Source/WebCore/platform/sql/SQLiteStatement.h

/*
 * Copyright (C) 2006-2021 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 * 1. Redistributions of source code must retain the above copyright
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 *    documentation and/or other materials provided with the distribution.
 *
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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#pragma once

#include "SQLValue.h"
#include "SQLiteDatabase.h"
#include <wtf/Span.h>

struct sqlite3_stmt;

namespace WebCore {

class SQLiteStatement {
    WTF_MAKE_NONCOPYABLE(SQLiteStatement); WTF_MAKE_FAST_ALLOCATED;
public:
    WEBCORE_EXPORT ~SQLiteStatement();
    WEBCORE_EXPORT SQLiteStatement(SQLiteStatement&&);
    
    WEBCORE_EXPORT int bindBlob(int index, Span<const uint8_t>);
    WEBCORE_EXPORT int bindBlob(int index, const String&);
    WEBCORE_EXPORT int bindText(int index, StringView);
    WEBCORE_EXPORT int bindInt(int index, int);
    WEBCORE_EXPORT int bindInt64(int index, int64_t);
    WEBCORE_EXPORT int bindDouble(int index, double);
    WEBCORE_EXPORT int bindNull(int index);
    WEBCORE_EXPORT int bindValue(int index, const SQLValue&);
    WEBCORE_EXPORT unsigned bindParameterCount() const;

    WEBCORE_EXPORT int step();
    WEBCORE_EXPORT int reset();
    
    // steps and finalizes the query.
    // returns true if all 3 steps succeed with step() returning SQLITE_DONE
    // returns false otherwise  
    WEBCORE_EXPORT bool executeCommand();

    // Returns -1 on last-step failing.  Otherwise, returns number of rows
    // returned in the last step()
    int columnCount();

    bool isReadOnly();
    
    WEBCORE_EXPORT bool isColumnDeclaredAsBlob(int col);
    String columnName(int col);
    SQLValue columnValue(int col);
    WEBCORE_EXPORT String columnText(int col);
    WEBCORE_EXPORT double columnDouble(int col);
    WEBCORE_EXPORT int columnInt(int col);
    WEBCORE_EXPORT int64_t columnInt64(int col);
    WEBCORE_EXPORT String columnBlobAsString(int col);
    WEBCORE_EXPORT Vector<uint8_t> columnBlob(int col);

    // The returned Span stays valid until the next step() / reset() or destruction of the statement.
    Span<const uint8_t> columnBlobAsSpan(int col);

    SQLiteDatabase& database() { return m_database; }
    
private:
    friend class SQLiteDatabase;
    SQLiteStatement(SQLiteDatabase&, sqlite3_stmt*);

    // Returns true if the prepared statement has been stepped at least once using step() but has neither run to completion (returned SQLITE_DONE from step()) nor been reset().
    bool hasStartedStepping();

    SQLiteDatabase& m_database;
    sqlite3_stmt* m_statement;
};

} // namespace WebCore