-// ExternalPipe.hxx -- a "pipe" interface to an external flight dynamics model
+// ExternalPipe.cxx -- a "pipe" interface to an external flight dynamics model
//
// Written by Curtis Olson, started March 2003.
//
# include <config.h>
#endif
-#if defined( HAVE_SYS_TYPES_H ) && defined( HAVE_SYS_STAT_H )
+#ifdef HAVE_MKFIFO
# include <sys/types.h> // mkfifo() open() umask()
# include <sys/stat.h> // mkfifo() open() umask()
+# include <errno.h> // perror()
# include <fcntl.h> // open()
# include <unistd.h> // unlink()
#endif
#include "ExternalPipe.hxx"
+static const int MAX_BUF = 32768;
+
FGExternalPipe::FGExternalPipe( double dt, string name ) {
valid = true;
+ last_weight = 0.0;
+ last_cg_offset = -9999.9;
- buf = new char[sizeof(ctrls) + 1];
-
- cout << "dt = " << dt << endl;
+ buf = new char[MAX_BUF];
-#if defined( HAVE_SYS_TYPES_H ) && defined( HAVE_SYS_STAT_H )
+#ifdef HAVE_MKFIFO
fifo_name_1 = name + "1";
fifo_name_2 = name + "2";
if ( result == -1 ) {
SG_LOG( SG_IO, SG_ALERT, "Unable to create named pipe: "
<< fifo_name_1 );
- valid = false;
+ perror( "ExternalPipe()" );
}
result = mkfifo( fifo_name_2.c_str(), 0644 );
if ( result == -1 ) {
SG_LOG( SG_IO, SG_ALERT, "Unable to create named pipe: "
<< fifo_name_2 );
- valid = false;
+ perror( "ExternalPipe()" );
}
pd1 = open( fifo_name_1.c_str(), O_RDWR );
- cout << "pd1 = " << pd1 << endl;
if ( pd1 == -1 ) {
SG_LOG( SG_IO, SG_ALERT, "Unable to open named pipe: " << fifo_name_1 );
valid = false;
}
pd2 = open( fifo_name_2.c_str(), O_RDWR );
- cout << "pd2 = " << pd2 << endl;
if ( pd2 == -1 ) {
SG_LOG( SG_IO, SG_ALERT, "Unable to open named pipe: " << fifo_name_2 );
valid = false;
SG_LOG( SG_IO, SG_INFO, "Closing up the ExternalPipe." );
-#if defined( HAVE_SYS_TYPES_H ) && defined( HAVE_SYS_STAT_H )
+#ifdef HAVE_MKFIFO
// close
int result;
result = close( pd1 );
if ( result == -1 ) {
SG_LOG( SG_IO, SG_ALERT, "Unable to close named pipe: "
<< fifo_name_1 );
+ perror( "~FGExternalPipe()" );
}
result = close( pd2 );
if ( result == -1 ) {
SG_LOG( SG_IO, SG_ALERT, "Unable to close named pipe: "
<< fifo_name_2 );
+ perror( "~FGExternalPipe()" );
+ }
+#endif
+}
+
+
+static int write_fifo( char cmd_type, int pd, char *cmd, int len ) {
+#ifdef HAVE_MKFIFO
+ char *buf = new char[len + 3];
+
+ // write 2 byte command length + command type + command
+ char hi = (len + 1) / 256;
+ char lo = (len + 1) - (hi * 256);
+
+ buf[0] = hi;
+ buf[1] = lo;
+ buf[2] = cmd_type;
+
+ // strncpy( buf + 3, cmd, len );
+ memcpy( buf + 3, cmd, len );
+
+ if ( cmd_type == '1' ) {
+ // cout << "writing '" << cmd << "'" << endl;
+ } else if ( cmd_type == '2' ) {
+ // cout << "writing controls packet" << endl;
+ } else {
+ // cout << "writing unknown command?" << endl;
+ }
+
+ // for ( int i = 0; i < len + 3; ++i ) {
+ // cout << " " << (int)buf[i];
+ // }
+ // cout << endl;
+
+ int result = ::write( pd, buf, len + 3 );
+ if ( result == -1 ) {
+ perror( "write_fifo()" );
+ SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << pd );
}
+ // cout << "wrote " << len + 3 << " bytes." << endl;
+
+ delete [] buf;
+
+ return result;
+#else
+ return 0;
#endif
}
double ground = fgGetDouble( "/environment/ground-elevation-m" );
double heading = fgGetDouble("/sim/presets/heading-deg");
double speed = fgGetDouble( "/sim/presets/airspeed-kt" );
+ double weight = fgGetDouble( "/sim/aircraft-weight-lbs" );
+ double cg_offset = fgGetDouble( "/sim/aircraft-cg-offset-inches" );
-#if defined( HAVE_SYS_TYPES_H ) && defined( HAVE_SYS_STAT_H )
+#ifdef HAVE_MKFIFO
char cmd[256];
int result;
- sprintf( cmd, "1longitude-deg=%.8f", lon );
- result = std::write( pd1, cmd, strlen(cmd) );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << fifo_name_1 );
- }
+ sprintf( cmd, "longitude-deg=%.8f", lon );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
- sprintf( cmd, "1latitude-deg=%.8f", lat );
- result = ::write( pd1, cmd, strlen(cmd) );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << fifo_name_1 );
- }
+ sprintf( cmd, "latitude-deg=%.8f", lat );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
- sprintf( cmd, "1altitude-ft=%.8f", alt );
- result = std::write( pd1, cmd, strlen(cmd) );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << fifo_name_1 );
- }
+ sprintf( cmd, "altitude-ft=%.8f", alt );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
- sprintf( cmd, "1ground-m=%.8f", ground );
- result = std::write( pd1, cmd, strlen(cmd) );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << fifo_name_1 );
- }
+ sprintf( cmd, "ground-m=%.8f", ground );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
- sprintf( cmd, "1speed-kts=%.8f", speed );
- result = std::write( pd1, cmd, strlen(cmd) );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << fifo_name_1 );
+ sprintf( cmd, "speed-kts=%.8f", speed );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
+
+ sprintf( cmd, "heading-deg=%.8f", heading );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
+
+ if ( weight > 1000.0 ) {
+ sprintf( cmd, "aircraft-weight-lbs=%.2f", weight );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
}
+ last_weight = weight;
- sprintf( cmd, "1heading-deg=%.8f", heading );
- result = std::write( pd1, cmd, strlen(cmd) );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << fifo_name_1 );
+ if ( cg_offset > -5.0 || cg_offset < 5.0 ) {
+ sprintf( cmd, "aircraft-cg-offset-inches=%.2f", cg_offset );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
}
+ last_cg_offset = cg_offset;
- SG_LOG( SG_IO, SG_INFO, "before sending reset command." );
+ SG_LOG( SG_IO, SG_ALERT, "before sending reset command." );
if( fgGetBool("/sim/presets/onground") ) {
- sprintf( cmd, "1reset=ground" );
+ sprintf( cmd, "reset=ground" );
} else {
- sprintf( cmd, "1reset=air" );
- }
- result = std::write( pd1, cmd, strlen(cmd) );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: " << fifo_name_1 );
+ sprintf( cmd, "reset=air" );
}
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
- SG_LOG( SG_IO, SG_INFO, "Remote FDM init() finished." );
+ SG_LOG( SG_IO, SG_ALERT, "Remote FDM init() finished." );
#endif
}
// Run an iteration of the EOM.
void FGExternalPipe::update( double dt ) {
-#if defined( HAVE_SYS_TYPES_H ) && defined( HAVE_SYS_STAT_H )
+#ifdef HAVE_MKFIFO
// SG_LOG( SG_IO, SG_INFO, "Start FGExternalPipe::udpate()" );
int length;
int result;
-
+
if ( is_suspended() ) {
return;
}
int iterations = _calc_multiloop(dt);
+ double weight = fgGetDouble( "/sim/aircraft-weight-lbs" );
+ static double last_weight = 0.0;
+ if ( fabs( weight - last_weight ) > 0.01 ) {
+ char cmd[256];
+ sprintf( cmd, "aircraft-weight-lbs=%.2f", weight );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
+ }
+ last_weight = weight;
+
+ double cg_offset = fgGetDouble( "/sim/aircraft-cg-offset-inches" );
+ if ( fabs( cg_offset - last_cg_offset ) > 0.01 ) {
+ char cmd[256];
+ sprintf( cmd, "aircraft-cg-offset-inches=%.2f", cg_offset );
+ result = write_fifo( '1', pd1, cmd, strlen(cmd) );
+ }
+ last_cg_offset = cg_offset;
+
// Send control positions to remote fdm
length = sizeof(ctrls);
- FGProps2NetCtrls( &ctrls, false );
+ FGProps2NetCtrls( &ctrls, true, false );
char *ptr = buf;
- *ptr = '2';
- ptr++;
*((int *)ptr) = iterations;
+ // cout << "iterations = " << iterations << endl;
ptr += sizeof(int);
memcpy( ptr, (char *)(&ctrls), length );
- result = std::write( pd1, buf, length + 1 );
- if ( result == -1 ) {
- SG_LOG( SG_IO, SG_ALERT, "Write error to named pipe: "
- << fifo_name_1 );
- }
- // cout << " wrote to pipe" << endl;
+ // cout << "writing control structure, size = "
+ // << length + sizeof(int) << endl;
+
+ result = write_fifo( '2', pd1, buf, length + sizeof(int) );
+ // Read fdm values
length = sizeof(fdm);
- result = std::read( pd2, (char *)(& fdm), length );
+ // cout << "about to read fdm data from remote fdm." << endl;
+ result = read( pd2, (char *)(& fdm), length );
if ( result == -1 ) {
SG_LOG( SG_IO, SG_ALERT, "Read error from named pipe: "
<< fifo_name_2 );
+ } else {
+ // cout << " read successful." << endl;
}
FGNetFDM2Props( &fdm, false );
- // cout << "read from pipe" << endl;
-
- // SG_LOG( SG_IO, SG_INFO, " End FGExternalPipe::udpate()" );
#endif
}