Last updated: Fri, 13 Nov 2009

debug_backtrace

(PHP 4 >= 4.3.0, PHP 5)

debug_backtrace — Generates a backtrace

Descrição

array debug_backtrace ([ bool $provide_object = true ] )

debug_backtrace() generates a PHP backtrace.

Parâmetros

provide_object: Whether or not to populate the "object" index. Defaults to TRUE.

Valor Retornado

Returns an associative array. The possible returned elements are as follows:

Possible returned elements from **debug_backtrace()**
Nome	Tipo	Descrição
function	string	The current function name. See also __FUNCTION__.
line	integer	The current line number. See also __LINE__.
file	string	The current file name. See also __FILE__.
class	string	The current class name. See also __CLASS__
object	object	The current object.
type	string	The current call type. If a method call, "->" is returned. If a static method call, "::" is returned. If a function call, nothing is returned.
args	array	If inside a function, this lists the functions arguments. If inside an included file, this lists the included file name(s).

Histórico

Versão	Descrição
5.2.5	Added the optional parameter `provide_object` .
5.1.1	Added the current object as a possible return element.

Exemplos

Exemplo #1 debug_backtrace() example


<?php
// filename: /tmp/a.php

function a_test($str)
{
    echo "\nHi: $str";
    var_dump(debug_backtrace());
}

a_test('friend');
?>

<?php
// filename: /tmp/b.php
include_once '/tmp/a.php';
?>

Results similar to the following when executing /tmp/b.php:

Hi: friend
array(2) {
[0]=>
array(4) {
    ["file"] => string(10) "/tmp/a.php"
    ["line"] => int(10)
    ["function"] => string(6) "a_test"
    ["args"]=>
    array(1) {
      [0] => &string(6) "friend"
    }
}
[1]=>
array(4) {
    ["file"] => string(10) "/tmp/b.php"
    ["line"] => int(2)
    ["args"] =>
    array(1) {
      [0] => string(10) "/tmp/a.php"
    }
    ["function"] => string(12) "include_once"
  }
}

Veja Também

trigger_error() - Gera uma mensagem a nível de usuário de erro/aviso/notícia
debug_print_backtrace() - Mostra um backtrace

debug_print_backtrace

Funções para Manuseamento de Erros

Last updated: Fri, 13 Nov 2009

add a note User Contributed Notes
debug_backtrace

michael dot schramm at gmail dot com
20-Oct-2009 05:29


Be carefull if you are using objects as arguments for function calls!



<?php

error_reporting(E_ALL);



function myPrint($trace){

    foreach($trace as $i=>$call){

        /**

         * THIS IS NEEDED! If all your objects have a __toString function it's not needed!

         * 

         * Catchable fatal error: Object of class B could not be converted to string

         * Catchable fatal error: Object of class A could not be converted to string

         * Catchable fatal error: Object of class B could not be converted to string

         */

        if (is_object($call['object'])) { $call['object'] = 'CONVERTED OBJECT OF CLASS '.get_class($call['object']); }

        if (is_array($call['args'])) {

            foreach ($call['args'] AS &$arg) {

                if (is_object($arg)) { $arg = 'CONVERTED OBJECT OF CLASS '.get_class($arg); }

            }

        }

        

        $trace_text[$i] = "#".$i." ".$call['file'].'('.$call['line'].') ';

        $trace_text[$i].= (!empty($call['object'])?$call['object'].$call['type']:'');

        $trace_text[$i].= $call['function'].'('.implode(', ',$call['args']).')';

    }

    

    var_dump($trace_text);

}



class A{

    public function test($obj){

        $obj->test();

    }

}



class B{

    public function test(){

        echo myPrint(debug_backtrace());

    }

}



$A = new A();

$B = new B();



$A->test($B);



?>

profix at cms-studio dot net
04-Aug-2009 11:30


Maybe it can be useful ... :)



<?



function IsRecursiveCall()

{

$ret=false;

$cc=debug_backtrace();

$thisfunction=array_shift($cc);

if ($callerfunction=array_shift($cc))

  {

  $name=$callerfunction["function"];

  reset($cc);

  while ($cx=each($cc))

    if ($ret=($cx["value"]["function"]==$name))

      break;

  }

return $ret;

}



function GetRecursiveCallLevel()

{

$ret=0;

$cc=debug_backtrace();

$thisfunction=array_shift($cc);

if ($callerfunction=array_shift($cc))

  {

  $name=$callerfunction["function"];

  reset($cc);

  while ($cx=each($cc))

    if ($cx["value"]["function"]==$name)

      $ret++;

  }

return $ret;

}



// -- example --------------------------



function RecursiveFunction()

{

echo "Recursive function begin.\n";



$level=GetRecursiveCallLevel();

echo "Recursive level is: ".$level."\n";



echo "Is it recursive ? ";

if (IsRecursiveCall()) echo "yes"; else echo "no";

echo "\n";



if ($level<5)

  RecursiveFunction();



echo "Recursive function end.\n";

}



// -----------------------



echo "<pre>\n";

RecursiveFunction();

echo "</pre>\n";



?>



Output is:



Recursive function begin.

Recursive level is: 0

Is it recursive ? no

Recursive function begin.

Recursive level is: 1

Is it recursive ? yes

Recursive function begin.

Recursive level is: 2

Is it recursive ? yes

Recursive function begin.

Recursive level is: 3

Is it recursive ? yes

Recursive function begin.

Recursive level is: 4

Is it recursive ? yes

Recursive function begin.

Recursive level is: 5

Is it recursive ? yes

Recursive function end.

Recursive function end.

Recursive function end.

Recursive function end.

Recursive function end.

Recursive function end.

passionplay at hotmail dot com
12-Oct-2008 12:42


My two cents. See my XML Handler which uses this class.



<?php

// Basic error functions

class errorBase

{

    function backtrace($provideObject=false)

    {

        foreach(debug_backtrace($provideObject) as $row)

        {

            if($last!=$row['file'])

                echo "File: $file<br>\n'";

      $last=$row['file'];

            echo " Line: $row[line]: ";

            if($row['class']!='')

                echo "$row[class]$row[type]$row[function]";

            else

                echo "$row[function]";

            echo "(";

            echo join("', '",$args);

            echo ")<br>\n";

        }

    }

    function error($msg,$fatal=false)

    {

        echo "<div align=\"center\"><font color=\"red\"><b>Error: $msg</b></font></div>";

        $last='';

        $this->backtrace();

        exit();

    }

    function fatalError($msg){return $this->error($msg,true);}

}

?>

Force Flow
24-Sep-2008 11:43


I think I worked out an easy way to get the trace printed out in an easily readable format with minimal code:





<?php


    echo parse_backtrace(debug_backtrace());





    function parse_backtrace($raw){





        $output="";


        


        foreach($raw as $entry){


                $output.="\nFile: ".$entry['file']." (Line: ".$entry['line'].")\n";


                $output.="Function: ".$entry['function']."\n";


                $output.="Args: ".implode(", ", $entry['args'])."\n";


        }





        return $output;


    }


?>

frank at frank dot com
07-May-2008 04:12


Here is my simple example:

Code printing variable of class which instatiates the printing class.



Well, I am sure you understand when looking at the code:

Print result is: jippii



<?php

class A {



        function something() {

                $s = debug_backtrace();

                

                $callingObject = $s[1]['object']; 

                $test = $callingObject->jip;

                print $test;

        }



}



class B {

      var $jip; 

      

        function execute() {

                $a = new A();

                $this->jip = "jippii";  

                $a->something(); 

        }



}

$control = new B();

$control->execute();

?>

samthor
11-Feb-2008 06:04


Here's a way to get the arguments for an upstream function in your stack (works with class methods, static methods and non-class methods):

<?php

/**

 * getArgs - find arguments of upstream method

 * can be called with, e.g. "funcname", "class::staticmethod", "class->instancemethod".

 */

function getArgs( $target, $subclass_ok = true ) {



    if( strpos( $target, "::" ) ) {

        list( $class, $target ) = explode( "::", $target, 2 );

        $type = "::";

    }

    else if( strpos( $target, "->" ) ) {

        list( $class, $target ) = explode( "->", $target, 2 );

        $type = "->";

    }

    else {

        $type = NULL;

        $class = NULL;

    }

    $class and $class = new ReflectionClass( $class );



    foreach( debug_backtrace() as $obj ) {



        if( $obj['function'] == $target ) {

            if( $type and $obj['type'] == $type ) {

                $_cl = new ReflectionClass( $obj['class'] );

                if( $_cl->getName() == $class->getName() or ( $subclass_ok and $_cl->isSubclassOf( $class ) ) ) {

                    return $obj['args'];

                }

                unset( $_cl );

            }

            else if( !$type ) {

                return $obj['args'];

            }

        }



    }



    return NULL;



}

?>



Some example usage:

<?php

class Foo {

    function test() {

        $args = getArgs( "Foo->base" );

        print( "the parameter 'v' to my call of base was: {$args[0]}\n" );

    }

    function base( $v ) {

        $this->test();

    }

}



$f = new Foo();

$f->base( 713 ); // will print.. ".. my call of base was: 713"



?>



Trust me, there are some reasons for why you might want to do this :)

aryel at iku dot com dot br
29-Jan-2008 08:40


An easy function to pull all details of the debug backtrace:



<?php

function getDebugBacktrace($NL = "<BR>") {

    $dbgTrace = debug_backtrace();

    $dbgMsg .= $NL."Debug backtrace begin:$NL";

    foreach($dbgTrace as $dbgIndex => $dbgInfo) {

        $dbgMsg .= "\t at $dbgIndex  ".$dbgInfo['file']." (line {$dbgInfo['line']}) -> {$dbgInfo['function']}(".join(",",$dbgInfo['args'])")$NL";

    }

    $dbgMsg .= "Debug backtrace end".$NL;

    return $dbgMsg;

}

?>



Then you can call it anywhere you want to get a string with the debug backtrace in readable format (i.e. your error handling function)



<?php

$backtrace = getDebugBacktrace();

echo "Fatal error! Cannot connect to database!";

echo $backtrace;

?>



If you're running on command line, you might want to replace the line split. You can do that thru the function argument:



<?php

$backtrace = getDebugBacktrace("\n");

echo "Error! Server is running out of foos! Dumping error backtrace";

echo $backtrace;

?>



Hope that helps,

Aryel

misterpib at gmail dot com
17-Oct-2007 02:35


You should probably try to avoid changing any of the items in the args array. Consider this example:

----------

function a(&$value)

{

  echo "start a: $value\n";

  b();

  echo "end a: $value\n";

}



function b()

{

  echo "start b\n";

  $stack = debug_backtrace();

  $stack[1]['args'][0] = 'bob';

  echo "end b\n";

}



$mynum = 42;

a($mynum);

--------------



This prints:



start a: 42

start b

end b

end a: bob

php at kennel17 dot co dot uk
20-Jun-2007 02:30


Further to my previous note, the 'object' element of the array can be used to get the parent object.  So changing the get_class_static() function to the following will make the code behave as expected:



<?php

    function get_class_static() {

        $bt = debug_backtrace();

    

        if (isset($bt[1]['object']))

            return get_class($bt[1]['object']);

        else

            return $bt[1]['class'];

    }

?>



HOWEVER, it still fails when being called statically.  Changing the last two lines of my previous example to



<?php

  foo::printClassName();

  bar::printClassName();

?>



...still gives the same problematic result in PHP5, but in this case the 'object' property is not set, so that technique is unavailable.

php at kennel17 dot co dot uk
20-Jun-2007 02:01


The value of the class argument has changed slightly between PHP4 and PHP5:



Here's an example:



<?php



  function get_class_static() {

    $bt = debug_backtrace();

    $name = $bt[1]['class'];

    return $name;

  }



  class foo {

    function printClassName() {

      print(get_class_static() . "\n");

     }

  }



  class bar extends foo {

  }



$f = new foo();

$b = new bar();

$f->printClassName();

$b->printClassName();



?>



In PHP4 you get:



  foo

  bar



In PHP5 you get:



  foo

  foo



debug_backtrace() now sets the 'class' parameter to be the class that the function is actually defined in, not the name of the instantiated class.

jsnell at e-normous dot com
30-May-2007 07:35


If you are using the backtrace function in an error handler, avoid using var_export() on the args, as you will cause fatal errors in some situations, preventing you from seeing your stack trace.  Some structures will cause PHP to generate the fatal error "Nesting level too deep - recursive dependency?" This is a design feature of php, not a bug (see http://bugs.php.net/bug.php?id=30471)

kroczu AT interia DOT pl
23-Jan-2007 04:24


<?

// useful and comfortable debug function

// it's show memory usage and time flow between calls, so we can quickly find a block of code that need optimisation...

// example result:

/*

debug example.php> initialize

debug example.php> code-lines: 39-41 time: 2.0002 mem: 19 KB

debug example.php> code-lines: 41-44 time: 0.0000 mem: 19 KB

debug example.php> code-lines: 44-51 time: 0.6343 mem: 9117 KB

debug example.php> code-lines: 51-53 time: 0.1003 mem: 9117 KB

debug example.php> code-lines: 53-55 time: 0.0595 mem: 49 KB

 */



function debug()

{

   static $start_time = NULL;

   static $start_code_line = 0;



   $call_info = array_shift( debug_backtrace() );

   $code_line = $call_info['line'];

   $file = array_pop( explode('/', $call_info['file']));



   if( $start_time === NULL )

   {

       print "debug ".$file."> initialize\n";

       $start_time = time() + microtime();

       $start_code_line = $code_line;

       return 0;

   }



   printf("debug %s> code-lines: %d-%d time: %.4f mem: %d KB\n", $file, $start_code_line, $code_line, (time() + microtime() - $start_time), ceil( memory_get_usage()/1024));

   $start_time = time() + microtime();

   $start_code_line = $code_line;

}



////////////////////////////////////////////////

// example:



debug();

sleep(2);

debug();

// soft-code...

$a = 3 + 5;

debug();



// hard-code

for( $i=0; $i<100000; $i++)

{

    $dummy['alamakota'.$i] = 'alamakota'.$i;

}

debug();

usleep(100000);

debug();

unset($dummy);

debug();



?>

seaside dot ki at mac dot com
14-Dec-2006 10:20


I've started creating an external debug server for PHP. A PHP app require_once's a TADebugger(), which communicates with the debug sever. Find the OS X universal binary here [PHP source sample included]:



   http://www.turingart.com/downloads/phpDebugger.zip



Currently, TADebugger allows to post these properties back to the debug server:



- Call backtraces

- String messages

- Source files, which were referenced by a backtrace call



Note, that the binary is a early version.

icefragment at gmail dot com
23-Sep-2006 02:34


A simple python-like backtrace. Note that I don't recurse into arrays if they are passed as arguments to functions.



function backtrace()

{

    $bt = debug_backtrace();

    

    echo("<br /><br />Backtrace (most recent call last):<br /><br />\n");    

    for($i = 0; $i <= count($bt) - 1; $i++)

    {

        if(!isset($bt[$i]["file"]))

            echo("[PHP core called function]<br />");

        else

            echo("File: ".$bt[$i]["file"]."<br />");

        

        if(isset($bt[$i]["line"]))

            echo("&nbsp;&nbsp;&nbsp;&nbsp;line ".$bt[$i]["line"]."<br />");

        echo("&nbsp;&nbsp;&nbsp;&nbsp;function called: ".$bt[$i]["function"]);

        

        if($bt[$i]["args"])

        {

            echo("<br />&nbsp;&nbsp;&nbsp;&nbsp;args: ");

            for($j = 0; $j <= count($bt[$i]["args"]) - 1; $j++)

            {

                if(is_array($bt[$i]["args"][$j]))

                {

                    print_r($bt[$i]["args"][$j]);

                }

                else

                    echo($bt[$i]["args"][$j]);    

                            

                if($j != count($bt[$i]["args"]) - 1)

                    echo(", ");

            }

        }

        echo("<br /><br />");

    }

}

zmorris at mac dot com
21-Sep-2006 12:48


Hi, I got tired of using a trace( $message, __FILE__, __LINE__ ) function I made.  It forced me to include the file and line params (since php doesn't have macros) so I decided to make an alternative.



Simply call this new version using trace( 'my message' ); and it prints out a stack trace in a clearer way than the one stored in the debug_backtrace() array.  It handles traces from outside of functions, traces in nested functions, and traces in included files, and also displays the function in a way that can be pasted right back into your php code for faster testing!



NOTE - be sure to save your files with the correct line endings for the line numbers to work correctly, which for Mac OS X is unix.  You can get to this option in the popup menu in the toolbar at the top of each window in BBEdit.



<?php



function    print_var( $var )

{

   if( is_string( $var ) )

       return( '"'.str_replace( array("\x00", "\x0a", "\x0d", "\x1a", "\x09"), array('\0', '\n', '\r', '\Z', '\t'), $var ).'"' );

   else if( is_bool( $var ) )

   {

       if( $var )

           return( 'true' );

       else

           return( 'false' );

   }

   else if( is_array( $var ) )

   {

       $result = 'array( ';

       $comma = '';

       foreach( $var as $key => $val )

       {

           $result .= $comma.print_var( $key ).' => '.print_var( $val );

           $comma = ', ';

       }

       $result .= ' )';

       return( $result );

   }

   

   return( var_export( $var, true ) );    // anything else, just let php try to print it

}



function    trace( $msg )

{

   echo "<pre>\n";

   

   //var_export( debug_backtrace() ); echo "</pre>\n"; return;    // this line shows what is going on underneath

   

   $trace = array_reverse( debug_backtrace() );

   $indent = '';

   $func = '';

   

   echo $msg."\n";

   

   foreach( $trace as $val)

   {

       echo $indent.$val['file'].' on line '.$val['line'];

       

       if( $func ) echo ' in function '.$func;

       

       if( $val['function'] == 'include' ||

           $val['function'] == 'require' ||

           $val['function'] == 'include_once' ||

           $val['function'] == 'require_once' )

           $func = '';

       else

       {

           $func = $val['function'].'(';

           

           if( isset( $val['args'][0] ) )

           {

               $func .= ' ';

               $comma = '';

               foreach( $val['args'] as $val )

               {

                   $func .= $comma.print_var( $val );

                   $comma = ', ';

               }

               $func .= ' ';

           }

           

           $func .= ')';

       }

       

       echo "\n";

       

       $indent .= "\t";

   }

   

   echo "</pre>\n";

}



trace( 'error outside function' );



function    test( $param1, $param2, $param3, $param4 )

{

   trace( 'error in test()' );

}



test( 1.1, "param2\n", array( 1 => "a\n", "b\n" => 2 ), false );



?>

admin at sgssweb dot com
13-Aug-2006 07:30


Surprizingly, debug_backtrace() cannot aquire arguments from the function that is used as the second or later argument of a function.



<?php



function a($p) {

    $backtrace = debug_backtrace();

    

    if (isset($backtrace[0]['args']))

        var_export($backtrace[0]['args']);

    else

        echo "Cannot aquire arguments";

    echo "<br />";

    

    return $p;

}



function b($p1, $p2, $p3) {

    echo "$p1, $p2, $p3";

}



// This outputs:

//    array ( 0 => 'First a', )

//    Cannot aquire arguments

//    Cannot aquire arguments

//    First a, Second a, Third a

b(a("First a"), a("Second a"), a("Third a"));



?>

tiwen at rpgame dot de
30-Apr-2006 06:25


Another debug output. This is a short function that does not display the args (sometimes password are in arguments ...) and shows the callstack clearly in a table. In most cases i don't need more ...



<?php

function dieDebug($sError)

{

    echo "<hr /><div>".$sError."<br /><table border='1'>";

    $sOut=""; $aCallstack=debug_backtrace();

    

    echo "<thead><tr><th>file</th><th>line</th><th>function</th>".

        "</tr></thead>";

    foreach($aCallstack as $aCall)

    {

        if (!isset($aCall['file'])) $aCall['file'] = '[PHP Kernel]';

        if (!isset($aCall['line'])) $aCall['line'] = '';



        echo "<tr><td>{$aCall["file"]}</td><td>{$aCall["line"]}</td>".

            "<td>{$aCall["function"]}</td></tr>";

    }

    echo "</table></div><hr /></p>";

    die();

}

?>



To use it, simply do something like this:



<?php

if(...) dieDebug("another error found!");

?>

http://synergy8.com
14-Dec-2005 04:37


It should be noted that if an internal php function such as call_user_func in the backtrace, the 'file' and 'line' entries will not be set.



Most debug tracers will use these entries.  You should place a check to see if the key exists in the array before using this function.  Otherwise notices will be generated.



<?php



$arrTrace = debug_backtrace();



foreach ($arrTrace as $arr)

{

    if (!isset ($arr['file']))

    {

        $arr['file'] = '[PHP Kernel]';

    }



    if (!isset ($arr['line']))

    {

        $arr['line'] = '';

    }



    // Do something

}



?>

tb
21-Jul-2005 04:18


I use this for debugging in my object oriented systems.  It allows me to output a debug/error/warning function with exact information about the location that the error was thrown, which is useful.  Check it:



<?php

abstract class Debugger {

    

    /**

     * Throw a debug message.

     */

    abstract function debug($msg);

    

    /**

     * Throw an error message.

     */

    abstract function error($msg);

    

    /**

     * Throw a warning message.

     */

    abstract function warning($msg);

    

    /**

     * Wrap a message with information about class, function, file and line

     * number and return it.

     */

    protected function getMsg($msg) {

        $bt = debug_backtrace();

        

        // get class, function called by caller of caller of caller

        $class = $bt[2]['class'];

        $function = $bt[2]['function'];

        

        // get file, line where call to caller of caller was made

        $file = $bt[1]['file'];

        $line = $bt[1]['line'];

        

        // build & return the message

        return "$class::$function: $msg in $file at $line";

    }

    

}

?>



Implement different debuggers for different scenarios (development, testing, production).  Each debugger extends Debugger; each of its methods (debug/error/warning) calls $this->getMsg($msg) to get a message with class, function, file, and line information.  Then it can either log it, email it, die with it, etc.



Then, just give each object (perhaps using a common superclass Object) a concrete debugger.  Then, from any object method, do something like:



<?php

class Foo extends Object {

     function bar() {

          $this->debugger->error("This is an error");

     }

}

?>



Which produces something like:



Foo::bar: This is an error in /some/file at X

diz at ysagoon dot com
24-Nov-2004 08:35


Ok as spagmoid already said, I just realized that my function has a similar bug than jlim's function.



So just add the following line:

if (is_array($bt['args']))

before line:

foreach ($bt['args'] as $a) {



This way you avoid the warning from being displayed.

diz at ysagoon dot com
23-Nov-2004 08:40


And here are my two cents for a useful and good looking backtrace function.



<?php



function backtrace()

{

    $output = "<div style='text-align: left; font-family: monospace;'>\n";

    $output .= "<b>Backtrace:</b><br />\n";

    $backtrace = debug_backtrace();



    foreach ($backtrace as $bt) {

        $args = '';

        foreach ($bt['args'] as $a) {

            if (!empty($args)) {

                $args .= ', ';

            }

            switch (gettype($a)) {

            case 'integer':

            case 'double':

                $args .= $a;

                break;

            case 'string':

                $a = htmlspecialchars(substr($a, 0, 64)).((strlen($a) > 64) ? '...' : '');

                $args .= "\"$a\"";

                break;

            case 'array':

                $args .= 'Array('.count($a).')';

                break;

            case 'object':

                $args .= 'Object('.get_class($a).')';

                break;

            case 'resource':

                $args .= 'Resource('.strstr($a, '#').')';

                break;

            case 'boolean':

                $args .= $a ? 'True' : 'False';

                break;

            case 'NULL':

                $args .= 'Null';

                break;

            default:

                $args .= 'Unknown';

            }

        }

        $output .= "<br />\n";

        $output .= "<b>file:</b> {$bt['line']} - {$bt['file']}<br />\n";

        $output .= "<b>call:</b> {$bt['class']}{$bt['type']}{$bt['function']}($args)<br />\n";

    }

    $output .= "</div>\n";

    return $output;

}



?>



And here's a sample of how the output looks like (the last call is on the top):



Backtrace:



file: 56 - /tmp/test.php

call: backtrace()



file: 53 - /tmp/test.php

call: test->bar(15.4, Array(4))



file: 61 - /tmp/test.php

call: test->test("making new object", True)



file: 65 - /tmp/test.php

call: foo(Resource(#2), Null)

ad-rotator.com
30-Apr-2004 02:11


To simply print out the file/function trace (chain of calls, file and line number before the error):



function getTrace() {

 $vDebug = debug_backtrace();

 $vFiles = array();

 for ($i=0;$i<count($vDebug);$i++) {

   // skip the first one, since it's always this func

   if ($i==0) { continue; }

   $aFile = $vDebug[$i];

   $vFiles[] = '('.basename($aFile['file']).':'.$aFile['line'].')';

 } // for

 $vTraceStr = implode(',',$vFiles);

}

spagmoid at yahoo dot NOSPAMcom
09-Dec-2003 05:47


ATTN: jlim#natsoft.com.my



Great function, but you have a few bugs.



At the line: 

foreach($arr['args'] as $v)



Change it to:

$args = array();

if(!empty($arr['args'])) foreach($arr['args'] as $v)



And since line & file are not present in the array if calling from the error handler,



$Line = (isset($arr['line'])? $arr['line'] : "unknown");

$File = (isset($arr['file'])? $arr['file'] : "unknown");



and substitute accordingly.



Here's my version of it, alas with different formatting:

----------------------------------------



function DBG_GetBacktrace()

{

    $s = '';

    $MAXSTRLEN = 64;

    

    $s = '<pre align=left>';

    $traceArr = debug_backtrace();

    array_shift($traceArr);

    $tabs = sizeof($traceArr)-1;

    foreach($traceArr as $arr)

    {

        for ($i=0; $i < $tabs; $i++) $s .= ' &nbsp; ';

        $tabs -= 1;

        $s .= '<font face="Courier New,Courier">';

        if (isset($arr['class'])) $s .= $arr['class'].'.';

        $args = array();

        if(!empty($arr['args'])) foreach($arr['args'] as $v)

        {

            if (is_null($v)) $args[] = 'null';

            else if (is_array($v)) $args[] = 'Array['.sizeof($v).']';

            else if (is_object($v)) $args[] = 'Object:'.get_class($v);

            else if (is_bool($v)) $args[] = $v ? 'true' : 'false';

            else

            { 

                $v = (string) @$v;

                $str = htmlspecialchars(substr($v,0,$MAXSTRLEN));

                if (strlen($v) > $MAXSTRLEN) $str .= '...';

                $args[] = "\"".$str."\"";

            }

        }

        $s .= $arr['function'].'('.implode(', ',$args).')</font>';

        $Line = (isset($arr['line'])? $arr['line'] : "unknown");

        $File = (isset($arr['file'])? $arr['file'] : "unknown");

        $s .= sprintf("<font color=#808080 size=-1> # line %4d, file: <a href=\"file:/%s\">%s</a></font>",

            $Line, $File, $File);

        $s .= "\n";

    }    

    $s .= '</pre>';

    return $s;

}

Fabian dot Kraetzer at gmx dot de
01-Sep-2003 11:18


I coded a function, too. Just call debug() evertime you think you could encounter an error:

<?

    function debug()

    {

        $debug_array = debug_backtrace();

        $counter = count($debug_array);

        for($tmp_counter = 0; $tmp_counter != $counter; ++$tmp_counter)

        {

          ?>

          <table width="558" height="116" border="1" cellpadding="0" cellspacing="0" bordercolor="#000000">

            <tr>

              <td height="38" bgcolor="#D6D7FC"><font color="#000000">function <font color="#FF3300"><?

              echo($debug_array[$tmp_counter]["function"]);?>(</font> <font color="#2020F0"><?

              //count how many args a there

              $args_counter = count($debug_array[$tmp_counter]["args"]);

              //print them

              for($tmp_args_counter = 0; $tmp_args_counter != $args_counter; ++$tmp_args_counter)

              {

                 echo($debug_array[$tmp_counter]["args"][$tmp_args_counter]);



                 if(($tmp_args_counter + 1) != $args_counter)

                 {

                   echo(", ");

                 }

                 else

                 {

                   echo(" ");

                 }

              }

              ?></font><font color="#FF3300">)</font></font></td>

            </tr>

            <tr>

              <td bgcolor="#5F72FA"><font color="#FFFFFF">{</font><br>

                <font color="#FFFFFF">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;file: <?

                echo($debug_array[$tmp_counter]["file"]);?></font><br>

                <font color="#FFFFFF">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;line: <?

                echo($debug_array[$tmp_counter]["line"]);?></font><br>

                <font color="#FFFFFF">}</font></td>

            </tr>

          </table>

          <?

         if(($tmp_counter + 1) != $counter)

         {

           echo("<br>was called by:<br>");

         }

       }

        exit();

    }

?>

bernyregeling AT hotmail DOT com
08-Aug-2003 09:29


I wrote this function, in addition to jlim, for a nice NO-HTML output. 





Thee result has similarities to a Java-error. Hope you like it. 





(BTW, this function exits the script too, if debug_backtrace is displayed)


------------------------------


    function debug_bt()


    {


        if(!function_exists('debug_backtrace'))


        {


            echo 'function debug_backtrace does not exists'."\r\n";


            return;


        }


        //echo '<pre>';


        echo "\r\n".'----------------'."\r\n";


        echo 'Debug backtrace:'."\r\n";


        echo '----------------'."\r\n";


        foreach(debug_backtrace() as $t)


        {


            echo "\t" . '@ ';


            if(isset($t['file'])) echo basename($t['file']) . ':' . $t['line'];


            else


            {


                // if file was not set, I assumed the functioncall


                // was from PHP compiled source (ie XML-callbacks).


                echo '<PHP inner-code>';


            }





            echo ' -- ';





            if(isset($t['class'])) echo $t['class'] . $t['type'];





            echo $t['function'];





            if(isset($t['args']) && sizeof($t['args']) > 0) echo '(...)';


            else echo '()';





            echo "\r\n";


        }


        //echo '</pre>';


        exit;


         }

jlim#natsoft.com.my
13-Mar-2003 11:51


Pretty print the backtrace(). Functions are indented based on call value, and file is linked using file:// for convenience. 



Enjoy, John Lim



    function adodb_backtrace($print=true)

    {

        $s = '';

        if (PHPVERSION() >= 4.3) {

        

            $MAXSTRLEN = 64;

        

            $s = '<pre align=left>';

            $traceArr = debug_backtrace();

            array_shift($traceArr);

            $tabs = sizeof($traceArr)-1;

            foreach ($traceArr as $arr) {

                for ($i=0; $i < $tabs; $i++) $s .= ' &nbsp; ';

                $tabs -= 1;

                $s .= '<font face="Courier New,Courier">';

                if (isset($arr['class'])) $s .= $arr['class'].'.';

                foreach($arr['args'] as $v) {

                    if (is_null($v)) $args[] = 'null';

                    else if (is_array($v)) $args[] = 'Array['.sizeof($v).']';

                    else if (is_object($v)) $args[] = 'Object:'.get_class($v);

                    else if (is_bool($v)) $args[] = $v ? 'true' : 'false';

                    else { 

                        $v = (string) @$v;

                        $str = htmlspecialchars(substr($v,0,$MAXSTRLEN));

                        if (strlen($v) > $MAXSTRLEN) $str .= '...';

                        $args[] = $str;

                    }

                }

                

                $s .= $arr['function'].'('.implode(', ',$args).')';

                $s .= sprintf("</font><font color=#808080 size=-1> # line %4d,".

  " file: <a href=\"file:/%s\">%s</a></font>",

  $arr['line'],$arr['file'],$arr['file']);

                $s .= "\n";

            }    

            $s .= '</pre>';

            if ($print) print $s;

        }

        return $s;

    }

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debug_print_backtrace

Funções para Manuseamento de Erros

Last updated: Fri, 13 Nov 2009