pidgin/pidgin

Fix incompatible type conversion errors
release-2.x.y
3 months ago, Elliott Sales de Andrade
488055ab5531
Fix incompatible type conversion errors

- A recent libxml2 changed its handler function to take a `const` pointer. It's
safe for us to have it, and them not, but the opposite way causes an implicit
cast warning.
- In relatively new GLib (many years now), `g_object_ref` casts its output to
match its input. This means we should not be casting to `G_OBJECT`, as that
is not the type it expects, and would translate to the output being `GObject`
instead of the original type.

This fixes the build in Fedora 40, which changes several incompatible pointer
conversion warnings into errors.

This patch is partially from the Fedora maintainer @yarda, with some corrections by me (to the `g_object_ref` portions.)

Testing Done:
Compiled in a Rawhide environment with this patch applied.

Bugs closed: PIDGIN-17850

Reviewed at https://reviews.imfreedom.org/r/2944/
/** @page cmd-signals Command Signals
@signals
@signal cmd-added
@signal cmd-removed
@endsignals
@see cmds.h
@signaldef cmd-added
@signalproto
void (*cmd_added)(const char *command, PurpleCmdPriority priority,
PurpleCmdFlag flag);
@endsignalproto
@signaldesc
Emitted when a new command is added.
@param command The new command.
@param priority The priority of the new command.
@param flag The command flags.
@endsignaldef
@signaldef cmd-removed
@signalproto
void (*cmd_removed)(const char *command);
@endsignalproto
@signaldesc
Emitted when a command is removed.
@param command The removed command.
@endsignaldef
*/