[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered por
From: |
Andy Wingo |
Subject: |
bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports |
Date: |
Wed, 10 Jan 2018 17:32:04 +0100 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/25.3 (gnu/linux) |
On Wed 10 Jan 2018 16:59, address@hidden (Ludovic Courtès) writes:
> address@hidden (Ludovic Courtès) skribis:
>
>> As discussed on IRC, ‘get-bytevector-some’ returns only 1 byte from
>> unbuffered ports:
>
> Here’s a tentative fix. WDYT?
Thanks! Needs a little work though :) Comments inline.
> --- a/libguile/ports.h
> +++ b/libguile/ports.h
> @@ -69,6 +69,7 @@ SCM_INTERNAL SCM scm_i_port_weak_set;
> #define SCM_OPOUTPORTP(x) (SCM_OPPORTP (x) && SCM_OUTPUT_PORT_P (x))
> #define SCM_OPENP(x) (SCM_OPPORTP (x))
> #define SCM_CLOSEDP(x) (!SCM_OPENP (x))
> +#define SCM_UNBUFFEREDP(x) (SCM_PORTP (x) && (SCM_CELL_WORD_0 (x) &
> SCM_BUF0))
> #define SCM_CLR_PORT_OPEN_FLAG(p) \
> SCM_SET_CELL_WORD_0 ((p), SCM_CELL_WORD_0 (p) & ~SCM_OPN)
> #ifdef BUILDING_LIBGUILE
Please guard this under #ifdef BUILDING_LIBGUILE.
> @@ -487,16 +487,33 @@ SCM_DEFINE (scm_get_bytevector_some,
> "get-bytevector-some", 1, 0, 0,
>
> SCM_VALIDATE_BINARY_INPUT_PORT (1, port);
>
> - buf = scm_fill_input (port, 0, &cur, &avail);
> - if (avail == 0)
> + if (SCM_UNBUFFEREDP (port))
> {
> - scm_port_buffer_set_has_eof_p (buf, SCM_BOOL_F);
> - return SCM_EOF_VAL;
> + size_t read;
> +
> + bv = scm_c_make_bytevector (4096);
> + read = scm_i_read_bytes (port, bv, 0, SCM_BYTEVECTOR_LENGTH (bv));
> +
> + if (read == 0)
> + return SCM_EOF_VAL;
> + else if (read < SCM_BYTEVECTOR_LENGTH (bv))
> + return scm_c_shrink_bytevector (bv, read);
> + else
> + return bv;
> }
> + else
> + {
> + buf = scm_fill_input (port, 0, &cur, &avail);
> + if (avail == 0)
> + {
> + scm_port_buffer_set_has_eof_p (buf, SCM_BOOL_F);
> + return SCM_EOF_VAL;
> + }
>
> - bv = scm_c_make_bytevector (avail);
> - scm_port_buffer_take (buf, (scm_t_uint8 *) SCM_BYTEVECTOR_CONTENTS (bv),
> - avail, cur, avail);
> + bv = scm_c_make_bytevector (avail);
> + scm_port_buffer_take (buf, (scm_t_uint8 *) SCM_BYTEVECTOR_CONTENTS
> (bv),
> + avail, cur, avail);
> + }
>
> return bv;
> }
There are tabs in your code; would you mind doing only spaces?
A port being unbuffered doesn't mean that it has no bytes in its
buffer. In particular, scm_unget_bytes may put bytes back into the
buffer. Or, peek-u8 might fill this buffer with one byte.
Also, they port may have buffered write bytes (could be the port has
write buffering but no read buffering). In that case (pt->rw_random)
you need to scm_flush().
I suggest taking the buffered bytes from the read buffer, if any. Then
if the port is unbuffered, make a bytevector and call scm_i_read_bytes;
otherwise do the scm_fill_input path that's there already.
One more thing, if the port goes EOF, you need to
scm_port_buffer_set_has_eof_p.
Regards,
Andy
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Ludovic Courtès, 2018/01/10
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Ludovic Courtès, 2018/01/10
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports,
Andy Wingo <=
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Ludovic Courtès, 2018/01/11
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Mark H Weaver, 2018/01/11
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Ludovic Courtès, 2018/01/11
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Mark H Weaver, 2018/01/11
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Andy Wingo, 2018/01/12
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Ludovic Courtès, 2018/01/12
- bug#30066: 'get-bytevector-some' returns only 1 byte from unbuffered ports, Andy Wingo, 2018/01/12