Edit report at https://bugs.php.net/bug.php?id=61584&edit=1
ID: 61584
User updated by: osama dot sorour at eformations dot net
Reported by: osama dot sorour at eformations dot net
Summary: when using readline_info to set line_buffer, it
causes memory corruption
-Status: Feedback
+Status: Open
Type: Bug
Package: Readline related
Operating System: Linux
PHP Version: 5.4.0
Block user comment: N
Private report: N
New Comment:
It is almost impossible to make it happen on purpose. It happened in my code,
which was thousands of lines long with about 30 classes. In addition, when it
used to happen, it used to happen randomly at different locations.
Please note that regardless of reproduction, the method used in the current
code
to set the readline buffer is wrong. Please refer to the patch and readline
documentation:
Variable: char * rl_line_buffer
This is the line gathered so far. You are welcome to modify the contents of the
line, but see 2.4.5 Allowing Undoing. The function rl_extend_line_buffer is
available to increase the memory allocated to rl_line_buffer.
which clearly indicates that you are only allowed to change it, not replace the
buffer pointer as it is done in the current code.
>From the readline documentation, here is the correct way of completely
>replacing
the buffer:
Function: void rl_replace_line (const char *text, int clear_undo)
Replace the contents of rl_line_buffer with text. The point and mark are
preserved, if possible. If clear_undo is non-zero, the undo list associated
with
the current line is cleared.
Previous Comments:
------------------------------------------------------------------------
[2012-05-20 23:32:21] [email protected]
Thank you for this bug report. To properly diagnose the problem, we
need a short but complete example script to be able to reproduce
this bug ourselves.
A proper reproducing script starts with <?php and ends with ?>,
is max. 10-20 lines long and does not require any external
resources such as databases, etc. If the script requires a
database to demonstrate the issue, please make sure it creates
all necessary tables, stored procedures etc.
Please avoid embedding huge scripts into the report.
------------------------------------------------------------------------
[2012-03-31 19:08:23] osama dot sorour at eformations dot net
Description:
------------
Using the function readline_info to set the property "line_buffer" performs a
direct setting of readline rl_line_buffer. It works for short lived scripts but
for longer ones, they start to crash randomly with sig violations.
The proper way for libreadline is to use rl_replace_line to set the line buffer.
In addition, readline_info does not allow you to set "point" and "end"
properties
that are needed when changing line_buffer.
I've included a patch that fixes the setting of "line_buffer" and adds the
ability to set both "point" and "end" properties.
Test script:
---------------
None. Random crashes.
Expected result:
----------------
None.
Actual result:
--------------
None.
------------------------------------------------------------------------
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Edit this bug report at https://bugs.php.net/bug.php?id=61584&edit=1
