Commit: 49dd23a4a88040cf1134c374b2369a104f803765
Author: Peter Kokot <[email protected]> Wed, 22 May 2019 04:43:45
+0200
Parents: 35a1baa22f5a5388194047182e3eca31371c6b40
Branches: master
Link:
http://git.php.net/?p=web/bugs.git;a=commitdiff;h=49dd23a4a88040cf1134c374b2369a104f803765
Log:
Move backtrace pages to templates
Changed paths:
M include/functions.php
A templates/pages/bugs_generating_backtrace.php
A templates/pages/bugs_generating_backtrace_win32.php
M www/bugs-generating-backtrace-win32.php
M www/bugs-generating-backtrace.php
diff --git a/include/functions.php b/include/functions.php
index 5e314a2..fd3bbd7 100644
--- a/include/functions.php
+++ b/include/functions.php
@@ -1707,32 +1707,6 @@ function inline_content_menu($base_url, $current_action,
array $menu)
echo "</p>\n";
}
-/**
- * Inline content menu for backtraces
- *
- * Specify either 'Unix' or 'Windows' to select the current page
- */
-function backtrace_inline_menu($platform)
-{
- if ($platform != 'Unix' && $platform != 'Windows') {
- return;
- }
-
- $buffer = '';
-
- foreach (['Unix' => '', 'Windows' => '-win32'] as $platform_key =>
$platform_suffix) {
- if ($platform_key == $platform) {
- $buffer .= sprintf('<strong>%s</strong> | ', $platform_key);
- } else {
- $buffer .= sprintf('<a
href="/bugs-generating-backtrace%s.php">%s</a> | ', $platform_suffix,
$platform_key);
- }
- }
-
- echo "<p>";
- echo rtrim($buffer, ' | ');
- echo "</p>\n";
-}
-
function admin_table_static(array $header, array $rows)
{
if (!$header || !$rows || sizeof($header) != sizeof($rows[0])) {
diff --git a/templates/pages/bugs_generating_backtrace.php
b/templates/pages/bugs_generating_backtrace.php
new file mode 100644
index 0000000..b99f383
--- /dev/null
+++ b/templates/pages/bugs_generating_backtrace.php
@@ -0,0 +1,179 @@
+<?php $this->extends('layout.php', ['title' => 'Generating a gdb backtrace'])
?>
+
+<?php $this->start('content') ?>
+
+<p>
+<strong>Unix</strong> | <a
href="/bugs-generating-backtrace-win32.php">Windows</a>
+</p>
+
+<h1>Generating a gdb backtrace</h1>
+
+<h3>Noticing PHP crashes</h3>
+
+There's no absolute way to know that PHP is crashing, but there may be signs.
+Typically, if you access a page that is always supposed to generate output (has
+a leading HTML block, for example), and suddenly get "Document contains no
data"
+from your browser, it may mean that PHP crashes somewhere along the execution
of
+the script. Another way to tell that PHP is crashing is by looking at the
Apache
+error logs, and looking for SEGV (Apache 1.2) or Segmentation Fault (Apache
+1.3).
+
+<h3>Important!</h3>
+To get a backtrace with correct information you must have PHP configured with
+<code>--enable-debug</code>!
+
+<h3>If you don't have a core file yet:</h3>
+
+<ul>
+ <li>
+ Remove any limits you may have on core dump size from your shell:
+ <ul>
+ <li>tcsh: unlimit coredumpsize</li>
+ <li>bash/sh: ulimit -c unlimited</li>
+ </ul>
+ </li>
+ <li>
+ Ensure that the directory in which you're running PHP, or the
+ PHP-enabled httpd, has write permissions for the user who's running
PHP.
+ </li>
+ <li>
+ Cause PHP to crash:
+ <ul>
+ <li>PHP CGI: Simply run php with the script that crashes it</li>
+ <li>PHP Apache Module: Run httpd -X, and access the script that
crashes PHP</li>
+ </ul>
+ </li>
+</ul>
+
+<h3>Generic way to get a core on Linux</h3>
+
+<ul>
+ <li>
+ Set up the core pattern (run this command as <i>root</i>):
+ <ul>
+ <li>echo "<cores dir>/core-%e.%p" >
/proc/sys/kernel/core_pattern</li>
+ <li>make sure the directory is writable by PHP</li>
+ </ul>
+ </li>
+ <li>Set the ulimit (see above how to do it).</li>
+ <li>Restart/rerun PHP.</li>
+</ul>
+
+<p>After that any process crashing in your system, including PHP, will leave
its
+core file in the directory you've specified in <i>core_pattern</i>.</p>
+
+<h3>Once you have the core file:</h3>
+
+<ul>
+ <li>
+ Run gdb with the path to the PHP or PHP-enabled httpd binary, and path
+ to the core file. Some examples:
+ <ul>
+ <li><code>gdb /usr/local/apache/sbin/httpd
/usr/local/apache/sbin/core</code></li>
+ <li><code>gdb /home/user/dev/php-snaps/sapi/cli/php
/home/user/dev/testing/core</code></li>
+ </ul>
+ </li>
+ <li>
+ At the gdb prompt, run:
+ <ul>
+ <li><code>(gdb) bt</code></li>
+ </ul>
+ </li>
+</ul>
+
+<h3>If you can't get a core file:</h3>
+<ul>
+ <li>
+ Run httpd -X under gdb with something like:
+ <ul>
+ <li><code>gdb /usr/local/apache/sbin/httpd</code></li>
+ <li>(gdb) run -X</li>
+ </ul>
+ </li>
+ <li>
+ Then use your web browser and access your server to force the crash.
You
+ should see a gdb prompt appear and some message indicating that there
+ was a crash. At this gdb prompt, type:
+ <ul>
+ <li><code>(gdb) bt</code></li>
+ </ul>
+ <ul>
+ <li>
+ or, running from the commandline
+ <ul>
+ <li>
+ gdb /home/user/dev/php-snaps/sapi/cli/php
+ <ul>
+ <li><code>(gdb) run /path/to/script.php</code></li>
+ <li><code>(gdb) bt</code></li>
+ </ul>
+ </li>
+ </ul>
+ </li>
+ </ul>
+ </li>
+</ul>
+
+<p>This should generate a backtrace, that you should submit in the bug report,
+along with any other details you can give us about your setup, and offending
+script.</p>
+
+<h3>Locating which function call caused a segfault:</h3>
+
+<p>You can locate the function call that caused a segfault, easily, with gdb.
+First, you need a core file or to generate a segfault under gdb as described
+above.</p>
+
+<p>In PHP, each function is executed by an internal function called
+<b><code>execute()</code></b> and has its own stack. Each line generated by the
+<b><code>bt</code></b> command represents a function call stack. Typically, you
+will see several <b><code>execute()</code></b> lines when you issue
+<b><code>bt</code></b>. You are interested in the last
+<b><code>execute()</code></b> stack (i.e. smallest frame number). You can move
+the current working stack with the <b><code>up</code></b>, <code>down</code> or
+<b><code>frame</code></b> commands. Below is an example gdb session that can be
+used as a guideline on how to handle your segfault.</p>
+
+<ul>
+ <li>Sample gdb session</li>
+ <pre><code>
+(gdb) bt
+#0 0x080ca21b in _efree (ptr=0xbfffdb9b) at zend_alloc.c:240
+#1 0x080d691a in _zval_dtor (zvalue=0x8186b94) at zend_variables.c:44
+#2 0x080cfab3 in _zval_ptr_dtor (zval_ptr=0xbfffdbfc) at
zend_execute_API.c:274
+#3 0x080f1cc4 in execute (op_array=0x816c670) at ./zend_execute.c:1605
+#4 0x080f1e06 in execute (op_array=0x816c530) at ./zend_execute.c:1638
+#5 0x080f1e06 in execute (op_array=0x816c278) at ./zend_execute.c:1638
+#6 0x080f1e06 in execute (op_array=0x8166eec) at ./zend_execute.c:1638
+#7 0x080d7b93 in zend_execute_scripts (type=8, retval=0x0, file_count=3) at
zend.c:810
+#8 0x0805ea75 in php_execute_script (primary_file=0xbffff650) at main.c:1310
+#9 0x0805cdb3 in main (argc=2, argv=0xbffff6fc) at cgi_main.c:753
+#10 0x400c91be in __libc_start_main (main=0x805c580 <main>, argc=2,
ubp_av=0xbffff6fc,
+ init=0x805b080 <_init>, fini=0x80f67b4 <_fini>,
rtld_fini=0x4000ddd0 <_dl_fini>,
+ stack_end=0xbffff6ec) at ../sysdeps/generic/libc-start.c:129
+(gdb) frame 3
+#3 0x080f1cc4 in execute (op_array=0x816c670) at ./zend_execute.c:1605
+(gdb) print (char
*)(executor_globals.function_state_ptr->function)->common.function_name
+$14 = 0x80fa6fa "pg_result_error"
+(gdb) print (char *)executor_globals.active_op_array->function_name
+$15 = 0x816cfc4 "result_error"
+(gdb) print (char *)executor_globals.active_op_array->filename
+$16 = 0x816afbc "/home/yohgaki/php/DEV/segfault.php"
+(gdb)
+ </code></pre>
+</ul>
+
+<p>In this session, frame 3 is the last <b><code>execute()</code></b> call. The
+<b><code>frame 3</code></b> command moves the current working stack to the
+proper frame.<br>
+<b><code>print (char
*)(executor_globals.function_state_ptr->function)->common.function_name</code></b><br>
+prints the function name. In the sample gdb session, the
+<code>pg_result_error()</code> call is causing the segfault. You can print any
+internal data that you like, if you know the internal data structure. Please do
+not ask how to use gdb or about the internal data structure. Refer to gdb
manual
+for gdb usage and to the PHP source for the internal data structure.</p>
+
+<p>You may not see <b><code>execute</code></b> if the segfault happens without
+calling any functions.</p>
+
+<?php $this->end('content') ?>
diff --git a/templates/pages/bugs_generating_backtrace_win32.php
b/templates/pages/bugs_generating_backtrace_win32.php
new file mode 100644
index 0000000..985be24
--- /dev/null
+++ b/templates/pages/bugs_generating_backtrace_win32.php
@@ -0,0 +1,105 @@
+<?php $this->extends('layout.php', ['title' => 'Generating a backtrace on
Windows']) ?>
+
+<?php $this->start('content') ?>
+
+<p>
+<a href="/bugs-generating-backtrace.php">Unix</a> | <strong>Windows</strong>
+</p>
+
+<h1>Generating a backtrace, <u>with</u> a compiler, on Windows</h1>
+
+<p>You'll need to install MS Visual Studio 2008, 2012 or later. You'll also
need to</p>
+<ul>
+ <li>either download the debug-pack for your PHP version from <a
href="https://windows.php.net/download/";>windows.php.net/download</a></li>
+ <li>or compile your own PHP with <code>--enable-dbg-pack</code> or
<code>--enable-debug</code></li>
+</ul>
+
+<p>If you downloaded the debug-pack from the snaps site, extract it into your
+PHP directory and be sure to put the PDB files that belong to the extensions
+into your extension directory.</p>
+
+<p>If you compile PHP by your own, you can also use a newer version of
MSVC.</p>
+
+<p>When PHP crashes, click <em>Cancel</em> to debug the process. Now MSVC
starts
+up in <em>Debug View</em>. If you don't already see the call stack, go into the
+<em>View</em> menu and choose <em>Debug Windows</em> → <em>Call
Stack</em>.</p>
+
+<p>You'll now see something similar to the following lines, this is the
backtrace:</p>
+<pre><code>
+_efree(void * 0x00000000) line 286 + 3 bytes
+zif_http_test(int 0, _zval_struct * 0x007bc3b0, _zval_struct * * 0x00000000,
_zval_struct * 0x00000000, int 0, void * * * 0x00792cd0) line 1685 + 8 bytes
+zend_do_fcall_common_helper_SPEC(_zend_execute_data * 0x0012fd6c, void * * *
0x00792cd0) line 188 + 95 bytes
+ZEND_DO_FCALL_SPEC_CONST_HANDLER(_zend_execute_data * 0x0012fd6c, void * * *
0x00792cd0) line 1578 + 13 bytes
+execute(_zend_op_array * 0x007bc880, void * * * 0x00792cd0) line 88 + 13 bytes
+zend_eval_string(char * 0x00793bce, _zval_struct * 0x00000000, char *
0x00404588 tring', void * * * 0x00792cd0) line 1056 + 14 bytes
+zend_eval_string_ex(char * 0x00793bce, _zval_struct * 0x00000000, char *
0x00404588 tring', int 1, void * * * 0x00792cd0) line 1090 + 21 bytes
+main(int 3, char * * 0x00793ba8) line 1078 + 23 bytes
+PHP! mainCRTStartup + 227 bytes
+KERNEL32! 77e81af6()
+</code></pre>
+
+<!--
+ Everything below is stolen from Pierre Joye
+
https://blog.thepimp.net/index.php/post/2007/06/10/debug-pack-or-how-to-generate-backtrack-on-windows-without-compiling
+-->
+<h1>Generating backtrace, <u>without</u> compiler, on Windows</h1>
+
+<p>You'll need:</p>
+
+<ul>
+<li>A PHP <a href="https://windows.php.net/downloads/snaps/";>snapshot</a> or
<a href="https://windows.php.net/download/";>stable</a> release</li>
+<li>PHP Debug pack (<a
href="https://windows.php.net/downloads/snaps/";>snapshot</a> or <a
href="https://windows.php.net/download/";>stable</a>)</li>
+<li>Microsoft <a
href="https://www.microsoft.com/en-us/download/details.aspx?id=49924";>Debug
Diagnostic Tools</a></li>
+<li>Evil script to crash PHP</li>
+</ul>
+
+<p>For the sake of this example, we will simply use PHP in the shell. The same
+method can be used for IIS or any other process or services.</p>
+
+
+<p>Once you have installed the Debug diagnostic tools and uncompressed PHP and
+its debug pack (they can be kept in two separate folders), the first step is to
+configure the diagnostic tools. Select the tools menu and click on "Options and
+settings". The first tab contains the path to the symbols files, add the "debug
+folder" to the existing list using the "browse" button:</p>
+
+<p><img src="/images/backtrace-images-win32/dbg_options.png" alt="Options"></p>
+
+<p>Now we are ready to generate our backtrace.</p>
+
+<p>We will use the wizard, click the "Add a rule" button and choose "Crash" as
+the rule type:</p>
+<p><img src="/images/backtrace-images-win32/dbg_wizard_1.png" alt="Wizard
#1"></p>
+
+<p>In the next window, select "a specific process":</p>
+
+<p><img src="/images/backtrace-images-win32/dbg_wizard_2.png" alt="Wizard
#2"></p>
+
+<p>Add a "sleep(10);" for the first run (from the cmd: "php.exe crashme.php"),
+it will let you enough time to click "next" and select the php process. If you
+are debugging the Apache module, start Apache with -X option and choose
+httpd.exe instead of php.exe from the process list. Then proceed further:</p>
+
+<p><img src="/images/backtrace-images-win32/dbg_select_php.png" alt="Select
the php process"></p>
+
+<p>Click again next and let it crash. If everything went well, you should see
+your new rule as shown in the image below:</p>
+
+<p><img src="/images/backtrace-images-win32/rules.jpg" alt="rules list"></p>
+
+<p>It also detected that "php.exe" was used. A rule has been created for all
+instance of "php.exe". It will save you the sleep and process selection.</p>
+
+<p>Now you can click the "Analyze data" button:</p>
+
+<p><img src="/images/backtrace-images-win32/analyze.jpg" alt="Analyze"></p>
+
+<p>Et voila, the complete report will show up in your internet explorer
+(compressed html):</p>
+
+<p><img src="/images/backtrace-images-win32/backtrace.jpg" alt="Debug report
backtrace screenshot"></a></p>
+
+<p>What we need is the backtrace itself which can be found under "Thread X -
+System ID XXX".</p>
+
+<?php $this->end('content') ?>
diff --git a/www/bugs-generating-backtrace-win32.php
b/www/bugs-generating-backtrace-win32.php
index a12c26a..cc09a36 100644
--- a/www/bugs-generating-backtrace-win32.php
+++ b/www/bugs-generating-backtrace-win32.php
@@ -1,99 +1,14 @@
<?php
-session_start();
+/**
+ * Page with a quick info how to generate backtrace with compiler on Windows.
+ */
-require_once '../include/prepend.php';
+// Application bootstrap
+require_once __DIR__.'/../include/prepend.php';
-// Authenticate
-bugs_authenticate($user, $pw, $logged_in, $user_flags);
+// Authentication
+require_once __DIR__.'/../include/auth.php';
-response_header('Generating a backtrace on Windows');
-
-backtrace_inline_menu('Windows');
-?>
-
-<h1>Generating a backtrace, <u>with</u> a compiler, on Windows</h1>
-
-<p>You'll need to install MS Visual Studio 2008, 2012 or later. You'll also
need to</p>
-<ul>
- <li>either download the debug-pack for your PHP version from <a
href="https://windows.php.net/download/";>windows.php.net/download</a></li>
- <li>or compile your own PHP with <code>--enable-dbg-pack</code> or
<code>--enable-debug</code></li>
-</ul>
-
-<p>If you downloaded the debug-pack from the snaps site, extract it into
-your PHP directory and be sure to put the PDB files that belong to the
-extensions into your extension directory.</p>
-
-<p>If you compile PHP by your own, you can also use a newer version of
MSVC.</p>
-
-<p>When PHP crashes, click <em>Cancel</em> to debug the process. Now MSVC
starts
-up in <em>Debug View</em>. If you don't already see the call stack, go into
the
-<em>View</em> menu and choose <em>Debug Windows</em> → <em>Call
Stack</em>.</p>
-
-<p>You'll now see something similar to the following lines, this is the
backtrace:</p>
-<pre><code>
-_efree(void * 0x00000000) line 286 + 3 bytes
-zif_http_test(int 0, _zval_struct * 0x007bc3b0, _zval_struct * * 0x00000000,
_zval_struct * 0x00000000, int 0, void * * * 0x00792cd0) line 1685 + 8 bytes
-zend_do_fcall_common_helper_SPEC(_zend_execute_data * 0x0012fd6c, void * * *
0x00792cd0) line 188 + 95 bytes
-ZEND_DO_FCALL_SPEC_CONST_HANDLER(_zend_execute_data * 0x0012fd6c, void * * *
0x00792cd0) line 1578 + 13 bytes
-execute(_zend_op_array * 0x007bc880, void * * * 0x00792cd0) line 88 + 13 bytes
-zend_eval_string(char * 0x00793bce, _zval_struct * 0x00000000, char *
0x00404588 tring', void * * * 0x00792cd0) line 1056 + 14 bytes
-zend_eval_string_ex(char * 0x00793bce, _zval_struct * 0x00000000, char *
0x00404588 tring', int 1, void * * * 0x00792cd0) line 1090 + 21 bytes
-main(int 3, char * * 0x00793ba8) line 1078 + 23 bytes
-PHP! mainCRTStartup + 227 bytes
-KERNEL32! 77e81af6()
-</code></pre>
-
-<!--
- Everything below is stolen from Pierre Joye
-
https://blog.thepimp.net/index.php/post/2007/06/10/debug-pack-or-how-to-generate-backtrack-on-windows-without-compiling
--->
-<h1>Generating backtrace, <u>without</u> compiler, on Windows</h1>
-<p>You'll need:</p>
-<ul>
-<li>A PHP <a href="https://windows.php.net/downloads/snaps/";>snapshot</a> or
<a href="https://windows.php.net/download/";>stable</a> release</li>
-<li>PHP Debug pack (<a
href="https://windows.php.net/downloads/snaps/";>snapshot</a> or <a
href="https://windows.php.net/download/";>stable</a>)</li>
-<li>Microsoft <a
href="https://www.microsoft.com/en-us/download/details.aspx?id=49924";>Debug
Diagnostic Tools</a></li>
-<li>Evil script to crash PHP</li>
-</ul>
-<p>For the sake of this example, we will simply use PHP in the shell.
-The same method can be used for IIS or any other process or services.</p>
-
-
-<p>Once you have installed the Debug diagnostic tools and uncompressed
-PHP and its debug pack (they can be kept in two separate folders), the
-first step is to configure the diagnostic tools. Select the
-tools menu and click on "Options and settings". The first tab contains
-the path to the symbols files, add the "debug folder" to the existing
-list using the "browse" button:</p>
-<p><img src="/images/backtrace-images-win32/dbg_options.png" alt="Options"></p>
-
-<p>Now we are ready to generate our backtrace.</p>
-<p>We will use the wizard, click the "Add a rule" button and choose "Crash" as
the rule type:</p>
-<p><img src="/images/backtrace-images-win32/dbg_wizard_1.png" alt="Wizard
#1"></p>
-
-<p>In the next window, select "a specific process":</p>
-<p><img src="/images/backtrace-images-win32/dbg_wizard_2.png" alt="Wizard
#2"></p>
-
-<p>Add a "sleep(10);" for the first run (from the cmd: "php.exe
-crashme.php"), it will let you enough time to click "next" and select
-the php process. I you are debugging the Apache module, start Apache with -X
option and choose
-httpd.exe instead of php.exe from the process list.
-Then proceed further:</p>
-<p><img src="/images/backtrace-images-win32/dbg_select_php.png" alt="Select
the php process"></p>
-
-<p>Click again next and let it crash. If everything went well, you should see
your new rule as shown in the image below:</p>
-<p><img src="/images/backtrace-images-win32/rules.jpg" alt="rules list"></p>
-
-<p>It also detected that "php.exe" was used. A rule has been created
-for all instance of "php.exe". It will save you the sleep and process
-selection.</p>
-<p>Now you can click the "Analyze data" button:</p>
-<p><img src="/images/backtrace-images-win32/analyze.jpg" alt="Analyze"></p>
-
-<p>Et voila, the complete report will show up in your internet explorer
(compressed html):</p>
-<p><img src="/images/backtrace-images-win32/backtrace.jpg" alt="Debug report
backtrace screenshot"></a></p>
-
-<p>What we need is the backtrace itself which can be found under "Thread X -
System ID XXX".</p>
-
-<?php response_footer();
+// Output template with given template variables.
+echo $template->render('pages/bugs_generating_backtrace_win32.php');
diff --git a/www/bugs-generating-backtrace.php
b/www/bugs-generating-backtrace.php
index 5e6fafc..4729ec6 100644
--- a/www/bugs-generating-backtrace.php
+++ b/www/bugs-generating-backtrace.php
@@ -1,192 +1,14 @@
<?php
-session_start();
+/**
+ * Page with a quick info how to generate gdb backtrace on Unix.
+ */
-require_once '../include/prepend.php';
+// Application bootstrap
+require_once __DIR__.'/../include/prepend.php';
-// Authenticate
-bugs_authenticate($user, $pw, $logged_in, $user_flags);
+// Authentication
+require_once __DIR__.'/../include/auth.php';
-response_header('Generating a gdb backtrace');
-
-backtrace_inline_menu('Unix');
-
-?>
-
-<h1>Generating a gdb backtrace</h1>
-
-<h3>Noticing PHP crashes</h3>
-
-There's no absolute way to know that PHP is crashing, but there may
-be signs. Typically, if you access a page that is always supposed
-to generate output (has a leading HTML block, for example), and
-suddenly get "Document contains no data" from your browser, it may
-mean that PHP crashes somewhere along the execution of the script.
-Another way to tell that PHP is crashing is by looking at the Apache
-error logs, and looking for SEGV (Apache 1.2) or Segmentation
-Fault (Apache 1.3).
-
-<h3>Important!</h3>
-To get a backtrace with correct information you must have
-PHP configured with <code>--enable-debug</code>!
-
-<h3>If you don't have a core file yet:</h3>
-
-<ul>
- <li>
- Remove any limits you may have on core dump size from your shell:
- <ul>
- <li>tcsh: unlimit coredumpsize</li>
- <li>bash/sh: ulimit -c unlimited</li>
- </ul>
- </li>
- <li>
- Ensure that the directory in which you're running PHP, or the
- PHP-enabled httpd, has write permissions for the user who's running
PHP.
- </li>
- <li>
- Cause PHP to crash:
- <ul>
- <li>PHP CGI: Simply run php with the script that crashes it</li>
- <li>PHP Apache Module: Run httpd -X, and access the script that
crashes PHP</li>
- </ul>
- </li>
-</ul>
-
-<h3>Generic way to get a core on Linux</h3>
-
-<ul>
- <li>
- Set up the core pattern (run this command as <i>root</i>):
- <ul>
- <li>echo "<cores dir>/core-%e.%p" >
/proc/sys/kernel/core_pattern</li>
- <li>make sure the directory is writable by PHP</li>
- </ul>
- </li>
- <li>
- Set the ulimit (see above how to do it).
- </li>
- <li>
- Restart/rerun PHP.
- </li>
-</ul>
-<p>After that any process crashing in your system, including PHP, will leave
-its core file in the directory you've specified in <i>core_pattern</i>.</p>
-
-<h3>Once you have the core file:</h3>
-
-<ul>
- <li>
- Run gdb with the path to the PHP or PHP-enabled httpd binary, and
- path to the core file. Some examples:
- <ul>
- <li><code>gdb /usr/local/apache/sbin/httpd
/usr/local/apache/sbin/core</code></li>
- <li><code>gdb /home/user/dev/php-snaps/sapi/cli/php
/home/user/dev/testing/core</code></li>
- </ul>
- </li>
- <li>
- At the gdb prompt, run:
- <ul>
- <li><code>(gdb) bt</code></li>
- </ul>
- </li>
-</ul>
-
-<h3>If you can't get a core file:</h3>
-<ul>
- <li>
- Run httpd -X under gdb with something like:
- <ul>
- <li><code>gdb /usr/local/apache/sbin/httpd</code></li>
- <li>(gdb) run -X</li>
- </ul>
- </li>
- <li>
- Then use your web browser and access your server to force the crash.
- You should see a gdb prompt appear and some message indicating that
- there was a crash. At this gdb prompt, type:
- <ul>
- <li><code>(gdb) bt</code></li>
- </ul>
- <ul>
- <li>
- or, running from the commandline
- <ul>
- <li>
- gdb /home/user/dev/php-snaps/sapi/cli/php
- <ul>
- <li><code>(gdb) run /path/to/script.php</code></li>
- <li><code>(gdb) bt</code></li>
- </ul>
- </li>
- </ul>
- </li>
- </ul>
- </li>
-</ul>
-
-<p>This should generate a backtrace, that you should submit in
-the bug report, along with any other details you can give us
-about your setup, and offending script.</p>
-
-<h3>Locating which function call caused a segfault:</h3>
-
-<p>You can locate the function call that caused a segfault, easily, with gdb.
-First, you need a core file or to generate a segfault under gdb as described
-above.</p>
-
-<p>In PHP, each function is executed by an internal function called
-<b><code>execute()</code></b> and has its own stack. Each line
-generated by the <b><code>bt</code></b> command represents a function call
-stack. Typically, you will see several <b><code>execute()</code></b> lines
-when you issue <b><code>bt</code></b>. You are interested in the last
-<b><code>execute()</code></b> stack (i.e. smallest frame
-number). You can move the current working stack with the
-<b><code>up</code></b>, <code>down</code> or
-<b><code>frame</code></b> commands. Below is an example gdb session that can
-be used as a guideline on how to handle your segfault.</p>
-
-<ul>
- <li>Sample gdb session</li>
- <pre><code>
-(gdb) bt
-#0 0x080ca21b in _efree (ptr=0xbfffdb9b) at zend_alloc.c:240
-#1 0x080d691a in _zval_dtor (zvalue=0x8186b94) at zend_variables.c:44
-#2 0x080cfab3 in _zval_ptr_dtor (zval_ptr=0xbfffdbfc) at
zend_execute_API.c:274
-#3 0x080f1cc4 in execute (op_array=0x816c670) at ./zend_execute.c:1605
-#4 0x080f1e06 in execute (op_array=0x816c530) at ./zend_execute.c:1638
-#5 0x080f1e06 in execute (op_array=0x816c278) at ./zend_execute.c:1638
-#6 0x080f1e06 in execute (op_array=0x8166eec) at ./zend_execute.c:1638
-#7 0x080d7b93 in zend_execute_scripts (type=8, retval=0x0, file_count=3) at
zend.c:810
-#8 0x0805ea75 in php_execute_script (primary_file=0xbffff650) at main.c:1310
-#9 0x0805cdb3 in main (argc=2, argv=0xbffff6fc) at cgi_main.c:753
-#10 0x400c91be in __libc_start_main (main=0x805c580 <main>, argc=2,
ubp_av=0xbffff6fc,
- init=0x805b080 <_init>, fini=0x80f67b4 <_fini>,
rtld_fini=0x4000ddd0 <_dl_fini>,
- stack_end=0xbffff6ec) at ../sysdeps/generic/libc-start.c:129
-(gdb) frame 3
-#3 0x080f1cc4 in execute (op_array=0x816c670) at ./zend_execute.c:1605
-(gdb) print (char
*)(executor_globals.function_state_ptr->function)->common.function_name
-$14 = 0x80fa6fa "pg_result_error"
-(gdb) print (char *)executor_globals.active_op_array->function_name
-$15 = 0x816cfc4 "result_error"
-(gdb) print (char *)executor_globals.active_op_array->filename
-$16 = 0x816afbc "/home/yohgaki/php/DEV/segfault.php"
-(gdb)
- </code></pre>
-</ul>
-
-<p>In this session, frame 3 is the last <b><code>execute()</code></b>
-call. The <b><code>frame 3</code></b> command moves the current working stack
-to the proper frame.<br>
-<b><code>print (char
*)(executor_globals.function_state_ptr->function)->common.function_name</code></b><br>
-prints the function name. In the sample gdb session, the
-<code>pg_result_error()</code> call
-is causing the segfault. You can print any internal data that you like,
-if you know the internal data structure. Please do not ask how to use gdb
-or about the internal data structure. Refer to gdb manual for gdb usage
-and to the PHP source for the internal data structure.</p>
-
-<p>You may not see <b><code>execute</code></b> if the segfault happens
-without calling any functions.</p>
-
-<?php response_footer();
+// Output template with given template variables.
+echo $template->render('pages/bugs_generating_backtrace.php');
--
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