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rx.c：源码内容

This file is part of the librx library.
Librx is free software; you can redistribute it and/or modify it under
the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
Librx 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 Library General Public
License along with this software; see the file COPYING.LIB. If not,
write to the Free Software Foundation, 675 Mass Ave, Cambridge, MA
02139, USA. */
/* NOTE!!! AIX is so losing it requires this to be the first thing in the
* file.
* Do not put ANYTHING before it!
*/
#if !defined (__GNUC__) && defined (_AIX)
#pragma alloca
#endif
char rx_version_string[] = "GNU Rx version 0.06";
/* ``Too hard!''
* -- anon.
*/
#include <stdio.h>
#include <ctype.h>
#ifndef isgraph
#define isgraph(c) (isprint (c) && !isspace (c))
#endif
#ifndef isblank
#define isblank(c) ((c) == ' ' || (c) == 't')
#endif
#include <sys/types.h>
#undef MAX
#undef MIN
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))
typedef char boolean;
#define false 0
#define true 1
#ifndef RX_DECL
#define RX_DECL static
#endif
#ifndef __GCC__
#undef __inline__
#define __inline__
#endif
/* Emacs already defines alloca, sometimes. */
#ifndef alloca
/* Make alloca work the best possible way. */
#ifdef __GNUC__
#define alloca __builtin_alloca
#else /* not __GNUC__ */
#if HAVE_ALLOCA_H
#include <alloca.h>
#else /* not __GNUC__ or HAVE_ALLOCA_H */
#ifndef _AIX /* Already did AIX, up at the top. */
char *alloca ();
#endif /* not _AIX */
#endif /* not HAVE_ALLOCA_H */
#endif /* not __GNUC__ */
#endif /* not alloca */
/* Memory management and stuff for emacs. */
#define CHARBITS 8
#define remalloc(M, S) (M ? realloc (M, S) : malloc (S))
/* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
* use `alloca' instead of `malloc' for the backtracking stack.
*
* Emacs will die miserably if we don't do this.
*/
#ifdef REGEX_MALLOC
#define REGEX_ALLOCATE malloc
#else /* not REGEX_MALLOC */
#define REGEX_ALLOCATE alloca
#endif /* not REGEX_MALLOC */
#ifdef RX_WANT_RX_DEFS
#define RX_DECL extern
#define RX_DEF_QUAL
#else
#define RX_WANT_RX_DEFS
#define RX_DECL static
#define RX_DEF_QUAL static
#endif
#include "rx.h"
#undef RX_DECL
#define RX_DECL RX_DEF_QUAL
#ifndef emacs
#ifdef SYNTAX_TABLE
extern char *re_syntax_table;
#else /* not SYNTAX_TABLE */
/* RX_DECL char re_syntax_table[CHAR_SET_SIZE]; */
#ifdef __STDC__
static void
init_syntax_once (void)
#else
static void
init_syntax_once ()
#endif
{
register int c;
static int done = 0;
if (done)
return;
bzero (re_syntax_table, sizeof re_syntax_table);
for (c = 'a'; c <= 'z'; c++)
re_syntax_table[c] = Sword;
for (c = 'A'; c <= 'Z'; c++)
re_syntax_table[c] = Sword;
for (c = '0'; c <= '9'; c++)
re_syntax_table[c] = Sword;
re_syntax_table['_'] = Sword;
done = 1;
}
#endif /* not SYNTAX_TABLE */
#endif /* not emacs */
/* Compile with `-DRX_DEBUG' and use the following flags.
*
* Debugging flags:
* rx_debug - print information as a regexp is compiled
* rx_debug_trace - print information as a regexp is executed
*/
#ifdef RX_DEBUG
int rx_debug_compile = 0;
int rx_debug_trace = 0;
static struct re_pattern_buffer * dbug_rxb = 0;
#ifdef __STDC__
typedef void (*side_effect_printer) (struct rx *, void *, FILE *);
#else
typedef void (*side_effect_printer) ();
#endif
#ifdef __STDC__
static void print_cset (struct rx *rx, rx_Bitset cset, FILE * fp);
#else
static void print_cset ();
#endif
#ifdef __STDC__
static void
print_rexp (struct rx *rx,
struct rexp_node *node, int depth,
side_effect_printer seprint, FILE * fp)
#else
static void
print_rexp (rx, node, depth, seprint, fp)
struct rx *rx;
struct rexp_node *node;
int depth;
side_effect_printer seprint;
FILE * fp;
#endif
{
if (!node)
return;
else
{
switch (node->type)
{
case r_cset:
{
fprintf (fp, "%*s", depth, "");
print_cset (rx, node->params.cset, fp);
fputc ('n', fp);
break;
}
case r_opt:
case r_star:
fprintf (fp, "%*s%sn", depth, "",
node->type == r_opt ? "opt" : "star");
print_rexp (rx, node->params.pair.left, depth + 3, seprint, fp);
break;
case r_2phase_star:
fprintf (fp, "%*s2phase starn", depth, "");
print_rexp (rx, node->params.pair.right, depth + 3, seprint, fp);
print_rexp (rx, node->params.pair.left, depth + 3, seprint, fp);
break;
case r_alternate:
case r_concat:
fprintf (fp, "%*s%sn", depth, "",
node->type == r_alternate ? "alt" : "concat");
print_rexp (rx, node->params.pair.left, depth + 3, seprint, fp);
print_rexp (rx, node->params.pair.right, depth + 3, seprint, fp);
break;
case r_side_effect:
fprintf (fp, "%*sSide effect: ", depth, "");
seprint (rx, node->params.side_effect, fp);
fputc ('n', fp);
}
}
}
#ifdef __STDC__
static void
print_nfa (struct rx * rx,
struct rx_nfa_state * n,
side_effect_printer seprint, FILE * fp)
#else
static void
print_nfa (rx, n, seprint, fp)
struct rx * rx;
struct rx_nfa_state * n;
side_effect_printer seprint;
FILE * fp;
#endif
{
while (n)
{
struct rx_nfa_edge *e = n->edges;
struct rx_possible_future *ec = n->futures;
fprintf (fp, "node %d %sn", n->id,
n->is_final ? "final" : (n->is_start ? "start" : ""));
while (e)
{
fprintf (fp, " edge to %d, ", e->dest->id);
switch (e->type)
{
case ne_epsilon:
fprintf (fp, "epsilonn");
break;
case ne_side_effect:
fprintf (fp, "side effect ");
seprint (rx, e->params.side_effect, fp);
fputc ('n', fp);
break;
case ne_cset:
fprintf (fp, "cset ");
print_cset (rx, e->params.cset, fp);
fputc ('n', fp);
break;
}
e = e->next;
}
while (ec)
{
int x;
struct rx_nfa_state_set * s;
struct rx_se_list * l;
fprintf (fp, " eclosure to {");
for (s = ec->destset; s; s = s->cdr)
fprintf (fp, "%d ", s->car->id);
fprintf (fp, "} (");
for (l = ec->effects; l; l = l->cdr)
{
seprint (rx, l->car, fp);
fputc (' ', fp);
}
fprintf (fp, ")n");
ec = ec->next;
}
n = n->next;
}
}
static char * efnames [] =
{
"bogon",
"re_se_try",
"re_se_pushback",
"re_se_push0",
"re_se_pushpos",
"re_se_chkpos",
"re_se_poppos",
"re_se_at_dot",
"re_se_syntax",
"re_se_not_syntax",
"re_se_begbuf",
"re_se_hat",
"re_se_wordbeg",
"re_se_wordbound",
"re_se_notwordbound",
"re_se_wordend",
"re_se_endbuf",
"re_se_dollar",
"re_se_fail",
};
static char * efnames2[] =
{
"re_se_win",
"re_se_lparen",
"re_se_rparen",
"re_se_backref",
"re_se_iter",
"re_se_end_iter",
"re_se_tv"
};
static char * inx_names[] =
{
"rx_backtrack_point",
"rx_do_side_effects",
"rx_cache_miss",
"rx_next_char",
"rx_backtrack",
"rx_error_inx",
"rx_num_instructions"
};
#ifdef __STDC__
static void
re_seprint (struct rx * rx, void * effect, FILE * fp)
#else
static void
re_seprint (rx, effect, fp)
struct rx * rx;
void * effect;
FILE * fp;
#endif
{
if ((int)effect < 0)
fputs (efnames[-(int)effect], fp);
else if (dbug_rxb)
{
struct re_se_params * p = &dbug_rxb->se_params[(int)effect];
fprintf (fp, "%s(%d,%d)", efnames2[p->se], p->op1, p->op2);
}
else
fprintf (fp, "[complex op # %d]", (int)effect);
}
/* These are so the regex.c regression tests will compile. */
void
print_compiled_pattern (rxb)
struct re_pattern_buffer * rxb;
{
}
void
print_fastmap (fm)
char * fm;
{
}
#endif /* RX_DEBUG */
/* This page: Bitsets. Completely unintersting. */
#ifdef __STDC__
RX_DECL int
rx_bitset_is_equal (int size, rx_Bitset a, rx_Bitset b)
#else
RX_DECL int
rx_bitset_is_equal (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x;
RX_subset s = b[0];
b[0] = ~a[0];
for (x = rx_bitset_numb_subsets(size) - 1; a[x] == b[x]; --x)
;
b[0] = s;
return !x && s == a[0];
}
#ifdef __STDC__
RX_DECL int
rx_bitset_is_subset (int size, rx_Bitset a, rx_Bitset b)
#else
RX_DECL int
rx_bitset_is_subset (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x = rx_bitset_numb_subsets(size) - 1;
while (x-- && (a[x] & b[x]) == a[x]);
return x == -1;
}
#ifdef __STDC__
RX_DECL int
rx_bitset_empty (int size, rx_Bitset set)
#else
RX_DECL int
rx_bitset_empty (size, set)
int size;
rx_Bitset set;
#endif
{
int x;
RX_subset s = set[0];
set[0] = 1;
for (x = rx_bitset_numb_subsets(size) - 1; !set[x]; --x)
;
set[0] = s;
return !s;
}
#ifdef __STDC__
RX_DECL void
rx_bitset_null (int size, rx_Bitset b)
#else
RX_DECL void
rx_bitset_null (size, b)
int size;
rx_Bitset b;
#endif
{
bzero (b, rx_sizeof_bitset(size));
}
#ifdef __STDC__
RX_DECL void
rx_bitset_universe (int size, rx_Bitset b)
#else
RX_DECL void
rx_bitset_universe (size, b)
int size;
rx_Bitset b;
#endif
{
int x = rx_bitset_numb_subsets (size);
while (x--)
*b++ = ~(RX_subset)0;
}
#ifdef __STDC__
RX_DECL void
rx_bitset_complement (int size, rx_Bitset b)
#else
RX_DECL void
rx_bitset_complement (size, b)
int size;
rx_Bitset b;
#endif
{
int x = rx_bitset_numb_subsets (size);
while (x--)
{
*b = ~*b;
++b;
}
}
#ifdef __STDC__
RX_DECL void
rx_bitset_assign (int size, rx_Bitset a, rx_Bitset b)
#else
RX_DECL void
rx_bitset_assign (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x;
for (x = rx_bitset_numb_subsets(size) - 1; x >=0; --x)
a[x] = b[x];
}
#ifdef __STDC__
RX_DECL void
rx_bitset_union (int size, rx_Bitset a, rx_Bitset b)
#else
RX_DECL void
rx_bitset_union (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x;
for (x = rx_bitset_numb_subsets(size) - 1; x >=0; --x)
a[x] |= b[x];
}
#ifdef __STDC__
RX_DECL void
rx_bitset_intersection (int size,
rx_Bitset a, rx_Bitset b)
#else
RX_DECL void
rx_bitset_intersection (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x;
for (x = rx_bitset_numb_subsets(size) - 1; x >=0; --x)
a[x] &= b[x];
}
#ifdef __STDC__
RX_DECL void
rx_bitset_difference (int size, rx_Bitset a, rx_Bitset b)
#else
RX_DECL void
rx_bitset_difference (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x;
for (x = rx_bitset_numb_subsets(size) - 1; x >=0; --x)
a[x] &= ~ b[x];
}
#ifdef __STDC__
RX_DECL void
rx_bitset_revdifference (int size,
rx_Bitset a, rx_Bitset b)
#else
RX_DECL void
rx_bitset_revdifference (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x;
for (x = rx_bitset_numb_subsets(size) - 1; x >=0; --x)
a[x] = ~a[x] & b[x];
}
#ifdef __STDC__
RX_DECL void
rx_bitset_xor (int size, rx_Bitset a, rx_Bitset b)
#else
RX_DECL void
rx_bitset_xor (size, a, b)
int size;
rx_Bitset a;
rx_Bitset b;
#endif
{
int x;
for (x = rx_bitset_numb_subsets(size) - 1; x >=0; --x)
a[x] ^= b[x];
}
#ifdef __STDC__
RX_DECL unsigned long
rx_bitset_hash (int size, rx_Bitset b)
#else
RX_DECL unsigned long
rx_bitset_hash (size, b)
int size;
rx_Bitset b;
#endif
{
int x;
unsigned long hash = (unsigned long)rx_bitset_hash;
for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
hash ^= rx_bitset_subset_val(b, x);
return hash;
}
RX_DECL RX_subset rx_subset_singletons [RX_subset_bits] =
{
0x1,
0x2,
0x4,
0x8,
0x10,
0x20,
0x40,
0x80,
0x100,
0x200,
0x400,
0x800,
0x1000,
0x2000,
0x4000,
0x8000,
0x10000,
0x20000,
0x40000,
0x80000,
0x100000,
0x200000,
0x400000,
0x800000,
0x1000000,
0x2000000,
0x4000000,
0x8000000,
0x10000000,
0x20000000,
0x40000000,
0x80000000
};
#ifdef RX_DEBUG
#ifdef __STDC__
static void
print_cset (struct rx *rx, rx_Bitset cset, FILE * fp)
#else
static void
print_cset (rx, cset, fp)
struct rx *rx;
rx_Bitset cset;
FILE * fp;
#endif
{
int x;
fputc ('[', fp);
for (x = 0; x < rx->local_cset_size; ++x)
if (RX_bitset_member (cset, x))
{
if (isprint(x))
fputc (x, fp);
else
fprintf (fp, "\0%o ", x);
}
fputc (']', fp);
}
#endif /* RX_DEBUG */
static unsigned long rx_hash_masks[4] =
{
0x12488421,
0x96699669,
0xbe7dd7eb,
0xffffffff
};
/* Hash tables */
#ifdef __STDC__
RX_DECL struct rx_hash_item *
rx_hash_find (struct rx_hash * table,
unsigned long hash,
void * value,
struct rx_hash_rules * rules)
#else
RX_DECL struct rx_hash_item *
rx_hash_find (table, hash, value, rules)
struct rx_hash * table;
unsigned long hash;
void * value;
struct rx_hash_rules * rules;
#endif
{
rx_hash_eq eq = rules->eq;
int maskc = 0;
long mask = rx_hash_masks [0];
int bucket = (hash & mask) % 13;
while (table->children [bucket])
{
table = table->children [bucket];
++maskc;
mask = rx_hash_masks[maskc];
bucket = (hash & mask) % 13;
}
{
struct rx_hash_item * it = table->buckets[bucket];
while (it)
if (eq (it->data, value))
return it;
else
it = it->next_same_hash;
}
return 0;
}
#ifdef __STDC__
RX_DECL struct rx_hash_item *
rx_hash_store (struct rx_hash * table,
unsigned long hash,
void * value,
struct rx_hash_rules * rules)
#else
RX_DECL struct rx_hash_item *
rx_hash_store (table, hash, value, rules)
struct rx_hash * table;
unsigned long hash;
void * value;
struct rx_hash_rules * rules;
#endif
{
rx_hash_eq eq = rules->eq;
int maskc = 0;
long mask = rx_hash_masks[0];
int bucket = (hash & mask) % 13;
int depth = 0;
while (table->children [bucket])
{
table = table->children [bucket];
++maskc;
mask = rx_hash_masks[maskc];
bucket = (hash & mask) % 13;
++depth;
}
{
struct rx_hash_item * it = table->buckets[bucket];
while (it)
if (eq (it->data, value))
return it;
else
it = it->next_same_hash;
}
{
if ( (depth < 3)
&& (table->bucket_size [bucket] >= 4))
{
struct rx_hash * newtab = ((struct rx_hash *)
rules->hash_alloc (rules));
if (!newtab)
goto add_to_bucket;
bzero (newtab, sizeof (*newtab));
newtab->parent = table;
{
struct rx_hash_item * them = table->buckets[bucket];
unsigned long newmask = rx_hash_masks[maskc + 1];
while (them)
{
struct rx_hash_item * save = them->next_same_hash;
int new_buck = (them->hash & newmask) % 13;
them->next_same_hash = newtab->buckets[new_buck];
newtab->buckets[new_buck] = them;
them->table = newtab;
them = save;
++newtab->bucket_size[new_buck];
++newtab->refs;
}
table->refs = (table->refs - table->bucket_size[bucket] + 1);
table->bucket_size[bucket] = 0;
table->buckets[bucket] = 0;
table->children[bucket] = newtab;
table = newtab;
bucket = (hash & newmask) % 13;
}
}
}
add_to_bucket:
{
struct rx_hash_item * it = ((struct rx_hash_item *)
rules->hash_item_alloc (rules, value));
if (!it)
return 0;
it->hash = hash;
it->table = table;
/* DATA and BINDING are to be set in hash_item_alloc */
it->next_same_hash = table->buckets [bucket];
table->buckets[bucket] = it;
++table->bucket_size [bucket];
++table->refs;
return it;
}
}
#ifdef __STDC__
RX_DECL void
rx_hash_free (struct rx_hash_item * it, struct rx_hash_rules * rules)
#else
RX_DECL void
rx_hash_free (it, rules)
struct rx_hash_item * it;
struct rx_hash_rules * rules;
#endif
{
if (it)
{
struct rx_hash * table = it->table;
unsigned long hash = it->hash;
int depth = (table->parent
? (table->parent->parent
? (table->parent->parent->parent
? 3
: 2)
: 1)
: 0);
int bucket = (hash & rx_hash_masks [depth]) % 13;
struct rx_hash_item ** pos = &table->buckets [bucket];
while (*pos != it)
pos = &(*pos)->next_same_hash;
*pos = it->next_same_hash;
rules->free_hash_item (it, rules);
--table->bucket_size[bucket];
--table->refs;
while (!table->refs && depth)
{
struct rx_hash * save = table;
table = table->parent;
--depth;
bucket = (hash & rx_hash_masks [depth]) % 13;
--table->refs;
table->children[bucket] = 0;
rules->free_hash (save, rules);
}
}
}
#ifdef __STDC__
RX_DECL void
rx_free_hash_table (struct rx_hash * tab, rx_hash_freefn freefn,
struct rx_hash_rules * rules)
#else
RX_DECL void
rx_free_hash_table (tab, freefn, rules)
struct rx_hash * tab;
rx_hash_freefn freefn;
struct rx_hash_rules * rules;
#endif
{
int x;
for (x = 0; x < 13; ++x)
if (tab->children[x])
{
rx_free_hash_table (tab->children[x], freefn, rules);
rules->free_hash (tab->children[x], rules);
}
else
{
struct rx_hash_item * them = tab->buckets[x];
while (them)
{
struct rx_hash_item * that = them;
them = that->next_same_hash;
freefn (that);
rules->free_hash_item (that, rules);
}
}
}
/* Utilities for manipulating bitset represntations of characters sets. */
#ifdef __STDC__
RX_DECL rx_Bitset
rx_cset (struct rx *rx)
#else
RX_DECL rx_Bitset
rx_cset (rx)
struct rx *rx;
#endif
{
rx_Bitset b = (rx_Bitset) malloc (rx_sizeof_bitset (rx->local_cset_size));
if (b)
rx_bitset_null (rx->local_cset_size, b);
return b;
}
#ifdef __STDC__
RX_DECL rx_Bitset
rx_copy_cset (struct rx *rx, rx_Bitset a)
#else
RX_DECL rx_Bitset
rx_copy_cset (rx, a)
struct rx *rx;
rx_Bitset a;
#endif
{
rx_Bitset cs = rx_cset (rx);
if (cs)
rx_bitset_union (rx->local_cset_size, cs, a);
return cs;
}
#ifdef __STDC__
RX_DECL void
rx_free_cset (struct rx * rx, rx_Bitset c)
#else
RX_DECL void
rx_free_cset (rx, c)
struct rx * rx;
rx_Bitset c;
#endif
{
if (c)
free ((char *)c);
}
/* Hash table memory allocation policy for the regexp compiler */
#ifdef __STDC__
static struct rx_hash *
compiler_hash_alloc (struct rx_hash_rules * rules)
#else
static struct rx_hash *
compiler_hash_alloc (rules)
struct rx_hash_rules * rules;
#endif
{
return (struct rx_hash *)malloc (sizeof (struct rx_hash));
}
#ifdef __STDC__
static struct rx_hash_item *
compiler_hash_item_alloc (struct rx_hash_rules * rules, void * value)
#else
static struct rx_hash_item *
compiler_hash_item_alloc (rules, value)
struct rx_hash_rules * rules;
void * value;
#endif
{
struct rx_hash_item * it;
it = (struct rx_hash_item *)malloc (sizeof (*it));
if (it)
{
it->data = value;
it->binding = 0;
}
return it;
}
#ifdef __STDC__
static void
compiler_free_hash (struct rx_hash * tab,
struct rx_hash_rules * rules)
#else
static void
compiler_free_hash (tab, rules)
struct rx_hash * tab;
struct rx_hash_rules * rules;
#endif
{
free ((char *)tab);
}
#ifdef __STDC__
static void
compiler_free_hash_item (struct rx_hash_item * item,
struct rx_hash_rules * rules)
#else
static void
compiler_free_hash_item (item, rules)
struct rx_hash_item * item;
struct rx_hash_rules * rules;
#endif
{
free ((char *)item);
}
/* This page: REXP_NODE (expression tree) structures. */
#ifdef __STDC__
RX_DECL struct rexp_node *
rexp_node (struct rx *rx,
enum rexp_node_type type)
#else
RX_DECL struct rexp_node *
rexp_node (rx, type)
struct rx *rx;
enum rexp_node_type type;
#endif
{
struct rexp_node *n;
n = (struct rexp_node *)malloc (sizeof (*n));
bzero (n, sizeof (*n));
if (n)
n->type = type;
return n;
}
/* free_rexp_node assumes that the bitset passed to rx_mk_r_cset
* can be freed using rx_free_cset.
*/
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_cset (struct rx * rx,
rx_Bitset b)
#else
RX_DECL struct rexp_node *
rx_mk_r_cset (rx, b)
struct rx * rx;
rx_Bitset b;
#endif
{
struct rexp_node * n = rexp_node (rx, r_cset);
if (n)
n->params.cset = b;
return n;
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_concat (struct rx * rx,
struct rexp_node * a,
struct rexp_node * b)
#else
RX_DECL struct rexp_node *
rx_mk_r_concat (rx, a, b)
struct rx * rx;
struct rexp_node * a;
struct rexp_node * b;
#endif
{
struct rexp_node * n = rexp_node (rx, r_concat);
if (n)
{
n->params.pair.left = a;
n->params.pair.right = b;
}
return n;
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_alternate (struct rx * rx,
struct rexp_node * a,
struct rexp_node * b)
#else
RX_DECL struct rexp_node *
rx_mk_r_alternate (rx, a, b)
struct rx * rx;
struct rexp_node * a;
struct rexp_node * b;
#endif
{
struct rexp_node * n = rexp_node (rx, r_alternate);
if (n)
{
n->params.pair.left = a;
n->params.pair.right = b;
}
return n;
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_opt (struct rx * rx,
struct rexp_node * a)
#else
RX_DECL struct rexp_node *
rx_mk_r_opt (rx, a)
struct rx * rx;
struct rexp_node * a;
#endif
{
struct rexp_node * n = rexp_node (rx, r_opt);
if (n)
{
n->params.pair.left = a;
n->params.pair.right = 0;
}
return n;
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_star (struct rx * rx,
struct rexp_node * a)
#else
RX_DECL struct rexp_node *
rx_mk_r_star (rx, a)
struct rx * rx;
struct rexp_node * a;
#endif
{
struct rexp_node * n = rexp_node (rx, r_star);
if (n)
{
n->params.pair.left = a;
n->params.pair.right = 0;
}
return n;
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_2phase_star (struct rx * rx,
struct rexp_node * a,
struct rexp_node * b)
#else
RX_DECL struct rexp_node *
rx_mk_r_2phase_star (rx, a, b)
struct rx * rx;
struct rexp_node * a;
struct rexp_node * b;
#endif
{
struct rexp_node * n = rexp_node (rx, r_2phase_star);
if (n)
{
n->params.pair.left = a;
n->params.pair.right = b;
}
return n;
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_side_effect (struct rx * rx,
rx_side_effect a)
#else
RX_DECL struct rexp_node *
rx_mk_r_side_effect (rx, a)
struct rx * rx;
rx_side_effect a;
#endif
{
struct rexp_node * n = rexp_node (rx, r_side_effect);
if (n)
{
n->params.side_effect = a;
n->params.pair.right = 0;
}
return n;
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_mk_r_data (struct rx * rx,
void * a)
#else
RX_DECL struct rexp_node *
rx_mk_r_data (rx, a)
struct rx * rx;
void * a;
#endif
{
struct rexp_node * n = rexp_node (rx, r_data);
if (n)
{
n->params.pair.left = a;
n->params.pair.right = 0;
}
return n;
}
#ifdef __STDC__
RX_DECL void
rx_free_rexp (struct rx * rx, struct rexp_node * node)
#else
RX_DECL void
rx_free_rexp (rx, node)
struct rx * rx;
struct rexp_node * node;
#endif
{
if (node)
{
switch (node->type)
{
case r_cset:
if (node->params.cset)
rx_free_cset (rx, node->params.cset);
case r_side_effect:
break;
case r_concat:
case r_alternate:
case r_2phase_star:
case r_opt:
case r_star:
rx_free_rexp (rx, node->params.pair.left);
rx_free_rexp (rx, node->params.pair.right);
break;
case r_data:
/* This shouldn't occur. */
break;
}
free ((char *)node);
}
}
#ifdef __STDC__
RX_DECL struct rexp_node *
rx_copy_rexp (struct rx *rx,
struct rexp_node *node)
#else
RX_DECL struct rexp_node *
rx_copy_rexp (rx, node)
struct rx *rx;
struct rexp_node *node;
#endif
{
if (!node)
return 0;
else
{
struct rexp_node *n = rexp_node (rx, node->type);
if (!n)
return 0;
switch (node->type)
{
case r_cset:
n->params.cset = rx_copy_cset (rx, node->params.cset);
if (!n->params.cset)
{
rx_free_rexp (rx, n);
return 0;
}
break;
case r_side_effect:
n->params.side_effect = node->params.side_effect;
break;
case r_concat:
case r_alternate:
case r_opt:
case r_2phase_star:
case r_star:
n->params.pair.left =
rx_copy_rexp (rx, node->params.pair.left);
n->params.pair.right =
rx_copy_rexp (rx, node->params.pair.right);
if ( (node->params.pair.left && !n->params.pair.left)
|| (node->params.pair.right && !n->params.pair.right))
{
rx_free_rexp (rx, n);
return 0;
}
break;
case r_data:
/* shouldn't happen */
break;
}
return n;
}
}
/* This page: functions to build and destroy graphs that describe nfa's */
/* Constructs a new nfa node. */
#ifdef __STDC__
RX_DECL struct rx_nfa_state *
rx_nfa_state (struct rx *rx)
#else
RX_DECL struct rx_nfa_state *
rx_nfa_state (rx)
struct rx *rx;
#endif
{
struct rx_nfa_state * n = (struct rx_nfa_state *)malloc (sizeof (*n));
if (!n)
return 0;
bzero (n, sizeof (*n));
n->next = rx->nfa_states;
rx->nfa_states = n;
return n;
}
#ifdef __STDC__
RX_DECL void
rx_free_nfa_state (struct rx_nfa_state * n)
#else
RX_DECL void
rx_free_nfa_state (n)
struct rx_nfa_state * n;
#endif
{
free ((char *)n);
}
/* This looks up an nfa node, given a numeric id. Numeric id's are
* assigned after the nfa has been built.
*/
#ifdef __STDC__
RX_DECL struct rx_nfa_state *
rx_id_to_nfa_state (struct rx * rx,
int id)
#else
RX_DECL struct rx_nfa_state *
rx_id_to_nfa_state (rx, id)
struct rx * rx;
int id;
#endif
{
struct rx_nfa_state * n;
for (n = rx->nfa_states; n; n = n->next)
if (n->id == id)
return n;
return 0;
}
/* This adds an edge between two nodes, but doesn't initialize the
* edge label.
*/
#ifdef __STDC__
RX_DECL struct rx_nfa_edge *
rx_nfa_edge (struct rx *rx,
enum rx_nfa_etype type,
struct rx_nfa_state *start,
struct rx_nfa_state *dest)
#else
RX_DECL struct rx_nfa_edge *
rx_nfa_edge (rx, type, start, dest)
struct rx *rx;
enum rx_nfa_etype type;
struct rx_nfa_state *start;
struct rx_nfa_state *dest;
#endif
{
struct rx_nfa_edge *e;
e = (struct rx_nfa_edge *)malloc (sizeof (*e));
if (!e)
return 0;
e->next = start->edges;
start->edges = e;
e->type = type;
e->dest = dest;
return e;
}
#ifdef __STDC__
RX_DECL void
rx_free_nfa_edge (struct rx_nfa_edge * e)
#else
RX_DECL void
rx_free_nfa_edge (e)
struct rx_nfa_edge * e;
#endif
{
free ((char *)e);
}
/* This constructs a POSSIBLE_FUTURE, which is a kind epsilon-closure
* of an NFA. These are added to an nfa automaticly by eclose_nfa.
*/
#ifdef __STDC__
static struct rx_possible_future *
rx_possible_future (struct rx * rx,
struct rx_se_list * effects)
#else
static struct rx_possible_future *
rx_possible_future (rx, effects)
struct rx * rx;
struct rx_se_list * effects;
#endif
{
struct rx_possible_future *ec;
ec = (struct rx_possible_future *) malloc (sizeof (*ec));
if (!ec)
return 0;
ec->destset = 0;
ec->next = 0;
ec->effects = effects;
return ec;
}
#ifdef __STDC__
static void
rx_free_possible_future (struct rx_possible_future * pf)
#else
static void
rx_free_possible_future (pf)
struct rx_possible_future * pf;
#endif
{
free ((char *)pf);
}
#ifdef __STDC__
RX_DECL void
rx_free_nfa (struct rx *rx)
#else
RX_DECL void
rx_free_nfa (rx)
struct rx *rx;
#endif
{
while (rx->nfa_states)
{
while (rx->nfa_states->edges)
{
switch (rx->nfa_states->edges->type)
{
case ne_cset:
rx_free_cset (rx, rx->nfa_states->edges->params.cset);
break;
default:
break;
}
{
struct rx_nfa_edge * e;
e = rx->nfa_states->edges;
rx->nfa_states->edges = rx->nfa_states->edges->next;
rx_free_nfa_edge (e);
}
} /* while (rx->nfa_states->edges) */
{
/* Iterate over the partial epsilon closures of rx->nfa_states */
struct rx_possible_future * pf = rx->nfa_states->futures;
while (pf)
{
struct rx_possible_future * pft = pf;
pf = pf->next;
rx_free_possible_future (pft);
}
}
{
struct rx_nfa_state *n;
n = rx->nfa_states;
rx->nfa_states = rx->nfa_states->next;
rx_free_nfa_state (n);
}
}
}
/* This page: translating a pattern expression into an nfa and doing the
* static part of the nfa->super-nfa translation.
*/
/* This is the thompson regexp->nfa algorithm.
* It is modified to allow for `side-effect epsilons.' Those are
* edges that are taken whenever a similar epsilon edge would be,
* but which imply that some side effect occurs when the edge
* is taken.
*
* Side effects are used to model parts of the pattern langauge
* that are not regular (in the formal sense).
*/
#ifdef __STDC__
RX_DECL int
rx_build_nfa (struct rx *rx,
struct rexp_node *rexp,
struct rx_nfa_state **start,
struct rx_nfa_state **end)
#else
RX_DECL int
rx_build_nfa (rx, rexp, start, end)
struct rx *rx;
struct rexp_node *rexp;
struct rx_nfa_state **start;
struct rx_nfa_state **end;
#endif
{
struct rx_nfa_edge *edge;
/* Start & end nodes may have been allocated by the caller. */
*start = *start ? *start : rx_nfa_state (rx);
if (!*start)
return 0;
if (!rexp)
{
*end = *start;
return 1;
}
*end = *end ? *end : rx_nfa_state (rx);
if (!*end)
{
rx_free_nfa_state (*start);
return 0;
}
switch (rexp->type)
{
case r_data:
return 0;
case r_cset:
edge = rx_nfa_edge (rx, ne_cset, *start, *end);
if (!edge)
return 0;
edge->params.cset = rx_copy_cset (rx, rexp->params.cset);
if (!edge->params.cset)
{
rx_free_nfa_edge (edge);
return 0;
}
return 1;
case r_opt:
return (rx_build_nfa (rx, rexp->params.pair.left, start, end)
&& rx_nfa_edge (rx, ne_epsilon, *start, *end));
case r_star:
{
struct rx_nfa_state * star_start = 0;
struct rx_nfa_state * star_end = 0;
return (rx_build_nfa (rx, rexp->params.pair.left,
&star_start, &star_end)
&& star_start
&& star_end
&& rx_nfa_edge (rx, ne_epsilon, star_start, star_end)
&& rx_nfa_edge (rx, ne_epsilon, *start, star_start)
&& rx_nfa_edge (rx, ne_epsilon, star_end, *end)
&& rx_nfa_edge (rx, ne_epsilon, star_end, star_start));
}
case r_2phase_star:
{
struct rx_nfa_state * star_start = 0;
struct rx_nfa_state * star_end = 0;
struct rx_nfa_state * loop_exp_start = 0;
struct rx_nfa_state * loop_exp_end = 0;
return (rx_build_nfa (rx, rexp->params.pair.left,
&star_start, &star_end)
&& rx_build_nfa (rx, rexp->params.pair.right,
&loop_exp_start, &loop_exp_end)
&& star_start
&& star_end
&& loop_exp_end
&& loop_exp_start
&& rx_nfa_edge (rx, ne_epsilon, star_start, *end)
&& rx_nfa_edge (rx, ne_epsilon, *start, star_start)
&& rx_nfa_edge (rx, ne_epsilon, star_end, *end)
&& rx_nfa_edge (rx, ne_epsilon, star_end, loop_exp_start)
&& rx_nfa_edge (rx, ne_epsilon, loop_exp_end, star_start));
}
case r_concat:
{
struct rx_nfa_state *shared = 0;
return
(rx_build_nfa (rx, rexp->params.pair.left, start, &shared)
&& rx_build_nfa (rx, rexp->params.pair.right, &shared, end));
}
case r_alternate:
{
struct rx_nfa_state *ls = 0;
struct rx_nfa_state *le = 0;
struct rx_nfa_state *rs = 0;
struct rx_nfa_state *re = 0;
return (rx_build_nfa (rx, rexp->params.pair.left, &ls, &le)
&& rx_build_nfa (rx, rexp->params.pair.right, &rs, &re)
&& rx_nfa_edge (rx, ne_epsilon, *start, ls)
&& rx_nfa_edge (rx, ne_epsilon, *start, rs)
&& rx_nfa_edge (rx, ne_epsilon, le, *end)
&& rx_nfa_edge (rx, ne_epsilon, re, *end));
}
case r_side_effect:
edge = rx_nfa_edge (rx, ne_side_effect, *start, *end);
if (!edge)
return 0;
edge->params.side_effect = rexp->params.side_effect;
return 1;
}
/* this should never happen */
return 0;
}
/* RX_NAME_NFA_STATES identifies all nodes with outgoing non-epsilon
* transitions. Only these nodes can occur in super-states.
* All nodes are given an integer id.
* The id is non-negative if the node has non-epsilon out-transitions, negative
* otherwise (this is because we want the non-negative ids to be used as
* array indexes in a few places).
*/
#ifdef __STDC__
RX_DECL void
rx_name_nfa_states (struct rx *rx)
#else
RX_DECL void
rx_name_nfa_states (rx)
struct rx *rx;
#endif
{
struct rx_nfa_state *n = rx->nfa_states;
rx->nodec = 0;
rx->epsnodec = -1;
while (n)
{
struct rx_nfa_edge *e = n->edges;
if (n->is_start)
n->eclosure_needed = 1;
while (e)
{
switch (e->type)
{
case ne_epsilon:
case ne_side_effect:
break;
case ne_cset:
n->id = rx->nodec++;
{
struct rx_nfa_edge *from_n = n->edges;
while (from_n)
{
from_n->dest->eclosure_needed = 1;
from_n = from_n->next;
}
}
goto cont;
}
e = e->next;
}
n->id = rx->epsnodec--;
cont:
n = n->next;
}
rx->epsnodec = -rx->epsnodec;
}
/* This page: data structures for the static part of the nfa->supernfa
* translation.
*
* There are side effect lists -- lists of side effects occuring
* along an uninterrupted, acyclic path of side-effect epsilon edges.
* Such paths are collapsed to single edges in the course of computing
* epsilon closures. Such single edges are labled with a list of all
* the side effects entailed in crossing them. Like lists of side
* effects are made == by the constructors below.
*
* There are also nfa state sets. These are used to hold a list of all
* states reachable from a starting state for a given type of transition
* and side effect list. These are also hash-consed.
*/
/* The next several functions compare, construct, etc. lists of side
* effects. See ECLOSE_NFA (below) for details.
*/
/* Ordering of rx_se_list
* (-1, 0, 1 return value convention).
*/
#ifdef __STDC__
static int
se_list_cmp (void * va, void * vb)
#else
static int
se_list_cmp (va, vb)
void * va;
void * vb;
#endif
{
struct rx_se_list * a = (struct rx_se_list *)va;
struct rx_se_list * b = (struct rx_se_list *)vb;
return ((va == vb)
? 0
: (!va
? -1
: (!vb
? 1
: ((long)a->car < (long)b->car
? 1
: ((long)a->car > (long)b->car
? -1
: se_list_cmp ((void *)a->cdr, (void *)b->cdr))))));
}
#ifdef __STDC__
static int
se_list_equal (void * va, void * vb)
#else
static int
se_list_equal (va, vb)
void * va;
void * vb;
#endif
{
return !(se_list_cmp (va, vb));
}
static struct rx_hash_rules se_list_hash_rules =
{
se_list_equal,
compiler_hash_alloc,
compiler_free_hash,
compiler_hash_item_alloc,
compiler_free_hash_item
};
#ifdef __STDC__
static struct rx_se_list *
side_effect_cons (struct rx * rx,
void * se, struct rx_se_list * list)
#else
static struct rx_se_list *
side_effect_cons (rx, se, list)
struct rx * rx;
void * se;
struct rx_se_list * list;
#endif
{
struct rx_se_list * l;
l = ((struct rx_se_list *) malloc (sizeof (*l)));
if (!l)
return 0;
l->car = se;
l->cdr = list;
return l;
}
#ifdef __STDC__
static struct rx_se_list *
hash_cons_se_prog (struct rx * rx,
struct rx_hash * memo,
void * car, struct rx_se_list * cdr)
#else
static struct rx_se_list *
hash_cons_se_prog (rx, memo, car, cdr)
struct rx * rx;
struct rx_hash * memo;
void * car;
struct rx_se_list * cdr;
#endif
{
long hash = (long)car ^ (long)cdr;
struct rx_se_list template;
template.car = car;
template.cdr = cdr;
{
struct rx_hash_item * it = rx_hash_store (memo, hash,
(void *)&template,
&se_list_hash_rules);
if (!it)
return 0;
if (it->data == (void *)&template)
{
struct rx_se_list * consed;
consed = (struct rx_se_list *) malloc (sizeof (*consed));
*consed = template;
it->data = (void *)consed;
}
return (struct rx_se_list *)it->data;
}
}
#ifdef __STDC__
static struct rx_se_list *
hash_se_prog (struct rx * rx, struct rx_hash * memo, struct rx_se_list * prog)
#else
static struct rx_se_list *
hash_se_prog (rx, memo, prog)
struct rx * rx;
struct rx_hash * memo;
struct rx_se_list * prog;
#endif
{
struct rx_se_list * answer = 0;
while (prog)
{
answer = hash_cons_se_prog (rx, memo, prog->car, answer);
if (!answer)
return 0;
prog = prog->cdr;
}
return answer;
}
#ifdef __STDC__
static int
nfa_set_cmp (void * va, void * vb)
#else
static int
nfa_set_cmp (va, vb)
void * va;
void * vb;
#endif
{
struct rx_nfa_state_set * a = (struct rx_nfa_state_set *)va;
struct rx_nfa_state_set * b = (struct rx_nfa_state_set *)vb;
return ((va == vb)
? 0
: (!va
? -1
: (!vb
? 1
: (a->car->id < b->car->id
? 1
: (a->car->id > b->car->id
? -1
: nfa_set_cmp ((void *)a->cdr, (void *)b->cdr))))));
}
#ifdef __STDC__
static int
nfa_set_equal (void * va, void * vb)
#else
static int
nfa_set_equal (va, vb)
void * va;
void * vb;
#endif
{
return !nfa_set_cmp (va, vb);
}
static struct rx_hash_rules nfa_set_hash_rules =
{
nfa_set_equal,
compiler_hash_alloc,
compiler_free_hash,
compiler_hash_item_alloc,
compiler_free_hash_item
};
#ifdef __STDC__
static struct rx_nfa_state_set *
nfa_set_cons (struct rx * rx,
struct rx_hash * memo, struct rx_nfa_state * state,
struct rx_nfa_state_set * set)
#else
static struct rx_nfa_state_set *
nfa_set_cons (rx, memo, state, set)
struct rx * rx;
struct rx_hash * memo;
struct rx_nfa_state * state;
struct rx_nfa_state_set * set;
#endif
{
struct rx_nfa_state_set template;
struct rx_hash_item * node;
template.car = state;
template.cdr = set;
node = rx_hash_store (memo,
(((long)state) >> 8) ^ (long)set,
&template, &nfa_set_hash_rules);
if (!node)
return 0;
if (node->data == &template)
{
struct rx_nfa_state_set * l;
l = (struct rx_nfa_state_set *) malloc (sizeof (*l));
node->data = (void *) l;
if (!l)
return 0;
*l = template;
}
return (struct rx_nfa_state_set *)node->data;
}
#ifdef __STDC__
static struct rx_nfa_state_set *
nfa_set_enjoin (struct rx * rx,
struct rx_hash * memo, struct rx_nfa_state * state,
struct rx_nfa_state_set * set)
#else
static struct rx_nfa_state_set *
nfa_set_enjoin (rx, memo, state, set)
struct rx * rx;
struct rx_hash * memo;
struct rx_nfa_state * state;
struct rx_nfa_state_set * set;
#endif
{
if (!set || state->id < set->car->id)
return nfa_set_cons (rx, memo, state, set);
if (state->id == set->car->id)
return set;
else
{
struct rx_nfa_state_set * newcdr
= nfa_set_enjoin (rx, memo, state, set->cdr);
if (newcdr != set->cdr)
set = nfa_set_cons (rx, memo, set->car, newcdr);
return set;
}
}
/* This page: computing epsilon closures. The closures aren't total.
* Each node's closures are partitioned according to the side effects entailed
* along the epsilon edges. Return true on success.
*/
struct eclose_frame
{
struct rx_se_list *prog_backwards;
};
#ifdef __STDC__
static int
eclose_node (struct rx *rx, struct rx_nfa_state *outnode,
struct rx_nfa_state *node, struct eclose_frame *frame)
#else
static int
eclose_node (rx, outnode, node, frame)
struct rx *rx;
struct rx_nfa_state *outnode;
struct rx_nfa_state *node;
struct eclose_frame *frame;
#endif
{
struct rx_nfa_edge *e = node->edges;
/* For each node, we follow all epsilon paths to build the closure.
* The closure omits nodes that have only epsilon edges.
* The closure is split into partial closures -- all the states in
* a partial closure are reached by crossing the same list of
* of side effects (though not necessarily the same path).
*/
if (node->mark)
return 1;
node->mark = 1;
if (node->id >= 0 || node->is_final)
{
struct rx_possible_future **ec;
struct rx_se_list * prog_in_order
= ((struct rx_se_list *)hash_se_prog (rx,
&rx->se_list_memo,
frame->prog_backwards));
int cmp;
ec = &outnode->futures;
while (*ec)
{
cmp = se_list_cmp ((void *)(*ec)->effects, (void *)prog_in_order);
if (cmp <= 0)
break;
ec = &(*ec)->next;
}
if (!*ec || (cmp < 0))
{
struct rx_possible_future * saved = *ec;
*ec = rx_possible_future (rx, prog_in_order);
(*ec)->next = saved;
if (!*ec)
return 0;
}
if (node->id >= 0)
{
(*ec)->destset = nfa_set_enjoin (rx, &rx->set_list_memo,
node, (*ec)->destset);
if (!(*ec)->destset)
return 0;
}
}
while (e)
{
switch (e->type)
{
case ne_epsilon:
if (!eclose_node (rx, outnode, e->dest, frame))
return 0;
break;
case ne_side_effect:
{
frame->prog_backwards = side_effect_cons (rx,
e->params.side_effect,
frame->prog_backwards);
if (!frame->prog_backwards)
return 0;
if (!eclose_node (rx, outnode, e->dest, frame))
return 0;
{
struct rx_se_list * dying = frame->prog_backwards;
frame->prog_backwards = frame->prog_backwards->cdr;
free ((char *)dying);
}
break;
}
default:
break;
}
e = e->next;
}
node->mark = 0;
return 1;
}
#ifdef __STDC__
RX_DECL int
rx_eclose_nfa (struct rx *rx)
#else
RX_DECL int
rx_eclose_nfa (rx)
struct rx *rx;
#endif
{
struct rx_nfa_state *n = rx->nfa_states;
struct eclose_frame frame;
static int rx_id = 0;
frame.prog_backwards = 0;
rx->rx_id = rx_id++;
bzero (&rx->se_list_memo, sizeof (rx->se_list_memo));
bzero (&rx->set_list_memo, sizeof (rx->set_list_memo));
while (n)
{
n->futures = 0;
if (n->eclosure_needed && !eclose_node (rx, n, n, &frame))
return 0;
/* clear_marks (rx); */
n = n->next;
}
return 1;
}
/* This deletes epsilon edges from an NFA. After running eclose_node,
* we have no more need for these edges. They are removed to simplify
* further operations on the NFA.
*/
#ifdef __STDC__
RX_DECL void
rx_delete_epsilon_transitions (struct rx *rx)
#else
RX_DECL void
rx_delete_epsilon_transitions (rx)
struct rx *rx;
#endif
{
struct rx_nfa_state *n = rx->nfa_states;
struct rx_nfa_edge **e;
while (n)
{
e = &n->edges;
while (*e)
{
struct rx_nfa_edge *t;
switch ((*e)->type)
{
case ne_epsilon:
case ne_side_effect:
t = *e;
*e = t->next;
rx_free_nfa_edge (t);
break;
default:
e = &(*e)->next;
break;
}
}
n = n->next;
}
}
/* This page: storing the nfa in a contiguous region of memory for
* subsequent conversion to a super-nfa.
*/
/* This is for qsort on an array of nfa_states. The order
* is based on state ids and goes
* [0...MAX][MIN..-1] where (MAX>=0) and (MIN<0)
* This way, positive ids double as array indices.
*/
#ifdef __STDC__
static int
nfacmp (void * va, void * vb)
#else
static int
nfacmp (va, vb)
void * va;
void * vb;
#endif
{
struct rx_nfa_state **a = (struct rx_nfa_state **)va;
struct rx_nfa_state **b = (struct rx_nfa_state **)vb;
return (*a == *b /* &&&& 3.18 */
? 0
: (((*a)->id < 0) == ((*b)->id < 0)
? (((*a)->id < (*b)->id) ? -1 : 1)
: (((*a)->id < 0)
? 1 : -1)));
}
#ifdef __STDC__
static int
count_hash_nodes (struct rx_hash * st)
#else
static int
count_hash_nodes (st)
struct rx_hash * st;
#endif
{
int x;
int count = 0;
for (x = 0; x < 13; ++x)
count += ((st->children[x])
? count_hash_nodes (st->children[x])
: st->bucket_size[x]);
return count;
}
#ifdef __STDC__
static void
se_memo_freer (struct rx_hash_item * node)
#else
static void
se_memo_freer (node)
struct rx_hash_item * node;
#endif
{
free ((char *)node->data);
}
#ifdef __STDC__
static void
nfa_set_freer (struct rx_hash_item * node)
#else
static void
nfa_set_freer (node)
struct rx_hash_item * node;
#endif
{
free ((char *)node->data);
}
/* This copies an entire NFA into a single malloced block of memory.
* Mostly this is for compatability with regex.c, though it is convenient
* to have the nfa nodes in an array.
*/
#ifdef __STDC__
RX_DECL int
rx_compactify_nfa (struct rx *rx,
void **mem, unsigned long *size)
#else
RX_DECL int
rx_compactify_nfa (rx, mem, size)
struct rx *rx;
void **mem;
unsigned long *size;
#endif
{
int total_nodec;
struct rx_nfa_state *n;
int edgec = 0;
int eclosec = 0;
int se_list_consc = count_hash_nodes (&rx->se_list_memo);
int nfa_setc = count_hash_nodes (&rx->set_list_memo);
unsigned long total_size;
/* This takes place in two stages. First, the total size of the
* nfa is computed, then structures are copied.
*/
n = rx->nfa_states;
total_nodec = 0;
while (n)
{
struct rx_nfa_edge *e = n->edges;
struct rx_possible_future *ec = n->futures;
++total_nodec;
while (e)
{
++edgec;
e = e->next;
}
while (ec)
{
++eclosec;
ec = ec->next;
}
n = n->next;
}
total_size = (total_nodec * sizeof (struct rx_nfa_state)
+ edgec * rx_sizeof_bitset (rx->local_cset_size)
+ edgec * sizeof (struct rx_nfa_edge)
+ nfa_setc * sizeof (struct rx_nfa_state_set)
+ eclosec * sizeof (struct rx_possible_future)
+ se_list_consc * sizeof (struct rx_se_list)
+ rx->reserved);
if (total_size > *size)
{
*mem = remalloc (*mem, total_size);
if (*mem)
*size = total_size;
else
return 0;
}
/* Now we've allocated the memory; this copies the NFA. */
{
static struct rx_nfa_state **scratch = 0;
static int scratch_alloc = 0;
struct rx_nfa_state *state_base = (struct rx_nfa_state *) * mem;
struct rx_nfa_state *new_state = state_base;
struct rx_nfa_edge *new_edge =
(struct rx_nfa_edge *)
((char *) state_base + total_nodec * sizeof (struct rx_nfa_state));
struct rx_se_list * new_se_list =
(struct rx_se_list *)
((char *)new_edge + edgec * sizeof (struct rx_nfa_edge));
struct rx_possible_future *new_close =
((struct rx_possible_future *)
((char *) new_se_list
+ se_list_consc * sizeof (struct rx_se_list)));
struct rx_nfa_state_set * new_nfa_set =
((struct rx_nfa_state_set *)
((char *)new_close + eclosec * sizeof (struct rx_possible_future)));
char *new_bitset =
((char *) new_nfa_set + nfa_setc * sizeof (struct rx_nfa_state_set));
int x;
struct rx_nfa_state *n;
if (scratch_alloc < total_nodec)
{
scratch = ((struct rx_nfa_state **)
remalloc (scratch, total_nodec * sizeof (*scratch)));
if (scratch)
scratch_alloc = total_nodec;
else
{
scratch_alloc = 0;
return 0;
}
}
for (x = 0, n = rx->nfa_states; n; n = n->next)
scratch[x++] = n;
qsort (scratch, total_nodec,
sizeof (struct rx_nfa_state *), (int (*)())nfacmp);
for (x = 0; x < total_nodec; ++x)
{
struct rx_possible_future *eclose = scratch[x]->futures;
struct rx_nfa_edge *edge = scratch[x]->edges;
struct rx_nfa_state *cn = new_state++;
cn->futures = 0;
cn->edges = 0;
cn->next = (x == total_nodec - 1) ? 0 : (cn + 1);
cn->id = scratch[x]->id;
cn->is_final = scratch[x]->is_final;
cn->is_start = scratch[x]->is_start;
cn->mark = 0;
while (edge)
{
int indx = (edge->dest->id < 0
? (total_nodec + edge->dest->id)
: edge->dest->id);
struct rx_nfa_edge *e = new_edge++;
rx_Bitset cset = (rx_Bitset) new_bitset;
new_bitset += rx_sizeof_bitset (rx->local_cset_size);
rx_bitset_null (rx->local_cset_size, cset);
rx_bitset_union (rx->local_cset_size, cset, edge->params.cset);
e->next = cn->edges;
cn->edges = e;
e->type = edge->type;
e->dest = state_base + indx;
e->params.cset = cset;
edge = edge->next;
}
while (eclose)
{
struct rx_possible_future *ec = new_close++;
struct rx_hash_item * sp;
struct rx_se_list ** sepos;
struct rx_se_list * sesrc;
struct rx_nfa_state_set * destlst;
struct rx_nfa_state_set ** destpos;
ec->next = cn->futures;
cn->futures = ec;
for (sepos = &ec->effects, sesrc = eclose->effects;
sesrc;
sesrc = sesrc->cdr, sepos = &(*sepos)->cdr)
{
sp = rx_hash_find (&rx->se_list_memo,
(long)sesrc->car ^ (long)sesrc->cdr,
sesrc, &se_list_hash_rules);
if (sp->binding)
{
sesrc = (struct rx_se_list *)sp->binding;
break;
}
*new_se_list = *sesrc;
sp->binding = (void *)new_se_list;
*sepos = new_se_list;
++new_se_list;
}
*sepos = sesrc;
for (destpos = &ec->destset, destlst = eclose->destset;
destlst;
destpos = &(*destpos)->cdr, destlst = destlst->cdr)
{
sp = rx_hash_find (&rx->set_list_memo,
((((long)destlst->car) >> 8)
^ (long)destlst->cdr),
destlst, &nfa_set_hash_rules);
if (sp->binding)
{
destlst = (struct rx_nfa_state_set *)sp->binding;
break;
}
*new_nfa_set = *destlst;
new_nfa_set->car = state_base + destlst->car->id;
sp->binding = (void *)new_nfa_set;
*destpos = new_nfa_set;
++new_nfa_set;
}
*destpos = destlst;
eclose = eclose->next;
}
}
}
rx_free_hash_table (&rx->se_list_memo, se_memo_freer, &se_list_hash_rules);
bzero (&rx->se_list_memo, sizeof (rx->se_list_memo));
rx_free_hash_table (&rx->set_list_memo, nfa_set_freer, &nfa_set_hash_rules);
bzero (&rx->set_list_memo, sizeof (rx->set_list_memo));
rx_free_nfa (rx);
rx->nfa_states = (struct rx_nfa_state *)*mem;
return 1;
}
/* The functions in the next several pages define the lazy-NFA-conversion used
* by matchers. The input to this construction is an NFA such as
* is built by compactify_nfa (rx.c). The output is the superNFA.
*/
/* Match engines can use arbitrary values for opcodes. So, the parse tree
* is built using instructions names (enum rx_opcode), but the superstate
* nfa is populated with mystery opcodes (void *).
*
* For convenience, here is an id table. The opcodes are == to their inxs
*
* The lables in re_search_2 would make good values for instructions.
*/
void * rx_id_instruction_table[rx_num_instructions] =
{
(void *) rx_backtrack_point,
(void *) rx_do_side_effects,
(void *) rx_cache_miss,
(void *) rx_next_char,
(void *) rx_backtrack,
(void *) rx_error_inx
};
/* Memory mgt. for superstate graphs. */
#ifdef __STDC__
static char *
rx_cache_malloc (struct rx_cache * cache, int bytes)
#else
static char *
rx_cache_malloc (cache, bytes)
struct rx_cache * cache;
int bytes;
#endif
{
while (cache->bytes_left < bytes)
{
if (cache->memory_pos)
cache->memory_pos = cache->memory_pos->next;
if (!cache->memory_pos)
{
cache->morecore (cache);
if (!cache->memory_pos)
return 0;
}
cache->bytes_left = cache->memory_pos->bytes;
cache->memory_addr = ((char *)cache->memory_pos
+ sizeof (struct rx_blocklist));
}
cache->bytes_left -= bytes;
{
char * addr = cache->memory_addr;
cache->memory_addr += bytes;
return addr;
}
}
#ifdef __STDC__
static void
rx_cache_free (struct rx_cache * cache,
struct rx_freelist ** freelist, char * mem)
#else
static void
rx_cache_free (cache, freelist, mem)
struct rx_cache * cache;
struct rx_freelist ** freelist;
char * mem;
#endif
{
struct rx_freelist * it = (struct rx_freelist *)mem;
it->next = *freelist;
*freelist = it;
}
/* The partially instantiated superstate graph has a transition
* table at every node. There is one entry for every character.
* This fills in the transition for a set.
*/
#ifdef __STDC__
static void
install_transition (struct rx_superstate *super,
struct rx_inx *answer, rx_Bitset trcset)
#else
static void
install_transition (super, answer, trcset)
struct rx_superstate *super;
struct rx_inx *answer;
rx_Bitset trcset;
#endif
{
struct rx_inx * transitions = super->transitions;
int chr;
for (chr = 0; chr < 256; )
if (!*trcset)
{
++trcset;
chr += 32;
}
else
{
RX_subset sub = *trcset;
RX_subset mask = 1;
int bound = chr + 32;
while (chr < bound)
{
if (sub & mask)
transitions [chr] = *answer;
++chr;
mask <<= 1;
}
++trcset;
}
}
#ifdef __STDC__
static int
qlen (struct rx_superstate * q)
#else
static int
qlen (q)
struct rx_superstate * q;
#endif
{
int count = 1;
struct rx_superstate * it;
if (!q)
return 0;
for (it = q->next_recyclable; it != q; it = it->next_recyclable)
++count;
return count;
}
#ifdef __STDC__
static void
check_cache (struct rx_cache * cache)
#else
static void
check_cache (cache)
struct rx_cache * cache;
#endif
{
struct rx_cache * you_fucked_up = 0;
int total = cache->superstates;
int semi = cache->semifree_superstates;
if (semi != qlen (cache->semifree_superstate))
check_cache (you_fucked_up);
if ((total - semi) != qlen (cache->lru_superstate))
check_cache (you_fucked_up);
}
/* When a superstate is old and neglected, it can enter a
* semi-free state. A semi-free state is slated to die.
* Incoming transitions to a semi-free state are re-written
* to cause an (interpreted) fault when they are taken.
* The fault handler revives the semi-free state, patches
* incoming transitions back to normal, and continues.
*
* The idea is basicly to free in two stages, aborting
* between the two if the state turns out to be useful again.
* When a free is aborted, the rescued superstate is placed
* in the most-favored slot to maximize the time until it
* is next semi-freed.
*/
#ifdef __STDC__
static void
semifree_superstate (struct rx_cache * cache)
#else
static void
semifree_superstate (cache)
struct rx_cache * cache;
#endif
{
int disqualified = cache->semifree_superstates;
if (disqualified == cache->superstates)
return;
while (cache->lru_superstate->locks)
{
cache->lru_superstate = cache->lru_superstate->next_recyclable;
++disqualified;
if (disqualified == cache->superstates)
return;
}
{
struct rx_superstate * it = cache->lru_superstate;
it->next_recyclable->prev_recyclable = it->prev_recyclable;
it->prev_recyclable->next_recyclable = it->next_recyclable;
cache->lru_superstate = (it == it->next_recyclable
? 0
: it->next_recyclable);
if (!cache->semifree_superstate)
{
cache->semifree_superstate = it;
it->next_recyclable = it;
it->prev_recyclable = it;
}
else
{
it->prev_recyclable = cache->semifree_superstate->prev_recyclable;
it->next_recyclable = cache->semifree_superstate;
it->prev_recyclable->next_recyclable = it;
it->next_recyclable->prev_recyclable = it;
}
{
struct rx_distinct_future *df;
it->is_semifree = 1;
++cache->semifree_superstates;
df = it->transition_refs;
if (df)
{
df->prev_same_dest->next_same_dest = 0;
for (df = it->transition_refs; df; df = df->next_same_dest)
{
df->future_frame.inx = cache->instruction_table[rx_cache_miss];
df->future_frame.data = 0;
df->future_frame.data_2 = (void *) df;
/* If there are any NEXT-CHAR instruction frames that
* refer to this state, we convert them to CACHE-MISS frames.
*/
if (!df->effects
&& (df->edge->options->next_same_super_edge[0]
== df->edge->options))
install_transition (df->present, &df->future_frame,
df->edge->cset);
}
df = it->transition_refs;
df->prev_same_dest->next_same_dest = df;
}
}
}
}
#ifdef __STDC__
static void
refresh_semifree_superstate (struct rx_cache * cache,
struct rx_superstate * super)
#else
static void
refresh_semifree_superstate (cache, super)
struct rx_cache * cache;
struct rx_superstate * super;
#endif
{
struct rx_distinct_future *df;
if (super->transition_refs)
{
super->transition_refs->prev_same_dest->next_same_dest = 0;
for (df = super->transition_refs; df; df = df->next_same_dest)
{
df->future_frame.inx = cache->instruction_table[rx_next_char];
df->future_frame.data = (void *) super->transitions;
/* CACHE-MISS instruction frames that refer to this state,
* must be converted to NEXT-CHAR frames.
*/
if (!df->effects
&& (df->edge->options->next_same_super_edge[0]
== df->edge->options))
install_transition (df->present, &df->future_frame,
df->edge->cset);
}
super->transition_refs->prev_same_dest->next_same_dest
= super->transition_refs;
}
if (cache->semifree_superstate == super)
cache->semifree_superstate = (super->prev_recyclable == super
? 0
: super->prev_recyclable);
super->next_recyclable->prev_recyclable = super->prev_recyclable;
super->prev_recyclable->next_recyclable = super->next_recyclable;
if (!cache->lru_superstate)
(cache->lru_superstate
= super->next_recyclable
= super->prev_recyclable
= super);
else
{
super->next_recyclable = cache->lru_superstate;
super->prev_recyclable = cache->lru_superstate->prev_recyclable;
super->next_recyclable->prev_recyclable = super;
super->prev_recyclable->next_recyclable = super;
}
super->is_semifree = 0;
--cache->semifree_superstates;
}
#ifdef __STDC__
static void
rx_refresh_this_superstate (struct rx_cache * cache, struct rx_superstate * superstate)
#else
static void
rx_refresh_this_superstate (cache, superstate)
struct rx_cache * cache;
struct rx_superstate * superstate;
#endif
{
if (superstate->is_semifree)
refresh_semifree_superstate (cache, superstate);
else if (cache->lru_superstate == superstate)
cache->lru_superstate = superstate->next_recyclable;
else if (superstate != cache->lru_superstate->prev_recyclable)
{
superstate->next_recyclable->prev_recyclable
= superstate->prev_recyclable;
superstate->prev_recyclable->next_recyclable
= superstate->next_recyclable;
superstate->next_recyclable = cache->lru_superstate;
superstate->prev_recyclable = cache->lru_superstate->prev_recyclable;
superstate->next_recyclable->prev_recyclable = superstate;
superstate->prev_recyclable->next_recyclable = superstate;
}
}
#ifdef __STDC__
static void
release_superset_low (struct rx_cache * cache,
struct rx_superset *set)
#else
static void
release_superset_low (cache, set)
struct rx_cache * cache;
struct rx_superset *set;
#endif
{
if (!--set->refs)
{
if (set->cdr)
release_superset_low (cache, set->cdr);
set->starts_for = 0;
rx_hash_free
(rx_hash_find
(&cache->superset_table,
(unsigned long)set->car ^ set->id ^ (unsigned long)set->cdr,
(void *)set,
&cache->superset_hash_rules),
&cache->superset_hash_rules);
rx_cache_free (cache, &cache->free_supersets, (char *)set);
}
}
#ifdef __STDC__
RX_DECL void
rx_release_superset (struct rx *rx,
struct rx_superset *set)
#else
RX_DECL void
rx_release_superset (rx, set)
struct rx *rx;
struct rx_superset *set;
#endif
{
release_superset_low (rx->cache, set);
}
/* This tries to add a new superstate to the superstate freelist.
* It might, as a result, free some edge pieces or hash tables.
* If nothing can be freed because too many locks are being held, fail.
*/
#ifdef __STDC__
static int
rx_really_free_superstate (struct rx_cache * cache)
#else
static int
rx_really_free_superstate (cache)
struct rx_cache * cache;
#endif
{
int locked_superstates = 0;
struct rx_superstate * it;
if (!cache->superstates)
return 0;
{
/* This is a total guess. The idea is that we should expect as
* many misses as we've recently experienced. I.e., cache->misses
* should be the same as cache->semifree_superstates.
*/
while ((cache->hits + cache->misses) > cache->superstates_allowed)
{
cache->hits >>= 1;
cache->misses >>= 1;
}
if ( ((cache->hits + cache->misses) * cache->semifree_superstates)
< (cache->superstates * cache->misses))
{
semifree_superstate (cache);
semifree_superstate (cache);
}
}
while (cache->semifree_superstate && cache->semifree_superstate->locks)
{
refresh_semifree_superstate (cache, cache->semifree_superstate);
++locked_superstates;
if (locked_superstates == cache->superstates)
return 0;
}
if (cache->semifree_superstate)
{
it = cache->semifree_superstate;
it->next_recyclable->prev_recyclable = it->prev_recyclable;
it->prev_recyclable->next_recyclable = it->next_recyclable;
cache->semifree_superstate = ((it == it->next_recyclable)
? 0
: it->next_recyclable);
--cache->semifree_superstates;
}
else
{
while (cache->lru_superstate->locks)
{
cache->lru_superstate = cache->lru_superstate->next_recyclable;
++locked_superstates;
if (locked_superstates == cache->superstates)
return 0;
}
it = cache->lru_superstate;
it->next_recyclable->prev_recyclable = it->prev_recyclable;
it->prev_recyclable->next_recyclable = it->next_recyclable;
cache->lru_superstate = ((it == it->next_recyclable)
? 0
: it->next_recyclable);
}
if (it->transition_refs)
{
struct rx_distinct_future *df;
for (df = it->transition_refs,
df->prev_same_dest->next_same_dest = 0;
df;
df = df->next_same_dest)
{
df->future_frame.inx = cache->instruction_table[rx_cache_miss];
df->future_frame.data = 0;
df->future_frame.data_2 = (void *) df;
df->future = 0;
}
it->transition_refs->prev_same_dest->next_same_dest =
it->transition_refs;
}
{
struct rx_super_edge *tc = it->edges;
while (tc)
{
struct rx_distinct_future * df;
struct rx_super_edge *tct = tc->next;
df = tc->options;
df->next_same_super_edge[1]->next_same_super_edge[0] = 0;
while (df)
{
struct rx_distinct_future *dft = df;
df = df->next_same_super_edge[0];
if (dft->future && dft->future->transition_refs == dft)
{
dft->future->transition_refs = dft->next_same_dest;
if (dft->future->transition_refs == dft)
dft->future->transition_refs = 0;
}
dft->next_same_dest->prev_same_dest = dft->prev_same_dest;
dft->prev_same_dest->next_same_dest = dft->next_same_dest;
rx_cache_free (cache, &cache->free_discernable_futures,
(char *)dft);
}
rx_cache_free (cache, &cache->free_transition_classes, (char *)tc);
tc = tct;
}
}
if (it->contents->superstate == it)
it->contents->superstate = 0;
release_superset_low (cache, it->contents);
rx_cache_free (cache, &cache->free_superstates, (char *)it);
--cache->superstates;
return 1;
}
#ifdef __STDC__
static char *
rx_cache_get (struct rx_cache * cache,
struct rx_freelist ** freelist)
#else
static char *
rx_cache_get (cache, freelist)
struct rx_cache * cache;
struct rx_freelist ** freelist;
#endif
{
while (!*freelist && rx_really_free_superstate (cache))
;
if (!*freelist)
return 0;
{
struct rx_freelist * it = *freelist;
*freelist = it->next;
return (char *)it;
}
}
#ifdef __STDC__
static char *
rx_cache_malloc_or_get (struct rx_cache * cache,
struct rx_freelist ** freelist, int bytes)
#else
static char *
rx_cache_malloc_or_get (cache, freelist, bytes)
struct rx_cache * cache;
struct rx_freelist ** freelist;
int bytes;
#endif
{
if (!*freelist)
{
char * answer = rx_cache_malloc (cache, bytes);
if (answer)
return answer;
}
return rx_cache_get (cache, freelist);
}
#ifdef __STDC__
static char *
rx_cache_get_superstate (struct rx_cache * cache)
#else
static char *
rx_cache_get_superstate (cache)
struct rx_cache * cache;
#endif
{
char * answer;
int bytes = ( sizeof (struct rx_superstate)
+ cache->local_cset_size * sizeof (struct rx_inx));
if (!cache->free_superstates
&& (cache->superstates < cache->superstates_allowed))
{
answer = rx_cache_malloc (cache, bytes);
if (answer)
{
++cache->superstates;
return answer;
}
}
answer = rx_cache_get (cache, &cache->free_superstates);
if (!answer)
{
answer = rx_cache_malloc (cache, bytes);
if (answer)
++cache->superstates_allowed;
}
++cache->superstates;
return answer;
}
#ifdef __STDC__
static int
supersetcmp (void * va, void * vb)
#else
static int
supersetcmp (va, vb)
void * va;
void * vb;
#endif
{
struct rx_superset * a = (struct rx_superset *)va;
struct rx_superset * b = (struct rx_superset *)vb;
return ( (a == b)
|| (a && b && (a->car == b->car) && (a->cdr == b->cdr)));
}
#ifdef __STDC__
static struct rx_hash_item *
superset_allocator (struct rx_hash_rules * rules, void * val)
#else
static struct rx_hash_item *
superset_allocator (rules, val)
struct rx_hash_rules * rules;
void * val;
#endif
{
struct rx_cache * cache
= ((struct rx_cache *)
((char *)rules
- (unsigned long)(&((struct rx_cache *)0)->superset_hash_rules)));
struct rx_superset * template = (struct rx_superset *)val;
struct rx_superset * newset
= ((struct rx_superset *)
rx_cache_malloc_or_get (cache,
&cache->free_supersets,
sizeof (*template)));
if (!newset)
return 0;
newset->refs = 0;
newset->car = template->car;
newset->id = template->car->id;
newset->cdr = template->cdr;
newset->superstate = 0;
rx_protect_superset (rx, template->cdr);
newset->hash_item.data = (void *)newset;
newset->hash_item.binding = 0;
return &newset->hash_item;
}
#ifdef __STDC__
static struct rx_hash *
super_hash_allocator (struct rx_hash_rules * rules)
#else
static struct rx_hash *
super_hash_allocator (rules)
struct rx_hash_rules * rules;
#endif
{
struct rx_cache * cache
= ((struct rx_cache *)
((char *)rules
- (unsigned long)(&((struct rx_cache *)0)->superset_hash_rules)));
return ((struct rx_hash *)
rx_cache_malloc_or_get (cache,
&cache->free_hash, sizeof (struct rx_hash)));
}
#ifdef __STDC__
static void
super_hash_liberator (struct rx_hash * hash, struct rx_hash_rules * rules)
#else
static void
super_hash_liberator (hash, rules)
struct rx_hash * hash;
struct rx_hash_rules * rules;
#endif
{
struct rx_cache * cache
= ((struct rx_cache *)
(char *)rules - (long)(&((struct rx_cache *)0)->superset_hash_rules));
rx_cache_free (cache, &cache->free_hash, (char *)hash);
}
#ifdef __STDC__
static void
superset_hash_item_liberator (struct rx_hash_item * it,
struct rx_hash_rules * rules)
#else
static void
superset_hash_item_liberator (it, rules) /* Well, it does ya know. */
struct rx_hash_item * it;
struct rx_hash_rules * rules;
#endif
{
}
int rx_cache_bound = 128;
static int rx_default_cache_got = 0;
#ifdef __STDC__
static int
bytes_for_cache_size (int supers, int cset_size)
#else
static int
bytes_for_cache_size (supers, cset_size)
int supers;
int cset_size;
#endif
{
/* What the hell is this? !!!*/
return (int)
((float)supers *
( (1.03 * (float) ( rx_sizeof_bitset (cset_size)
+ sizeof (struct rx_super_edge)))
+ (1.80 * (float) sizeof (struct rx_possible_future))
+ (float) ( sizeof (struct rx_superstate)
+ cset_size * sizeof (struct rx_inx))));
}
#ifdef __STDC__
static void
rx_morecore (struct rx_cache * cache)
#else
static void
rx_morecore (cache)
struct rx_cache * cache;
#endif
{
if (rx_default_cache_got >= rx_cache_bound)
return;
rx_default_cache_got += 16;
cache->superstates_allowed = rx_cache_bound;
{
struct rx_blocklist ** pos = &cache->memory;
int size = bytes_for_cache_size (16, cache->local_cset_size);
while (*pos)
pos = &(*pos)->next;
*pos = ((struct rx_blocklist *)
malloc (size + sizeof (struct rx_blocklist)));
if (!*pos)
return;
(*pos)->next = 0;
(*pos)->bytes = size;
cache->memory_pos = *pos;
cache->memory_addr = (char *)*pos + sizeof (**pos);
cache->bytes_left = size;
}
}
static struct rx_cache default_cache =
{
{
supersetcmp,
super_hash_allocator,
super_hash_liberator,
superset_allocator,
superset_hash_item_liberator,
},
0,
0,
0,
0,
rx_morecore,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
128,
256,
rx_id_instruction_table,
{
0,
0,
{0},
{0},
{0}
}
};
/* This adds an element to a superstate set. These sets are lists, such
* that lists with == elements are ==. The empty set is returned by
* superset_cons (rx, 0, 0) and is NOT equivelent to
* (struct rx_superset)0.
*/
#ifdef __STDC__
RX_DECL struct rx_superset *
rx_superset_cons (struct rx * rx,
struct rx_nfa_state *car, struct rx_superset *cdr)
#else
RX_DECL struct rx_superset *
rx_superset_cons (rx, car, cdr)
struct rx * rx;
struct rx_nfa_state *car;
struct rx_superset *cdr;
#endif
{
struct rx_cache * cache = rx->cache;
if (!car && !cdr)
{
if (!cache->empty_superset)
{
cache->empty_superset
= ((struct rx_superset *)
rx_cache_malloc_or_get (cache, &cache->free_supersets,
sizeof (struct rx_superset)));
if (!cache->empty_superset)
return 0;
bzero (cache->empty_superset, sizeof (struct rx_superset));
cache->empty_superset->refs = 1000;
}
return cache->empty_superset;
}
{
struct rx_superset template;
struct rx_hash_item * hit;
template.car = car;
template.cdr = cdr;
template.id = car->id;
hit = rx_hash_store (&cache->superset_table,
(unsigned long)car ^ car->id ^ (unsigned long)cdr,
(void *)&template,
&cache->superset_hash_rules);
return (hit
? (struct rx_superset *)hit->data
: 0);
}
}
/* This computes a union of two NFA state sets. The sets do not have the
* same representation though. One is a RX_SUPERSET structure (part
* of the superstate NFA) and the other is an NFA_STATE_SET (part of the NFA).
*/
#ifdef __STDC__
RX_DECL struct rx_superset *
rx_superstate_eclosure_union
(struct rx * rx, struct rx_superset *set, struct rx_nfa_state_set *ecl)
#else
RX_DECL struct rx_superset *
rx_superstate_eclosure_union (rx, set, ecl)
struct rx * rx;
struct rx_superset *set;
struct rx_nfa_state_set *ecl;
#endif
{
if (!ecl)
return set;
if (!set->car)
return rx_superset_cons (rx, ecl->car,
rx_superstate_eclosure_union (rx, set, ecl->cdr));
if (set->car == ecl->car)
return rx_superstate_eclosure_union (rx, set, ecl->cdr);
{
struct rx_superset * tail;
struct rx_nfa_state * first;
if (set->car > ecl->car)
{
tail = rx_superstate_eclosure_union (rx, set->cdr, ecl);
first = set->car;
}
else
{
tail = rx_superstate_eclosure_union (rx, set, ecl->cdr);
first = ecl->car;
}
if (!tail)
return 0;
else
{
struct rx_superset * answer;
answer = rx_superset_cons (rx, first, tail);
if (!answer)
{
rx_protect_superset (rx, tail);
rx_release_superset (rx, tail);
return 0;
}
else
return answer;
}
}
}
/*
* This makes sure that a list of rx_distinct_futures contains
* a future for each possible set of side effects in the eclosure
* of a given state. This is some of the work of filling in a
* superstate transition.
*/
#ifdef __STDC__
static struct rx_distinct_future *
include_futures (struct rx *rx,
struct rx_distinct_future *df, struct rx_nfa_state
*state, struct rx_superstate *superstate)
#else
static struct rx_distinct_future *
include_futures (rx, df, state, superstate)
struct rx *rx;
struct rx_distinct_future *df;
struct rx_nfa_state *state;
struct rx_superstate *superstate;
#endif
{
struct rx_possible_future *future;
struct rx_cache * cache = rx->cache;
for (future = state->futures; future; future = future->next)
{
struct rx_distinct_future *dfp;
struct rx_distinct_future *insert_before = 0;
if (df)
df->next_same_super_edge[1]->next_same_super_edge[0] = 0;
for (dfp = df; dfp; dfp = dfp->next_same_super_edge[0])
if (dfp->effects == future->effects)
break;
else
{
int order = rx->se_list_cmp (rx, dfp->effects, future->effects);
if (order > 0)
{
insert_before = dfp;
dfp = 0;
break;
}
}
if (df)
df->next_same_super_edge[1]->next_same_super_edge[0] = df;
if (!dfp)
{
dfp
= ((struct rx_distinct_future *)
rx_cache_malloc_or_get (cache, &cache->free_discernable_futures,
sizeof (struct rx_distinct_future)));
if (!dfp)
return 0;
if (!df)
{
df = insert_before = dfp;
df->next_same_super_edge[0] = df->next_same_super_edge[1] = df;
}
else if (!insert_before)
insert_before = df;
else if (insert_before == df)
df = dfp;
dfp->next_same_super_edge[0] = insert_before;
dfp->next_same_super_edge[1]
= insert_before->next_same_super_edge[1];
dfp->next_same_super_edge[1]->next_same_super_edge[0] = dfp;
dfp->next_same_super_edge[0]->next_same_super_edge[1] = dfp;
dfp->next_same_dest = dfp->prev_same_dest = dfp;
dfp->future = 0;
dfp->present = superstate;
dfp->future_frame.inx = rx->instruction_table[rx_cache_miss];
dfp->future_frame.data = 0;
dfp->future_frame.data_2 = (void *) dfp;
dfp->side_effects_frame.inx
= rx->instruction_table[rx_do_side_effects];
dfp->side_effects_frame.data = 0;
dfp->side_effects_frame.data_2 = (void *) dfp;
dfp->effects = future->effects;
}
}
return df;
}
/* This constructs a new superstate from its state set. The only
* complexity here is memory management.
*/
#ifdef __STDC__
RX_DECL struct rx_superstate *
rx_superstate (struct rx *rx,
struct rx_superset *set)
#else
RX_DECL struct rx_superstate *
rx_superstate (rx, set)
struct rx *rx;
struct rx_superset *set;
#endif
{
struct rx_cache * cache = rx->cache;
struct rx_superstate * superstate = 0;
/* Does the superstate already exist in the cache? */
if (set->superstate)
{
if (set->superstate->rx_id != rx->rx_id)
{
/* Aha. It is in the cache, but belongs to a superstate
* that refers to an NFA that no longer exists.
* (We know it no longer exists because it was evidently
* stored in the same region of memory as the current nfa
* yet it has a different id.)
*/
superstate = set->superstate;
if (!superstate->is_semifree)
{
if (cache->lru_superstate == superstate)
{
cache->lru_superstate = superstate->next_recyclable;
if (cache->lru_superstate == superstate)
cache->lru_superstate = 0;
}
{
superstate->next_recyclable->prev_recyclable
= superstate->prev_recyclable;
superstate->prev_recyclable->next_recyclable
= superstate->next_recyclable;
if (!cache->semifree_superstate)
{
(cache->semifree_superstate
= superstate->next_recyclable
= superstate->prev_recyclable
= superstate);
}
else
{
superstate->next_recyclable = cache->semifree_superstate;
superstate->prev_recyclable
= cache->semifree_superstate->prev_recyclable;
superstate->next_recyclable->prev_recyclable
= superstate;
superstate->prev_recyclable->next_recyclable
= superstate;
cache->semifree_superstate = superstate;
}
++cache->semifree_superstates;
}
}
set->superstate = 0;
goto handle_cache_miss;
}
++cache->hits;
superstate = set->superstate;
rx_refresh_this_superstate (cache, superstate);
return superstate;
}
handle_cache_miss:
/* This point reached only for cache misses. */
++cache->misses;
#if RX_DEBUG
if (rx_debug_trace > 1)
{
struct rx_superset * setp = set;
fprintf (stderr, "Building a superstet %d(%d): ", rx->rx_id, set);
while (setp)
{
fprintf (stderr, "%d ", setp->id);
setp = setp->cdr;
}
fprintf (stderr, "(%d)n", set);
}
#endif
superstate = (struct rx_superstate *)rx_cache_get_superstate (cache);
if (!superstate)
return 0;
if (!cache->lru_superstate)
(cache->lru_superstate
= superstate->next_recyclable
= superstate->prev_recyclable
= superstate);
else
{
superstate->next_recyclable = cache->lru_superstate;
superstate->prev_recyclable = cache->lru_superstate->prev_recyclable;
( superstate->prev_recyclable->next_recyclable
= superstate->next_recyclable->prev_recyclable
= superstate);
}
superstate->rx_id = rx->rx_id;
superstate->transition_refs = 0;
superstate->locks = 0;
superstate->is_semifree = 0;
set->superstate = superstate;
superstate->contents = set;
rx_protect_superset (rx, set);
superstate->edges = 0;
{
int x;
/* None of the transitions from this superstate are known yet. */
for (x = 0; x < rx->local_cset_size; ++x) /* &&&&& 3.8 % */
{
struct rx_inx * ifr = &superstate->transitions[x];
ifr->inx = rx->instruction_table [rx_cache_miss];
ifr->data = ifr->data_2 = 0;
}
}
return superstate;
}
/* This computes the destination set of one edge of the superstate NFA.
* Note that a RX_DISTINCT_FUTURE is a superstate edge.
* Returns 0 on an allocation failure.
*/
#ifdef __STDC__
static int
solve_destination (struct rx *rx, struct rx_distinct_future *df)
#else
static int
solve_destination (rx, df)
struct rx *rx;
struct rx_distinct_future *df;
#endif
{
struct rx_super_edge *tc = df->edge;
struct rx_superset *nfa_state;
struct rx_superset *nil_set = rx_superset_cons (rx, 0, 0);
struct rx_superset *solution = nil_set;
struct rx_superstate *dest;
rx_protect_superset (rx, solution);
/* Iterate over all NFA states in the state set of this superstate. */
for (nfa_state = df->present->contents;
nfa_state->car;
nfa_state = nfa_state->cdr)
{
struct rx_nfa_edge *e;
/* Iterate over all edges of each NFA state. */
for (e = nfa_state->car->edges; e; e = e->next)
/* If we find an edge that is labeled with
* the characters we are solving for.....
*/
if (rx_bitset_is_subset (rx->local_cset_size,
tc->cset, e->params.cset))
{
struct rx_nfa_state *n = e->dest;
struct rx_possible_future *pf;
/* ....search the partial epsilon closures of the destination
* of that edge for a path that involves the same set of
* side effects we are solving for.
* If we find such a RX_POSSIBLE_FUTURE, we add members to the
* stateset we are computing.
*/
for (pf = n->futures; pf; pf = pf->next)
if (pf->effects == df->effects)
{
struct rx_superset * old_sol;
old_sol = solution;
solution = rx_superstate_eclosure_union (rx, solution,
pf->destset);
if (!solution)
return 0;
rx_protect_superset (rx, solution);
rx_release_superset (rx, old_sol);
}
}
}
/* It is possible that the RX_DISTINCT_FUTURE we are working on has
* the empty set of NFA states as its definition. In that case, this
* is a failure point.
*/
if (solution == nil_set)
{
df->future_frame.inx = (void *) rx_backtrack;
df->future_frame.data = 0;
df->future_frame.data_2 = 0;