This code was a persistent source of `-fsanitize=thread` errors
when I was trying to use it on OSTree.
The problem is that while I think this code is functionally correct,
we hold a mutex during the writes, but not the reads, and TSAN (IMO
correctly) flags that.
Reading this, I don't see a reason we need a mutex at all. At the
cost of some small code duplication between posix/win32, we can just
pass the data we need down into each implementation. This ends up
being notably cleaner I think than the awkward "lock/unlock to
serialize" dance.
(Minor review changes made by Philip Withnall <withnall@endlessm.com>.)
https://gitlab.gnome.org/GNOME/glib/issues/1224
This is a wrapper around g_private_set() which allocates the desired
amount of memory for the caller and calls g_private_set() on it.
This is intended to make it easier to suppress Valgrind warnings about
leaked memory, since g_private_set() is typically used to make one-time
per-thread allocations. We can now just add a blanket suppression rule
for any allocations inside g_private_set_alloc0().
Signed-off-by: Philip Withnall <withnall@endlessm.com>
All glib/*.{c,h} files have been processed, as well as gtester-report.
12 of those files are not licensed under LGPL:
gbsearcharray.h
gconstructor.h
glibintl.h
gmirroringtable.h
gscripttable.h
gtranslit-data.h
gunibreak.h
gunichartables.h
gunicomp.h
gunidecomp.h
valgrind.h
win_iconv.c
Some of them are generated files, some are licensed under a BSD-style
license and win_iconv.c is in the public domain.
Sub-directories inside glib/:
deprecated/: processed in a previous commit
glib-mirroring-tab/: already LGPLv2.1+
gnulib/: not modified, the code is copied from gnulib
libcharset/: a copy
pcre/: a copy
tests/: processed in a previous commit
https://bugzilla.gnome.org/show_bug.cgi?id=776504
Hide the definition of struct _GThread in gthreadprivate.h for now.
This is possibly an API break -- although the structure contents were
undocumented and it was not safe to access them in a meaningful way,
someone may have tried to do it anyway. We'll leave it here for a while
to see if it causes any problems.
Avoid merging its contents with GRealThread for now, just incase we need
to expose it again.
And remove the 'joinable' argument from g_thread_new() and
g_thread_new_full().
Change the wording in the docs. Clarify expectations for
(deprecated) g_thread_create().
GThread is freed using some very slightly confusing logic: if the thread
was created 'joinable', then the structure is freed after the join()
call succeeds (since we know the thread has exited). If the thread was
not created 'joinable' then the free is when the thread quits (since we
know 'join' will not be called later).
Move to a straight ref-counting system: 1 ref owned by the thread and 1
extra ref if the thread is joinable. Both thread quit and joining will
decrease the refcount by 1.
Keep track of if we created a thread for ourselves or if the GThread*
was allocated in response to g_thread_self() on a previously-unknown
thread.
Only call g_system_thread_free() in the first case.
Add g_system_thread_new() and g_system_thread_free(), implemented with
GSlice. Use those instead of g_new() and g_free().
Presently, the backends are both doing the same thing. This will change
soon.
...instead of having a 'next' pointer in the GThread struct.
Now GThread contains no fields used only by deprecated code (except for
the rather generic setup function field).
Thanks to the modifications in 3d4846d923,
GStaticPrivate is not so directly tied in with GThread anymore. It is
now a simple matter to cut it out completely by using a GPrivate to
store the GArray instead of storing it in the GThread.
This commit moves GStaticPrivate, g_thread_foreach and all
related functions and variables to gthread-deprecated.c. We
introduce some internal API to make this possible.
g_thread_foreach is not a very useful function, since there is
virtually nothing you can do with a GThread*, and implementing
it requires us to keep a list of threads around.
GStaticPrivate has been made redundant by adding comparable
capabilities to GPrivate.
https://bugzilla.gnome.org/show_bug.cgi?id=660635
Take out the half-private g_private_init() stuff and replace it with a
G_PRIVATE_INIT macro that allows specifying a GDestroyNotify.
Expose the GPrivate structure in a public header.
Add a g_private_replace() to (sort of) match the functionality of
g_static_mutex_set().
Improve the documentation.
Deprecate g_private_new().
-Include gthread.h in gregex.c as g_once_init_enter and g_once_init_leave
are used.
-Define prototype for g_thread_DllMain in gthreadprivate.h for Windows
Switch 'self' 'join' and 'create' from using the vtable to being called
via normal g_system_thread_* internal API (implemented in each of
gthread-{posix,win32}.c).
Again, we can put NULL in the vtable since these were never used from
gthread.h.
We remove the macros while at the same time switching all libglib users
from g_private_new() to g_private_init(). We deal with the strange
expectations of the libglib code that g_private_* should work before the
GPrivate has been initialised with a temporary shim.
- expose the structure types for GLib internal use only
- avoid infinite recursion hazards by ensuring that GPrivate never
calls back into any other part of GLib
- substantially rework the Windows implementation so that it never
holds locks, contains no arbitrary limits and doesn't waste
100*sizeof(void*) per thread
We have to keep the macro hacks for the time being since some code
inside libglib depends on it.
Remove the explicit thread initialisation functions for g_get_charset(),
g_get_filename_charsets() and g_get_language_names().
Add a lock around one remaining case of access to libcharset (the other
2 cases already have the lock).
Do a proper g_once_init_enter() style initialisation for the GLib
gettext functions.
https://bugzilla.gnome.org/show_bug.cgi?id=658683
