From src/usr.bin/cvs:

> add changed lines support to log and rlog (the + and - stuff)
> from Pierre Riteau;

3 files changed, 95 insertions, 5 deletions

diff --git a/usr.bin/rcs/rcs.c b/usr.bin/rcs/rcs.c
index c7e2814262d..4c3fa730de6 100644
--- a/usr.bin/rcs/rcs.c
+++ b/usr.bin/rcs/rcs.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rcs.c,v 1.45 2008/01/31 16:36:11 tobias Exp $	*/
+/*	$OpenBSD: rcs.c,v 1.46 2008/02/02 16:21:38 xsa Exp $	*/
 /*
  * Copyright (c) 2004 Jean-Francois Brousseau <jfb@openbsd.org>
  * All rights reserved.
@@ -1277,6 +1277,57 @@ rcs_getrev(RCSFILE *rfp, RCSNUM *frev)
 	return (rbuf);
 }
 
+void
+rcs_delta_stats(struct rcs_delta *rdp, int *ladded, int *lremoved)
+{
+	struct rcs_lines *plines;
+	struct rcs_line *lp;
+	int added, i, lineno, nbln, removed;
+	char op, *ep;
+	u_char tmp;
+
+	added = removed = 0;
+
+	plines = rcs_splitlines(rdp->rd_text, rdp->rd_tlen);
+	lp = TAILQ_FIRST(&(plines->l_lines));
+
+	/* skip first bogus line */
+	for (lp = TAILQ_NEXT(lp, l_list); lp != NULL;
+		lp = TAILQ_NEXT(lp, l_list)) {
+			if (lp->l_len < 2)
+				errx(1,
+				    "line too short, RCS patch seems broken");
+			op = *(lp->l_line);
+			/* NUL-terminate line buffer for strtol() safety. */
+			tmp = lp->l_line[lp->l_len - 1];
+			lp->l_line[lp->l_len - 1] = '\0';
+			lineno = (int)strtol((lp->l_line + 1), &ep, 10);
+			ep++;
+			nbln = (int)strtol(ep, &ep, 10);
+			/* Restore the last byte of the buffer */
+			lp->l_line[lp->l_len - 1] = tmp;
+			if (nbln < 0)
+				errx(1, "invalid line number specification "
+				    "in RCS patch");
+
+			if (op == 'a') {
+				added += nbln;
+				for (i = 0; i < nbln; i++) {
+					lp = TAILQ_NEXT(lp, l_list);
+					if (lp == NULL)
+						errx(1, "truncated RCS patch");
+				}
+			} else if (op == 'd')
+				removed += nbln;
+			else
+				errx(1, "unknown RCS patch operation '%c'", op);
+	}
+
+	*ladded = added;
+	*lremoved = removed;
+}
+ 	 
+
 /*
  * rcs_rev_add()
  *
diff --git a/usr.bin/rcs/rcs.h b/usr.bin/rcs/rcs.h
index 9f279ea8764..6e82ae5ed66 100644
--- a/usr.bin/rcs/rcs.h
+++ b/usr.bin/rcs/rcs.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rcs.h,v 1.7 2008/01/31 16:36:11 tobias Exp $	*/
+/*	$OpenBSD: rcs.h,v 1.8 2008/02/02 16:21:38 xsa Exp $	*/
 /*
  * Copyright (c) 2004 Jean-Francois Brousseau <jfb@openbsd.org>
  * All rights reserved.
@@ -253,6 +253,7 @@ int			 rcs_state_check(const char *);
 RCSNUM			*rcs_tag_resolve(RCSFILE *, const char *);
 const char		*rcs_errstr(int);
 void			 rcs_write(RCSFILE *);
+void			 rcs_delta_stats(struct rcs_delta *, int *, int *);
 
 int	rcs_kflag_get(const char *);
 void	rcs_kflag_usage(void);
diff --git a/usr.bin/rcs/rlog.c b/usr.bin/rcs/rlog.c
index 4f3d0f35abc..6b904ef56d4 100644
--- a/usr.bin/rcs/rlog.c
+++ b/usr.bin/rcs/rlog.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rlog.c,v 1.59 2007/09/09 17:01:38 ray Exp $	*/
+/*	$OpenBSD: rlog.c,v 1.60 2008/02/02 16:21:38 xsa Exp $	*/
 /*
  * Copyright (c) 2005 Joris Vink <joris@openbsd.org>
  * Copyright (c) 2005, 2006 Xavier Santolaria <xsa@openbsd.org>
@@ -262,6 +262,8 @@ rlog_rev_print(struct rcs_delta *rdp)
 	struct tm t;
 	char *author, numb[RCS_REV_BUFSZ], *fmt, timeb[RCS_TIME_BUFSZ];
 	struct rcs_argvector *largv, *sargv, *wargv;
+	struct rcs_branch *rb;
+	struct rcs_delta *nrdp;
 
 	i = found = 0;
 	author = NULL;
@@ -347,10 +349,46 @@ rlog_rev_print(struct rcs_delta *rdp)
 		fmt = "%Y/%m/%d %H:%M:%S";
 	}
 
-	strftime(timeb, sizeof(timeb), fmt, &t);
+	(void)strftime(timeb, sizeof(timeb), fmt, &t);
 
-	printf("\ndate: %s;  author: %s;  state: %s;\n", timeb, rdp->rd_author,
+	printf("\ndate: %s;  author: %s;  state: %s;", timeb, rdp->rd_author,
 	    rdp->rd_state);
 
+	/*
+	 * If we are a branch revision, the diff of this revision is stored
+	 * in place.
+	 * Otherwise, it is stored in the previous revision as a reversed diff.
+	 */
+	if (RCSNUM_ISBRANCHREV(rdp->rd_num))
+		nrdp = rdp;
+	else
+		nrdp = TAILQ_NEXT(rdp, rd_list);
+ 	 
+	/*
+	 * We do not write diff stats for the first revision of the default
+	 * branch, since it was not a diff but a full text.
+	 */
+	if (nrdp != NULL && rdp->rd_num->rn_len == nrdp->rd_num->rn_len) {
+		int added, removed;
+		rcs_delta_stats(nrdp, &added, &removed);
+		if (RCSNUM_ISBRANCHREV(rdp->rd_num))
+			printf("  lines: +%d -%d", added, removed);
+		else
+			printf("  lines: +%d -%d", removed, added);
+		}
+		printf("\n");
+ 
+		if (!TAILQ_EMPTY(&(rdp->rd_branches))) {
+			printf("branches:");
+			TAILQ_FOREACH(rb, &(rdp->rd_branches), rb_list) {
+				RCSNUM *branch;
+				branch = rcsnum_revtobr(rb->rb_num);
+				(void)rcsnum_tostr(branch, numb, sizeof(numb));
+				printf("  %s;", numb);
+				rcsnum_free(branch);
+			}
+			printf("\n");
+		}
+
 	printf("%s", rdp->rd_log);
 }