1 // bootstrap.cxx -- bootstrap routines: main()
3 // Written by Curtis Olson, started May 1997.
5 // Copyright (C) 1997 - 2002 Curtis L. Olson - http://www.flightgear.org/~curt
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
28 #if defined(HAVE_FEENABLEEXCEPT)
33 #elif defined(__linux__) && defined(__i386__)
34 # include <fpu_control.h>
42 #include <simgear/compiler.h>
43 #include <simgear/structure/exception.hxx>
44 #include <simgear/debug/logstream.hxx>
45 #include <simgear/math/SGMath.hxx>
53 #include "globals.hxx"
54 #include "fg_props.hxx"
55 #include "fgviewer.hxx"
61 char homepath[256] = "";
62 char * homedir = homepath;
63 char *hostname = ::getenv( "COMPUTERNAME" );
65 char *homedir = ::getenv( "HOME" );
66 char *hostname = ::getenv( "HOSTNAME" );
68 bool free_hostname = false;
70 // foreward declaration.
73 static bool fpeAbort = false;
74 static void initFPE();
76 #if defined(HAVE_FEENABLEEXCEPT)
77 static void handleFPE(int);
82 int except = fegetexcept();
83 feenableexcept(except | FE_DIVBYZERO | FE_INVALID);
85 signal(SIGFPE, handleFPE);
89 static void handleFPE(int)
91 feclearexcept(FE_ALL_EXCEPT);
92 signal(SIGFPE, handleFPE);
94 #elif defined(__linux__) && defined(__i386__)
96 static void handleFPE(int);
100 fpu_control_t fpe_flags = 0;
101 _FPU_GETCW(fpe_flags);
102 // fpe_flags &= ~_FPU_MASK_IM; // invalid operation
103 // fpe_flags &= ~_FPU_MASK_DM; // denormalized operand
104 // fpe_flags &= ~_FPU_MASK_ZM; // zero-divide
105 // fpe_flags &= ~_FPU_MASK_OM; // overflow
106 // fpe_flags &= ~_FPU_MASK_UM; // underflow
107 // fpe_flags &= ~_FPU_MASK_PM; // precision (inexact result)
108 _FPU_SETCW(fpe_flags);
109 signal(SIGFPE, handleFPE);
116 SG_LOG(SG_GENERAL, SG_ALERT, "Floating point interrupt (SIGFPE)");
119 static void initFPE()
125 int main ( int argc, char **argv );
126 int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
127 LPSTR lpCmdLine, int nCmdShow) {
129 logbuf::has_no_console();
130 main( __argc, __argv );
136 #include <sys/sysmp.h>
140 * set the special "flush zero" bit (FS, bit 24) in the Control Status
141 * Register of the FPU of R4k and beyond so that the result of any
142 * underflowing operation will be clamped to zero, and no exception of
143 * any kind will be generated on the CPU. This has no effect on an
149 f.fc_word = get_fpc_csr();
150 f.fc_struct.flush = 1;
151 set_fpc_csr(f.fc_word);
155 static void fg_terminate() {
157 "Uncaught Exception: you should see a meaningful error message\n"
158 "here, but your GLUT (or SDL) library was apparently compiled\n"
159 "and/or linked without exception support. Please complain to\n"
165 int _bootstrap_OSInit;
167 // Main entry point; catch any exceptions that have made it this far.
168 int main ( int argc, char **argv ) {
170 // Windows has no $HOME aka %HOME%, so we have to construct the full path.
171 // make sure it fits into the buffer. Max. path length is 255, but who knows
172 // what's in these environment variables?
173 homepath[sizeof(homepath)-1] = 0;
174 strncpy( homepath, ::getenv("APPDATA"), sizeof(homepath)-1 );
175 strncat( homepath, "\\flightgear.org", sizeof(homepath)-strlen(homepath)-1 );
178 #ifdef PTW32_STATIC_LIB
179 // Initialise static pthread win32 lib
180 pthread_win32_process_attach_np ();
182 _bootstrap_OSInit = 0;
184 #if defined(__FreeBSD__)
185 // Ignore floating-point exceptions on FreeBSD
186 signal(SIGFPE, SIG_IGN);
188 // Maybe Enable floating-point exceptions on Linux
189 for (int i = 0; i < argc; ++i) {
190 if (!strcmp("--enable-fpe", argv[i])) {
198 signal(SIGPIPE, SIG_IGN);
204 // Bind all non-rendering threads to CPU1
205 // This will reduce the jitter caused by them to an absolute minimum,
206 // but it will only work with superuser authority.
207 if ( geteuid() == 0 )
209 sysmp(MP_CLOCK, 0); // bind the timer only to CPU0
210 sysmp(MP_ISOLATE, 1 ); // Isolate CPU1
211 sysmp(MP_NONPREEMPTIVE, 1 ); // disable process time slicing on CPU1
215 // Enable floating-point exceptions for Windows
216 #if defined( _MSC_VER ) && defined( DEBUG )
217 // Christian, we should document what this does
218 _control87( _EM_INEXACT, _MCW_EM );
221 #if defined( HAVE_BC5PLUS )
222 _control87(MCW_EM, MCW_EM); /* defined in float.h */
224 bool fgviewer = false;
225 for (int i = 0; i < argc; ++i) {
226 if (!strcmp("--fgviewer", argv[i])) {
232 // FIXME: add other, more specific
235 std::set_terminate(fg_terminate);
236 atexit(fgExitCleanup);
238 fgviewerMain(argc, argv);
240 fgMainInit(argc, argv);
243 } catch (const sg_throwable &t) {
244 // We must use cerr rather than
245 // logging, since logging may be
247 cerr << "Fatal error: " << t.getFormattedMessage() << endl;
248 if (std::strlen(t.getOrigin()) != 0)
249 cerr << " (received from " << t.getOrigin() << ')' << endl;
251 } catch (const string &s) {
252 cerr << "Fatal error: " << s << endl;
254 } catch (const char *s) {
255 cerr << "Fatal error: " << s << endl;
258 cerr << "Unknown exception in the main loop. Aborting..." << endl;
260 perror("Possible cause");
266 // do some clean up on exit. Specifically we want to call alutExit()
267 // which happens in the sound manager destructor.
268 void fgExitCleanup() {
270 if (_bootstrap_OSInit != 0)
271 fgSetMouseCursor(MOUSE_CURSOR_POINTER);
275 if (free_hostname && hostname != NULL)