Tweaks to endianess support.

diff --git a/simgear/io/Makefile.am b/simgear/io/Makefile.am
index 5b439944ce1fc0db7479ca2c49160922de96fd70..d6d53c4cfdcbeab46d883f88f628a28147836863 100644 (file)
--- a/simgear/io/Makefile.am
+++ b/simgear/io/Makefile.am
@@ -20,10 +20,15 @@ libsgio_a_SOURCES = \
 
 INCLUDES += -I$(top_srcdir)
 
-noinst_PROGRAMS = socktest
+noinst_PROGRAMS = socktest lowtest
 
 socktest_SOURCES = socktest.cxx
 
 socktest_LDADD = \
        $(top_builddir)/simgear/io/libsgio.a \
-       $(top_builddir)/simgear/debug/libsgdebug.a 
\ No newline at end of file
+       $(top_builddir)/simgear/debug/libsgdebug.a
+
+lowtest_SOURCES = lowtest.cxx
+
+lowtest_LDADD = \
+       $(top_builddir)/simgear/io/libsgio.a 
\ No newline at end of file

diff --git a/simgear/io/lowlevel.cxx b/simgear/io/lowlevel.cxx
index 54ba40c365cb2b2371844801c2c6113e29f1ed89..57a6e0f6fb210dfa36e981fa357aed1c6807a932 100644 (file)
--- a/simgear/io/lowlevel.cxx
+++ b/simgear/io/lowlevel.cxx
@@ -1,4 +1,4 @@
-// lowlevel.hxx -- routines to handle lowlevel compressed binary IO of
+// lowlevel.cxx -- routines to handle lowlevel compressed binary IO of
 //                 various datatypes
 //
 // Shamelessly adapted from plib (plib.sourceforge.net) January 2001
@@ -21,10 +21,11 @@
 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 //
 // $Id$
-//
+
 
 #include "lowlevel.hxx" 
 
+
 static int  read_error = false ;
 static int write_error = false ;
 
@@ -33,36 +34,7 @@ void sgClearWriteError() { write_error = false; }
 int sgReadError() { return  read_error ; }
 int sgWriteError() { return write_error ; }
 
-static const int sgEndianTest = 1;
-#define sgIsLittleEndian (*((char *) &sgEndianTest ) != 0)
-#define sgIsBigEndian    (*((char *) &sgEndianTest ) == 0)
-
-static inline void sgEndianSwap(unsigned short *x) {
-    *x =
-        (( *x >>  8 ) & 0x00FF ) | 
-        (( *x <<  8 ) & 0xFF00 ) ;
-}
-  
-static inline void sgEndianSwap(unsigned int *x) {
-    *x =
-        (( *x >> 24 ) & 0x000000FF ) | 
-        (( *x >>  8 ) & 0x0000FF00 ) | 
-        (( *x <<  8 ) & 0x00FF0000 ) | 
-        (( *x << 24 ) & 0xFF000000 ) ;
-}
-  
-static inline void sgEndianSwap(unsigned long long *x) {
-    *x =
-        (( *x >> 56 ) & 0x00000000000000FFULL ) | 
-        (( *x >> 40 ) & 0x000000000000FF00ULL ) | 
-        (( *x >> 24 ) & 0x0000000000FF0000ULL ) | 
-        (( *x >>  8 ) & 0x00000000FF000000ULL ) | 
-        (( *x <<  8 ) & 0x000000FF00000000ULL ) | 
-        (( *x << 24 ) & 0x0000FF0000000000ULL ) |
-        (( *x << 40 ) & 0x00FF000000000000ULL ) |
-        (( *x << 56 ) & 0xFF00000000000000ULL ) ;
-}
-  
+
 void sgReadChar ( gzFile fd, char *var )
 {
     if ( gzread ( fd, var, sizeof(char) ) != sizeof(char) ) {
@@ -84,7 +56,7 @@ void sgReadFloat ( gzFile fd, float *var )
     if ( gzread ( fd, var, sizeof(float) ) != sizeof(float) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)var);
     }
 }
@@ -92,7 +64,7 @@ void sgReadFloat ( gzFile fd, float *var )
 
 void sgWriteFloat ( gzFile fd, const float var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(float) ) != sizeof(float) ) {
@@ -106,7 +78,7 @@ void sgReadDouble ( gzFile fd, double *var )
     if ( gzread ( fd, var, sizeof(double) ) != sizeof(double) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned long long*)var);
     }
 }
@@ -114,7 +86,7 @@ void sgReadDouble ( gzFile fd, double *var )
 
 void sgWriteDouble ( gzFile fd, const double var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned long long*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(double) ) != sizeof(double) ) {
@@ -128,7 +100,7 @@ void sgReadUInt ( gzFile fd, unsigned int *var )
     if ( gzread ( fd, var, sizeof(unsigned int) ) != sizeof(unsigned int) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)var);
     }
 }
@@ -136,7 +108,7 @@ void sgReadUInt ( gzFile fd, unsigned int *var )
 
 void sgWriteUInt ( gzFile fd, const unsigned int var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(unsigned int) )
@@ -152,7 +124,7 @@ void sgReadInt ( gzFile fd, int *var )
     if ( gzread ( fd, var, sizeof(int) ) != sizeof(int) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)var);
     }
 }
@@ -160,7 +132,7 @@ void sgReadInt ( gzFile fd, int *var )
 
 void sgWriteInt ( gzFile fd, const int var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(int) ) != sizeof(int) ) {
@@ -174,7 +146,7 @@ void sgReadLong ( gzFile fd, long int *var )
     if ( gzread ( fd, var, sizeof(long int) ) != sizeof(long int) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)var);
     }
 }
@@ -182,7 +154,7 @@ void sgReadLong ( gzFile fd, long int *var )
 
 void sgWriteLong ( gzFile fd, const long int var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned int*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(long int) )
@@ -198,7 +170,7 @@ void sgReadLongLong ( gzFile fd, long long int *var )
     if ( gzread ( fd, var, sizeof(long long int) ) != sizeof(long long int) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned long long int*)var);
     }
 }
@@ -206,7 +178,7 @@ void sgReadLongLong ( gzFile fd, long long int *var )
 
 void sgWriteLongLong ( gzFile fd, const long long int var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned long long*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(long long int) )
@@ -222,7 +194,7 @@ void sgReadUShort ( gzFile fd, unsigned short *var )
     if ( gzread ( fd, var, sizeof(unsigned short) ) != sizeof(unsigned short) ){
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned short int*)var);
     }
 }
@@ -230,7 +202,7 @@ void sgReadUShort ( gzFile fd, unsigned short *var )
 
 void sgWriteUShort ( gzFile fd, const unsigned short var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned short*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(unsigned short) )
@@ -246,7 +218,7 @@ void sgReadShort ( gzFile fd, short *var )
     if ( gzread ( fd, var, sizeof(short) ) != sizeof(short) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned short int*)var);
     }
 }
@@ -254,7 +226,7 @@ void sgReadShort ( gzFile fd, short *var )
 
 void sgWriteShort ( gzFile fd, const short var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         sgEndianSwap( (unsigned short*)&var);
     }
     if ( gzwrite ( fd, (void *)(&var), sizeof(short) ) != sizeof(short) ) {
@@ -268,7 +240,7 @@ void sgReadFloat ( gzFile fd, const unsigned int n, float *var )
     if ( gzread ( fd, var, sizeof(float) * n ) != (int)(sizeof(float) * n) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         for ( unsigned int i = 0; i < n; ++i ) {
             sgEndianSwap( (unsigned int*)var++);
         }
@@ -278,7 +250,7 @@ void sgReadFloat ( gzFile fd, const unsigned int n, float *var )
 
 void sgWriteFloat ( gzFile fd, const unsigned int n, const float *var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         float *swab = new float[n];
         float *ptr = swab;
         memcpy( swab, var, sizeof(float) * n );
@@ -299,7 +271,7 @@ void sgReadDouble ( gzFile fd, const unsigned int n, double *var )
     if ( gzread ( fd, var, sizeof(double) * n ) != (int)(sizeof(double) * n) ) {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         for ( unsigned int i = 0; i < n; ++i ) {
             sgEndianSwap( (unsigned long long*)var++);
         }
@@ -309,7 +281,7 @@ void sgReadDouble ( gzFile fd, const unsigned int n, double *var )
 
 void sgWriteDouble ( gzFile fd, const unsigned int n, const double *var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         double *swab = new double[n];
         double *ptr = swab;
         memcpy( swab, var, sizeof(double) * n );
@@ -349,7 +321,7 @@ void sgReadUShort ( gzFile fd, const unsigned int n, unsigned short *var )
     {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         for ( unsigned int i = 0; i < n; ++i ) {
             sgEndianSwap( (unsigned short int*)var++);
         }
@@ -359,7 +331,7 @@ void sgReadUShort ( gzFile fd, const unsigned int n, unsigned short *var )
 
 void sgWriteUShort ( gzFile fd, const unsigned int n, const unsigned short *var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         unsigned short *swab = new unsigned short[n];
         unsigned short *ptr = swab;
         memcpy( swab, var, sizeof(unsigned short) * n );
@@ -384,7 +356,7 @@ void sgReadShort ( gzFile fd, const unsigned int n, short *var )
     {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         for ( unsigned int i = 0; i < n; ++i ) {
             sgEndianSwap( (unsigned short int*)var++);
         }
@@ -394,7 +366,7 @@ void sgReadShort ( gzFile fd, const unsigned int n, short *var )
 
 void sgWriteShort ( gzFile fd, const unsigned int n, const short *var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         short *swab = new short[n];
         short *ptr = swab;
         memcpy( swab, var, sizeof(short) * n );
@@ -418,7 +390,7 @@ void sgReadUInt ( gzFile fd, const unsigned int n, unsigned int *var )
     {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         for ( unsigned int i = 0; i < n; ++i ) {
             sgEndianSwap( (unsigned int*)var++);
         }
@@ -428,7 +400,7 @@ void sgReadUInt ( gzFile fd, const unsigned int n, unsigned int *var )
 
 void sgWriteUInt ( gzFile fd, const unsigned int n, const unsigned int *var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         unsigned int *swab = new unsigned int[n];
         unsigned int *ptr = swab;
         memcpy( swab, var, sizeof(unsigned int) * n );
@@ -453,7 +425,7 @@ void sgReadInt ( gzFile fd, const unsigned int n, int *var )
     {
         read_error = true ;
     }
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         for ( unsigned int i = 0; i < n; ++i ) {
             sgEndianSwap( (unsigned int*)var++);
         }
@@ -463,7 +435,7 @@ void sgReadInt ( gzFile fd, const unsigned int n, int *var )
 
 void sgWriteInt ( gzFile fd, const unsigned int n, const int *var )
 {
-    if ( sgIsBigEndian ) {
+    if ( sgIsBigEndian() ) {
         int *swab = new int[n];
         int *ptr = swab;
         memcpy( swab, var, sizeof(int) * n );

diff --git a/simgear/io/lowlevel.hxx b/simgear/io/lowlevel.hxx
index 82e37928f17f33669895953452b4f16a182ce843..dfc38162b0c99114f2e51599d89a23c5e9dd9bd1 100644 (file)
--- a/simgear/io/lowlevel.hxx
+++ b/simgear/io/lowlevel.hxx
@@ -40,7 +40,7 @@
 
 
 // Note that output is written in little endian form (and converted as
-// necessary)
+// necessary for big endian machines)
 
 void sgReadChar ( gzFile fd, char *var ) ;
 void sgWriteChar ( gzFile fd, const char var ) ;
@@ -119,5 +119,41 @@ void sgClearWriteError();
 int sgReadError();
 int sgWriteError();
 
+inline bool sgIsLittleEndian() {
+    static const int sgEndianTest = 1;
+    return (*((char *) &sgEndianTest ) != 0);
+}
+
+inline bool sgIsBigEndian() {
+    static const int sgEndianTest = 1;
+    return (*((char *) &sgEndianTest ) == 0);
+}
+
+inline void sgEndianSwap(unsigned short *x) {
+    *x =
+        (( *x >>  8 ) & 0x00FF ) | 
+        (( *x <<  8 ) & 0xFF00 ) ;
+}
+  
+inline void sgEndianSwap(unsigned int *x) {
+    *x =
+        (( *x >> 24 ) & 0x000000FF ) | 
+        (( *x >>  8 ) & 0x0000FF00 ) | 
+        (( *x <<  8 ) & 0x00FF0000 ) | 
+        (( *x << 24 ) & 0xFF000000 ) ;
+}
+  
+inline void sgEndianSwap(unsigned long long *x) {
+    *x =
+        (( *x >> 56 ) & 0x00000000000000FFULL ) | 
+        (( *x >> 40 ) & 0x000000000000FF00ULL ) | 
+        (( *x >> 24 ) & 0x0000000000FF0000ULL ) | 
+        (( *x >>  8 ) & 0x00000000FF000000ULL ) | 
+        (( *x <<  8 ) & 0x000000FF00000000ULL ) | 
+        (( *x << 24 ) & 0x0000FF0000000000ULL ) |
+        (( *x << 40 ) & 0x00FF000000000000ULL ) |
+        (( *x << 56 ) & 0xFF00000000000000ULL ) ;
+}
+  
 
 #endif // _SG_LOWLEVEL_HXX

diff --git a/simgear/io/lowtest.cxx b/simgear/io/lowtest.cxx
new file mode 100644 (file)
index 0000000..a808915
--- /dev/null
+++ b/simgear/io/lowtest.cxx
@@ -0,0 +1,44 @@
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <simgear/compiler.h>
+
+#include STL_IOSTREAM
+#include "lowlevel.hxx"
+
+static const int sgEndianTest = 1;
+#define sgIsLittleEndian (*((char *) &sgEndianTest ) != 0)
+#define sgIsBigEndian    (*((char *) &sgEndianTest ) == 0)
+
+
+int main() {
+    cout << "This machine is ";
+    if ( sgIsLittleEndian ) {
+        cout << "little ";
+    } else {
+        cout << "big ";
+    }
+    cout << "endian" << endl;
+
+    short s = 1111;
+    cout << "short s = " << s << endl;
+    sgEndianSwap((unsigned short *)&s);
+    cout << "short s = " << s << endl;
+    sgEndianSwap((unsigned short *)&s);
+    cout << "short s = " << s << endl;
+
+    int i = 1111111;
+    cout << "int i = " << i << endl;
+    sgEndianSwap((unsigned int *)&i);
+    cout << "int i = " << i << endl;
+    sgEndianSwap((unsigned int *)&i);
+    cout << "int i = " << i << endl;
+
+    double x = 1111111111;
+    cout << "double x = " << x << endl;
+    sgEndianSwap((unsigned long long *)&x);
+    cout << "double x = " << x << endl;
+    sgEndianSwap((unsigned long long *)&x);
+    cout << "double x = " << x << endl;
+}