better engine architecture with more simplicity

engine/slc.h

@@ -10,7 +10,7 @@ enum SLC_WORDTYP {
 	/** "Threaded code" (utf16-like word offsets) and encoded parentheses IN-PLACE inlined where text was before */
 	SLC_WORDTYP_THREADED_INLINE = 2,
 	/** "Threaded code" that did not fit in-place and is thus stored in session storage, word offset tells where */
-	SLC_WORDTYP_THREADED_SESSION = 2
+	SLC_WORDTYP_THREADED_SESSION = 3
 };
 typedef enum SLC_WORDTYP SLC_WORDTYP;
 
@@ -83,7 +83,14 @@ enum SLC_SYM_OP { SLC_SYM_SET, SLC_SYM_GET, SLC_SYM_ERASE };
 typedef enum SLC_SYM_OP SLC_SYM_OP;
 enum SLC_STACK_OP { SLC_STACK_PUSH, SLC_STACK_POP, SLC_STACK_AT, SLC_STACK_COUNT, SLC_STACK_ERASE };
 typedef enum SLC_STACK_OP SLC_STACK_OP;
-enum SLC_SESSION_OP { SLC_SESSION_ALLOC, SLC_SESSION_ERASE, SLC_SESSION_GET };
+enum SLC_SESSION_OP {
+	SLC_SESSION_ALLOC,
+	SLC_SESSION_ERASE,
+	SLC_SESSION_PUSH,
+	SLC_SESSION_GET,
+	SLC_SESSION_SET,
+	SLC_SESSION_PROCESS
+};
 typedef enum SLC_SESSION_OP SLC_SESSION_OP;
 enum SLC_IO_OP {
 	SLC_IO_OPEN,
@@ -110,9 +117,10 @@ typedef enum SLC_IO_OP SLC_IO_OP;
  * @param op Defines which operation the caller wants.
  * @param key The key (both for SET and GET)
  * @param word When adding a found word to the symbol table, the key will point to this word
- * @returns The word definition stored for the key, or NULL when it is not stored yet or op is SET and there was an error.
+ * @returns The word/var definition stored for the key, or NULL when it is not stored yet or op is SET and there was an error.
  */
 typedef wordstart* (*sym)(SLC_SYM_OP op, char *key, wordstart *word);
+// TODO: union for this?
 
 /**
  * Function-abstraction for an integer "stack".
@@ -132,20 +140,22 @@ typedef wordstart* (*sym)(SLC_SYM_OP op, char *key, wordstart *word);
 typedef uint32_t (*stack)(SLC_STACK_OP op, uint32_t param);
 
 /**
- * Function-abstraction for an integer "session-storage".
+ * Function-abstraction for a "session-storage".
  *
  * Operations:
  * 		SLC_SESSION_ALLOC allocates parameter amount of memory and returns an accessor index.
- * 		SLC_SESSION_ERASE erase the session storage (all of it)
+ * 		SLC_SESSION_ERASE erase the session storage (all of it) - all parameters are unused
- * 		SLC_SESSION_GET gets byte at the ith accessor index
+ * 		SLC_SESSION_PUSH adds the given byte (value in i) to the end of the session storage (by growing it) - j unused
- * 		SLC_SESSION_SET sets byte to have the value of b at the ith accessor index
+ * 		SLC_SESSION_GET gets byte at the ith accessor index - j unused
+ * 		SLC_SESSION_SET gets byte at the ith accessor index to be of (byte)j
+ * 		SLC_SESSION_PROCESS gets the last j bytes and moves them overriding bytes at index i, then "shrinks" the storage by j.
  *
  * @param op Defines which operation the caller wants.
- * @param i Used on SESSION_GET and is the accessor index
+ * @param i Used on SESSION_GET and is the accessor index, in case of SESSIN_ALLOC it is the amount to allocate.
- * @param b Used on SESSION_SET and is the byte to write
+ * @param j Used on SESSION_SET as the byte value and on SESSION_PROCESS as the amount of bytes to "process" / shrink.
  * @returns The accessor index in case of ALLOC (0xFFFFFFFF == -1 means error), on get it returns the store BYTE as uint32_t
  */
-typedef uint32_t (*session)(SLC_SESSION_OP op, uint32_t i, uint8_t b);
+typedef uint32_t (*session)(SLC_SESSION_OP op, uint32_t i, uint32_t j);
 
 /**
  * Function-abstraction for io connectors.
@@ -167,6 +177,7 @@ typedef uint32_t (*session)(SLC_SESSION_OP op, uint32_t i, uint8_t b);
  * @returns A handle pointer or pointer to character to read / written or closed/unlocked handle (NULL on errors). Also cmd stdout.
  */
 typedef const char* (*ioconn)(SLC_IO_OP op, const char *param);
+// TODO: union for this?
 
 /**
  * Function-abstraction for reading the source code byte-by-byte.
@@ -176,23 +187,35 @@ typedef uint8_t (*coderead)();
 /**
  * This function runs the main slc engine over a snippet of code.
  *
- * The code_src is what we start interpreting, but you can do buffered reads
+ * The code_src is the entry of what we start interpreting, but you can do (un)buffered reads in it
  * because we will use session_storage to store the source code data into memory while processing...
- * This also helps with the "include" directives using io_connector.
+ * Rem.: This also helps with the "include" directives using io_connector and do some kind of recursion maybe.
- * TODO: Investigate "what if" we start with session_storage prefilled with the initial read code?
+ * Rem.: This architecture also let us try to immediately "threaded_code" optimize the newly added word definition,
+ *       which is possible if it relies on no forward references - this is the most happy case in my opinion!
+ *
+ * The session_storage is where we process the words data (possibly introducing threaded code as early as possible).
+ * This should also let the code "allocate" some random memory too and get an offset for it (there will be no other way).
  *
  * The symbol_table not only store "words", but direct access offsets for:
  *
- * - words themselves
+ * - words themselves (direct offset)
- * - variables of the words
+ * - variables of the words (direct offset)
  * - "word ", "word(", "word[", "word{" keys show where "blocks" of that word is. TODO: what to do with multiple blocks? Use flagz?
  *
+ * The code stack is what the interpreter uses for return addresses, the data stack however is FORTH-style usual stack.
+ * The "insert_stack" collects things that we will read instead of reading the code_src AFTER a return from current word.
+ * A \0 value should be there at the end of it until we RETURN from the word - from when we start processing.
+ *
+ * The io_connector is needed so that the engine have connection for temporary and real files and things simulating those.
+ *
+ * The prefix, ender and varprefix strings really just help when you use SLC to define a compiler and you need these.
+ *
  * @param code_src The input source code to interpret / run. Code ends either with \0 or EOF.
+ * @param session_storage Can allocate and use arbitrary memory with this.
  * @param symbol_table The symbol table to use while processing.
  * @param code_stack The code stack (return addresses) to use.
  * @param data_stack The data stack (forth-like stack) to use.
  * @param insert_stack Used for temporarily expanding the input stream (one word level above current) with further words.
- * @param session_storage Can allocate and use arbitrary memory with this.
  * @param io_connector The engine uses this to open/close pipes/files and write/read them.
  * @param prefix The prefix added to the lookup of built-ins. Useful when you write a compiler with SLC. Defaults to "" (empty).
  * @param ender The character string that ends a word definition. Defaults to ";".
@@ -200,11 +223,11 @@ typedef uint8_t (*coderead)();
  */
 static inline void slc(
 	coderead code_src,
+	session session_storage,
 	sym symbol_table,
 	stack code_stack,
 	stack data_stack,
 	stack insert_stack,
-	session session_storage,
 	ioconn io_connector,
 	const char *prefix,
 	const char *ender,