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/*
* Copyright © 2021 Michael Smith <mikesmiffy128@gmail.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef INC_KV_H
#define INC_KV_H
#include <stdbool.h>
#include "intdefs.h"
/*
* Maximum length of a single token. Since this code is trying to avoid dynamic
* memory allocations, this arbitrary limit is chosen to accomodate all known
* "reasonable" tokens likely to come in any real files, probably.
*/
#define KV_TOKEN_MAX 512
/*
* Contains all the state associated with parsing (lexing?) a KeyValues file.
* Should be zeroed out prior to the first call (initialise with `= {0};`).
*/
struct kv_parser {
ushort line, col; /* the current line and column in the text */
char state : 7; /* internal, shouldn't usually be touched directly */
bool incomment : 1; /* internal */
ushort nestlvl; /* internal */
const char *errmsg; /* the error message, *IF* parsing just failed */
// trying to avoid dynamic allocations - valve's own parser seems to have
// a similar limit as well and our use case doesn't really need to worry
// about stupid massive values, so it's fine
char *outp;
char tokbuf[KV_TOKEN_MAX];
};
/*
* These are the tokens that can be received by a kv_parser_cb (below).
* The x-macro and string descriptions are given to allow for easy debug
* stringification. Note that this "parser" is really just lexing out these
* tokens - handling the actual structure of the file should be done in the
* callback. This is so that data can be streamed rather than all read into
* memory at once.
*/
#define KV_TOKENS(X) \
X(KV_IDENT, "ident") \
X(KV_IDENT_QUOTED, "quoted-ident") \
X(KV_VAL, "value") \
X(KV_VAL_QUOTED, "quoted-value") \
X(KV_COND_PREFIX, "cond-prefix") \
X(KV_COND_SUFFIX, "cond-suffix") \
X(KV_NEST_START, "object-start") \
X(KV_NEST_END, "object-end")
#define _ENUM(s, ignore) s,
enum kv_token { KV_TOKENS(_ENUM) };
#undef _ENUM
typedef void (*kv_parser_cb)(enum kv_token type, const char *p, uint len,
void *ctxt);
/*
* Feed a block of text into the lexer. This would usually be a block of data
* read in from a file.
*
* The lexer is reentrant and can be fed arbitrarily sized blocks of data at a
* time. The function may return early in the event of an error; a return value
* of false indicates thaat this has happened, otherwise true is returned.
*
* In the event of an error, the errmsg, line and col fields of the parser
* struct can be used for diagnostics.
*/
bool kv_parser_feed(struct kv_parser *this, const char *in, uint sz,
kv_parser_cb cb, void *ctxt);
/*
* This indicates that parsing is done; if this is called at an unexpected time,
* a parsing error will result; this is indicated in the return value as with
* kv_parser_feed.
*/
bool kv_parser_done(struct kv_parser *this);
#endif
// vi: sw=4 ts=4 noet tw=80 cc=80
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