diff options
Diffstat (limited to 'src/core/resource')
| -rw-r--r-- | src/core/resource/Resource.cpp | 46 | ||||
| -rw-r--r-- | src/core/resource/Resource.hpp | 181 | ||||
| -rw-r--r-- | src/core/resource/ResourceLocator.cpp | 103 | ||||
| -rw-r--r-- | src/core/resource/ResourceLocator.hpp | 193 |
4 files changed, 523 insertions, 0 deletions
diff --git a/src/core/resource/Resource.cpp b/src/core/resource/Resource.cpp new file mode 100644 index 0000000..349c82a --- /dev/null +++ b/src/core/resource/Resource.cpp @@ -0,0 +1,46 @@ +/* + Ousía + Copyright (C) 2014, 2015 Benjamin Paaßen, Andreas Stöckel + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "Resource.hpp" +#include "ResourceLocator.hpp" + +namespace ousia { + +/* Class Resource */ + +Resource::Resource() + : Resource(false, NullResourceLocator, ResourceType::UNKNOWN, "") +{ +} + +Resource::Resource(bool valid, const ResourceLocator &locator, + ResourceType type, const std::string &location) + : valid(valid), locator(&locator), type(type), location(location) +{ +} + +std::unique_ptr<std::istream> Resource::stream() const +{ + return locator->stream(location); +} + +/* NullResource instance */ + +const Resource NullResource{}; +} + diff --git a/src/core/resource/Resource.hpp b/src/core/resource/Resource.hpp new file mode 100644 index 0000000..1934029 --- /dev/null +++ b/src/core/resource/Resource.hpp @@ -0,0 +1,181 @@ +/* + Ousía + Copyright (C) 2014, 2015 Benjamin Paaßen, Andreas Stöckel + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +/** + * @file Resource.hpp + * + * Contains the Resource class, representing an external resource as well as + * further types used for describing resources. + * + * @author Benjamin Paaßen (bpassen@techfak.uni-bielefeld.de) + */ + +#ifndef _OUSIA_RESOURCE_HPP_ +#define _OUSIA_RESOURCE_HPP_ + +#include <map> +#include <memory> +#include <string> + +namespace ousia { + +// Forward declaration +class ResourceLocator; + +/** + * This enum contains all possible types of includable resources in Ousía. + */ +enum class ResourceType { + /** + * Unknown type. + */ + UNKNOWN, + + /** + * The resource contains a domain description. + */ + DOMAIN_DESC, + + /** + * The resource contains a typesystem description. + */ + TYPESYSTEM, + + /** + * The resource contains a simple document. + */ + DOCUMENT, + + /** + * The resource contains style attributes. + */ + ATTRIBUTES, + + /** + * The resource is a stylesheet. + */ + STYLESHEET, + + /** + * The resource contains script (note that the actual scripting language is + * not specified by the resource type). + */ + SCRIPT, + + /** + * Generic data, such as e.g. images. + */ + DATA +}; + +/** + * A Location contains the location of a Resource, e.g. a file path + * on a hard drive. Note that the 'found' flag might be set to false + * indicating that a resource was not found. + */ +class Resource { +private: + /** + * Specifies whether the resource points at a valid location or not. + */ + bool valid; + + /** + * Reference pointing at the location + */ + ResourceLocator const *locator; + + /** + * Requested type of the resource. + */ + ResourceType type; + + /** + * This is a fully qualified/canonical path to the resource found or + * in an undefined state (possibly empty) if the 'valid' flag is set + * to 'false'. + */ + std::string location; + +public: + /** + * Default constructor of the Resource class, represents an invalid + * resource. + */ + Resource(); + + /** + * Constructor of the Resource class. + * + * @param valid specifies whether the Resource is valid or not. + * @param locator specifies the resource locator that was used to locate the + * resource. + */ + Resource(bool valid, const ResourceLocator &locator, + ResourceType type, const std::string &location); + + /** + * This calls the 'stream' method of the underlying ResourceLocator that + * found this location and returns a stream containing the data of the + * Resource at this location. + * + * @return a stream containing the data of the Resource at this + * location. This has to be a unique_pointer because the current + * C++11 compiler does not yet support move semantics for + * streams. + */ + std::unique_ptr<std::istream> stream() const; + + /** + * Returns whether this resource is valid or not. + * + * @return true if the resource is valid, false otherwise. + */ + bool isValid() const { return valid; } + + /** + * Returns a reference pointing at the locator that was used to locate this + * resource. + * + * @return the locator used for locating this resource. + */ + const ResourceLocator &getLocator() const { return *locator; } + + /** + * Returns the type of the resource that was requested when the resource was + * located. + * + * @return the type of the resource. + */ + ResourceType getType() const { return type; } + + /** + * Returns a canonical location that can be used in a hash map to identify + * a resource. + */ + const std::string &getLocation() const { return location; } +}; + +/** + * Invalid resource instance. + */ +extern const Resource NullResource; +} + +#endif /* _OUSIA_RESOURCE_HPP_ */ + diff --git a/src/core/resource/ResourceLocator.cpp b/src/core/resource/ResourceLocator.cpp new file mode 100644 index 0000000..1b8490d --- /dev/null +++ b/src/core/resource/ResourceLocator.cpp @@ -0,0 +1,103 @@ +/* + Ousía + Copyright (C) 2014, 2015 Benjamin Paaßen, Andreas Stöckel + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include <sstream> + +#include "Resource.hpp" +#include "ResourceLocator.hpp" + +namespace ousia { + +/* Class ResourceLocator */ + +bool ResourceLocator::locate(Resource &resource, const std::string &path, + const ResourceType type, + const Resource &relativeTo) const +{ + if (&relativeTo.getLocator() == this) { + return doLocate(resource, path, type, relativeTo.getLocation()); + } + return doLocate(resource, path, type, ""); +} + +bool ResourceLocator::locate(Resource &resource, const std::string &path, + const ResourceType type, + const std::string &relativeTo) const +{ + return doLocate(resource, path, type, relativeTo); +} + +std::unique_ptr<std::istream> ResourceLocator::stream( + const std::string &location) const +{ + return doStream(location); +} + +/* Class StaticResourceLocator */ + +bool StaticResourceLocator::doLocate( + Resource &resource, const std::string &path, const ResourceType type, + const std::string &relativeTo) const +{ + auto it = resources.find(path); + if (it != resources.end()) { + resource = Resource(true, *this, type, path); + return true; + } + return false; +} + +std::unique_ptr<std::istream> StaticResourceLocator::doStream( + const std::string &location) const +{ + auto it = resources.find(location); + if (it != resources.end()) { + return std::unique_ptr<std::istream>{new std::stringstream{it->second}}; + } + return std::unique_ptr<std::istream>{new std::stringstream{""}}; +} + +void StaticResourceLocator::store(const std::string &path, + const std::string &data) +{ + auto it = resources.find(path); + if (it != resources.end()) { + it->second = data; + } else { + resources.emplace(path, data); + } +} + +/* Class NullResourceLocatorImpl */ + +bool NullResourceLocatorImpl::doLocate(Resource &resource, + const std::string &path, + const ResourceType type, + const std::string &relativeTo) const +{ + return false; +} +std::unique_ptr<std::istream> NullResourceLocatorImpl::doStream( + const std::string &location) const +{ + return std::unique_ptr<std::istream>{new std::stringstream{""}}; +} + +const NullResourceLocatorImpl NullResourceLocator; +} + diff --git a/src/core/resource/ResourceLocator.hpp b/src/core/resource/ResourceLocator.hpp new file mode 100644 index 0000000..c1d0807 --- /dev/null +++ b/src/core/resource/ResourceLocator.hpp @@ -0,0 +1,193 @@ +/* + Ousía + Copyright (C) 2014, 2015 Benjamin Paaßen, Andreas Stöckel + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#ifndef _OUSIA_RESOURCE_LOCATOR_HPP_ +#define _OUSIA_RESOURCE_LOCATOR_HPP_ + +#include <istream> +#include <memory> + +#include "Resource.hpp" + +namespace ousia { + +// Forward declaration +class ResourceLocator; + +/** + * A ResourceLocator is a class able to locate resources in some way, usually + * on the hard drive. + * + * We specify this as an abstract superclass to have an interface layer between + * the program core and possible future extensions in terms of resource + * locations (e.g. online resources, .zip files, etc.). + */ +class ResourceLocator { +protected: + /** + * The locate function uses this ResourceLocator to search for a given + * Resource name (path parameter). It returns a Location with the + * 'valid' flag set accordingly. + * + * @param resource reference to a Resource the will be set the the found + * location. The content of the variable will be only valid if the return + * value of this function is set to true. + * @param path is the resource name. + * @param relativeTo is an already resolved fully qualified name/canonical + * path that is to be used as base directory for this search. It is + * guaranteed that the path was produced by this locator instance. Otherwise + * this argument is set to an empty string. + * @param type is the type of this resource. + * @return true if a resource could be found, false otherwise. + */ + virtual bool doLocate(Resource &resource, const std::string &path, + const ResourceType type, + const std::string &relativeTo) const = 0; + + /** + * This method returns a stream containing the data of the resource at the + * given location. + * + * @param location is a found location, most likely from a Location. + * + * @return a stream containing the data of the Resource at this + * location. This has to be a unique_pointer because the current + * C++11 compiler does not yet support move semantics for + * streams. + */ + virtual std::unique_ptr<std::istream> doStream( + const std::string &location) const = 0; + +public: + /** + * Virtual destructor of the ResourceLocator interface. + */ + virtual ~ResourceLocator() {} + + /** + * The locate function uses this ResourceLocator to search for a given + * Resource name (path parameter). + * + * @param resource reference to a Resource the will be set the the found + * location. The content of the variable will be only valid if the return + * value of this function is set to true. + * @param path is the resource name. + * @param relativeTo is an already resolved Resource. + * @param type is the type of this resource. + * @return true if a resource could be found, false otherwise. + */ + bool locate(Resource &resource, const std::string &path, + const ResourceType type = ResourceType::UNKNOWN, + const Resource &relativeTo = NullResource) const; + + /** + * The locate function uses this ResourceLocator to search for a given + * Resource name (path parameter). + * + * @param resource reference to a Resource the will be set the the found + * location. The content of the variable will be only valid if the return + * value of this function is set to true. + * @param path is the resource name. + * @param type is the type of this resource. + * @param relativeTo is the location of an already resolved resource + * relative to which this resource should be located. + * @return true if a resource could be found, false otherwise. + */ + bool locate(Resource &resource, const std::string &path, + const ResourceType type, + const std::string &relativeTo) const; + + /** + * This method returns a stream containing the data of the resource at the + * given location. + * + * @param location is a found location, most likely from a Location. + * + * @return a stream containing the data of the Resource at this + * location. This has to be a unique_pointer because the current + * C++11 compiler does not yet support move semantics for + * streams. + */ + std::unique_ptr<std::istream> stream(const std::string &location) const; +}; + +/** + * The StaticResourceLocator class stores a set of predefined resources in + * memory and allows to return these. + */ +class StaticResourceLocator : public ResourceLocator { +private: + /** + * Map containing the paths and the corresponding stored data. + */ + std::map<std::string, std::string> resources; + +protected: + /** + * Always returns false. + */ + bool doLocate(Resource &resource, const std::string &path, + const ResourceType type, + const std::string &relativeTo) const override; + + /** + * Returns an input stream containing an empty string. + */ + std::unique_ptr<std::istream> doStream( + const std::string &location) const override; + +public: + /** + * Stores static (string) data for the given path. + * + * @param path is the path the resource should be stored with. + * @param data is the data that should be stored for that path. + */ + void store(const std::string &path, const std::string &data); +}; + +/** + * Implementation of the NullResourceLocator - contains a default implementation + * of the ResourceLocator class that does nothing. This class is e.g. used in + * the default constructor of the resource class. A instance of the class is + * provided as "NullResourceLocator". + */ +class NullResourceLocatorImpl : public ResourceLocator { +protected: + /** + * Always returns false. + */ + bool doLocate(Resource &resource, const std::string &path, + const ResourceType type, + const std::string &relativeTo) const override; + + /** + * Returns an input stream containing an empty string. + */ + std::unique_ptr<std::istream> doStream( + const std::string &location) const override; +}; + +/** + * The NullResourceLocator is used as a fallback for invalid Resources. + */ +extern const NullResourceLocatorImpl NullResourceLocator; +} + +#endif /* _RESOURCE_LOCATOR_HPP_ */ + |