bc: replace G.eof with a special exit code of bc_vm_stdin()

function                                             old     new   delta
bc_read_line                                         305     307      +2
bc_vm_run                                            701     689     -12
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 2/-12)             Total: -10 bytes

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

1 files changed, 9 insertions, 6 deletions

diff --git a/miscutils/bc.c b/miscutils/bc.c
index 2cfe87b1e..24e4b6392 100644
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -191,6 +191,7 @@ typedef enum BcStatus {
 	BC_STATUS_SUCCESS = 0,
 	BC_STATUS_FAILURE = 1,
 	BC_STATUS_PARSE_EMPTY_EXP = 2, // bc_parse_expr() uses this
+	BC_STATUS_EOF = 3, // bc_vm_stdin() uses this
 } BcStatus;
 
 #define BC_VEC_INVALID_IDX ((size_t) -1)
@@ -754,7 +755,6 @@ typedef unsigned long (*BcProgramBuiltIn)(BcNum *);
 struct globals {
 	IF_FEATURE_BC_SIGNALS(smallint ttyin;)
 	IF_FEATURE_CLEAN_UP(smallint exiting;)
-	smallint eof;
 	char sbgn;
 	char send;
 
@@ -1270,10 +1270,12 @@ static int push_input_byte(BcVec *vec, char c)
 
 static BcStatus bc_read_line(BcVec *vec, const char *prompt)
 {
+	BcStatus s;
 	bool bad_chars;
 
 	if (G_posix) prompt = "";
 
+	s = BC_STATUS_SUCCESS;
 	do {
 		int c;
 
@@ -1299,7 +1301,7 @@ static BcStatus bc_read_line(BcVec *vec, const char *prompt)
 			if (n <= 0) { // read errors or EOF, or ^D, or ^C
 				if (n == 0) // ^C
 					goto intr;
-				G.eof = 1;
+				s = BC_STATUS_EOF;
 				break;
 			}
 			i = 0;
@@ -1329,7 +1331,7 @@ static BcStatus bc_read_line(BcVec *vec, const char *prompt)
 				if (c == EOF) {
 					if (ferror(stdin))
 						quit(); // this emits error message
-					G.eof = 1;
+					s = BC_STATUS_EOF;
 					// Note: EOF does not append '\n', therefore:
 					// printf 'print 123\n' | bc - works
 					// printf 'print 123' | bc   - fails (syntax error)
@@ -1342,7 +1344,7 @@ static BcStatus bc_read_line(BcVec *vec, const char *prompt)
 
 	bc_vec_pushZeroByte(vec);
 
-	return BC_STATUS_SUCCESS;
+	return s;
 }
 
 static char* bc_read_file(const char *path)
@@ -7129,8 +7131,7 @@ static BcStatus bc_vm_stdin(void)
 	// with a backslash to the parser. The reason for that is because the parser
 	// treats a backslash+newline combo as whitespace, per the bc spec. In that
 	// case, and for strings and comments, the parser will expect more stuff.
-	s = BC_STATUS_SUCCESS;
-	while (!G.eof && (s = bc_read_line(&buf, ">>> ")) == BC_STATUS_SUCCESS) {
+	while ((s = bc_read_line(&buf, ">>> ")) == BC_STATUS_SUCCESS) {
 
 		char *string = buf.v;
 
@@ -7187,6 +7188,8 @@ static BcStatus bc_vm_stdin(void)
 
 		bc_vec_pop_all(&buffer);
 	}
+	if (s == BC_STATUS_EOF) // input EOF (^D) is not an error
+		s = BC_STATUS_SUCCESS;
 
 	if (str) {
 		s = bc_error("string end could not be found");