Add to_lower and to_upper functions

src/primitives/strings/str8/str8.c

@@ -4,6 +4,7 @@
 #include "../../../common/aliases/aliases.h"
 #include "../../../common/assert/assert.h"
 #include "../../mem_allocator/mem_allocator.h"
+#include <ctype.h>
 #include <stdarg.h>
 #include <stddef.h>
 #include <stdio.h>
@@ -240,6 +241,26 @@ void wapp_str8_format(Str8 *dst, const char *format, ...) {
   va_end(args2);
 }
 
+void wapp_str8_to_lower(Str8 *dst, Str8RO *src) {
+  wapp_debug_assert(src != NULL && dst != NULL, "`dst` and `src` should not be NULL");
+  wapp_debug_assert(dst->capacity >= src->capacity, "`dst` does not have enough capacity");
+
+  dst->size = src->size;
+  for (u64 i = 0; i < src->size; ++i) {
+    wapp_str8_set(dst, i, tolower(wapp_str8_get(src, i)));
+  }
+}
+
+void wapp_str8_to_upper(Str8 *dst, Str8RO *src) {
+  wapp_debug_assert(src != NULL && dst != NULL, "`dst` and `src` should not be NULL");
+  wapp_debug_assert(dst->capacity >= src->capacity, "`dst` does not have enough capacity");
+
+  dst->size = src->size;
+  for (u64 i = 0; i < src->size; ++i) {
+    wapp_str8_set(dst, i, toupper(wapp_str8_get(src, i)));
+  }
+}
+
 i64 wapp_str8_find(Str8RO *str, Str8RO substr) {
   if (!str || substr.size > str->size) {
     return -1;

src/primitives/strings/str8/str8.h

@@ -97,6 +97,8 @@ void wapp_str8_copy_cstr_capped(Str8 *dst, const char *src);
 void wapp_str8_copy_str8_capped(Str8 *dst, Str8RO *src);
 void wapp_str8_copy_to_cstr(char *dst, Str8RO *src, u64 dst_capacity);
 void wapp_str8_format(Str8 *dst, const char *format, ...);
+void wapp_str8_to_lower(Str8 *dst, Str8RO *src);
+void wapp_str8_to_upper(Str8 *dst, Str8RO *src);
 
 /**
  * Str8 find functions