Hi Paul.
I think we can tighten the validation of svn_merge_range_t to exclude
change number "r0" (RANGE->start == -1) as in the following patch.
My reasoning is that a change numbered "r0" is not a valid concept in
any Subversion system because the state (tree-snapshot) numbered r0 is
by definition the beginning. (It also happens to be empty by
definition, but that's not so relevant.) We can say the same in a
different way: change "r0" would mean the change from "r(-1)" to "r0",
and "r(-1)" is not a valid concept.
Makes sense?
[[[
Tighten merge-range validation to not allow "change number r0" aka "revision
range -1:Y".
* subversion/libsvn_subr/mergeinfo.c
(IS_VALID_FORWARD_RANGE): New macro.
(get_type_of_intersection): Use IS_VALID_FORWARD_RANGE() for tighter
validation of arguments than before: it previously accepted "change 0".
(range_intersect, range_contains): Validate arguments. Add doc strings.
* subversion/tests/libsvn_subr/mergeinfo-test.c
(randomly_fill_rev_array, rev_array_to_rangelist): Expand doc strings.
(test_rangelist_remove_randomly, test_rangelist_intersect_randomly): Don't
ever include change number r0 in a merge range.
--This line, and those below, will be ignored--
Index: subversion/tests/libsvn_subr/mergeinfo-test.c
===================================================================
--- subversion/tests/libsvn_subr/mergeinfo-test.c (revision 922300)
+++ subversion/tests/libsvn_subr/mergeinfo-test.c (working copy)
@@ -877,24 +877,27 @@ test_remove_rangelist(apr_pool_t *pool)
#define RANDOM_REV_ARRAY_LENGTH 100
/* Random number seed. */
static apr_uint32_t random_rev_array_seed;
-/* Fill 3/4 of the array with 1s. */
+/* Set a random 3/4-ish of the elements of array REVS[RANDOM_REV_ARRAY_LENGTH]
+ * to TRUE and the rest to FALSE. */
static void
randomly_fill_rev_array(svn_boolean_t *revs)
{
int i;
for (i = 0; i < RANDOM_REV_ARRAY_LENGTH; i++)
{
apr_uint32_t next = svn_test_rand(&random_rev_array_seed);
revs[i] = (next < 0x40000000) ? 0 : 1;
}
}
+/* Set *RANGELIST to a rangelist representing the revisions that are marked
+ * with TRUE in the array REVS[RANDOM_REV_ARRAY_LENGTH]. */
static svn_error_t *
rev_array_to_rangelist(apr_array_header_t **rangelist,
svn_boolean_t *revs,
apr_pool_t *pool)
{
svn_stringbuf_t *buf = svn_stringbuf_create("/trunk: ", pool);
@@ -943,12 +946,15 @@ test_rangelist_remove_randomly(apr_pool_
int j;
svn_pool_clear(iterpool);
randomly_fill_rev_array(first_revs);
randomly_fill_rev_array(second_revs);
+ /* There is no change numbered "r0" */
+ first_revs[0] = FALSE;
+ second_revs[0] = FALSE;
for (j = 0; j < RANDOM_REV_ARRAY_LENGTH; j++)
expected_revs[j] = second_revs[j] && !first_revs[j];
SVN_ERR(rev_array_to_rangelist(&first_rangelist, first_revs, iterpool));
SVN_ERR(rev_array_to_rangelist(&second_rangelist, second_revs,
iterpool));
SVN_ERR(rev_array_to_rangelist(&expected_rangelist, expected_revs,
@@ -998,12 +1004,15 @@ test_rangelist_intersect_randomly(apr_po
int j;
svn_pool_clear(iterpool);
randomly_fill_rev_array(first_revs);
randomly_fill_rev_array(second_revs);
+ /* There is no change numbered "r0" */
+ first_revs[0] = FALSE;
+ second_revs[0] = FALSE;
for (j = 0; j < RANDOM_REV_ARRAY_LENGTH; j++)
expected_revs[j] = second_revs[j] && first_revs[j];
SVN_ERR(rev_array_to_rangelist(&first_rangelist, first_revs, iterpool));
SVN_ERR(rev_array_to_rangelist(&second_rangelist, second_revs,
iterpool));
SVN_ERR(rev_array_to_rangelist(&expected_rangelist, expected_revs,
Index: subversion/libsvn_subr/mergeinfo.c
===================================================================
--- subversion/libsvn_subr/mergeinfo.c (revision 922300)
+++ subversion/libsvn_subr/mergeinfo.c (working copy)
@@ -112,12 +112,22 @@ parse_pathname(const char **input,
*input = last_colon;
return SVN_NO_ERROR;
}
+/* Return TRUE iff (svn_merge_range_t *) RANGE describes a valid, forward
+ * revision range.
+ *
+ * Note: The smallest valid value of RANGE->start is 0 because it is an
+ * exclusive endpoint, being one less than the revision number of the first
+ * change described by the range, and the oldest possible change is "r1" as
+ * there cannot be a change "r0". */
+#define IS_VALID_FORWARD_RANGE(range) \
+ (SVN_IS_VALID_REVNUM((range)->start) && ((range)->start < (range)->end))
+
/* Ways in which two svn_merge_range_t can intersect or adjoin, if at all. */
typedef enum
{
/* Ranges don't intersect and don't adjoin. */
svn__no_intersection,
@@ -141,22 +151,14 @@ static svn_error_t *
get_type_of_intersection(const svn_merge_range_t *r1,
const svn_merge_range_t *r2,
intersection_type_t *intersection_type)
{
SVN_ERR_ASSERT(r1);
SVN_ERR_ASSERT(r2);
-
- /* Why not use SVN_IS_VALID_REVNUM here? Because revision 0
- is described START = -1, END = 0. See svn_merge_range_t. */
- SVN_ERR_ASSERT(r1->start >= -1);
- SVN_ERR_ASSERT(r2->start >= -1);
-
- SVN_ERR_ASSERT(SVN_IS_VALID_REVNUM(r1->end));
- SVN_ERR_ASSERT(SVN_IS_VALID_REVNUM(r2->end));
- SVN_ERR_ASSERT(r1->start < r1->end);
- SVN_ERR_ASSERT(r2->start < r2->end);
+ SVN_ERR_ASSERT(IS_VALID_FORWARD_RANGE(r1));
+ SVN_ERR_ASSERT(IS_VALID_FORWARD_RANGE(r2));
if (!(r1->start <= r2->end && r2->start <= r1->end))
*intersection_type = svn__no_intersection;
else if (r1->start == r2->start && r1->end == r2->end)
*intersection_type = svn__equal_intersection;
else if (r1->end == r2->start || r2->end == r1->start)
@@ -760,26 +762,37 @@ svn_rangelist_merge(apr_array_header_t *
}
*rangelist = output;
return SVN_NO_ERROR;
}
+/* Return TRUE iff the forward revision ranges FIRST and SECOND overlap and
+ * (if CONSIDER_INHERITANCE is TRUE) have the same inheritability. */
static svn_boolean_t
range_intersect(const svn_merge_range_t *first, const svn_merge_range_t
*second,
svn_boolean_t consider_inheritance)
{
+ SVN_ERR_ASSERT_NO_RETURN(IS_VALID_FORWARD_RANGE(first));
+ SVN_ERR_ASSERT_NO_RETURN(IS_VALID_FORWARD_RANGE(second));
+
return (first->start + 1 <= second->end)
&& (second->start + 1 <= first->end)
&& (!consider_inheritance
|| (!(first->inheritable) == !(second->inheritable)));
}
+/* Return TRUE iff the forward revision range FIRST wholly contains the
+ * forward revision range SECOND and (if CONSIDER_INHERITANCE is TRUE) has
+ * the same inheritability. */
static svn_boolean_t
range_contains(const svn_merge_range_t *first, const svn_merge_range_t *second,
svn_boolean_t consider_inheritance)
{
+ SVN_ERR_ASSERT_NO_RETURN(IS_VALID_FORWARD_RANGE(first));
+ SVN_ERR_ASSERT_NO_RETURN(IS_VALID_FORWARD_RANGE(second));
+
return (first->start <= second->start) && (second->end <= first->end)
&& (!consider_inheritance
|| (!(first->inheritable) == !(second->inheritable)));
}
/* Swap start and end fields of RANGE. */
]]]
- Julian
