bc: simplify nested read() check

function                                             old     new   delta
bc_vm_run                                            622     624      +2
dc_main                                              186     187      +1
bc_main                                               72      73      +1
bc_program_read                                      312     277     -35
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/1 up/down: 4/-35)             Total: -31 bytes

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

1 files changed, 7 insertions, 7 deletions

diff --git a/miscutils/bc.c b/miscutils/bc.c
index 70db2ce3d..791275c8c 100644
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -736,6 +736,7 @@ typedef struct BcProgram {
 struct globals {
         IF_FEATURE_BC_SIGNALS(smallint ttyin;)
         IF_FEATURE_CLEAN_UP(smallint exiting;)
+        smallint in_read;
         char sbgn;
         char send;
 
@@ -5390,20 +5391,18 @@ static BcStatus bc_program_read(void)
         BcParse parse;
         BcVec buf;
         BcInstPtr ip;
-        size_t i;
-        BcFunc *f = bc_program_func(BC_PROG_READ);
+        BcFunc *f;
 
-        for (i = 0; i < G.prog.stack.len; ++i) {
-                BcInstPtr *ip_ptr = bc_vec_item(&G.prog.stack, i);
-                if (ip_ptr->func == BC_PROG_READ)
-                        return bc_error_nested_read_call();
-        }
+        if (G.in_read)
+                return bc_error_nested_read_call();
 
+        f = bc_program_func(BC_PROG_READ);
         bc_vec_pop_all(&f->code);
         bc_char_vec_init(&buf);
 
         sv_file = G.prog.file;
         G.prog.file = NULL;
+        G.in_read = 1;
 
         s = bc_read_line(&buf);
         //if (s) goto io_err; - wrong, nonzero return means EOF, not error
@@ -5434,6 +5433,7 @@ static BcStatus bc_program_read(void)
 exec_err:
         bc_parse_free(&parse);
 //io_err:
+        G.in_read = 0;
         G.prog.file = sv_file;
         bc_vec_free(&buf);
         return s;