make string thread-safe

string/mystring.h

@@ -1,25 +1,27 @@
 #ifndef MYCLIB_STRING_H
 #define MYCLIB_STRING_H
 
+#include <pthread.h>
 #include <stddef.h>
 
 /**
- * @brief String structure
+ * @brief Thread-safe dynamic string structure
  */
 typedef struct mcl_string_t {
-	size_t size;	 /**< Length of the string (excluding null terminator) */
-	size_t capacity; /**< Total allocated capacity */
-	char *data;		 /**< Pointer to the string data */
+	size_t size;		  /**< Current length of the string (excluding null terminator) */
+	size_t capacity;	  /**< Allocated capacity */
+	char *data;			  /**< Pointer to string data */
+	pthread_mutex_t lock; /**< Mutex for thread safety */
 } mcl_string;
 
 /**
- * @brief Create a new string
+ * @brief Create a new string initialized with given text
  *
- * @param text The text to initialize from
- * @param initial_capacity The initial capacity, pass -1 to retrieve it from the text
- * @return Pointer to the new string, or NULL on failure
+ * @param text Initial text (cannot be NULL)
+ * @param initial_capacity Initial buffer capacity; pass -1 to auto-calculate
+ * @return Pointer to new string, or NULL on failure
  *
- * @note The caller is responsible for freeing the returned string with mcl_string_free() and to pass the right inital_capacity
+ * @note Caller must free the string with mcl_string_free()
  */
 mcl_string *mcl_string_new(const char *text, long initial_capacity);
 
@@ -27,47 +29,45 @@ mcl_string *mcl_string_new(const char *text, long initial_capacity);
  * @brief Append text to an existing string
  *
  * @param string The string to append to
- * @param text The string to append (can be empty)
+ * @param text Text to append (can be empty)
  * @return 0 on success, -1 on failure
  *
- * @note If it fails, the original string remains unchanged
+ * @note Original string remains unchanged if append fails
  */
 int mcl_string_append(mcl_string *string, const char *text);
 
 /**
- * @brief Free a string
+ * @brief Free a string and its resources
  *
- * @param string The string to free
- *
- * @note This function is safe to call with NULL pointers
+ * @param string String to free (NULL is safe)
  */
 void mcl_string_free(mcl_string *string);
 
 /**
  * @brief Get the current length of the string
  *
- * @param string The string to query
- * @return The length of the string, or 0 if string is NULL
+ * @param string String to query
+ * @return Length of string, or 0 if NULL
  */
-size_t mcl_string_length(const mcl_string *string);
+size_t mcl_string_length(mcl_string *string);
 
 /**
- * @brief Get the current capacity of the string
+ * @brief Get the current capacity of the string buffer
  *
- * @param string The string to query
- * @return The capacity of the string buffer, or 0 if string is NULL
+ * @param string String to query
+ * @return Capacity, or 0 if NULL
  */
-size_t mcl_string_capacity(const mcl_string *string);
+size_t mcl_string_capacity(mcl_string *string);
 
 /**
- * @brief Get a read-only string representation
+ * @brief Get a read-only C-string pointer
  *
- * @param string The string to access
- * @return Pointer to null-terminated string data, or empty string "" if string is NULL
+ * @param string String to access
+ * @return Null-terminated string pointer, or "" if NULL
  *
- * @warning The returned pointer should not be modified directly and may become
- *          invalid after any modification operation on the string
+ * @warning Do not modify returned pointer.
+ *          Pointer may become invalid after string modifications.
  */
-const char *mcl_string_cstr(const mcl_string *string);
+const char *mcl_string_cstr(mcl_string *string);
 
 #endif /* MYCLIB_STRING_H */