Add a new DDB(4) facility, output capture. Input and output from DDB may be

captured to a memory buffer for later inspection using sysctl(8), or in the
future, to a textdump.

A new DDB command, "capture", is added, which accepts arguments "on", "off",
"reset", and "status".

A new DDB sysctl tree, debug.ddb.capture, is added, which can be used to
resize the capture buffer and extract buffer contents.

MFC after:	3 months

1 files changed, 15 insertions, 0 deletions

diff --git a/sys/ddb/ddb.h b/sys/ddb/ddb.h
index 716740b..cb516cc 100644
--- a/sys/ddb/ddb.h
+++ b/sys/ddb/ddb.h
@@ -37,6 +37,10 @@
 #ifndef _DDB_DDB_H_
 #define	_DDB_DDB_H_
 
+#ifdef SYSCTL_DECL
+SYSCTL_DECL(_debug_ddb);
+#endif
+
 #include <machine/db_machdep.h>		/* type definitions */
 
 #ifndef DB_MAXARGS
@@ -126,6 +130,7 @@ int		db_value_of_name(const char *name, db_expr_t *valuep);
 int		db_write_bytes(vm_offset_t addr, size_t size, char *data);
 
 db_cmdfcn_t	db_breakpoint_cmd;
+db_cmdfcn_t	db_capture_cmd;
 db_cmdfcn_t	db_continue_cmd;
 db_cmdfcn_t	db_delete_cmd;
 db_cmdfcn_t	db_deletehwatch_cmd;
@@ -168,4 +173,14 @@ struct command {
 	struct command_table *more; /* another level of command */
 };
 
+/*
+ * Interface between DDB and the DDB output capture facility.
+ */
+struct dumperinfo;
+void	db_capture_dump(struct dumperinfo *di);
+void	db_capture_enterpager(void);
+void	db_capture_exitpager(void);
+void	db_capture_write(char *buffer, u_int buflen);
+void	db_capture_writech(char ch);
+
 #endif /* !_DDB_DDB_H_ */