Enhance the ddb examine (x) command.

* Change x/a to work similar to gdb.  The content of the memory is
  treated as an address, printed symbolically and the address is advanced.
  This way you can x/a <stack_address> and then just hit return a bunch
  of times to locate useful data on the stack.

* Add x/p.  The content of the memory is treated as an address and
  printed as hex.

This is based on the similar commit from DragonFlyBSD without the
cosmetic changes.

Relnotes:	yes
Obtained from:	DragonflyBSD (Matthew Dillon)
Reference:	0624d20e86affcd708609cbf9014207537537a72

1 files changed, 13 insertions, 10 deletions

diff --git a/sys/ddb/db_examine.c b/sys/ddb/db_examine.c
index a41fcb5..3eff396 100644
--- a/sys/ddb/db_examine.c
+++ b/sys/ddb/db_examine.c
@@ -89,15 +89,6 @@ db_examine(db_addr_t addr, char *fmt, int count)
 		    case 'g':
 			size = 8;
 			break;
-		    case 'a':	/* address */
-			size = sizeof(void *);
-			/* always forces a new line */
-			if (db_print_position() != 0)
-			    db_printf("\n");
-			db_prev = addr;
-			db_printsym(addr, DB_STGY_ANY);
-			db_printf(":\t");
-			break;
 		    default:
 			if (db_print_position() == 0) {
 			    /* Print the address. */
@@ -108,6 +99,18 @@ db_examine(db_addr_t addr, char *fmt, int count)
 
 			width = size * 4;
 			switch (c) {
+			    case 'a':	/* address */
+				size = sizeof(void *);
+				value = db_get_value(addr, size, TRUE);
+				addr += size;
+				db_printsym(value, DB_STGY_ANY);
+				break;
+			    case 'p':
+				size = sizeof(void *);
+				value = db_get_value(addr, size, TRUE);
+				addr += size;
+				db_printf("%p", (void *)value);
+				break;
 			    case 'r':	/* signed, current radix */
 				value = db_get_value(addr, size, true);
 				addr += size;
@@ -173,7 +176,7 @@ db_examine(db_addr_t addr, char *fmt, int count)
 			    default:
 				break;
 			}
-			if (db_print_position() != 0)
+			if (db_print_position() != 0 || c == 'a' || c == 'p')
 			    db_end_line(1);
 			break;
 		}