Introduction à l'utilisation de phpdbg pour déboguer des programmes PHP

Libérer: 2023-04-08 13:24:02
avant
2622 Les gens l'ont consulté

Introduction à l'utilisation de phpdbg pour déboguer des programmes PHP

PHPDBG est un module PHP SAPI qui peut contrôler l'environnement d'exploitation PHP sans modifier le code et sans affecter les performances

Peut être utilisé en PHP5.4 et autres utilisés dans la version précédente. PHP5.6 et supérieur intégreront en interne la fonction

Introduction à lutilisation de phpdbg pour déboguer des programmes PHP

  • débogage en une seule étape

  • Méthode de point d'arrêt flexible (méthode de classe, fonction, fichier : ligne, adresse mémoire, opcode)

  • Peut appeler directement l'évaluation de PHP

  • Vous pouvez afficher le code actuellement exécuté

  • API de l'espace utilisateur (espace utilisateur/espace utilisateur)

  • Intégration pratique

  • Prise en charge du fichier de configuration PHP spécifié

  • Variables globales JIT

  • prise en charge de readline (peut sélectionner), terminal le fonctionnement est plus pratique

  • Débogage à distance, à l'aide de l'interface graphique Java

  • Facile à utiliser (voir l'aide pour plus de détails)

Installer

S'il s'agit de PHP56

cd /usr/src/php-src/sapi
git clone https://github.com/krakjoe/phpdbg
cd ../
./buildconf --force
./config.nice
make -j8
make install-phpdbg
Copier après la connexion

S'il s'agit de PHP56, activez simplement phpdbg directement

Remarque : vous pouvez le faire dans la configuration php, activez --with-readline pour que phpdbg prenne en charge l'historique, la saisie semi-automatique, la liste des onglets, etc.

phpdbginit

Configuration automatique de votre session de débogage

phpdbg -imy.phpdbginit
Copier après la connexion

De plus, .phpdbginit peut contenir du code embarqué, permettant par exemple

  • la mise en place de la complétion automatique

  • l'enregistrement de fonctions

  • l'acquisition et la pré-compilation de code

  • le démarrage d'une application web

Le .phpdbginit par défaut

##########################################################
# .phpdbginit
#
# Lines starting with # are ignored
# Code must start and end with <: and :> respectively
##########################################################
# Place initialization commands one per line
##########################################################
# exec sapi/phpdbg/test.php
 
##########################################################
# Embedding code in .phpdbginit
##########################################################
<:
/*
 If readline is loaded, you might want to setup completion:
*/
if (function_exists(&#39;readline_completion_function&#39;)) {
    readline_completion_function(function(){
        return array_merge(
            get_defined_functions()[&#39;user&#39;],
            array_keys(get_defined_constants())
        );
    });
}
:>
##########################################################
# Now carry on initializing phpdbg ...
##########################################################
# R my_debugging_function
 
##########################################################
# PHP has many functions that might be useful
# ... you choose ...
##########################################################
# R touch
# R unlink
# R scandir
# R glob
 
##########################################################
# Remember: *you have access to the shell*
##########################################################
# The output of registered function calls is not,
# by default, very pretty (unless you implement
# and register a new implementation for phpdbg)
# The output of shell commands will usually be more
# readable on the console
##########################################################
# TLDR; if you have a good shell, use it ...
########################################################## 
Copier après la connexion

Afficher le numéro de version

[root@localhost ~]# php -v
PHP 5.6.16 (cli) (built: Dec  8 2015 09:10:23) (DEBUG)
Copyright (c) 1997-2015 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2015 Zend Technologies
    with Xdebug v2.3.3, Copyright (c) 2002-2015, by Derick Rethans
[root@localhost ~]# phpdbg -V
phpdbg 0.4.0 (built: Dec  8 2015 09:10:43)
PHP 5.6.16, Copyright (c) 1997-2015 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2015 Zend Technologies
    with Xdebug v2.3.3, Copyright (c) 2002-2015, by Derick Rethans
Copier après la connexion

Afficher l'aide

[root@localhost ~]# phpdbg
[Welcome to phpdbg, the interactive PHP debugger, v0.4.0]
To get help using phpdbg type "help" and press enter
[Please report bugs to <http://github.com/krakjoe/phpdbg/issues>]
phpdbg> help
 
phpdbg is a lightweight, powerful and easy to use debugging platform for PHP5.4+
It supports the following commands:
 
Information
  list     list PHP source
  info     displays information on the debug session
  print    show opcodes
  frame    select a stack frame and print a stack frame summary
  back     shows the current backtrace
  help     provide help on a topic
 
Starting and Stopping Execution
  exec     set execution context
  run      attempt execution
  step     continue execution until other line is reached
  continue continue execution
  until    continue execution up to the given location
  finish   continue up to end of the current execution frame
  leave    continue up to end of the current execution frame and halt after the calling instruction
  break    set a breakpoint at the specified target
  watch    set a watchpoint on $variable
  clear    clear one or all breakpoints
  clean    clean the execution environment
 
Miscellaneous
  set      set the phpdbg configuration
  source   execute a phpdbginit script
  register register a phpdbginit function as a command alias
  sh       shell a command
  ev       evaluate some code
  quit     exit phpdbg
 
Type help <command> or (help alias) to get detailed help on any of the above commands, for example help list or h l.  Note that help will also match partial commands if unique (and list
out options if not unique), so help clea will give help on the clean command, but help cl will list the summary for clean and clear.
 
Type help aliases to show a full alias list, including any registered phpdginit functions
Type help syntax for a general introduction to the command syntax.
Type help options for a list of phpdbg command line options.
Type help phpdbginit to show how to customise the debugger environment.
phpdbg> help list
Command: list  Alias: l  lists some code
 
The list command displays source code for the given argument.  The target type is specficied by a second subcommand keyword:
 
  Type     Alias  Purpose
  lines    l      List N lines from the current execution point
  func     f      List the complete source for a specified function
  method   m      List the complete source for a specified class::method
  class    c      List the complete source for a specified class
 
Note that the context of lines, func and method can be determined by parsing the argument, so these subcommands are optional.  However, you must specify the class keyword to list off a
class.
 
Examples
 
    phpdbg>  list 2
    phpdbg>  l l 2
    List the next 2 lines from the current file
 
    phpdbg>  list my_function
    phpdbg>  l f my_function
    List the source of the function my_function
 
    phpdbg>  list func .mine
    phpdbg>  l f .mine
    List the source of the method mine from the active class in scope
 
    phpdbg>  list m my::method
    phpdbg>  l my::method
    List the source of my::method
 
    phpdbg>  list c myClass
    phpdbg>  l c myClass
    List the source of myClass
 
Note that functions and classes can only be listed if the corresponding classes and functions table in the Zend executor has a corresponding entry.  You can use the compile command to
populate these tables for a given execution context.
phpdbg> help break
Command: break  Alias: b  set breakpoint
 
Breakpoints can be set at a range of targets within the execution environment.  Execution will be paused if the program flow hits a breakpoint.  The break target can be one of the
following types:
 
  Target   Alias Purpose
  at       A     specify breakpoint by location and condition
  del      d     delete breakpoint by breakpoint identifier number
 
Break at takes two arguments. The first is any valid target. The second is a valid PHP expression which will trigger the break in execution, if evaluated as true in a boolean context at
the specified target.
 
Note that breakpoints can also be disabled and re-enabled by the set break command.
 
Examples
 
    phpdbg>  break test.php:100
    phpdbg>  b test.php:100
    Break execution at line 100 of test.php
 
    phpdbg>  break 200
    phpdbg>  b 200
    Break execution at line 200 of the currently PHP script file
 
    phpdbg>  break \mynamespace\my_function
    phpdbg>  b \mynamespace\my_function
    Break execution on entry to \mynamespace\my_function
 
    phpdbg>  break classX::method
    phpdbg>  b classX::method
    Break execution on entry to classX::method
 
    phpdbg>  break 0x7ff68f570e08
    phpdbg>  b 0x7ff68f570e08
    Break at the opline at the address 0x7ff68f570e08
 
    phpdbg>  break my_function#14
    phpdbg>  b my_function#14
    Break at the opline #14 of the function my_function
 
    phpdbg>  break \my\class::method#2
    phpdbg>  b \my\class::method#2
    Break at the opline #2 of the method \my\class::method
 
    phpdbg>  break test.php:#3
    phpdbg>  b test.php:#3
    Break at opline #3 in test.php
 
    phpdbg>  break if $cnt > 10
    phpdbg>  b if $cnt > 10
    Break when the condition ($cnt > 10) evaluates to true
 
    phpdbg>  break at phpdbg::isGreat if $opt == &#39;S&#39;
    phpdbg>  break @ phpdbg::isGreat if $opt == &#39;S&#39;
    Break at any opcode in phpdbg::isGreat when the condition ($opt == &#39;S&#39;) is true
 
    phpdbg>  break at test.php:20 if !isset($x)
    Break at every opcode on line 20 of test.php when the condition evaluates to true
 
    phpdbg>  break ZEND_ADD
    phpdbg>  b ZEND_ADD
    Break on any occurence of the opcode ZEND_ADD
 
    phpdbg>  break del 2
    phpdbg>  b ~ 2
    Remove breakpoint 2
 
Note: Conditional breaks are costly in terms of runtime overhead. Use them only when required as they significantly slow execution.
 
Note: An address is only valid for the current compilation.
phpdbg> help watch
Command: watch  Alias: w  set watchpoint
 
Sets watchpoints on variables as long as they are defined
Passing no parameter to watch, lists all actually active watchpoints
 
Format for $variable
 
   $var      Variable $var
   $var[]    All array elements of $var
   $var->    All properties of $var
   $var->a   Property $var->a
   $var[b]   Array element with key b in array $var
 
Subcommands of watch:
 
   Type     Alias      Purpose
   array       a       Sets watchpoint on array/object to observe if an entry is added or removed
   recursive   r       Watches variable recursively and automatically adds watchpoints if some entry is added to an array/object
   delete      d       Removes watchpoint
 
Note when recursive watchpoints are removed, watchpoints on all the children are removed too
 
Examples
 
     phpdbg>  watch
     List currently active watchpoints
 
     phpdbg>  watch $array
     phpdbg>  w $array
     Set watchpoint on $array
 
     phpdbg>  watch recursive $obj->
     phpdbg>  w r $obj->
     Set recursive watchpoint on $obj->
 
     phpdbg>  watch delete $obj->a
     phpdbg>  w d $obj->a
     Remove watchpoint $obj->a
 
Technical note: If using this feature with a debugger, you will get many segmentation faults, each time when a memory page containing a watched address is hit.
                You then you can continue, phpdbg will remove the write protection, so that the program can continue.
                If phpdbg could not handle that segfault, the same segfault is triggered again and this time phpdbg will abort.
Copier après la connexion

Ces documents d'aide suffisent

Pourquoi les sorties des exemples de codes testb et testa sont-elles comme ça ?

<?php
 
ini_set("memory_limit","-1");
 
class test{
 
    public function testa(){
 
        $a=1;
        $b = &$a;
        return 0 + (++$a) + (++$a);
 
    }
 
    public function testb(){
 
        $a=1;
        $b = &$a;
        return ++$a  + (++$a);
 
    }
 
    public function convert($size)
    {
        $unit=array(&#39;b&#39;,&#39;kb&#39;,&#39;mb&#39;,&#39;gb&#39;,&#39;tb&#39;,&#39;pb&#39;);
        return @round($size/pow(1024,($i=floor(log($size,1024)))),2).&#39; &#39;.$unit[$i];
    }
 
    public function allsort($arr){
        sort($arr);
        $len = count($arr)-1;
        $rs = array();
        $rs[] = $arr;
        $x = $len;
 
        while($x > 0){
            $y = $x --;
            if($arr[$x] < $arr[$y]){
                $z = $len;
                while($arr[$x] > $arr[$z]){
                    $z--;
                }
                list($arr[$x],$arr[$z]) = array($arr[$z],$arr[$x]);
 
                for($i=$len;$i>$y;$i--,$y++){
                    list($arr[$i],$arr[$y]) = array($arr[$y],$arr[$i]);
                }
                $x = $len;
                $rs[] = $arr;
            }
 
        }
        return $rs;
    }
}
 
$s = new test();
$resa = $s->testa();
$resb = $s->testb();
$resc = $s->allsort([1,2,3]);
echo $resa,"\n",$resb,"\n";
#print_r($resb);
Copier après la connexion

Démarrer le débogage

[root@localhost ~]# phpdbg -e kk.php
[Welcome to phpdbg, the interactive PHP debugger, v0.4.0]
To get help using phpdbg type "help" and press enter
[Please report bugs to <http://github.com/krakjoe/phpdbg/issues>]
[Attempting compilation of /root/kk.php]
[Success]
Copier après la connexion

Afficher quelques opcodes de la classe actuelle

phpdbg> p c test
[User Class: test]
Methods (4):
        L7-13 test::testa() /root/kk.php
                L7      0xb77b553c ZEND_EXT_NOP                   <unused>             <unused>             <unused>           
                L9      0xb77b5558 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L9      0xb77b5574 ZEND_ASSIGN                    $a                   C0                   @0                 
                L10     0xb77b5590 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L10     0xb77b55ac ZEND_ASSIGN_REF                $b                   $a                   @1                 
                L11     0xb77b55c8 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L11     0xb77b55e4 ZEND_PRE_INC                   $a                   <unused>             @2                 
                L11     0xb77b5600 ZEND_ADD                       C1                   @2                   @3                 
                L11     0xb77b561c ZEND_PRE_INC                   $a                   <unused>             @4                 
                L11     0xb77b5638 ZEND_ADD                       @3                   @4                   @5                 
                L11     0xb77b5654 ZEND_RETURN                    @5                   <unused>             <unused>           
                L13     0xb77b5670 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L13     0xb77b568c ZEND_RETURN                    C2                   <unused>             <unused>           
        L15-21 test::testb() /root/kk.php
                L15     0xb77b656c ZEND_EXT_NOP                   <unused>             <unused>             <unused>           
                L17     0xb77b6588 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L17     0xb77b65a4 ZEND_ASSIGN                    $a                   C0                   @0                 
                L18     0xb77b65c0 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L18     0xb77b65dc ZEND_ASSIGN_REF                $b                   $a                   @1                 
                L19     0xb77b65f8 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L19     0xb77b6614 ZEND_PRE_INC                   $a                   <unused>             @2                 
                L19     0xb77b6630 ZEND_PRE_INC                   $a                   <unused>             @3                 
                L19     0xb77b664c ZEND_ADD                       @2                   @3                   @4                 
                L19     0xb77b6668 ZEND_RETURN                    @4                   <unused>             <unused>           
                L21     0xb77b6684 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L21     0xb77b66a0 ZEND_RETURN                    C1                   <unused>             <unused>           
        L23-27 test::convert() /root/kk.php
                L23     0xb77b66ec ZEND_EXT_NOP                   <unused>             <unused>             <unused>           
                L23     0xb77b6708 ZEND_RECV                      <unused>             <unused>             $size              
                L25     0xb77b6724 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L25     0xb77b6740 ZEND_INIT_ARRAY                C0                   <unused>             @0                 
                L25     0xb77b675c ZEND_ADD_ARRAY_ELEMENT         C1                   <unused>             @0                 
                L25     0xb77b6778 ZEND_ADD_ARRAY_ELEMENT         C2                   <unused>             @0                 
                L25     0xb77b6794 ZEND_ADD_ARRAY_ELEMENT         C3                   <unused>             @0                 
                L25     0xb77b67b0 ZEND_ADD_ARRAY_ELEMENT         C4                   <unused>             @0                 
                L25     0xb77b67cc ZEND_ADD_ARRAY_ELEMENT         C5                   <unused>             @0                 
                L25     0xb77b67e8 ZEND_ASSIGN                    $unit                @0                   @1                 
                L26     0xb77b6804 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L26     0xb77b6820 ZEND_BEGIN_SILENCE             <unused>             <unused>             @2                 
                L26     0xb77b683c ZEND_EXT_FCALL_BEGIN           <unused>             <unused>             <unused>           
                L26     0xb77b6858 ZEND_EXT_FCALL_BEGIN           <unused>             <unused>             <unused>           
                L26     0xb77b6874 ZEND_SEND_VAL                  C6                   <unused>             <unused>           
                L26     0xb77b6890 ZEND_EXT_FCALL_BEGIN           <unused>             <unused>             <unused>           
                L26     0xb77b68ac ZEND_EXT_FCALL_BEGIN           <unused>             <unused>             <unused>           
                L26     0xb77b68c8 ZEND_SEND_VAR                  $size                <unused>             <unused>           
                L26     0xb77b68e4 ZEND_SEND_VAL                  C7                   <unused>             <unused>           
                L26     0xb77b6900 ZEND_DO_FCALL                  C8                   <unused>             @3                 
                L26     0xb77b691c ZEND_EXT_FCALL_END             <unused>             <unused>             <unused>           
                L26     0xb77b6938 ZEND_SEND_VAR_NO_REF           @3                   <unused>             <unused>           
                L26     0xb77b6954 ZEND_DO_FCALL                  C9                   <unused>             @4                 
                L26     0xb77b6970 ZEND_EXT_FCALL_END             <unused>             <unused>             <unused>           
                L26     0xb77b698c ZEND_ASSIGN                    $i                   @4                   @5                 
                L26     0xb77b69a8 ZEND_SEND_VAR_NO_REF           @5                   <unused>             <unused>           
                L26     0xb77b69c4 ZEND_DO_FCALL                  C10                  <unused>             @6                 
                L26     0xb77b69e0 ZEND_EXT_FCALL_END             <unused>             <unused>             <unused>           
                L26     0xb77b69fc ZEND_DIV                       $size                @6                   @7                 
                L26     0xb77b6a18 ZEND_SEND_VAL                  @7                   <unused>             <unused>           
                L26     0xb77b6a34 ZEND_SEND_VAL                  C11                  <unused>             <unused>           
                L26     0xb77b6a50 ZEND_DO_FCALL                  C12                  <unused>             @8                 
                L26     0xb77b6a6c ZEND_EXT_FCALL_END             <unused>             <unused>             <unused>           
                L26     0xb77b6a88 ZEND_END_SILENCE               @2                   <unused>             <unused>           
                L26     0xb77b6aa4 ZEND_CONCAT                    @8                   C13                  @9                 
                L26     0xb77b6ac0 ZEND_FETCH_DIM_R               $unit                $i                   @10                
                L26     0xb77b6adc ZEND_CONCAT                    @9                   @10                  @11                
                L26     0xb77b6af8 ZEND_RETURN                    @11                  <unused>             <unused>           
                L27     0xb77b6b14 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L27     0xb77b6b30 ZEND_RETURN                    C14                  <unused>             <unused>           
        L29-54 test::allsort() /root/kk.php
                L29     0xb77b818c ZEND_EXT_NOP                   <unused>             <unused>             <unused>           
                L29     0xb77b81a8 ZEND_RECV                      <unused>             <unused>             $arr               
                L30     0xb77b81c4 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L30     0xb77b81e0 ZEND_EXT_FCALL_BEGIN           <unused>             <unused>             <unused>           
                L30     0xb77b81fc ZEND_SEND_REF                  $arr                 <unused>             <unused>           
                L30     0xb77b8218 ZEND_DO_FCALL                  C0                   <unused>             @0                 
                L30     0xb77b8234 ZEND_EXT_FCALL_END             <unused>             <unused>             <unused>           
                L31     0xb77b8250 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L31     0xb77b826c ZEND_EXT_FCALL_BEGIN           <unused>             <unused>             <unused>           
                L31     0xb77b8288 ZEND_SEND_VAR                  $arr                 <unused>             <unused>           
                L31     0xb77b82a4 ZEND_DO_FCALL                  C1                   <unused>             @1                 
                L31     0xb77b82c0 ZEND_EXT_FCALL_END             <unused>             <unused>             <unused>           
                L31     0xb77b82dc ZEND_SUB                       @1                   C2                   @2                 
                L31     0xb77b82f8 ZEND_ASSIGN                    $len                 @2                   @3                 
                L32     0xb77b8314 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L32     0xb77b8330 ZEND_INIT_ARRAY                <unused>             <unused>             @4                 
                L32     0xb77b834c ZEND_ASSIGN                    $rs                  @4                   @5                 
                L33     0xb77b8368 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L33     0xb77b8384 ZEND_ASSIGN_DIM                $rs                  <unused>             @6                 
                L33     0xb77b83a0 UNKNOWN                        $arr                 @7                   <unused>           
                L34     0xb77b83bc ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L34     0xb77b83d8 ZEND_ASSIGN                    $x                   $len                 @8                 
                L36     0xb77b83f4 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L36     0xb77b8410 ZEND_IS_SMALLER                C3                   $x                   @9                 
                L36     0xb77b842c ZEND_JMPZ                      @9                   J86                  <unused>           
                L37     0xb77b8448 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L37     0xb77b8464 ZEND_POST_DEC                  $x                   <unused>             @10                
                L37     0xb77b8480 ZEND_ASSIGN                    $y                   @10                  @11                
                L38     0xb77b849c ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L38     0xb77b84b8 ZEND_FETCH_DIM_R               $arr                 $x                   @12                
                L38     0xb77b84d4 ZEND_FETCH_DIM_R               $arr                 $y                   @13                
                L38     0xb77b84f0 ZEND_IS_SMALLER                @12                  @13                  @14                
                L38     0xb77b850c ZEND_JMPZ                      @14                  J85                  <unused>           
                L39     0xb77b8528 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L39     0xb77b8544 ZEND_ASSIGN                    $z                   $len                 @15                
                L40     0xb77b8560 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L40     0xb77b857c ZEND_FETCH_DIM_R               $arr                 $x                   @16                
                L40     0xb77b8598 ZEND_FETCH_DIM_R               $arr                 $z                   @17                
                L40     0xb77b85b4 ZEND_IS_SMALLER                @17                  @16                  @18                
                L40     0xb77b85d0 ZEND_JMPZ                      @18                  J44                  <unused>           
                L41     0xb77b85ec ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L41     0xb77b8608 ZEND_POST_DEC                  $z                   <unused>             @19                
                L41     0xb77b8624 ZEND_FREE                      @19                  <unused>             <unused>           
                L42     0xb77b8640 ZEND_JMP                       J36                                                          
                L43     0xb77b865c ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L43     0xb77b8678 ZEND_FETCH_DIM_R               $arr                 $z                   @20                
                L43     0xb77b8694 ZEND_INIT_ARRAY                @20                  <unused>             @21                
                L43     0xb77b86b0 ZEND_FETCH_DIM_R               $arr                 $x                   @22                
                L43     0xb77b86cc ZEND_ADD_ARRAY_ELEMENT         @22                  <unused>             @21                
                L43     0xb77b86e8 ZEND_FETCH_DIM_TMP_VAR         @21                  C4                   @23                
                L43     0xb77b8704 ZEND_ASSIGN_DIM                $arr                 $z                   @24                
                L43     0xb77b8720 UNKNOWN                        @23                  @25                  <unused>           
                L43     0xb77b873c ZEND_FETCH_DIM_TMP_VAR         @21                  C5                   @26                
                L43     0xb77b8758 ZEND_ASSIGN_DIM                $arr                 $x                   @27                
                L43     0xb77b8774 UNKNOWN                        @26                  @28                  <unused>           
                L43     0xb77b8790 ZEND_FREE                      @21                  <unused>             <unused>           
                L45     0xb77b87ac ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L45     0xb77b87c8 ZEND_ASSIGN                    $i                   $len                 @29                
                L45     0xb77b87e4 ZEND_IS_SMALLER                $y                   $i                   @30                
                L45     0xb77b8800 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L45     0xb77b881c ZEND_JMPZNZ                    @30                  J79 or J66           <unused>           
                L45     0xb77b8838 ZEND_POST_DEC                  $i                   <unused>             @31                
                L45     0xb77b8854 ZEND_FREE                      @31                  <unused>             <unused>           
                L45     0xb77b8870 ZEND_POST_INC                  $y                   <unused>             @32                
                L45     0xb77b888c ZEND_FREE                      @32                  <unused>             <unused>           
                L45     0xb77b88a8 ZEND_JMP                       J58                                                          
                L46     0xb77b88c4 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L46     0xb77b88e0 ZEND_FETCH_DIM_R               $arr                 $y                   @33                
                L46     0xb77b88fc ZEND_INIT_ARRAY                @33                  <unused>             @34                
                L46     0xb77b8918 ZEND_FETCH_DIM_R               $arr                 $i                   @35                
                L46     0xb77b8934 ZEND_ADD_ARRAY_ELEMENT         @35                  <unused>             @34                
                L46     0xb77b8950 ZEND_FETCH_DIM_TMP_VAR         @34                  C6                   @36                
                L46     0xb77b896c ZEND_ASSIGN_DIM                $arr                 $y                   @37                
                L46     0xb77b8988 UNKNOWN                        @36                  @38                  <unused>           
                L46     0xb77b89a4 ZEND_FETCH_DIM_TMP_VAR         @34                  C7                   @39                
                L46     0xb77b89c0 ZEND_ASSIGN_DIM                $arr                 $i                   @40                
                L46     0xb77b89dc UNKNOWN                        @39                  @41                  <unused>           
                L46     0xb77b89f8 ZEND_FREE                      @34                  <unused>             <unused>           
                L47     0xb77b8a14 ZEND_JMP                       J61                                                          
                L48     0xb77b8a30 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L48     0xb77b8a4c ZEND_ASSIGN                    $x                   $len                 @42                
                L49     0xb77b8a68 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L49     0xb77b8a84 ZEND_ASSIGN_DIM                $rs                  <unused>             @43                
                L49     0xb77b8aa0 UNKNOWN                        $arr                 @44                  <unused>           
                L50     0xb77b8abc ZEND_JMP                       J85                                                          
                L52     0xb77b8ad8 ZEND_JMP                       J23                                                          
                L53     0xb77b8af4 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L53     0xb77b8b10 ZEND_RETURN                    $rs                  <unused>             <unused>           
                L54     0xb77b8b2c ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L54     0xb77b8b48 ZEND_RETURN                    C8                   <unused>             <unused>           
phpdbg>
Copier après la connexion

Ajouter des points d'arrêt et démarrer le débogage

phpdbg> b test::testa
[Breakpoint #0 added at test::testa]
phpdbg> b test::testb
[Breakpoint #1 added at test::testb]
phpdbg> b 0xb77b6614
[Breakpoint #2 added at 0xb77b6614]
phpdbg> b 0xb77b6630
[Breakpoint #3 added at 0xb77b6630]
Copier après la connexion

Exécuter et afficher le code

phpdbg> r
[Breakpoint #0 in test::testa() at /root/kk.php:7, hits: 1]
 00006:
>00007:         public function testa(){
 00008:
 00009:                 $a=1;
phpdbg> l test::testa
00007:  public function testa(){
00008:
00009:          $a=1;
00010:          $b = &$a;
00011:          return 0 + (++$a) + (++$a);
00012:
00013:  }
00014:
phpdbg> p s
[Stack in test::testa()]
        L7-13 test::testa() /root/kk.php
                L7      0xb77b553c ZEND_EXT_NOP                   <unused>             <unused>             <unused>           
                L9      0xb77b5558 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L9      0xb77b5574 ZEND_ASSIGN                    $a                   C0                   @0                 
                L10     0xb77b5590 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L10     0xb77b55ac ZEND_ASSIGN_REF                $b                   $a                   @1                 
                L11     0xb77b55c8 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L11     0xb77b55e4 ZEND_PRE_INC                   $a                   <unused>             @2                 
                L11     0xb77b5600 ZEND_ADD                       C1                   @2                   @3                 
                L11     0xb77b561c ZEND_PRE_INC                   $a                   <unused>             @4                 
                L11     0xb77b5638 ZEND_ADD                       @3                   @4                   @5                 
                L11     0xb77b5654 ZEND_RETURN                    @5                   <unused>             <unused>           
                L13     0xb77b5670 ZEND_EXT_STMT                  <unused>             <unused>             <unused>           
                L13     0xb77b568c ZEND_RETURN                    C2                   <unused>             <unused>   <br><br>
Copier après la connexion

Continuer l'exécution

Comme gdb, la commande continue d'exécution de phpdbg est également continue, l'abréviation est c

Afficher les points d'arrêt

phpdbg> info b
------------------------------------------------
Method Breakpoints:
#0              test::testa
#1              test::testb
------------------------------------------------
Opline Breakpoints:
#2              0xb77b6614
#3              0xb77b6630
Copier après la connexion

opération d'évaluation

Peut exécuter n'importe quel code PHP

Nous pouvons voir la différence entre testa et testb dans l'exemple ci-dessus

L7-13 test::testa() /root/kk.php
        L11     0xb77b55e4 ZEND_PRE_INC                   $a                   <unused>             @2
        L11     0xb77b5600 ZEND_ADD                       C1                   @2                   @3
        L11     0xb77b561c ZEND_PRE_INC                   $a                   <unused>             @4
        L11     0xb77b5638 ZEND_ADD                       @3                   @4                   @5
L15-21 test::testb() /root/kk.php
        L19     0xb77b6614 ZEND_PRE_INC                   $a                   <unused>             @2
        L19     0xb77b6630 ZEND_PRE_INC                   $a                   <unused>             @3
        L19     0xb77b664c ZEND_ADD                       @2                   @3                   @4
Copier après la connexion

La différence est que ZEND_PRE_INC cet opcode est différent, cet opcode est ++$a

Lorsque la référence existe dans testb, $a est d'abord incrémenté deux fois puis ajouté, donc le résultat est 6. Cela devrait être un problème avec PHP lui-même

Cet outil est beaucoup plus riche que. vld. PHP deviendra de plus en plus puissant.

Recommandations associées :

Tutoriel vidéo PHP : https://www.php.cn/course/list/29/type/2.html

Ce qui précède est le contenu détaillé de. pour plus d'informations, suivez d'autres articles connexes sur le site Web de PHP en chinois!

Étiquettes associées:
php
source:cnblogs.com
Déclaration de ce site Web
Le contenu de cet article est volontairement contribué par les internautes et les droits d'auteur appartiennent à l'auteur original. Ce site n'assume aucune responsabilité légale correspondante. Si vous trouvez un contenu suspecté de plagiat ou de contrefaçon, veuillez contacter admin@php.cn
Tutoriels populaires
Plus>
Derniers téléchargements
Plus>
effets Web
Code source du site Web
Matériel du site Web
Modèle frontal