* lib.c (simple_lazy_stream_func): Bugfix: close the stream

if get_line returns nil.

* stream.c (cat_get_line, cat_get_char, cat_get_byte): The catenated
stream read operations close an exhausted stream before popping
to the next one.

* txr.1: Document closing behavior of catenated streams.

4 files changed, 28 insertions, 10 deletions

diff --git a/ChangeLog b/ChangeLog
index 85b17c1f..4728310a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,6 +7,17 @@
 
 	* tl.vim, txr.vim: Regenerated.
 
+2014-12-25  Kaz Kylheku  <kaz@kylheku.com>
+
+	* lib.c (simple_lazy_stream_func): Bugfix: close the stream
+	if get_line returns nil.
+
+	* stream.c (cat_get_line, cat_get_char, cat_get_byte): The catenated
+	stream read operations close an exhausted stream before popping
+	to the next one.
+
+	* txr.1: Document closing behavior of catenated streams.
+
 2014-12-23  Kaz Kylheku  <kaz@kylheku.com>
 
 	* eval.c (ap_s, ret_s, aret_s): New symbol variables.
diff --git a/lib.c b/lib.c
index 11cf2f83..dd038866 100644
--- a/lib.c
+++ b/lib.c
@@ -5083,10 +5083,12 @@ toobig:
 
 static val simple_lazy_stream_func(val stream, val lcons)
 {
-  if (set(mkloc(lcons->lc.car, lcons), get_line(stream)) != nil)
+  if (set(mkloc(lcons->lc.car, lcons), get_line(stream)) != nil) {
     set(mkloc(lcons->lc.cdr, lcons), make_lazy_cons(lcons->lc.func));
-  else
+  } else {
+    close_stream(stream, t);
     lcons->lc.cdr = nil;
+  }
 
   return nil;
 }
diff --git a/stream.c b/stream.c
index c4632344..7945e43c 100644
--- a/stream.c
+++ b/stream.c
@@ -2386,9 +2386,11 @@ static val cat_get_line(val stream)
   val streams = coerce(val, stream->co.handle);
 
   while (streams) {
-    val line = get_line(first(streams));
+    val fs = first(streams);
+    val line = get_line(fs);
     if (line)
       return line;
+    close_stream(fs, t);
     if ((streams = rest(streams)) != nil)
       stream->co.handle = coerce(mem_t *, streams);
   }
@@ -2401,9 +2403,11 @@ static val cat_get_char(val stream)
   val streams = coerce(val, stream->co.handle);
 
   while (streams) {
-    val ch = get_char(first(streams));
+    val fs = first(streams);
+    val ch = get_char(fs);
     if (ch)
       return ch;
+    close_stream(fs, t);
     if ((streams = rest(streams)) != nil)
       stream->co.handle = coerce(mem_t *, streams);
   }
@@ -2416,9 +2420,11 @@ static val cat_get_byte(val stream)
   val streams = coerce(val, stream->co.handle);
 
   while (streams) {
-    val byte = get_byte(first(streams));
+    val fs = first(streams);
+    val byte = get_byte(fs);
     if (byte)
       return byte;
+    close_stream(fs, t);
     if ((streams = rest(streams)) != nil)
       stream->co.handle = coerce(mem_t *, streams);
   }
diff --git a/txr.1 b/txr.1
index 318dc5ae..af4e55fe 100644
--- a/txr.1
+++ b/txr.1
@@ -22342,11 +22342,10 @@ or
 .code get-line
 operation on the head stream yields
 .codn nil ,
-and there are more lists in the stream, then the stream is removed from the
-list, and the next stream, if any, becomes the head list. The operation is then
-tried again.  If any of these operations fail on the last list, it is not
-removed from the list, so that a stream remains in place which can take
-the
+and there are more lists in the stream, then the stream is closed, removed from
+the list, and the next stream, if any, becomes the head list. The operation is
+then tried again.  If any of these operations fail on the last list, it is not
+removed from the list, so that a stream remains in place which can take the
 .code unget-char
 or
 .code unget-byte