[svn-r4643] Purpose:

    Code cleanup
Description:
    Windows is generating hundreds of warnings from some of the practices in
    the library.  Mostly, they are because size_t is 32-bit and hsize_t is
    64-bit on Windows and we were carelessly casting the larger values down to
    the smaller ones without checking for overflow.

    Also, some other small code cleanups,etc.

Solution:
    Re-worked some algorithms to eliminate the casts and also added more
    overflow checking for assignments and function parameters which needed
    casts.

    Kent did most of the work, I just went over his changes and fit them into
    the the library code a bit better.

Platforms tested:
    FreeBSD 4.4 (hawkwind)

1 files changed, 15 insertions, 6 deletions

diff --git a/src/H5FD.c b/src/H5FD.c
index c2f893f..9262323 100644
--- a/src/H5FD.c
+++ b/src/H5FD.c
@@ -2035,7 +2035,10 @@ H5FD_read(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, size_t siz
 
         unsigned char *read_buf=(unsigned char *)buf; /* Pointer to the buffer being read in */
         size_t amount_read;         /* Amount to read at a time */
-        haddr_t read_off;           /* Offset to read from */
+#ifndef NDEBUG
+        hsize_t tempamount_read;         /* Amount to read at a time */
+#endif /* NDEBUG */
+        hsize_t read_off;           /* Offset to read from */
 
         /* Double check that we aren't reading raw data */
         assert(type!=H5FD_MEM_DRAW);
@@ -2043,7 +2046,7 @@ H5FD_read(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, size_t siz
         /* Read the part before the metadata accumulator */
         if(addr<file->accum_loc) {
             /* Set the amount to read */
-            amount_read=file->accum_loc-addr;
+            H5_ASSIGN_OVERFLOW(amount_read,file->accum_loc-addr,hsize_t,size_t);
 
             /* Dispatch to driver */
             if ((file->cls->read)(file, type, dxpl_id, addr, amount_read, read_buf)<0)
@@ -2061,7 +2064,13 @@ H5FD_read(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, size_t siz
             read_off=addr-file->accum_loc;
 
             /* Set the amount to "read" */
-            amount_read=MIN((file->accum_size-read_off),size);
+#ifndef NDEBUG
+            tempamount_read = file->accum_size-read_off;
+            H5_CHECK_OVERFLOW(tempamount_read,hsize_t,size_t);
+            amount_read = MIN(size, (size_t)tempamount_read);
+#else /* NDEBUG */
+            amount_read = MIN(size, (size_t)tempamount_read);
+#endif /* NDEBUG */
 
             /* Copy the data out of the buffer */
             HDmemcpy(read_buf,file->meta_accum+read_off,amount_read);
@@ -2249,7 +2258,7 @@ H5FD_write(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, size_t si
                 /* Check if the new metadata overlaps the beginning of the current accumulator */
                 else if(addr<file->accum_loc && (addr+size)<=(file->accum_loc+file->accum_size)) {
                     /* Calculate the new accumulator size, based on the amount of overlap */
-                    new_size=(file->accum_loc-addr)+file->accum_size;
+                    H5_ASSIGN_OVERFLOW(new_size,(file->accum_loc-addr)+file->accum_size,hsize_t,size_t);
 
                     /* Check if we need more buffer space */
                     if(new_size>file->accum_buf_size) {
@@ -2262,7 +2271,7 @@ H5FD_write(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, size_t si
                     } /* end if */
 
                     /* Calculate the proper offset of the existing metadata */
-                    old_offset=(addr+size)-file->accum_loc;
+                    H5_ASSIGN_OVERFLOW(old_offset,(addr+size)-file->accum_loc,hsize_t,size_t);
 
                     /* Move the existing metadata to the proper location */
                     HDmemmove(file->meta_accum+size,file->meta_accum+old_offset,(file->accum_size-old_offset));
@@ -2280,7 +2289,7 @@ H5FD_write(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, size_t si
                 /* Check if the new metadata overlaps the end of the current accumulator */
                 else if(addr>=file->accum_loc && (addr+size)>(file->accum_loc+file->accum_size)) {
                     /* Calculate the new accumulator size, based on the amount of overlap */
-                    new_size=(addr-file->accum_loc)+size;
+                    H5_ASSIGN_OVERFLOW(new_size,(addr-file->accum_loc)+size,hsize_t,size_t);
 
                     /* Check if we need more buffer space */
                     if(new_size>file->accum_buf_size) {