Refactor: Relocated Unix system-level config to libdeng2

Moved DD_Unix_GetConfigValue() into a proper class called
UnixInfo in libdeng2. The App instance will create one on
Unix platforms and host it for the lifetime of the application.
This fixes the issue of re-parsing the Info files every time
the config values were queried.

doomsday/engine/portable/src/library.c

@@ -90,7 +90,7 @@ static void getBundlePath(char* path, size_t len)
 # endif
 
     // Check Unix-specific config files.
-    DD_Unix_GetConfigValue("paths", "libdir", path, len);
+    UnixInfo_GetConfigValue("paths", "libdir", path, len);
 #endif
 }
 #endif

doomsday/engine/portable/src/sys_reslocator.c

@@ -590,7 +590,7 @@ static void createPackagesResourceNamespace(void)
     {
         // Check the system-level config files.
         filename_t fn;
-        if(DD_Unix_GetConfigValue("paths", "iwaddir", fn, FILENAME_T_MAXLEN))
+        if(UnixInfo_GetConfigValue("paths", "iwaddir", fn, FILENAME_T_MAXLEN))
         {
             doomWadDir = Str_Set(Str_New(), fn);
         }

doomsday/engine/unix/include/dd_uinit.h

@@ -53,15 +53,6 @@ extern application_t app;
 boolean DD_Unix_Init(int argc, char** argv);
 void DD_Shutdown(void);
 
-/**
- * @note This implementation re-parses the entire config file on each call, so
- * it is not useful for performance-critical or high volume usage.
- *
- * @return @c true, if the found config value was written to @a dest, otherwise
- * @c false.
- */
-boolean DD_Unix_GetConfigValue(const char* configFile, const char* key, char* dest, size_t destLen);
-
 #ifdef __cplusplus
 }
 #endif

doomsday/engine/unix/src/dd_uinit.c

@@ -313,7 +313,7 @@ static void determineGlobalPaths(application_t* app)
         strncpy(ddBasePath, DENG_BASE_DIR, FILENAME_T_MAXLEN);
 #endif
         // Also check the system config files.
-        DD_Unix_GetConfigValue("paths", "basedir", ddBasePath, FILENAME_T_MAXLEN);
+        UnixInfo_GetConfigValue("paths", "basedir", ddBasePath, FILENAME_T_MAXLEN);
     }
     Dir_CleanPath(ddBasePath, FILENAME_T_MAXLEN);
     Dir_MakeAbsolutePath(ddBasePath, FILENAME_T_MAXLEN);
@@ -437,45 +437,3 @@ void DD_Shutdown(void)
     Library_Shutdown();
     DisplayMode_Shutdown();
 }
-
-boolean DD_Unix_GetConfigValue(const char* configFile, const char* key, char* dest, size_t destLen)
-{
-    Info* info;
-    char buf[512];
-    ddstring_t* p;    
-    boolean success = false;
-
-    // Maybe it is in the user's .doomsday dir.
-    p = Str_New();
-    Str_Appendf(p, "~/.doomsday/%s", configFile);
-    F_MakeAbsolute(p, p);
-    info = Info_NewFromFile(Str_Text(p));
-    if(info)
-    {
-        if(Info_FindValue(info, key, buf, sizeof(buf)))
-        {
-            strncpy(dest, buf, destLen);
-            success = true;
-            goto cleanup;
-        }
-    }
-
-    // Check for a config file for the library path.
-    Str_Clear(p);
-    Str_Appendf(p, "/etc/doomsday/%s", configFile);
-    info = Info_NewFromFile(Str_Text(p));
-    if(info)
-    {
-        if(Info_FindValue(info, key, buf, sizeof(buf)))
-        {
-            strncpy(dest, buf, destLen);
-            success = true;
-            goto cleanup;
-        }
-    }
-
-cleanup:
-    Info_Delete(info);
-    Str_Delete(p);
-    return success;
-}

doomsday/libdeng2/include/de/UnixInfo

@@ -0,0 +1 @@
+#include "core/unixinfo.h"

doomsday/libdeng2/include/de/c_wrapper.h

@@ -128,6 +128,11 @@ DENG2_PUBLIC Info* Info_NewFromFile(const char* nativePath);
 DENG2_PUBLIC void Info_Delete(Info* info);
 DENG2_PUBLIC int Info_FindValue(Info* info, const char* path, char* buffer, size_t bufSize);
 
+/*
+ * UnixInfo
+ */
+DENG2_PUBLIC int UnixInfo_GetConfigValue(const char* configFile, const char* key, char* dest, size_t destLen);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif

doomsday/libdeng2/include/de/core/app.h

@@ -26,6 +26,7 @@
 #include "../FS"
 #include "../Module"
 #include "../Config"
+#include "../UnixInfo"
 #include <QApplication>
 
 /**
@@ -94,6 +95,11 @@ namespace de
          */
         static Config& config();
 
+        /**
+         * Returns the Unix system-level configuration preferences.
+         */
+        static UnixInfo& unixInfo();
+
         /**
          * Imports a script module that is located on the import path.
          *
@@ -118,6 +124,8 @@ namespace de
         /// The file system.
         FS _fs;
 
+        UnixInfo _unixInfo;
+
         /// The configuration.
         Config* _config;
 

doomsday/libdeng2/include/de/core/unixinfo.h

@@ -0,0 +1,64 @@
+/**
+ * @file unixinfo.h
+ * Unix system-level configuration. @ingroup core
+ *
+ * @authors Copyright © 2012 Jaakko Keränen <jaakko.keranen@iki.fi>
+ * @authors Copyright © 2012 Daniel Swanson <danij@dengine.net>
+ *
+ * @par License
+ * GPL: http://www.gnu.org/licenses/gpl.html
+ *
+ * <small>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 2 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, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA</small>
+ */
+
+#ifndef LIBDENG2_UNIXINFO_H
+#define LIBDENG2_UNIXINFO_H
+
+#include "../String"
+
+namespace de {
+
+/**
+ * System-level configuration preferences for the Unix platform. These are used
+ * for setting specific directory locations, e.g., where shared libraries are
+ * expected to be found. The configuration has two levels: system-global
+ * configuration under <tt>/etc</tt> and user-specific configuration under
+ * <tt>~/.doomsday</tt>.
+ */
+class UnixInfo
+{
+public:
+    /**
+     * Loads the system-level Info files.
+     */
+    UnixInfo();
+
+    ~UnixInfo();
+
+    /**
+     * Returns a path preference.
+     *
+     * @param key    Path identifier.
+     * @param value  The value is returned here.
+     *
+     * @return  Path.
+     */
+    bool path(const String& key, String& value) const;
+
+private:
+    struct Instance;
+    Instance* d;
+};
+
+} // namespace de
+
+#endif // LIBDENG2_UNIXINFO_H

doomsday/libdeng2/include/de/data/info.h

@@ -193,6 +193,14 @@ class Info
 
 public:
     Info();
+
+    /**
+     * Parses a string of text as Info source.
+     *
+     * @param source  Info source text.
+     */
+    Info(const String& source);
+
     ~Info();
 
     /**
@@ -202,10 +210,28 @@ class Info
      */
     void parse(const String& infoSource);
 
+    /**
+     * Parses the Info contents from a native text file.
+     *
+     * @param nativePath  Path of a native file containing the Info source.
+     */
+    void parseNativeFile(const String& nativePath);
+
     const BlockElement& root() const;
 
     const Element* findByPath(const String& path) const;
 
+    /**
+     * Finds the value of a key.
+     *
+     * @param key    Key to find.
+     * @param value  The value is returned here.
+     *
+     * @return @c true, if the key was found and @a value is valid. If @c
+     * false, the key was not found and @a value is not changed.
+     */
+    bool findValueForKey(const String& key, String& value) const;
+
 private:
     struct Instance;
     Instance* d;

doomsday/libdeng2/libdeng2.pro

@@ -61,6 +61,7 @@ HEADERS += \
     include/de/Library \
     include/de/Log \
     include/de/LogBuffer \
+    include/de/UnixInfo \
     include/de/Vector
 
 HEADERS += \
@@ -75,7 +76,8 @@ HEADERS += \
     include/de/core/commandline.h \
     include/de/core/library.h \
     include/de/core/log.h \
-    include/de/core/logbuffer.h
+    include/de/core/logbuffer.h \
+    include/de/core/unixinfo.h
 
 # Private headers.
 HEADERS += \
@@ -90,7 +92,8 @@ SOURCES += \
     src/core/callbacktimer.cpp \
     src/core/library.cpp \
     src/core/log.cpp \
-    src/core/logbuffer.cpp
+    src/core/logbuffer.cpp \
+    src/core/unixinfo.cpp
 
 OTHER_FILES += \
     config/deng.de

doomsday/libdeng2/src/c_wrapper.cpp

@@ -18,6 +18,8 @@
  */
 
 #include "de/c_wrapper.h"
+#include "de/Error"
+#include "de/App"
 #include "de/LegacyCore"
 #include "de/LegacyNetwork"
 #include "de/Address"
@@ -344,25 +346,28 @@ Info* Info_NewFromString(const char* utf8text)
 {
     try
     {
-        QScopedPointer<de::Info> self(new de::Info);
-        self->parse(QString::fromUtf8(utf8text));
-        return reinterpret_cast<Info*>(self.take());
+        return reinterpret_cast<Info*>(new de::Info(QString::fromUtf8(utf8text)));
     }
-    catch(de::Error& er)
+    catch(const de::Error& er)
     {
         LOG_WARNING(er.asText());
+        return 0;
     }
-    return 0;
 }
 
 Info* Info_NewFromFile(const char* nativePath)
 {
-    QFile file(nativePath);
-    if(file.open(QFile::ReadOnly | QFile::Text))
+    try
+    {
+        QScopedPointer<de::Info> info(new de::Info);
+        info->parseNativeFile(QString::fromUtf8(nativePath));
+        return reinterpret_cast<Info*>(info.take());
+    }
+    catch(const de::Error& er)
     {
-        return Info_NewFromString(file.readAll().constData());
+        LOG_WARNING(er.asText());
+        return 0;
     }
-    return 0;
 }
 
 void Info_Delete(Info* info)
@@ -393,3 +398,17 @@ int Info_FindValue(Info* info, const char* path, char* buffer, size_t bufSize)
         return value.size();
     }
 }
+
+int UnixInfo_GetConfigValue(const char* configFile, const char* key, char* dest, size_t destLen)
+{
+    // "paths" is the only config file currently being used.
+    if(qstrcmp(configFile, "paths")) return false;
+
+    de::String foundValue;
+    if(de::App::unixInfo().path(key, foundValue))
+    {
+        qstrncpy(dest, foundValue.toUtf8().constData(), destLen);
+        return true;
+    }
+    return false;
+}

doomsday/libdeng2/src/core/app.cpp

@@ -157,27 +157,32 @@ String App::executablePath()
     return DENG2_APP->_appPath;
 }
 
-FS &App::fileSystem()
+FS& App::fileSystem()
 {
     return DENG2_APP->_fs;
 }
 
-Folder &App::fileRoot()
+Folder& App::fileRoot()
 {
     return fileSystem().root();
 }
 
-Folder &App::homeFolder()
+Folder& App::homeFolder()
 {
     return fileRoot().locate<Folder>("/home");
 }
 
-Config &App::config()
+Config& App::config()
 {
     DENG2_ASSERT(DENG2_APP->_config != 0);
     return *DENG2_APP->_config;
 }
 
+UnixInfo& App::unixInfo()
+{
+    return DENG2_APP->_unixInfo;
+}
+
 static int sortFilesByModifiedAt(const File* a, const File* b)
 {
     return cmp(a->status().modifiedAt, b->status().modifiedAt);