With this commit, I hereby pronounce gensetdefs past its use-by date.

Replace the a.out emulation of 'struct linker_set' with something
a little more flexible.  <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.

The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).

The macros declare a strongly typed set.  They return elements with the
type that you declare the set with, rather than a generic void *.

For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>).  Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.

For a.out, we use the old linker_set struct.

NOTE: the item lists are no longer null terminated.  This is why
the code impact is high in certain areas.

The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.

linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.

Reviewed by:	eivind

1 files changed, 22 insertions, 14 deletions

diff --git a/sys/ddb/db_command.c b/sys/ddb/db_command.c
index 201d1f1..39378e9 100644
--- a/sys/ddb/db_command.c
+++ b/sys/ddb/db_command.c
@@ -51,13 +51,14 @@
  * Exported global variables
  */
 boolean_t	db_cmd_loop_done;
-extern struct linker_set	db_cmd_set;
 db_addr_t	db_dot;
 jmp_buf		db_jmpbuf;
 db_addr_t	db_last_addr;
 db_addr_t	db_prev;
 db_addr_t	db_next;
-extern struct linker_set	db_show_cmd_set;
+
+SET_DECLARE(db_cmd_set, struct command);
+SET_DECLARE(db_show_cmd_set, struct command);
 
 static db_cmdfcn_t	db_fncall;
 static db_cmdfcn_t	db_gdb;
@@ -94,22 +95,26 @@ db_skip_to_eol()
 #define	CMD_HELP	4
 
 static void	db_cmd_list __P((struct command *table,
-				 struct command **aux_tablep));
+				 struct command **aux_tablep,
+				 struct command **aux_tablep_end));
 static int	db_cmd_search __P((char *name, struct command *table,
 				   struct command **aux_tablep,
+				   struct command **aux_tablep_end,
 				   struct command **cmdp));
 static void	db_command __P((struct command **last_cmdp,
 				struct command *cmd_table,
-				struct command **aux_cmd_tablep));
+				struct command **aux_cmd_tablep,
+				struct command **aux_cmd_tablep_end));
 
 /*
  * Search for command prefix.
  */
 static int
-db_cmd_search(name, table, aux_tablep, cmdp)
+db_cmd_search(name, table, aux_tablep, aux_tablep_end, cmdp)
 	char *		name;
 	struct command	*table;
 	struct command	**aux_tablep;
+	struct command	**aux_tablep_end;
 	struct command	**cmdp;	/* out */
 {
 	struct command	*cmd;
@@ -148,7 +153,7 @@ db_cmd_search(name, table, aux_tablep, cmdp)
 	}
 	if (result == CMD_NONE && aux_tablep != 0)
 	    /* XXX repeat too much code. */
-	    for (aux_cmdp = aux_tablep; *aux_cmdp != 0; aux_cmdp++) {
+	    for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) {
 		register char *lp;
 		register char *rp;
 		register int  c;
@@ -188,9 +193,10 @@ db_cmd_search(name, table, aux_tablep, cmdp)
 }
 
 static void
-db_cmd_list(table, aux_tablep)
+db_cmd_list(table, aux_tablep, aux_tablep_end)
 	struct command *table;
 	struct command **aux_tablep;
+	struct command **aux_tablep_end;
 {
 	register struct command *cmd;
 	register struct command **aux_cmdp;
@@ -201,17 +207,18 @@ db_cmd_list(table, aux_tablep)
 	}
 	if (aux_tablep == 0)
 	    return;
-	for (aux_cmdp = aux_tablep; *aux_cmdp != 0; aux_cmdp++) {
+	for (aux_cmdp = aux_tablep; aux_cmdp < aux_tablep_end; aux_cmdp++) {
 	    db_printf("%-12s", (*aux_cmdp)->name);
 	    db_end_line();
 	}
 }
 
 static void
-db_command(last_cmdp, cmd_table, aux_cmd_tablep)
+db_command(last_cmdp, cmd_table, aux_cmd_tablep, aux_cmd_tablep_end)
 	struct command	**last_cmdp;	/* IN_OUT */
 	struct command	*cmd_table;
 	struct command	**aux_cmd_tablep;
+	struct command	**aux_cmd_tablep_end;
 {
 	struct command	*cmd;
 	int		t;
@@ -246,6 +253,7 @@ db_command(last_cmdp, cmd_table, aux_cmd_tablep)
 		result = db_cmd_search(db_tok_string,
 				       cmd_table,
 				       aux_cmd_tablep,
+				       aux_cmd_tablep_end,
 				       &cmd);
 		switch (result) {
 		    case CMD_NONE:
@@ -257,7 +265,7 @@ db_command(last_cmdp, cmd_table, aux_cmd_tablep)
 			db_flush_lex();
 			return;
 		    case CMD_HELP:
-			db_cmd_list(cmd_table, aux_cmd_tablep);
+			db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end);
 			db_flush_lex();
 			return;
 		    default:
@@ -267,12 +275,12 @@ db_command(last_cmdp, cmd_table, aux_cmd_tablep)
 		    /* XXX usually no more aux's. */
 		    aux_cmd_tablep = 0;
 		    if (cmd_table == db_show_cmds)
-			aux_cmd_tablep =
-			    (struct command **)&db_show_cmd_set.ls_items[0];
+			aux_cmd_tablep = SET_BEGIN(db_show_cmd_set);
+			aux_cmd_tablep_end = SET_LIMIT(db_show_cmd_set);
 
 		    t = db_read_token();
 		    if (t != tIDENT) {
-			db_cmd_list(cmd_table, aux_cmd_tablep);
+			db_cmd_list(cmd_table, aux_cmd_tablep, aux_cmd_tablep_end);
 			db_flush_lex();
 			return;
 		    }
@@ -453,7 +461,7 @@ db_command_loop()
 	    (void) db_read_line();
 
 	    db_command(&db_last_command, db_command_table,
-		       (struct command **)&db_cmd_set.ls_items[0]);
+		       SET_BEGIN(db_cmd_set), SET_LIMIT(db_cmd_set));
 	}
 }