Fix an integer overflow bug in {size2index,s2u}_compute().

This {bug,regression} was introduced by
155bfa7da18cab0d21d87aa2dce4554166836f5d (Normalize size classes.).

This resolves #241.

1 files changed, 89 insertions, 0 deletions

diff --git a/test/unit/size_classes.c b/test/unit/size_classes.c
new file mode 100644
index 0000000..d791834
--- /dev/null
+++ b/test/unit/size_classes.c
@@ -0,0 +1,89 @@
+#include "test/jemalloc_test.h"
+
+static size_t
+get_max_size_class(void)
+{
+	unsigned nhchunks;
+	size_t mib[4];
+	size_t sz, miblen, max_size_class;
+
+	sz = sizeof(unsigned);
+	assert_d_eq(mallctl("arenas.nhchunks", &nhchunks, &sz, NULL, 0), 0,
+	    "Unexpected mallctl() error");
+
+	miblen = sizeof(mib) / sizeof(size_t);
+	assert_d_eq(mallctlnametomib("arenas.hchunk.0.size", mib, &miblen), 0,
+	    "Unexpected mallctlnametomib() error");
+	mib[2] = nhchunks - 1;
+
+	sz = sizeof(size_t);
+	assert_d_eq(mallctlbymib(mib, miblen, &max_size_class, &sz, NULL, 0), 0,
+	    "Unexpected mallctlbymib() error");
+
+	return (max_size_class);
+}
+
+TEST_BEGIN(test_size_classes)
+{
+	size_t size_class, max_size_class;
+	index_t index, max_index;
+
+	max_size_class = get_max_size_class();
+	max_index = size2index(max_size_class);
+
+	for (index = 0, size_class = index2size(index); index < max_index ||
+	    size_class < max_size_class; index++, size_class =
+	    index2size(index)) {
+		assert_true(index < max_index,
+		    "Loop conditionals should be equivalent; index=%u, "
+		    "size_class=%zu (%#zx)", index, size_class, size_class);
+		assert_true(size_class < max_size_class,
+		    "Loop conditionals should be equivalent; index=%u, "
+		    "size_class=%zu (%#zx)", index, size_class, size_class);
+
+		assert_u_eq(index, size2index(size_class),
+		    "size2index() does not reverse index2size(): index=%u -->"
+		    " size_class=%zu --> index=%u --> size_class=%zu", index,
+		    size_class, size2index(size_class),
+		    index2size(size2index(size_class)));
+		assert_zu_eq(size_class, index2size(size2index(size_class)),
+		    "index2size() does not reverse size2index(): index=%u -->"
+		    " size_class=%zu --> index=%u --> size_class=%zu", index,
+		    size_class, size2index(size_class),
+		    index2size(size2index(size_class)));
+
+		assert_u_eq(index+1, size2index(size_class+1),
+		    "Next size_class does not round up properly");
+
+		assert_zu_eq(size_class, (index > 0) ?
+		    s2u(index2size(index-1)+1) : s2u(1),
+		    "s2u() does not round up to size class");
+		assert_zu_eq(size_class, s2u(size_class-1),
+		    "s2u() does not round up to size class");
+		assert_zu_eq(size_class, s2u(size_class),
+		    "s2u() does not compute same size class");
+		assert_zu_eq(s2u(size_class+1), index2size(index+1),
+		    "s2u() does not round up to next size class");
+	}
+
+	assert_u_eq(index, size2index(index2size(index)),
+	    "size2index() does not reverse index2size()");
+	assert_zu_eq(max_size_class, index2size(size2index(max_size_class)),
+	    "index2size() does not reverse size2index()");
+
+	assert_zu_eq(size_class, s2u(index2size(index-1)+1),
+	    "s2u() does not round up to size class");
+	assert_zu_eq(size_class, s2u(size_class-1),
+	    "s2u() does not round up to size class");
+	assert_zu_eq(size_class, s2u(size_class),
+	    "s2u() does not compute same size class");
+}
+TEST_END
+
+int
+main(void)
+{
+
+	return (test(
+	    test_size_classes));
+}