function _db_mangle_query(&$databases, $qstruct)
{
global $SCHEMA;
global $SYNTAX_QUERY;
if ($list = @$qstruct["UNION"]) {
foreach ($list as $alias => $subq) {
$qstruct[$alias] = _db_mangle_query($databases, $subq);
}
return $qstruct;
}
if ($error = db_check_syntax($qstruct, $SYNTAX_QUERY)) {
echo "qstruct error: {$error}<br>\n";
global $debug;
if ($debug) {
echo "syntax: ";
print_r($qstruct);
echo "<br>\n";
}
return null;
}
// make a homogenous array syntax out of comma-separated strings
$h**o = _db_homogenize($qstruct);
$h**o = _db_add_schema($h**o);
$h**o = _db_mangle_joins($h**o);
// check whether all tables are on the same database
foreach ($h**o["BASE_TABLE"] as $table) {
$database = _db_database($table);
$databases[$database] = true;
}
if (count($databases) > 1) {
die("NYI: connot treat queries spanning multiple databases\n");
}
return $h**o;
}
function _mysql_make_boolean($table, $field, $value, $use_or)
{
global $RAW_DOTID;
global $ERROR;
global $debug;
// check nested conditions
if (!is_string($field) && is_array($value)) {
// toggle and<->or
$subres = _mysql_make_where($table, $value, !$use_or);
return "({$subres})";
}
// check unary operators
$regex = "/^\\s*?(exists|not(?:\\s+exists)?)\\s*\$/";
if (preg_match($regex, $field, $matches)) {
$op = $matches[1];
if (preg_match("/exists/", $op)) {
$dummy = array();
$subres = mysql_make_query($dummy, $value);
} else {
$subres = _mysql_make_where($table, $value, $use_or);
}
return "{$op} ({$subres})";
}
// check binary operators
$op = "=";
$regex = "/^(\\\\?{$RAW_DOTID})?\\s*(?:(=|<>|<|>|<=|>=|!|@|%| like| rlike| in| not in)\\s*({$RAW_DOTID})?)?\$/";
$old_field = $field;
if (!preg_match($regex, $field, $matches)) {
$ERROR = "bad field expression '{$field}'";
return "/*bad field expression '{$field}'*/false";
}
$field = $matches[1];
if (!$field) {
// pure operator
if (!@$matches[2]) {
die("bad single operator");
}
$op = trim($matches[2]);
$arg1 = $value[0];
$arg2 = $value[1];
$value1 = _db_homogenize($arg1);
$value2 = _db_homogenize($arg2);
$dummy = array();
$subquery1 = mysql_make_query($dummy, $value1);
$dummy = array();
$subquery2 = mysql_make_query($dummy, $value2);
$res = "({$subquery1}) {$op} ({$subquery2})";
return $res;
}
$realfield = _db_realname($table, $field);
if (!$realfield) {
die("cannot find field '{$field}' in table '{$table}'\n");
}
$sql_value = null;
if (@$matches[3]) {
$sql_value = $matches[3];
$op = trim($matches[2]);
} elseif (is_null($value)) {
$op = "!";
} else {
if (@$matches[2]) {
$op = trim($matches[2]);
if (is_array($value) && !@$value["TABLE"] && !@$value["UNION"]) {
// multiple conditions (indicated by absence of TABLE or UNION)
$res = "";
foreach ($value as $item) {
if ($res) {
if ($use_or) {
$res .= " or ";
} else {
$res .= " and ";
}
}
// treat the same as if the operator had been repeated.
$res .= _mysql_make_boolean($table, $old_field, $item, $use_or);
}
return $res;
}
}
if (is_array($value)) {
// sub-sql statement (indicated by _absence_ of operator)
if (!@$value["TABLE"] && !@$value["UNION"]) {
// test against most sloppiness
print_r($value);
die("field '{$old_field}': badly formed sub-sql statement\n");
}
if ($debug) {
echo "start homogenizing: ";
print_r($value);
echo "<br>\n";
}
$value = _db_homogenize($value);
$dummy = array();
$subquery = mysql_make_query($dummy, $value);
$sql_value = "({$subquery})";
} else {
$sql_value = db_esc_sql($value);
}
}
if ($op == "@") {
$res = "{$realfield} is not null";
} elseif ($op == "%" || $op == "like") {
$res = "{$realfield} like {$sql_value}";
} elseif ($op == "!") {
$res = "{$realfield} is null";
} else {
$res = "{$realfield} {$op} {$sql_value}";
}
return $res;
}