bc: remove BC_STATUS_EOF (again), the condition is detectable as len==0

function                                             old     new   delta
bc_read_line                                         147     129     -18
bc_vm_run                                            618     591     -27
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-45)             Total: -45 bytes
   text	   data	    bss	    dec	    hex	filename
 980802	    485	   7296	 988583	  f15a7	busybox_old
 980757	    485	   7296	 988538	  f157a	busybox_unstripped

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

diff --git a/miscutils/bc.c b/miscutils/bc.c
index 9cc29f0ea22a39235bea357e19f3b5b5adcbb335..9809fa72f340692372f7966880dbc44a1a033836 100644 (file)
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -187,7 +187,6 @@ typedef enum BcStatus {
        BC_STATUS_SUCCESS = 0,
        BC_STATUS_FAILURE = 1,
        BC_STATUS_PARSE_EMPTY_EXP = 2, // bc_parse_expr_empty_ok() uses this
-       BC_STATUS_EOF = 3, // bc_vm_stdin() uses this
 } BcStatus;
 
 #define BC_VEC_INVALID_IDX ((size_t) -1)
@@ -1364,15 +1363,10 @@ static int push_input_byte(BcVec *vec, char c)
        return 0;
 }
 
-// This is not a "z" function:
-// can return success (0) or BC_STATUS_EOF.
-// Exits with error message if read error is detected.
-static BcStatus bc_read_line(BcVec *vec)
+static void bc_read_line(BcVec *vec)
 {
-       BcStatus s;
        bool bad_chars;
 
-       s = BC_STATUS_SUCCESS;
        do {
                int c;
 
@@ -1397,7 +1391,6 @@ static BcStatus bc_read_line(BcVec *vec)
                        if (n <= 0) { // read errors or EOF, or ^D, or ^C
                                if (n == 0) // ^C
                                        goto intr;
-                               s = BC_STATUS_EOF;
                                break;
                        }
                        i = 0;
@@ -1425,9 +1418,6 @@ static BcStatus bc_read_line(BcVec *vec)
                                if (c == EOF) {
                                        if (ferror(stdin))
                                                quit(); // this emits error message
-                                       // If we had some input before EOF, do not report EOF yet:
-                                       if (vec->len == 0)
-                                               s = BC_STATUS_EOF;
                                        // Note: EOF does not append '\n', therefore:
                                        // printf 'print 123\n' | bc - works
                                        // printf 'print 123' | bc   - fails (syntax error)
@@ -1439,8 +1429,6 @@ static BcStatus bc_read_line(BcVec *vec)
        } while (bad_chars);
 
        bc_vec_pushZeroByte(vec);
-
-       return s;
 }
 
 static char* bc_read_file(const char *path)
@@ -5416,8 +5404,7 @@ static BC_STATUS zbc_program_read(void)
        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
+       bc_read_line(&buf);
 
        common_parse_init(&parse, BC_PROG_READ);
        bc_lex_file(&parse.l);
@@ -7091,13 +7078,18 @@ 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;
        comment = false;
        str = 0;
-       while ((s = bc_read_line(&buf)) == BC_STATUS_SUCCESS) {
+       for (;;) {
                size_t len;
-               char *string = buf.v;
+               char *string;
 
+               bc_read_line(&buf);
                len = buf.len - 1;
+               if (len == 0) // "" buf means EOF
+                       break;
+               string = buf.v;
                if (len == 1) {
                        if (str && buf.v[0] == G.send)
                                str -= 1;
@@ -7146,8 +7138,6 @@ 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");