python · berkerpeksag · Apr 14, 2021 · Feb 22, 2021 · Feb 28, 2021 · Feb 22, 2021
diff --git a/Lib/sqlite3/test/userfunctions.py b/Lib/sqlite3/test/userfunctions.py
@@ -276,6 +276,10 @@ def test_any_arguments(self):
        val = cur.fetchone()[0]
        self.assertEqual(val, 2)

+    def test_empty_blob(self):
+        cur = self.con.execute("select isblob(x'')")
+        self.assertTrue(cur.fetchone()[0])
+
    # Regarding deterministic functions:
    #
    # Between 3.8.3 and 3.15.0, deterministic functions were only used to

diff --git a/Misc/NEWS.d/next/Library/2021-03-01-13-01-33.bpo-43296.p_gU6T.rst b/Misc/NEWS.d/next/Library/2021-03-01-13-01-33.bpo-43296.p_gU6T.rst
@@ -0,0 +1,3 @@
+Improve :mod:`sqlite3` error handling: ``sqlite3_value_blob()`` errors that
+set ``SQLITE_NOMEM`` now raise :exc:`MemoryError`. Patch by Erlend E.
+Aasland.
diff --git a/Modules/_sqlite/connection.c b/Modules/_sqlite/connection.c
@@ -546,7 +546,6 @@ _pysqlite_build_py_params(sqlite3_context *context, int argc,
    sqlite3_value* cur_value;
    PyObject* cur_py_value;
    const char* val_str;
-    Py_ssize_t buflen;

    args = PyTuple_New(argc);
    if (!args) {
@@ -571,26 +570,37 @@ _pysqlite_build_py_params(sqlite3_context *context, int argc,
                    cur_py_value = Py_NewRef(Py_None);
                }
                break;
-            case SQLITE_BLOB:
-                buflen = sqlite3_value_bytes(cur_value);
-                cur_py_value = PyBytes_FromStringAndSize(
-                    sqlite3_value_blob(cur_value), buflen);
+            case SQLITE_BLOB: {
+                sqlite3 *db = sqlite3_context_db_handle(context);
+                const void *blob = sqlite3_value_blob(cur_value);
+
+                if (blob == NULL && sqlite3_errcode(db) == SQLITE_NOMEM) {
+                    PyErr_NoMemory();
+                    goto error;
+                }
+
+                Py_ssize_t size = sqlite3_value_bytes(cur_value);
+                cur_py_value = PyBytes_FromStringAndSize(blob, size);
                break;
+            }
            case SQLITE_NULL:
            default:
                cur_py_value = Py_NewRef(Py_None);
        }

        if (!cur_py_value) {
-            Py_DECREF(args);
-            return NULL;
+            goto error;
        }

        PyTuple_SetItem(args, i, cur_py_value);

    }

    return args;
+
+error:
+    Py_DECREF(args);
+    return NULL;
 }

 static void
-Original file line number
+Diff line change
@@ -546,7 +546,6 @@ _pysqlite_build_py_params(sqlite3_context *context, int argc,
         sqlite3_value* cur_value;
         PyObject* cur_py_value;
         const char* val_str;
-        Py_ssize_t buflen;
         args = PyTuple_New(argc);
         if (!args) {
@@ -571,26 +570,37 @@ _pysqlite_build_py_params(sqlite3_context *context, int argc,
                         cur_py_value = Py_NewRef(Py_None);
                     }
                     break;
-                case SQLITE_BLOB:
-                    buflen = sqlite3_value_bytes(cur_value);
-                    cur_py_value = PyBytes_FromStringAndSize(
-                        sqlite3_value_blob(cur_value), buflen);
+                case SQLITE_BLOB: {
+                    sqlite3 *db = sqlite3_context_db_handle(context);
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            berkerpeksag
  

      

      

      


        Apr 14, 2021



      
    

  

  
    
      
          
    
  


        
            
  
      
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      Maybe it may make sense to see what other core devs think about declaring new variables inside case.
    
  
  



    

        
      
  
  
    
  
  
  
    
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            erlend-aasland
  

      

      

      


        Apr 14, 2021



      
    

  

  
    
      
          
    
  


        
            
  
      
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      Well, there's plenty of other such cases in the code base: grep -A1 -rE "\<case\>.*:.*{" Modules
    
  
  



    

        
      
  
  
    
  
  
  
    
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+                    const void *blob = sqlite3_value_blob(cur_value);
+                    if (blob == NULL && sqlite3_errcode(db) == SQLITE_NOMEM) {
+                        PyErr_NoMemory();
+                        goto error;
+                    }
+                    Py_ssize_t size = sqlite3_value_bytes(cur_value);
+                    cur_py_value = PyBytes_FromStringAndSize(blob, size);
                     break;
+                }
                 case SQLITE_NULL:
                 default:
                     cur_py_value = Py_NewRef(Py_None);
             }
             if (!cur_py_value) {
-                Py_DECREF(args);
-                return NULL;
+                goto error;
             }
             PyTuple_SetItem(args, i, cur_py_value);
         }
         return args;
+    error:
+        Py_DECREF(args);
+        return NULL;
     }
     static void
-          Expand Down