refactor: rm run_process_utility_hook from internal module

Partly addresses #79

The `handle_alter_extension` and `handle_drop_extension` were using
`run_process_utility_hook` various times unnecessarily.

Now this operation is only executed once on each statement case.

Author: steve-chavez

src/privileged_extensions.c

@@ -248,56 +248,24 @@ void handle_create_extension(
     pfree(filename);
 }
 
-void handle_alter_extension(
-    void (*process_utility_hook)(PROCESS_UTILITY_PARAMS),
-    PROCESS_UTILITY_PARAMS,
-    const char *extname, const char *privileged_extensions,
-    const char *superuser) {
-
-    if (is_string_in_comma_delimited_string(extname,
-                                            privileged_extensions)) {
-        bool already_switched_to_superuser = false;
-        switch_to_superuser(superuser,
-                            &already_switched_to_superuser);
-
-        run_process_utility_hook(process_utility_hook);
+bool all_extensions_are_privileged(List *objects, const char *privileged_extensions){
+  ListCell *lc;
 
-        if (!already_switched_to_superuser) {
-            switch_to_original_role();
-        }
-    } else {
-        run_process_utility_hook(process_utility_hook);
-    }
-}
+  if(privileged_extensions == NULL) return false;
 
-void handle_drop_extension(void (*process_utility_hook)(PROCESS_UTILITY_PARAMS),
-                           PROCESS_UTILITY_PARAMS,
-                           const char *privileged_extensions,
-                           const char *superuser) {
-    DropStmt *stmt = (DropStmt *)pstmt->utilityStmt;
-    bool all_extensions_are_privileged = true;
-    ListCell *lc;
+  foreach (lc, objects) {
+      char *name = strVal(lfirst(lc));
 
-    foreach (lc, stmt->objects) {
-        char *name = strVal(lfirst(lc));
+      if (!is_string_in_comma_delimited_string(name, privileged_extensions)) {
+          return false;
+      }
+  }
 
-        if (!is_string_in_comma_delimited_string(name, privileged_extensions)) {
-            all_extensions_are_privileged = false;
-            break;
-        }
-    }
-
-    if (all_extensions_are_privileged) {
-        bool already_switched_to_superuser = false;
-        switch_to_superuser(superuser,
-                            &already_switched_to_superuser);
+  return true;
+}
 
-        run_process_utility_hook(process_utility_hook);
+bool is_extension_privileged(const char *extname, const char *privileged_extensions){
+  if(privileged_extensions == NULL) return false;
 
-        if (!already_switched_to_superuser) {
-            switch_to_original_role();
-        }
-    } else {
-        run_process_utility_hook(process_utility_hook);
-    }
+  return is_string_in_comma_delimited_string(extname, privileged_extensions);
 }

src/privileged_extensions.h

@@ -11,16 +11,8 @@ extern void handle_create_extension(
     const char *privileged_extensions_custom_scripts_path,
     const extension_parameter_overrides *epos, const size_t total_epos);
 
-extern void
-handle_alter_extension(void (*process_utility_hook)(PROCESS_UTILITY_PARAMS),
-                       PROCESS_UTILITY_PARAMS,
-                       const char *extname,
-                       const char *privileged_extensions,
-                       const char *superuser);
+bool all_extensions_are_privileged(List *objects, const char *privileged_extensions);
 
-extern void
-handle_drop_extension(void (*process_utility_hook)(PROCESS_UTILITY_PARAMS),
-                      PROCESS_UTILITY_PARAMS, const char *privileged_extensions,
-                      const char *superuser);
+bool is_extension_privileged(const char *extname, const char *privileged_extensions);
 
 #endif

src/supautils.c

@@ -464,39 +464,45 @@ static void supautils_hook(PROCESS_UTILITY_PARAMS) {
       if (superuser()) {
           break;
       }
-      if (privileged_extensions == NULL) {
-          break;
-      }
 
       AlterExtensionStmt *stmt = (AlterExtensionStmt *)pstmt->utilityStmt;
 
-      handle_alter_extension(prev_hook,
-                             PROCESS_UTILITY_ARGS,
-                             stmt->extname,
-                             privileged_extensions,
-                             supautils_superuser);
-      return;
+      if (is_extension_privileged(stmt->extname, privileged_extensions)) {
+          bool already_switched_to_superuser = false;
+
+          switch_to_superuser(supautils_superuser, &already_switched_to_superuser);
+
+          run_process_utility_hook(prev_hook);
+
+          if (!already_switched_to_superuser) {
+              switch_to_original_role();
+          }
+      }
+
+      break;
   }
 
   /*
    * ALTER EXTENSION <extension> SET SCHEMA
    */
   case T_AlterObjectSchemaStmt: {
+      if (superuser()) {
+          break;
+      }
+
       AlterObjectSchemaStmt *stmt = (AlterObjectSchemaStmt *)pstmt->utilityStmt;
 
-      if (stmt->objectType == OBJECT_EXTENSION){
-          if (superuser()) {
-              break;
-          }
-          if (privileged_extensions == NULL) {
-              break;
-          }
+      if (stmt->objectType == OBJECT_EXTENSION &&
+          is_extension_privileged(strVal(stmt->object), privileged_extensions)) {
+         bool already_switched_to_superuser = false;
+
+         switch_to_superuser(supautils_superuser, &already_switched_to_superuser);
+
+         run_process_utility_hook(prev_hook);
 
-          handle_alter_extension(prev_hook,
-                                 PROCESS_UTILITY_ARGS,
-                                 strVal(stmt->object),
-                                 privileged_extensions,
-                                 supautils_superuser);
+         if (!already_switched_to_superuser) {
+             switch_to_original_role();
+         }
 
          return;
       }
@@ -666,14 +672,21 @@ static void supautils_hook(PROCESS_UTILITY_PARAMS) {
            */
           case OBJECT_EXTENSION:
           {
-              if (privileged_extensions == NULL) {
-                  break;
+              if (all_extensions_are_privileged(stmt->objects, privileged_extensions)) {
+                bool already_switched_to_superuser = false;
+                switch_to_superuser(supautils_superuser,
+                                    &already_switched_to_superuser);
+
+                run_process_utility_hook(prev_hook);
+
+                if (!already_switched_to_superuser) {
+                    switch_to_original_role();
+                }
+
+                return;
               }
-              handle_drop_extension(prev_hook,
-                                    PROCESS_UTILITY_ARGS,
-                                    privileged_extensions,
-                                    supautils_superuser);
-              return;
+
+              break;
           }
 
           /*