(PHP 4 >= 4.3.0, PHP 5)
debug_backtrace — Erzeugt Daten zur Ablaufverfolgung
debug_backtrace() erzeugt Daten zur Ablaufverfolgung.
Legt fest, ob der "Objekt"-Index befüllt wird. Standardwert ist TRUE.
Gibt ein assoziatives Array zurück. Als zurückgegebene Arrayelemente von debug_backtrace() sind möglich:
Name | Typ | Beschreibung |
---|---|---|
function | string | Der Name der aktuell ausgeführten Funktion. Siehe auch __FUNCTION__. |
line | integer | Die aktuelle Zeilennummer. Siehe auch __LINE__. |
file | string | Der aktuelle Dateiname. Siehe auch __FILE__. |
class | string | Der aktuelle class - Name. Siehe auch __CLASS__. |
object | object | Das aktuelle Objekt. |
type | string | Der aktuelle Typ des Aufrufs. Falls der Aufruf in einer Methode erfolgte, wird "->" zurückgegeben. Falls der Aufruf aus einer statischen Funktion erfolgte, wird "::" zurückgegeben und falls der Aufruf aus einer Funktion erfolgte, wird nichts zurückgegeben. |
args | array | Falls der Aufruf aus einer Funktion erfolgte, werden hier die Funktionsargumente aufgelistet. Falls der Aufruf aus einer eingebundenen Datei erfolgte, werden die Namen der Include-Dateien angegeben. |
Version | Beschreibung |
---|---|
5.2.5 | Der optionale Parameter provide_object wurde hinzugefügt. |
5.1.1 | Aktuelles object als möglichen Rückgabewert hinzugefügt. |
Beispiel #1 debug_backtrace()-Beispiel
<?php
// Dateiname: /tmp/a.php
function a_test($str)
{
echo "\nHi: $str";
var_dump(debug_backtrace());
}
a_test('friend');
?>
<?php
// Dateiname: /tmp/b.php
include_once '/tmp/a.php';
?>
Ergebnisse beim Aufruf von /tmp/b.php:
Hi: friend array(2) { [0]=> array(4) { ["file"] => string(10) "/tmp/a.php" ["line"] => int(10) ["function"] => string(6) "a_test" ["args"]=> array(1) { [0] => &string(6) "friend" } } [1]=> array(4) { ["file"] => string(10) "/tmp/b.php" ["line"] => int(2) ["args"] => array(1) { [0] => string(10) "/tmp/a.php" } ["function"] => string(12) "include_once" } }
Here's my little updated contribution - it prints colorful output in the way I prefer. Define a helper function isRootIp() that contains an array including your IP; then calls to bt() simply return, so you can sprinkle backtraces in live sites w/o anyone knowing.
<?php
function bt()
{
if( ! isRootIp() )
{
return false;
}
array_walk( debug_backtrace(), create_function( '$a,$b', 'print "<br /><b>". basename( $a[\'file\'] ). "</b> <font color=\"red\">{$a[\'line\']}</font> <font color=\"green\">{$a[\'function\']} ()</font> -- ". dirname( $a[\'file\'] ). "/";' ) );
}
?>
I find it useful to know if a function is being called. in Java for instance you usually print a line with the functionname and arguments in the beginning of the function. I wanted to achieve the same thing in php thus i wrote the following class:
<?php
class Debug
{
private static $calls;
public static function log($message = null)
{
if(!is_array(self::$calls))
self::$calls = array();
$call = debug_backtrace(false);
$call = (isset($call[1]))?$call[1]:$call[0];
$call['message'] = $message;
array_push(self::$calls, $call);
}
}
?>
include this class before anything else
usage: Debug::log($message); at the beginning of your function.
write yourself a nice printout of the data;
One line of code to print simplest and shortest human readable backtrace:)
<?php
array_walk(debug_backtrace(),create_function('$a,$b','print "{$a[\'function\']}()(".basename($a[\'file\']).":{$a[\'line\']}); ";'));
?>
Surprisingly, no one has described one of the best uses of this: dumping a variable and showing the location. When debugging, especially a big and unfamiliar system, it's a pain remembering where I added those var dumps. Also, this way there is a separator between multiple dump calls.
<?php
function dump( $var ) {
$result = var_export( $var, true );
$loc = whereCalled();
return "\n<pre>Dump: $loc\n$result</pre>";
}
function whereCalled( $level = 1 ) {
$trace = debug_backtrace();
$file = $trace[$level]['file'];
$line = $trace[$level]['line'];
$object = $trace[$level]['object'];
if (is_object($object)) { $object = get_class($object); }
return "Where called: line $line of $object \n(in $file)";
}
?>
In addition, calling 'whereCalled()' from any function will quickly identify locations that are doing something unexpected (e.g., updating a property at the wrong time). I'm new to PHP, but have used the equivalent in Perl for years.
I use this simple but effective function so i can see which method in the child class called the current method (in the parent class).
<?php
function get_caller_method()
{
$traces = debug_backtrace();
if (isset($traces[2]))
{
return $traces[2]['function'];
}
return null;
}
?>
This can be used to show if a file is being accessed directly or being included/called from another:
<?php
if (count(debug_backtrace()) == 0){
// Do something
}
?>
Everybody seems to have their favorite use. I substitute this function for die(). It gives a message
to the user and emails me a PrettyPrint of what went wrong. $info is set by me,
and it does a special check in the database object.
<?php
// var_format
function var_format($v) // pretty-print var_export
{
return (str_replace(array("\n"," ","array"),
array("<br>"," "," <i>array</i>"),
var_export($v,true))."<br>");
}
function myDie($info)
{
$mysqlerr=strpos($info,"ERROR=You have an error in your SQL syntax");
if($mysqlerr>0)$info=substr($info,0,$mysqlerr)." mySql format error";
$out="<br>MSG='$info'<br>".var_format($_REQUEST)."<br>";
$bt=debug_backtrace();
$sp=0;
$trace="";
foreach($bt as $k=>$v)
{
extract($v);
$file=substr($file,1+strrpos($file,"/"));
if($file=="db.php")continue; // the db object
$trace.=str_repeat(" ",++$sp); //spaces(++$sp);
$trace.="file=$file, line=$line, function=$function<br>";
}
$out.="<br>".backTrace();
if(substr($info,0,4)=="XXX ") // special errrors when db is inaccessible
{
$out=str_replace("<br>","\n",$out);
$out=str_replace(" "," ",$out);
mail("me@example.com","Database Execution Error for user ".$REMOTE_ADDR,"$out");
exit("Database Access Error. Please try again later.");
}
mail("me@example.com",'Error Monitor','Execution Error',$out);
exit("DANG! An execution error in the program has been sent to the webmaster.
If you don't get an email from him soon, please call him.");
}
?>
This produces an output like this
file=badmode.php, line=5, function=backTrace
file=login.php, line=209, function=require
file=midScreen.php, line=264, function=require
file=masterindex.php, line=161, function=require
file=production2.php, line=121, function=require
file=index.php, line=16, function=require
Be carefull if you are using objects as arguments for function calls!
<?php
error_reporting(E_ALL);
function myPrint($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);
?>
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();
?>
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();
$f->base( 713 ); // will print.. ".. my call of base was: 713"
?>
Trust me, there are some reasons for why you might want to do this :)
An easy function to pull all details of the debug backtrace:
<?php
function getDebugBacktrace($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 $backtrace;
?>
Hope that helps,
Aryel
You should probably try to avoid changing any of the items in the args array. Consider this example:
----------
function a(&$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
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.
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.
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)
<?
// 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();
?>
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.
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[$i]["line"]))
echo(" line ".$bt[$i]["line"]."<br />");
echo(" function called: ".$bt[$i]["function"]);
if($bt[$i]["args"])
{
echo("<br /> args: ");
for($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 />");
}
}
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, $param4 )
{
trace( 'error in test()' );
}
test( 1.1, "param2\n", array( 1 => "a\n", "b\n" => 2 ), false );
?>
Surprizingly, debug_backtrace() cannot aquire arguments from the function that is used as the second or later argument of a function.
<?php
function a($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, $p3";
}
// This outputs:
// array ( 0 => 'First a', )
// Cannot aquire arguments
// Cannot aquire arguments
// First a, Second a, Third a
b(a("First a"), a("Second a"), a("Third a"));
?>
Another debug output. This is a short function that does not display the args (sometimes password are in arguments ...) and shows the callstack clearly in a table. In most cases i don't need more ...
<?php
function dieDebug($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!");
?>
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']))
{
$arr['line'] = '';
}
// Do something
}
?>
I use this for debugging in my object oriented systems. It allows me to output a debug/error/warning function with exact information about the location that the error was thrown, which is useful. Check it:
<?php
abstract class Debugger {
/**
* Throw a debug message.
*/
abstract function debug($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() {
$this->debugger->error("This is an error");
}
}
?>
Which produces something like:
Foo::bar: This is an error in /some/file at X
Ok as spagmoid already said, I just realized that my function has a similar bug than jlim's function.
So just add the following line:
if (is_array($bt['args']))
before line:
foreach ($bt['args'] as $a) {
This way you avoid the warning from being displayed.
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)
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);
}
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 .= ' ';
$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;
}
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) != $args_counter)
{
echo(", ");
}
else
{
echo(" ");
}
}
?></font><font color="#FF3300">)</font></font></td>
</tr>
<tr>
<td bgcolor="#5F72FA"><font color="#FFFFFF">{</font><br>
<font color="#FFFFFF"> file: <?
echo($debug_array[$tmp_counter]["file"]);?></font><br>
<font color="#FFFFFF"> line: <?
echo($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();
}
?>
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($t['args']) > 0) echo '(...)';
else echo '()';
echo "\r\n";
}
//echo '</pre>';
exit;
}
Pretty print the backtrace(). Functions are indented based on call value, and file is linked using file:// for convenience.
Enjoy, John Lim
function adodb_backtrace($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 .= ' ';
$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;
}