X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=miscutils%2Fdc.c;h=b922a7184d7d2fe2934662fca61b7ad50dd5cef6;hb=d72e804e6db1bd6eb2417961004b4fe33aba9384;hp=f94d6fa6b301c17119cfe0bcabfc6c227c24e880;hpb=8dff01d06a7ebd7330e3a1dd1ba47b3c74ee7dfb;p=oweals%2Fbusybox.git

diff --git a/miscutils/dc.c b/miscutils/dc.c
index f94d6fa6b..b922a7184 100644
--- a/miscutils/dc.c
+++ b/miscutils/dc.c
@@ -2,9 +2,24 @@
 /*
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
-
-#include "libbb.h"
-#include <math.h>
+//config:config DC
+//config:	bool "dc (4.2 kb)"
+//config:	default y
+//config:	help
+//config:	Dc is a reverse-polish desk calculator which supports unlimited
+//config:	precision arithmetic.
+//config:
+//config:config FEATURE_DC_LIBM
+//config:	bool "Enable power and exp functions (requires libm)"
+//config:	default y
+//config:	depends on DC
+//config:	help
+//config:	Enable power and exp functions.
+//config:	NOTE: This will require libm to be present for linking.
+
+//applet:IF_DC(APPLET(dc, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_DC) += dc.o
 
 //usage:#define dc_trivial_usage
 //usage:       "EXPRESSION..."
@@ -29,6 +44,10 @@
 //usage:       "$ echo 72 9 div 8 mul p | dc\n"
 //usage:       "64\n"
 
+#include "libbb.h"
+#include "common_bufsiz.h"
+#include <math.h>
+
 #if 0
 typedef unsigned data_t;
 #define DATA_FMT ""
@@ -47,15 +66,22 @@ struct globals {
 	double stack[1];
 } FIX_ALIASING;
 enum { STACK_SIZE = (COMMON_BUFSIZE - offsetof(struct globals, stack)) / sizeof(double) };
-#define G (*(struct globals*)&bb_common_bufsiz1)
+#define G (*(struct globals*)bb_common_bufsiz1)
 #define pointer   (G.pointer   )
 #define base      (G.base      )
 #define stack     (G.stack     )
 #define INIT_G() do { \
+	setup_common_bufsiz(); \
 	base = 10; \
 } while (0)
 
 
+static void check_under(void)
+{
+	if (pointer == 0)
+		bb_error_msg_and_die("stack underflow");
+}
+
 static void push(double a)
 {
 	if (pointer >= STACK_SIZE)
@@ -65,8 +91,7 @@ static void push(double a)
 
 static double pop(void)
 {
-	if (pointer == 0)
-		bb_error_msg_and_die("stack underflow");
+	check_under();
 	return stack[--pointer];
 }
 
@@ -187,6 +212,7 @@ static void print_stack_no_pop(void)
 
 static void print_no_pop(void)
 {
+	check_under();
 	print_base(stack[pointer-1]);
 }