Move endian determination to be compile-time constant determined by configure

and conveniently defaulting to LE for our favorite configure-less environment.

diff --git a/config.h.in b/config.h.in
index 1bd4136c8bd6b62045239f878d6ec1e803682b9f..0e668d4f0ad2eb334b85587fcc92a1163af5ef97 100644 (file)
--- a/config.h.in
+++ b/config.h.in
@@ -51,5 +51,9 @@
 /* 1 to enable shapefile support */
 #undef SHAPELIB_ENABLED
 
+/* Define to 1 if your processor stores words with the most significant byte
+   first (like Motorola and SPARC, unlike Intel and VAX). */
+#undef WORDS_BIGENDIAN
+
 /* 1 to inhibit our use of zlib. */
 #undef ZLIB_INHIBITED

diff --git a/configure b/configure
index 04f8788d1a666ef3e50609799d31bf1a0ffcac7d..5b2798e1e6eada2cdfece34a719fc528be9f23c9 100755 (executable)
--- a/configure
+++ b/configure
@@ -2448,8 +2448,238 @@ fi
 
 
 
-# Checks for libraries.
+echo "$as_me:$LINENO: checking whether byte ordering is bigendian" >&5
+echo $ECHO_N "checking whether byte ordering is bigendian... $ECHO_C" >&6
+if test "${ac_cv_c_bigendian+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  # See if sys/param.h defines the BYTE_ORDER macro.
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+#include <sys/types.h>
+#include <sys/param.h>
+
+int
+main ()
+{
+#if !BYTE_ORDER || !BIG_ENDIAN || !LITTLE_ENDIAN
+ bogus endian macros
+#endif
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+  (eval $ac_compile) 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+        { ac_try='test -z "$ac_c_werror_flag"
+                        || test ! -s conftest.err'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } &&
+        { ac_try='test -s conftest.$ac_objext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  # It does; now see whether it defined to BIG_ENDIAN or not.
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+#include <sys/types.h>
+#include <sys/param.h>
+
+int
+main ()
+{
+#if BYTE_ORDER != BIG_ENDIAN
+ not big endian
+#endif
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+  (eval $ac_compile) 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+        { ac_try='test -z "$ac_c_werror_flag"
+                        || test ! -s conftest.err'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } &&
+        { ac_try='test -s conftest.$ac_objext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  ac_cv_c_bigendian=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ac_cv_c_bigendian=no
+fi
+rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
 
+# It does not; compile a test program.
+if test "$cross_compiling" = yes; then
+  # try to guess the endianness by grepping values into an object file
+  ac_cv_c_bigendian=unknown
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+short ascii_mm[] = { 0x4249, 0x4765, 0x6E44, 0x6961, 0x6E53, 0x7953, 0 };
+short ascii_ii[] = { 0x694C, 0x5454, 0x656C, 0x6E45, 0x6944, 0x6E61, 0 };
+void _ascii () { char *s = (char *) ascii_mm; s = (char *) ascii_ii; }
+short ebcdic_ii[] = { 0x89D3, 0xE3E3, 0x8593, 0x95C5, 0x89C4, 0x9581, 0 };
+short ebcdic_mm[] = { 0xC2C9, 0xC785, 0x95C4, 0x8981, 0x95E2, 0xA8E2, 0 };
+void _ebcdic () { char *s = (char *) ebcdic_mm; s = (char *) ebcdic_ii; }
+int
+main ()
+{
+ _ascii (); _ebcdic ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+  (eval $ac_compile) 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+        { ac_try='test -z "$ac_c_werror_flag"
+                        || test ! -s conftest.err'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } &&
+        { ac_try='test -s conftest.$ac_objext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  if grep BIGenDianSyS conftest.$ac_objext >/dev/null ; then
+  ac_cv_c_bigendian=yes
+fi
+if grep LiTTleEnDian conftest.$ac_objext >/dev/null ; then
+  if test "$ac_cv_c_bigendian" = unknown; then
+    ac_cv_c_bigendian=no
+  else
+    # finding both strings is unlikely to happen, but who knows?
+    ac_cv_c_bigendian=unknown
+  fi
+fi
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+fi
+rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
+else
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+int
+main ()
+{
+  /* Are we little or big endian?  From Harbison&Steele.  */
+  union
+  {
+    long l;
+    char c[sizeof (long)];
+  } u;
+  u.l = 1;
+  exit (u.c[sizeof (long) - 1] == 1);
+}
+_ACEOF
+rm -f conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
+  (eval $ac_link) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  ac_cv_c_bigendian=no
+else
+  echo "$as_me: program exited with status $ac_status" >&5
+echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+( exit $ac_status )
+ac_cv_c_bigendian=yes
+fi
+rm -f core *.core gmon.out bb.out conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
+fi
+fi
+rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+echo "$as_me:$LINENO: result: $ac_cv_c_bigendian" >&5
+echo "${ECHO_T}$ac_cv_c_bigendian" >&6
+case $ac_cv_c_bigendian in
+  yes)
+
+cat >>confdefs.h <<\_ACEOF
+#define WORDS_BIGENDIAN 1
+_ACEOF
+ ;;
+  no)
+     ;;
+  *)
+    { { echo "$as_me:$LINENO: error: unknown endianness
+presetting ac_cv_c_bigendian=no (or yes) will help" >&5
+echo "$as_me: error: unknown endianness
+presetting ac_cv_c_bigendian=no (or yes) will help" >&2;}
+   { (exit 1); exit 1; }; } ;;
+esac
+
+
+# Checks for libraries.
 
 echo "$as_me:$LINENO: checking for cos in -lm" >&5
 echo $ECHO_N "checking for cos in -lm... $ECHO_C" >&6

diff --git a/configure.in b/configure.in
index baf3d0011f79194021510a46d0a58d61f3017638..3e58529c5f986a02af5745f972765d1e9af3e841 100644 (file)
--- a/configure.in
+++ b/configure.in
@@ -30,6 +30,7 @@ AC_PROG_INSTALL
 AC_PROG_MAKE_SET
 AC_EXEEXT
 AC_SUBST(AC_EXEEXT)
+AC_C_BIGENDIAN
 
 # Checks for libraries.
 AC_CHECK_LIB([m], [cos])

diff --git a/util.c b/util.c
index 0a0356d7c6d41ce98e3d9445cbe30e5f67051a79..d2e48bd4a9884296867396555b4cac1e5dfe8ef8 100644 (file)
--- a/util.c
+++ b/util.c
@@ -27,8 +27,11 @@
 #include <stdarg.h>
 #include <time.h>
 
-static int i_am_little_endian = -1;
-static int doswap(void);
+#if defined WORDS_BIGENDIAN
+# define i_am_little_endian 0
+#else
+# define i_am_little_endian 1
+#endif
 
 #ifdef DEBUG_MEM
 #define DEBUG_FILENAME "/tmp/gpsbabel.debug"
@@ -596,8 +599,6 @@ le_read64(void *dest, const void *src)
        char *cdest = dest;
        const char *csrc = src;
 
-       doswap(); /* make sure i_am_little_endian is initialized */
-
        if (i_am_little_endian) {
                memcpy(dest, src, 8);
        } else {
@@ -795,23 +796,6 @@ get_cache_icon(const waypoint *waypointp)
        return NULL;
 }
 
-static int doswap()
-{
-  if (i_am_little_endian < 0)
-  {
-       /*      On Intel, Vax and MIPs little endian, -1.0 maps to the bytes
-               0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf0, 0x3f and on Motorola,
-               SPARC, ARM, and PowerPC, it maps to
-               0x3f, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00.
-       */
-       double d = 1.0;
-       char c[8];
-       memcpy(c, &d, 8);
-       i_am_little_endian = (c[0] == 0);
-  }
-  return i_am_little_endian;
-}
-
 double
 endian_read_double(void* ptr, int read_le)
 {
@@ -819,7 +803,7 @@ endian_read_double(void* ptr, int read_le)
   char r[8];
   void *p;
   int i;
-  doswap(); /* make sure i_am_little_endian is initialized */
+  
   if ( i_am_little_endian == read_le ) {
          p = ptr;
   }
@@ -842,7 +826,6 @@ endian_write_double(void* ptr, double d, int write_le)
   int i;
   char *optr = ptr;
 
-  doswap(); /* make sure i_am_little_endian is initialized */
   if ( i_am_little_endian == write_le ) {
          memcpy( ptr, &d, 8);
   }