This adds macros to implement (and/or declare) type-safe wrapper functions

[oweals/openssl.git] / crypto / lhash / lhash.h

diff --git a/crypto/lhash/lhash.h b/crypto/lhash/lhash.h
index 0c1e2d2338db20fd3af66d4e709243b00e92fd66..a6048a4b7d2a73bb2c18b46368e56f57d8947e5a 100644 (file)
--- a/crypto/lhash/lhash.h
+++ b/crypto/lhash/lhash.h
@@ -77,17 +77,62 @@ extern "C" {
 
 typedef struct lhash_node_st
        {
-       void *data;
+       const void *data;
        struct lhash_node_st *next;
 #ifndef NO_HASH_COMP
        unsigned long hash;
 #endif
        } LHASH_NODE;
 
-typedef int (*LHASH_COMP_FN_TYPE)(void *, void *);
-typedef unsigned long (*LHASH_HASH_FN_TYPE)(void *);
-typedef void (*LHASH_DOALL_FN_TYPE)(void *);
-typedef void (*LHASH_DOALL_ARG_FN_TYPE)(void *, void *);
+typedef int (*LHASH_COMP_FN_TYPE)(const void *, const void *);
+typedef unsigned long (*LHASH_HASH_FN_TYPE)(const void *);
+typedef void (*LHASH_DOALL_FN_TYPE)(const void *);
+typedef void (*LHASH_DOALL_ARG_FN_TYPE)(const void *, const void *);
+
+/* Macros for declaring and implementing type-safe wrappers for LHASH callbacks.
+ * This way, callbacks can be provided to LHASH structures without function
+ * pointer casting and the macro-defined callbacks provide per-variable casting
+ * before deferring to the underlying type-specific callbacks. NB: It is
+ * possible to place a "static" in front of both the DECLARE and IMPLEMENT
+ * macros if the functions are strictly internal. */
+
+/* First: "hash" functions */
+#define DECLARE_LHASH_HASH_FN(f_name,o_type) \
+       unsigned long f_name##_LHASH_HASH(const void *);
+#define IMPLEMENT_LHASH_HASH_FN(f_name,o_type) \
+       unsigned long f_name##_LHASH_HASH(const void *arg) { \
+               o_type a = (o_type)arg; \
+               return f_name(a); }
+#define LHASH_HASH_FN(f_name) f_name##_LHASH_HASH
+
+/* Second: "compare" functions */
+#define DECLARE_LHASH_COMP_FN(f_name,o_type) \
+       int f_name##_LHASH_COMP(const void *, const void *);
+#define IMPLEMENT_LHASH_COMP_FN(f_name,o_type) \
+       int f_name##_LHASH_COMP(const void *arg1, const void *arg2) { \
+               o_type a = (o_type)arg1; \
+               o_type b = (o_type)arg2; \
+               return f_name(a,b); }
+#define LHASH_COMP_FN(f_name) f_name##_LHASH_COMP
+
+/* Third: "doall" functions */
+#define DECLARE_LHASH_DOALL_FN(f_name,o_type) \
+       void f_name##_LHASH_DOALL(const void *);
+#define IMPLEMENT_LHASH_DOALL_FN(f_name,o_type) \
+       void f_name##_LHASH_DOALL(const void *arg) { \
+               o_type a = (o_type)arg; \
+               return f_name(a); }
+#define LHASH_DOALL_FN(f_name) f_name##_LHASH_DOALL
+
+/* Fourth: "doall_arg" functions */
+#define DECLARE_LHASH_DOALL_ARG_FN(f_name,o_type,a_type) \
+       void f_name##_LHASH_DOALL_ARG(const void *, const void *);
+#define IMPLEMENT_LHASH_DOALL_ARG_FN(f_name,o_type,a_type) \
+       void f_name##_LHASH_DOALL_ARG(const void *arg1, const void *arg2) { \
+               o_type a = (o_type)arg1; \
+               a_type b = (a_type)arg2; \
+               return f_name(a,b); }
+#define LHASH_DOALL_ARG_FN(f_name) f_name##_LHASH_DOALL_ARG
 
 typedef struct lhash_st
        {
@@ -127,11 +172,11 @@ typedef struct lhash_st
 
 LHASH *lh_new(LHASH_HASH_FN_TYPE h, LHASH_COMP_FN_TYPE c);
 void lh_free(LHASH *lh);
-void *lh_insert(LHASH *lh, void *data);
-void *lh_delete(LHASH *lh, void *data);
-void *lh_retrieve(LHASH *lh, void *data);
+void *lh_insert(LHASH *lh, const void *data);
+void *lh_delete(LHASH *lh, const void *data);
+void *lh_retrieve(LHASH *lh, const void *data);
 void lh_doall(LHASH *lh, LHASH_DOALL_FN_TYPE func);
-void lh_doall_arg(LHASH *lh, LHASH_DOALL_ARG_FN_TYPE func, void *arg);
+void lh_doall_arg(LHASH *lh, LHASH_DOALL_ARG_FN_TYPE func, const void *arg);
 unsigned long lh_strhash(const char *c);
 unsigned long lh_num_items(const LHASH *lh);