 * areas and leave the X stuff hanging.
	 */
	if (quick) {
		shm_delete(&scanline_shm);
		shm_delete(&fullscreen_shm);
		shm_delete(&snaprect_shm);
	} else {
		shm_clean(&scanline_shm, scanline);
		shm_clean(&fullscreen_shm, fullscreen);
		shm_clean(&snaprect_shm, snaprect);
	}

	/* 
	 * Here we have to clean up quite a few shm areas for all
	 * the possible tile row runs (40 for 1280), not as robust
	 * as one might like... sometimes need to run ipcrm(1). 
	 */
	for(i=1; i<=ntiles_x; i++) {
		if (i > tile_shm_count) {
			break;
		}
		if (quick) {
			shm_delete(&tile_row_shm[i]);
		} else {
			shm_clean(&tile_row_shm[i], tile_row[i]);
		}
		cnt++;
		if (single_copytile_count && i >= single_copytile_count) {
			break;
		}
	}
	if (!quiet && cnt > 0) {
		rfbLog("deleted %d tile_row polling images.\n", cnt);
	}
}

static void clean_icon_mode(void) {
	if (icon_mode && icon_mode_fh) {
		fprintf(icon_mode_fh, "quit\n");
		fflush(icon_mode_fh);
		fclose(icon_mode_fh);
		icon_mode_fh = NULL;
		if (icon_mode_file) {
			unlink(icon_mode_file);
			icon_mode_file = NULL;
		}
	}
}

/*
 * Normal exiting
 */
void clean_up_exit (int ret) {
	static int depth = 0;
	exit_flag = 1;

	if (depth++ > 2) {
		exit(ret);
	}

	if (icon_mode) {
		clean_icon_mode();
	}

	/* remove the shm areas: */
	clean_shm(0);

	stop_stunnel();
	if (use_openssl) {
		ssl_helper_pid(0, 0);	/* killall */
	}

	if (avahi) {
		avahi_cleanup();
	}
	if (ssh_pid > 0) {
		kill(ssh_pid, SIGTERM);
		ssh_pid = 0;
	}

#ifdef MACOSX
	if (client_connect_file) {
		if (strstr(client_connect_file, "/tmp/x11vnc-macosx-remote")
		    == client_connect_file) {
			unlink(client_connect_file);
		}
	}
	if (macosx_console) {
		macosxCG_fini();
	}
#endif

	if (! dpy) exit(ret);	/* raw_rb hack */

	/* X keyboard cleanups */
	delete_added_keycodes(0);

	if (clear_mods == 1) {
		clear_modifiers(0);
	} else if (clear_mods == 2) {
		clear_keys();
	} else if (clear_mods == 3) {
		clear_keys();
		clear_locks();
	}

	if (no_autorepeat) {
		autorepeat(1, 0);
	}
	if (use_solid_bg) {
		solid_bg(1);
	}
	if (ncache || ncache0) {
		kde_no_animate(1);
	}
	X_LOCK;
	XTestDiscard_wr(dpy);
#if LIBVNCSERVER_HAVE_LIBXDAMAGE
	if (xdamage) {
		XDamageDestroy(dpy, xdamage);
	}
#endif
#if LIBVNCSERVER_HAVE_LIBXTRAP
	if (trap_ctx) {
		XEFreeTC(trap_ctx);
	}
#endif
	/* XXX rdpy_ctrl, etc. cannot close w/o blocking */
	XCloseDisplay_wr(dpy);
	X_UNLOCK;

	fflush(stderr);
	exit(ret);
}

/* X11 error handlers */

static XErrorHandler   Xerror_def;
static XIOErrorHandler XIOerr_def;

int trap_xerror(Display *d, XErrorEvent *error) {
	trapped_xerror = 1;
	trapped_xerror_event = error;

	if (d) {} /* unused vars warning: */

	return 0;
}

int trap_xioerror(Display *d) {
	trapped_xioerror = 1;

	if (d) {} /* unused vars warning: */

	return 0;
}

int trap_getimage_xerror(Display *d, XErrorEvent *error) {
	trapped_getimage_xerror = 1;
	trapped_xerror_event = error;

	if (d) {} /* unused vars warning: */

	return 0;
}

static int Xerror(Display *d, XErrorEvent *error) {
	X_UNLOCK;

	if (getenv("X11VNC_PRINT_XERROR")) {
		fprintf(stderr, "Xerror: major_opcode: %d minor_opcode: %d error_code: %d\n",
		    error->request_code, error->minor_code, error->error_code);
	}

	if (xshm_opcode > 0 && error->request_code == xshm_opcode) {
		if (error->minor_code == X_ShmAttach) {
			char *dstr = DisplayString(dpy);
			fprintf(stderr, "\nX11 MIT Shared Memory Attach failed:\n");
			fprintf(stderr, "  Is your DISPLAY=%s on a remote machine?\n", dstr);
			if (strstr(dstr, "localhost:")) {
				fprintf(stderr, "  Note:   DISPLAY=localhost:N suggests a SSH X11 redir to a remote machine.\n");
			} else if (dstr[0] != ':') {
				fprintf(stderr, "  Note:   DISPLAY=hostname:N suggests a remote display.\n");
			}
			fprintf(stderr, "  Suggestion, use: x11vnc -display :0 ... for local display :0\n\n");
		}
	}

	interrupted(0);

	if (d) {} /* unused vars warning: */

	return (*Xerror_def)(d, error);
}

static int XIOerr(Display *d) {
	X_UNLOCK;
	interrupted(-1);

	if (d) {} /* unused vars warning: */

	return (*XIOerr_def)(d);
}

static char *xerrors[] = {
	"Success",
	"BadRequest",
	"BadValue",
	"BadWindow",
	"BadPixmap",
	"BadAtom",
	"BadCursor",
	"BadFont",
	"BadMatch",
	"BadDrawable",
	"BadAccess",
	"BadAlloc",
	"BadColor",
	"BadGC",
	"BadIDChoice",
	"BadName",
	"BadLength",
	"BadImplementation",
	"unknown"
};
static int xerrors_max = BadImplementation;

char *xerror_string(XErrorEvent *error) {
	int index = -1;
	if (error) {
		index = (int) error->error_code;
	}
	if (0 <= index && index <= xerrors_max) {
		return xerrors[index];
	} else {
		return xerrors[xerrors_max+1];
	}
}

static char *crash_stack_command1 = NULL;
static char *crash_stack_command2 = NULL;
static char *crash_debug_command = NULL;

void initialize_crash_handler(void) {
	int pid = program_pid;
	crash_stack_command1 = (char *) malloc(1000);
	crash_stack_command2 = (char *) malloc(1000);
	crash_debug_command =  (char *) malloc(1000);

	snprintf(crash_stack_command1, 500, "echo where > /tmp/gdb.%d;"
	    " env PATH=$PATH:/usr/local/bin:/usr/sfw/bin:/usr/bin"
	    " gdb -x /tmp/gdb.%d -batch -n %s %d;"
	    " rm -f /tmp/gdb.%d", pid, pid, program_name, pid, pid);
	snprintf(crash_stack_command2, 500, "pstack %d", program_pid);
	
	snprintf(crash_debug_command, 500, "gdb %s %d", program_name, pid);
}

static void crash_shell_help(void) {
	int pid = program_pid;
	fprintf(stderr, "\n");
	fprintf(stderr, "   *** Welcome to the x11vnc crash shell! ***\n");
	fprintf(stderr, "\n");
	fprintf(stderr, "PROGRAM: %s  PID: %d\n", program_name, pid);
	fprintf(stderr, "\n");
	fprintf(stderr, "POSSIBLE DEBUGGER COMMAND:\n");
	fprintf(stderr, "\n");
	fprintf(stderr, "  %s\n", crash_debug_command);
	fprintf(stderr, "\n");
	fprintf(stderr, "Press \"q\" to quit.\n");
	fprintf(stderr, "Press \"h\" or \"?\" for this help.\n");
	fprintf(stderr, "Press \"s\" to try to run some commands to"
	    " show a stack trace (gdb/pstack).\n");
	fprintf(stderr, "\n");
	fprintf(stderr, "Anything else is passed to -Q query function.\n");
	fprintf(stderr, "\n");
}

static void crash_shell(void) {
	char qry[1000], cmd[1000], line[1000];
	char *str, *p;

	crash_shell_help();
	fprintf(stderr, "\ncrash> ");
	while (fgets(line, 1000, stdin) != NULL) {
		str = lblanks(line);

		p = str;
		while(*p) {
			if (*p == '\n') {
				*p = '\0';
			}
			p++;
		}

		if (*str == 'q' && *(str+1) == '\0') {
			fprintf(stderr, "quiting.\n");
			return;
		} else if (*str == 'h' && *(str+1) == '\0') {
			crash_shell_help();
		} else if (*str == '?' && *(str+1) == '\0') {
			crash_shell_help();
		} else if (*str == 's' && *(str+1) == '\0') {
			sprintf(cmd, "sh -c '(%s) &'", crash_stack_command1);
			/* crash */
			if (no_external_cmds || !cmd_ok("crash")) {
				fprintf(stderr, "\nno_external_cmds=%d\n",
				    no_external_cmds);
				goto crash_prompt;
			}
			fprintf(stderr, "\nrunning:\n\t%s\n\n",
			    crash_stack_command1);
			system(cmd);
			usleep(1000*1000);

			sprintf(cmd, "sh -c '(%s) &'", crash_stack_command2);
			fprintf(stderr, "\nrunning:\n\t%s\n\n",
			    crash_stack_command2);
			system(cmd);
			usleep(1000*1000);
		} else {
			snprintf(qry, 1000, "qry=%s", str);
			p = process_remote_cmd(qry, 1);
			fprintf(stderr, "\n\nresult:\n%s\n", p);
			free(p);
		}
		
crash_prompt:
		fprintf(stderr, "crash> ");
	}
}

/*
 * General problem handler
 */
static void interrupted (int sig) {
	exit_sig = sig;
	if (exit_flag) {
		fprintf(stderr, "extra[%d] signal: %d\n", exit_flag, sig);
		exit_flag++;
		if (use_threads) {
			usleep2(250 * 1000);
		} else if (exit_flag <= 2) {
			return;
		}
		exit(4);
	}
	exit_flag++;
	if (sig == 0) {
		fprintf(stderr, "caught X11 error:\n");
		if (crash_debug) { crash_shell(); }
	} else if (sig == -1) {
		fprintf(stderr, "caught XIO error:\n");
	} else {
		fprintf(stderr, "caught signal: %d\n", sig);
	}
	if (sig == SIGINT) {
		shut_down = 1;
		return;
	}

	if (crash_debug) {
		crash_shell();
	}

	X_UNLOCK;

	if (icon_mode) {
		clean_icon_mode();
	}
	/* remove the shm areas with quick=1: */
	clean_shm(1);

	if (sig == -1) {
		/* not worth trying any more cleanup, X server probably gone */
		exit(3);
	}

	/* X keyboard cleanups */
	delete_added_keycodes(0);

	if (clear_mods == 1) {
		clear_modifiers(0);
	} else if (clear_mods == 2) {
		clear_keys();
	} else if (clear_mods == 3) {
		clear_keys();
		clear_locks();
	}
	if (no_autorepeat) {
		autorepeat(1, 0);
	}
	if (use_solid_bg) {
		solid_bg(1);
	}
	if (ncache || ncache0) {
		kde_no_animate(1);
	}
	stop_stunnel();

	if (crash_debug) {
		crash_shell();
	}

	if (sig) {
		exit(2);
	}
}

static void ignore_sigs(char *list) {
	char *str, *p;
	int ignore = 1;
	if (list == NULL || *list == '\0') {
		return;
	}
	str = strdup(list);
	p = strtok(str, ":,");

#define SETSIG(x, y) \
	if (strstr(p, x)) { \
		if (ignore) { \
			signal(y, SIG_IGN); \
		} else { \
			signal(y, interrupted); \
		} \
	}

#ifdef SIG_IGN
	while (p) {
		if (!strcmp(p, "ignore")) {
			ignore = 1;
		} else if (!strcmp(p, "exit")) {
			ignore = 0;
		}
		/* Take off every 'sig' ;-) */
#ifdef SIGHUP
		SETSIG("HUP", SIGHUP);
#endif
#ifdef SIGINT
		SETSIG("INT", SIGINT);
#endif
#ifdef SIGQUIT
		SETSIG("QUIT", SIGQUIT);
#endif
#ifdef SIGTRAP
		SETSIG("TRAP", SIGTRAP);
#endif
#ifdef SIGABRT
		SETSIG("ABRT", SIGABRT);
#endif
#ifdef SIGBUS
		SETSIG("BUS", SIGBUS);
#endif
#ifdef SIGFPE
		SETSIG("FPE", SIGFPE);
#endif
#ifdef SIGSEGV
		SETSIG("SEGV", SIGSEGV);
#endif
#ifdef SIGPIPE
		SETSIG("PIPE", SIGPIPE);
#endif
#ifdef SIGTERM
		SETSIG("TERM", SIGTERM);
#endif
#ifdef SIGUSR1
		SETSIG("USR1", SIGUSR1);
#endif
#ifdef SIGUSR2
		SETSIG("USR2", SIGUSR2);
#endif
#ifdef SIGCONT
		SETSIG("CONT", SIGCONT);
#endif
#ifdef SIGSTOP
		SETSIG("STOP", SIGSTOP);
#endif
#ifdef SIGTSTP
		SETSIG("TSTP", SIGTSTP);
#endif
		p = strtok(NULL, ":,");
	}
#endif	/* SIG_IGN */
	free(str);
}

/* signal handlers */
void initialize_signals(void) {
	signal(SIGHUP,  interrupted);
	signal(SIGINT,  interrupted);
	signal(SIGQUIT, interrupted);
	signal(SIGABRT, interrupted);
	signal(SIGTERM, interrupted);
	signal(SIGBUS,  interrupted);
	signal(SIGSEGV, interrupted);
	signal(SIGFPE,  interrupted);

	if (!sigpipe || *sigpipe == '\0' || !strcmp(sigpipe, "skip")) {
		;
	} else if (strstr(sigpipe, "ignore:") == sigpipe) {
		ignore_sigs(sigpipe);
	} else if (strstr(sigpipe, "exit:") == sigpipe) {
		ignore_sigs(sigpipe);
	} else if (!strcmp(sigpipe, "ignore")) {
#ifdef SIG_IGN
		signal(SIGPIPE, SIG_IGN);
#endif
	} else if (!strcmp(sigpipe, "exit")) {
		rfbLog("initialize_signals: will exit on SIGPIPE\n");
		signal(SIGPIPE, interrupted);
	}

#if NO_X11
	return;
#else
	X_LOCK;
	Xerror_def = XSetErrorHandler(Xerror);
	XIOerr_def = XSetIOErrorHandler(XIOerr);
	X_UNLOCK;
#endif	/* NO_X11 */
}

void unset_signals(void) {
	signal(SIGHUP,  SIG_DFL);
	signal(SIGINT,  SIG_DFL);
	signal(SIGQUIT, SIG_DFL);
	signal(SIGABRT, SIG_DFL);
	signal(SIGTERM, SIG_DFL);
	signal(SIGBUS,  SIG_DFL);
	signal(SIGSEGV, SIG_DFL);
	signal(SIGFPE,  SIG_DFL);
	signal(SIGPIPE, SIG_DFL);
}

void close_exec_fds(void) {
	int fd;
#ifdef FD_CLOEXEC
	for (fd = 3; fd < 64; fd++) {
		int flags = fcntl(fd, F_GETFD);
		if (flags != -1) {
			flags |= FD_CLOEXEC;
			fcntl(fd, F_SETFD, flags);
		}
	}
#endif
}

int known_sigpipe_mode(char *s) {
/*
 * skip, ignore, exit
 */
	if (strstr(s, "ignore:") == s) {
		return 1;
	}
	if (strstr(s, "exit:") == s) {
		return 1;
	}
	if (strcmp(s, "skip") && strcmp(s, "ignore") && 
	    strcmp(s, "exit")) {
		return 0;
	} else {
		return 1;
	}
}