Simplify the pager support in DDB. Allowing different db commands to

install custom pager functions didn't actually happen in practice (they
all just used the simple pager and passed in a local quit pointer).  So,
just hardcode the simple pager as the only pager and make it set a global
db_pager_quit flag that db commands can check when the user hits 'q' (or a
suitable variant) at the pager prompt.  Also, now that it's easy to do so,
enable paging by default for all ddb commands.  Any command that wishes to
honor the quit flag can do so by checking db_pager_quit.  Note that the
pager can also be effectively disabled by setting $lines to 0.

Other fixes:
- 'show idt' on i386 and pc98 now actually checks the quit flag and
  terminates early.
- 'show intr' now actually checks the quit flag and terminates early.

3 files changed, 13 insertions, 21 deletions

diff --git a/sys/kern/kern_intr.c b/sys/kern/kern_intr.c
index 042a0ec..7693954 100644
--- a/sys/kern/kern_intr.c
+++ b/sys/kern/kern_intr.c
@@ -905,16 +905,16 @@ db_dump_intr_event(struct intr_event *ie, int handlers)
 DB_SHOW_COMMAND(intr, db_show_intr)
 {
 	struct intr_event *ie;
-	int quit, all, verbose;
+	int all, verbose;
 
-	quit = 0;
 	verbose = index(modif, 'v') != NULL;
 	all = index(modif, 'a') != NULL;
-	db_setup_paging(db_simple_pager, &quit, db_lines_per_page);
 	TAILQ_FOREACH(ie, &event_list, ie_list) {
 		if (!all && TAILQ_EMPTY(&ie->ie_handlers))
 			continue;
 		db_dump_intr_event(ie, verbose);
+		if (db_pager_quit)
+			break;
 	}
 }
 #endif /* DDB */
@@ -976,11 +976,9 @@ DB_SHOW_COMMAND(intrcnt, db_show_intrcnt)
 {
 	u_long *i;
 	char *cp;
-	int quit;
 
 	cp = intrnames;
-	db_setup_paging(db_simple_pager, &quit, db_lines_per_page);
-	for (i = intrcnt, quit = 0; i != eintrcnt && !quit; i++) {
+	for (i = intrcnt; i != eintrcnt && !db_pager_quit; i++) {
 		if (*cp == '\0')
 			break;
 		if (*i != 0)
diff --git a/sys/kern/kern_ktr.c b/sys/kern/kern_ktr.c
index 7ae5582..f12f971 100644
--- a/sys/kern/kern_ktr.c
+++ b/sys/kern/kern_ktr.c
@@ -55,8 +55,10 @@ __FBSDID("$FreeBSD$");
 #include <machine/ktr.h>
 #endif
 
-
+#ifdef DDB
 #include <ddb/ddb.h>
+#include <ddb/db_output.h>
+#endif
 
 #ifndef KTR_ENTRIES
 #define	KTR_ENTRIES	1024
@@ -288,22 +290,17 @@ static	int db_mach_vtrace(void);
 
 DB_SHOW_COMMAND(ktr, db_ktr_all)
 {
-	int quit;
 	
-	quit = 0;
 	tstate.cur = (ktr_idx - 1) & (KTR_ENTRIES - 1);
 	tstate.first = -1;
-	if (strcmp(modif, "v") == 0)
-		db_ktr_verbose = 1;
-	else
-		db_ktr_verbose = 0;
-	if (strcmp(modif, "a") == 0) {
+	db_ktr_verbose = index(modif, 'v') != NULL;
+	if (index(modif, 'a') != NULL) {
+		db_disable_pager();
 		while (cncheckc() != -1)
 			if (db_mach_vtrace() == 0)
 				break;
 	} else {
-		db_setup_paging(db_simple_pager, &quit, db_lines_per_page);
-		while (!quit)
+		while (!db_pager_quit)
 			if (db_mach_vtrace() == 0)
 				break;
 	}
diff --git a/sys/kern/subr_prf.c b/sys/kern/subr_prf.c
index f003bad..12f29b6 100644
--- a/sys/kern/subr_prf.c
+++ b/sys/kern/subr_prf.c
@@ -912,20 +912,17 @@ SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
 
 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
 {
-	int i, j, quit;
-
-	quit = 0;
+	int i, j;
 
 	if (!msgbufmapped) {
 		db_printf("msgbuf not mapped yet\n");
 		return;
 	}
-	db_setup_paging(db_simple_pager, &quit, db_lines_per_page);
 	db_printf("msgbufp = %p\n", msgbufp);
 	db_printf("magic = %x, size = %d, r= %u, w = %u, ptr = %p, cksum= %u\n",
 	    msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_rseq,
 	    msgbufp->msg_wseq, msgbufp->msg_ptr, msgbufp->msg_cksum);
-	for (i = 0; i < msgbufp->msg_size && !quit; i++) {
+	for (i = 0; i < msgbufp->msg_size && !db_pager_quit; i++) {
 		j = MSGBUF_SEQ_TO_POS(msgbufp, i + msgbufp->msg_rseq);
 		db_printf("%c", msgbufp->msg_ptr[j]);
 	}