printer_name_compressed_strv is NULL-terminated array
of gchar*, which means N+1 memory should be allocated.
Otherwise, if the printer name has no empty components
(which is usually the case), printer_name_compressed_strv[N],
which should contain the NULL sentinel, will actually lie
just outside of allocated memory, which is UB.
In my case, it led to crashes inside g_strjoinv
when Print... dialog is opened in evince.
#0 0x00007fad2ce1bad7 in __strlen_avx2 () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:96
#1 0x00007fad2d04d88d in g_strjoinv (separator=separator@entry=0x7fad0c9bc508 "-", str_array=str_array@entry=0x556b017f0200) at ../glib-2.60.7/glib/gstrfuncs.c:2585
#2 0x00007fad0c9b8a89 in avahi_service_resolver_cb (source_object=<optimized out>, res=<optimized out>, user_data=0x7fad08020ee0) at /var/tmp/portage/x11-libs/gtk+-3.24.13/work/gtk+-3.24.13/modules/printbackends/cups/gtkprintbackendcups.c:3223
#3 0x00007fad2d1f8ed3 in g_task_return_now (task=0x556b017a8b00 [GTask]) at ../glib-2.60.7/gio/gtask.c:1209
#4 0x00007fad2d1f987d in g_task_return (task=0x556b017a8b00 [GTask], type=<optimized out>) at ../glib-2.60.7/gio/gtask.c:1278
#5 0x00007fad2d1f9dec in g_task_return (type=G_TASK_RETURN_SUCCESS, task=<optimized out>) at ../glib-2.60.7/gio/gtask.c:1678
#6 0x00007fad2d1f9dec in g_task_return_pointer (task=<optimized out>, result=<optimized out>, result_destroy=<optimized out>) at ../glib-2.60.7/gio/gtask.c:1683
#7 0x00007fad2d24b6af in g_dbus_connection_call_done (source=<optimized out>, result=0x556b017a8bc0, user_data=0x556b017a8b00) at ../glib-2.60.7/gio/gdbusconnection.c:5747
#8 0x00007fad2d1f8ed3 in g_task_return_now (task=0x556b017a8bc0 [GTask]) at ../glib-2.60.7/gio/gtask.c:1209
#9 0x00007fad2d1f8f09 in complete_in_idle_cb (task=0x556b017a8bc0) at ../glib-2.60.7/gio/gtask.c:1223
#10 0x00007fad2d02d2c0 in g_main_dispatch (context=0x556b00eee090) at ../glib-2.60.7/glib/gmain.c:3189
#11 0x00007fad2d02d2c0 in g_main_context_dispatch (context=context@entry=0x556b00eee090) at ../glib-2.60.7/glib/gmain.c:3854
#12 0x00007fad2d02d658 in g_main_context_iterate (context=context@entry=0x556b00eee090, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib-2.60.7/glib/gmain.c:3927
#13 0x00007fad2d02d6df in g_main_context_iteration (context=context@entry=0x556b00eee090, may_block=may_block@entry=1) at ../glib-2.60.7/glib/gmain.c:3988
#14 0x00007fad2d22248d in g_application_run (application=0x556b0116f130 [EvApplication], argc=<optimized out>, argv=<optimized out>) at ../glib-2.60.7/gio/gapplication.c:2519
#15 0x0000556b002e55a1 in ()
#16 0x00007fad2ccd6f1b in __libc_start_main (main=0x556b002e50d0, argc=2, argv=0x7ffe1057fa88, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffe1057fa78) at ../csu/libc-start.c:308
#17 0x0000556b002e567a in ()
(gdb) p printer_name_compressed_strv[0]
$4 = (gchar *) 0x556d4a4be430 "Brother"
(gdb) p printer_name_compressed_strv[1]
$5 = (gchar *) 0x7f9dbc011090 "MFC"
(gdb) p printer_name_compressed_strv[2]
$6 = (gchar *) 0x556d4a51ba50 "7860DW"
(gdb) p printer_name_compressed_strv[3]
$7 = (gchar *) 0x401 <error: Cannot access memory at address 0x401>
Instead of reporting the frame clock phases as defined,
report the duration of the signal emissions, which is more
useful for tracking down what is taking time.
Add marks for when we do commits, swap buffer or
receive frame events. These are the low-level start
and end points of the frame cycle, and it is useful
to see them in the profiler.
- many moons and some iterations later, these are the suggested
general typographic styles. Already being referenced in apps like
Banner Viewer (for now shipping custom definitions)
Fixes https://gitlab.gnome.org/GNOME/gtk/issues/1808
This is an attempt to see how we can use sysprof data
in our tests to extract useful performance numbers.
Use it as a wrapper around any GTK+ process:
./testperf ./gtk4-widget-factory
Currently, it repeatedly runs the given commandline,
extracts the first css validation time from the resulting
syscap file, and prints out the min/max/avg of the runs
at the end.
This relies on the environment variable GTK_DEBUG_AUTO_QUIT
to cause the process to exit soon after launch.
This call is not necessary, because gtk_css_node_set_parent() does the
right thing. (It probably hasn't been necessary for years, but I'm
not gonna try my luck on GTK3 at this stage.)
This code is usually called the first time
gtk_widget_get_style_context() is called on a widget and its style
context gets create. At that point however, the css nodes are in the
right place already, so no invalidation should happen.