diff options
Diffstat (limited to 'sys/base/bufio/unget.c')
-rw-r--r-- | sys/base/bufio/unget.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/sys/base/bufio/unget.c b/sys/base/bufio/unget.c new file mode 100644 index 0000000..3fd16de --- /dev/null +++ b/sys/base/bufio/unget.c @@ -0,0 +1,18 @@ +#include "internal.h" + +error +bufio·ungetbyte(io·Buffer *buf, byte c) +{ + if(!(buf->state & bufio·rdr)) { + errorf("attempted to unget on non-active reader"); + return bufio·err; + } + + if(buf->pos == buf->buf) { + errorf("attempted to unget past end of buffer"); + return bufio·err; + } + + buf->pos--; + return 0; +} |