bc: shrink zbc_vm_stdin()

function                                             old     new   delta
bc_vm_run                                            592     534     -58

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/miscutils/bc.c b/miscutils/bc.c
index 47acd7fc35516ebe1e30249fa43d520de931953c..7ab320a4d334b2ef7a4c3c230feebadc7a6560d8 100644 (file)
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -758,6 +758,7 @@ struct globals {
 # define G_exiting 0
 #endif
 #define IS_BC (ENABLE_BC && (!ENABLE_DC || applet_name[0] == 'b'))
+#define IS_DC (ENABLE_DC && (!ENABLE_BC || applet_name[0] != 'b'))
 
 #if ENABLE_BC
 
@@ -7070,27 +7071,28 @@ static BC_STATUS zbc_vm_stdin(void)
                                str -= 1;
                        else if (buf.v[0] == G.sbgn)
                                str += 1;
-               }
-               else if (len > 1 || comment) {
+               } else {
                        size_t i;
                        for (i = 0; i < len; ++i) {
-                               bool notend = len > i + 1;
                                char c = string[i];
 
                                if (i - 1 > len || string[i - 1] != '\\') {
-                                       if (G.sbgn == G.send)
-                                               str ^= c == G.sbgn;
-                                       else if (c == G.send)
-                                               str -= 1;
-                                       else if (c == G.sbgn)
-                                               str += 1;
+                                       // checking applet type is cheaper than accessing sbgn/send
+                                       if (IS_DC) // dc: sbgn = send = '"'
+                                               str ^= (c == '"');
+                                       else { // bc: sbgn = '[', send = ']'
+                                               if (c == ']')
+                                                       str -= 1;
+                                               else if (c == '[')
+                                                       str += 1;
+                                       }
                                }
 
-                               if (c == '/' && notend && !comment && string[i + 1] == '*') {
+                               if (c == '/' && !comment && string[i + 1] == '*') {
                                        comment = true;
                                        break;
                                }
-                               else if (c == '*' && notend && comment && string[i + 1] == '/')
+                               else if (c == '*' && comment && string[i + 1] == '/')
                                        comment = false;
                        }