mysql.cpp

Shorthand是一个强大的脚本语言

    {
    }

    virtual int
        spi_ClearParameters(ShhCursorHandle hCursor)
    {
        return 0;
    }

    virtual int
        spi_PasteValue(ShhCursorHandle hCursor, ShhDbExecutor* executor, int index, string& out, const char* value)
    {
        const char* p = value;
        out.append('\'');
        while(*p) 
        {
            if (strchr("\'\"\\", *p)) out.append('\\');
            else if (*p == '\n') { out.append("\\n"); p++; continue; }
            else if (*p == '\r') { out.append("\\r"); p++; continue; }
            out.append(*p);
            p++;
        }
        out.append('\'');
        return 0;
    }

    virtual int
        spi_BindValue(ShhCursorHandle hCursor, ShhDbExecutor* executor, int index, const char* value)
    {
        return 0;
    }

};

/*
ShhRecordSet::~ShhRecordSet()
{
    if (m_result != NULL)
        mysql_free_result(m_result);
}
 

bool ShhSQL::hasMethod(const char* method)
{
    if (stricmp(method, "EXECUTE") == 0)
        return true;
    else
        return false;
}


void ShhSQL::paste_value(string& out, ShhValue value)
{
    switch (value.m_type)
    {
    case SHH_INT:    out.appendf("%d", value.toInt()); return;
    case SHH_FLOAT:  out.appendf("%.15g", value.toFloat()); return;
    case SHH_DATE:   
        {
            string s; datetime dt; value.toDate(dt);
            dt.export_common(s);
            out.appendf("'%s'", s.cstr());
            return;
        }
    case SHH_STRING:
        {
            string s; value.toString(s);
            const char* p = s;
            out.append('\'');
            while(*p) 
            {
                if (strchr("\'\"\\", *p)) out.append('\\');
                else if (*p == '\n') { out.append("\\n"); p++; continue; }
                else if (*p == '\r') { out.append("\\r"); p++; continue; }
                out.append(*p);
                p++;
            }
            out.append('\'');
            return;
        }
    
    case SHH_OBJECT:
        {
            const char* type = (value.m_value.u_object != NULL) ? 
                value.m_value.u_object->getTypeName() : "NULL";
            throw new ShhObjectException(2803, "Object <%s> cannot be inserted into SQL. Use explicit conversion");
        }

    default:
        throw new ShhObjectException(2801, "Value of unknown type cannot be pasted into SQL");
    }
}

void ShhSQL::substitute(ShhValueList* args, const char* sqlin, string &sqlout)
{
    int argind = 0;
    int argc = args ? args->size() : 0;

    const char* in = sqlin;
    
    char quote = '\0';
    char comment = '\0';
    
    sqlout.clear();
    
    while(*in)
    {
        if (quote != '\0')
        {
            if (*in == '\\') { sqlout.append(*in); in++; }
            else if (*in == quote) quote = '\0';
        }
        else if (*in == '\'' || *in == '\"')
        {
            quote = *in;
        }
        else if (*in == '?')
        {
            if (args == NULL || argind >= argc)
                throw new ShhObjectException(2800, "this SQL requires at least %d parameter(s) - %d passed", argind+1, argc);
            
            paste_value(sqlout, *(args->get(argind)));
            in++;
            argind++;
            continue;
        }
        else if (*in == ':')
        {
            string name; in++;
            while(*in && (isalnum(*in) || *in == '_')) name.append(*in++);
            
            ShhVariable* var = m_module.findVariable(name);
            if (var == NULL)
                throw new ShhObjectException(2804, "variable '%s' for SQL substitution is not found", name.cstr());
            
            paste_value(sqlout, var->value());
            continue;
        }
        sqlout.append(*in);    
        in++;
    }

}


ShhValue ShhSQL::execute(ShhValueList* args)
{
    MYSQL* session = provide_session();

    string sqlin, sqlout;

    getProperty("STATEMENT").toString(sqlin);
    if (sqlin.is_empty())
        throw new ShhObjectException("SQL statement is not defined for object");
    
    substitute(args, sqlin, sqlout);

    if (mysql_query(session, sqlout) != 0)
    {
        int code = mysql_errno(session);
        const char* msg = mysql_error(session);
	throwSQL("SQL Query failed: MySQL error %d: %s", code, msg);
    }
    return ShhValue::null();

}


ShhValue ShhRecordSet::execute(ShhValueList* args)
{
    ShhSQL::execute(args);

    // release previous result in case of multiple executions
    if (m_result != NULL) { mysql_free_result(m_result); m_result = NULL; }

    m_result = mysql_store_result(m_connection->m_session);
    if (m_result == NULL)
    {
        m_field_count = 0;
        m_total_row_count = 0;
        m_row_num = 0;
    } 
    else
    {
        m_field_count = mysql_num_fields(m_result);
        m_total_row_count = (int) mysql_num_rows(m_result);
        m_row_num = 1;
    }

    return ShhValue::null();
}

ShhValue ShhRecordSet::method_more()
{
    if (m_row_num < 0)
    {
        return ShhValue::null();
    }

    return ShhValue(m_row_num < m_total_row_count);
}

ShhValue ShhRecordSet::method_count()
{
    if (m_result == NULL)
       throw new ShhObjectException(2807, "Recordset was not executed", mysql_error(m_connection->m_session));

    return ShhValue(m_total_row_count);
}

ShhValue ShhRecordSet::method_finished()
{
    return ShhValue(m_row_num <= 0);
}


ShhValue ShhRecordSet::method_next()
{
    MYSQL* session = provide_session();
    m_changed_since_execute = true;

    ShhValue zero(0);

    if (m_result == NULL)
       throw new ShhObjectException(2806, "Recordset was not executed", mysql_error(session));

    MYSQL_ROW row = mysql_fetch_row(m_result);
    if (row == NULL)
    {
        m_row_num = -1;
        if (mysql_errno(session) != 0)
            throw new ShhObjectException("fetch failed: %s", mysql_error(session));
        else
        {
            return zero;
        }
    }

    if (m_field_count == 0) 
    {
        m_row_num = 0;
        return zero;
    }

    unsigned long* lengths = mysql_fetch_lengths(m_result);
    MYSQL_FIELD* fields = mysql_fetch_fields(m_result);

    for(int i=0,n=m_field_count; i<n; i++)
    {
        MYSQL_FIELD* field = &fields[i];
        const char* name = field->name;
        unsigned int length = lengths[i];
        ShhValue value("");
        if (length > 0)
        {
            char* data = (char*) m_module.scratch().malloc(length+1);
            memcpy(data, row[i], length);
            data[length] = '\0';
            value.m_value.u_string = data;
            value.m_type = SHH_STRING;
        }
        setProperty(name, value);
    }

    m_row_num++;

    return ShhValue(1);

}



ShhValue ShhRecordSet::method_rownum()
{
    MYSQL* session = provide_session();
    return ShhValue(m_row_num);
}

ShhValue ShhRecordSet::method_value(ShhValueList* args)
{
    if (args == NULL || args->size() < 1)
    {
        throw new ShhObjectException("method VALUE() needs argument (field name)");
    }
    
    string name; args->get(0)->toString(name);

    MYSQL* session = provide_session();
    return getProperty(name);
}
*/

ShhDbDriver* create_mysql_driver()
{
    return new MySQLDriver();
}