From bc0205c6583cea1faf1370850e0c3c83dfd2f366 Mon Sep 17 00:00:00 2001 From: optimistex Date: Wed, 19 Oct 2016 23:45:10 +0300 Subject: [PATCH] fix file names --- Expression.lib.php | 584 ++++++++++++++++++++++++++++++++++++++++++++ Expression.php | 586 +-------------------------------------------- ExpressionCore.php | 18 -- composer.json | 4 +- 4 files changed, 596 insertions(+), 596 deletions(-) create mode 100644 Expression.lib.php delete mode 100644 ExpressionCore.php diff --git a/Expression.lib.php b/Expression.lib.php new file mode 100644 index 0000000..cc440d3 --- /dev/null +++ b/Expression.lib.php @@ -0,0 +1,584 @@ + +Copyright (C) 2016 Jakub Jankiewicz + +================================================================================ + +NAME + Expression - safely evaluate math and boolean expressions + +SYNOPSIS + evaluate('2+2'); + // supports: order of operation; parentheses; negation; built-in functions + $result = $e->evaluate('-8(5/2)^2*(1-sqrt(4))-8'); + // create your own variables + $e->evaluate('a = e^(ln(pi))'); + // or functions + $e->evaluate('f(x,y) = x^2 + y^2 - 2x*y + 1'); + // and then use them + $result = $e->evaluate('3*f(42,a)'); + ?> + +DESCRIPTION + Use the Expressoion class when you want to evaluate mathematical or boolean + expressions from untrusted sources. You can define your own variables and + functions, which are stored in the object. Try it, it's fun! + + Based on http://www.phpclasses.org/browse/file/11680.html, cred to Miles Kaufmann + +METHODS + $e->evalute($expr) + Evaluates the expression and returns the result. If an error occurs, + prints a warning and returns false. If $expr is a function assignment, + returns true on success. + + $e->e($expr) + A synonym for $e->evaluate(). + + $e->vars() + Returns an associative array of all user-defined variables and values. + + $e->funcs() + Returns an array of all user-defined functions. + +PARAMETERS + $e->suppress_errors + Set to true to turn off warnings when evaluating expressions + + $e->last_error + If the last evaluation failed, contains a string describing the error. + (Useful when suppress_errors is on). + +AUTHORS INFORMATION + Copyright 2005, Miles Kaufmann. + Copyright 2016, Jakub Jankiewicz + +LICENSE + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + 1 Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + 3. The name of the author may not be used to endorse or promote + products derived from this software without specific prior written + permission. + + THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, + INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + POSSIBILITY OF SUCH DAMAGE. + +*/ + +class Expression +{ + + var $suppress_errors = false; + var $last_error = null; + + var $v = array('e' => 2.71, 'pi' => 3.14); // variables (and constants) + var $f = array(); // user-defined functions + var $vb = array('e', 'pi'); // constants + var $fb = array( // built-in functions + 'sin', 'sinh', 'arcsin', 'asin', 'arcsinh', 'asinh', + 'cos', 'cosh', 'arccos', 'acos', 'arccosh', 'acosh', + 'tan', 'tanh', 'arctan', 'atan', 'arctanh', 'atanh', + 'sqrt', 'abs', 'ln', 'log'); + + var $functions = array(); // function defined outside of Expression as closures + + function __construct() + { + // make the variables a little more accurate + $this->v['pi'] = pi(); + $this->v['e'] = exp(1); + } + + function e($expr) + { + return $this->evaluate($expr); + } + + function evaluate($expr) + { + $this->last_error = null; + $expr = trim($expr); + if (substr($expr, -1, 1) == ';') $expr = substr($expr, 0, strlen($expr) - 1); // strip semicolons at the end + //=============== + // is it a variable assignment? + if (preg_match('/^\s*([a-z]\w*)\s*=(?!~|=)\s*(.+)$/', $expr, $matches)) { + if (in_array($matches[1], $this->vb)) { // make sure we're not assigning to a constant + return $this->trigger("cannot assign to constant '$matches[1]'"); + } + $tmp = $this->pfx($this->nfx($matches[2])); + $this->v[$matches[1]] = $tmp; // if so, stick it in the variable array + return $this->v[$matches[1]]; // and return the resulting value + //=============== + // is it a function assignment? + } elseif (preg_match('/^\s*([a-z]\w*)\s*\((?:\s*([a-z]\w*(?:\s*,\s*[a-z]\w*)*)\s*)?\)\s*=(?!~|=)\s*(.+)$/', $expr, $matches)) { + $fnn = $matches[1]; // get the function name + if (in_array($matches[1], $this->fb)) { // make sure it isn't built in + return $this->trigger("cannot redefine built-in function '$matches[1]()'"); + } + + if ($matches[2] != "") { + $args = explode(",", preg_replace("/\s+/", "", $matches[2])); // get the arguments + } else { + $args = array(); + } + if (($stack = $this->nfx($matches[3])) === false) return false; // see if it can be converted to postfix + for ($i = 0; $i < count($stack); $i++) { // freeze the state of the non-argument variables + $token = $stack[$i]; + if (preg_match('/^[a-z]\w*$/', $token) and !in_array($token, $args)) { + if (array_key_exists($token, $this->v)) { + $stack[$i] = $this->v[$token]; + } else { + return $this->trigger("undefined variable '$token' in function definition"); + } + } + } + $this->f[$fnn] = array('args' => $args, 'func' => $stack); + return true; + //=============== + } else { + return $this->pfx($this->nfx($expr)); // straight up evaluation, woo + } + } + + function vars() + { + $output = $this->v; + unset($output['pi']); + unset($output['e']); + return $output; + } + + function funcs() + { + $output = array(); + foreach ($this->f as $fnn => $dat) + $output[] = $fnn . '(' . implode(',', $dat['args']) . ')'; + return $output; + } + + //===================== HERE BE INTERNAL METHODS ====================\\ + + // Convert infix to postfix notation + function nfx($expr) + { + $index = 0; + $stack = new ExpressionStack; + $output = array(); // postfix form of expression, to be passed to pfx() + $expr = trim(strtolower($expr)); + + $ops = array('+', '-', '*', '/', '^', '_', '%', '>', '<', '>=', '<=', '==', '!=', '=~', '&&', '||', '!'); + $ops_r = array('+' => 0, '-' => 0, '*' => 0, '/' => 0, '%' => 0, '^' => 1, '>' => 0, + '<' => 0, '>=' => 0, '<=' => 0, '==' => 0, '!=' => 0, '=~' => 0, + '&&' => 0, '||' => 0, '!' => 0); // right-associative operator? + $ops_p = array('+' => 4, '-' => 4, '*' => 4, '/' => 4, '_' => 4, '%' => 4, '^' => 5, '>' => 2, '<' => 2, + '>=' => 2, '<=' => 2, '==' => 2, '!=' => 2, '=~' => 2, '&&' => 1, '||' => 1, '!' => 5); // operator precedence + + $expecting_op = false; // we use this in syntax-checking the expression + // and determining when a - is a negation + + /* we allow all characters because of strings + if (preg_match("%[^\w\s+*^\/()\.,-<>=&~|!\"\\\\/]%", $expr, $matches)) { // make sure the characters are all good + return $this->trigger("illegal character '{$matches[0]}'"); + } + */ + $first_argument = false; + while (1) { // 1 Infinite Loop ;) + $op = substr($expr, $index, 2); // get the first two characters at the current index + if (preg_match("/^[+\-*\/^_\"<>=%(){\[!~,](?!=|~)/", $op) || preg_match("/\w/", $op)) { + // fix $op if it should have one character + $op = substr($expr, $index, 1); + } + $single_str = '(?"(?:[^"]|\\\\")*"|[^[{\]}]|(?1))*[\]}]'; + $number = '[\d.]+e\d+|\d+(?:\.\d*)?|\.\d+'; + $name = '[a-z]\w*\(?|\\$\w+'; + $parenthesis = '\\('; + // find out if we're currently at the beginning of a number/string/object/array/variable/function/parenthesis/operand + $ex = preg_match("%^($single_str|$double_str|$json|$name|$number|$parenthesis)%", substr($expr, $index), $match); + //=============== + if ($op == '[' && $expecting_op && $ex) { + if (!preg_match("/^\[(.*)\]$/", $match[1], $matches)) { + return $this->trigger("invalid array access"); + } + $stack->push('['); + $stack->push($matches[1]); + $index += strlen($match[1]); + //} elseif ($op == '!' && !$expecting_op) { + // $stack->push('!'); // put a negation on the stack + // $index++; + } elseif ($op == '-' and !$expecting_op) { // is it a negation instead of a minus? + $stack->push('_'); // put a negation on the stack + $index++; + } elseif ($op == '_') { // we have to explicitly deny this, because it's legal on the stack + return $this->trigger("illegal character '_'"); // but not in the input expression + //=============== + } elseif (((in_array($op, $ops) or $ex) and $expecting_op) or in_array($op, $ops) and !$expecting_op) { + // are we putting an operator on the stack? + if ($ex) { // are we expecting an operator but have a number/variable/function/opening parethesis? + $op = '*'; + $index--; // it's an implicit multiplication + } + // heart of the algorithm: + while ($stack->count > 0 and ($o2 = $stack->last()) and in_array($o2, $ops) and ($ops_r[$op] ? $ops_p[$op] < $ops_p[$o2] : $ops_p[$op] <= $ops_p[$o2])) { + $output[] = $stack->pop(); // pop stuff off the stack into the output + + } + // many thanks: http://en.wikipedia.org/wiki/Reverse_Polish_notation#The_algorithm_in_detail + $stack->push($op); // finally put OUR operator onto the stack + $index++; + if (strlen($op) == 2) { + $index++; + } + $expecting_op = false; + //=============== + } elseif ($op == ')' and $expecting_op || !$ex) { // ready to close a parenthesis? + while (($o2 = $stack->pop()) != '(') { // pop off the stack back to the last ( + if (is_null($o2)) return $this->trigger("unexpected ')'"); + else $output[] = $o2; + } + if (preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) { // did we just close a function? + $fnn = $matches[1]; // get the function name + $arg_count = $stack->pop(); // see how many arguments there were (cleverly stored on the stack, thank you) + $output[] = $stack->pop(); // pop the function and push onto the output + if (in_array($fnn, $this->fb)) { // check the argument count + if ($arg_count > 1) + return $this->trigger("too many arguments ($arg_count given, 1 expected)"); + } elseif (array_key_exists($fnn, $this->f)) { + if ($arg_count != count($this->f[$fnn]['args'])) + return $this->trigger("wrong number of arguments ($arg_count given, " . count($this->f[$fnn]['args']) . " expected) " . json_encode($this->f[$fnn]['args'])); + } elseif (array_key_exists($fnn, $this->functions)) { + $func_reflection = new ReflectionFunction($this->functions[$fnn]); + $count = $func_reflection->getNumberOfParameters(); + if ($arg_count != $count) + return $this->trigger("wrong number of arguments ($arg_count given, " . $count . " expected)"); + } else { // did we somehow push a non-function on the stack? this should never happen + return $this->trigger("internal error"); + } + } + $index++; + //=============== + } elseif ($op == ',' and $expecting_op) { // did we just finish a function argument? + + while (($o2 = $stack->pop()) != '(') { + if (is_null($o2)) return $this->trigger("unexpected ','"); // oops, never had a ( + else $output[] = $o2; // pop the argument expression stuff and push onto the output + } + // make sure there was a function + if (!preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) + return $this->trigger("unexpected ','"); + if ($first_argument) { + $first_argument = false; + } else { + $stack->push($stack->pop() + 1); // increment the argument count + } + $stack->push('('); // put the ( back on, we'll need to pop back to it again + $index++; + $expecting_op = false; + //=============== + } elseif ($op == '(' and !$expecting_op) { + $stack->push('('); // that was easy + $index++; +// $allow_neg = true; + //=============== + } elseif ($ex and !$expecting_op) { // do we now have a function/variable/number? + $expecting_op = true; + $val = $match[1]; + if ($op == '[' || $op == "{" || preg_match("/null|true|false/", $match[1])) { + $output[] = $val; + } elseif (preg_match("/^([a-z]\w*)\($/", $val, $matches)) { // may be func, or variable w/ implicit multiplication against parentheses... + if (in_array($matches[1], $this->fb) or + array_key_exists($matches[1], $this->f) or + array_key_exists($matches[1], $this->functions) + ) { // it's a func + $stack->push($val); + $stack->push(0); + $stack->push('('); + $expecting_op = false; + } else { // it's a var w/ implicit multiplication + $val = $matches[1]; + $output[] = $val; + } + } else { // it's a plain old var or num + $output[] = $val; + if (preg_match("/^([a-z]\w*)\($/", $stack->last(3))) { + $first_argument = true; + while (($o2 = $stack->pop()) != '(') { + if (is_null($o2)) return $this->trigger("unexpected error"); // oops, never had a ( + else $output[] = $o2; // pop the argument expression stuff and push onto the output + } + // make sure there was a function + if (!preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) + return $this->trigger("unexpected error"); + + $stack->push($stack->pop() + 1); // increment the argument count + $stack->push('('); // put the ( back on, we'll need to pop back to it again + } + } + $index += strlen($val); + //=============== + } elseif ($op == ')') { // miscellaneous error checking + return $this->trigger("unexpected ')'"); + } elseif (in_array($op, $ops) and !$expecting_op) { + return $this->trigger("unexpected operator '$op'"); + } else { // I don't even want to know what you did to get here + return $this->trigger("an unexpected error occured " . json_encode($op) . " " . json_encode($match) . " " . ($ex ? 'true' : 'false') . " " . $expr); + } + if ($index == strlen($expr)) { + if (in_array($op, $ops)) { // did we end with an operator? bad. + return $this->trigger("operator '$op' lacks operand"); + } else { + break; + } + } + while (substr($expr, $index, 1) == ' ') { // step the index past whitespace (pretty much turns whitespace + $index++; // into implicit multiplication if no operator is there) + } + + } + while (!is_null($op = $stack->pop())) { // pop everything off the stack and push onto output + if ($op == '(') return $this->trigger("expecting ')'"); // if there are (s on the stack, ()s were unbalanced + $output[] = $op; + } + return $output; + } + + // evaluate postfix notation + function pfx($tokens, $vars = array()) + { + + if ($tokens == false) return false; + $stack = new ExpressionStack(); + foreach ($tokens as $token) { // nice and easy + // if the token is a binary operator, pop two values off the stack, do the operation, and push the result back on + if (in_array($token, array('+', '-', '*', '/', '^', '<', '>', '<=', '>=', '==', '&&', '||', '!=', '=~', '%'))) { + $op2 = $stack->pop(); + $op1 = $stack->pop(); + switch ($token) { + case '+': + if (is_string($op1) || is_string($op2)) { + $stack->push((string)$op1 . (string)$op2); + } else { + $stack->push($op1 + $op2); + } + break; + case '-': + $stack->push($op1 - $op2); + break; + case '*': + $stack->push($op1 * $op2); + break; + case '/': + if ($op2 == 0) return $this->trigger("division by zero"); + $stack->push($op1 / $op2); + break; + case '%': + $stack->push($op1 % $op2); + break; + case '^': + $stack->push(pow($op1, $op2)); + break; + case '>': + $stack->push($op1 > $op2); + break; + case '<': + $stack->push($op1 < $op2); + break; + case '>=': + $stack->push($op1 >= $op2); + break; + case '<=': + $stack->push($op1 <= $op2); + break; + case '==': + if (is_array($op1) && is_array($op2)) { + $stack->push(json_encode($op1) == json_encode($op2)); + } else { + $stack->push($op1 == $op2); + } + break; + case '!=': + if (is_array($op1) && is_array($op2)) { + $stack->push(json_encode($op1) != json_encode($op2)); + } else { + $stack->push($op1 != $op2); + } + break; + case '=~': + $value = @preg_match($op2, $op1, $match); + + if (!is_int($value)) { + return $this->trigger("Invalid regex " . json_encode($op2)); + } + $stack->push($value); + for ($i = 0; $i < count($match); $i++) { + $this->v['$' . $i] = $match[$i]; + } + break; + case '&&': + $stack->push($op1 ? $op2 : $op1); + break; + case '||': + $stack->push($op1 ? $op1 : $op2); + break; + } + // if the token is a unary operator, pop one value off the stack, do the operation, and push it back on + } elseif ($token == '!') { + $stack->push(!$stack->pop()); + } elseif ($token == '[') { + $selector = $stack->pop(); + $object = $stack->pop(); + if (is_object($object)) { + $stack->push($object->$selector); + } elseif (is_array($object)) { + $stack->push($object[$selector]); + } else { + return $this->trigger("invalid object for selector"); + } + } elseif ($token == "_") { + $stack->push(-1 * $stack->pop()); + // if the token is a function, pop arguments off the stack, hand them to the function, and push the result back on + } elseif (preg_match("/^([a-z]\w*)\($/", $token, $matches)) { // it's a function! + $fnn = $matches[1]; + if (in_array($fnn, $this->fb)) { // built-in function: + if (is_null($op1 = $stack->pop())) return $this->trigger("internal error"); + $fnn = preg_replace("/^arc/", "a", $fnn); // for the 'arc' trig synonyms + if ($fnn == 'ln') $fnn = 'log'; + $stack->push($fnn($op1)); // perfectly safe variable function call + } elseif (array_key_exists($fnn, $this->f)) { // user function + // get args + $args = []; + for ($i = count($this->f[$fnn]['args']) - 1; $i >= 0; $i--) { + if ($stack->isEmpty()) { + return $this->trigger("internal error " . $fnn . " " . json_encode($this->f[$fnn]['args'])); + } + $args[$this->f[$fnn]['args'][$i]] = $stack->pop(); + } + $stack->push($this->pfx($this->f[$fnn]['func'], $args)); // yay... recursion!!!! + } else if (array_key_exists($fnn, $this->functions)) { + $reflection = new ReflectionFunction($this->functions[$fnn]); + $count = $reflection->getNumberOfParameters(); + $args = []; + for ($i = $count - 1; $i >= 0; $i--) { + if ($stack->isEmpty()) { + return $this->trigger("internal error"); + } + $args[] = $stack->pop(); + } + $stack->push($reflection->invokeArgs($args)); + } + // if the token is a number or variable, push it on the stack + } else { + if (preg_match('/^([\[{](?>"(?:[^"]|\\")*"|[^[{\]}]|(?1))*[\]}])$/', $token) || + preg_match("/^(null|true|false)$/", $token) + ) { // json + //return $this->trigger("invalid json " . $token); + if ($token == 'null') { + $value = null; + } elseif ($token == 'true') { + $value = true; + } elseif ($token == 'false') { + $value = false; + } else { + $value = json_decode($token); + if ($value == null) { + return $this->trigger("invalid json " . $token); + } + } + $stack->push($value); + } elseif (is_numeric($token)) { + $stack->push(0 + $token); + } else if (preg_match("/^['\\\"](.*)['\\\"]$/", $token)) { + $stack->push(json_decode(preg_replace_callback("/^['\\\"](.*)['\\\"]$/", function ($matches) { + $m = array("/\\\\'/", '/(?v)) { + $stack->push($this->v[$token]); + } elseif (array_key_exists($token, $vars)) { + $stack->push($vars[$token]); + } else { + return $this->trigger("undefined variable '$token'"); + } + } + } + // when we're out of tokens, the stack should have a single element, the final result + if ($stack->count != 1) return $this->trigger("internal error"); + return $stack->pop(); + } + + /** + * trigger an error, but nicely, if need be + * @param string $msg + * @return bool + */ + function trigger($msg) + { + $this->last_error = $msg; + if (!$this->suppress_errors) trigger_error($msg, E_USER_WARNING); + return false; + } +} + +/** + * for internal use + */ +class ExpressionStack +{ + var $stack = array(); + var $count = 0; + + function push($val) + { + $this->stack[$this->count] = $val; + $this->count++; + } + + function pop() + { + if ($this->count > 0) { + $this->count--; + return $this->stack[$this->count]; + } + return null; + } + + function isEmpty() + { + return empty($this->stack); + } + + function last($n = 1) + { + if (isset($this->stack[$this->count - $n])) { + return $this->stack[$this->count - $n]; + } + return null; + } +} \ No newline at end of file diff --git a/Expression.php b/Expression.php index cc440d3..b6740bb 100644 --- a/Expression.php +++ b/Expression.php @@ -1,584 +1,18 @@ -Copyright (C) 2016 Jakub Jankiewicz - -================================================================================ - -NAME - Expression - safely evaluate math and boolean expressions - -SYNOPSIS - evaluate('2+2'); - // supports: order of operation; parentheses; negation; built-in functions - $result = $e->evaluate('-8(5/2)^2*(1-sqrt(4))-8'); - // create your own variables - $e->evaluate('a = e^(ln(pi))'); - // or functions - $e->evaluate('f(x,y) = x^2 + y^2 - 2x*y + 1'); - // and then use them - $result = $e->evaluate('3*f(42,a)'); - ?> - -DESCRIPTION - Use the Expressoion class when you want to evaluate mathematical or boolean - expressions from untrusted sources. You can define your own variables and - functions, which are stored in the object. Try it, it's fun! - - Based on http://www.phpclasses.org/browse/file/11680.html, cred to Miles Kaufmann - -METHODS - $e->evalute($expr) - Evaluates the expression and returns the result. If an error occurs, - prints a warning and returns false. If $expr is a function assignment, - returns true on success. - - $e->e($expr) - A synonym for $e->evaluate(). - - $e->vars() - Returns an associative array of all user-defined variables and values. - - $e->funcs() - Returns an array of all user-defined functions. - -PARAMETERS - $e->suppress_errors - Set to true to turn off warnings when evaluating expressions - - $e->last_error - If the last evaluation failed, contains a string describing the error. - (Useful when suppress_errors is on). - -AUTHORS INFORMATION - Copyright 2005, Miles Kaufmann. - Copyright 2016, Jakub Jankiewicz - -LICENSE - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions are - met: - - 1 Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - 2. Redistributions in binary form must reproduce the above copyright - notice, this list of conditions and the following disclaimer in the - documentation and/or other materials provided with the distribution. - 3. The name of the author may not be used to endorse or promote - products derived from this software without specific prior written - permission. - - THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR - IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED - WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE - DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, - INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES - (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR - SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, - STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN - ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - POSSIBILITY OF SUCH DAMAGE. - -*/ - -class Expression -{ - - var $suppress_errors = false; - var $last_error = null; - - var $v = array('e' => 2.71, 'pi' => 3.14); // variables (and constants) - var $f = array(); // user-defined functions - var $vb = array('e', 'pi'); // constants - var $fb = array( // built-in functions - 'sin', 'sinh', 'arcsin', 'asin', 'arcsinh', 'asinh', - 'cos', 'cosh', 'arccos', 'acos', 'arccosh', 'acosh', - 'tan', 'tanh', 'arctan', 'atan', 'arctanh', 'atanh', - 'sqrt', 'abs', 'ln', 'log'); - - var $functions = array(); // function defined outside of Expression as closures - - function __construct() - { - // make the variables a little more accurate - $this->v['pi'] = pi(); - $this->v['e'] = exp(1); - } - - function e($expr) - { - return $this->evaluate($expr); - } - - function evaluate($expr) - { - $this->last_error = null; - $expr = trim($expr); - if (substr($expr, -1, 1) == ';') $expr = substr($expr, 0, strlen($expr) - 1); // strip semicolons at the end - //=============== - // is it a variable assignment? - if (preg_match('/^\s*([a-z]\w*)\s*=(?!~|=)\s*(.+)$/', $expr, $matches)) { - if (in_array($matches[1], $this->vb)) { // make sure we're not assigning to a constant - return $this->trigger("cannot assign to constant '$matches[1]'"); - } - $tmp = $this->pfx($this->nfx($matches[2])); - $this->v[$matches[1]] = $tmp; // if so, stick it in the variable array - return $this->v[$matches[1]]; // and return the resulting value - //=============== - // is it a function assignment? - } elseif (preg_match('/^\s*([a-z]\w*)\s*\((?:\s*([a-z]\w*(?:\s*,\s*[a-z]\w*)*)\s*)?\)\s*=(?!~|=)\s*(.+)$/', $expr, $matches)) { - $fnn = $matches[1]; // get the function name - if (in_array($matches[1], $this->fb)) { // make sure it isn't built in - return $this->trigger("cannot redefine built-in function '$matches[1]()'"); - } - - if ($matches[2] != "") { - $args = explode(",", preg_replace("/\s+/", "", $matches[2])); // get the arguments - } else { - $args = array(); - } - if (($stack = $this->nfx($matches[3])) === false) return false; // see if it can be converted to postfix - for ($i = 0; $i < count($stack); $i++) { // freeze the state of the non-argument variables - $token = $stack[$i]; - if (preg_match('/^[a-z]\w*$/', $token) and !in_array($token, $args)) { - if (array_key_exists($token, $this->v)) { - $stack[$i] = $this->v[$token]; - } else { - return $this->trigger("undefined variable '$token' in function definition"); - } - } - } - $this->f[$fnn] = array('args' => $args, 'func' => $stack); - return true; - //=============== - } else { - return $this->pfx($this->nfx($expr)); // straight up evaluation, woo - } - } - - function vars() - { - $output = $this->v; - unset($output['pi']); - unset($output['e']); - return $output; - } - - function funcs() - { - $output = array(); - foreach ($this->f as $fnn => $dat) - $output[] = $fnn . '(' . implode(',', $dat['args']) . ')'; - return $output; - } - - //===================== HERE BE INTERNAL METHODS ====================\\ - - // Convert infix to postfix notation - function nfx($expr) - { - $index = 0; - $stack = new ExpressionStack; - $output = array(); // postfix form of expression, to be passed to pfx() - $expr = trim(strtolower($expr)); - - $ops = array('+', '-', '*', '/', '^', '_', '%', '>', '<', '>=', '<=', '==', '!=', '=~', '&&', '||', '!'); - $ops_r = array('+' => 0, '-' => 0, '*' => 0, '/' => 0, '%' => 0, '^' => 1, '>' => 0, - '<' => 0, '>=' => 0, '<=' => 0, '==' => 0, '!=' => 0, '=~' => 0, - '&&' => 0, '||' => 0, '!' => 0); // right-associative operator? - $ops_p = array('+' => 4, '-' => 4, '*' => 4, '/' => 4, '_' => 4, '%' => 4, '^' => 5, '>' => 2, '<' => 2, - '>=' => 2, '<=' => 2, '==' => 2, '!=' => 2, '=~' => 2, '&&' => 1, '||' => 1, '!' => 5); // operator precedence - - $expecting_op = false; // we use this in syntax-checking the expression - // and determining when a - is a negation - - /* we allow all characters because of strings - if (preg_match("%[^\w\s+*^\/()\.,-<>=&~|!\"\\\\/]%", $expr, $matches)) { // make sure the characters are all good - return $this->trigger("illegal character '{$matches[0]}'"); - } - */ - $first_argument = false; - while (1) { // 1 Infinite Loop ;) - $op = substr($expr, $index, 2); // get the first two characters at the current index - if (preg_match("/^[+\-*\/^_\"<>=%(){\[!~,](?!=|~)/", $op) || preg_match("/\w/", $op)) { - // fix $op if it should have one character - $op = substr($expr, $index, 1); - } - $single_str = '(?"(?:[^"]|\\\\")*"|[^[{\]}]|(?1))*[\]}]'; - $number = '[\d.]+e\d+|\d+(?:\.\d*)?|\.\d+'; - $name = '[a-z]\w*\(?|\\$\w+'; - $parenthesis = '\\('; - // find out if we're currently at the beginning of a number/string/object/array/variable/function/parenthesis/operand - $ex = preg_match("%^($single_str|$double_str|$json|$name|$number|$parenthesis)%", substr($expr, $index), $match); - //=============== - if ($op == '[' && $expecting_op && $ex) { - if (!preg_match("/^\[(.*)\]$/", $match[1], $matches)) { - return $this->trigger("invalid array access"); - } - $stack->push('['); - $stack->push($matches[1]); - $index += strlen($match[1]); - //} elseif ($op == '!' && !$expecting_op) { - // $stack->push('!'); // put a negation on the stack - // $index++; - } elseif ($op == '-' and !$expecting_op) { // is it a negation instead of a minus? - $stack->push('_'); // put a negation on the stack - $index++; - } elseif ($op == '_') { // we have to explicitly deny this, because it's legal on the stack - return $this->trigger("illegal character '_'"); // but not in the input expression - //=============== - } elseif (((in_array($op, $ops) or $ex) and $expecting_op) or in_array($op, $ops) and !$expecting_op) { - // are we putting an operator on the stack? - if ($ex) { // are we expecting an operator but have a number/variable/function/opening parethesis? - $op = '*'; - $index--; // it's an implicit multiplication - } - // heart of the algorithm: - while ($stack->count > 0 and ($o2 = $stack->last()) and in_array($o2, $ops) and ($ops_r[$op] ? $ops_p[$op] < $ops_p[$o2] : $ops_p[$op] <= $ops_p[$o2])) { - $output[] = $stack->pop(); // pop stuff off the stack into the output - - } - // many thanks: http://en.wikipedia.org/wiki/Reverse_Polish_notation#The_algorithm_in_detail - $stack->push($op); // finally put OUR operator onto the stack - $index++; - if (strlen($op) == 2) { - $index++; - } - $expecting_op = false; - //=============== - } elseif ($op == ')' and $expecting_op || !$ex) { // ready to close a parenthesis? - while (($o2 = $stack->pop()) != '(') { // pop off the stack back to the last ( - if (is_null($o2)) return $this->trigger("unexpected ')'"); - else $output[] = $o2; - } - if (preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) { // did we just close a function? - $fnn = $matches[1]; // get the function name - $arg_count = $stack->pop(); // see how many arguments there were (cleverly stored on the stack, thank you) - $output[] = $stack->pop(); // pop the function and push onto the output - if (in_array($fnn, $this->fb)) { // check the argument count - if ($arg_count > 1) - return $this->trigger("too many arguments ($arg_count given, 1 expected)"); - } elseif (array_key_exists($fnn, $this->f)) { - if ($arg_count != count($this->f[$fnn]['args'])) - return $this->trigger("wrong number of arguments ($arg_count given, " . count($this->f[$fnn]['args']) . " expected) " . json_encode($this->f[$fnn]['args'])); - } elseif (array_key_exists($fnn, $this->functions)) { - $func_reflection = new ReflectionFunction($this->functions[$fnn]); - $count = $func_reflection->getNumberOfParameters(); - if ($arg_count != $count) - return $this->trigger("wrong number of arguments ($arg_count given, " . $count . " expected)"); - } else { // did we somehow push a non-function on the stack? this should never happen - return $this->trigger("internal error"); - } - } - $index++; - //=============== - } elseif ($op == ',' and $expecting_op) { // did we just finish a function argument? - - while (($o2 = $stack->pop()) != '(') { - if (is_null($o2)) return $this->trigger("unexpected ','"); // oops, never had a ( - else $output[] = $o2; // pop the argument expression stuff and push onto the output - } - // make sure there was a function - if (!preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) - return $this->trigger("unexpected ','"); - if ($first_argument) { - $first_argument = false; - } else { - $stack->push($stack->pop() + 1); // increment the argument count - } - $stack->push('('); // put the ( back on, we'll need to pop back to it again - $index++; - $expecting_op = false; - //=============== - } elseif ($op == '(' and !$expecting_op) { - $stack->push('('); // that was easy - $index++; -// $allow_neg = true; - //=============== - } elseif ($ex and !$expecting_op) { // do we now have a function/variable/number? - $expecting_op = true; - $val = $match[1]; - if ($op == '[' || $op == "{" || preg_match("/null|true|false/", $match[1])) { - $output[] = $val; - } elseif (preg_match("/^([a-z]\w*)\($/", $val, $matches)) { // may be func, or variable w/ implicit multiplication against parentheses... - if (in_array($matches[1], $this->fb) or - array_key_exists($matches[1], $this->f) or - array_key_exists($matches[1], $this->functions) - ) { // it's a func - $stack->push($val); - $stack->push(0); - $stack->push('('); - $expecting_op = false; - } else { // it's a var w/ implicit multiplication - $val = $matches[1]; - $output[] = $val; - } - } else { // it's a plain old var or num - $output[] = $val; - if (preg_match("/^([a-z]\w*)\($/", $stack->last(3))) { - $first_argument = true; - while (($o2 = $stack->pop()) != '(') { - if (is_null($o2)) return $this->trigger("unexpected error"); // oops, never had a ( - else $output[] = $o2; // pop the argument expression stuff and push onto the output - } - // make sure there was a function - if (!preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) - return $this->trigger("unexpected error"); - - $stack->push($stack->pop() + 1); // increment the argument count - $stack->push('('); // put the ( back on, we'll need to pop back to it again - } - } - $index += strlen($val); - //=============== - } elseif ($op == ')') { // miscellaneous error checking - return $this->trigger("unexpected ')'"); - } elseif (in_array($op, $ops) and !$expecting_op) { - return $this->trigger("unexpected operator '$op'"); - } else { // I don't even want to know what you did to get here - return $this->trigger("an unexpected error occured " . json_encode($op) . " " . json_encode($match) . " " . ($ex ? 'true' : 'false') . " " . $expr); - } - if ($index == strlen($expr)) { - if (in_array($op, $ops)) { // did we end with an operator? bad. - return $this->trigger("operator '$op' lacks operand"); - } else { - break; - } - } - while (substr($expr, $index, 1) == ' ') { // step the index past whitespace (pretty much turns whitespace - $index++; // into implicit multiplication if no operator is there) - } - - } - while (!is_null($op = $stack->pop())) { // pop everything off the stack and push onto output - if ($op == '(') return $this->trigger("expecting ')'"); // if there are (s on the stack, ()s were unbalanced - $output[] = $op; - } - return $output; - } - - // evaluate postfix notation - function pfx($tokens, $vars = array()) - { - - if ($tokens == false) return false; - $stack = new ExpressionStack(); - foreach ($tokens as $token) { // nice and easy - // if the token is a binary operator, pop two values off the stack, do the operation, and push the result back on - if (in_array($token, array('+', '-', '*', '/', '^', '<', '>', '<=', '>=', '==', '&&', '||', '!=', '=~', '%'))) { - $op2 = $stack->pop(); - $op1 = $stack->pop(); - switch ($token) { - case '+': - if (is_string($op1) || is_string($op2)) { - $stack->push((string)$op1 . (string)$op2); - } else { - $stack->push($op1 + $op2); - } - break; - case '-': - $stack->push($op1 - $op2); - break; - case '*': - $stack->push($op1 * $op2); - break; - case '/': - if ($op2 == 0) return $this->trigger("division by zero"); - $stack->push($op1 / $op2); - break; - case '%': - $stack->push($op1 % $op2); - break; - case '^': - $stack->push(pow($op1, $op2)); - break; - case '>': - $stack->push($op1 > $op2); - break; - case '<': - $stack->push($op1 < $op2); - break; - case '>=': - $stack->push($op1 >= $op2); - break; - case '<=': - $stack->push($op1 <= $op2); - break; - case '==': - if (is_array($op1) && is_array($op2)) { - $stack->push(json_encode($op1) == json_encode($op2)); - } else { - $stack->push($op1 == $op2); - } - break; - case '!=': - if (is_array($op1) && is_array($op2)) { - $stack->push(json_encode($op1) != json_encode($op2)); - } else { - $stack->push($op1 != $op2); - } - break; - case '=~': - $value = @preg_match($op2, $op1, $match); - - if (!is_int($value)) { - return $this->trigger("Invalid regex " . json_encode($op2)); - } - $stack->push($value); - for ($i = 0; $i < count($match); $i++) { - $this->v['$' . $i] = $match[$i]; - } - break; - case '&&': - $stack->push($op1 ? $op2 : $op1); - break; - case '||': - $stack->push($op1 ? $op1 : $op2); - break; - } - // if the token is a unary operator, pop one value off the stack, do the operation, and push it back on - } elseif ($token == '!') { - $stack->push(!$stack->pop()); - } elseif ($token == '[') { - $selector = $stack->pop(); - $object = $stack->pop(); - if (is_object($object)) { - $stack->push($object->$selector); - } elseif (is_array($object)) { - $stack->push($object[$selector]); - } else { - return $this->trigger("invalid object for selector"); - } - } elseif ($token == "_") { - $stack->push(-1 * $stack->pop()); - // if the token is a function, pop arguments off the stack, hand them to the function, and push the result back on - } elseif (preg_match("/^([a-z]\w*)\($/", $token, $matches)) { // it's a function! - $fnn = $matches[1]; - if (in_array($fnn, $this->fb)) { // built-in function: - if (is_null($op1 = $stack->pop())) return $this->trigger("internal error"); - $fnn = preg_replace("/^arc/", "a", $fnn); // for the 'arc' trig synonyms - if ($fnn == 'ln') $fnn = 'log'; - $stack->push($fnn($op1)); // perfectly safe variable function call - } elseif (array_key_exists($fnn, $this->f)) { // user function - // get args - $args = []; - for ($i = count($this->f[$fnn]['args']) - 1; $i >= 0; $i--) { - if ($stack->isEmpty()) { - return $this->trigger("internal error " . $fnn . " " . json_encode($this->f[$fnn]['args'])); - } - $args[$this->f[$fnn]['args'][$i]] = $stack->pop(); - } - $stack->push($this->pfx($this->f[$fnn]['func'], $args)); // yay... recursion!!!! - } else if (array_key_exists($fnn, $this->functions)) { - $reflection = new ReflectionFunction($this->functions[$fnn]); - $count = $reflection->getNumberOfParameters(); - $args = []; - for ($i = $count - 1; $i >= 0; $i--) { - if ($stack->isEmpty()) { - return $this->trigger("internal error"); - } - $args[] = $stack->pop(); - } - $stack->push($reflection->invokeArgs($args)); - } - // if the token is a number or variable, push it on the stack - } else { - if (preg_match('/^([\[{](?>"(?:[^"]|\\")*"|[^[{\]}]|(?1))*[\]}])$/', $token) || - preg_match("/^(null|true|false)$/", $token) - ) { // json - //return $this->trigger("invalid json " . $token); - if ($token == 'null') { - $value = null; - } elseif ($token == 'true') { - $value = true; - } elseif ($token == 'false') { - $value = false; - } else { - $value = json_decode($token); - if ($value == null) { - return $this->trigger("invalid json " . $token); - } - } - $stack->push($value); - } elseif (is_numeric($token)) { - $stack->push(0 + $token); - } else if (preg_match("/^['\\\"](.*)['\\\"]$/", $token)) { - $stack->push(json_decode(preg_replace_callback("/^['\\\"](.*)['\\\"]$/", function ($matches) { - $m = array("/\\\\'/", '/(?v)) { - $stack->push($this->v[$token]); - } elseif (array_key_exists($token, $vars)) { - $stack->push($vars[$token]); - } else { - return $this->trigger("undefined variable '$token'"); - } - } - } - // when we're out of tokens, the stack should have a single element, the final result - if ($stack->count != 1) return $this->trigger("internal error"); - return $stack->pop(); - } - - /** - * trigger an error, but nicely, if need be - * @param string $msg - * @return bool - */ - function trigger($msg) - { - $this->last_error = $msg; - if (!$this->suppress_errors) trigger_error($msg, E_USER_WARNING); - return false; - } -} +namespace optimistex\expression; /** - * for internal use + * Class Expression adapted for Yii2 + * @package optimistex\expression */ -class ExpressionStack +class Expression extends \Expression { - var $stack = array(); - var $count = 0; - - function push($val) - { - $this->stack[$this->count] = $val; - $this->count++; - } - - function pop() - { - if ($this->count > 0) { - $this->count--; - return $this->stack[$this->count]; - } - return null; - } - - function isEmpty() - { - return empty($this->stack); - } - function last($n = 1) - { - if (isset($this->stack[$this->count - $n])) { - return $this->stack[$this->count - $n]; - } - return null; - } } \ No newline at end of file diff --git a/ExpressionCore.php b/ExpressionCore.php deleted file mode 100644 index 2ec4f11..0000000 --- a/ExpressionCore.php +++ /dev/null @@ -1,18 +0,0 @@ -