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(__linux__) && defined(__i386__)
29 # include <fpu_control.h>
37 #include <simgear/compiler.h>
38 #include <simgear/structure/exception.hxx>
39 #include <simgear/debug/logstream.hxx>
46 #include "globals.hxx"
51 char *homedir = ::getenv( "HOME" );
52 char *hostname = ::getenv( "HOSTNAME" );
53 bool free_hostname = false;
55 // foreward declaration.
58 #if defined(__linux__) && defined(__i386__)
60 static void handleFPE (int);
65 fpu_control_t fpe_flags = 0;
66 _FPU_GETCW(fpe_flags);
67 // fpe_flags &= ~_FPU_MASK_IM; // invalid operation
68 // fpe_flags &= ~_FPU_MASK_DM; // denormalized operand
69 // fpe_flags &= ~_FPU_MASK_ZM; // zero-divide
70 // fpe_flags &= ~_FPU_MASK_OM; // overflow
71 // fpe_flags &= ~_FPU_MASK_UM; // underflow
72 // fpe_flags &= ~_FPU_MASK_PM; // precision (inexact result)
73 _FPU_SETCW(fpe_flags);
74 signal(SIGFPE, handleFPE);
81 SG_LOG(SG_GENERAL, SG_ALERT, "Floating point interrupt (SIGFPE)");
86 int main ( int argc, char **argv );
87 int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
88 LPSTR lpCmdLine, int nCmdShow) {
90 logbuf::has_no_console();
91 main( __argc, __argv );
97 #include <sys/sysmp.h>
101 * set the special "flush zero" bit (FS, bit 24) in the Control Status
102 * Register of the FPU of R4k and beyond so that the result of any
103 * underflowing operation will be clamped to zero, and no exception of
104 * any kind will be generated on the CPU. This has no effect on an
110 f.fc_word = get_fpc_csr();
111 f.fc_struct.flush = 1;
112 set_fpc_csr(f.fc_word);
116 static void fg_terminate() {
118 "Uncaught Exception: you should see a meaningful error message\n"
119 "here, but your GLUT (or SDL) library was apparently compiled\n"
120 "and/or linked without exception support. Please complain to\n"
126 int _bootstrap_OSInit;
128 // Main entry point; catch any exceptions that have made it this far.
129 int main ( int argc, char **argv ) {
131 #ifdef PTW32_STATIC_LIB
132 // Initialise static pthread win32 lib
133 pthread_win32_process_attach_np ();
135 _bootstrap_OSInit = 0;
137 #if defined(__linux__) && defined(__i386__)
138 // Enable floating-point exceptions for Linux/x86
140 #elif defined(__FreeBSD__)
141 // Ignore floating-point exceptions on FreeBSD
142 signal(SIGFPE, SIG_IGN);
145 signal(SIGPIPE, SIG_IGN);
151 // Bind all non-rendering threads to CPU1
152 // This will reduce the jitter caused by them to an absolute minimum,
153 // but it will only work with superuser authority.
154 if ( geteuid() == 0 )
156 sysmp(MP_CLOCK, 0); // bind the timer only to CPU0
157 sysmp(MP_ISOLATE, 1 ); // Isolate CPU1
158 sysmp(MP_NONPREEMPTIVE, 1 ); // disable process time slicing on CPU1
162 // Enable floating-point exceptions for Windows
163 #if defined( _MSC_VER ) && defined( DEBUG )
164 // Christian, we should document what this does
165 _control87( _EM_INEXACT, _MCW_EM );
168 #if defined( HAVE_BC5PLUS )
169 _control87(MCW_EM, MCW_EM); /* defined in float.h */
172 // FIXME: add other, more specific
175 std::set_terminate(fg_terminate);
176 atexit(fgExitCleanup);
177 fgMainInit(argc, argv);
178 } catch (const sg_throwable &t) {
179 // We must use cerr rather than
180 // logging, since logging may be
182 cerr << "Fatal error: " << t.getFormattedMessage() << endl;
183 if (!t.getOrigin().empty())
184 cerr << " (received from " << t.getOrigin() << ')' << endl;
186 } catch (const string &s) {
187 cerr << "Fatal error: " << s << endl;
189 } catch (const char *s) {
190 cerr << "Fatal error: " << s << endl;
193 cerr << "Unknown exception in the main loop. Aborting..." << endl;
195 perror("Possible cause");
201 // do some clean up on exit. Specifically we want to call alutExit()
202 // which happens in the sound manager destructor.
203 void fgExitCleanup() {
205 if (_bootstrap_OSInit != 0)
206 fgSetMouseCursor(MOUSE_CURSOR_POINTER);
210 if (free_hostname && hostname != NULL)