--- /dev/null
+/* Copyright (C) 1997, 1998, 1999, 2000, 2001, 2004, 2006, 2007 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
+
+/* regex-posix.c -- POSIX regular expression support.
+
+ This code was written against Henry Spencer's famous regex package.
+ The principal reference for POSIX behavior was the man page for this
+ library, not the 1003.2 document itself. Ergo, other `POSIX'
+ libraries which do not agree with the Spencer implementation may
+ produce varying behavior. Sigh. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <sys/types.h>
+
+#include "libguile/_scm.h"
+
+/* Supposedly, this file is never compiled unless we know we have
+ POSIX regular expressions. But we still put this in an #ifdef so
+ the file is CPP'able (for dependency scanning) even on systems that
+ don't have a <regex.h> header. */
+#ifdef HAVE_REGCOMP
+#ifdef HAVE_REGEX_H
+#include <regex.h>
+#else
+#ifdef HAVE_RXPOSIX_H
+#include <rxposix.h> /* GNU Rx library */
+#else
+#ifdef HAVE_RX_RXPOSIX_H
+#include <rx/rxposix.h> /* GNU Rx library on Linux */
+#endif
+#endif
+#endif
+#endif
+
+#include "libguile/async.h"
+#include "libguile/smob.h"
+#include "libguile/symbols.h"
+#include "libguile/vectors.h"
+#include "libguile/strports.h"
+#include "libguile/ports.h"
+#include "libguile/feature.h"
+#include "libguile/strings.h"
+
+#include "libguile/validate.h"
+#include "libguile/regex-posix.h"
+
+/* This is defined by some regex libraries and omitted by others. */
+#ifndef REG_BASIC
+#define REG_BASIC 0
+#endif
+
+scm_t_bits scm_tc16_regex;
+
+static size_t
+regex_free (SCM obj)
+{
+ regfree (SCM_RGX (obj));
+ scm_gc_free (SCM_RGX (obj), sizeof(regex_t), "regex");
+ return 0;
+}
+
+\f
+
+SCM_SYMBOL (scm_regexp_error_key, "regular-expression-syntax");
+
+static SCM
+scm_regexp_error_msg (int regerrno, regex_t *rx)
+{
+ char *errmsg;
+ int l;
+
+ errmsg = scm_malloc (80);
+ l = regerror (regerrno, rx, errmsg, 80);
+ if (l > 80)
+ {
+ free (errmsg);
+ errmsg = scm_malloc (l);
+ regerror (regerrno, rx, errmsg, l);
+ }
+ return scm_take_locale_string (errmsg);
+}
+
+SCM_DEFINE (scm_regexp_p, "regexp?", 1, 0, 0,
+ (SCM obj),
+ "Return @code{#t} if @var{obj} is a compiled regular expression,\n"
+ "or @code{#f} otherwise.")
+#define FUNC_NAME s_scm_regexp_p
+{
+ return scm_from_bool(SCM_RGXP (obj));
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_make_regexp, "make-regexp", 1, 0, 1,
+ (SCM pat, SCM flags),
+ "Compile the regular expression described by @var{pat}, and\n"
+ "return the compiled regexp structure. If @var{pat} does not\n"
+ "describe a legal regular expression, @code{make-regexp} throws\n"
+ "a @code{regular-expression-syntax} error.\n"
+ "\n"
+ "The @var{flags} arguments change the behavior of the compiled\n"
+ "regular expression. The following flags may be supplied:\n"
+ "\n"
+ "@table @code\n"
+ "@item regexp/icase\n"
+ "Consider uppercase and lowercase letters to be the same when\n"
+ "matching.\n"
+ "@item regexp/newline\n"
+ "If a newline appears in the target string, then permit the\n"
+ "@samp{^} and @samp{$} operators to match immediately after or\n"
+ "immediately before the newline, respectively. Also, the\n"
+ "@samp{.} and @samp{[^...]} operators will never match a newline\n"
+ "character. The intent of this flag is to treat the target\n"
+ "string as a buffer containing many lines of text, and the\n"
+ "regular expression as a pattern that may match a single one of\n"
+ "those lines.\n"
+ "@item regexp/basic\n"
+ "Compile a basic (``obsolete'') regexp instead of the extended\n"
+ "(``modern'') regexps that are the default. Basic regexps do\n"
+ "not consider @samp{|}, @samp{+} or @samp{?} to be special\n"
+ "characters, and require the @samp{@{...@}} and @samp{(...)}\n"
+ "metacharacters to be backslash-escaped (@pxref{Backslash\n"
+ "Escapes}). There are several other differences between basic\n"
+ "and extended regular expressions, but these are the most\n"
+ "significant.\n"
+ "@item regexp/extended\n"
+ "Compile an extended regular expression rather than a basic\n"
+ "regexp. This is the default behavior; this flag will not\n"
+ "usually be needed. If a call to @code{make-regexp} includes\n"
+ "both @code{regexp/basic} and @code{regexp/extended} flags, the\n"
+ "one which comes last will override the earlier one.\n"
+ "@end table")
+#define FUNC_NAME s_scm_make_regexp
+{
+ SCM flag;
+ regex_t *rx;
+ int status, cflags;
+ char *c_pat;
+
+ SCM_VALIDATE_STRING (1, pat);
+ SCM_VALIDATE_REST_ARGUMENT (flags);
+
+ /* Examine list of regexp flags. If REG_BASIC is supplied, then
+ turn off REG_EXTENDED flag (on by default). */
+ cflags = REG_EXTENDED;
+ flag = flags;
+ while (!scm_is_null (flag))
+ {
+ if (scm_to_int (SCM_CAR (flag)) == REG_BASIC)
+ cflags &= ~REG_EXTENDED;
+ else
+ cflags |= scm_to_int (SCM_CAR (flag));
+ flag = SCM_CDR (flag);
+ }
+
+ rx = scm_gc_malloc (sizeof(regex_t), "regex");
+ c_pat = scm_to_locale_string (pat);
+ status = regcomp (rx, c_pat,
+ /* Make sure they're not passing REG_NOSUB;
+ regexp-exec assumes we're getting match data. */
+ cflags & ~REG_NOSUB);
+ free (c_pat);
+ if (status != 0)
+ {
+ SCM errmsg = scm_regexp_error_msg (status, rx);
+ scm_gc_free (rx, sizeof(regex_t), "regex");
+ scm_error_scm (scm_regexp_error_key,
+ scm_from_locale_string (FUNC_NAME),
+ errmsg,
+ SCM_BOOL_F,
+ scm_list_1 (pat));
+
+ /* never returns */
+ }
+ SCM_RETURN_NEWSMOB (scm_tc16_regex, rx);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_regexp_exec, "regexp-exec", 2, 2, 0,
+ (SCM rx, SCM str, SCM start, SCM flags),
+ "Match the compiled regular expression @var{rx} against\n"
+ "@code{str}. If the optional integer @var{start} argument is\n"
+ "provided, begin matching from that position in the string.\n"
+ "Return a match structure describing the results of the match,\n"
+ "or @code{#f} if no match could be found.\n"
+ "\n"
+ "The @var{flags} arguments change the matching behavior.\n"
+ "The following flags may be supplied:\n"
+ "\n"
+ "@table @code\n"
+ "@item regexp/notbol\n"
+ "Operator @samp{^} always fails (unless @code{regexp/newline}\n"
+ "is used). Use this when the beginning of the string should\n"
+ "not be considered the beginning of a line.\n"
+ "@item regexp/noteol\n"
+ "Operator @samp{$} always fails (unless @code{regexp/newline}\n"
+ "is used). Use this when the end of the string should not be\n"
+ "considered the end of a line.\n"
+ "@end table")
+#define FUNC_NAME s_scm_regexp_exec
+{
+ /* We used to have an SCM_DEFER_INTS, and then later an
+ SCM_CRITICAL_SECTION_START, around the regexec() call. Can't quite
+ remember what defer ints was for, but a critical section would only be
+ wanted now if we think regexec() is not thread-safe. The posix spec
+
+ http://www.opengroup.org/onlinepubs/009695399/functions/regcomp.html
+
+ reads like regexec is meant to be both thread safe and reentrant
+ (mentioning simultaneous use in threads, and in signal handlers). So
+ for now believe no protection needed. */
+
+ int status, nmatches, offset;
+ regmatch_t *matches;
+ char *c_str;
+ SCM mvec = SCM_BOOL_F;
+ SCM substr;
+
+ SCM_VALIDATE_RGXP (1, rx);
+ SCM_VALIDATE_STRING (2, str);
+
+ if (SCM_UNBNDP (start))
+ {
+ substr = str;
+ offset = 0;
+ }
+ else
+ {
+ substr = scm_substring (str, start, SCM_UNDEFINED);
+ offset = scm_to_int (start);
+ }
+
+ if (SCM_UNBNDP (flags))
+ flags = SCM_INUM0;
+
+ /* re_nsub doesn't account for the `subexpression' representing the
+ whole regexp, so add 1 to nmatches. */
+
+ nmatches = SCM_RGX(rx)->re_nsub + 1;
+ matches = scm_malloc (sizeof (regmatch_t) * nmatches);
+ c_str = scm_to_locale_string (substr);
+ status = regexec (SCM_RGX (rx), c_str, nmatches, matches,
+ scm_to_int (flags));
+ free (c_str);
+
+ if (!status)
+ {
+ int i;
+ /* The match vector must include a cell for the string that was matched,
+ so add 1. */
+ mvec = scm_c_make_vector (nmatches + 1, SCM_UNSPECIFIED);
+ SCM_SIMPLE_VECTOR_SET(mvec,0, str);
+ for (i = 0; i < nmatches; ++i)
+ if (matches[i].rm_so == -1)
+ SCM_SIMPLE_VECTOR_SET(mvec, i+1,
+ scm_cons (scm_from_int (-1), scm_from_int (-1)));
+ else
+ SCM_SIMPLE_VECTOR_SET(mvec, i+1,
+ scm_cons (scm_from_long (matches[i].rm_so + offset),
+ scm_from_long (matches[i].rm_eo + offset)));
+ }
+ free (matches);
+
+ if (status != 0 && status != REG_NOMATCH)
+ scm_error_scm (scm_regexp_error_key,
+ scm_from_locale_string (FUNC_NAME),
+ scm_regexp_error_msg (status, SCM_RGX (rx)),
+ SCM_BOOL_F, SCM_BOOL_F);
+ return mvec;
+}
+#undef FUNC_NAME
+
+void
+scm_init_regex_posix ()
+{
+ scm_tc16_regex = scm_make_smob_type ("regexp", sizeof (regex_t));
+ scm_set_smob_free (scm_tc16_regex, regex_free);
+
+ /* Compilation flags. */
+ scm_c_define ("regexp/basic", scm_from_int (REG_BASIC));
+ scm_c_define ("regexp/extended", scm_from_int (REG_EXTENDED));
+ scm_c_define ("regexp/icase", scm_from_int (REG_ICASE));
+ scm_c_define ("regexp/newline", scm_from_int (REG_NEWLINE));
+
+ /* Execution flags. */
+ scm_c_define ("regexp/notbol", scm_from_int (REG_NOTBOL));
+ scm_c_define ("regexp/noteol", scm_from_int (REG_NOTEOL));
+
+#include "libguile/regex-posix.x"
+
+ scm_add_feature ("regex");
+}
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/
projects / lilypond.git / blobdiff