mq.h

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/*
 * This file is part of LibCSS.
 * Licensed under the MIT License,
 *        http://www.opensource.org/licenses/mit-license.php
 * Copyright 2016 John-Mark Bell <jmb@netsurf-browser.org>
 */
 
#ifndef css_parse_mq_h_
#define css_parse_mq_h_
 
#include <parserutils/utils/vector.h>
#include "parse/language.h"
 
typedef struct {
    enum {
        CSS_MQ_VALUE_TYPE_NUM,
        CSS_MQ_VALUE_TYPE_DIM,
        CSS_MQ_VALUE_TYPE_IDENT,
        CSS_MQ_VALUE_TYPE_RATIO
    } type;
    union {
        css_fixed num_or_ratio; /* Where ratio is the result of a/b */
        struct {
            css_fixed len;
            uint32_t unit;
        } dim;
        lwc_string *ident;
    } data;
} css_mq_value;
 
/*
 * "name : value" is encoded as "name = value"
 * "name" is encoded by setting the operator to "bool"
 * "value op name" is encoded verbatim (with op2 set to "unused")
 * "name op value" inverts the operator to encode (i.e < becomes >=) (and sets op2 to "unused")
 * "value op name op value" is encoded using op2 and value2
 */
typedef enum {
    CSS_MQ_FEATURE_OP_BOOL, /* op only */
    CSS_MQ_FEATURE_OP_UNUSED = CSS_MQ_FEATURE_OP_BOOL, /* op2 only */
 
    CSS_MQ_FEATURE_OP_LT,
    CSS_MQ_FEATURE_OP_LTE,
    CSS_MQ_FEATURE_OP_EQ, /* op only */
    CSS_MQ_FEATURE_OP_GTE,
    CSS_MQ_FEATURE_OP_GT
} css_mq_feature_op;
 
typedef struct {
    lwc_string *name;
    css_mq_feature_op op;
    css_mq_feature_op op2;
    css_mq_value value;
    css_mq_value value2;
} css_mq_feature;
 
typedef struct css_mq_cond_or_feature css_mq_cond_or_feature;
 
typedef struct {
    uint32_t negate : 1, /* set if "not" */
         op     : 1; /* clear if "and", set if "or" */
    uint32_t nparts;
    css_mq_cond_or_feature **parts;
} css_mq_cond;
 
struct css_mq_cond_or_feature {
    enum {
        CSS_MQ_FEATURE,
        CSS_MQ_COND
    } type;
    union {
        css_mq_cond *cond;
        css_mq_feature *feat;
    } data;
};
 
typedef struct css_mq_query {
    struct css_mq_query *next;
 
    uint32_t negate_type : 1; /* set if "not type" */
    uint64_t type; /* or NULL */
 
    css_mq_cond *cond;
} css_mq_query;
 
css_error css_parse_media_query(lwc_string **strings,
        const uint8_t *mq, size_t len,
        css_mq_query **media_out);
 
css_error css__mq_parse_media_list(lwc_string **strings,
        const parserutils_vector *vector, int32_t *ctx,
        css_mq_query **media);
 
void css__mq_query_destroy(css_mq_query *media);
 
#endif