Allow to set INKSCAPE_DATADIR via environment variable

INKSCAPE_DATADIR is the prefix prepended to all resource paths
(i.e. typically /share or similar on Linux system)
and typically set at compile time with the INKSCAPE_DATADIR define
(unless configured with ENABLE_BINRELOC)

This commit allows to override this default on Windows and Linux
(compiled without ENABLE_BINRELOC) by setting the environment
variable INKSCAPE_DATADIR.

5 files changed, 128 insertions, 100 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 4c56b211d..c6ef78a4f 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -233,6 +233,7 @@ set(inkscape_SRC
   object-set.cpp
   object-snapper.cpp
   path-chemistry.cpp
+  path-prefix.cpp
   persp3d-reference.cpp
   persp3d.cpp
   perspective-line.cpp
diff --git a/src/path-prefix.cpp b/src/path-prefix.cpp
new file mode 100644
index 000000000..87b756eb4
--- /dev/null
+++ b/src/path-prefix.cpp
@@ -0,0 +1,74 @@
+/*
+ * path-prefix.cpp - Inkscape specific prefix handling
+ *
+ * Authors:
+ *   Eduard Braun <eduard.braun2@gmx.de>
+ *
+ * Copyright (C) 2017 Authors
+ *
+ * This file is part of Inkscape.
+ *
+ * Inkscape 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.
+ *
+ * See the file COPYING for details.
+ *
+ */
+
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+
+#include <glib.h>
+#include "path-prefix.h"
+
+
+/**
+ * Determine the location of the Inkscape data directory (typically the share/ folder
+ * from where Inkscape should be loading resources) and append a relative path
+ *
+ *  - by default use the compile time value of INKSCAPE_DATADIR
+ *  - on Windows inkscape_datadir will be relative to the called executable by default
+ *    (typically inkscape/share but also handles the case where the executable is in a /bin subfolder)
+ *  - if the environment variable INKSCAPE_DATADIR is set it will override all of the above
+ */
+char *append_inkscape_datadir(const char *relative_path)
+{
+    static gchar const *inkscape_datadir;
+    if (!inkscape_datadir) {
+        gchar const *datadir_env = g_getenv("INKSCAPE_DATADIR");
+        if (datadir_env) {
+            inkscape_datadir = g_strdup(datadir_env);
+        } else {
+#ifdef _WIN32
+            gchar *module_path = g_win32_get_package_installation_directory_of_module(NULL);
+            inkscape_datadir = g_build_filename(module_path, "share", NULL);
+            g_free(module_path);
+#else
+            inkscape_datadir = INKSCAPE_DATADIR;
+#endif
+        }
+    }
+
+    if (!relative_path) {
+        relative_path = "";
+    }
+
+    return g_build_filename(inkscape_datadir, relative_path, NULL);
+}
+
+
+/*
+  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 :
diff --git a/src/path-prefix.h b/src/path-prefix.h
index d6514d832..b69ad3753 100644
--- a/src/path-prefix.h
+++ b/src/path-prefix.h
@@ -18,9 +18,13 @@
 #endif
 #include "prefix.h"
 
-//#ifdef __cplusplus
-//extern "C" {
-//#endif /* __cplusplus */
+
+char *append_inkscape_datadir(const char *relative_path);
+
+#ifdef _WIN32
+#undef INKSCAPE_DATADIR
+#define INKSCAPE_DATADIR append_inkscape_datadir(NULL)
+#endif
 
 #ifdef ENABLE_BINRELOC
 /* The way that we're building now is with a shared library between Inkscape
@@ -52,30 +56,30 @@
 #    define CREATE_PALETTESDIR    BR_DATADIR( INKSCAPE_LIBPREFIX "/share/create/swatches" )
 #    define CREATE_PATTERNSDIR    BR_DATADIR( INKSCAPE_LIBPREFIX "/share/create/patterns/vector" )
 #else
-#  ifdef WIN32
-#    define INKSCAPE_APPICONDIR   WIN32_DATADIR("pixmaps")
-#    define INKSCAPE_ATTRRELDIR   WIN32_DATADIR("attributes")
-#    define INKSCAPE_BINDDIR      WIN32_DATADIR("bind")
-#    define INKSCAPE_EXAMPLESDIR  WIN32_DATADIR("examples")
-#    define INKSCAPE_EXTENSIONDIR WIN32_DATADIR("extensions")
-#    define INKSCAPE_FILTERDIR    WIN32_DATADIR("filters")
-#    define INKSCAPE_FONTSDIR     WIN32_DATADIR("fonts")
-#    define INKSCAPE_GRADIENTSDIR WIN32_DATADIR("gradients")
-#    define INKSCAPE_KEYSDIR      WIN32_DATADIR("keys")
-#    define INKSCAPE_PIXMAPDIR    WIN32_DATADIR("icons")
-#    define INKSCAPE_MARKERSDIR   WIN32_DATADIR("markers")
-#    define INKSCAPE_PALETTESDIR  WIN32_DATADIR("palettes")
-#    define INKSCAPE_PATTERNSDIR  WIN32_DATADIR("patterns")
-#    define INKSCAPE_SCREENSDIR   WIN32_DATADIR("screens")
-#    define INKSCAPE_SYMBOLSDIR   WIN32_DATADIR("symbols")
-#    define INKSCAPE_THEMEDIR     INKSCAPE_PIXMAPDIR
-#    define INKSCAPE_TUTORIALSDIR WIN32_DATADIR("tutorials")
-#    define INKSCAPE_TEMPLATESDIR WIN32_DATADIR("templates")
-#    define INKSCAPE_UIDIR        WIN32_DATADIR("ui")
+#  ifdef _WIN32
+#    define INKSCAPE_APPICONDIR   append_inkscape_datadir("pixmaps")
+#    define INKSCAPE_ATTRRELDIR   append_inkscape_datadir("attributes")
+#    define INKSCAPE_BINDDIR      append_inkscape_datadir("bind")
+#    define INKSCAPE_EXAMPLESDIR  append_inkscape_datadir("examples")
+#    define INKSCAPE_EXTENSIONDIR append_inkscape_datadir("extensions")
+#    define INKSCAPE_FILTERDIR    append_inkscape_datadir("filters")
+#    define INKSCAPE_FONTSDIR     append_inkscape_datadir("fonts")
+#    define INKSCAPE_GRADIENTSDIR append_inkscape_datadir("gradients")
+#    define INKSCAPE_KEYSDIR      append_inkscape_datadir("keys")
+#    define INKSCAPE_PIXMAPDIR    append_inkscape_datadir("icons")
+#    define INKSCAPE_MARKERSDIR   append_inkscape_datadir("markers")
+#    define INKSCAPE_PALETTESDIR  append_inkscape_datadir("palettes")
+#    define INKSCAPE_PATTERNSDIR  append_inkscape_datadir("patterns")
+#    define INKSCAPE_SCREENSDIR   append_inkscape_datadir("screens")
+#    define INKSCAPE_SYMBOLSDIR   append_inkscape_datadir("symbols")
+#    define INKSCAPE_THEMEDIR     append_inkscape_datadir("icons")
+#    define INKSCAPE_TUTORIALSDIR append_inkscape_datadir("tutorials")
+#    define INKSCAPE_TEMPLATESDIR append_inkscape_datadir("templates")
+#    define INKSCAPE_UIDIR        append_inkscape_datadir("ui")
 //CREATE V0.1  WIN32 support
-#    define CREATE_GRADIENTSDIR   WIN32_DATADIR("create\\gradients\\gimp")
-#    define CREATE_PALETTESDIR    WIN32_DATADIR("create\\swatches")
-#    define CREATE_PATTERNSDIR    WIN32_DATADIR("create\\patterns\\vector")
+#    define CREATE_GRADIENTSDIR   append_inkscape_datadir("create\\gradients\\gimp")
+#    define CREATE_PALETTESDIR    append_inkscape_datadir("create\\swatches")
+#    define CREATE_PATTERNSDIR    append_inkscape_datadir("create\\patterns\\vector")
 #  elif defined ENABLE_OSX_APP_LOCATIONS
 #    define INKSCAPE_APPICONDIR   "Contents/Resources/share/pixmaps"
 #    define INKSCAPE_ATTRRELDIR   "Contents/Resources/share/inkscape/attributes"
@@ -101,34 +105,30 @@
 #    define CREATE_PALETTESDIR   "/Library/Application Support/create/swatches"
 #    define CREATE_PATTERNSDIR   "/Library/Application Support/create/patterns/vector"
 #  else
-#    define INKSCAPE_APPICONDIR   INKSCAPE_DATADIR "/pixmaps"
-#    define INKSCAPE_ATTRRELDIR   INKSCAPE_DATADIR "/inkscape/attributes"
-#    define INKSCAPE_BINDDIR      INKSCAPE_DATADIR "/inkscape/bind"
-#    define INKSCAPE_EXAMPLESDIR  INKSCAPE_DATADIR "/inkscape/examples"
-#    define INKSCAPE_EXTENSIONDIR INKSCAPE_DATADIR "/inkscape/extensions"
-#    define INKSCAPE_FILTERDIR    INKSCAPE_DATADIR "/inkscape/filters"
-#    define INKSCAPE_FONTSDIR     INKSCAPE_DATADIR "/inkscape/fonts"
-#    define INKSCAPE_GRADIENTSDIR INKSCAPE_DATADIR "/inkscape/gradients"
-#    define INKSCAPE_KEYSDIR      INKSCAPE_DATADIR "/inkscape/keys"
-#    define INKSCAPE_PIXMAPDIR    INKSCAPE_DATADIR "/inkscape/icons"
-#    define INKSCAPE_MARKERSDIR   INKSCAPE_DATADIR "/inkscape/markers"
-#    define INKSCAPE_PALETTESDIR  INKSCAPE_DATADIR "/inkscape/palettes"
-#    define INKSCAPE_PATTERNSDIR  INKSCAPE_DATADIR "/inkscape/patterns"
-#    define INKSCAPE_SCREENSDIR   INKSCAPE_DATADIR "/inkscape/screens"
-#    define INKSCAPE_SYMBOLSDIR   INKSCAPE_DATADIR "/inkscape/symbols"
-#    define INKSCAPE_THEMEDIR     INKSCAPE_DATADIR "/icons"
-#    define INKSCAPE_TUTORIALSDIR INKSCAPE_DATADIR "/inkscape/tutorials"
-#    define INKSCAPE_TEMPLATESDIR INKSCAPE_DATADIR "/inkscape/templates"
-#    define INKSCAPE_UIDIR        INKSCAPE_DATADIR "/inkscape/ui"
+#    define INKSCAPE_APPICONDIR   append_inkscape_datadir("pixmaps")
+#    define INKSCAPE_ATTRRELDIR   append_inkscape_datadir("inkscape/attributes")
+#    define INKSCAPE_BINDDIR      append_inkscape_datadir("inkscape/bind")
+#    define INKSCAPE_EXAMPLESDIR  append_inkscape_datadir("inkscape/examples")
+#    define INKSCAPE_EXTENSIONDIR append_inkscape_datadir("inkscape/extensions")
+#    define INKSCAPE_FILTERDIR    append_inkscape_datadir("inkscape/filters")
+#    define INKSCAPE_FONTSDIR     append_inkscape_datadir("inkscape/fonts")
+#    define INKSCAPE_GRADIENTSDIR append_inkscape_datadir("inkscape/gradients")
+#    define INKSCAPE_KEYSDIR      append_inkscape_datadir("inkscape/keys")
+#    define INKSCAPE_PIXMAPDIR    append_inkscape_datadir("inkscape/icons")
+#    define INKSCAPE_MARKERSDIR   append_inkscape_datadir("inkscape/markers")
+#    define INKSCAPE_PALETTESDIR  append_inkscape_datadir("inkscape/palettes")
+#    define INKSCAPE_PATTERNSDIR  append_inkscape_datadir("inkscape/patterns")
+#    define INKSCAPE_SCREENSDIR   append_inkscape_datadir("inkscape/screens")
+#    define INKSCAPE_SYMBOLSDIR   append_inkscape_datadir("inkscape/symbols")
+#    define INKSCAPE_THEMEDIR     append_inkscape_datadir("icons")
+#    define INKSCAPE_TUTORIALSDIR append_inkscape_datadir("inkscape/tutorials")
+#    define INKSCAPE_TEMPLATESDIR append_inkscape_datadir("inkscape/templates")
+#    define INKSCAPE_UIDIR        append_inkscape_datadir("inkscape/ui")
 //CREATE V0.1 support
-#    define CREATE_GRADIENTSDIR INKSCAPE_DATADIR "/create/gradients/gimp"
-#    define CREATE_PALETTESDIR  INKSCAPE_DATADIR "/create/swatches"
-#    define CREATE_PATTERNSDIR  INKSCAPE_DATADIR "/create/patterns/vector"
-#	 endif
+#    define CREATE_GRADIENTSDIR   append_inkscape_datadir("create/gradients/gimp")
+#    define CREATE_PALETTESDIR    append_inkscape_datadir("create/swatches")
+#    define CREATE_PATTERNSDIR    append_inkscape_datadir("create/patterns/vector")
+#  endif
 #endif
 
-//#ifdef __cplusplus
-//}
-//#endif /* __cplusplus */
-
 #endif /* _PATH_PREFIX_H_ */
diff --git a/src/prefix.cpp b/src/prefix.cpp
index c8bf7abec..14fdd04df 100644
--- a/src/prefix.cpp
+++ b/src/prefix.cpp
@@ -416,44 +416,4 @@ br_extract_prefix (const char *path)
 }
 #endif /* __cplusplus */
 
-
-
-#ifdef __WIN32__
-/**
- * Provide a similar mechanism for Win32.  Enable a macro,
- * WIN32_DATADIR, that can look up subpaths for inkscape resources 
- */
-
-/**
- * Get the Windows-equivalent of INKSCAPE_DATADIR and append a relative path
- *
- *  - by default INKSCAPE_DATADIR will be relative to the called executable
- *    (typically inkscape/share but also handles the case where the executable is in a /bin subfolder)
- *  - to override set the INKSCAPE_DATADIR environment variable
- */
-char *win32_append_datadir(const char *relative_path)
-{
-    static gchar *datadir;
-    if (!datadir) {
-        gchar const *inkscape_datadir = g_getenv("INKSCAPE_DATADIR");
-        if (inkscape_datadir) {
-            datadir = g_strdup(inkscape_datadir);
-        } else {
-            gchar *module_path = g_win32_get_package_installation_directory_of_module(NULL);
-            datadir = g_build_filename(module_path, "share", NULL);
-            g_free(module_path);
-        }
-    }
-
-    if (!relative_path) {
-        relative_path = "";
-    }
-
-    return g_build_filename(datadir, relative_path, NULL);
-}
-#endif /* __WIN32__ */
-
-
-
-
 #endif /* _PREFIX_C */
diff --git a/src/prefix.h b/src/prefix.h
index d28e896d0..bdf3b6df4 100644
--- a/src/prefix.h
+++ b/src/prefix.h
@@ -118,11 +118,4 @@ char *br_extract_prefix(const char *path);
 }
 #endif /* __cplusplus */
 
-#ifdef __WIN32__
-char *win32_append_datadir(const char *relative_path);
-#undef INKSCAPE_DATADIR
-#define INKSCAPE_DATADIR win32_append_datadir(NULL)
-#define WIN32_DATADIR(suffix) (win32_append_datadir(suffix))
-#endif
-
 #endif /* _PREFIX_H_ */