Bug 794916 - Fails to find environment file at startup when installation prefix is '/opt'

Update on this bug. Before doing the binreloc dance on various
paths check if the calculated dynamic prefix is still the same
as the compile time PREFIX. If so, just stick with the compile
time path names as this means the application wasn't relocated
anyway. Only if the dynamic prefix is different, try to
recalculate the requested paths relative to the dynamic
prefix.
Together with the configure time fix to detect /etc/opt is
outside of the /opt prefix, this eliminates the need for further
special case handling of the sysconfig directory so that
special case handling is removed.

libgnucash/core-utils/binreloc.c

@@ -459,7 +459,10 @@ gnc_gbr_find_prefix (const gchar *default_prefix)
  *
  * If compiled_dir exists and is an absolute path then we check the dynamic
  * prefix and if it's NULL fall back first on the passed-in default and then on
- * compiled_dir; otherwise we pass the compiled PREFIX value as a default to
+ * compiled_dir;
+ * otherwise if the dynamic prefix turns out to be the compile time defined PREFIX
+ * just use that
+ * otherwise we pass the compiled PREFIX value as a default to
  * gnc_gbr_find_prefix, remove the PREFIX part (if any) from the compiled_dir
  * and append that to the retrieved prefix.
  */
@@ -471,6 +474,9 @@ find_component_directory (const gchar *default_dir, const gchar* compiled_dir)
     prefix = gnc_gbr_find_prefix (NULL);
     if (prefix == NULL)
         return g_strdup (default_dir ? default_dir : compiled_dir);
+    else if (!g_strcmp0 (prefix, PREFIX))
+        return g_strdup (compiled_dir);
+
     subdir = gnc_file_path_relative_part(PREFIX, compiled_dir);
     if (g_strcmp0 (compiled_dir, subdir) == 0)
     {
@@ -544,7 +550,6 @@ gchar *
 gnc_gbr_find_lib_dir (const gchar *default_lib_dir)
 {
     return find_component_directory (default_lib_dir, LIBDIR);
-
 }
 
 /** Locate the application's configuration files folder.
@@ -563,62 +568,7 @@ gnc_gbr_find_lib_dir (const gchar *default_lib_dir)
 gchar *
 gnc_gbr_find_etc_dir (const gchar *default_etc_dir)
 {
-    gchar *prefix, *dir, *sysconfdir;
-
-    prefix = gnc_gbr_find_prefix (NULL);
-    if (prefix == NULL)
-    {
-        /* BinReloc not initialized. */
-        if (default_etc_dir != NULL)
-            return g_strdup (default_etc_dir);
-        else
-            return NULL;
-    }
-
-    if (g_path_is_absolute (SYSCONFDIR))
-    {
-        sysconfdir = gnc_file_path_relative_part (PREFIX, SYSCONFDIR);
-        if (g_strcmp0 (sysconfdir, SYSCONFDIR) == 0)
-        {
-            g_free (sysconfdir);
-            sysconfdir = gnc_file_path_relative_part("/", SYSCONFDIR);
-        }
-        dir = g_build_filename (prefix, sysconfdir, NULL);
-        g_free (sysconfdir);
-    }
-    else if ((g_strcmp0 (PREFIX, "/opt") == 0) ||
-             (g_str_has_prefix (PREFIX, "/opt/")))
-    {
-        /* If the prefix is "/opt/..." the etc stuff will be installed in
-         * "SYSCONFDIR/opt/...", while the rest will be in "/opt/..."
-         * If this gets relocated after (make install), there will be another
-         * prefix prepended to all of that:
-         * "prefix2/opt/..."
-         * "prefix2/SYSCONFDIR/opt/..."
-         * Note: this most likely won't work on Windows. Don't try a /opt
-         * prefix on that platform...
-         */
-        gchar *std_etc_dir = g_build_filename ("/", SYSCONFDIR, PREFIX, NULL);
-
-        gchar *base_prefix_pos = g_strstr_len (prefix, -1, PREFIX);
-        if (!base_prefix_pos || base_prefix_pos == prefix)
-            dir = g_build_filename ("/", std_etc_dir, NULL);
-        else
-        {
-            gchar *prefix2 = g_strndup (prefix, base_prefix_pos - prefix);
-            dir = g_build_filename (prefix2, std_etc_dir, NULL);
-        }
-        g_free (std_etc_dir);
-
-    }
-    else
-    {
-        sysconfdir = gnc_file_path_relative_part(PREFIX, SYSCONFDIR);
-        dir = g_build_filename (prefix, sysconfdir, NULL);
-        g_free (sysconfdir);
-    }
-    g_free (prefix);
-    return dir;
+    return find_component_directory (default_etc_dir, SYSCONFDIR);
 }