C++: dlsym casts in gdb/linux-thread-db.c and gdb/gdbserver/thread-db.c

Implicit void * -> function pointer conversion doesn't work in C++, so
in C++, we need to cast the result of dlsym.  This adds a few typedefs
and macros that make this easy.  GDBserver's version already had the
CHK macro, so I added it to GDB too.

Tested on x86_64 Fedora 20, native and gdbserver.

gdb/gdbserver/ChangeLog:
2015-08-04  Pedro Alves  <palves@redhat.com>

	* thread-db.c (struct thread_db): Use new typedefs.
	(try_thread_db_load_1): Define local TDB_DLSYM macro and use it in
	CHK calls.
	(disable_thread_event_reporting): Cast result of dlsym to
	destination function pointer type.
	(thread_db_mourn): Use td_ta_delete_ftype.

gdb/ChangeLog:
2015-08-04  Pedro Alves  <palves@redhat.com>

	* nat/gdb_thread_db.h (td_init_ftype, td_ta_new_ftype)
	(td_ta_map_lwp2thr_ftype, td_ta_thr_iter_ftype)
	(td_ta_event_addr_ftype, td_ta_set_event_ftype)
	(td_ta_clear_event_ftype, td_ta_event_getmsg_ftype)
	(td_thr_validate_ftype, td_thr_get_info_ftype)
	(td_thr_event_enable_ftype, td_thr_tls_get_addr_ftype)
	(td_thr_tlsbase_ftype, td_symbol_list_ftype, td_ta_delete_ftype):
	New typedefs.
	* linux-thread-db.c (struct thread_db_info): Use new typedefs.
	(try_thread_db_load_1): Define TDB_VERBOSE_DLSYM, TDB_DLSYM , CHK
	local macros and use them instead of verbose_dlsym and dlsym
	calls.

1 files changed, 38 insertions, 0 deletions

diff --git a/gdb/nat/gdb_thread_db.h b/gdb/nat/gdb_thread_db.h
index a1d9473..2938eaf 100644
--- a/gdb/nat/gdb_thread_db.h
+++ b/gdb/nat/gdb_thread_db.h
@@ -14,3 +14,41 @@
    libthread_db associated with whatever libpthread the app is using.  */
 #define LIBTHREAD_DB_SEARCH_PATH "$sdir:$pdir"
 #endif
+
+/* Types of the libthread_db functions.  */
+
+typedef td_err_e (td_init_ftype) (void);
+
+typedef td_err_e (td_ta_new_ftype) (struct ps_prochandle * ps,
+				    td_thragent_t **ta);
+typedef td_err_e (td_ta_map_lwp2thr_ftype) (const td_thragent_t *ta,
+					    lwpid_t lwpid, td_thrhandle_t *th);
+typedef td_err_e (td_ta_thr_iter_ftype) (const td_thragent_t *ta,
+					 td_thr_iter_f *callback, void *cbdata_p,
+					 td_thr_state_e state, int ti_pri,
+					 sigset_t *ti_sigmask_p,
+					 unsigned int ti_user_flags);
+typedef td_err_e (td_ta_event_addr_ftype) (const td_thragent_t *ta,
+					   td_event_e event, td_notify_t *ptr);
+typedef td_err_e (td_ta_set_event_ftype) (const td_thragent_t *ta,
+					  td_thr_events_t *event);
+typedef td_err_e (td_ta_clear_event_ftype) (const td_thragent_t *ta,
+					    td_thr_events_t *event);
+typedef td_err_e (td_ta_event_getmsg_ftype) (const td_thragent_t *ta,
+					     td_event_msg_t *msg);
+
+typedef td_err_e (td_thr_validate_ftype) (const td_thrhandle_t *th);
+typedef td_err_e (td_thr_get_info_ftype) (const td_thrhandle_t *th,
+					  td_thrinfo_t *infop);
+typedef td_err_e (td_thr_event_enable_ftype) (const td_thrhandle_t *th,
+					      int event);
+
+typedef td_err_e (td_thr_tls_get_addr_ftype) (const td_thrhandle_t *th,
+					      psaddr_t map_address,
+					      size_t offset, psaddr_t *address);
+typedef td_err_e (td_thr_tlsbase_ftype) (const td_thrhandle_t *th,
+					 unsigned long int modid,
+					 psaddr_t *base);
+
+typedef const char ** (td_symbol_list_ftype) (void);
+typedef td_err_e (td_ta_delete_ftype) (td_thragent_t *);