--- /dev/null
+/* Copyright (C) 1995,1996,1997,1998,2000,2001, 2003, 2004, 2006, 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 2.1 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
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "libguile/_scm.h"
+#include "libguile/chars.h"
+#include "libguile/eval.h"
+#include "libguile/hash.h"
+#include "libguile/smob.h"
+#include "libguile/variable.h"
+#include "libguile/alist.h"
+#include "libguile/fluids.h"
+#include "libguile/strings.h"
+#include "libguile/vectors.h"
+#include "libguile/hashtab.h"
+#include "libguile/weaks.h"
+#include "libguile/modules.h"
+#include "libguile/read.h"
+#include "libguile/srfi-13.h"
+
+#include "libguile/validate.h"
+#include "libguile/symbols.h"
+
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+
+\f
+
+static SCM symbols;
+
+#ifdef GUILE_DEBUG
+SCM_DEFINE (scm_sys_symbols, "%symbols", 0, 0, 0,
+ (),
+ "Return the system symbol obarray.")
+#define FUNC_NAME s_scm_sys_symbols
+{
+ return symbols;
+}
+#undef FUNC_NAME
+#endif
+
+\f
+
+/* {Symbols}
+ */
+
+/* In order to optimize reading speed, this function breaks part of
+ * the hashtable abstraction. The optimizations are:
+ *
+ * 1. The argument string can be compared directly to symbol objects
+ * without first creating an SCM string object. (This would have
+ * been necessary if we had used the hashtable API in hashtab.h.)
+ *
+ * 2. We can use the raw hash value stored in scm_i_symbol_hash (sym)
+ * to speed up lookup.
+ *
+ * Both optimizations might be possible without breaking the
+ * abstraction if the API in hashtab.c is improved.
+ */
+
+unsigned long
+scm_i_hash_symbol (SCM obj, unsigned long n, void *closure)
+{
+ return scm_i_symbol_hash (obj) % n;
+}
+
+static SCM
+lookup_interned_symbol (const char *name, size_t len,
+ unsigned long raw_hash)
+{
+ /* Try to find the symbol in the symbols table */
+ SCM l;
+ unsigned long hash = raw_hash % SCM_HASHTABLE_N_BUCKETS (symbols);
+
+ for (l = SCM_HASHTABLE_BUCKET (symbols, hash);
+ !scm_is_null (l);
+ l = SCM_CDR (l))
+ {
+ SCM sym = SCM_CAAR (l);
+ if (scm_i_symbol_hash (sym) == raw_hash
+ && scm_i_symbol_length (sym) == len)
+ {
+ const char *chrs = scm_i_symbol_chars (sym);
+ size_t i = len;
+
+ while (i != 0)
+ {
+ --i;
+ if (name[i] != chrs[i])
+ goto next_symbol;
+ }
+
+ return sym;
+ }
+ next_symbol:
+ ;
+ }
+
+ return SCM_BOOL_F;
+}
+
+/* Intern SYMBOL, an uninterned symbol. */
+static void
+intern_symbol (SCM symbol)
+{
+ SCM slot, cell;
+ unsigned long hash;
+
+ hash = scm_i_symbol_hash (symbol) % SCM_HASHTABLE_N_BUCKETS (symbols);
+ slot = SCM_HASHTABLE_BUCKET (symbols, hash);
+ cell = scm_cons (symbol, SCM_UNDEFINED);
+
+ SCM_SET_HASHTABLE_BUCKET (symbols, hash, scm_cons (cell, slot));
+ SCM_HASHTABLE_INCREMENT (symbols);
+
+ if (SCM_HASHTABLE_N_ITEMS (symbols) > SCM_HASHTABLE_UPPER (symbols))
+ scm_i_rehash (symbols, scm_i_hash_symbol, 0, "intern_symbol");
+}
+
+static SCM
+scm_i_c_mem2symbol (const char *name, size_t len)
+{
+ SCM symbol;
+ size_t raw_hash = scm_string_hash ((const unsigned char *) name, len);
+
+ symbol = lookup_interned_symbol (name, len, raw_hash);
+ if (scm_is_false (symbol))
+ {
+ /* The symbol was not found, create it. */
+ symbol = scm_i_c_make_symbol (name, len, 0, raw_hash,
+ scm_cons (SCM_BOOL_F, SCM_EOL));
+ intern_symbol (symbol);
+ }
+
+ return symbol;
+}
+
+static SCM
+scm_i_mem2symbol (SCM str)
+{
+ SCM symbol;
+ const char *name = scm_i_string_chars (str);
+ size_t len = scm_i_string_length (str);
+ size_t raw_hash = scm_string_hash ((const unsigned char *) name, len);
+
+ symbol = lookup_interned_symbol (name, len, raw_hash);
+ if (scm_is_false (symbol))
+ {
+ /* The symbol was not found, create it. */
+ symbol = scm_i_make_symbol (str, 0, raw_hash,
+ scm_cons (SCM_BOOL_F, SCM_EOL));
+ intern_symbol (symbol);
+ }
+
+ return symbol;
+}
+
+
+static SCM
+scm_i_mem2uninterned_symbol (SCM str)
+{
+ const char *name = scm_i_string_chars (str);
+ size_t len = scm_i_string_length (str);
+ size_t raw_hash = scm_string_hash ((const unsigned char *) name, len);
+
+ return scm_i_make_symbol (str, SCM_I_F_SYMBOL_UNINTERNED,
+ raw_hash, scm_cons (SCM_BOOL_F, SCM_EOL));
+}
+
+SCM_DEFINE (scm_symbol_p, "symbol?", 1, 0, 0,
+ (SCM obj),
+ "Return @code{#t} if @var{obj} is a symbol, otherwise return\n"
+ "@code{#f}.")
+#define FUNC_NAME s_scm_symbol_p
+{
+ return scm_from_bool (scm_is_symbol (obj));
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_symbol_interned_p, "symbol-interned?", 1, 0, 0,
+ (SCM symbol),
+ "Return @code{#t} if @var{symbol} is interned, otherwise return\n"
+ "@code{#f}.")
+#define FUNC_NAME s_scm_symbol_interned_p
+{
+ SCM_VALIDATE_SYMBOL (1, symbol);
+ return scm_from_bool (scm_i_symbol_is_interned (symbol));
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_make_symbol, "make-symbol", 1, 0, 0,
+ (SCM name),
+ "Return a new uninterned symbol with the name @var{name}. "
+ "The returned symbol is guaranteed to be unique and future "
+ "calls to @code{string->symbol} will not return it.")
+#define FUNC_NAME s_scm_make_symbol
+{
+ SCM_VALIDATE_STRING (1, name);
+ return scm_i_mem2uninterned_symbol (name);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_symbol_to_string, "symbol->string", 1, 0, 0,
+ (SCM s),
+ "Return the name of @var{symbol} as a string. If the symbol was\n"
+ "part of an object returned as the value of a literal expression\n"
+ "(section @pxref{Literal expressions,,,r5rs, The Revised^5\n"
+ "Report on Scheme}) or by a call to the @code{read} procedure,\n"
+ "and its name contains alphabetic characters, then the string\n"
+ "returned will contain characters in the implementation's\n"
+ "preferred standard case---some implementations will prefer\n"
+ "upper case, others lower case. If the symbol was returned by\n"
+ "@code{string->symbol}, the case of characters in the string\n"
+ "returned will be the same as the case in the string that was\n"
+ "passed to @code{string->symbol}. It is an error to apply\n"
+ "mutation procedures like @code{string-set!} to strings returned\n"
+ "by this procedure.\n"
+ "\n"
+ "The following examples assume that the implementation's\n"
+ "standard case is lower case:\n"
+ "\n"
+ "@lisp\n"
+ "(symbol->string 'flying-fish) @result{} \"flying-fish\"\n"
+ "(symbol->string 'Martin) @result{} \"martin\"\n"
+ "(symbol->string\n"
+ " (string->symbol \"Malvina\")) @result{} \"Malvina\"\n"
+ "@end lisp")
+#define FUNC_NAME s_scm_symbol_to_string
+{
+ SCM_VALIDATE_SYMBOL (1, s);
+ return scm_i_symbol_substring (s, 0, scm_i_symbol_length (s));
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_string_to_symbol, "string->symbol", 1, 0, 0,
+ (SCM string),
+ "Return the symbol whose name is @var{string}. This procedure\n"
+ "can create symbols with names containing special characters or\n"
+ "letters in the non-standard case, but it is usually a bad idea\n"
+ "to create such symbols because in some implementations of\n"
+ "Scheme they cannot be read as themselves. See\n"
+ "@code{symbol->string}.\n"
+ "\n"
+ "The following examples assume that the implementation's\n"
+ "standard case is lower case:\n"
+ "\n"
+ "@lisp\n"
+ "(eq? 'mISSISSIppi 'mississippi) @result{} #t\n"
+ "(string->symbol \"mISSISSIppi\") @result{} @r{the symbol with name \"mISSISSIppi\"}\n"
+ "(eq? 'bitBlt (string->symbol \"bitBlt\")) @result{} #f\n"
+ "(eq? 'JollyWog\n"
+ " (string->symbol (symbol->string 'JollyWog))) @result{} #t\n"
+ "(string=? \"K. Harper, M.D.\"\n"
+ " (symbol->string\n"
+ " (string->symbol \"K. Harper, M.D.\"))) @result{}#t\n"
+ "@end lisp")
+#define FUNC_NAME s_scm_string_to_symbol
+{
+ SCM_VALIDATE_STRING (1, string);
+ return scm_i_mem2symbol (string);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_string_ci_to_symbol, "string-ci->symbol", 1, 0, 0,
+ (SCM str),
+ "Return the symbol whose name is @var{str}. @var{str} is\n"
+ "converted to lowercase before the conversion is done, if Guile\n"
+ "is currently reading symbols case-insensitively.")
+#define FUNC_NAME s_scm_string_ci_to_symbol
+{
+ return scm_string_to_symbol (SCM_CASE_INSENSITIVE_P
+ ? scm_string_downcase(str)
+ : str);
+}
+#undef FUNC_NAME
+
+#define MAX_PREFIX_LENGTH 30
+
+SCM_DEFINE (scm_gensym, "gensym", 0, 1, 0,
+ (SCM prefix),
+ "Create a new symbol with a name constructed from a prefix and\n"
+ "a counter value. The string @var{prefix} can be specified as\n"
+ "an optional argument. Default prefix is @code{ g}. The counter\n"
+ "is increased by 1 at each call. There is no provision for\n"
+ "resetting the counter.")
+#define FUNC_NAME s_scm_gensym
+{
+ static int gensym_counter = 0;
+
+ SCM suffix, name;
+ int n, n_digits;
+ char buf[SCM_INTBUFLEN];
+
+ if (SCM_UNBNDP (prefix))
+ prefix = scm_from_locale_string (" g");
+
+ /* mutex in case another thread looks and incs at the exact same moment */
+ scm_i_scm_pthread_mutex_lock (&scm_i_misc_mutex);
+ n = gensym_counter++;
+ scm_i_pthread_mutex_unlock (&scm_i_misc_mutex);
+
+ n_digits = scm_iint2str (n, 10, buf);
+ suffix = scm_from_locale_stringn (buf, n_digits);
+ name = scm_string_append (scm_list_2 (prefix, suffix));
+ return scm_string_to_symbol (name);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_symbol_hash, "symbol-hash", 1, 0, 0,
+ (SCM symbol),
+ "Return a hash value for @var{symbol}.")
+#define FUNC_NAME s_scm_symbol_hash
+{
+ SCM_VALIDATE_SYMBOL (1, symbol);
+ return scm_from_ulong (scm_i_symbol_hash (symbol));
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_symbol_fref, "symbol-fref", 1, 0, 0,
+ (SCM s),
+ "Return the contents of @var{symbol}'s @dfn{function slot}.")
+#define FUNC_NAME s_scm_symbol_fref
+{
+ SCM_VALIDATE_SYMBOL (1, s);
+ return SCM_CAR (SCM_CELL_OBJECT_3 (s));
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_symbol_pref, "symbol-pref", 1, 0, 0,
+ (SCM s),
+ "Return the @dfn{property list} currently associated with @var{symbol}.")
+#define FUNC_NAME s_scm_symbol_pref
+{
+ SCM_VALIDATE_SYMBOL (1, s);
+ return SCM_CDR (SCM_CELL_OBJECT_3 (s));
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_symbol_fset_x, "symbol-fset!", 2, 0, 0,
+ (SCM s, SCM val),
+ "Change the binding of @var{symbol}'s function slot.")
+#define FUNC_NAME s_scm_symbol_fset_x
+{
+ SCM_VALIDATE_SYMBOL (1, s);
+ SCM_SETCAR (SCM_CELL_OBJECT_3 (s), val);
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_symbol_pset_x, "symbol-pset!", 2, 0, 0,
+ (SCM s, SCM val),
+ "Change the binding of @var{symbol}'s property slot.")
+#define FUNC_NAME s_scm_symbol_pset_x
+{
+ SCM_VALIDATE_SYMBOL (1, s);
+ SCM_SETCDR (SCM_CELL_OBJECT_3 (s), val);
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM
+scm_from_locale_symbol (const char *sym)
+{
+ return scm_i_c_mem2symbol (sym, strlen (sym));
+}
+
+SCM
+scm_from_locale_symboln (const char *sym, size_t len)
+{
+ return scm_i_c_mem2symbol (sym, len);
+}
+
+SCM
+scm_take_locale_symboln (char *sym, size_t len)
+{
+ SCM res;
+ unsigned long raw_hash;
+
+ if (len == (size_t)-1)
+ len = strlen (sym);
+ else
+ {
+ /* Ensure STR is null terminated. A realloc for 1 extra byte should
+ often be satisfied from the alignment padding after the block, with
+ no actual data movement. */
+ sym = scm_realloc (sym, len+1);
+ sym[len] = '\0';
+ }
+
+ raw_hash = scm_string_hash ((unsigned char *)sym, len);
+ res = lookup_interned_symbol (sym, len, raw_hash);
+ if (scm_is_false (res))
+ {
+ res = scm_i_c_take_symbol (sym, len, 0, raw_hash,
+ scm_cons (SCM_BOOL_F, SCM_EOL));
+ intern_symbol (res);
+ }
+ else
+ free (sym);
+
+ return res;
+}
+
+SCM
+scm_take_locale_symbol (char *sym)
+{
+ return scm_take_locale_symboln (sym, (size_t)-1);
+}
+
+void
+scm_symbols_prehistory ()
+{
+ symbols = scm_make_weak_key_hash_table (scm_from_int (2139));
+ scm_permanent_object (symbols);
+}
+
+
+void
+scm_init_symbols ()
+{
+#include "libguile/symbols.x"
+}
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/
projects / lilypond.git / blobdiff