bc: fix empty lines in dc generating "bad token" message

function                                             old     new   delta
zdc_program_asciify                                    -     370    +370
zbc_program_pushArray                                  -     147    +147
zbc_vm_process                                       824     828      +4
zbc_program_exec                                    4182    4046    -136
zdc_program_printStream                              146       -    -146
zbc_program_read                                     268       -    -268
------------------------------------------------------------------------------
(add/remove: 2/2 grow/shrink: 1/1 up/down: 521/-550)          Total: -29 bytes

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

1 files changed, 10 insertions, 8 deletions

diff --git a/miscutils/bc.c b/miscutils/bc.c
index 25150a9eb..a7b8aa4bb 100644
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -6695,9 +6695,18 @@ static BC_STATUS zbc_vm_process(const char *text)
 // "print 1" part.
                         IF_BC(s = zbc_parse_stmt_or_funcdef(&G.prs));
                 } else {
+                        // Most of dc parsing assumes all whitespace,
+                        // including '\n', is eaten.
+                        while (G.prs.l.t.t == BC_LEX_NLINE) {
+                                s = zbc_lex_next(&G.prs.l);
+                                if (s) goto err;
+                                if (G.prs.l.t.t == BC_LEX_EOF)
+                                        goto done;
+                        }
                         IF_DC(s = zdc_parse_expr(&G.prs));
                 }
                 if (s || G_interrupt) {
+ err:
                         bc_parse_reset(&G.prs); // includes bc_program_reset()
                         RETURN_STATUS(BC_STATUS_FAILURE);
                 }
@@ -6735,13 +6744,6 @@ static BC_STATUS zbc_vm_process(const char *text)
                         IF_BC(bc_vec_pop_all(&f->strs);)
                         IF_BC(bc_vec_pop_all(&f->consts);)
                 } else {
-                        // Most of dc parsing assumes all whitespace,
-                        // including '\n', is eaten.
-                        if (G.prs.l.t.t == BC_LEX_NLINE) {
-                                s = zbc_lex_next(&G.prs.l);
-                                if (s) RETURN_STATUS(s);
-                        }
-
                         if (G.prog.results.len == 0
                          && G.prog.vars.len == 0
                         ) {
@@ -6762,7 +6764,7 @@ static BC_STATUS zbc_vm_process(const char *text)
                 bc_vec_pop_all(&f->code);
                 ip->inst_idx = 0;
         }
-
+ done:
         dbg_lex_done("%s:%d done", __func__, __LINE__);
         RETURN_STATUS(s);
 }