Implement \$ and \# expansion for PS1. Whoever thought it a clever

idea to assign a special meaning to "\$" -- two chars that are already
(very) special -- deserves a spanking.

4 files changed, 28 insertions, 16 deletions

diff --git a/bin/ksh/history.c b/bin/ksh/history.c
index bcd7ee6fbf3..d7f38e152c1 100644
--- a/bin/ksh/history.c
+++ b/bin/ksh/history.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: history.c,v 1.34 2006/03/17 16:30:13 millert Exp $	*/
+/*	$OpenBSD: history.c,v 1.35 2006/05/29 18:22:24 otto Exp $	*/
 
 /*
  * command history
@@ -851,6 +851,7 @@ histload(Source *s, unsigned char *base, int bytes)
 				}
 				else {
 					s->line = lno;
+					s->cmd_offset = lno;
 					histsave(lno, (char *)line, 0);
 				}
 				state = shdr;
diff --git a/bin/ksh/ksh.1 b/bin/ksh/ksh.1
index 2714ada803f..7c43779fc8d 100644
--- a/bin/ksh/ksh.1
+++ b/bin/ksh/ksh.1
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ksh.1,v 1.112 2006/04/22 14:10:36 jmc Exp $
+.\"	$OpenBSD: ksh.1,v 1.113 2006/05/29 18:22:24 otto Exp $
 .\"
 .\"	Public Domain
 .\"
@@ -1634,7 +1634,6 @@ The current history number
 (see
 .Sq \e# ,
 below).
-Note: this sequence is not yet implemented.
 .It Li \e#
 The current command number.
 This could be different to the current history number,
@@ -1647,7 +1646,6 @@ The default prompt i.e.\&
 if the effective UID is 0,
 otherwise
 .Sq $ \& .
-Note: this sequence is not yet implemented.
 .It Li \e Ns Ar nnn
 The octal character
 .Ar nnn .
diff --git a/bin/ksh/lex.c b/bin/ksh/lex.c
index 860c6bf1365..db5392f434f 100644
--- a/bin/ksh/lex.c
+++ b/bin/ksh/lex.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lex.c,v 1.39 2006/04/10 14:38:59 jaredy Exp $	*/
+/*	$OpenBSD: lex.c,v 1.40 2006/05/29 18:22:24 otto Exp $	*/
 
 /*
  * lexical analysis and source input
@@ -63,6 +63,7 @@ static const char *ungetsc(int);
 static void	gethere(void);
 static Lex_state *push_state_(State_info *, Lex_state *);
 static Lex_state *pop_state_(State_info *, Lex_state *);
+static char	*special_prompt_expand(char *);
 static int	dopprompt(const char *, int, const char **, int);
 
 static int backslash_skip;
@@ -909,6 +910,7 @@ pushs(int type, Area *areap)
 	s->str = null;
 	s->start = NULL;
 	s->line = 0;
+	s->cmd_offset = 0;
 	s->errline = 0;
 	s->file = NULL;
 	s->flags = 0;
@@ -1120,6 +1122,18 @@ getsc_line(Source *s)
 		set_prompt(PS2, (Source *) 0);
 }
 
+static char *
+special_prompt_expand(char *str)
+{
+	char *p = str;
+
+	while ((p = strstr(p, "\\$")) != NULL) {
+		memmove(p, p + 1, strlen(p));
+		*p = ksheuid ? '$' : '#';
+	}
+	return str;
+}
+
 void
 set_prompt(int to, Source *s)
 {
@@ -1141,9 +1155,11 @@ set_prompt(int to, Source *s)
 			 * unwinding its stack through this code as it
 			 * exits.
 			 */
-		} else
-			prompt = str_save(substitute(ps1, 0),
-			    saved_atemp);
+		} else {
+			/* expand \$ before other substitutions are done */
+			char *tmp = special_prompt_expand(ps1);
+			prompt = str_save(substitute(tmp, 0), saved_atemp);
+		}
 		quitenv(NULL);
 		break;
 	case PS2: /* command continuation */
@@ -1309,17 +1325,13 @@ dopprompt(const char *sp, int ntruncate, const char **spp, int doprint)
 				p = str_val(global("PWD"));
 				strlcpy(strbuf, basename(p), sizeof strbuf);
 				break;
-			case '!':	/* '\' '!' history line number XXX busted */
+			case '!':	/* '\' '!' history line number */
 				snprintf(strbuf, sizeof strbuf, "%d",
 				    source->line + 1);
 				break;
-			case '#':	/* '\' '#' command line number XXX busted */
+			case '#':	/* '\' '#' command line number */
 				snprintf(strbuf, sizeof strbuf, "%d",
-				    source->line + 1);
-				break;
-			case '$':	/* '\' '$' $ or # XXX busted */
-				strbuf[0] = ksheuid ? '$' : '#';
-				strbuf[1] = '\0';
+				    source->line - source->cmd_offset + 1);
 				break;
 			case '0':	/* '\' '#' '#' ' #' octal numeric handling */
 			case '1':
diff --git a/bin/ksh/lex.h b/bin/ksh/lex.h
index 82cadf151f0..0904fbda1d9 100644
--- a/bin/ksh/lex.h
+++ b/bin/ksh/lex.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lex.h,v 1.10 2005/09/11 18:02:27 otto Exp $	*/
+/*	$OpenBSD: lex.h,v 1.11 2006/05/29 18:22:24 otto Exp $	*/
 
 /*
  * Source input, lexer and parser
@@ -22,6 +22,7 @@ struct source {
 	char	ugbuf[2];	/* buffer for ungetsc() (SREREAD) and
 				 * alias (SALIAS) */
 	int	line;		/* line number */
+	int	cmd_offset;	/* line number - command number */
 	int	errline;	/* line the error occurred on (0 if not set) */
 	const char *file;	/* input file name */
 	int	flags;		/* SF_* */