-/* Copyright (C) 1995,1996,1998,1999,2000,2001,2002, 2003 Free Software Foundation, Inc.
- *
+/* Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2005, 2006,
+ * 2009, 2010, 2011, 2012, 2014 Free Software Foundation, Inc.
+ *
* This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 3 of
+ * the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA
*/
\f
-#if HAVE_CONFIG_H
+#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "libguile/_scm.h"
#include <stdio.h>
-#ifdef HAVE_UNISTD_H
#include <unistd.h>
-#endif
-#include "libguile/unif.h"
+#include "libguile/bytevectors.h"
#include "libguile/eval.h"
#include "libguile/ports.h"
#include "libguile/read.h"
#include "libguile/modules.h"
#include "libguile/validate.h"
#include "libguile/deprecation.h"
+#include "libguile/srfi-4.h"
#include "libguile/strports.h"
/* NOTES:
- We break the rules set forth by strings.h about accessing the
- internals of strings here. We can do this since we can guarantee
- that the string used as pt->stream is not in use by anyone else.
- Thus, it's representation will not change asynchronously.
-
- (Ports aren't thread-safe yet anyway...)
-
- write_buf/write_end point to the ends of the allocated string.
- read_buf/read_end in principle point to the part of the string which
+ write_buf/write_end point to the ends of the allocated bytevector.
+ read_buf/read_end in principle point to the part of the bytevector which
has been written to, but this is only updated after a flush.
read_pos and write_pos in principle should be equal, but this is only true
when rw_active is SCM_PORT_NEITHER.
-*/
+
+ ENHANCE-ME - output blocks:
+
+ The current code keeps an output string as a single block. That means
+ when the size is increased the entire old contents must be copied. It'd
+ be more efficient to begin a new block when the old one is full, so
+ there's no re-copying of previous data.
+
+ To make seeking efficient, keeping the pieces in a vector might be best,
+ though appending is probably the most common operation. The size of each
+ block could be progressively increased, so the bigger the string the
+ bigger the blocks.
+
+ When `get-output-string' is called the blocks have to be coalesced into a
+ string, the result could be kept as a single big block. If blocks were
+ strings then `get-output-string' could notice when there's just one and
+ return that with a copy-on-write (though repeated calls to
+ `get-output-string' are probably unlikely).
+
+ Another possibility would be to extend the port mechanism to let SCM
+ strings come through directly from `display' and friends. That way if a
+ big string is written it can be kept as a copy-on-write, saving time
+ copying and maybe saving some space. */
+
scm_t_bits scm_tc16_strport;
return scm_return_first_int (*pt->read_pos, port);
}
-/* change the size of a port's string to new_size. this doesn't
- change read_buf_size. */
-static void
-st_resize_port (scm_t_port *pt, off_t new_size)
+/* Change the size of a port's bytevector to NEW_SIZE. This doesn't
+ change `read_buf_size'. */
+static void
+st_resize_port (scm_t_port *pt, scm_t_off new_size)
{
SCM old_stream = SCM_PACK (pt->stream);
- const char *src = scm_i_string_chars (old_stream);
- char *dst;
- SCM new_stream = scm_i_make_string (new_size, &dst);
- unsigned long int old_size = scm_i_string_length (old_stream);
+ const signed char *src = SCM_BYTEVECTOR_CONTENTS (old_stream);
+ SCM new_stream = scm_c_make_bytevector (new_size);
+ signed char *dst = SCM_BYTEVECTOR_CONTENTS (new_stream);
+ unsigned long int old_size = SCM_BYTEVECTOR_LENGTH (old_stream);
unsigned long int min_size = min (old_size, new_size);
- unsigned long int i;
- off_t index = pt->write_pos - pt->write_buf;
+ scm_t_off index = pt->write_pos - pt->write_buf;
pt->write_buf_size = new_size;
- for (i = 0; i != min_size; ++i)
- dst[i] = src[i];
+ memcpy (dst, src, min_size);
scm_remember_upto_here_1 (old_stream);
}
}
-/* amount by which write_buf is expanded. */
-#define SCM_WRITE_BLOCK 80
-
-/* ensure that write_pos < write_end by enlarging the buffer when
- necessary. update read_buf to account for written chars. */
+/* Ensure that `write_pos' < `write_end' by enlarging the buffer when
+ necessary. Update `read_buf' to account for written chars. The
+ buffer is enlarged geometrically. */
static void
st_flush (SCM port)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
if (pt->write_pos == pt->write_end)
- {
- st_resize_port (pt, pt->write_buf_size + SCM_WRITE_BLOCK);
- }
+ st_resize_port (pt, pt->write_buf_size * 2);
+
pt->read_pos = pt->write_pos;
if (pt->read_pos > pt->read_end)
{
pt->rw_active = SCM_PORT_NEITHER;
}
-static off_t
-st_seek (SCM port, off_t offset, int whence)
+static scm_t_off
+st_seek (SCM port, scm_t_off offset, int whence)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
- off_t target;
+ scm_t_off target;
if (pt->rw_active == SCM_PORT_READ && offset == 0 && whence == SEEK_CUR)
/* special case to avoid disturbing the unread-char buffer. */
SCM_EOL);
}
}
- else
- {
- st_resize_port (pt, target + (target == pt->write_buf_size
- ? SCM_WRITE_BLOCK
- : 0));
- }
+ else if (target == pt->write_buf_size)
+ st_resize_port (pt, target * 2);
}
pt->read_pos = pt->write_pos = pt->read_buf + target;
if (pt->read_pos > pt->read_end)
}
static void
-st_truncate (SCM port, off_t length)
+st_truncate (SCM port, scm_t_off length)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
pt->write_pos = pt->read_end;
}
-SCM
+/* The initial size in bytes of a string port's buffer. */
+#define INITIAL_BUFFER_SIZE 128
+
+/* Return a new string port with MODES. If STR is #f, a new backing
+ buffer is allocated; otherwise STR must be a string and a copy of it
+ serves as the buffer for the new port. */
+SCM
scm_mkstrport (SCM pos, SCM str, long modes, const char *caller)
{
- SCM z;
+ SCM z, buf;
scm_t_port *pt;
size_t str_len, c_pos;
-
- SCM_ASSERT (scm_is_string (str), str, SCM_ARG1, caller);
-
- str_len = scm_i_string_length (str);
- c_pos = scm_to_unsigned_integer (pos, 0, str_len);
+ char *c_buf;
if (!((modes & SCM_WRTNG) || (modes & SCM_RDNG)))
scm_misc_error ("scm_mkstrport", "port must read or write", SCM_EOL);
- /* XXX
-
- Make a new string to isolate us from changes to the original.
- This is done so that we can rely on scm_i_string_chars to stay in
- place even across SCM_TICKs.
+ scm_dynwind_begin (0);
+ scm_i_dynwind_pthread_mutex_lock (&scm_i_port_table_mutex);
- Additionally, when we are going to write to the string, we make a
- copy so that we can write to it without having to use
- scm_i_string_writable_chars.
- */
+ z = scm_new_port_table_entry (scm_tc16_strport);
+ SCM_SET_CELL_TYPE (z, scm_tc16_strport);
+ pt = SCM_PTAB_ENTRY (z);
- if (modes & SCM_WRTNG)
- str = scm_c_substring_copy (str, 0, str_len);
+ /* Make PT initially empty, and release the port-table mutex
+ immediately. This is so that if one of the function calls below
+ raises an exception, a pre-unwind catch handler can still create
+ new ports; for instance, `display-backtrace' needs to be able to
+ allocate a new string port. See <http://bugs.gnu.org/11197>. */
+ scm_port_non_buffer (pt);
+ SCM_SETSTREAM (z, SCM_UNPACK (scm_null_bytevector));
+
+ scm_dynwind_end ();
+
+ if (scm_is_false (str))
+ {
+ /* Allocate a new buffer to write to. */
+ str_len = INITIAL_BUFFER_SIZE;
+ buf = scm_c_make_bytevector (str_len);
+ c_buf = (char *) SCM_BYTEVECTOR_CONTENTS (buf);
+ c_pos = 0;
+ }
else
- str = scm_c_substring (str, 0, str_len);
+ {
+ /* STR is a string. */
+ char *copy;
- scm_i_scm_pthread_mutex_lock (&scm_i_port_table_mutex);
- z = scm_new_port_table_entry (scm_tc16_strport);
- pt = SCM_PTAB_ENTRY(z);
- SCM_SETSTREAM (z, SCM_UNPACK (str));
- SCM_SET_CELL_TYPE(z, scm_tc16_strport|modes);
- /* see above why we can use scm_i_string_chars here. */
- pt->write_buf = pt->read_buf = (unsigned char *) scm_i_string_chars (str);
+ SCM_ASSERT (scm_is_string (str), str, SCM_ARG1, caller);
+
+ /* Create a copy of STR in the encoding of PT. */
+ copy = scm_to_stringn (str, &str_len, pt->encoding,
+ SCM_FAILED_CONVERSION_ERROR);
+ buf = scm_c_make_bytevector (str_len);
+ c_buf = (char *) SCM_BYTEVECTOR_CONTENTS (buf);
+ memcpy (c_buf, copy, str_len);
+ free (copy);
+
+ c_pos = scm_to_unsigned_integer (pos, 0, str_len);
+ }
+
+ /* Now, finish up the port. */
+ scm_i_pthread_mutex_lock (&scm_i_port_table_mutex);
+
+ SCM_SETSTREAM (z, SCM_UNPACK (buf));
+ SCM_SET_CELL_TYPE (z, scm_tc16_strport | modes);
+
+ if (scm_is_false (str))
+ /* Reset `read_buf_size'. It will contain the actual number of
+ bytes written to PT. */
+ pt->read_buf_size = 0;
+ else
+ pt->read_buf_size = str_len;
+
+ pt->write_buf = pt->read_buf = (unsigned char *) c_buf;
pt->read_pos = pt->write_pos = pt->read_buf + c_pos;
- pt->write_buf_size = pt->read_buf_size = str_len;
+ pt->write_buf_size = str_len;
pt->write_end = pt->read_end = pt->read_buf + pt->read_buf_size;
pt->rw_random = 1;
scm_i_pthread_mutex_unlock (&scm_i_port_table_mutex);
- /* ensure write_pos is writable. */
+ /* Ensure WRITE_POS is writable. */
if ((modes & SCM_WRTNG) && pt->write_pos == pt->write_end)
st_flush (z);
+
return z;
}
-/* create a new string from a string port's buffer. */
-SCM scm_strport_to_string (SCM port)
+/* Create a new string from the buffer of PORT, a string port, converting from
+ PORT's encoding to the standard string representation. */
+SCM
+scm_strport_to_string (SCM port)
{
- scm_t_port *pt = SCM_PTAB_ENTRY (port);
SCM str;
- char *dst;
-
+ scm_t_port *pt = SCM_PTAB_ENTRY (port);
+
if (pt->rw_active == SCM_PORT_WRITE)
st_flush (port);
- str = scm_i_make_string (pt->read_buf_size, &dst);
- memcpy (dst, (char *) pt->read_buf, pt->read_buf_size);
+ if (pt->read_buf_size == 0)
+ return scm_nullstr;
+
+ if (pt->encoding == NULL)
+ {
+ char *buf;
+ str = scm_i_make_string (pt->read_buf_size, &buf, 0);
+ memcpy (buf, pt->read_buf, pt->read_buf_size);
+ }
+ else
+ str = scm_from_stringn ((char *)pt->read_buf, pt->read_buf_size,
+ pt->encoding, pt->ilseq_handler);
scm_remember_upto_here_1 (port);
return str;
}
"argument @var{printer} (default: @code{write}).")
#define FUNC_NAME s_scm_object_to_string
{
- SCM str, port;
+ SCM port, result;
if (!SCM_UNBNDP (printer))
SCM_VALIDATE_PROC (2, printer);
- str = scm_c_make_string (0, SCM_UNDEFINED);
- port = scm_mkstrport (SCM_INUM0, str, SCM_OPN | SCM_WRTNG, FUNC_NAME);
+ port = scm_mkstrport (SCM_INUM0, SCM_BOOL_F,
+ SCM_OPN | SCM_WRTNG, FUNC_NAME);
if (SCM_UNBNDP (printer))
scm_write (obj, port);
else
scm_call_2 (printer, obj, port);
- return scm_strport_to_string (port);
+ result = scm_strport_to_string (port);
+
+ /* Explicitly close PORT so that the iconv CDs associated with it are
+ deallocated right away. This is important because CDs use a lot of
+ memory that's not visible to the GC, so not freeing them can lead
+ to almost large heap usage. See
+ <http://wingolog.org/archives/2011/02/25/ports-weaks-gc-and-dark-matter>
+ for details. */
+ scm_close_port (port);
+
+ return result;
}
#undef FUNC_NAME
{
SCM p;
- p = scm_mkstrport (SCM_INUM0,
- scm_make_string (SCM_INUM0, SCM_UNDEFINED),
+ p = scm_mkstrport (SCM_INUM0, SCM_BOOL_F,
SCM_OPN | SCM_WRTNG,
FUNC_NAME);
scm_call_1 (proc, p);
{
SCM p;
- p = scm_mkstrport (SCM_INUM0,
- scm_make_string (SCM_INUM0, SCM_UNDEFINED),
+ p = scm_mkstrport (SCM_INUM0, SCM_BOOL_F,
SCM_OPN | SCM_WRTNG,
FUNC_NAME);
return p;
"scm_c_read_string");
SCM form;
- /* Read expressions from that port; ignore the values. */
form = scm_read (port);
scm_close_port (port);
}
-static SCM
-inner_eval_string (void *data)
-{
- SCM port = (SCM)data;
- SCM form;
- SCM ans = SCM_UNSPECIFIED;
-
- /* Read expressions from that port; ignore the values. */
- while (!SCM_EOF_OBJECT_P (form = scm_read (port)))
- ans = scm_primitive_eval_x (form);
+static SCM eval_string_var;
+static SCM k_module;
- /* Don't close the port here; if we re-enter this function via a
- continuation, then the next time we enter it, we'll get an error.
- It's a string port anyway, so there's no advantage to closing it
- early. */
-
- return ans;
+static void
+init_eval_string_var_and_k_module (void)
+{
+ eval_string_var = scm_c_public_variable ("ice-9 eval-string", "eval-string");
+ k_module = scm_from_locale_keyword ("module");
}
SCM_DEFINE (scm_eval_string_in_module, "eval-string", 1, 1, 0,
"procedure returns.")
#define FUNC_NAME s_scm_eval_string_in_module
{
- SCM port = scm_mkstrport (SCM_INUM0, string, SCM_OPN | SCM_RDNG,
- FUNC_NAME);
+ static scm_i_pthread_once_t once = SCM_I_PTHREAD_ONCE_INIT;
+ scm_i_pthread_once (&once, init_eval_string_var_and_k_module);
+
if (SCM_UNBNDP (module))
module = scm_current_module ();
else
SCM_VALIDATE_MODULE (2, module);
- return scm_c_call_with_current_module (module,
- inner_eval_string, (void *)port);
+
+ return scm_call_3 (scm_variable_ref (eval_string_var),
+ string, k_module, module);
}
#undef FUNC_NAME
{
scm_t_bits tc = scm_make_port_type ("string", stfill_buffer, st_write);
- scm_set_port_mark (tc, scm_markstream);
scm_set_port_end_input (tc, st_end_input);
scm_set_port_flush (tc, st_flush);
scm_set_port_seek (tc, st_seek);
HCoop / bpt / guile.git / blobdiff