# New Ticket Created by Cory Spencer
# Please include the string: [perl #25265]
# in the subject line of all future correspondence about this issue.
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=25265 >
'peek' implements an opcode which can look ahead at an arbitrary number of
bytes in a IO stream, but does not remove the bytes from the stream in the
process.
The proposed format is:
peek(out STR, in INT)
where $1 contains up to $2 peek'ed bytes from STDIN, and
peek(out STR, in PMC, in INT)
where $1 contains up to $2 peek'ed bytes from $3
This patch touches the following file:
include/parrot/io.h
io/io.c
io/io_buf.c
io/io_passdown.c
io/io_private.h
If the patch is located in the base parrot directory, it can be applied
as:
~$ patch -p1 < peek-opcode.patch
Only in parrot-2/: CFLAGS
Only in parrot-2/: Makefile
Only in parrot-2/classes: Makefile
Only in parrot-2/docs: Makefile
Only in parrot-2/dynclasses: Makefile
Only in parrot-2/dynoplibs: Makefile
Only in parrot-2/imcc: Makefile
Only in parrot-2/include/parrot: charclass.h
Only in parrot-2/include/parrot: config.h
Only in parrot-2/include/parrot: core_pmcs.h
Only in parrot-2/include/parrot: exec_dep.h
Only in parrot-2/include/parrot: feature.h
Only in parrot-2/include/parrot: has_header.h
diff -ru parrot-1/include/parrot/io.h parrot-2/include/parrot/io.h
--- parrot-1/include/parrot/io.h 2003-11-19 05:29:35.000000000 -0800
+++ parrot-2/include/parrot/io.h 2004-01-25 09:50:41.000000000 -0800
@@ -190,6 +190,8 @@
DummyCodeRef *);
INTVAL (*Flush)(theINTERP, ParrotIOLayer * layer,
ParrotIO * io);
+ size_t (*Peek)(theINTERP, ParrotIOLayer * layer,
+ ParrotIO * io, void * buf, size_t len);
PIOOFF_T (*Seek)(theINTERP, ParrotIOLayer * layer,
ParrotIO * io, PIOOFF_T offset, INTVAL whence);
PIOOFF_T (*Tell)(theINTERP, ParrotIOLayer * layer,
@@ -269,6 +271,7 @@
extern INTVAL PIO_setbuf(theINTERP, PMC *, size_t);
extern INTVAL PIO_setlinebuf(theINTERP, PMC *);
extern INTVAL PIO_puts(theINTERP, PMC *, const char *);
+extern INTVAL PIO_peek(theINTERP, PMC *, void *, size_t);
extern PIOOFF_T PIO_seek(theINTERP, PMC *, PIOOFF_T offset, INTVAL whence);
extern INTVAL PIO_eof(theINTERP, PMC *);
extern INTVAL PIO_pioctl(theINTERP, PMC *, INTVAL cmd, INTVAL arg);
Only in parrot-2/include/parrot: platform.h
Only in parrot-2/include/parrot: platform_interface.h
diff -ru parrot-1/io/io.c parrot-2/io/io.c
--- parrot-1/io/io.c 2004-01-25 08:32:51.000000000 -0800
+++ parrot-2/io/io.c 2004-01-25 09:46:49.000000000 -0800
@@ -670,6 +670,21 @@
/*
+ * Iterate down the stack to the first layer implementing "Peek" API
+ */
+INTVAL
+PIO_peek(theINTERP, PMC *pmc, void *buffer, size_t len)
+{
+ ParrotIOLayer *l = pmc->cache.struct_val;
+ ParrotIO *io = PMC_data(pmc);
+ if(!io)
+ return -1;
+
+ return PIO_peek_down(interpreter, l, io, buffer, len);
+}
+
+
+/*
* Iterate down the stack to the first layer implementing "Seek" API
*/
PIOOFF_T
diff -ru parrot-1/io/io_buf.c parrot-2/io/io_buf.c
--- parrot-1/io/io_buf.c 2004-01-25 08:32:51.000000000 -0800
+++ parrot-2/io/io_buf.c 2004-01-25 09:48:03.000000000 -0800
@@ -46,6 +46,8 @@
ParrotIO *io, void *buffer, size_t len);
static size_t PIO_buf_write(theINTERP, ParrotIOLayer *l,
ParrotIO *io, const void *buffer, size_t len);
+static size_t PIO_buf_peek(theINTERP, ParrotIOLayer *l,
+ ParrotIO *io, void *buffer, size_t len);
static PIOOFF_T PIO_buf_seek(theINTERP, ParrotIOLayer *l, ParrotIO *io,
PIOOFF_T offset, INTVAL whence);
static PIOOFF_T PIO_buf_tell(theINTERP, ParrotIOLayer *l, ParrotIO *io);
@@ -357,6 +359,55 @@
static size_t
+PIO_buf_peek(theINTERP, ParrotIOLayer *layer, ParrotIO *io,
+ void *buffer, size_t len)
+{
+ ParrotIOLayer *l = layer;
+ ParrotIOBuf *b;
+ unsigned char *out_buf = buffer;
+ size_t current = 0;
+
+ /* write buffer flush */
+ if (io->b.flags & PIO_BF_WRITEBUF) {
+ PIO_buf_flush(interpreter, layer, io);
+ }
+
+ b = &io->b;
+
+ /* read Data from buffer */
+ if (b->flags & PIO_BF_READBUF) {
+ size_t avail = b->endb - b->next;
+
+ current = avail < len ? avail : len;
+ memcpy(out_buf, b->next, current);
+
+ if (len == current) {
+ return current;
+ }
+ else {
+ /* more data needed from downlayer */
+ out_buf += current;
+ len -= current;
+ }
+ }
+
+ /* (re)fill the readbuffer */
+ if (!(b->flags & PIO_BF_READBUF)) {
+ size_t got;
+
+ got = PIO_buf_fill_readbuf(interpreter, l, io, b);
+
+ len = len < got ? len : got;
+ }
+
+ /* read from the read_buffer */
+ memcpy(out_buf, io->b.next, len);
+
+ return current + len;
+}
+
+
+static size_t
PIO_buf_readline(theINTERP, ParrotIOLayer *layer, ParrotIO *io,
void *buffer, size_t len)
{
@@ -533,6 +584,7 @@
PIO_buf_read,
PIO_null_read_async,
PIO_buf_flush,
+ PIO_buf_peek,
PIO_buf_seek,
PIO_buf_tell,
PIO_buf_setbuf,
diff -ru parrot-1/io/io_passdown.c parrot-2/io/io_passdown.c
--- parrot-1/io/io_passdown.c 2003-10-11 06:15:30.000000000 -0700
+++ parrot-2/io/io_passdown.c 2004-01-25 09:55:07.000000000 -0800
@@ -143,6 +143,19 @@
return 0;
}
+size_t
+PIO_peek_down(theINTERP, ParrotIOLayer * layer, ParrotIO * io, void * buf,
+ size_t len)
+{
+ while (layer) {
+ if (layer->api->Peek) {
+ return layer->api->Peek(interpreter, layer, io, buf, len);
+ }
+ layer = PIO_DOWNLAYER(layer);
+ }
+ /* No layer found */
+ return 0;
+}
INTVAL
PIO_flush_down(theINTERP, ParrotIOLayer * layer, ParrotIO * io)
diff -ru parrot-1/io/io_private.h parrot-2/io/io_private.h
--- parrot-1/io/io_private.h 2003-10-11 06:15:30.000000000 -0700
+++ parrot-2/io/io_private.h 2004-01-25 09:45:58.000000000 -0800
@@ -122,6 +122,8 @@
size_t PIO_read_async_down(theINTERP, ParrotIOLayer * layer, ParrotIO * io,
void * buf, size_t len, DummyCodeRef *);
INTVAL PIO_flush_down(theINTERP, ParrotIOLayer * layer, ParrotIO * io);
+size_t PIO_peek_down(theINTERP, ParrotIOLayer * layer, ParrotIO * io,
+ void * buf, size_t len);
PIOOFF_T PIO_seek_down(theINTERP, ParrotIOLayer * layer, ParrotIO * io,
PIOOFF_T offset, INTVAL whence);
PIOOFF_T PIO_tell_down(theINTERP, ParrotIOLayer * layer, ParrotIO * io);
Only in parrot-2/languages: Makefile
Only in parrot-2/languages/befunge: Makefile
Only in parrot-2/languages/bf: Makefile
Only in parrot-2/languages/jako: Makefile
Only in parrot-2/languages/m4: Makefile
Only in parrot-2/languages/miniperl: Makefile
Only in parrot-2/languages/ook: Makefile
Only in parrot-2/languages/perl6: Makefile
Only in parrot-2/languages/scheme: Makefile
Only in parrot-2/languages/tcl: Makefile
Only in parrot-2/languages/urm: Makefile
Only in parrot-2/lib/Parrot: Config.pm
Only in parrot-2/lib/Parrot: PMC.pm
Only in parrot-2/: libparrot.def
Only in parrot-2/: myconfig
Only in parrot-2/ops: core_ops.c
Only in parrot-2/ops: core_ops_prederef.c
Only in parrot-2/ops: core_ops_switch.c
diff -ru parrot-1/ops/io.ops parrot-2/ops/io.ops
--- parrot-1/ops/io.ops 2003-11-07 04:12:33.000000000 -0800
+++ parrot-2/ops/io.ops 2004-01-25 09:44:55.000000000 -0800
@@ -404,6 +404,55 @@
##########################################
+=item B<peek>(out STR, in INT)
+
+Reads up to N bytes from standard input, but does not
+remove them from the stream.
+
+=item B<peek>(out STR, in PMC, in INT)
+
+Reads up to N bytes from an IO PMC, but does not
+remove them from the stream.
+
+=cut
+
+op peek(out STR, in INT) {
+ UINTVAL n;
+ INTVAL nr;
+ if($2 >= 65535)
+ n = 65535;
+ else
+ n = $2;
+ $1 = string_make(interpreter, NULL, n, NULL, 0, NULL);
+ memset(($1)->strstart, 0, n);
+ nr = PIO_peek(interpreter, PIO_STDIN(interpreter),
+ ($1)->strstart, (size_t)n);
+ if(nr > 0)
+ ($1)->strlen = ($1)->bufused = nr;
+ else
+ ($1)->strlen = ($1)->bufused = 0;
+ goto NEXT();
+}
+
+op peek(out STR, in PMC, in INT) {
+ UINTVAL n;
+ INTVAL nr;
+ if($3 >= 65535)
+ n = 65535;
+ else
+ n = $3;
+ $1 = string_make(interpreter, NULL, n, NULL, 0, NULL);
+ memset(($1)->strstart, 0, n);
+ nr = PIO_peek(interpreter, $2, ($1)->strstart, (size_t)n);
+ if(nr > 0)
+ ($1)->strlen = ($1)->bufused = nr;
+ else
+ ($1)->strlen = ($1)->bufused = 0;
+ goto NEXT();
+}
+
+##########################################
+
=item B<seek>(in PMC, in INT, in INT)
seek:
Only in parrot-2/runtime/parrot/include: chartypes.pasm
Only in parrot-2/runtime/parrot/include: datatypes.pasm
Only in parrot-2/runtime/parrot/include: encodings.pasm
Only in parrot-2/runtime/parrot/include: except_severity.pasm
Only in parrot-2/runtime/parrot/include: except_types.pasm
Only in parrot-2/runtime/parrot/include: iglobals.pasm
Only in parrot-2/runtime/parrot/include: interpcores.pasm
Only in parrot-2/runtime/parrot/include: interpflags.pasm
Only in parrot-2/runtime/parrot/include: interpinfo.pasm
Only in parrot-2/runtime/parrot/include: iotypes.pasm
Only in parrot-2/runtime/parrot/include: iterator.pasm
Only in parrot-2/runtime/parrot/include: longopt.pasm
Only in parrot-2/runtime/parrot/include: pmctypes.pasm
Only in parrot-2/runtime/parrot/include: signal.pasm
Only in parrot-2/runtime/parrot/include: stdio.pasm
Only in parrot-2/runtime/parrot/include: stringinfo.pasm
Only in parrot-2/runtime/parrot/include: sysinfo.pasm
Only in parrot-2/runtime/parrot/include: timer.pasm
Only in parrot-2/runtime/parrot/include: vtable_methods.pasm
Only in parrot-2/runtime/parrot/include: warnings.pasm
Only in parrot-2/src: core_pmcs.c
Only in parrot-2/src: platform.c
