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/* Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2006,
* 2011 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 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
* 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., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "libguile/_scm.h"
#include <stdio.h>
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include "libguile/chars.h"
#include "libguile/modules.h"
#include "libguile/ports.h"
#include "libguile/rdelim.h"
#include "libguile/strings.h"
#include "libguile/strports.h"
#include "libguile/validate.h"
SCM_DEFINE (scm_read_delimited_x, "%read-delimited!", 3, 3, 0,
(SCM delims, SCM str, SCM gobble, SCM port, SCM start, SCM end),
"Read characters from @var{port} into @var{str} until one of the\n"
"characters in the @var{delims} string is encountered. If\n"
"@var{gobble} is true, discard the delimiter character;\n"
"otherwise, leave it in the input stream for the next read. If\n"
"@var{port} is not specified, use the value of\n"
"@code{(current-input-port)}. If @var{start} or @var{end} are\n"
"specified, store data only into the substring of @var{str}\n"
"bounded by @var{start} and @var{end} (which default to the\n"
"beginning and end of the string, respectively).\n"
"\n"
" Return a pair consisting of the delimiter that terminated the\n"
"string and the number of characters read. If reading stopped\n"
"at the end of file, the delimiter returned is the\n"
"@var{eof-object}; if the string was filled without encountering\n"
"a delimiter, this value is @code{#f}.")
#define FUNC_NAME s_scm_read_delimited_x
{
size_t j;
size_t cstart;
size_t cend;
scm_t_wchar c;
size_t num_delims;
SCM_VALIDATE_STRING (1, delims);
num_delims = scm_i_string_length (delims);
SCM_VALIDATE_STRING (2, str);
scm_i_get_substring_spec (scm_i_string_length (str),
start, &cstart, end, &cend);
if (SCM_UNBNDP (port))
port = scm_current_input_port ();
else
SCM_VALIDATE_OPINPORT (4, port);
for (j = cstart; j < cend; j++)
{
size_t k;
c = scm_getc (port);
for (k = 0; k < num_delims; k++)
{
if (scm_i_string_ref (delims, k) == c)
{
if (scm_is_false (gobble))
scm_ungetc (c, port);
return scm_cons (SCM_MAKE_CHAR (c),
scm_from_size_t (j - cstart));
}
}
if (c == EOF)
return scm_cons (SCM_EOF_VAL,
scm_from_size_t (j - cstart));
scm_c_string_set_x (str, j, SCM_MAKE_CHAR (c));
}
return scm_cons (SCM_BOOL_F, scm_from_size_t (j - cstart));
}
#undef FUNC_NAME
/*
* %read-line
* truncates any terminating newline from its input, and returns
* a cons of the string read and its terminating character. Doing
* so makes it easy to implement the hairy `read-line' options
* efficiently in Scheme.
*/
SCM_DEFINE (scm_read_line, "%read-line", 0, 1, 0,
(SCM port),
"Read a newline-terminated line from @var{port}, allocating storage as\n"
"necessary. The newline terminator (if any) is removed from the string,\n"
"and a pair consisting of the line and its delimiter is returned. The\n"
"delimiter may be either a newline or the @var{eof-object}; if\n"
"@code{%read-line} is called at the end of file, it returns the pair\n"
"@code{(#<eof> . #<eof>)}.")
#define FUNC_NAME s_scm_read_line
{
/* Threshold under which the only allocation performed is that of the
resulting string and pair. */
#define LINE_BUFFER_SIZE 256
SCM line, strings, result;
scm_t_wchar buf[LINE_BUFFER_SIZE], delim;
size_t index;
if (SCM_UNBNDP (port))
port = scm_current_input_port ();
SCM_VALIDATE_OPINPORT (1,port);
index = 0;
delim = 0;
strings = SCM_BOOL_F;
do
{
if (SCM_UNLIKELY (index >= LINE_BUFFER_SIZE))
{
/* The line is getting longer than BUF so store its current
contents in STRINGS. */
strings = scm_cons (scm_from_utf32_stringn (buf, index),
scm_is_false (strings) ? SCM_EOL : strings);
index = 0;
}
else
{
buf[index] = scm_getc (port);
switch (buf[index])
{
case EOF:
case '\n':
delim = buf[index];
break;
default:
index++;
}
}
}
while (delim == 0);
if (SCM_LIKELY (scm_is_false (strings)))
/* The fast path. */
line = scm_from_utf32_stringn (buf, index);
else
{
/* Aggregate the intermediary results. */
strings = scm_cons (scm_from_utf32_stringn (buf, index), strings);
line = scm_string_concatenate (scm_reverse (strings));
}
if (delim == EOF && scm_i_string_length (line) == 0)
result = scm_cons (SCM_EOF_VAL, SCM_EOF_VAL);
else
result = scm_cons (line,
delim == EOF ? SCM_EOF_VAL : SCM_MAKE_CHAR (delim));
return result;
#undef LINE_BUFFER_SIZE
}
#undef FUNC_NAME
SCM_DEFINE (scm_write_line, "write-line", 1, 1, 0,
(SCM obj, SCM port),
"Display @var{obj} and a newline character to @var{port}. If\n"
"@var{port} is not specified, @code{(current-output-port)} is\n"
"used. This function is equivalent to:\n"
"@lisp\n"
"(display obj [port])\n"
"(newline [port])\n"
"@end lisp")
#define FUNC_NAME s_scm_write_line
{
scm_display (obj, port);
return scm_newline (port);
}
#undef FUNC_NAME
SCM
scm_init_rdelim_builtins (void)
{
#include "libguile/rdelim.x"
return SCM_UNSPECIFIED;
}
void
scm_init_rdelim (void)
{
scm_c_define_gsubr ("%init-rdelim-builtins", 0, 0, 0,
scm_init_rdelim_builtins);
}
/*
Local Variables:
c-file-style: "gnu"
End:
*/
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