+void *checked_calloc(unsigned long size)
+{
+ void *ptr;
+
+ ptr = calloc(1, size);
+
+ if (ptr == NULL)
+ Error(ERR_EXIT, "cannot allocate %d bytes -- out of memory", size);
+
+ return ptr;
+}
+
+short getFile16BitInteger(FILE *file, int byte_order)
+{
+ if (byte_order == BYTE_ORDER_BIG_ENDIAN)
+ return ((fgetc(file) << 8) |
+ (fgetc(file) << 0));
+ else /* BYTE_ORDER_LITTLE_ENDIAN */
+ return ((fgetc(file) << 0) |
+ (fgetc(file) << 8));
+}
+
+void putFile16BitInteger(FILE *file, short value, int byte_order)
+{
+ if (byte_order == BYTE_ORDER_BIG_ENDIAN)
+ {
+ fputc((value >> 8) & 0xff, file);
+ fputc((value >> 0) & 0xff, file);
+ }
+ else /* BYTE_ORDER_LITTLE_ENDIAN */
+ {
+ fputc((value >> 0) & 0xff, file);
+ fputc((value >> 8) & 0xff, file);
+ }
+}
+
+int getFile32BitInteger(FILE *file, int byte_order)
+{
+ if (byte_order == BYTE_ORDER_BIG_ENDIAN)
+ return ((fgetc(file) << 24) |
+ (fgetc(file) << 16) |
+ (fgetc(file) << 8) |
+ (fgetc(file) << 0));
+ else /* BYTE_ORDER_LITTLE_ENDIAN */
+ return ((fgetc(file) << 0) |
+ (fgetc(file) << 8) |
+ (fgetc(file) << 16) |
+ (fgetc(file) << 24));
+}
+
+void putFile32BitInteger(FILE *file, int value, int byte_order)
+{
+ if (byte_order == BYTE_ORDER_BIG_ENDIAN)
+ {
+ fputc((value >> 24) & 0xff, file);
+ fputc((value >> 16) & 0xff, file);
+ fputc((value >> 8) & 0xff, file);
+ fputc((value >> 0) & 0xff, file);
+ }
+ else /* BYTE_ORDER_LITTLE_ENDIAN */
+ {
+ fputc((value >> 0) & 0xff, file);
+ fputc((value >> 8) & 0xff, file);
+ fputc((value >> 16) & 0xff, file);
+ fputc((value >> 24) & 0xff, file);
+ }
+}
+
+void getFileChunk(FILE *file, char *chunk_buffer, int *chunk_length,
+ int byte_order)
+{
+ const int chunk_identifier_length = 4;
+
+ /* read chunk identifier */
+ fgets(chunk_buffer, chunk_identifier_length + 1, file);
+
+ /* read chunk length */
+ *chunk_length = getFile32BitInteger(file, byte_order);
+}
+
+void putFileChunk(FILE *file, char *chunk_name, int chunk_length,
+ int byte_order)
+{
+ /* write chunk identifier */
+ fputs(chunk_name, file);
+
+ /* write chunk length */
+ putFile32BitInteger(file, chunk_length, byte_order);
+}
+