Reverted a previous change where we removed env var and registry checks

mariadb_windows.py

@@ -16,16 +16,46 @@ class MariaDBConfiguration():
 
 
 def get_config(options):
-    required_version = "3.1.0"
-
     static= options["link_static"];
     mariadb_dir= options["install_dir"]
+    required_version= "3.1.5"
 
+    if not os.path.exists(mariadb_dir):
+      try:
+          mariadb_dir= os.environ["MARIADB_CC_INSTALL_DIR"]
+          cc_version = ["", ""]
+          cc_instdir = [mariadb_dir, ""]
+          print("using environment configuration " + mariadb_dir)
+      except KeyError:
+
+          try:
+              local_reg = ConnectRegistry(None, HKEY_LOCAL_MACHINE)
+              if platform.architecture()[0] == '32bit':
+                  connector_key = OpenKey(local_reg,
+                                          'SOFTWARE\\MariaDB Corporation\\MariaDB Connector C')
+              else:
+                  connector_key = OpenKey(local_reg,
+                                          'SOFTWARE\\MariaDB Corporation\\MariaDB Connector C 64-bit',
+                                          access=KEY_READ | KEY_WOW64_64KEY)
+              cc_version = QueryValueEx(connector_key, "Version")
+              if cc_version[0] < required_version:
+                  print("MariaDB Connector/Python requires MariaDB Connector/C >= %s (found version: %s") \
+                       % (required_version, cc_version[0])
+                  sys.exit(2)
+              mariadb_dir = QueryValueEx(connector_key, "InstallDir")
+
+          except:
+              print("Could not find InstallationDir of MariaDB Connector/C. "
+                    "Please make sure MariaDB Connector/C is installed or specify the InstallationDir of "
+                    "MariaDB Connector/C by setting the environment variable MARIADB_CC_INSTALL_DIR.")
+              sys.exit(3)
+
+    print("Found MariaDB Connector/C in '%s'" % mariadb_dir[0])
     cfg = MariaDBConfiguration()
-    cfg.includes = [".\\include", options["install_dir"] + "\\include", options["install_dir"] + "\\include\\mysql"]
+    cfg.includes = [".\\include", mariadb_dir[0] + "\\include", mariadb_dir[0] + "\\include\\mysql"]
-    cfg.lib_dirs = [options["install_dir"] + "\\lib"]
+    cfg.lib_dirs = [mariadb_dir[0] + "\\lib"]
     cfg.libs = ["ws2_32", "advapi32", "kernel32", "shlwapi", "crypt32"]
-    if static:
+    if static.lower() == "on":
         cfg.libs.append("mariadbclient")
     else:
         cfg.libs.append("libmariadb")