[bugfix] Untangle the connection between pr_comment.c and io.c, fixin…

…g at least two bugs.

It's pr_comment.c that should decide whether to put a "star comment continuation" or not. This duplicates code a bit, but it simplifies pr_comment() at the same time since pr_comment() no longer has to "signal" whether a star continuation is needed or not.

This change requires indent(1) to not wrap comment lines that lack a blank character, but I think it's for the better if you look at cases when that happens (mostly long URIs and file system paths, which arguably shouldn't be wrapped).

It also fixes two bugs:

1. Cases where asterisk is a part of the comment's content (like in "*we* are the champions") and happens to appear at the beginning of the line, misleading dump_line() into thinking that this is part of the star comment continuation, leading to misalignment.

2. Cases where blank starred lines had three too many characters on the line when wrapped.

io.c

@@ -242,17 +242,8 @@ dump_line(void)
 		while (e_com > com_st && isspace(e_com[-1]))
 		    e_com--;
 		cur_col = pad_output(cur_col, target);
-		if (!ps.box_com) {
-		    if (star_comment_cont && (com_st[1] != '*' || e_com <= com_st + 1)) {
-			if (com_st[1] == ' ' && com_st[0] == ' ' && e_com > com_st + 1)
-			    com_st[1] = '*';
-			else
-			    fwrite(" * ", isspace((unsigned int) com_st[0]) ? 2 : com_st[0] == '*' ? 1 : 3, 1, output);
-		    }
-		}
 		fwrite(com_st, e_com - com_st, 1, output);
 		ps.comment_delta = ps.n_comment_delta;
-		cur_col = count_spaces(cur_col, com_st);
 		++ps.com_lines;	/* count lines with comments */
 	    }
 	}
@@ -282,7 +273,7 @@ dump_line(void)
     ps.dumped_decl_indent = 0;
     *(e_lab = s_lab) = '\0';	/* reset buffers */
     *(e_code = s_code) = '\0';
-    *(e_com = s_com) = '\0';
+    *(e_com = s_com = combuf + 1) = '\0';
     ps.ind_level = ps.i_l_follow;
     ps.paren_level = ps.p_l_follow;
     if (ps.paren_level > 0)

pr_comment.c

@@ -179,11 +179,11 @@ pr_comment(void)
 	if (blanklines_before_blockcomments)
 	    prefix_blankline_requested = 1;
 	dump_line();
-	e_com = t;
-	s_com[0] = s_com[1] = s_com[2] = ' ';
+	e_com = s_com = t;
+	if (!ps.box_com && star_comment_cont)
+	    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
     }
 
-    *e_com = '\0';
     if (troff) {
 	adj_max_col = 80;
     }
@@ -200,10 +200,10 @@ pr_comment(void)
 		/* fix so dump_line uses a form feed */
 		dump_line();
 		last_bl = NULL;
-		*e_com++ = ' ';
-		*e_com++ = '*';
-		*e_com++ = ' ';
-		while (*++buf_ptr == ' ' || *buf_ptr == '\t');
+		if (!ps.box_com && star_comment_cont)
+		    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
+		while (*++buf_ptr == ' ' || *buf_ptr == '\t')
+		    ;
 	    }
 	    else {
 		if (++buf_ptr >= buf_end)
@@ -215,25 +215,22 @@ pr_comment(void)
 	case '\n':
 	    if (had_eof) {	/* check for unexpected eof */
 		printf("Unterminated comment\n");
-		*e_com = '\0';
 		dump_line();
 		return;
 	    }
 	    last_bl = NULL;
 	    if (ps.box_com || ps.last_nl) {	/* if this is a boxed comment,
 						 * we dont ignore the newline */
-		if (s_com == e_com) {
+		if (s_com == e_com)
 		    *e_com++ = ' ';
-		    *e_com++ = ' ';
-		}
-		*e_com = '\0';
 		if (!ps.box_com && e_com - s_com > 3) {
 		    dump_line();
-		    CHECK_SIZE_COM;
-		    *e_com++ = ' ';
-		    *e_com++ = ' ';
+		    if (star_comment_cont)
+			*e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
 		}
 		dump_line();
+		if (!ps.box_com && star_comment_cont)
+		    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
 	    }
 	    else {
 		ps.last_nl = 1;
@@ -277,20 +274,19 @@ pr_comment(void)
 	end_of_comment:
 		if (++buf_ptr >= buf_end)
 		    fill_buffer();
-		/* ensure blank before end */
-		if (e_com[-1] != ' ' && !ps.box_com) {
-		    *e_com++ = ' ';
-		}
+		CHECK_SIZE_COM;
 		if (break_delim) {
 		    if (e_com > s_com + 3) {
-			*e_com = '\0';
 			dump_line();
 		    }
+		    else
+			s_com = e_com;
+		    *e_com++ = ' ';
 		}
-		CHECK_SIZE_COM;
-		*e_com++ = '*';
-		*e_com++ = '/';
-		*e_com = '\0';
+		if (e_com[-1] != ' ' && !ps.box_com) {
+		    *e_com++ = ' ';	/* ensure blank before end */
+		}
+		*e_com++ = '*', *e_com++ = '/', *e_com = '\0';
 		ps.just_saw_decl = l_just_saw_decl;
 		return;
 	    }
@@ -308,40 +304,29 @@ pr_comment(void)
 		    last_bl = e_com;	/* remember we saw a blank */
 		++e_com;
 		now_col++;
-	    } while (!memchr("*\n\r\b\t", *buf_ptr, 6) && now_col <= adj_max_col);
+	    } while (!memchr("*\n\r\b\t", *buf_ptr, 6) && (now_col <= adj_max_col || !last_bl));
 	    ps.last_nl = false;
 	    if (now_col > adj_max_col && !ps.box_com && e_com[-1] > ' ') {
-		/*
-		 * the comment is too long, it must be broken up
-		 */
-		if (last_bl == NULL) {	/* we have seen no blanks */
-		    last_bl = e_com;	/* fake it */
-		    *e_com++ = ' ';
+		/* the comment is too long, it must be broken up */
+		if (last_bl == NULL) {
+		    dump_line();
+		    if (!ps.box_com && star_comment_cont)
+			*e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
+		    break;
 		}
-		*e_com = '\0';	/* print what we have */
-		*last_bl = '\0';
-		while (last_bl > s_com && last_bl[-1] < 040)
-		    *--last_bl = 0;
+		*e_com = '\0';
 		e_com = last_bl;
 		dump_line();
-
-		*e_com++ = ' ';	/* add blanks for continuation */
-		*e_com++ = ' ';
-		*e_com++ = ' ';
-
-		t_ptr = last_bl + 1;
+		if (!ps.box_com && star_comment_cont)
+		    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
+		for (t_ptr = last_bl + 1; *t_ptr == ' ' || *t_ptr == '\t'; t_ptr++)
+		    ;
 		last_bl = NULL;
-		if (t_ptr >= e_com) {
-		    while (*t_ptr == ' ' || *t_ptr == '\t')
-			t_ptr++;
-		    while (*t_ptr != '\0') {	/* move unprinted part of
-						 * comment down in buffer */
-			if (*t_ptr == ' ' || *t_ptr == '\t')
-			    last_bl = e_com;
-			*e_com++ = *t_ptr++;
-		    }
+		while (*t_ptr != '\0') {
+		    if (*t_ptr == ' ' || *t_ptr == '\t')
+			last_bl = e_com;
+		    *e_com++ = *t_ptr++;
 		}
-		*e_com = '\0';
 	    }
 	    break;
 	}