-/* classes: h_files */
-
-#ifndef SCM_STRINGS_H
-#define SCM_STRINGS_H
-
-/* Copyright (C) 1995,1996,1997,1998,2000,2001 Free Software Foundation, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this software; see the file COPYING. If not, write to
- * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307 USA
- *
- * As a special exception, the Free Software Foundation gives permission
- * for additional uses of the text contained in its release of GUILE.
- *
- * The exception is that, if you link the GUILE library with other files
- * to produce an executable, this does not by itself cause the
- * resulting executable to be covered by the GNU General Public License.
- * Your use of that executable is in no way restricted on account of
- * linking the GUILE library code into it.
- *
- * This exception does not however invalidate any other reasons why
- * the executable file might be covered by the GNU General Public License.
- *
- * This exception applies only to the code released by the
- * Free Software Foundation under the name GUILE. If you copy
- * code from other Free Software Foundation releases into a copy of
- * GUILE, as the General Public License permits, the exception does
- * not apply to the code that you add in this way. To avoid misleading
- * anyone as to the status of such modified files, you must delete
- * this exception notice from them.
- *
- * If you write modifications of your own for GUILE, it is your choice
- * whether to permit this exception to apply to your modifications.
- * If you do not wish that, delete this exception notice. */
-
-\f
-
-#include "libguile/__scm.h"
-
-\f
-
-#define SCM_STRINGP(x) (!SCM_IMP (x) && (SCM_TYP7 (x) == scm_tc7_string))
-#define SCM_STRING_UCHARS(x) ((unsigned char *) (SCM_CELL_WORD_1 (x)))
-#define SCM_STRING_CHARS(x) ((char *) (SCM_CELL_WORD_1 (x)))
-#define SCM_SET_STRING_CHARS(s, c) (SCM_SET_CELL_WORD_1 ((s), (c)))
-#define SCM_STRING_MAX_LENGTH ((1UL << 24) - 1UL)
-#define SCM_STRING_LENGTH(x) ((size_t) (SCM_CELL_WORD_0 (x) >> 8))
-#define SCM_SET_STRING_LENGTH(s, l) (SCM_SET_CELL_WORD_0 ((s), ((l) << 8) + scm_tc7_string))
-
-\f
-
-extern SCM scm_string_p (SCM x);
-extern SCM scm_string (SCM chrs);
-extern SCM scm_makfromstrs (int argc, char **argv);
-extern SCM scm_take_str (char *s, size_t len);
-extern SCM scm_take0str (char *s);
-extern SCM scm_mem2string (const char *src, size_t len);
-extern SCM scm_makfrom0str (const char *src);
-extern SCM scm_makfrom0str_opt (const char *src);
-extern SCM scm_allocate_string (size_t len);
-extern SCM scm_make_string (SCM k, SCM chr);
-extern SCM scm_string_length (SCM str);
-extern SCM scm_string_ref (SCM str, SCM k);
-extern SCM scm_string_set_x (SCM str, SCM k, SCM chr);
-extern SCM scm_substring (SCM str, SCM start, SCM end);
-extern SCM scm_string_append (SCM args);
-extern void scm_init_strings (void);
-
-\f
-
-#if (SCM_ENABLE_DEPRECATED == 1)
-
-#define SCM_STRING_COERCE_0TERMINATION_X(x) (x)
-
-#endif
-
-#endif /* SCM_STRINGS_H */
-
-/*
- Local Variables:
- c-file-style: "gnu"
- End:
-*/
+/* classes: h_files */
+
+#ifndef SCM_STRINGS_H
+#define SCM_STRINGS_H
+
+/* Copyright (C) 1995,1996,1997,1998,2000,2001, 2004, 2005, 2006, 2008, 2009 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
+ */
+
+\f
+
+#include "libguile/__scm.h"
+
+\f
+
+/* String representation.
+
+ A string is a piece of a stringbuf. A stringbuf can be used by
+ more than one string. When a string is written to and the
+ stringbuf of that string is used by more than one string, a new
+ stringbuf is created. That is, strings are copy-on-write. This
+ behavior can be used to make the substring operation quite
+ efficient.
+
+ The implementation is tuned so that mutating a string is costly,
+ but just reading it is cheap and lock-free.
+
+ There are also mutation-sharing strings. They refer to a part of
+ an ordinary string. Writing to a mutation-sharing string just
+ writes to the ordinary string.
+
+
+ Internal, low level interface to the character arrays
+
+ - Use scm_is_narrow_string to determine is the string is narrow or
+ wide.
+
+ - Use scm_i_string_chars or scm_i_string_wide_chars to get a
+ pointer to the byte or scm_t_wchar array of a string for reading.
+ Use scm_i_string_length to get the number of characters in that
+ array. The array is not null-terminated.
+
+ - The array is valid as long as the corresponding SCM object is
+ protected but only until the next SCM_TICK. During such a 'safe
+ point', strings might change their representation.
+
+ - Use scm_i_string_start_writing to get a version of the string
+ ready for reading and writing. This is a potentially costly
+ operation since it implements the copy-on-write behavior. When
+ done with the writing, call scm_i_string_stop_writing. You must
+ do this before the next SCM_TICK. (This means, before calling
+ almost any other scm_ function and you can't allow throws, of
+ course.)
+
+ - New strings can be created with scm_i_make_string or
+ scm_i_make_wide_string. This gives access to a writable pointer
+ that remains valid as long as nobody else makes a copy-on-write
+ substring of the string. Do not call scm_i_string_stop_writing
+ for this pointer.
+
+ - Alternately, scm_i_string_ref and scm_i_string_set_x can be used
+ to read and write strings without worrying about whether the
+ string is narrow or wide. scm_i_string_set_x still needs to be
+ bracketed by scm_i_string_start_writing and
+ scm_i_string_stop_writing.
+
+ Legacy interface
+
+ - SCM_STRINGP is just scm_is_string.
+
+ - SCM_STRING_CHARS uses scm_i_string_writable_chars and immediately
+ calls scm_i_stop_writing, hoping for the best. SCM_STRING_LENGTH
+ is the same as scm_i_string_length. SCM_STRING_CHARS will throw
+ an error for for strings that are not null-terminated. There is
+ no wide version of this interface.
+*/
+
+/* A type indicating what strategy to take when string locale
+ conversion is unsuccessful. */
+typedef enum
+{
+ SCM_FAILED_CONVERSION_ERROR = SCM_ICONVEH_ERROR,
+ SCM_FAILED_CONVERSION_QUESTION_MARK = SCM_ICONVEH_QUESTION_MARK,
+ SCM_FAILED_CONVERSION_ESCAPE_SEQUENCE = SCM_ICONVEH_ESCAPE_SEQUENCE
+} scm_t_string_failed_conversion_handler;
+
+SCM_INTERNAL SCM scm_nullstr;
+
+SCM_API SCM scm_string_p (SCM x);
+SCM_API SCM scm_string (SCM chrs);
+SCM_API SCM scm_make_string (SCM k, SCM chr);
+SCM_API SCM scm_string_length (SCM str);
+SCM_API SCM scm_string_bytes_per_char (SCM str);
+SCM_API SCM scm_string_ref (SCM str, SCM k);
+SCM_API SCM scm_string_set_x (SCM str, SCM k, SCM chr);
+SCM_API SCM scm_substring (SCM str, SCM start, SCM end);
+SCM_API SCM scm_substring_read_only (SCM str, SCM start, SCM end);
+SCM_API SCM scm_substring_shared (SCM str, SCM start, SCM end);
+SCM_API SCM scm_substring_copy (SCM str, SCM start, SCM end);
+SCM_API SCM scm_string_append (SCM args);
+
+SCM_API SCM scm_from_stringn (const char *str, size_t len,
+ const char *encoding,
+ scm_t_string_failed_conversion_handler
+ handler);
+SCM_API SCM scm_c_make_string (size_t len, SCM chr);
+SCM_API size_t scm_c_string_length (SCM str);
+SCM_API size_t scm_c_symbol_length (SCM sym);
+SCM_API SCM scm_c_string_ref (SCM str, size_t pos);
+SCM_API void scm_c_string_set_x (SCM str, size_t pos, SCM chr);
+SCM_API SCM scm_c_substring (SCM str, size_t start, size_t end);
+SCM_API SCM scm_c_substring_read_only (SCM str, size_t start, size_t end);
+SCM_API SCM scm_c_substring_shared (SCM str, size_t start, size_t end);
+SCM_API SCM scm_c_substring_copy (SCM str, size_t start, size_t end);
+
+SCM_API int scm_is_string (SCM x);
+SCM_API SCM scm_from_locale_string (const char *str);
+SCM_API SCM scm_from_locale_stringn (const char *str, size_t len);
+SCM_INTERNAL SCM scm_i_from_utf8_string (const scm_t_uint8 *str);
+SCM_API SCM scm_take_locale_string (char *str);
+SCM_API SCM scm_take_locale_stringn (char *str, size_t len);
+SCM_API char *scm_to_locale_string (SCM str);
+SCM_API char *scm_to_locale_stringn (SCM str, size_t *lenp);
+SCM_INTERNAL char *scm_to_stringn (SCM str, size_t *lenp,
+ const char *encoding,
+ scm_t_string_failed_conversion_handler
+ handler);
+SCM_INTERNAL scm_t_uint8 *scm_i_to_utf8_string (SCM str);
+SCM_API size_t scm_to_locale_stringbuf (SCM str, char *buf, size_t max_len);
+
+SCM_API SCM scm_makfromstrs (int argc, char **argv);
+
+\f
+/* internal constants */
+
+/* Type tag for read-only strings. */
+#define scm_tc7_ro_string (scm_tc7_string + 0x200)
+
+/* Flags for shared and wide strings. */
+#define SCM_I_STRINGBUF_F_SHARED 0x100
+#define SCM_I_STRINGBUF_F_WIDE 0x400
+
+
+/* internal accessor functions. Arguments must be valid. */
+
+SCM_INTERNAL SCM scm_i_make_string (size_t len, char **datap);
+SCM_INTERNAL SCM scm_i_make_wide_string (size_t len, scm_t_wchar **datap);
+SCM_INTERNAL SCM scm_i_substring (SCM str, size_t start, size_t end);
+SCM_INTERNAL SCM scm_i_substring_read_only (SCM str, size_t start, size_t end);
+SCM_INTERNAL SCM scm_i_substring_shared (SCM str, size_t start, size_t end);
+SCM_INTERNAL SCM scm_i_substring_copy (SCM str, size_t start, size_t end);
+SCM_INTERNAL size_t scm_i_string_length (SCM str);
+SCM_API /* FIXME: not internal */ const char *scm_i_string_chars (SCM str);
+SCM_API /* FIXME: not internal */ char *scm_i_string_writable_chars (SCM str);
+SCM_INTERNAL const scm_t_wchar *scm_i_string_wide_chars (SCM str);
+SCM_INTERNAL SCM scm_i_string_start_writing (SCM str);
+SCM_INTERNAL void scm_i_string_stop_writing (void);
+SCM_INTERNAL int scm_i_is_narrow_string (SCM str);
+SCM_INTERNAL scm_t_wchar scm_i_string_ref (SCM str, size_t x);
+SCM_INTERNAL int scm_i_string_contains_char (SCM str, char c);
+SCM_INTERNAL int scm_i_string_strcmp (SCM sstr, size_t start_x, const char *cstr);
+SCM_INTERNAL void scm_i_string_set_x (SCM str, size_t p, scm_t_wchar chr);
+/* internal functions related to symbols. */
+
+SCM_INTERNAL SCM scm_i_make_symbol (SCM name, scm_t_bits flags,
+ unsigned long hash, SCM props);
+SCM_INTERNAL SCM
+scm_i_c_make_symbol (const char *name, size_t len,
+ scm_t_bits flags, unsigned long hash, SCM props);
+SCM_INTERNAL const char *scm_i_symbol_chars (SCM sym);
+SCM_INTERNAL const scm_t_wchar *scm_i_symbol_wide_chars (SCM sym);
+SCM_INTERNAL size_t scm_i_symbol_length (SCM sym);
+SCM_INTERNAL int scm_i_is_narrow_symbol (SCM str);
+SCM_INTERNAL int scm_i_try_narrow_string (SCM str);
+SCM_INTERNAL SCM scm_i_symbol_substring (SCM sym, size_t start, size_t end);
+SCM_INTERNAL scm_t_wchar scm_i_symbol_ref (SCM sym, size_t x);
+
+/* internal utility functions. */
+
+SCM_INTERNAL char **scm_i_allocate_string_pointers (SCM list);
+SCM_INTERNAL void scm_i_get_substring_spec (size_t len,
+ SCM start, size_t *cstart,
+ SCM end, size_t *cend);
+
+/* Debugging functions */
+
+SCM_API SCM scm_sys_string_dump (SCM);
+SCM_API SCM scm_sys_symbol_dump (SCM);
+#ifdef SCM_STRING_LENGTH_HISTOGRAM
+SCM_API SCM scm_sys_stringbuf_hist (void);
+#endif
+
+/* deprecated stuff */
+
+#if SCM_ENABLE_DEPRECATED
+
+SCM_DEPRECATED int scm_i_deprecated_stringp (SCM obj);
+SCM_DEPRECATED char *scm_i_deprecated_string_chars (SCM str);
+SCM_DEPRECATED size_t scm_i_deprecated_string_length (SCM str);
+
+#define SCM_STRINGP(x) scm_i_deprecated_stringp(x)
+#define SCM_STRING_CHARS(x) scm_i_deprecated_string_chars(x)
+#define SCM_STRING_LENGTH(x) scm_i_deprecated_string_length(x)
+#define SCM_STRING_UCHARS(str) ((unsigned char *)SCM_STRING_CHARS (str))
+
+#endif
+
+SCM_INTERNAL void scm_init_strings (void);
+
+#endif /* SCM_STRINGS_H */
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/