diff.c: rewrite emit_line_0 more understandably

Rewrite emit_line_0 to have fewer (nested) conditions. The change in 'emit_line' makes sure that 'first' is never user data, but always under our control, a sign or special character in the beginning of the line (or 0, in which case we ignore it). So from now on, let's pass only a diff marker or 0 as the 'first' character of the line. Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Stefan Beller committed Aug 13, 2018 at 18:41 UTC 444106791ee2c4c4575db439ef74d5db5ede6a27
1 file changed +40 -33
diff.c
+40 -33
@@ -626,43 +626,50 @@ static void emit_line_0(struct diff_options *o,
626 int first, const char *line, int len)
627 {
628 int has_trailing_newline, has_trailing_carriage_return;
629 - int nofirst;
629 + int needs_reset = 0; /* at the end of the line */
630 FILE *file = o->file;
631
632 fputs(diff_line_prefix(o), file);
633
634 - if (len == 0) {
635 - has_trailing_newline = (first == '\n');
636 - has_trailing_carriage_return = (!has_trailing_newline &&
637 - (first == '\r'));
638 - nofirst = has_trailing_newline || has_trailing_carriage_return;
639 - } else {
640 - has_trailing_newline = (len > 0 && line[len-1] == '\n');
641 - if (has_trailing_newline)
642 - len--;
643 - has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
644 - if (has_trailing_carriage_return)
645 - len--;
646 - nofirst = 0;
647 - }
648 -
649 - if (len || !nofirst) {
650 - if (reverse && want_color(o->use_color))
651 - fputs(GIT_COLOR_REVERSE, file);
652 - if (set_sign)
653 - fputs(set_sign, file);
654 - if (first && !nofirst)
655 - fputc(first, file);
656 - if (len) {
657 - if (set && set != set_sign) {
658 - if (set_sign)
659 - fputs(reset, file);
660 - fputs(set, file);
661 - }
662 - fwrite(line, len, 1, file);
663 - }
664 - fputs(reset, file);
634 + has_trailing_newline = (len > 0 && line[len-1] == '\n');
635 + if (has_trailing_newline)
636 + len--;
637 +
638 + has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
639 + if (has_trailing_carriage_return)
640 + len--;
641 +
642 + if (!len && !first)
643 + goto end_of_line;
644 +
645 + if (reverse && want_color(o->use_color)) {
646 + fputs(GIT_COLOR_REVERSE, file);
647 + needs_reset = 1;
648 + }
649 +
650 + if (set_sign) {
651 + fputs(set_sign, file);
652 + needs_reset = 1;
653 }
654 +
655 + if (first)
656 + fputc(first, file);
657 +
658 + if (!len)
659 + goto end_of_line;
660 +
661 + if (set) {
662 + if (set_sign && set != set_sign)
663 + fputs(reset, file);
664 + fputs(set, file);
665 + needs_reset = 1;
666 + }
667 + fwrite(line, len, 1, file);
668 + needs_reset = 1; /* 'line' may contain color codes. */
669 +
670 +end_of_line:
671 + if (needs_reset)
672 + fputs(reset, file);
673 if (has_trailing_carriage_return)
674 fputc('\r', file);
675 if (has_trailing_newline)
@@ -672,7 +679,7 @@ static void emit_line_0(struct diff_options *o,
679 static void emit_line(struct diff_options *o, const char *set, const char *reset,
680 const char *line, int len)
681 {
675 - emit_line_0(o, set, NULL, 0, reset, line[0], line+1, len-1);
682 + emit_line_0(o, set, NULL, 0, reset, 0, line, len);
683 }
684
685 enum diff_symbol {