Add hooking functionality

This allows us to hook chosen functions and do interesting things there (in
particular: reentrancy checking).

test/include/test/jemalloc_test.h.in

@@ -45,6 +45,7 @@ extern "C" {
 #  define JEMALLOC_MANGLE
 #  include "jemalloc/internal/jemalloc_internal.h"
 
+
 /******************************************************************************/
 /*
  * For integration tests, expose the public jemalloc interfaces, but only
@@ -68,6 +69,7 @@ static const bool config_debug =
 
 #  define JEMALLOC_N(n) @private_namespace@##n
 #  include "jemalloc/internal/private_namespace.h"
+#  include "jemalloc/internal/hooks.h"
 
 /* Hermetic headers. */
 #  include "jemalloc/internal/assert.h"

test/include/test/test.h

@@ -310,6 +310,9 @@ label_test_end:								\
 #define test(...)							\
 	p_test(__VA_ARGS__, NULL)
 
+#define test_no_reentrancy(...)							\
+	p_test_no_reentrancy(__VA_ARGS__, NULL)
+
 #define test_no_malloc_init(...)					\
 	p_test_no_malloc_init(__VA_ARGS__, NULL)
 
@@ -321,11 +324,14 @@ label_test_end:								\
 	}								\
 } while (0)
 
+bool test_is_reentrant();
+
 void	test_skip(const char *format, ...) JEMALLOC_FORMAT_PRINTF(1, 2);
 void	test_fail(const char *format, ...) JEMALLOC_FORMAT_PRINTF(1, 2);
 
 /* For private use by macros. */
 test_status_t	p_test(test_t *t, ...);
+test_status_t	p_test_no_reentrancy(test_t *t, ...);
 test_status_t	p_test_no_malloc_init(test_t *t, ...);
 void	p_test_init(const char *name);
 void	p_test_fini(void);