PERFORCE change 34250 for review

[John Baldwin]

http://perforce.freebsd.org/chv.cgi?CH=34250

Change 34250 by jhb at jhb_laptop on 2003/07/09 10:58:01

	First cut at adding generic pager support into ddb's output
	routines.  Convert 'ps' to use this method.  By the way, I
	think it would be a good idea if ps just showed procs and a
	separate 'show threads' command showed actual threads.  This
	is how mach does things apparently.

Affected files ...

.. //depot/projects/smpng/sys/ddb/db_command.c#13 edit
.. //depot/projects/smpng/sys/ddb/db_output.c#4 edit
.. //depot/projects/smpng/sys/ddb/db_ps.c#21 edit
.. //depot/projects/smpng/sys/ddb/ddb.h#8 edit

Differences ...

==== //depot/projects/smpng/sys/ddb/db_command.c#13 (text+ko) ====

@@ -343,7 +343,9 @@
 	    /*
 	     * Execute the command.
 	     */
+	    db_setup_paging(NULL, NULL, -1);
 	    (*cmd->fcn)(addr, have_addr, count, modif);
+	    db_setup_paging(NULL, NULL, -1);
 
 	    if (cmd->flag & CS_SET_DOT) {
 		/*

==== //depot/projects/smpng/sys/ddb/db_output.c#4 (text+ko) ====

@@ -62,6 +62,10 @@
 #define	NEXT_TAB(i) \
 	((((i) + db_tab_stop_width) / db_tab_stop_width) * db_tab_stop_width)
 db_expr_t	db_max_width = 79;		/* output line width */
+static int	db_newlines = 0;		/* # lines this page */
+static int	db_maxlines = -1;		/* max lines per page */
+static db_page_calloutfcn_t *db_page_callout = NULL;
+static void	*db_page_callout_arg = NULL;
 
 static void db_putchar(int c, void *arg);
 
@@ -98,6 +102,7 @@
 	int	c;		/* character to output */
 	void *	arg;
 {
+
 	if (c > ' ' && c <= '~') {
 	    /*
 	     * Printing character.
@@ -115,6 +120,14 @@
 	    db_output_position = 0;
 	    db_last_non_space = 0;
 	    db_check_interrupt();
+	    if (db_maxlines > 0 && db_page_callout != NULL) {
+		    db_newlines++;
+		    if (db_newlines >= db_maxlines) {
+			    db_maxlines = -1;
+			    db_page_callout(db_page_callout_arg);
+			    db_newlines = 0;
+		    }
+	    }
 	}
 	else if (c == '\r') {
 	    /* Return */
@@ -139,6 +152,56 @@
 }
 
 /*
+ * Register callout for providing a pager for output.
+ */
+void
+db_setup_paging(db_page_calloutfcn_t *callout, void *arg, int maxlines)
+{
+
+	db_page_callout = callout;
+	db_page_callout_arg = arg;
+	db_maxlines = maxlines;
+}
+
+/*
+ * A simple paging callout function.  If the argument is not null, it
+ * points to an integer that will be set to 1 if the user asks to quit.
+ */
+void
+db_simple_pager(void *arg)
+{
+	int c;
+
+	db_printf("--More--\r");
+	for (;;) {
+		c = cngetc();
+		switch (c) {
+		case '\n':
+			/* Just one more line. */
+			db_setup_paging(db_simple_pager, arg, 1);
+			return;
+		case ' ':
+			/* Another page. */
+			db_setup_paging(db_simple_pager, arg,
+			    DB_LINES_PER_PAGE);
+			return;
+		case 'q':
+		case 'Q':
+		case 'x':
+		case 'X':
+			/* Quit */
+			if (arg != NULL) {
+				*(int *)arg = 1;
+				return;
+			}
+			/* FALLTHROUGH */
+		default:
+			cnputc('\007');
+		}
+	}
+}
+
+/*
  * Return output position
  */
 int

==== //depot/projects/smpng/sys/ddb/db_ps.c#21 (text+ko) ====

@@ -55,13 +55,13 @@
 	db_expr_t	dummy3;
 	char *		dummy4;
 {
-	int np;
-	int nl = 0;
 	volatile struct proc *p, *pp;
 	volatile struct thread *td;
 	char *state;
+	int np, quit;
 
 	np = nprocs;
+	quit = 0;
 
 	/* sx_slock(&allproc_lock); */
 	if (!LIST_EMPTY(&allproc))
@@ -69,32 +69,9 @@
 	else
 		p = &proc0;
 
+	db_setup_paging(db_simple_pager, &quit, DB_LINES_PER_PAGE);
 	db_printf("  pid   proc     addr    uid  ppid  pgrp  flag   stat  wmesg    wchan  cmd\n");
-	while (--np >= 0) {
-		/*
-		 * XXX just take 20 for now...
-		 */
-		if (nl++ >= 20) {
-			int c;
-
-			db_printf("--More--");
-			c = cngetc();
-			db_printf("\r");
-			/*
-			 * A whole screenfull or just one line?
-			 */
-			switch (c) {
-			case '\n':		/* just one line */
-				nl = 20;
-				break;
-			case ' ':
-				nl = 0;		/* another screenfull */
-				break;
-			default:		/* exit */
-				db_printf("\n");
-				return;
-			}
-		}
+	while (--np >= 0 && !quit) {
 		if (p == NULL) {
 			printf("oops, ran out of processes early!\n");
 			break;
@@ -131,7 +108,8 @@
 			db_printf("(threaded)  %s\n", p->p_comm);
 		FOREACH_THREAD_IN_PROC(p, td) {
 			dumpthread(p, td);
-			nl++;
+			if (quit)
+				break;
 		}
 		/* PROC_UNLOCK(p); */
 
@@ -145,6 +123,7 @@
 static void
 dumpthread(volatile struct proc *p, volatile struct thread *td)
 {
+
 	if (p->p_flag & P_SA) 
 		db_printf( "   thread %p ksegrp %p ", td, td->td_ksegrp);
 	if (TD_ON_SLEEPQ(td)) {

==== //depot/projects/smpng/sys/ddb/ddb.h#8 (text+ko) ====

@@ -39,9 +39,13 @@
 
 #include <machine/db_machdep.h>		/* type definitions */
 
+#define	DB_LINES_PER_PAGE	20
+
 typedef void db_cmdfcn_t(db_expr_t addr, boolean_t have_addr, db_expr_t count,
 	    char *modif);
 
+typedef void db_page_calloutfcn_t(void *arg);
+
 #define DB_COMMAND(cmd_name, func_name) \
 	DB_SET(cmd_name, func_name, db_cmd_set, 0, NULL)
 #define DB_SHOW_COMMAND(cmd_name, func_name) \
@@ -100,6 +104,8 @@
 int		db_readline(char *lstart, int lsize);
 void		db_restart_at_pc(boolean_t watchpt);
 void		db_set_watchpoints(void);
+void		db_setup_paging(db_page_calloutfcn_t *callout, void *arg,
+				int maxlines);
 void		db_skip_to_eol(void);
 boolean_t	db_stop_at_pc(boolean_t *is_breakpoint);
 #define		db_strcpy	strcpy
@@ -139,6 +145,8 @@
 db_cmdfcn_t	vm_page_print;
 #endif
 
+db_page_calloutfcn_t db_simple_pager;
+
 /* Scare the user with backtrace of curthread to console. */
 void		db_print_backtrace(void);