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>
Device URI was not filled for non-Avahi printers by my previous commit.
I've added it back. It was a mistake during rebasing of the patch
to current master.
Create printer name from name of the advertised service
for standalone IPP printers as opposed to CUPS printers
advertised via Avahi which get name from their
resource path.
This is similar to what cups-filters does.
Pass GtkPrinter class to request for printer info
so that it does not need to be searched for
(such search could fail for standalone IPP printers).
https://gitlab.gnome.org/GNOME/gtk/issues/1509
Set reasonable default values for printers discovered
by Avahi which do not have 'printer-type' attribute.
This is the case for network printers which were not
published by CUPS.
Related to the issue #1509.
The http* family of functions was deprecated after CUPS 1.7. We can
conditionally use it when built against a newer version of CUPS. The
additional parameters are taken directly from the fallback values
inside CUPS itself.
Additional code improvements and fixes:
- Use g_regex_match_simple() instead of sscanf()
- Added spaces between function names and left parantheses
- Set always correct custom page size
- Added page_setup field to CupsOptionsData data structure
- Replaced tab indentions by spaces
- Moved #define out of add_cups_options() function, removed line breaks from regular expressions
to retreive paper size specific hard margins and use this
to set the hard margins in the print context.
(modified by Marek Kasik <mkasik@redhat.com>)
https://bugzilla.gnome.org/show_bug.cgi?id=686109
When using strncpy() with a buffer we need to account for the
terminating NUL character. GCC 8 started warning when using PPD_MAX_NAME
as the buffer length for strncpy() because the buffer we're copying into
has the same length — which means that the terminating NUL may be
skipped if the source string has a length of PPD_MAX_NAME.
The appropriate way to handle the case where we're copying a source with
a length bigger than of PPD_MAX_NAME is, as reported in the strncpy()
documentation, to copy `PPD_MAX_NAME - 1` bytes, and explicitly NUL
terminate the destination buffer. This has the additional benefit of
avoiding the compiler warning.
