4 files changed, 61 insertions, 8 deletions

diff --git a/usr.bin/sed/defs.h b/usr.bin/sed/defs.h
index d4f434ee84ebf..fb336765d639b 100644
--- a/usr.bin/sed/defs.h
+++ b/usr.bin/sed/defs.h
@@ -143,6 +143,7 @@ typedef struct {
 	char *space;		/* Current space pointer. */
 	size_t len;		/* Current length. */
 	int deleted;		/* If deleted. */
+	int append_newline;	/* If originally terminated by \n. */
 	char *back;		/* Backing memory. */
 	size_t blen;		/* Backing memory length. */
 } SPACE;
diff --git a/usr.bin/sed/main.c b/usr.bin/sed/main.c
index 6cdfcda936787..76e186f96b8a5 100644
--- a/usr.bin/sed/main.c
+++ b/usr.bin/sed/main.c
@@ -439,8 +439,14 @@ mf_fgets(SPACE *sp, enum e_spflag spflag)
 	len = getline(&p, &plen, infile);
 	if (len == -1)
 		err(1, "%s", fname);
-	if (len != 0 && p[len - 1] == '\n')
+	if (len != 0 && p[len - 1] == '\n') {
+		sp->append_newline = 1;
 		len--;
+	} else if (!lastline()) {
+		sp->append_newline = 1;
+	} else {
+		sp->append_newline = 0;
+	}
 	cspace(sp, p, len, spflag);
 
 	linenum++;
@@ -481,15 +487,49 @@ add_file(char *s)
 	fl_nextp = &fp->next;
 }
 
+static int
+next_files_have_lines()
+{
+	struct s_flist *file;
+	FILE *file_fd;
+	int ch;
+
+	file = files;
+	while ((file = file->next) != NULL) {
+		if ((file_fd = fopen(file->fname, "r")) == NULL)
+			continue;
+
+		if ((ch = getc(file_fd)) != EOF) {
+			/*
+			 * This next file has content, therefore current
+			 * file doesn't contains the last line.
+			 */
+			ungetc(ch, file_fd);
+			fclose(file_fd);
+			return (1);
+		}
+
+		fclose(file_fd);
+	}
+
+	return (0);
+}
+
 int
 lastline(void)
 {
 	int ch;
 
-	if (files->next != NULL && (inplace == NULL || ispan))
-		return (0);
-	if ((ch = getc(infile)) == EOF)
-		return (1);
+	if (feof(infile)) {
+		return !(
+		    (inplace == NULL || ispan) &&
+		    next_files_have_lines());
+	}
+	if ((ch = getc(infile)) == EOF) {
+		return !(
+		    (inplace == NULL || ispan) &&
+		    next_files_have_lines());
+	}
 	ungetc(ch, infile);
 	return (0);
 }
diff --git a/usr.bin/sed/process.c b/usr.bin/sed/process.c
index a500200dd87d0..9cd2c2e87b24d 100644
--- a/usr.bin/sed/process.c
+++ b/usr.bin/sed/process.c
@@ -63,6 +63,7 @@ static SPACE HS, PS, SS, YS;
 #define	pd		PS.deleted
 #define	ps		PS.space
 #define	psl		PS.len
+#define	psanl		PS.append_newline
 #define	hs		HS.space
 #define	hsl		HS.len
 
@@ -85,7 +86,10 @@ static regex_t *defpreg;
 size_t maxnsub;
 regmatch_t *match;
 
-#define OUT() do {fwrite(ps, 1, psl, outfile); fputc('\n', outfile);} while (0)
+#define OUT() do {							\
+	fwrite(ps, 1, psl, outfile);					\
+	if (psanl) fputc('\n', outfile);				\
+} while (0)
 
 void
 process(void)
@@ -94,6 +98,7 @@ process(void)
 	SPACE tspace;
 	size_t oldpsl = 0;
 	char *p;
+	int oldpsanl;
 
 	p = NULL;
 
@@ -190,11 +195,15 @@ redirect:
 					break;
 				if ((p = memchr(ps, '\n', psl)) != NULL) {
 					oldpsl = psl;
+					oldpsanl = psanl;
 					psl = p - ps;
+					psanl = 1;
 				}
 				OUT();
-				if (p != NULL)
+				if (p != NULL) {
 					psl = oldpsl;
+					psanl = oldpsanl;
+				}
 				break;
 			case 'q':
 				if (!nflag && !pd)
@@ -244,6 +253,7 @@ redirect:
 					cspace(&HS, "", 0, REPLACE);
 				tspace = PS;
 				PS = HS;
+				psanl = tspace.append_newline;
 				HS = tspace;
 				break;
 			case 'y':
@@ -452,6 +462,7 @@ substitute(struct s_command *cp)
 	 */
 	tspace = PS;
 	PS = SS;
+	psanl = tspace.append_newline;
 	SS = tspace;
 	SS.space = SS.back;
 
@@ -521,6 +532,7 @@ do_tr(struct s_tr *y)
 		/* Swap the translation space and the pattern space. */
 		tmp = PS;
 		PS = YS;
+		psanl = tmp.append_newline;
 		YS = tmp;
 		YS.space = YS.back;
 	}
diff --git a/usr.bin/sed/tests/regress.y.out b/usr.bin/sed/tests/regress.y.out
index 829a681802766..22f4f051cef18 100644
--- a/usr.bin/sed/tests/regress.y.out
+++ b/usr.bin/sed/tests/regress.y.out
@@ -1 +1 @@
-fOO
+fOO
\ No newline at end of file