XML feature description support.

	* NEWS: Mention target descriptions, "set tdesc filename",
	"unset tdesc filename", "show tdesc filename", and
	qXfer:features:read.
	* arch-utils.c (choose_architecture_for_target): New function.
	(gdbarch_info_fill): Call it.
	* target-descriptions.c (struct property): Make members non-const.
	(struct target_desc): Add arch member.
	(target_description_filename): New variable.
	(target_find_description): Try via XML first.
	(tdesc_architecture): New.
	(free_target_description, make_cleanup_free_target_description): New.
	(set_tdesc_property): Call xstrdup.
	(set_tdesc_architecture, tdesc_set_cmdlist, tdesc_show_cmdlist)
	(tdesc_unset_cmdlist, unset_tdesc_cmd, unset_tdesc_filename_cmd)
	(set_tdesc_cmd, show_tdesc_cmd, set_tdesc_filename_cmd)
	(show_tdesc_filename_cmd, _initialize_target_descriptions): New.
	* target-descriptions.h (tdesc_architecture)
	(make_cleanup_free_target_description, set_tdesc_architecture): New
	prototypes.
	* Makefile.in (SFILES): Add xml-tdesc.c.
	(COMMON_OBS): Add xml-tdesc.o.
	(target-descriptions.o): Update.
	(xml-tdesc.o): New rule.
	* xml-tdesc.c, xml-tdesc.h: New files.
	* remote.c (PACKET_qXfer_features): New enum.
	(remote_protocol_features): Add qXfer:features:read.
	(remote_xfer_partial): Handle TARGET_OBJECT_AVAILABLE_FEATURES.
	(_initialize_remote): Register qXfer:features:read.
	* target.h (enum target_object): Add TARGET_OBJECT_AVAILABLE_FEATURES.
	* features/gdb-target.dtd: New file.

	* linux-i386-low.c (the_low_target): Set arch_string.
	* linux-x86-64-low.c (the_low_target): Likewise.
	* linux-low.c (linux_arch_string): New.
	(linux_target_ops): Add it.
	* linux-low.h (struct linux_target_ops): Add arch_string.
	* server.c (write_qxfer_response): Use const void * for DATA.
	(get_features_xml): New.
	(handle_query): Handle qXfer:features:read.  Report it for qSupported.
	* target.h (struct target_ops): Add arch_string method.

	* gdb.texinfo (Target Descriptions): New section.
	(General Query Packets): Add QPassSignals anchor.  Mention
	qXfer:features:read under qSupported.  Expand mentions of
	qXfer:memory-map:read and QPassSignals.  Document
	qXfer:features:read.

1 files changed, 11 insertions, 0 deletions

diff --git a/gdb/remote.c b/gdb/remote.c
index c229bff..48be844 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -893,6 +893,7 @@ enum {
   PACKET_Z3,
   PACKET_Z4,
   PACKET_qXfer_auxv,
+  PACKET_qXfer_features,
   PACKET_qXfer_memory_map,
   PACKET_qGetTLSAddr,
   PACKET_qSupported,
@@ -2294,6 +2295,8 @@ static struct protocol_feature remote_protocol_features[] = {
   { "PacketSize", PACKET_DISABLE, remote_packet_size, -1 },
   { "qXfer:auxv:read", PACKET_DISABLE, remote_supported_packet,
     PACKET_qXfer_auxv },
+  { "qXfer:features:read", PACKET_DISABLE, remote_supported_packet,
+    PACKET_qXfer_features },
   { "qXfer:memory-map:read", PACKET_DISABLE, remote_supported_packet,
     PACKET_qXfer_memory_map },
   { "QPassSignals", PACKET_DISABLE, remote_supported_packet,
@@ -5716,6 +5719,11 @@ remote_xfer_partial (struct target_ops *ops, enum target_object object,
       return remote_read_qxfer (ops, "auxv", annex, readbuf, offset, len,
 				&remote_protocol_packets[PACKET_qXfer_auxv]);
 
+    case TARGET_OBJECT_AVAILABLE_FEATURES:
+      return remote_read_qxfer
+	(ops, "features", annex, readbuf, offset, len,
+	 &remote_protocol_packets[PACKET_qXfer_features]);
+
     case TARGET_OBJECT_MEMORY_MAP:
       gdb_assert (annex == NULL);
       return remote_read_qxfer (ops, "memory-map", annex, readbuf, offset, len,
@@ -6589,6 +6597,9 @@ Show the maximum size of the address (in bits) in a memory packet."), NULL,
   add_packet_config_cmd (&remote_protocol_packets[PACKET_qXfer_auxv],
 			 "qXfer:auxv:read", "read-aux-vector", 0);
 
+  add_packet_config_cmd (&remote_protocol_packets[PACKET_qXfer_features],
+			 "qXfer:features:read", "target-features", 0);
+
   add_packet_config_cmd (&remote_protocol_packets[PACKET_qXfer_memory_map],
 			 "qXfer:memory-map:read", "memory-map", 0);