obs-studio/libobs/util/lexer.h

/******************************************************************************
  Copyright (c) 2013 by Hugh Bailey <obs.jim@gmail.com>

  This software is provided 'as-is', without any express or implied
  warranty. In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

     1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.

     2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.

     3. This notice may not be removed or altered from any source
     distribution.
******************************************************************************/

#ifndef LEXER_H
#define LEXER_H

#include "c99defs.h"
#include "dstr.h"
#include "darray.h"

#ifdef __cplusplus
extern "C" {
#endif

/* ------------------------------------------------------------------------- */
/* string reference (string segment within an already existing array) */

struct strref {
	const char *array;
	size_t len;
};

static inline void strref_clear(struct strref *dst)
{
	dst->array = NULL;
	dst->len   = 0;
}

static inline void strref_set(struct strref *dst, const char *array, size_t len)
{
	dst->array = array;
	dst->len   = len;
}

static inline void strref_copy(struct strref *dst, const struct strref *src)
{
	dst->array = src->array;
	dst->len   = src->len;
}

static inline void strref_add(struct strref *dst, const struct strref *t)
{
	if (!dst->array)
		strref_copy(dst, t);
	else
		dst->len += t->len;
}

static inline bool strref_isempty(const struct strref *str)
{
	if (!str->array || !str->len)
		return true;
	if (!*str->array)
		return true;

	return false;
}

EXPORT int strref_cmp(const struct strref *str1, const char *str2);
EXPORT int strref_cmpi(const struct strref *str1, const char *str2);
EXPORT int strref_cmp_strref(const struct strref *str1,
		const struct strref *str2);
EXPORT int strref_cmpi_strref(const struct strref *str1,
		const struct strref *str2);

/* ------------------------------------------------------------------------- */

EXPORT bool valid_int_str(const char *str, size_t n);
EXPORT bool valid_float_str(const char *str, size_t n);

static inline bool valid_int_strref(const struct strref *str)
{
	return valid_int_str(str->array, str->len);
}

static inline bool valid_float_strref(const struct strref *str)
{
	return valid_float_str(str->array, str->len);
}

static inline bool is_whitespace(char ch)
{
	return ch == ' ' || ch == '\r' || ch == '\t' || ch == '\n';
}

static inline bool is_newline(char ch)
{
	return ch == '\r' || ch == '\n';
}

static inline bool is_space_or_tab(const char ch)
{
	return ch == ' ' || ch == '\t';
}

static inline bool is_newline_pair(char ch1, char ch2)
{
	return (ch1 == '\r' && ch2 == '\n') ||
	       (ch1 == '\n' && ch2 == '\r');
}

static inline int newline_size(const char *array)
{
	if (strncmp(array, "\r\n", 2) == 0 || strncmp(array, "\n\r", 2) == 0)
		return 2;
	else if (*array == '\r' || *array == '\n')
		return 1;

	return 0;
}

/* ------------------------------------------------------------------------- */

/* 
 * A "base" token is one of four things:
 *   1.) A sequence of alpha characters
 *   2.) A sequence of numeric characters
 *   3.) A single whitespace character if whitespace is not ignored
 *   4.) A single character that does not fall into the above 3 categories
 */

enum base_token_type {
	BASETOKEN_NONE,
	BASETOKEN_ALPHA,
	BASETOKEN_DIGIT,
	BASETOKEN_WHITESPACE,
	BASETOKEN_OTHER,
};

struct base_token {
	struct strref text;
	enum base_token_type type;
	bool passed_whitespace;
};

static inline void base_token_clear(struct base_token *t)
{
	memset(t, 0, sizeof(struct base_token));
}

static inline void base_token_copy(struct base_token *dst,
		struct base_token *src)
{
	memcpy(dst, src, sizeof(struct base_token));
}

/* ------------------------------------------------------------------------- */

#define LEVEL_ERROR   0
#define LEVEL_WARNING 1

struct error_item {
	char *error;
	const char *file;
	uint32_t row, column;
	int level;
};

static inline void error_item_init(struct error_item *ei)
{
	memset(ei, 0, sizeof(struct error_item));
}

static inline void error_item_free(struct error_item *ei)
{
	bfree(ei->error);
	error_item_init(ei);
}

static inline void error_item_array_free(struct error_item *array, size_t num)
{
	size_t i;
	for (i = 0; i < num; i++)
		error_item_free(array+i);
}

/* ------------------------------------------------------------------------- */

struct error_data {
	DARRAY(struct error_item) errors;
};

static inline void error_data_init(struct error_data *data)
{
	da_init(data->errors);
}

static inline void error_data_free(struct error_data *data)
{
	error_item_array_free(data->errors.array, data->errors.num);
	da_free(data->errors);
}

static inline const struct error_item *error_data_item(struct error_data *ed,
		size_t idx)
{
	return ed->errors.array+idx;
}

EXPORT char *error_data_buildstring(struct error_data *ed);

EXPORT void error_data_add(struct error_data *ed, const char *file,
		uint32_t row, uint32_t column, const char *msg, int level);

static inline size_t error_data_type_count(struct error_data *ed,
		int type)
{
	size_t count = 0, i;
	for (i = 0; i < ed->errors.num; i++) {
		if (ed->errors.array[i].level == type)
			count++;
	}

	return count;
}

static inline bool error_data_has_errors(struct error_data *ed)
{
	size_t i;
	for (i = 0; i < ed->errors.num; i++)
		if (ed->errors.array[i].level == LEVEL_ERROR)
			return true;

	return false;
}

/* ------------------------------------------------------------------------- */

struct lexer {
	char *text;
	const char *offset;
};

static inline void lexer_init(struct lexer *lex)
{
	memset(lex, 0, sizeof(struct lexer));
}

static inline void lexer_free(struct lexer *lex)
{
	bfree(lex->text);
	lexer_init(lex);
}

static inline void lexer_start(struct lexer *lex, const char *text)
{
	lexer_free(lex);
	lex->text   = bstrdup(text);
	lex->offset = lex->text;
}

static inline void lexer_start_move(struct lexer *lex, char *text)
{
	lexer_free(lex);
	lex->text   = text;
	lex->offset = lex->text;
}

static inline void lexer_reset(struct lexer *lex)
{
	lex->offset = lex->text;
}

EXPORT bool lexer_getbasetoken(struct lexer *lex, struct base_token *t,
		bool ignore_whitespace);

EXPORT void lexer_getstroffset(const struct lexer *lex, const char *str,
		uint32_t *row, uint32_t *col);

#ifdef __cplusplus
}
#endif

#endif