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4075c52b69
Before this fix, a thread instrumented for the performance schema, that would perform file io operations, could crash inside the LF_HASH implementation, in cases when my_thread_init is not called. The crash itself has not been reported in 5.5 but similar crashes have been found in 5.6-based development branches, using LF_HASH for more instrumentation. The possibility of a crash in 5.5 is confirmed by code analysis. The problem is that, when my_thread_init() is not called, which can happen for threads in storage engines or thirs party code, my_thread_var is NULL. Using my_thread_var->stacks_ends_here in mysys/lf_alloc-pin.c is unsafe. Given that my_thread_var is used: - only for stacks_ends_here - only on platform with HAVE_ALLOCA - only when there is enough room on the stack and given that the LF_HASH implementation has a fallback algorythm implemented already when using alloca is not possible, using my_thread_var->stacks_ends_here is in fact not a strict requirement, and can be relaxed. The fix is to: - test explicitly if my_thread_var is NULL, to account for cases when my_thread_init() is not used by the calling thread. - not use alloca in this case, and rely on the fall back code already in place. so that the LF_HASH can be supported even without my_thread_init(). The implementation of mysys/lf_alloc-pin.c has been fixed to support this new usage. The units tests in unittest/mysys/lf-t.c have been adjusted accordingly. |
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| .. | ||
| examples | ||
| mysys | ||
| mytap | ||
| strings | ||
| README.txt | ||
| unit.pl | ||
Unit tests directory structure
------------------------------
This is the current structure of the unit tests. More directories
will be added over time.
mytap Source for the MyTAP library
mysys Tests for mysys components
bitmap-t.c Unit test for MY_BITMAP
base64-t.c Unit test for base64 encoding functions
examples Example unit tests.
core-t.c Example of raising a signal in the middle of the test
THIS TEST WILL STOP ALL FURTHER TESTING!
simple-t.c Example of a standard TAP unit test
skip-t.c Example where some test points are skipped
skip_all-t.c Example of a test where the entire test is skipped
todo-t.c Example where test contain test points that are TODO
no_plan-t.c Example of a test with no plan (avoid this)
Executing unit tests
--------------------
To make and execute all unit tests in the directory:
make test
Observe that the tests in the examples/ directory are just various
examples of tests and are not expected to pass.
Adding unit tests
-----------------
Add a file with a name of the format "foo-t.c" to the appropriate
directory and add the following to the Makefile.am in that directory
(where ... denotes stuff already there):
noinst_PROGRAMS = ... foo-t
Note, it's important to have "-t" at the end of the filename, otherwise the
test won't be executed by 'make test' !
Documentation
-------------
The generated documentation is temporarily placed at:
http://www.kindahl.net/mytap/doc/
I will move it to a better place once I figure out where and how.