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0f3a70cfa8
R6RS character hex escapes do not conflict with legacy Guile octal character escapes, so they can be enabled by default. * libguile/read.c (scm_read_character): modified * test-suite/tests/reader.test: modify character escape tests * doc/ref/api-data.texi: modified * doc/ref/api-options.texi: modified
1762 lines
44 KiB
C
1762 lines
44 KiB
C
/* Copyright (C) 1995,1996,1997,1999,2000,2001,2003, 2004, 2006, 2007, 2008, 2009, 2010 Free Software
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* Foundation, Inc.
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public License
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* as published by the Free Software Foundation; either version 3 of
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* the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301 USA
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*/
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#ifdef HAVE_CONFIG_H
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# include <config.h>
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#endif
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#include <stdio.h>
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#include <ctype.h>
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#include <string.h>
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#include <unistd.h>
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#include <unicase.h>
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#include "libguile/_scm.h"
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#include "libguile/bytevectors.h"
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#include "libguile/chars.h"
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#include "libguile/eval.h"
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#include "libguile/arrays.h"
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#include "libguile/bitvectors.h"
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#include "libguile/keywords.h"
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#include "libguile/alist.h"
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#include "libguile/srcprop.h"
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#include "libguile/hashtab.h"
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#include "libguile/hash.h"
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#include "libguile/ports.h"
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#include "libguile/fports.h"
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#include "libguile/root.h"
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#include "libguile/strings.h"
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#include "libguile/strports.h"
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#include "libguile/vectors.h"
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#include "libguile/validate.h"
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#include "libguile/srfi-4.h"
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#include "libguile/srfi-13.h"
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#include "libguile/read.h"
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#include "libguile/private-options.h"
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SCM_GLOBAL_SYMBOL (scm_sym_dot, ".");
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SCM_SYMBOL (scm_keyword_prefix, "prefix");
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SCM_SYMBOL (scm_keyword_postfix, "postfix");
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SCM_SYMBOL (sym_nil, "nil");
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scm_t_option scm_read_opts[] = {
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{ SCM_OPTION_BOOLEAN, "copy", 0,
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"Copy source code expressions." },
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{ SCM_OPTION_BOOLEAN, "positions", 0,
|
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"Record positions of source code expressions." },
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{ SCM_OPTION_BOOLEAN, "case-insensitive", 0,
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"Convert symbols to lower case."},
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{ SCM_OPTION_SCM, "keywords", (unsigned long) SCM_BOOL_F,
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"Style of keyword recognition: #f, 'prefix or 'postfix."},
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{ SCM_OPTION_BOOLEAN, "elisp-vectors", 0,
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"Support Elisp vector syntax, namely `[...]'."},
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{ SCM_OPTION_BOOLEAN, "elisp-strings", 0,
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"Support `\\(' and `\\)' in strings."},
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{ SCM_OPTION_BOOLEAN, "r6rs-hex-escapes", 0,
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"Use R6RS variable-length character and string hex escapes."},
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{ SCM_OPTION_BOOLEAN, "square-brackets", 1,
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"Treat `[' and `]' as parentheses, for R6RS compatibility."},
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{ 0, },
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};
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/*
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Give meaningful error messages for errors
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We use the format
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FILE:LINE:COL: MESSAGE
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This happened in ....
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This is not standard GNU format, but the test-suite likes the real
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message to be in front.
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*/
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void
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scm_i_input_error (char const *function,
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SCM port, const char *message, SCM arg)
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{
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SCM fn = (scm_is_string (SCM_FILENAME(port))
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? SCM_FILENAME(port)
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: scm_from_locale_string ("#<unknown port>"));
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SCM string_port = scm_open_output_string ();
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SCM string = SCM_EOL;
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scm_simple_format (string_port,
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scm_from_locale_string ("~A:~S:~S: ~A"),
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scm_list_4 (fn,
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scm_from_long (SCM_LINUM (port) + 1),
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scm_from_int (SCM_COL (port) + 1),
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scm_from_locale_string (message)));
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string = scm_get_output_string (string_port);
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scm_close_output_port (string_port);
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scm_error_scm (scm_from_locale_symbol ("read-error"),
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function? scm_from_locale_string (function) : SCM_BOOL_F,
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string,
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arg,
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SCM_BOOL_F);
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}
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SCM_DEFINE (scm_read_options, "read-options-interface", 0, 1, 0,
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(SCM setting),
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"Option interface for the read options. Instead of using\n"
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"this procedure directly, use the procedures @code{read-enable},\n"
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"@code{read-disable}, @code{read-set!} and @code{read-options}.")
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#define FUNC_NAME s_scm_read_options
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{
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SCM ans = scm_options (setting,
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scm_read_opts,
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FUNC_NAME);
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if (SCM_COPY_SOURCE_P)
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SCM_RECORD_POSITIONS_P = 1;
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return ans;
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}
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#undef FUNC_NAME
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/* An association list mapping extra hash characters to procedures. */
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static SCM *scm_read_hash_procedures;
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/* Token readers. */
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/* Size of the C buffer used to read symbols and numbers. */
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#define READER_BUFFER_SIZE 128
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/* Size of the C buffer used to read strings. */
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#define READER_STRING_BUFFER_SIZE 512
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/* The maximum size of Scheme character names. */
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#define READER_CHAR_NAME_MAX_SIZE 50
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/* `isblank' is only in C99. */
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#define CHAR_IS_BLANK_(_chr) \
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(((_chr) == ' ') || ((_chr) == '\t') || ((_chr) == '\n') \
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|| ((_chr) == '\f') || ((_chr) == '\r'))
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#ifdef MSDOS
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# define CHAR_IS_BLANK(_chr) \
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((CHAR_IS_BLANK_ (chr)) || ((_chr) == 26))
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#else
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# define CHAR_IS_BLANK CHAR_IS_BLANK_
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#endif
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/* R5RS one-character delimiters (see section 7.1.1, ``Lexical
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structure''). */
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#define CHAR_IS_R5RS_DELIMITER(c) \
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(CHAR_IS_BLANK (c) \
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|| (c == ')') || (c == '(') || (c == ';') || (c == '"') \
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|| (SCM_SQUARE_BRACKETS_P && ((c == '[') || (c == ']'))))
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#define CHAR_IS_DELIMITER CHAR_IS_R5RS_DELIMITER
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/* Exponent markers, as defined in section 7.1.1 of R5RS, ``Lexical
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Structure''. */
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#define CHAR_IS_EXPONENT_MARKER(_chr) \
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(((_chr) == 'e') || ((_chr) == 's') || ((_chr) == 'f') \
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|| ((_chr) == 'd') || ((_chr) == 'l'))
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/* Read an SCSH block comment. */
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static inline SCM scm_read_scsh_block_comment (scm_t_wchar, SCM);
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static SCM scm_read_r6rs_block_comment (scm_t_wchar, SCM);
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static SCM scm_read_commented_expression (scm_t_wchar, SCM);
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static SCM scm_read_shebang (scm_t_wchar, SCM);
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static SCM scm_get_hash_procedure (int);
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/* Read from PORT until a delimiter (e.g., a whitespace) is read. Put the
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result in the pre-allocated buffer BUF. Return zero if the whole token has
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fewer than BUF_SIZE bytes, non-zero otherwise. READ will be set the number of
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bytes actually read. */
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static inline int
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read_token (SCM port, char *buf, const size_t buf_size, size_t *read)
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{
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*read = 0;
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while (*read < buf_size)
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{
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int chr;
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chr = scm_get_byte_or_eof (port);
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if (chr == EOF)
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return 0;
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else if (CHAR_IS_DELIMITER (chr))
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{
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scm_unget_byte (chr, port);
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return 0;
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}
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else
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{
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*buf = (char) chr;
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buf++, (*read)++;
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}
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}
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return 1;
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}
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/* Read from PORT until a delimiter (e.g., a whitespace) is read. Put the
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result in the pre-allocated buffer BUFFER, if the whole token has fewer than
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BUFFER_SIZE bytes, or into OVERFLOW_BUFFER, allocated here to be freed by the
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caller. Return zero if the token fits in BUFFER, non-zero otherwise. READ
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will be set the number of bytes actually read. */
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static int
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read_complete_token (SCM port, char *buffer, const size_t buffer_size,
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char **overflow_buffer, size_t *read)
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{
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int overflow = 0;
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size_t bytes_read, overflow_size;
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*overflow_buffer = NULL;
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overflow_size = 0;
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do
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{
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overflow = read_token (port, buffer, buffer_size, &bytes_read);
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if (bytes_read == 0)
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break;
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if (overflow || overflow_size != 0)
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{
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if (overflow_size == 0)
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{
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*overflow_buffer = scm_malloc (bytes_read);
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memcpy (*overflow_buffer, buffer, bytes_read);
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overflow_size = bytes_read;
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}
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else
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{
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*overflow_buffer = scm_realloc (*overflow_buffer, overflow_size + bytes_read);
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memcpy (*overflow_buffer + overflow_size, buffer, bytes_read);
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overflow_size += bytes_read;
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}
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}
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}
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while (overflow);
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if (overflow_size)
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*read = overflow_size;
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else
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*read = bytes_read;
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return (overflow_size != 0);
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}
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/* Skip whitespace from PORT and return the first non-whitespace character
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read. Raise an error on end-of-file. */
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static int
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flush_ws (SCM port, const char *eoferr)
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{
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register scm_t_wchar c;
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while (1)
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switch (c = scm_getc (port))
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{
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case EOF:
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goteof:
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if (eoferr)
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{
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scm_i_input_error (eoferr,
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port,
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"end of file",
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SCM_EOL);
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}
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return c;
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case ';':
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lp:
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switch (c = scm_getc (port))
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{
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case EOF:
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goto goteof;
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default:
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goto lp;
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case SCM_LINE_INCREMENTORS:
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break;
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}
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break;
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case '#':
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switch (c = scm_getc (port))
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{
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case EOF:
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eoferr = "read_sharp";
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goto goteof;
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case '!':
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scm_read_shebang (c, port);
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break;
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case ';':
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scm_read_commented_expression (c, port);
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break;
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case '|':
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if (scm_is_false (scm_get_hash_procedure (c)))
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{
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scm_read_r6rs_block_comment (c, port);
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break;
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}
|
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/* fall through */
|
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default:
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scm_ungetc (c, port);
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return '#';
|
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}
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break;
|
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|
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case SCM_LINE_INCREMENTORS:
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case SCM_SINGLE_SPACES:
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case '\t':
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break;
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default:
|
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return c;
|
||
}
|
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|
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return 0;
|
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}
|
||
|
||
|
||
|
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/* Token readers. */
|
||
|
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static SCM scm_read_expression (SCM port);
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static SCM scm_read_sharp (int chr, SCM port);
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static SCM recsexpr (SCM obj, long line, int column, SCM filename);
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|
||
|
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static SCM
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scm_read_sexp (scm_t_wchar chr, SCM port)
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#define FUNC_NAME "scm_i_lreadparen"
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{
|
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register int c;
|
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register SCM tmp;
|
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register SCM tl, ans = SCM_EOL;
|
||
SCM tl2 = SCM_EOL, ans2 = SCM_EOL, copy = SCM_BOOL_F;
|
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const int terminating_char = ((chr == '[') ? ']' : ')');
|
||
|
||
/* Need to capture line and column numbers here. */
|
||
long line = SCM_LINUM (port);
|
||
int column = SCM_COL (port) - 1;
|
||
|
||
|
||
c = flush_ws (port, FUNC_NAME);
|
||
if (terminating_char == c)
|
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return SCM_EOL;
|
||
|
||
scm_ungetc (c, port);
|
||
if (scm_is_eq (scm_sym_dot,
|
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(tmp = scm_read_expression (port))))
|
||
{
|
||
ans = scm_read_expression (port);
|
||
if (terminating_char != (c = flush_ws (port, FUNC_NAME)))
|
||
scm_i_input_error (FUNC_NAME, port, "missing close paren",
|
||
SCM_EOL);
|
||
return ans;
|
||
}
|
||
|
||
/* Build the head of the list structure. */
|
||
ans = tl = scm_cons (tmp, SCM_EOL);
|
||
|
||
if (SCM_COPY_SOURCE_P)
|
||
ans2 = tl2 = scm_cons (scm_is_pair (tmp)
|
||
? copy
|
||
: tmp,
|
||
SCM_EOL);
|
||
|
||
while (terminating_char != (c = flush_ws (port, FUNC_NAME)))
|
||
{
|
||
SCM new_tail;
|
||
|
||
if (c == ')' || (SCM_SQUARE_BRACKETS_P && c == ']'))
|
||
scm_i_input_error (FUNC_NAME, port,
|
||
"in pair: mismatched close paren: ~A",
|
||
scm_list_1 (SCM_MAKE_CHAR (c)));
|
||
|
||
scm_ungetc (c, port);
|
||
tmp = scm_read_expression (port);
|
||
|
||
if (scm_is_eq (scm_sym_dot, tmp))
|
||
{
|
||
SCM_SETCDR (tl, tmp = scm_read_expression (port));
|
||
|
||
if (SCM_COPY_SOURCE_P)
|
||
SCM_SETCDR (tl2, scm_cons (scm_is_pair (tmp) ? copy : tmp,
|
||
SCM_EOL));
|
||
|
||
c = flush_ws (port, FUNC_NAME);
|
||
if (terminating_char != c)
|
||
scm_i_input_error (FUNC_NAME, port,
|
||
"in pair: missing close paren", SCM_EOL);
|
||
goto exit;
|
||
}
|
||
|
||
new_tail = scm_cons (tmp, SCM_EOL);
|
||
SCM_SETCDR (tl, new_tail);
|
||
tl = new_tail;
|
||
|
||
if (SCM_COPY_SOURCE_P)
|
||
{
|
||
SCM new_tail2 = scm_cons (scm_is_pair (tmp)
|
||
? copy
|
||
: tmp, SCM_EOL);
|
||
SCM_SETCDR (tl2, new_tail2);
|
||
tl2 = new_tail2;
|
||
}
|
||
}
|
||
|
||
exit:
|
||
if (SCM_RECORD_POSITIONS_P)
|
||
scm_whash_insert (scm_source_whash,
|
||
ans,
|
||
scm_make_srcprops (line, column,
|
||
SCM_FILENAME (port),
|
||
SCM_COPY_SOURCE_P
|
||
? ans2
|
||
: SCM_UNDEFINED,
|
||
SCM_EOL));
|
||
return ans;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
|
||
/* Read a hexadecimal number NDIGITS in length. Put its value into the variable
|
||
C. If TERMINATOR is non-null, terminate early if the TERMINATOR character is
|
||
found. */
|
||
#define SCM_READ_HEX_ESCAPE(ndigits, terminator) \
|
||
do \
|
||
{ \
|
||
scm_t_wchar a; \
|
||
size_t i = 0; \
|
||
c = 0; \
|
||
while (i < ndigits) \
|
||
{ \
|
||
a = scm_getc (port); \
|
||
if (a == EOF) \
|
||
goto str_eof; \
|
||
if (terminator \
|
||
&& (a == (scm_t_wchar) terminator) \
|
||
&& (i > 0)) \
|
||
break; \
|
||
if ('0' <= a && a <= '9') \
|
||
a -= '0'; \
|
||
else if ('A' <= a && a <= 'F') \
|
||
a = a - 'A' + 10; \
|
||
else if ('a' <= a && a <= 'f') \
|
||
a = a - 'a' + 10; \
|
||
else \
|
||
{ \
|
||
c = a; \
|
||
goto bad_escaped; \
|
||
} \
|
||
c = c * 16 + a; \
|
||
i ++; \
|
||
} \
|
||
} while (0)
|
||
|
||
static SCM
|
||
scm_read_string (int chr, SCM port)
|
||
#define FUNC_NAME "scm_lreadr"
|
||
{
|
||
/* For strings smaller than C_STR, this function creates only one Scheme
|
||
object (the string returned). */
|
||
|
||
SCM str = SCM_BOOL_F;
|
||
unsigned c_str_len = 0;
|
||
scm_t_wchar c;
|
||
|
||
str = scm_i_make_string (READER_STRING_BUFFER_SIZE, NULL);
|
||
while ('"' != (c = scm_getc (port)))
|
||
{
|
||
if (c == EOF)
|
||
{
|
||
str_eof:
|
||
scm_i_input_error (FUNC_NAME, port,
|
||
"end of file in string constant", SCM_EOL);
|
||
}
|
||
|
||
if (c_str_len + 1 >= scm_i_string_length (str))
|
||
{
|
||
SCM addy = scm_i_make_string (READER_STRING_BUFFER_SIZE, NULL);
|
||
|
||
str = scm_string_append (scm_list_2 (str, addy));
|
||
}
|
||
|
||
if (c == '\\')
|
||
{
|
||
switch (c = scm_getc (port))
|
||
{
|
||
case EOF:
|
||
goto str_eof;
|
||
case '"':
|
||
case '\\':
|
||
break;
|
||
case '(':
|
||
case ')':
|
||
if (SCM_ESCAPED_PARENS_P)
|
||
break;
|
||
goto bad_escaped;
|
||
case '\n':
|
||
continue;
|
||
case '0':
|
||
c = '\0';
|
||
break;
|
||
case 'f':
|
||
c = '\f';
|
||
break;
|
||
case 'n':
|
||
c = '\n';
|
||
break;
|
||
case 'r':
|
||
c = '\r';
|
||
break;
|
||
case 't':
|
||
c = '\t';
|
||
break;
|
||
case 'a':
|
||
c = '\007';
|
||
break;
|
||
case 'v':
|
||
c = '\v';
|
||
break;
|
||
case 'b':
|
||
c = '\010';
|
||
break;
|
||
case 'x':
|
||
if (SCM_R6RS_ESCAPES_P)
|
||
SCM_READ_HEX_ESCAPE (10, ';');
|
||
else
|
||
SCM_READ_HEX_ESCAPE (2, '\0');
|
||
break;
|
||
case 'u':
|
||
if (!SCM_R6RS_ESCAPES_P)
|
||
{
|
||
SCM_READ_HEX_ESCAPE (4, '\0');
|
||
break;
|
||
}
|
||
case 'U':
|
||
if (!SCM_R6RS_ESCAPES_P)
|
||
{
|
||
SCM_READ_HEX_ESCAPE (6, '\0');
|
||
break;
|
||
}
|
||
default:
|
||
bad_escaped:
|
||
scm_i_input_error (FUNC_NAME, port,
|
||
"illegal character in escape sequence: ~S",
|
||
scm_list_1 (SCM_MAKE_CHAR (c)));
|
||
}
|
||
}
|
||
str = scm_i_string_start_writing (str);
|
||
scm_i_string_set_x (str, c_str_len++, c);
|
||
scm_i_string_stop_writing ();
|
||
}
|
||
|
||
if (c_str_len > 0)
|
||
{
|
||
return scm_i_substring_copy (str, 0, c_str_len);
|
||
}
|
||
|
||
return scm_nullstr;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
|
||
static SCM
|
||
scm_read_number (scm_t_wchar chr, SCM port)
|
||
{
|
||
SCM result, str = SCM_EOL;
|
||
char buffer[READER_BUFFER_SIZE];
|
||
char *overflow_buffer = NULL;
|
||
size_t bytes_read;
|
||
int overflow;
|
||
scm_t_port *pt = SCM_PTAB_ENTRY (port);
|
||
|
||
scm_ungetc (chr, port);
|
||
overflow = read_complete_token (port, buffer, sizeof (buffer),
|
||
&overflow_buffer, &bytes_read);
|
||
|
||
if (!overflow)
|
||
str = scm_from_stringn (buffer, bytes_read, pt->encoding, pt->ilseq_handler);
|
||
else
|
||
str = scm_from_stringn (overflow_buffer, bytes_read, pt->encoding,
|
||
pt->ilseq_handler);
|
||
|
||
result = scm_string_to_number (str, SCM_UNDEFINED);
|
||
if (!scm_is_true (result))
|
||
{
|
||
/* Return a symbol instead of a number */
|
||
if (SCM_CASE_INSENSITIVE_P)
|
||
str = scm_string_downcase_x (str);
|
||
result = scm_string_to_symbol (str);
|
||
}
|
||
|
||
if (overflow)
|
||
free (overflow_buffer);
|
||
SCM_COL (port) += scm_i_string_length (str);
|
||
return result;
|
||
}
|
||
|
||
static SCM
|
||
scm_read_mixed_case_symbol (scm_t_wchar chr, SCM port)
|
||
{
|
||
SCM result;
|
||
int ends_with_colon = 0;
|
||
size_t bytes_read;
|
||
int postfix = scm_is_eq (SCM_PACK (SCM_KEYWORD_STYLE), scm_keyword_postfix);
|
||
int overflow;
|
||
char buffer[READER_BUFFER_SIZE], *overflow_buffer;
|
||
scm_t_port *pt = SCM_PTAB_ENTRY (port);
|
||
SCM str;
|
||
|
||
scm_ungetc (chr, port);
|
||
overflow = read_complete_token (port, buffer, READER_BUFFER_SIZE,
|
||
&overflow_buffer, &bytes_read);
|
||
if (bytes_read > 0)
|
||
{
|
||
if (!overflow)
|
||
ends_with_colon = buffer[bytes_read - 1] == ':';
|
||
else
|
||
ends_with_colon = overflow_buffer[bytes_read - 1] == ':';
|
||
}
|
||
|
||
if (postfix && ends_with_colon && (bytes_read > 1))
|
||
{
|
||
if (!overflow)
|
||
str = scm_from_stringn (buffer, bytes_read - 1, pt->encoding, pt->ilseq_handler);
|
||
else
|
||
str = scm_from_stringn (overflow_buffer, bytes_read - 1, pt->encoding,
|
||
pt->ilseq_handler);
|
||
|
||
if (SCM_CASE_INSENSITIVE_P)
|
||
str = scm_string_downcase_x (str);
|
||
result = scm_symbol_to_keyword (scm_string_to_symbol (str));
|
||
}
|
||
else
|
||
{
|
||
if (!overflow)
|
||
str = scm_from_stringn (buffer, bytes_read, pt->encoding, pt->ilseq_handler);
|
||
else
|
||
str = scm_from_stringn (overflow_buffer, bytes_read, pt->encoding,
|
||
pt->ilseq_handler);
|
||
|
||
if (SCM_CASE_INSENSITIVE_P)
|
||
str = scm_string_downcase_x (str);
|
||
result = scm_string_to_symbol (str);
|
||
}
|
||
|
||
if (overflow)
|
||
free (overflow_buffer);
|
||
SCM_COL (port) += scm_i_string_length (str);
|
||
return result;
|
||
}
|
||
|
||
static SCM
|
||
scm_read_number_and_radix (scm_t_wchar chr, SCM port)
|
||
#define FUNC_NAME "scm_lreadr"
|
||
{
|
||
SCM result;
|
||
size_t read;
|
||
char buffer[READER_BUFFER_SIZE], *overflow_buffer;
|
||
int overflow;
|
||
unsigned int radix;
|
||
SCM str;
|
||
scm_t_port *pt;
|
||
|
||
switch (chr)
|
||
{
|
||
case 'B':
|
||
case 'b':
|
||
radix = 2;
|
||
break;
|
||
|
||
case 'o':
|
||
case 'O':
|
||
radix = 8;
|
||
break;
|
||
|
||
case 'd':
|
||
case 'D':
|
||
radix = 10;
|
||
break;
|
||
|
||
case 'x':
|
||
case 'X':
|
||
radix = 16;
|
||
break;
|
||
|
||
default:
|
||
scm_ungetc (chr, port);
|
||
scm_ungetc ('#', port);
|
||
radix = 10;
|
||
}
|
||
|
||
overflow = read_complete_token (port, buffer, sizeof (buffer),
|
||
&overflow_buffer, &read);
|
||
|
||
pt = SCM_PTAB_ENTRY (port);
|
||
if (!overflow)
|
||
str = scm_from_stringn (buffer, read, pt->encoding, pt->ilseq_handler);
|
||
else
|
||
str = scm_from_stringn (overflow_buffer, read, pt->encoding,
|
||
pt->ilseq_handler);
|
||
|
||
result = scm_string_to_number (str, scm_from_uint (radix));
|
||
|
||
if (overflow)
|
||
free (overflow_buffer);
|
||
|
||
SCM_COL (port) += scm_i_string_length (str);
|
||
|
||
if (scm_is_true (result))
|
||
return result;
|
||
|
||
scm_i_input_error (FUNC_NAME, port, "unknown # object", SCM_EOL);
|
||
|
||
return SCM_BOOL_F;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
static SCM
|
||
scm_read_quote (int chr, SCM port)
|
||
{
|
||
SCM p;
|
||
long line = SCM_LINUM (port);
|
||
int column = SCM_COL (port) - 1;
|
||
|
||
switch (chr)
|
||
{
|
||
case '`':
|
||
p = scm_sym_quasiquote;
|
||
break;
|
||
|
||
case '\'':
|
||
p = scm_sym_quote;
|
||
break;
|
||
|
||
case ',':
|
||
{
|
||
scm_t_wchar c;
|
||
|
||
c = scm_getc (port);
|
||
if ('@' == c)
|
||
p = scm_sym_uq_splicing;
|
||
else
|
||
{
|
||
scm_ungetc (c, port);
|
||
p = scm_sym_unquote;
|
||
}
|
||
break;
|
||
}
|
||
|
||
default:
|
||
fprintf (stderr, "%s: unhandled quote character (%i)\n",
|
||
"scm_read_quote", chr);
|
||
abort ();
|
||
}
|
||
|
||
p = scm_cons2 (p, scm_read_expression (port), SCM_EOL);
|
||
if (SCM_RECORD_POSITIONS_P)
|
||
scm_whash_insert (scm_source_whash, p,
|
||
scm_make_srcprops (line, column,
|
||
SCM_FILENAME (port),
|
||
SCM_COPY_SOURCE_P
|
||
? (scm_cons2 (SCM_CAR (p),
|
||
SCM_CAR (SCM_CDR (p)),
|
||
SCM_EOL))
|
||
: SCM_UNDEFINED,
|
||
SCM_EOL));
|
||
|
||
|
||
return p;
|
||
}
|
||
|
||
SCM_SYMBOL (sym_syntax, "syntax");
|
||
SCM_SYMBOL (sym_quasisyntax, "quasisyntax");
|
||
SCM_SYMBOL (sym_unsyntax, "unsyntax");
|
||
SCM_SYMBOL (sym_unsyntax_splicing, "unsyntax-splicing");
|
||
|
||
static SCM
|
||
scm_read_syntax (int chr, SCM port)
|
||
{
|
||
SCM p;
|
||
long line = SCM_LINUM (port);
|
||
int column = SCM_COL (port) - 1;
|
||
|
||
switch (chr)
|
||
{
|
||
case '`':
|
||
p = sym_quasisyntax;
|
||
break;
|
||
|
||
case '\'':
|
||
p = sym_syntax;
|
||
break;
|
||
|
||
case ',':
|
||
{
|
||
int c;
|
||
|
||
c = scm_getc (port);
|
||
if ('@' == c)
|
||
p = sym_unsyntax_splicing;
|
||
else
|
||
{
|
||
scm_ungetc (c, port);
|
||
p = sym_unsyntax;
|
||
}
|
||
break;
|
||
}
|
||
|
||
default:
|
||
fprintf (stderr, "%s: unhandled syntax character (%i)\n",
|
||
"scm_read_syntax", chr);
|
||
abort ();
|
||
}
|
||
|
||
p = scm_cons2 (p, scm_read_expression (port), SCM_EOL);
|
||
if (SCM_RECORD_POSITIONS_P)
|
||
scm_whash_insert (scm_source_whash, p,
|
||
scm_make_srcprops (line, column,
|
||
SCM_FILENAME (port),
|
||
SCM_COPY_SOURCE_P
|
||
? (scm_cons2 (SCM_CAR (p),
|
||
SCM_CAR (SCM_CDR (p)),
|
||
SCM_EOL))
|
||
: SCM_UNDEFINED,
|
||
SCM_EOL));
|
||
|
||
|
||
return p;
|
||
}
|
||
|
||
static inline SCM
|
||
scm_read_nil (int chr, SCM port)
|
||
{
|
||
SCM id = scm_read_mixed_case_symbol (chr, port);
|
||
|
||
if (!scm_is_eq (id, sym_nil))
|
||
scm_i_input_error ("scm_read_nil", port,
|
||
"unexpected input while reading #nil: ~a",
|
||
scm_list_1 (id));
|
||
|
||
return SCM_ELISP_NIL;
|
||
}
|
||
|
||
static inline SCM
|
||
scm_read_semicolon_comment (int chr, SCM port)
|
||
{
|
||
int c;
|
||
|
||
/* We use the get_byte here because there is no need to get the
|
||
locale correct with comment input. This presumes that newline
|
||
always represents itself no matter what the encoding is. */
|
||
for (c = scm_get_byte_or_eof (port);
|
||
(c != EOF) && (c != '\n');
|
||
c = scm_get_byte_or_eof (port));
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
|
||
/* Sharp readers, i.e. readers called after a `#' sign has been read. */
|
||
|
||
static SCM
|
||
scm_read_boolean (int chr, SCM port)
|
||
{
|
||
switch (chr)
|
||
{
|
||
case 't':
|
||
case 'T':
|
||
return SCM_BOOL_T;
|
||
|
||
case 'f':
|
||
case 'F':
|
||
return SCM_BOOL_F;
|
||
}
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
static SCM
|
||
scm_read_character (scm_t_wchar chr, SCM port)
|
||
#define FUNC_NAME "scm_lreadr"
|
||
{
|
||
char buffer[READER_CHAR_NAME_MAX_SIZE];
|
||
SCM charname;
|
||
size_t charname_len, bytes_read;
|
||
scm_t_wchar cp;
|
||
int overflow;
|
||
scm_t_port *pt;
|
||
|
||
overflow = read_token (port, buffer, READER_CHAR_NAME_MAX_SIZE, &bytes_read);
|
||
if (overflow)
|
||
goto char_error;
|
||
|
||
if (bytes_read == 0)
|
||
{
|
||
chr = scm_getc (port);
|
||
if (chr == EOF)
|
||
scm_i_input_error (FUNC_NAME, port, "unexpected end of file "
|
||
"while reading character", SCM_EOL);
|
||
|
||
/* CHR must be a token delimiter, like a whitespace. */
|
||
return (SCM_MAKE_CHAR (chr));
|
||
}
|
||
|
||
pt = SCM_PTAB_ENTRY (port);
|
||
|
||
/* Simple ASCII characters can be processed immediately. Also, simple
|
||
ISO-8859-1 characters can be processed immediately if the encoding for this
|
||
port is ISO-8859-1. */
|
||
if (bytes_read == 1 && ((unsigned char) buffer[0] <= 127 || pt->encoding == NULL))
|
||
{
|
||
SCM_COL (port) += 1;
|
||
return SCM_MAKE_CHAR (buffer[0]);
|
||
}
|
||
|
||
/* Otherwise, convert the buffer into a proper scheme string for
|
||
processing. */
|
||
charname = scm_from_stringn (buffer, bytes_read, pt->encoding,
|
||
pt->ilseq_handler);
|
||
charname_len = scm_i_string_length (charname);
|
||
SCM_COL (port) += charname_len;
|
||
cp = scm_i_string_ref (charname, 0);
|
||
if (charname_len == 1)
|
||
return SCM_MAKE_CHAR (cp);
|
||
|
||
/* Ignore dotted circles, which may be used to keep combining characters from
|
||
combining with the backslash in #\charname. */
|
||
if (cp == SCM_CODEPOINT_DOTTED_CIRCLE && charname_len == 2)
|
||
return SCM_MAKE_CHAR (scm_i_string_ref (charname, 1));
|
||
|
||
if (cp >= '0' && cp < '8')
|
||
{
|
||
/* Dirk:FIXME:: This type of character syntax is not R5RS
|
||
* compliant. Further, it should be verified that the constant
|
||
* does only consist of octal digits. */
|
||
SCM p = scm_string_to_number (charname, scm_from_uint (8));
|
||
if (SCM_I_INUMP (p))
|
||
{
|
||
scm_t_wchar c = SCM_I_INUM (p);
|
||
if (SCM_IS_UNICODE_CHAR (c))
|
||
return SCM_MAKE_CHAR (c);
|
||
else
|
||
scm_i_input_error (FUNC_NAME, port,
|
||
"out-of-range octal character escape: ~a",
|
||
scm_list_1 (charname));
|
||
}
|
||
}
|
||
|
||
if (cp == 'x' && (charname_len > 1))
|
||
{
|
||
SCM p;
|
||
|
||
/* Convert from hex, skipping the initial 'x' character in CHARNAME */
|
||
p = scm_string_to_number (scm_c_substring (charname, 1, charname_len),
|
||
scm_from_uint (16));
|
||
if (SCM_I_INUMP (p))
|
||
{
|
||
scm_t_wchar c = SCM_I_INUM (p);
|
||
if (SCM_IS_UNICODE_CHAR (c))
|
||
return SCM_MAKE_CHAR (c);
|
||
else
|
||
scm_i_input_error (FUNC_NAME, port,
|
||
"out-of-range hex character escape: ~a",
|
||
scm_list_1 (charname));
|
||
}
|
||
}
|
||
|
||
/* The names of characters should never have non-Latin1
|
||
characters. */
|
||
if (scm_i_is_narrow_string (charname)
|
||
|| scm_i_try_narrow_string (charname))
|
||
{ SCM ch = scm_i_charname_to_char (scm_i_string_chars (charname),
|
||
charname_len);
|
||
if (scm_is_true (ch))
|
||
return ch;
|
||
}
|
||
|
||
char_error:
|
||
scm_i_input_error (FUNC_NAME, port, "unknown character name ~a",
|
||
scm_list_1 (charname));
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
static inline SCM
|
||
scm_read_keyword (int chr, SCM port)
|
||
{
|
||
SCM symbol;
|
||
|
||
/* Read the symbol that comprises the keyword. Doing this instead of
|
||
invoking a specific symbol reader function allows `scm_read_keyword ()'
|
||
to adapt to the delimiters currently valid of symbols.
|
||
|
||
XXX: This implementation allows sloppy syntaxes like `#: key'. */
|
||
symbol = scm_read_expression (port);
|
||
if (!scm_is_symbol (symbol))
|
||
scm_i_input_error ("scm_read_keyword", port,
|
||
"keyword prefix `~a' not followed by a symbol: ~s",
|
||
scm_list_2 (SCM_MAKE_CHAR (chr), symbol));
|
||
|
||
return (scm_symbol_to_keyword (symbol));
|
||
}
|
||
|
||
static inline SCM
|
||
scm_read_vector (int chr, SCM port)
|
||
{
|
||
/* Note: We call `scm_read_sexp ()' rather than READER here in order to
|
||
guarantee that it's going to do what we want. After all, this is an
|
||
implementation detail of `scm_read_vector ()', not a desirable
|
||
property. */
|
||
return (scm_vector (scm_read_sexp (chr, port)));
|
||
}
|
||
|
||
static inline SCM
|
||
scm_read_srfi4_vector (int chr, SCM port)
|
||
{
|
||
return scm_i_read_array (port, chr);
|
||
}
|
||
|
||
static SCM
|
||
scm_read_bytevector (scm_t_wchar chr, SCM port)
|
||
{
|
||
chr = scm_getc (port);
|
||
if (chr != 'u')
|
||
goto syntax;
|
||
|
||
chr = scm_getc (port);
|
||
if (chr != '8')
|
||
goto syntax;
|
||
|
||
chr = scm_getc (port);
|
||
if (chr != '(')
|
||
goto syntax;
|
||
|
||
return scm_u8_list_to_bytevector (scm_read_sexp (chr, port));
|
||
|
||
syntax:
|
||
scm_i_input_error ("read_bytevector", port,
|
||
"invalid bytevector prefix",
|
||
SCM_MAKE_CHAR (chr));
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
static SCM
|
||
scm_read_guile_bit_vector (scm_t_wchar chr, SCM port)
|
||
{
|
||
/* Read the `#*10101'-style read syntax for bit vectors in Guile. This is
|
||
terribly inefficient but who cares? */
|
||
SCM s_bits = SCM_EOL;
|
||
|
||
for (chr = scm_getc (port);
|
||
(chr != EOF) && ((chr == '0') || (chr == '1'));
|
||
chr = scm_getc (port))
|
||
{
|
||
s_bits = scm_cons ((chr == '0') ? SCM_BOOL_F : SCM_BOOL_T, s_bits);
|
||
}
|
||
|
||
if (chr != EOF)
|
||
scm_ungetc (chr, port);
|
||
|
||
return scm_bitvector (scm_reverse_x (s_bits, SCM_EOL));
|
||
}
|
||
|
||
static inline SCM
|
||
scm_read_scsh_block_comment (scm_t_wchar chr, SCM port)
|
||
{
|
||
int bang_seen = 0;
|
||
|
||
/* We can use the get_byte here because there is no need to get the
|
||
locale correct when reading comments. This presumes that
|
||
hash and exclamation points always represent themselves no
|
||
matter what the source encoding is.*/
|
||
for (;;)
|
||
{
|
||
int c = scm_get_byte_or_eof (port);
|
||
|
||
if (c == EOF)
|
||
scm_i_input_error ("skip_block_comment", port,
|
||
"unterminated `#! ... !#' comment", SCM_EOL);
|
||
|
||
if (c == '!')
|
||
bang_seen = 1;
|
||
else if (c == '#' && bang_seen)
|
||
break;
|
||
else
|
||
bang_seen = 0;
|
||
}
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
static inline SCM
|
||
scm_read_shebang (scm_t_wchar chr, SCM port)
|
||
{
|
||
int c = 0;
|
||
if ((c = scm_get_byte_or_eof (port)) != 'r')
|
||
{
|
||
scm_ungetc (c, port);
|
||
return scm_read_scsh_block_comment (chr, port);
|
||
}
|
||
if ((c = scm_get_byte_or_eof (port)) != '6')
|
||
{
|
||
scm_ungetc (c, port);
|
||
scm_ungetc ('r', port);
|
||
return scm_read_scsh_block_comment (chr, port);
|
||
}
|
||
if ((c = scm_get_byte_or_eof (port)) != 'r')
|
||
{
|
||
scm_ungetc (c, port);
|
||
scm_ungetc ('6', port);
|
||
scm_ungetc ('r', port);
|
||
return scm_read_scsh_block_comment (chr, port);
|
||
}
|
||
if ((c = scm_get_byte_or_eof (port)) != 's')
|
||
{
|
||
scm_ungetc (c, port);
|
||
scm_ungetc ('r', port);
|
||
scm_ungetc ('6', port);
|
||
scm_ungetc ('r', port);
|
||
return scm_read_scsh_block_comment (chr, port);
|
||
}
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
static SCM
|
||
scm_read_r6rs_block_comment (scm_t_wchar chr, SCM port)
|
||
{
|
||
/* Unlike SCSH-style block comments, SRFI-30/R6RS block comments may be
|
||
nested. So care must be taken. */
|
||
int nesting_level = 1;
|
||
int opening_seen = 0, closing_seen = 0;
|
||
|
||
while (nesting_level > 0)
|
||
{
|
||
int c = scm_getc (port);
|
||
|
||
if (c == EOF)
|
||
scm_i_input_error ("scm_read_r6rs_block_comment", port,
|
||
"unterminated `#| ... |#' comment", SCM_EOL);
|
||
|
||
if (opening_seen)
|
||
{
|
||
if (c == '|')
|
||
nesting_level++;
|
||
opening_seen = 0;
|
||
}
|
||
else if (closing_seen)
|
||
{
|
||
if (c == '#')
|
||
nesting_level--;
|
||
closing_seen = 0;
|
||
}
|
||
else if (c == '|')
|
||
closing_seen = 1;
|
||
else if (c == '#')
|
||
opening_seen = 1;
|
||
else
|
||
opening_seen = closing_seen = 0;
|
||
}
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
static SCM
|
||
scm_read_commented_expression (scm_t_wchar chr, SCM port)
|
||
{
|
||
scm_t_wchar c;
|
||
|
||
c = flush_ws (port, (char *) NULL);
|
||
if (EOF == c)
|
||
scm_i_input_error ("read_commented_expression", port,
|
||
"no expression after #; comment", SCM_EOL);
|
||
scm_ungetc (c, port);
|
||
scm_read_expression (port);
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
static SCM
|
||
scm_read_extended_symbol (scm_t_wchar chr, SCM port)
|
||
{
|
||
/* Guile's extended symbol read syntax looks like this:
|
||
|
||
#{This is all a symbol name}#
|
||
|
||
So here, CHR is expected to be `{'. */
|
||
int saw_brace = 0, finished = 0;
|
||
size_t len = 0;
|
||
SCM buf = scm_i_make_string (1024, NULL);
|
||
|
||
buf = scm_i_string_start_writing (buf);
|
||
|
||
while ((chr = scm_getc (port)) != EOF)
|
||
{
|
||
if (saw_brace)
|
||
{
|
||
if (chr == '#')
|
||
{
|
||
finished = 1;
|
||
break;
|
||
}
|
||
else
|
||
{
|
||
saw_brace = 0;
|
||
scm_i_string_set_x (buf, len++, '}');
|
||
scm_i_string_set_x (buf, len++, chr);
|
||
}
|
||
}
|
||
else if (chr == '}')
|
||
saw_brace = 1;
|
||
else
|
||
scm_i_string_set_x (buf, len++, chr);
|
||
|
||
if (len >= scm_i_string_length (buf) - 2)
|
||
{
|
||
SCM addy;
|
||
|
||
scm_i_string_stop_writing ();
|
||
addy = scm_i_make_string (1024, NULL);
|
||
buf = scm_string_append (scm_list_2 (buf, addy));
|
||
len = 0;
|
||
buf = scm_i_string_start_writing (buf);
|
||
}
|
||
|
||
if (finished)
|
||
break;
|
||
}
|
||
scm_i_string_stop_writing ();
|
||
|
||
return (scm_string_to_symbol (scm_c_substring (buf, 0, len)));
|
||
}
|
||
|
||
|
||
|
||
/* Top-level token readers, i.e., dispatchers. */
|
||
|
||
static SCM
|
||
scm_read_sharp_extension (int chr, SCM port)
|
||
{
|
||
SCM proc;
|
||
|
||
proc = scm_get_hash_procedure (chr);
|
||
if (scm_is_true (scm_procedure_p (proc)))
|
||
{
|
||
long line = SCM_LINUM (port);
|
||
int column = SCM_COL (port) - 2;
|
||
SCM got;
|
||
|
||
got = scm_call_2 (proc, SCM_MAKE_CHAR (chr), port);
|
||
if (!scm_is_eq (got, SCM_UNSPECIFIED))
|
||
{
|
||
if (SCM_RECORD_POSITIONS_P)
|
||
return (recsexpr (got, line, column,
|
||
SCM_FILENAME (port)));
|
||
else
|
||
return got;
|
||
}
|
||
}
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
|
||
/* The reader for the sharp `#' character. It basically dispatches reads
|
||
among the above token readers. */
|
||
static SCM
|
||
scm_read_sharp (scm_t_wchar chr, SCM port)
|
||
#define FUNC_NAME "scm_lreadr"
|
||
{
|
||
SCM result;
|
||
|
||
chr = scm_getc (port);
|
||
|
||
result = scm_read_sharp_extension (chr, port);
|
||
if (!scm_is_eq (result, SCM_UNSPECIFIED))
|
||
return result;
|
||
|
||
switch (chr)
|
||
{
|
||
case '\\':
|
||
return (scm_read_character (chr, port));
|
||
case '(':
|
||
return (scm_read_vector (chr, port));
|
||
case 's':
|
||
case 'u':
|
||
case 'f':
|
||
/* This one may return either a boolean or an SRFI-4 vector. */
|
||
return (scm_read_srfi4_vector (chr, port));
|
||
case 'v':
|
||
return (scm_read_bytevector (chr, port));
|
||
case '*':
|
||
return (scm_read_guile_bit_vector (chr, port));
|
||
case 't':
|
||
case 'T':
|
||
case 'F':
|
||
/* This one may return either a boolean or an SRFI-4 vector. */
|
||
return (scm_read_boolean (chr, port));
|
||
case ':':
|
||
return (scm_read_keyword (chr, port));
|
||
case '0': case '1': case '2': case '3': case '4':
|
||
case '5': case '6': case '7': case '8': case '9':
|
||
case '@':
|
||
#if SCM_ENABLE_DEPRECATED
|
||
/* See below for 'i' and 'e'. */
|
||
case 'a':
|
||
case 'c':
|
||
case 'y':
|
||
case 'h':
|
||
case 'l':
|
||
#endif
|
||
return (scm_i_read_array (port, chr));
|
||
|
||
case 'i':
|
||
case 'e':
|
||
#if SCM_ENABLE_DEPRECATED
|
||
{
|
||
/* When next char is '(', it really is an old-style
|
||
uniform array. */
|
||
scm_t_wchar next_c = scm_getc (port);
|
||
if (next_c != EOF)
|
||
scm_ungetc (next_c, port);
|
||
if (next_c == '(')
|
||
return scm_i_read_array (port, chr);
|
||
/* Fall through. */
|
||
}
|
||
#endif
|
||
case 'b':
|
||
case 'B':
|
||
case 'o':
|
||
case 'O':
|
||
case 'd':
|
||
case 'D':
|
||
case 'x':
|
||
case 'X':
|
||
case 'I':
|
||
case 'E':
|
||
return (scm_read_number_and_radix (chr, port));
|
||
case '{':
|
||
return (scm_read_extended_symbol (chr, port));
|
||
case '!':
|
||
return (scm_read_shebang (chr, port));
|
||
case ';':
|
||
return (scm_read_commented_expression (chr, port));
|
||
case '`':
|
||
case '\'':
|
||
case ',':
|
||
return (scm_read_syntax (chr, port));
|
||
case 'n':
|
||
return (scm_read_nil (chr, port));
|
||
default:
|
||
result = scm_read_sharp_extension (chr, port);
|
||
if (scm_is_eq (result, SCM_UNSPECIFIED))
|
||
{
|
||
/* To remain compatible with 1.8 and earlier, the following
|
||
characters have lower precedence than `read-hash-extend'
|
||
characters. */
|
||
switch (chr)
|
||
{
|
||
case '|':
|
||
return scm_read_r6rs_block_comment (chr, port);
|
||
default:
|
||
scm_i_input_error (FUNC_NAME, port, "Unknown # object: ~S",
|
||
scm_list_1 (SCM_MAKE_CHAR (chr)));
|
||
}
|
||
}
|
||
else
|
||
return result;
|
||
}
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
static SCM
|
||
scm_read_expression (SCM port)
|
||
#define FUNC_NAME "scm_read_expression"
|
||
{
|
||
while (1)
|
||
{
|
||
register scm_t_wchar chr;
|
||
|
||
chr = scm_getc (port);
|
||
|
||
switch (chr)
|
||
{
|
||
case SCM_WHITE_SPACES:
|
||
case SCM_LINE_INCREMENTORS:
|
||
break;
|
||
case ';':
|
||
(void) scm_read_semicolon_comment (chr, port);
|
||
break;
|
||
case '[':
|
||
if (!SCM_SQUARE_BRACKETS_P)
|
||
return (scm_read_mixed_case_symbol (chr, port));
|
||
/* otherwise fall through */
|
||
case '(':
|
||
return (scm_read_sexp (chr, port));
|
||
case '"':
|
||
return (scm_read_string (chr, port));
|
||
case '\'':
|
||
case '`':
|
||
case ',':
|
||
return (scm_read_quote (chr, port));
|
||
case '#':
|
||
{
|
||
SCM result;
|
||
result = scm_read_sharp (chr, port);
|
||
if (scm_is_eq (result, SCM_UNSPECIFIED))
|
||
/* We read a comment or some such. */
|
||
break;
|
||
else
|
||
return result;
|
||
}
|
||
case ')':
|
||
scm_i_input_error (FUNC_NAME, port, "unexpected \")\"", SCM_EOL);
|
||
break;
|
||
case EOF:
|
||
return SCM_EOF_VAL;
|
||
case ':':
|
||
if (scm_is_eq (SCM_PACK (SCM_KEYWORD_STYLE), scm_keyword_prefix))
|
||
return scm_symbol_to_keyword (scm_read_expression (port));
|
||
/* Fall through. */
|
||
|
||
default:
|
||
{
|
||
if (((chr >= '0') && (chr <= '9'))
|
||
|| (strchr ("+-.", chr)))
|
||
return (scm_read_number (chr, port));
|
||
else
|
||
return (scm_read_mixed_case_symbol (chr, port));
|
||
}
|
||
}
|
||
}
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
|
||
/* Actual reader. */
|
||
|
||
SCM_DEFINE (scm_read, "read", 0, 1, 0,
|
||
(SCM port),
|
||
"Read an s-expression from the input port @var{port}, or from\n"
|
||
"the current input port if @var{port} is not specified.\n"
|
||
"Any whitespace before the next token is discarded.")
|
||
#define FUNC_NAME s_scm_read
|
||
{
|
||
int c;
|
||
|
||
if (SCM_UNBNDP (port))
|
||
port = scm_current_input_port ();
|
||
SCM_VALIDATE_OPINPORT (1, port);
|
||
|
||
c = flush_ws (port, (char *) NULL);
|
||
if (EOF == c)
|
||
return SCM_EOF_VAL;
|
||
scm_ungetc (c, port);
|
||
|
||
return (scm_read_expression (port));
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
|
||
|
||
|
||
/* Used when recording expressions constructed by `scm_read_sharp ()'. */
|
||
static SCM
|
||
recsexpr (SCM obj, long line, int column, SCM filename)
|
||
{
|
||
if (!scm_is_pair(obj)) {
|
||
return obj;
|
||
} else {
|
||
SCM tmp = obj, copy;
|
||
/* If this sexpr is visible in the read:sharp source, we want to
|
||
keep that information, so only record non-constant cons cells
|
||
which haven't previously been read by the reader. */
|
||
if (scm_is_false (scm_whash_lookup (scm_source_whash, obj)))
|
||
{
|
||
if (SCM_COPY_SOURCE_P)
|
||
{
|
||
copy = scm_cons (recsexpr (SCM_CAR (obj), line, column, filename),
|
||
SCM_UNDEFINED);
|
||
while ((tmp = SCM_CDR (tmp)) && scm_is_pair (tmp))
|
||
{
|
||
SCM_SETCDR (copy, scm_cons (recsexpr (SCM_CAR (tmp),
|
||
line,
|
||
column,
|
||
filename),
|
||
SCM_UNDEFINED));
|
||
copy = SCM_CDR (copy);
|
||
}
|
||
SCM_SETCDR (copy, tmp);
|
||
}
|
||
else
|
||
{
|
||
recsexpr (SCM_CAR (obj), line, column, filename);
|
||
while ((tmp = SCM_CDR (tmp)) && scm_is_pair (tmp))
|
||
recsexpr (SCM_CAR (tmp), line, column, filename);
|
||
copy = SCM_UNDEFINED;
|
||
}
|
||
scm_whash_insert (scm_source_whash,
|
||
obj,
|
||
scm_make_srcprops (line,
|
||
column,
|
||
filename,
|
||
copy,
|
||
SCM_EOL));
|
||
}
|
||
return obj;
|
||
}
|
||
}
|
||
|
||
/* Manipulate the read-hash-procedures alist. This could be written in
|
||
Scheme, but maybe it will also be used by C code during initialisation. */
|
||
SCM_DEFINE (scm_read_hash_extend, "read-hash-extend", 2, 0, 0,
|
||
(SCM chr, SCM proc),
|
||
"Install the procedure @var{proc} for reading expressions\n"
|
||
"starting with the character sequence @code{#} and @var{chr}.\n"
|
||
"@var{proc} will be called with two arguments: the character\n"
|
||
"@var{chr} and the port to read further data from. The object\n"
|
||
"returned will be the return value of @code{read}. \n"
|
||
"Passing @code{#f} for @var{proc} will remove a previous setting. \n"
|
||
)
|
||
#define FUNC_NAME s_scm_read_hash_extend
|
||
{
|
||
SCM this;
|
||
SCM prev;
|
||
|
||
SCM_VALIDATE_CHAR (1, chr);
|
||
SCM_ASSERT (scm_is_false (proc)
|
||
|| scm_is_eq (scm_procedure_p (proc), SCM_BOOL_T),
|
||
proc, SCM_ARG2, FUNC_NAME);
|
||
|
||
/* Check if chr is already in the alist. */
|
||
this = *scm_read_hash_procedures;
|
||
prev = SCM_BOOL_F;
|
||
while (1)
|
||
{
|
||
if (scm_is_null (this))
|
||
{
|
||
/* not found, so add it to the beginning. */
|
||
if (scm_is_true (proc))
|
||
{
|
||
*scm_read_hash_procedures =
|
||
scm_cons (scm_cons (chr, proc), *scm_read_hash_procedures);
|
||
}
|
||
break;
|
||
}
|
||
if (scm_is_eq (chr, SCM_CAAR (this)))
|
||
{
|
||
/* already in the alist. */
|
||
if (scm_is_false (proc))
|
||
{
|
||
/* remove it. */
|
||
if (scm_is_false (prev))
|
||
{
|
||
*scm_read_hash_procedures =
|
||
SCM_CDR (*scm_read_hash_procedures);
|
||
}
|
||
else
|
||
scm_set_cdr_x (prev, SCM_CDR (this));
|
||
}
|
||
else
|
||
{
|
||
/* replace it. */
|
||
scm_set_cdr_x (SCM_CAR (this), proc);
|
||
}
|
||
break;
|
||
}
|
||
prev = this;
|
||
this = SCM_CDR (this);
|
||
}
|
||
|
||
return SCM_UNSPECIFIED;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
/* Recover the read-hash procedure corresponding to char c. */
|
||
static SCM
|
||
scm_get_hash_procedure (int c)
|
||
{
|
||
SCM rest = *scm_read_hash_procedures;
|
||
|
||
while (1)
|
||
{
|
||
if (scm_is_null (rest))
|
||
return SCM_BOOL_F;
|
||
|
||
if (SCM_CHAR (SCM_CAAR (rest)) == c)
|
||
return SCM_CDAR (rest);
|
||
|
||
rest = SCM_CDR (rest);
|
||
}
|
||
}
|
||
|
||
#define SCM_ENCODING_SEARCH_SIZE (500)
|
||
|
||
/* Search the first few hundred characters of a file for an Emacs-like coding
|
||
declaration. Returns either NULL or a string whose storage has been
|
||
allocated with `scm_gc_malloc ()'. */
|
||
char *
|
||
scm_i_scan_for_encoding (SCM port)
|
||
{
|
||
char header[SCM_ENCODING_SEARCH_SIZE+1];
|
||
size_t bytes_read, encoding_length, i;
|
||
char *encoding = NULL;
|
||
int utf8_bom = 0;
|
||
char *pos, *encoding_start;
|
||
int in_comment;
|
||
|
||
if (SCM_FPORTP (port) && !SCM_FDES_RANDOM_P (SCM_FPORT_FDES (port)))
|
||
/* PORT is a non-seekable file port (e.g., as created by Bash when using
|
||
"guile <(echo '(display "hello")')") so bail out. */
|
||
return NULL;
|
||
|
||
bytes_read = scm_c_read (port, header, SCM_ENCODING_SEARCH_SIZE);
|
||
|
||
scm_seek (port, scm_from_int (0), scm_from_int (SEEK_SET));
|
||
|
||
if (bytes_read > 3
|
||
&& header[0] == '\xef' && header[1] == '\xbb' && header[2] == '\xbf')
|
||
utf8_bom = 1;
|
||
|
||
/* search past "coding[:=]" */
|
||
pos = header;
|
||
while (1)
|
||
{
|
||
if ((pos = strstr(pos, "coding")) == NULL)
|
||
return NULL;
|
||
|
||
pos += strlen("coding");
|
||
if (pos - header >= SCM_ENCODING_SEARCH_SIZE ||
|
||
(*pos == ':' || *pos == '='))
|
||
{
|
||
pos ++;
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* skip spaces */
|
||
while (pos - header <= SCM_ENCODING_SEARCH_SIZE &&
|
||
(*pos == ' ' || *pos == '\t'))
|
||
pos ++;
|
||
|
||
/* grab the next token */
|
||
encoding_start = pos;
|
||
i = 0;
|
||
while (encoding_start + i - header <= SCM_ENCODING_SEARCH_SIZE
|
||
&& encoding_start + i - header < bytes_read
|
||
&& (isalnum ((int) encoding_start[i])
|
||
|| strchr ("_-.:/,+=()", encoding_start[i]) != NULL))
|
||
i++;
|
||
|
||
encoding_length = i;
|
||
if (encoding_length == 0)
|
||
return NULL;
|
||
|
||
encoding = scm_gc_strndup (encoding_start, encoding_length, "encoding");
|
||
for (i = 0; i < encoding_length; i++)
|
||
encoding[i] = toupper ((int) encoding[i]);
|
||
|
||
/* push backwards to make sure we were in a comment */
|
||
in_comment = 0;
|
||
pos = encoding_start;
|
||
while (pos >= header)
|
||
{
|
||
if (*pos == '\n')
|
||
{
|
||
/* This wasn't in a semicolon comment. Check for a
|
||
hash-bang comment. */
|
||
char *beg = strstr (header, "#!");
|
||
char *end = strstr (header, "!#");
|
||
if (beg < encoding_start && encoding_start + encoding_length < end)
|
||
in_comment = 1;
|
||
break;
|
||
}
|
||
if (*pos == ';')
|
||
{
|
||
in_comment = 1;
|
||
break;
|
||
}
|
||
pos --;
|
||
}
|
||
if (!in_comment)
|
||
/* This wasn't in a comment */
|
||
return NULL;
|
||
|
||
if (utf8_bom && strcmp(encoding, "UTF-8"))
|
||
scm_misc_error (NULL,
|
||
"the port input declares the encoding ~s but is encoded as UTF-8",
|
||
scm_list_1 (scm_from_locale_string (encoding)));
|
||
|
||
return encoding;
|
||
}
|
||
|
||
SCM_DEFINE (scm_file_encoding, "file-encoding", 1, 0, 0,
|
||
(SCM port),
|
||
"Scans the port for an Emacs-like character coding declaration\n"
|
||
"near the top of the contents of a port with random-acessible contents.\n"
|
||
"The coding declaration is of the form\n"
|
||
"@code{coding: XXXXX} and must appear in a scheme comment.\n"
|
||
"\n"
|
||
"Returns a string containing the character encoding of the file\n"
|
||
"if a declaration was found, or @code{#f} otherwise.\n")
|
||
#define FUNC_NAME s_scm_file_encoding
|
||
{
|
||
char *enc;
|
||
SCM s_enc;
|
||
|
||
enc = scm_i_scan_for_encoding (port);
|
||
if (enc == NULL)
|
||
return SCM_BOOL_F;
|
||
else
|
||
{
|
||
s_enc = scm_from_locale_string (enc);
|
||
return s_enc;
|
||
}
|
||
|
||
return SCM_BOOL_F;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
void
|
||
scm_init_read ()
|
||
{
|
||
scm_read_hash_procedures =
|
||
SCM_VARIABLE_LOC (scm_c_define ("read-hash-procedures", SCM_EOL));
|
||
|
||
scm_init_opts (scm_read_options, scm_read_opts);
|
||
#include "libguile/read.x"
|
||
}
|
||
|
||
/*
|
||
Local Variables:
|
||
c-file-style: "gnu"
|
||
End:
|
||
*/
|