feature: add string duplication functions with error handling

Source/DrangPlatform/Include/drang/strings.h

@@ -0,0 +1,54 @@
+#pragma once
+
+#include "alloc.h"
+#include "platform.h"
+#include <stddef.h>
+
+DRANG_BEGIN_DECLS
+
+/**
+ * @brief Duplicates a null-terminated string.
+ * @param[in] str The null-terminated string to duplicate.
+ * @return Pointer to a newly allocated copy of the string, or NULL if allocation fails.
+ * @remarks The returned string must be freed using drang_free() when no longer needed.
+ *          The input string must be null-terminated. If str is NULL, the behavior is undefined.
+ */
+DRANG_PLATFORM_API char *drang_strdup(const char *str);
+
+/**
+ * @brief Duplicates at most n characters of a string.
+ * @param[in] str The string to duplicate (may or may not be null-terminated).
+ * @param[in] n Maximum number of characters to copy.
+ * @return Pointer to a newly allocated copy of the string, or NULL if allocation fails.
+ * @remarks The returned string is always null-terminated and must be freed using drang_free().
+ *          If str contains fewer than n characters, only the available characters are copied.
+ *          If str is NULL, the behavior is undefined.
+ */
+DRANG_PLATFORM_API char *drang_strndup(const char *str, size_t n);
+
+/**
+ * @brief Duplicates a string with automatic error handling.
+ * @param _Str_ The null-terminated string to duplicate.
+ * @return Pointer to a newly allocated copy of the string.
+ * @details This macro calls drang_strdup() and automatically triggers DRANG error handling
+ *          with DRANG_ENOMEM if allocation fails. The operation will jump to the cleanup
+ *          section if used within a DRANG_BEGIN_TRY()...DRANG_END_TRY() block.
+ * @remarks The returned string must be freed using drang_free() when no longer needed.
+ *          This macro should only be used within a DRANG error handling context.
+ */
+#define DRANG_TRY_STRDUP(_Str_) (char*)(DRANG_ALLOC_TRY_IMPL(drang_strdup((_Str_))))
+
+/**
+ * @brief Duplicates at most n characters of a string with automatic error handling.
+ * @param _Str_ The string to duplicate (may or may not be null-terminated).
+ * @param _N_ Maximum number of characters to copy.
+ * @return Pointer to a newly allocated copy of the string.
+ * @details This macro calls drang_strndup() and automatically triggers DRANG error handling
+ *          with DRANG_ENOMEM if allocation fails. The operation will jump to the cleanup
+ *          section if used within a DRANG_BEGIN_TRY()...DRANG_END_TRY() block.
+ * @remarks The returned string is always null-terminated and must be freed using drang_free().
+ *          This macro should only be used within a DRANG error handling context.
+ */
+#define DRANG_TRY_STRNDUP(_Str_, _N_) (char*)(DRANG_ALLOC_TRY_IMPL(drang_strndup((_Str_), (_N_))))
+
+DRANG_END_DECLS

Source/DrangPlatform/Source/strings.c

@@ -0,0 +1,25 @@
+#include <drang/strings.h>
+#include <string.h>
+
+char *drang_strdup(const char *str)
+{
+    if (!str) return NULL;
+    const size_t len = strlen(str);
+    char *dup = DRANG_ALLOC_T_N(char, len + 1);
+    if (dup) {
+        memcpy(dup, str, len);
+        dup[len] = '\0';
+    }
+    return dup;
+}
+char *drang_strndup(const char *str, size_t n)
+{
+    if (!str) return NULL;
+    const size_t len = strnlen(str, n);
+    char *dup = DRANG_ALLOC_T_N(char, len + 1);
+    if (dup) {
+        memcpy(dup, str, len);
+        dup[len] = '\0';
+    }
+    return dup;
+}