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Diffstat (limited to 'src/conditions.cpp')
| -rw-r--r-- | src/conditions.cpp | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/src/conditions.cpp b/src/conditions.cpp new file mode 100644 index 0000000..e092ddc --- /dev/null +++ b/src/conditions.cpp @@ -0,0 +1,457 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * SVG conditional attribute evaluation + * + * Authors: + * Andrius R. <knutux@gmail.com> + * Abhishek Sharma + * + * Copyright (C) 2006 authors + * + * Released under GNU GPL v2+, read the file 'COPYING' for more information. + */ + +#include <vector> +#include <set> + +#include <glibmm/ustring.h> + +#include "conditions.h" +#include "rdf.h" + +#include "object/sp-item.h" + +#include "xml/repr.h" + +typedef bool (* condition_evaluator)(SPItem const *item, gchar const *value); + +struct Condition { + gchar const *attribute; + condition_evaluator evaluator; +}; + +static bool evaluateSystemLanguage(SPItem const *item, gchar const *value); +static bool evaluateRequiredFeatures(SPItem const *item, gchar const *value); +static bool evaluateRequiredExtensions(SPItem const *item, gchar const *value); + +/* define any conditional attributes and their handler functions in this array */ +static Condition _condition_handlers[] = { + { "systemLanguage", evaluateSystemLanguage }, + { "requiredFeatures", evaluateRequiredFeatures }, + { "requiredExtensions", evaluateRequiredExtensions }, +}; + +// function which evaluates if item should be displayed +bool sp_item_evaluate(SPItem const *item) { + bool needDisplay = true; + for ( unsigned int i = 0 ; needDisplay && (i < sizeof(_condition_handlers) / sizeof(_condition_handlers[0])) ; i++ ) { + gchar const *value = item->getAttribute(_condition_handlers[i].attribute); + if ( value && !_condition_handlers[i].evaluator(item, value) ) { + needDisplay = false; + } + } + return needDisplay; +} + +#define ISALNUM(c) (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z') || ((c) >= '0' && (c) <= '9')) + +// TODO: review and modernize this function +static gchar *preprocessLanguageCode(const gchar *language_code) { + if ( nullptr == language_code || strcmp(language_code, "") == 0) + return nullptr; + + gchar *lngcode = g_strdup(language_code); + for ( unsigned int i = 0 ; i < strlen(lngcode) ; i++ ) { + if ( lngcode[i] >= 'A' && lngcode[i] <= 'Z' ) { + lngcode[i] = g_ascii_tolower(lngcode[i]); + } else if ( '_' == lngcode[i] ) { + lngcode[i] = '-'; + } else if ( !ISALNUM(lngcode[i]) && '-' != lngcode[i] ) { + // only alpha numeric characters and '-' may be contained in language code + g_free(lngcode); + return nullptr; + } + } + + return lngcode; +} + +static bool evaluateSystemLanguage(SPItem const *item, gchar const *value) { + if ( nullptr == value ) + return true; + + std::set<Glib::ustring> language_codes; + gchar *str = nullptr; + gchar **strlist = g_strsplit( value, ",", 0); + + for ( int i = 0 ; (str = strlist[i]) ; i++ ) { + str = g_strstrip(str); + gchar *lngcode = preprocessLanguageCode(str); + if (lngcode == nullptr) + continue; + language_codes.insert(lngcode); + + gchar *pos = strchr (lngcode, '-'); + if (pos) + { + // if subtag is used, primary tag is still a perfect match + *pos = 0; + if (strlen(lngcode) && language_codes.find(lngcode) == language_codes.end()) { + language_codes.insert(lngcode); + } + } + } + g_strfreev(strlist); + + if (language_codes.empty()) + return false; + + SPDocument *document = item->document; + const auto document_languages = document->getLanguages(); + + if (document_languages.size() == 0) + return false; + + for (const auto &language : document_languages) { + gchar *lngcode = preprocessLanguageCode(language.c_str()); + if (lngcode && (language_codes.find(lngcode) != language_codes.end())) { + g_free(lngcode); + return true; + } + g_free(lngcode); + } + return false; +} + +static std::vector<Glib::ustring> splitByWhitespace(gchar const *value) { + std::vector<Glib::ustring> parts; + gchar *str = nullptr; + gchar **strlist = g_strsplit( value, ",", 0); + + for ( int i = 0 ; (str = strlist[i]) ; i++ ) { + gchar *part = g_strstrip(str); + if ( 0 == *part ) + continue; + parts.emplace_back(part); + } + g_strfreev(strlist); + return parts; +} + +#define SVG11FEATURE "http://www.w3.org/TR/SVG11/feature#" +#define SVG10FEATURE "org.w3c." + +static bool evaluateSVG11Feature(gchar const *feature) { + static gchar const *_supported_features[] = { + "SVG", // incomplete "SVG-static" - missing support for "Filter" + /* SVG - user agent supports at least one of the following: + "SVG-static", "SVG-animation", "SVG-dynamic" or "SVGDOM" */ + // "SVGDOM", // not sure + /* SVGDOM - user agent supports at least one of the following: + "SVGDOM-static", "SVGDOM-animation" or "SVGDOM-dynamic" */ + "SVG-static", // incomplete - missing support for "Filter" + /* SVG-static - user agent supports the following features: + "CoreAttribute", "Structure", "ContainerAttribute", + "ConditionalProcessing", "Image", "Style", "ViewportAttribute", + "Shape", "Text", "PaintAttribute", "OpacityAttribute", + "GraphicsAttribute", "Marker", "ColorProfile", + "Gradient", "Pattern", "Clip", "Mask", "Filter", + "XlinkAttribute", "Font", "Extensibility" */ + // "SVGDOM-static", // not sure + /* SVGDOM-static - All of the DOM interfaces and methods + that correspond to SVG-static */ + // "SVG-animation", // no support + /* SVG-animation - All of the language features from "SVG-static" + plus the feature "feature#Animation" */ + // "SVGDOM-animation", // no support + /* SVGDOM-animation - All of the DOM interfaces and methods + that correspond to SVG-animation */ + // "SVG-dynamic", // no support + /* SVG-dynamic - user agent supports all "SVG-animation" and the following features: + "Hyperlinking", "Scripting", "View", "Cursor", + "GraphicalEventsAttribute", "DocumentEventsAttribute", "AnimationEventsAttribute" */ + // "SVGDOM-dynamic", // no support + /* SVGDOM-dynamic - All of the DOM interfaces and methods + that correspond to SVG-dynamic */ + "CoreAttribute", + "Structure", + "BasicStructure", + "ContainerAttribute", + "ConditionalProcessing", + "Image", + "Style", + "ViewportAttribute", // not sure + "Shape", + "Text", + "BasicText", + "PaintAttribute", + "BasicPaintAttribute", + "OpacityAttribute", + "GraphicsAttribute", + "BasicGraphicsAttribute", + "Marker", + "ColorProfile", + "Gradient", + "Pattern", + "Clip", + "BasicClip", + "Mask", + // "Filter", + // "BasicFilter", + // "DocumentEventsAttribute", + // "GraphicalEventsAttribute", + // "AnimationEventsAttribute", + // "Cursor", // not sure + "Hyperlinking", // not sure + "XlinkAttribute", // not sure + "ExternalResourcesRequired", // not sure + "View", + // "Script", + // "Animation", + "Font", + "BasicFont", + "Extensibility", // not sure + }; + + for (auto & _supported_feature : _supported_features) { + if ( 0 == strcasecmp(feature, _supported_feature) ) + return true; + } + return false; +} + +static bool evaluateSVG10Feature(gchar const *feature) { + static gchar const *_supported_features[] = { + "svg.static", // incomplete - no filter effects + "dom.svg.static", // not sure + // "svg.animation", + // "dom.svg.animation", + // "svg.dynamic", + // "dom.svg.dynamic" + // "svg.all", + // "dom.svg.all" + }; + for (auto & _supported_feature : _supported_features) { + if ( 0 == strcasecmp(feature, _supported_feature) ) + return true; + } + return false; +} + +static bool evaluateSingleFeature(gchar const *value) { + if ( nullptr == value ) + return false; + gchar const *found; + found = strstr(value, SVG11FEATURE); + if ( value == found ) + return evaluateSVG11Feature(found + strlen(SVG11FEATURE)); + found = strstr(value, SVG10FEATURE); + if ( value == found ) + return evaluateSVG10Feature(found + strlen(SVG10FEATURE)); + return false; +} + +static bool evaluateRequiredFeatures(SPItem const */*item*/, gchar const *value) { + if ( nullptr == value ) + return true; + + std::vector<Glib::ustring> parts = splitByWhitespace(value); + if (parts.empty()) + { + return false; + } + + for (auto & part : parts) { + if (!evaluateSingleFeature(part.c_str())) { + return false; + } + } + + return true; +} + +static bool evaluateRequiredExtensions(SPItem const */*item*/, gchar const *value) { + if ( nullptr == value ) + return true; + return false; +} + +/* + * Language codes and names: +aa Afar +ab Abkhazian +af Afrikaans +am Amharic +ar Arabic +as Assamese +ay Aymara +az Azerbaijani + +ba Bashkir +be Byelorussian +bg Bulgarian +bh Bihari +bi Bislama +bn Bengali; Bangla +bo Tibetan +br Breton + +ca Catalan +co Corsican +cs Czech +cy Welsh + +da Danish +de German +dz Bhutani + +el Greek +en English +eo Esperanto +es Spanish +et Estonian +eu Basque + +fa Persian +fi Finnish +fj Fiji +fo Faroese +fr French +fy Frisian + +ga Irish +gd Scots Gaelic +gl Galician +gn Guarani +gu Gujarati + +ha Hausa +he Hebrew (formerly iw) +hi Hindi +hr Croatian +hu Hungarian +hy Armenian + +ia Interlingua +id Indonesian (formerly in) +ie Interlingue +ik Inupiak +is Icelandic +it Italian +iu Inuktitut + +ja Japanese +jw Javanese + +ka Georgian +kk Kazakh +kl Greenlandic +km Cambodian +kn Kannada +ko Korean +ks Kashmiri +ku Kurdish +ky Kirghiz + +la Latin +ln Lingala +lo Laothian +lt Lithuanian +lv Latvian, Lettish + +mg Malagasy +mi Maori +mk Macedonian +ml Malayalam +mn Mongolian +mo Moldavian +mr Marathi +ms Malay +mt Maltese +my Burmese + +na Nauru +ne Nepali +nl Dutch +no Norwegian + +oc Occitan +om (Afan) Oromo +or Oriya + +pa Punjabi +pl Polish +ps Pashto, Pushto +pt Portuguese + +qu Quechua + +rm Rhaeto-Romance +rn Kirundi +ro Romanian +ru Russian +rw Kinyarwanda + +sa Sanskrit +sd Sindhi +sg Sangho +sh Serbo-Croatian +si Sinhalese +sk Slovak +sl Slovenian +sm Samoan +sn Shona +so Somali +sq Albanian +sr Serbian +ss Siswati +st Sesotho +su Sundanese +sv Swedish +sw Swahili + +ta Tamil +te Telugu +tg Tajik +th Thai +ti Tigrinya +tk Turkmen +tl Tagalog +tn Setswana +to Tonga +tr Turkish +ts Tsonga +tt Tatar +tw Twi + +ug Uighur +uk Ukrainian +ur Urdu +uz Uzbek + +vi Vietnamese +vo Volapuk + +wo Wolof + +xh Xhosa + +yi Yiddish (formerly ji) +yo Yoruba + +za Zhuang +zh Chinese +zu Zulu + */ + + +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 : |