[svn-r306] Changes since 19980305

----------------------

./src/H5D.c
./test/external.c
        A contiguous dataset can now be stored in external files in
        such a way that the slowest varying dimension can be increased
        after the dataset is created and even written.  The user must
        have reserved enough space in the external file and the data
        space must allow an increase the the slowest varying dimension.
        See test_3() of ./test/external.c

./src/H5Oefl.c
./configure.in
./src/H5Fprivate.h
        Fixed an overflow bug with unlimited external storage.

./src/H5V.c
        Fixed a cast warning.

./test/dsets.c
        Make better use of automatic error reporting.

1 files changed, 11 insertions, 0 deletions

diff --git a/src/H5Fprivate.h b/src/H5Fprivate.h
index 497a9a0..77a299f 100644
--- a/src/H5Fprivate.h
+++ b/src/H5Fprivate.h
@@ -209,6 +209,17 @@
 #define NBYTEDECODE(s, d, n) {	 HDmemcpy(d,s,n); p+=n }
 
 /*
+ * Macros that check for overflows.  These are somewhat dangerous to fiddle
+ * with.
+ */
+#if (SIZEOF_SIZE_T >= SIZEOF_OFF_T)
+#   define H5F_OVERFLOW_SIZET2OFFT(X)					      \
+    ((size_t)(X)>=(size_t)((size_t)1<<(8*sizeof(off_t)-1)))
+#else
+#   define H5F_OVERFLOW_SIZET2OFFT(X) 0
+#endif
+
+/*
  * File-creation property list.
  */
 typedef struct H5F_create_t {