[ovs.git] / ovn / lib / lex.h

/*
 * Copyright (c) 2015 Nicira, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef OVN_LEX_H
#define OVN_LEX_H 1

/* OVN lexical analyzer
 * ====================
 *
 * This is a simple lexical analyzer (or tokenizer) for OVN match expressions
 * and ACLs. */

#include "meta-flow.h"

struct ds;

/* Token type. */
enum lex_type {
    LEX_T_END,                  /* end of input */

    /* Tokens with auxiliary data. */
    LEX_T_ID,                   /* foo */
    LEX_T_STRING,               /* "foo" */
    LEX_T_INTEGER,              /* 12345 or 1.2.3.4 or ::1 or 01:02:03:04:05 */
    LEX_T_MASKED_INTEGER,       /* 12345/10 or 1.2.0.0/16 or ::2/127 or... */
    LEX_T_ERROR,                /* invalid input */

    /* Bare tokens. */
    LEX_T_LPAREN,               /* ( */
    LEX_T_RPAREN,               /* ) */
    LEX_T_LCURLY,               /* { */
    LEX_T_RCURLY,               /* } */
    LEX_T_LSQUARE,              /* [ */
    LEX_T_RSQUARE,              /* ] */
    LEX_T_EQ,                   /* == */
    LEX_T_NE,                   /* != */
    LEX_T_LT,                   /* < */
    LEX_T_LE,                   /* <= */
    LEX_T_GT,                   /* > */
    LEX_T_GE,                   /* >= */
    LEX_T_LOG_NOT,              /* ! */
    LEX_T_LOG_AND,              /* && */
    LEX_T_LOG_OR,               /* || */
    LEX_T_ELLIPSIS,             /* .. */
    LEX_T_COMMA,                /* , */
    LEX_T_SEMICOLON,            /* ; */
    LEX_T_EQUALS,               /* = */
    LEX_T_EXCHANGE,             /* <-> */
    LEX_T_DECREMENT,            /* -- */
};

/* Subtype for LEX_T_INTEGER and LEX_T_MASKED_INTEGER tokens.
 *
 * These do not change the semantics of a token; instead, they determine the
 * format used when a token is serialized back to a text form.  That's
 * important because 3232268289 is meaningless to a human whereas 192.168.128.1
 * has some actual significance. */
enum lex_format {
    LEX_F_DECIMAL,
    LEX_F_HEXADECIMAL,
    LEX_F_IPV4,
    LEX_F_IPV6,
    LEX_F_ETHERNET,
};
const char *lex_format_to_string(enum lex_format);

/* A token.
 *
 * 's' is owned by the token. */
struct lex_token {
    enum lex_type type;         /* One of LEX_*. */
    char *s;                    /* LEX_T_ID, LEX_T_STRING, LEX_T_ERROR only. */
    enum lex_format format;     /* LEX_T_INTEGER, LEX_T_MASKED_INTEGER only. */
    union mf_subvalue value;    /* LEX_T_INTEGER, LEX_T_MASKED_INTEGER only. */
    union mf_subvalue mask;     /* LEX_T_MASKED_INTEGER only. */
};

void lex_token_init(struct lex_token *);
void lex_token_destroy(struct lex_token *);
void lex_token_swap(struct lex_token *, struct lex_token *);

void lex_token_format(const struct lex_token *, struct ds *);
const char *lex_token_parse(struct lex_token *, const char *input,
                            const char **startp);

/* A lexical analyzer. */
struct lexer {
    const char *input;          /* Remaining input (not owned by lexer). */
    const char *start;          /* Start of current token in 'input'. */
    struct lex_token token;     /* Current token (owned by lexer). */
};

void lexer_init(struct lexer *, const char *input);
void lexer_destroy(struct lexer *);

enum lex_type lexer_get(struct lexer *);
enum lex_type lexer_lookahead(const struct lexer *);
bool lexer_match(struct lexer *, enum lex_type);
bool lexer_match_id(struct lexer *, const char *id);
bool lexer_is_int(const struct lexer *);
bool lexer_get_int(struct lexer *, int *value);

#endif /* ovn/lex.h */
Commit	Line	Data
10b1662b BP	1	/*
	2	* Copyright (c) 2015 Nicira, Inc.
	3	*
	4	* Licensed under the Apache License, Version 2.0 (the "License");
	5	* you may not use this file except in compliance with the License.
	6	* You may obtain a copy of the License at:
	7	*
	8	* http://www.apache.org/licenses/LICENSE-2.0
	9	*
	10	* Unless required by applicable law or agreed to in writing, software
	11	* distributed under the License is distributed on an "AS IS" BASIS,
	12	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	13	* See the License for the specific language governing permissions and
	14	* limitations under the License.
	15	*/
	16
	17	#ifndef OVN_LEX_H
	18	#define OVN_LEX_H 1
	19
	20	/* OVN lexical analyzer
	21	* ====================
	22	*
	23	* This is a simple lexical analyzer (or tokenizer) for OVN match expressions
	24	* and ACLs. */
	25
	26	#include "meta-flow.h"
	27
	28	struct ds;
	29
	30	/* Token type. */
	31	enum lex_type {
	32	LEX_T_END, /* end of input */
	33
	34	/* Tokens with auxiliary data. */
	35	LEX_T_ID, /* foo */
	36	LEX_T_STRING, /* "foo" */
	37	LEX_T_INTEGER, /* 12345 or 1.2.3.4 or ::1 or 01:02:03:04:05 */
	38	LEX_T_MASKED_INTEGER, /* 12345/10 or 1.2.0.0/16 or ::2/127 or... */
	39	LEX_T_ERROR, /* invalid input */
	40
	41	/* Bare tokens. */
	42	LEX_T_LPAREN, /* ( */
	43	LEX_T_RPAREN, /* ) */
	44	LEX_T_LCURLY, /* { */
	45	LEX_T_RCURLY, /* } */
	46	LEX_T_LSQUARE, /* [ */
	47	LEX_T_RSQUARE, /* ] */
	48	LEX_T_EQ, /* == */
	49	LEX_T_NE, /* != */
	50	LEX_T_LT, /* < */
	51	LEX_T_LE, /* <= */
	52	LEX_T_GT, /* > */
	53	LEX_T_GE, /* >= */
	54	LEX_T_LOG_NOT, /* ! */
	55	LEX_T_LOG_AND, /* && */
	56	LEX_T_LOG_OR, /* \|\| */
	57	LEX_T_ELLIPSIS, /* .. */
	58	LEX_T_COMMA, /* , */
	59	LEX_T_SEMICOLON, /* ; */
	60	LEX_T_EQUALS, /* = */
a20c96c6	61	LEX_T_EXCHANGE, /* <-> */
56091efe	62	LEX_T_DECREMENT, /* -- */
10b1662b BP	63	};
	64
	65	/* Subtype for LEX_T_INTEGER and LEX_T_MASKED_INTEGER tokens.
	66	*
	67	* These do not change the semantics of a token; instead, they determine the
	68	* format used when a token is serialized back to a text form. That's
	69	* important because 3232268289 is meaningless to a human whereas 192.168.128.1
	70	* has some actual significance. */
	71	enum lex_format {
	72	LEX_F_DECIMAL,
	73	LEX_F_HEXADECIMAL,
	74	LEX_F_IPV4,
	75	LEX_F_IPV6,
	76	LEX_F_ETHERNET,
	77	};
363b5330	78	const char *lex_format_to_string(enum lex_format);
10b1662b BP	79
	80	/* A token.
	81	*
	82	* 's' is owned by the token. */
	83	struct lex_token {
	84	enum lex_type type; /* One of LEX_. /
	85	char s; / LEX_T_ID, LEX_T_STRING, LEX_T_ERROR only. */
	86	enum lex_format format; /* LEX_T_INTEGER, LEX_T_MASKED_INTEGER only. */
	87	union mf_subvalue value; /* LEX_T_INTEGER, LEX_T_MASKED_INTEGER only. */
	88	union mf_subvalue mask; /* LEX_T_MASKED_INTEGER only. */
	89	};
	90
	91	void lex_token_init(struct lex_token *);
	92	void lex_token_destroy(struct lex_token *);
	93	void lex_token_swap(struct lex_token , struct lex_token );
	94
3d611299	95	void lex_token_format(const struct lex_token , struct ds );
10b1662b BP	96	const char lex_token_parse(struct lex_token , const char *input,
	97	const char **startp);
	98
	99	/* A lexical analyzer. */
	100	struct lexer {
	101	const char input; / Remaining input (not owned by lexer). */
	102	const char start; / Start of current token in 'input'. */
	103	struct lex_token token; /* Current token (owned by lexer). */
	104	};
	105
	106	void lexer_init(struct lexer , const char input);
	107	void lexer_destroy(struct lexer *);
	108
	109	enum lex_type lexer_get(struct lexer *);
27912fdb	110	enum lex_type lexer_lookahead(const struct lexer *);
10b1662b	111	bool lexer_match(struct lexer *, enum lex_type);
27912fdb	112	bool lexer_match_id(struct lexer , const char id);
558ec83d BP	113	bool lexer_is_int(const struct lexer *);
558ec83d BP	114	bool lexer_get_int(struct lexer , int value);
10b1662b BP	115
10b1662b BP	116	#endif /* ovn/lex.h */