--- a/src/lib/lexer.h Wed Oct 08 22:05:13 2008 +0300
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,118 +0,0 @@
-#ifndef LIB_LEXER_H
-#define LIB_LEXER_H
-
-/*
- * Simple FSM lexing
- *
- * The lexer is implemented as a Finite State Machine, consisting for a number of states, which then contain a set of
- * transitions, which move the lexer from state to state based on each char of input at a time.
- *
- * Whenever the state changes, the token callback is triggered with the collected token data.
- */
-
-/*
- * Transition flags
- */
-enum lex_transition_flags {
- LEX_TRANS_DEFAULT = 0x01,
- LEX_TRANS_FINAL = 0x02,
-};
-
-/*
- * A transition from one state to another.
- */
-struct lex_transition {
- // applies to chars [left, right]
- char left, right;
-
- // flags from lex_transition_flags
- char flags;
-
- // next state to enter
- int next_state;
-};
-
-/*
- * State flags
- */
-enum lex_state_flags {
- LEX_STATE_END = 0x01;
-};
-
-/*
- * A state
- */
-struct lex_state {
- // the state name (for debugging)
- const char *name;
-
- // flags from lex_state_flags
- char flags;
-
- // list of transitions for this state, terminated by a transition with next_state=0
- struct lex_transition *trans_list;
-};
-
-/*
- * Lex machine
- */
-struct lex {
- // number of states
- size_t state_count;
-
- // array of lex_states, indexable by the state id.
- struct lex_state *state_list;
-
- /*
- * Core token handler. Everytime a full token is lexed (i.e. the state changes), this will be called.
- * `this_token` represents the full token that was parsed, and `token_data` is the token's value. `next_token`
- * is the state that terminated this token, and `prev_token` was the token before this one.
- *
- * `token_data` is a buffer allocated by the lexer that the actual input data is copied into. Thence, it can be
- * modified, as its contents will be replaced by the next token. Hence, if you need to keep hold of it, copy it.
- *
- * Return zero to have lexing continue, nonzero to stop lexing.
- */
- int (*token_fn) (int this_token, char *token_data, int next_token, int prev_token, void *arg);
-
- /*
- * Called on every char handled by the lexer. `this_token` is the state of the token that the char belongs to.
- *
- * Return zero to have lexing continue, nonzero to stop lexing.
- */
- int (*char_fn) (int this_token, char token_char, void *arg);
-
- /*
- * Called when the end of input has been reached, `last_token` is the state that we terminated in.
- *
- * Return zero to indiciate that the input was valid, nonzero to indicate an error.
- */
- int (*end_fn) (int last_token, void *arg);
-};
-
-/*
- * Helper macros for building the state_list
- */
-#define LEX_STATE(enum_val) { #enum_val, 0,
-#define LEX_STATE_END(enum_val) { #enum_val, LEX_STATE_END,
-
- #define LEX_CHAR(c, to) { c, c, 0, to },
- #define LEX_RANGE(l, r, to) { l, r, 0, to },
- #define LEX_ALPHA(to) LEX_RANGE('a', 'z', to), LEX_RANGE('A', 'Z', to)
- #define LEX_NUMBER(to) LEX_RANGE('0', '9', to)
- #define LEX_ALNUM(to) LEX_ALPHA(to), LEX_NUMBER(to), LEX_CHAR('-', to), LEX_CHAR('_', to)
- #define LEX_WHITESPACE(to) LEX_CHAR(' ', to), LEX_CHAR('\n', to), LEX_CHAR('\t', to)
-
- #define LEX_DEFAULT(to) { 0, 0, LEX_TRANS_DEFAULT, to } \
- }
- #define LEX_END { 0, 0, 0, 0 } \
- }
-
-/*
- * Lex it!
- *
- * Return zero to indiciate that the input was valid, nonzero otherwise.
- */
-int lexer (const struct lex *lex, const char *input, void *arg);
-
-#endif /* LIB_LEXER_H */