1 /*
2 * Licensed under the MIT License,
3 * http://www.opensource.org/licenses/mit-license.php
4 * Copyright 2010 The NetSurf Browser Project.
5 */
6
7 #include <assert.h>
8 #include <string.h>
9
10 #include "bytecode/bytecode.h"
11 #include "bytecode/opcodes.h"
12 #include "parse/properties/properties.h"
13 #include "parse/properties/utils.h"
14
15 /**
16 * Parse opacity
17 *
18 * \param c Parsing context
19 * \param vector Vector of tokens to process
20 * \param ctx Pointer to vector iteration context
21 * \param result resulting style
22 * \return CSS_OK on success,
23 * CSS_NOMEM on memory exhaustion,
24 * CSS_INVALID if the input is not valid
25 *
26 * Post condition: \a *ctx is updated with the next token to process
27 * If the input is invalid, then \a *ctx remains unchanged.
28 */
css__parse_opacity(css_language * c,const parserutils_vector * vector,int * ctx,css_style * result)29 css_error css__parse_opacity(css_language *c,
30 const parserutils_vector *vector, int *ctx,
31 css_style *result)
32 {
33 int orig_ctx = *ctx;
34 css_error error;
35 const css_token *token;
36 bool match;
37
38 token = parserutils_vector_iterate(vector, ctx);
39 if ((token == NULL) || ((token->type != CSS_TOKEN_IDENT) && (token->type != CSS_TOKEN_NUMBER))) {
40 *ctx = orig_ctx;
41 return CSS_INVALID;
42 }
43
44 if ((token->type == CSS_TOKEN_IDENT) && (lwc_string_caseless_isequal(token->idata, c->strings[INHERIT], &match) == lwc_error_ok && match)) {
45 error = css_stylesheet_style_inherit(result, CSS_PROP_OPACITY);
46 } else if (token->type == CSS_TOKEN_NUMBER) {
47 css_fixed num = 0;
48 size_t consumed = 0;
49
50 num = css__number_from_lwc_string(token->idata, false, &consumed);
51 /* Invalid if there are trailing characters */
52 if (consumed != lwc_string_length(token->idata)) {
53 *ctx = orig_ctx;
54 return CSS_INVALID;
55 }
56
57 /* Clamp to range [0,1] */
58 if (num < 0)
59 num = 0;
60 if (num > INTTOFIX(1))
61 num = INTTOFIX(1);
62
63 error = css__stylesheet_style_appendOPV(result, CSS_PROP_OPACITY, 0, OPACITY_SET);
64 if (error != CSS_OK) {
65 *ctx = orig_ctx;
66 return error;
67 }
68
69 error = css__stylesheet_style_append(result, num);
70 } else {
71 error = CSS_INVALID;
72 }
73
74 if (error != CSS_OK)
75 *ctx = orig_ctx;
76
77 return error;
78 }
79
80