diff options
Diffstat (limited to 'stream.c')
| -rw-r--r-- | stream.c | 43 |
1 files changed, 38 insertions, 5 deletions
@@ -2253,7 +2253,8 @@ static val cat_get_line(val stream) val line = get_line(first(streams)); if (line) return line; - stream->co.handle = (mem_t *) (streams = rest(streams)); + if ((streams = rest(streams)) != nil) + stream->co.handle = (mem_t *) streams; } return nil; @@ -2267,7 +2268,8 @@ static val cat_get_char(val stream) val ch = get_char(first(streams)); if (ch) return ch; - stream->co.handle = (mem_t *) (streams = rest(streams)); + if ((streams = rest(streams)) != nil) + stream->co.handle = (mem_t *) streams; } return nil; @@ -2281,12 +2283,43 @@ static val cat_get_byte(val stream) val byte = get_byte(first(streams)); if (byte) return byte; - stream->co.handle = (mem_t *) (streams = rest(streams)); + if ((streams = rest(streams)) != nil) + stream->co.handle = (mem_t *) streams; } return nil; } +static val cat_unget_byte(val stream, int byte) +{ + val streams = (val) stream->co.handle; + + if (!streams) { + uw_throwf(file_error_s, + lit("unget-byte on catenated stream ~a: stream list empty"), + stream, nao); + } else { + val stream = car(streams); + return unget_byte(stream, num_fast(byte)); + } + + return nil; +} + +static val cat_unget_char(val stream, val ch) +{ + val streams = (val) stream->co.handle; + + if (!streams) { + uw_throwf(file_error_s, + lit("unget-char on catenated stream ~a: stream list empty"), + stream, nao); + } else { + val stream = car(streams); + return unget_char(stream, ch); + } +} + static val cat_get_prop(val stream, val ind) { val streams = (val) stream->co.handle; @@ -2307,8 +2340,8 @@ static struct strm_ops cat_stream_ops = { cat_get_line, cat_get_char, cat_get_byte, - 0, /* unget_char, */ - 0, /* unget_byte, */ + cat_unget_char, + cat_unget_byte, 0, /* close, */ 0, /* flush, */ 0, /* seek, */ |