# HG changeset patch
# User Mike Becker <universe@uap-core.de>
# Date 1734905407 -3600
# Node ID 3df63e95921a4a27e6471572f7e55fb45caa4fd7
# Parent  415bf2ce6bab97e7430f5a3e6022f1d3d4af7d9d
make cx_strcast() also support cxstring

also makes the solution for issue #536 a lot nicer

diff -r 415bf2ce6bab -r 3df63e95921a CHANGELOG
--- a/CHANGELOG	Sun Dec 22 22:53:53 2024 +0100
+++ b/CHANGELOG	Sun Dec 22 23:10:07 2024 +0100
@@ -20,6 +20,7 @@
    to accept NULL as allocator argument (in which case a default allocator will be used)
  * changes the name of destroy functions that actually free the memory to better indicate their behavior
  * change cx_strcat variants to allow handling of ENOMEM
+ * change cx_strcast() to also accept cxstring (and doing nothing in that case)
  * change the behavior of cxBufferSeek() to allow offset zero for SEEK_END
  * moves cx_compare_func typedef to compare.h
  * moves cx_szmul() to common.h
@@ -30,7 +31,7 @@
  * removes CMake
  * removes GTest dependency
  * removes flags to disable SBO in tests
- * fixes cx_hash_key_cxstr() being a macro, evaluating the argument twice
+ * fixes cx_hash_key_cxstr() evaluating the argument twice
  * fixes wrong link from UCX 2 documentation to UCX 3 documentation
  * fixes critical bug that produced wrong results when comparing lists of different type but same size
 
diff -r 415bf2ce6bab -r 3df63e95921a src/Makefile
--- a/src/Makefile	Sun Dec 22 22:53:53 2024 +0100
+++ b/src/Makefile	Sun Dec 22 23:10:07 2024 +0100
@@ -85,7 +85,8 @@
 	@echo "Compiling $<"
 	$(CC) -o $@ $(CFLAGS)  -c $<
 
-$(build_dir)/hash_key$(OBJ_EXT): hash_key.c cx/hash_key.h cx/common.h
+$(build_dir)/hash_key$(OBJ_EXT): hash_key.c cx/hash_key.h cx/common.h \
+ cx/string.h cx/allocator.h
 	@echo "Compiling $<"
 	$(CC) -o $@ $(CFLAGS)  -c $<
 
diff -r 415bf2ce6bab -r 3df63e95921a src/cx/hash_key.h
--- a/src/cx/hash_key.h	Sun Dec 22 22:53:53 2024 +0100
+++ b/src/cx/hash_key.h	Sun Dec 22 23:10:07 2024 +0100
@@ -118,46 +118,27 @@
         size_t len
 );
 
-#ifdef __cplusplus
-} // extern "C"
-
-cx_attr_nodiscard
-static inline CxHashKey cx_hash_key_cxstr(cxstring str) {
-    return cx_hash_key(str.ptr, str.length);
-}
-
-cx_attr_nodiscard
-static inline CxHashKey cx_hash_key_cxstr(cxmutstr str) {
-    return cx_hash_key(str.ptr, str.length);
-}
-
-#else
 /**
  * Computes a hash key from a UCX string.
  *
  * @param str the string
  * @return the hash key
  */
-#define cx_hash_key_cxstr(str) _Generic((str), \
-    cxstring: cx_hash_key_cxstring, \
-    cxmutstr: cx_hash_key_cxmutstr) \
-    (str)
-
-/**
- * @copydoc cx_hash_key_cxstr()
- */
 cx_attr_nodiscard
-static inline CxHashKey cx_hash_key_cxstring(cxstring str) {
+static inline CxHashKey cx_hash_key_cxstr(cxstring str) {
     return cx_hash_key(str.ptr, str.length);
 }
 
 /**
- * @copydoc cx_hash_key_cxstr()
+ * Computes a hash key from a UCX string.
+ *
+ * @param str the string
+ * @return the hash key
  */
-cx_attr_nodiscard
-static inline CxHashKey cx_hash_key_cxmutstr(cxmutstr str) {
-    return cx_hash_key(str.ptr, str.length);
-}
+#define cx_hash_key_cxstr(str) cx_hash_key_cxstr(cx_strcast(str))
+
+#ifdef __cplusplus
+} // extern "C"
 #endif
 
 #endif // UCX_HASH_KEY_H
diff -r 415bf2ce6bab -r 3df63e95921a src/cx/string.h
--- a/src/cx/string.h	Sun Dec 22 22:53:53 2024 +0100
+++ b/src/cx/string.h	Sun Dec 22 23:10:07 2024 +0100
@@ -244,18 +244,56 @@
         size_t length
 );
 
+#ifdef __cplusplus
+} // extern "C"
+cx_attr_nodiscard
+static inline cxstring cx_strcast(cxmutstr str) {
+    return cx_strn(str.ptr, str.length);
+}
+cx_attr_nodiscard
+static inline cxstring cx_strcast(cxstring str) {
+    return str;
+}
+extern "C" {
+#else
+/**
+ * Internal function, do not use.
+ * @param str
+ * @return
+ * @see cx_strcast()
+ */
+cx_attr_nodiscard
+static inline cxstring cx_strcast_m(cxmutstr str) {
+    return (cxstring) {str.ptr, str.length};
+}
+/**
+ * Internal function, do not use.
+ * @param str
+ * @return
+ * @see cx_strcast()
+ */
+cx_attr_nodiscard
+static inline cxstring cx_strcast_c(cxstring str) {
+    return str;
+}
+
 /**
 * Casts a mutable string to an immutable string.
 *
-* \note This is not seriously a cast. Instead you get a copy
+* Does nothing for already immutable strings.
+*
+* \note This is not seriously a cast. Instead, you get a copy
 * of the struct with the desired pointer type. Both structs still
 * point to the same location, though!
 *
 * @param str the mutable string to cast
 * @return an immutable copy of the string pointer
 */
-cx_attr_nodiscard
-cxstring cx_strcast(cxmutstr str);
+#define cx_strcast(str) _Generic((str), \
+        cxmutstr: cx_strcast_m, \
+        cxstring: cx_strcast_c) \
+        (str)
+#endif
 
 /**
  * Passes the pointer in this string to \c free().
diff -r 415bf2ce6bab -r 3df63e95921a src/string.c
--- a/src/string.c	Sun Dec 22 22:53:53 2024 +0100
+++ b/src/string.c	Sun Dec 22 23:10:07 2024 +0100
@@ -63,10 +63,6 @@
     return (cxstring) {cstring, length};
 }
 
-cxstring cx_strcast(cxmutstr str) {
-    return (cxstring) {str.ptr, str.length};
-}
-
 void cx_strfree(cxmutstr *str) {
     if (str == NULL) return;
     free(str->ptr);
diff -r 415bf2ce6bab -r 3df63e95921a tests/Makefile
--- a/tests/Makefile	Sun Dec 22 22:53:53 2024 +0100
+++ b/tests/Makefile	Sun Dec 22 23:10:07 2024 +0100
@@ -70,7 +70,7 @@
 
 $(TEST_DIR)/test_hash_key$(OBJ_EXT): test_hash_key.c ../src/cx/test.h \
  ../src/cx/common.h ../src/cx/hash_key.h ../src/cx/string.h \
- ../src/cx/allocator.h
+ ../src/cx/allocator.h ../src/cx/string.h
 	@echo "Compiling $<"
 	$(CC) -o $@ $(CFLAGS) -I../src -c $<