Add inscape to search path

This primarily allows extensions to simply call "inkscape"
without requiring the user to modify environment variables or
worrying about different versions of inkscape on the same machine
(as we prefix the search path).

We did this already for Windows but the code was removed in
  db05b842cba28f01b431eee890537959aa2d8fe3

Partially fixes https://gitlab.com/inkscape/inkscape/issues/115

1 files changed, 65 insertions, 0 deletions

diff --git a/src/path-prefix.cpp b/src/path-prefix.cpp
index eefe7ff39..a2b7c9fbc 100644
--- a/src/path-prefix.cpp
+++ b/src/path-prefix.cpp
@@ -12,6 +12,14 @@
 # include "config.h"  // only include where actually required!
 #endif
 
+#ifdef _WIN32
+#include <windows.h> // for GetModuleFileNameW
+#endif
+
+#ifdef __APPLE__
+#include <mach-o/dyld.h> // for _NSGetExecutablePath
+#endif
+
 #include "io/resource.h"
 #include "path-prefix.h"
 #include <glib.h>
@@ -115,6 +123,63 @@ gchar *get_datadir_path()
 
     return datadir;
 }
+
+/**
+ * Gets the the currently running program's executable name (including full path)
+ *
+ * @return executable name (including full path) encoded as UTF-8
+ *         or NULL if it can't be determined
+ */
+gchar *get_program_name()
+{
+    static gchar *program_name = NULL;
+
+    if (program_name == NULL) {
+        // There is no portable way to get an executable's name including path, so we need to do it manually.
+        // TODO: Re-evaluate boost::dll::program_location() once we require Boost >= 1.61
+        //
+        // The following platform-specific code is partially based on GdxPixbuf's get_toplevel()
+        // See also https://stackoverflow.com/a/1024937
+#if defined(_WIN32)
+        wchar_t module_file_name[MAX_PATH];
+        if (GetModuleFileNameW(NULL, module_file_name, MAX_PATH)) {
+            program_name = g_utf16_to_utf8((gunichar2 *)module_file_name, -1, NULL, NULL, NULL);
+        } else {
+            g_warning("get_program_name() - GetModuleFileNameW failed");
+        }
+#elif defined(__APPLE__)
+        char pathbuf[PATH_MAX + 1];
+        uint32_t bufsize = sizeof(pathbuf);
+        if (_NSGetExecutablePath(pathbuf, &bufsize) == 0) {
+            program_name = g_strdup(pathbuf);
+        } else {
+            g_warning("get_program_name() - _NSGetExecutablePath failed");
+        }
+#elif defined(__linux__)
+        program_name = g_file_read_link("/proc/self/exe", NULL);
+        if (!program_name) {
+            g_warning("get_program_name() - g_file_read_link failed");
+        }
+#else
+#warning get_program_name() - no known way to obtain executable name on this platform
+        g_info("get_program_name() - no known way to obtain executable name on this platform");
+#endif
+    }
+
+    return program_name;
+}
+
+/**
+ * Gets the the full path to the directory containing the currently running program's executable
+ *
+ * @return full path to directory encoded as UTF-8
+ *         or NULL if it can't be determined
+ */
+gchar *get_program_dir()
+{
+    return g_path_get_dirname(get_program_name());
+}
+
 /*
   Local Variables:
   mode:c++