Author: brane
Date: Sun Apr 28 07:14:14 2013
New Revision: 1476724
URL: http://svn.apache.org/r1476724
Log:
* subversion/libsvn_delta/compose_delta.c (copy_source_ops): Avoid a warning
about condition always being true by unconditionally issuing the second
half of an overlapping target copy.
Also make reading the code slightly easier by making fix_offset and fix_limit
local constants.
Modified:
subversion/trunk/subversion/libsvn_delta/compose_delta.c
Modified: subversion/trunk/subversion/libsvn_delta/compose_delta.c
URL:
http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_delta/compose_delta.c?rev=1476724&r1=1476723&r2=1476724&view=diff
==============================================================================
--- subversion/trunk/subversion/libsvn_delta/compose_delta.c (original)
+++ subversion/trunk/subversion/libsvn_delta/compose_delta.c Sun Apr 28
07:14:14 2013
@@ -648,15 +648,17 @@ copy_source_ops(apr_size_t offset, apr_s
{
const svn_txdelta_op_t *const op = &window->ops[op_ndx];
const apr_size_t *const off = &ndx->offs[op_ndx];
- apr_size_t fix_offset;
- apr_size_t fix_limit;
+ const apr_size_t fix_offset = (offset > off[0] ? offset - off[0] : 0);
+ const apr_size_t fix_limit = (off[1] > limit ? off[1] - limit : 0);
+ /* Ideally, we'd do this check before assigning fix_offset and
+ fix_limit; but then we couldn't make them const whilst still
+ adhering to C90 rules. Instead, we're going to assume that a
+ smart optimizing compiler will reorder this check before the
+ local variable initialization. */
if (off[0] >= limit)
break;
- fix_offset = (offset > off[0] ? offset - off[0] : 0);
- fix_limit = (off[1] > limit ? off[1] - limit : 0);
-
/* It would be extremely weird if the fixed-up op had zero length. */
assert(fix_offset + fix_limit < op->length);
@@ -701,23 +703,22 @@ copy_source_ops(apr_size_t offset, apr_s
apr_size_t tgt_off = target_offset;
assert(ptn_length > ptn_overlap);
- /* ### FIXME: ptn_overlap is unsigned, so the if() condition
- below is always true! Either it should be '> 0', or the
- code block should be unconditional. See also r842362. */
- if (ptn_overlap >= 0)
- {
- /* Issue second subrange in the pattern. */
- const apr_size_t length =
- MIN(op->length - fix_off - fix_limit,
- ptn_length - ptn_overlap);
- copy_source_ops(op->offset + ptn_overlap,
- op->offset + ptn_overlap + length,
- tgt_off,
- op_ndx,
- build_baton, window, ndx, pool);
- fix_off += length;
- tgt_off += length;
- }
+ /* Unconditionally issue the second subrange of the
+ pattern. This is always correct, since the outer
+ condition already verifies that there is an overlap
+ in the target copy. */
+ {
+ const apr_size_t length =
+ MIN(op->length - fix_off - fix_limit,
+ ptn_length - ptn_overlap);
+ copy_source_ops(op->offset + ptn_overlap,
+ op->offset + ptn_overlap + length,
+ tgt_off,
+ op_ndx,
+ build_baton, window, ndx, pool);
+ fix_off += length;
+ tgt_off += length;
+ }
assert(fix_off + fix_limit <= op->length);
if (ptn_overlap > 0
