core: implement basic XDG Base Specification support

6 files changed, 199 insertions, 2 deletions

diff --git a/src/environment.cpp b/src/environment.cpp
new file mode 100644
index 0000000..2051573
--- /dev/null
+++ b/src/environment.cpp
@@ -0,0 +1,73 @@
+#include "environment.hpp"
+
+#include <iostream>
+#include <string>
+
+namespace wanda
+{
+
+environment::environment(char const *const *env)
+{
+    if (!env)
+    {
+        return;
+    }
+
+    std::string buffer{};
+    for (; *env != nullptr; ++env)
+    {
+        buffer = *env;
+        int split_point = buffer.find('=');
+        if (split_point != std::string::npos)
+        {
+            m_cache[buffer.substr(0, split_point)] = buffer.substr(split_point + 1);
+        }
+    }
+}
+
+std::string & environment::operator[](std::string const & variable)
+{
+    return m_cache[variable];
+}
+
+std::string const & environment::operator[](std::string const & variable) const
+{
+    static std::string const empty{};
+    if(auto needle = m_cache.find(variable); needle != cend())
+    {
+        return needle->second;
+    }
+    return empty;
+}
+
+environment::iterator environment::begin()
+{
+    return m_cache.begin();
+}
+
+environment::const_iterator environment::begin() const
+{
+    return m_cache.begin();
+}
+
+environment::const_iterator environment::cbegin() const
+{
+    return m_cache.cbegin();
+}
+
+environment::iterator environment::end()
+{
+    return m_cache.end();
+}
+
+environment::const_iterator environment::end() const
+{
+    return m_cache.end();
+}
+
+environment::const_iterator environment::cend() const
+{
+    return m_cache.cend();
+}
+
+} // namespace wanda
\ No newline at end of file
diff --git a/src/environment.hpp b/src/environment.hpp
new file mode 100644
index 0000000..a6322cb
--- /dev/null
+++ b/src/environment.hpp
@@ -0,0 +1,39 @@
+#ifndef WANDA_ENVIRONMENT_HPP
+#define WANDA_ENVIRONMENT_HPP
+
+#include <unistd.h>
+
+#include <map>
+#include <string>
+
+namespace wanda
+{
+
+struct environment
+{
+    using map_type = std::map<std::string, std::string>;
+    using iterator = map_type::iterator;
+    using const_iterator = map_type::const_iterator;
+    using reference = map_type::reference;
+    using const_reference = map_type::const_reference;
+
+    explicit environment(char const *const *env = ::environ);
+
+    std::string &operator[](std::string const &variable);
+    std::string const &operator[](std::string const &variable) const;
+
+    iterator begin();
+    const_iterator begin() const;
+    const_iterator cbegin() const;
+
+    iterator end();
+    const_iterator end() const;
+    const_iterator cend() const;
+
+  private:
+    map_type m_cache{};
+};
+
+} // namespace wanda
+
+#endif
\ No newline at end of file
diff --git a/src/wandac.cpp b/src/wandac.cpp
index 8e068ae..db072ec 100644
--- a/src/wandac.cpp
+++ b/src/wandac.cpp
@@ -1,4 +1,6 @@
 #include "control_connection.hpp"
+#include "environment.hpp"
+#include "xdg.hpp"
 
 #include <boost/asio.hpp>
 
@@ -18,6 +20,7 @@ struct commander : wanda::control_connection::listener, std::enable_shared_from_
 
     void start()
     {
+        std::clog << "[commander::start] Starting commander on socket '" << m_endpoint.path() << "'\n";
         m_socket.async_connect(m_endpoint, [&](auto const &error) {
             if (error)
             {
@@ -25,6 +28,7 @@ struct commander : wanda::control_connection::listener, std::enable_shared_from_
             }
             else
             {
+                std::clog << "[commander::start] Control connection established\n";
                 m_connection = wanda::make_control_connection(std::move(m_socket));
                 m_connection->start();
                 send("C:HELLO:1.0.0\n");
@@ -56,8 +60,12 @@ struct commander : wanda::control_connection::listener, std::enable_shared_from_
 
 int main()
 {
+    auto environment = wanda::environment{};
+    auto interface = wanda::xdg_path_for(wanda::xdg_directory::runtime_dir, environment) / ".wanda_interface";
     auto service = boost::asio::io_service{};
-    auto command_processor = commander{service, std::filesystem::path{".wanda_interface"}};
+
+    std::clog << "[wandac::main] Initializing commander for socket '" << interface.native() << "'\n";    
+    auto command_processor = commander{service, interface};
 
     command_processor.start();
 
diff --git a/src/wandad.cpp b/src/wandad.cpp
index 169efd9..04f3394 100644
--- a/src/wandad.cpp
+++ b/src/wandad.cpp
@@ -1,8 +1,10 @@
 #include "control_interface.hpp"
+#include "environment.hpp"
 #include "filesystem.hpp"
 #include "optional.hpp"
 #include "setting.hpp"
 #include "wallpaper.hpp"
+#include "xdg.hpp"
 
 #include <boost/asio.hpp>
 
@@ -39,7 +41,10 @@ int main()
     wanda::set_wallpaper(wallpaper);
 
     auto service = boost::asio::io_service{};
-    auto interface = wanda::make_interface(service, ".wanda_interface");
+    auto socket_path = wanda::xdg_path_for(wanda::xdg_directory::runtime_dir, wanda::environment{}) / ".wanda_interface";
+
+    std::clog << "[wandad::main] Initializing control interface on socket '" << socket_path.native() << "'\n";
+    auto interface = wanda::make_interface(service, socket_path);
     auto status = interface->start();
 
     if (status)
diff --git a/src/xdg.cpp b/src/xdg.cpp
new file mode 100644
index 0000000..9293151
--- /dev/null
+++ b/src/xdg.cpp
@@ -0,0 +1,47 @@
+#include "xdg.hpp"
+
+#include <unistd.h>
+
+namespace wanda
+{
+
+std::string xdg_variable(xdg_directory directory)
+{
+    switch (directory)
+    {
+    case xdg_directory::data_home:
+        return "XDG_DATA_HOME";
+    case xdg_directory::config_home:
+        return "XDG_CONFIG_HOME";
+    case xdg_directory::cache_home:
+        return "XDG_CACHE_HOME";
+    case xdg_directory::runtime_dir:
+        return "XDG_RUNTIME_DIR";
+    }
+    return "XDG_INVALID_PATH";
+}
+
+std::filesystem::path xdg_path_for(xdg_directory directory, environment const &environment)
+{
+    if (auto path = environment[xdg_variable(directory)]; !path.empty())
+    {
+        return path;
+    }
+
+    auto home = std::filesystem::path{environment["HOME"]};
+    switch (directory)
+    {
+    case xdg_directory::data_home:
+        return home / ".local/share";
+    case xdg_directory::config_home:
+        return home / ".config";
+    case xdg_directory::cache_home:
+        return home / ".cache";
+    case xdg_directory::runtime_dir:
+        return std::filesystem::path{"/run/user"} / std::to_string(::getuid());
+    }
+
+    return "";
+}
+
+} // namespace wanda
\ No newline at end of file
diff --git a/src/xdg.hpp b/src/xdg.hpp
new file mode 100644
index 0000000..a5dace0
--- /dev/null
+++ b/src/xdg.hpp
@@ -0,0 +1,25 @@
+#ifndef WANDA_XDG_HPP
+#define WANDA_XDG_HPP
+
+#include "environment.hpp"
+
+#include <cstddef>
+#include <filesystem>
+#include <type_traits>
+
+namespace wanda
+{
+enum struct xdg_directory : std::underlying_type_t<std::byte>
+{
+    data_home,
+    config_home,
+    cache_home,
+    runtime_dir,
+};
+
+std::string xdg_variable(xdg_directory directory);
+
+std::filesystem::path xdg_path_for(xdg_directory directory, environment const &environment);
+} // namespace wanda
+
+#endif
\ No newline at end of file