IP电话/视频会议

开发平台：

Visual C++

regex.cxx：源码内容

/* Extended regular expression matching and search library,
version 0.12.
(Implements POSIX draft P10003.2/D11.2, except for
internationalization features.)
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* AIX requires this to be the first thing in the file. */
#if defined (_AIX) && !defined (REGEX_MALLOC)
#pragma alloca
#endif
/* Technically malloc.h is depricated in most unixes and the malloc
prototypes moved to stdlib.h. Continue to use malloc.h except for
Mac OS X*/
#if !defined(P_MACOSX)
#include <malloc.h>
#endif
#define alloca _alloca
#define _GNU_SOURCE
/* We need this for `regex.h', and perhaps for the Emacs include files. */
#include <sys/types.h>
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
/* The `emacs' switch turns on certain matching commands
that make sense only in Emacs. */
#ifdef emacs
#include "lisp.h"
#include "buffer.h"
#include "syntax.h"
/* Emacs uses `NULL' as a predicate. */
#undef NULL
#else /* not emacs */
/* We used to test for `BSTRING' here, but only GCC and Emacs define
`BSTRING', as far as I know, and neither of them use this code. */
#if HAVE_STRING_H || STDC_HEADERS
#include <string.h>
#ifndef bcmp
#define bcmp(s1, s2, n) memcmp ((s1), (s2), (n))
#endif
#ifndef bcopy
#define bcopy(s, d, n) memcpy ((d), (s), (n))
#endif
#ifndef bzero
#define bzero(s, n) memset ((s), 0, (n))
#endif
#else
#include <strings.h>
#endif
#ifdef STDC_HEADERS
#include <stdlib.h>
#else
char *malloc ();
char *realloc ();
#endif
#ifdef __NUCLEUS_PLUS__
#define REGEX_MALLOC malloc
#endif
/* Define the syntax stuff for <, >, etc. */
/* This must be nonzero for the wordchar and notwordchar pattern
commands in re_match_2. */
#ifndef Sword
#define Sword 1
#endif
#ifdef SYNTAX_TABLE
extern char *re_syntax_table;
#else /* not SYNTAX_TABLE */
/* How many characters in the character set. */
#define CHAR_SET_SIZE 256
static char re_syntax_table[CHAR_SET_SIZE];
static void
init_syntax_once ()
{
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 */
#define SYNTAX(c) re_syntax_table[c]
#endif /* not emacs */
/* Get the interface, including the syntax bits. */
#include "regex.h"
/* isalpha etc. are used for the character classes. */
#include <ctype.h>
#ifndef isascii
#define isascii(c) 1
#endif
#ifdef isblank
#define ISBLANK(c) (isascii (c) && isblank (c))
#else
#define ISBLANK(c) ((c) == ' ' || (c) == 't')
#endif
#ifdef isgraph
#define ISGRAPH(c) (isascii (c) && isgraph (c))
#else
#define ISGRAPH(c) (isascii (c) && isprint (c) && !isspace (c))
#endif
#define ISPRINT(c) (isascii (c) && isprint (c))
#define ISDIGIT(c) (isascii (c) && isdigit (c))
#define ISALNUM(c) (isascii (c) && isalnum (c))
#define ISALPHA(c) (isascii (c) && isalpha (c))
#define ISCNTRL(c) (isascii (c) && iscntrl (c))
#define ISLOWER(c) (isascii (c) && islower (c))
#define ISPUNCT(c) (isascii (c) && ispunct (c))
#define ISSPACE(c) (isascii (c) && isspace (c))
#define ISUPPER(c) (isascii (c) && isupper (c))
#define ISXDIGIT(c) (isascii (c) && isxdigit (c))
#ifndef NULL
#define NULL 0
#endif
/* We remove any previous definition of `SIGN_EXTEND_CHAR',
since ours (we hope) works properly with all combinations of
machines, compilers, `char' and `unsigned char' argument types.
(Per Bothner suggested the basic approach.) */
#undef SIGN_EXTEND_CHAR
#if __STDC__
#define SIGN_EXTEND_CHAR(c) ((signed char) (c))
#else /* not __STDC__ */
/* As in Harbison and Steele. */
#define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
#endif
/* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
use `alloca' instead of `malloc'. This is because using malloc in
re_search* or re_match* could cause memory leaks when C-g is used in
Emacs; also, malloc is slower and causes storage fragmentation. On
the other hand, malloc is more portable, and easier to debug.
Because we sometimes use alloca, some routines have to be macros,
not functions -- `alloca'-allocated space disappears at the end of the
function it is called in. */
#ifdef REGEX_MALLOC
#define REGEX_ALLOCATE malloc
#define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
#else /* not REGEX_MALLOC */
/* 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 */
#define REGEX_ALLOCATE alloca
/* Assumes a `char *destination' variable. */
#define REGEX_REALLOCATE(source, osize, nsize)
(destination = (char *) alloca (nsize),
bcopy (source, destination, osize),
destination)
#endif /* not REGEX_MALLOC */
/* True if `size1' is non-NULL and PTR is pointing anywhere inside
`string1' or just past its end. This works if PTR is NULL, which is
a good thing. */
#define FIRST_STRING_P(ptr)
(size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
/* (Re)Allocate N items of type T using malloc, or fail. */
#define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
#define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
#define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
#define BYTEWIDTH 8 /* In bits. */
#define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
#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
/* These are the command codes that appear in compiled regular
expressions. Some opcodes are followed by argument bytes. A
command code can specify any interpretation whatsoever for its
arguments. Zero bytes may appear in the compiled regular expression.
The value of `exactn' is needed in search.c (search_buffer) in Emacs.
So regex.h defines a symbol `RE_EXACTN_VALUE' to be 1; the value of
`exactn' we use here must also be 1. */
typedef enum
{
no_op = 0,
/* Followed by one byte giving n, then by n literal bytes. */
exactn = 1,
/* Matches any (more or less) character. */
anychar,
/* Matches any one char belonging to specified set. First
following byte is number of bitmap bytes. Then come bytes
for a bitmap saying which chars are in. Bits in each byte
are ordered low-bit-first. A character is in the set if its
bit is 1. A character too large to have a bit in the map is
automatically not in the set. */
charset,
/* Same parameters as charset, but match any character that is
not one of those specified. */
charset_not,
/* Start remembering the text that is matched, for storing in a
register. Followed by one byte with the register number, in
the range 0 to one less than the pattern buffer's re_nsub
field. Then followed by one byte with the number of groups
inner to this one. (This last has to be part of the
start_memory only because we need it in the on_failure_jump
of re_match_2.) */
start_memory,
/* Stop remembering the text that is matched and store it in a
memory register. Followed by one byte with the register
number, in the range 0 to one less than `re_nsub' in the
pattern buffer, and one byte with the number of inner groups,
just like `start_memory'. (We need the number of inner
groups here because we don't have any easy way of finding the
corresponding start_memory when we're at a stop_memory.) */
stop_memory,
/* Match a duplicate of something remembered. Followed by one
byte containing the register number. */
duplicate,
/* Fail unless at beginning of line. */
begline,
/* Fail unless at end of line. */
endline,
/* Succeeds if at beginning of buffer (if emacs) or at beginning
of string to be matched (if not). */
begbuf,
/* Analogously, for end of buffer/string. */
endbuf,
/* Followed by two byte relative address to which to jump. */
jump,
/* Same as jump, but marks the end of an alternative. */
jump_past_alt,
/* Followed by two-byte relative address of place to resume at
in case of failure. */
on_failure_jump,
/* Like on_failure_jump, but pushes a placeholder instead of the
current string position when executed. */
on_failure_keep_string_jump,
/* Throw away latest failure point and then jump to following
two-byte relative address. */
pop_failure_jump,
/* Change to pop_failure_jump if know won't have to backtrack to
match; otherwise change to jump. This is used to jump
back to the beginning of a repeat. If what follows this jump
clearly won't match what the repeat does, such that we can be
sure that there is no use backtracking out of repetitions
already matched, then we change it to a pop_failure_jump.
Followed by two-byte address. */
maybe_pop_jump,
/* Jump to following two-byte address, and push a dummy failure
point. This failure point will be thrown away if an attempt
is made to use it for a failure. A `+' construct makes this
before the first repeat. Also used as an intermediary kind
of jump when compiling an alternative. */
dummy_failure_jump,
/* Push a dummy failure point and continue. Used at the end of
alternatives. */
push_dummy_failure,
/* Followed by two-byte relative address and two-byte number n.
After matching N times, jump to the address upon failure. */
succeed_n,
/* Followed by two-byte relative address, and two-byte number n.
Jump to the address N times, then fail. */
jump_n,
/* Set the following two-byte relative address to the
subsequent two-byte number. The address *includes* the two
bytes of number. */
set_number_at,
wordchar, /* Matches any word-constituent character. */
notwordchar, /* Matches any char that is not a word-constituent. */
wordbeg, /* Succeeds if at word beginning. */
wordend, /* Succeeds if at word end. */
wordbound, /* Succeeds if at a word boundary. */
notwordbound /* Succeeds if not at a word boundary. */
#ifdef emacs
,before_dot, /* Succeeds if before point. */
at_dot, /* Succeeds if at point. */
after_dot, /* Succeeds if after point. */
/* Matches any character whose syntax is specified. Followed by
a byte which contains a syntax code, e.g., Sword. */
syntaxspec,
/* Matches any character whose syntax is not that specified. */
notsyntaxspec
#endif /* emacs */
} re_opcode_t;
/* Common operations on the compiled pattern. */
/* Store NUMBER in two contiguous bytes starting at DESTINATION. */
#define STORE_NUMBER(destination, number)
do {
(destination)[0] = (number) & 0377;
(destination)[1] = (number) >> 8;
} while (0)
/* Same as STORE_NUMBER, except increment DESTINATION to
the byte after where the number is stored. Therefore, DESTINATION
must be an lvalue. */
#define STORE_NUMBER_AND_INCR(destination, number)
do {
STORE_NUMBER (destination, number);
(destination) += 2;
} while (0)
/* Put into DESTINATION a number stored in two contiguous bytes starting
at SOURCE. */
#define EXTRACT_NUMBER(destination, source)
do {
(destination) = *(source) & 0377;
(destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8;
} while (0)
#ifdef DEBUG
static void
extract_number (dest, source)
int *dest;
unsigned char *source;
{
int temp = SIGN_EXTEND_CHAR (*(source + 1));
*dest = *source & 0377;
*dest += temp << 8;
}
#ifndef EXTRACT_MACROS /* To debug the macros. */
#undef EXTRACT_NUMBER
#define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
#endif /* not EXTRACT_MACROS */
#endif /* DEBUG */
/* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
SOURCE must be an lvalue. */
#define EXTRACT_NUMBER_AND_INCR(destination, source)
do {
EXTRACT_NUMBER (destination, source);
(source) += 2;
} while (0)
#ifdef DEBUG
static void
extract_number_and_incr (destination, source)
int *destination;
unsigned char **source;
{
extract_number (destination, *source);
*source += 2;
}
#ifndef EXTRACT_MACROS
#undef EXTRACT_NUMBER_AND_INCR
#define EXTRACT_NUMBER_AND_INCR(dest, src)
extract_number_and_incr (&dest, &src)
#endif /* not EXTRACT_MACROS */
#endif /* DEBUG */
/* If DEBUG is defined, Regex prints many voluminous messages about what
it is doing (if the variable `debug' is nonzero). If linked with the
main program in `iregex.c', you can enter patterns and strings
interactively. And if linked with the main program in `main.c' and
the other test files, you can run the already-written tests. */
#ifdef DEBUG
/* We use standard I/O for debugging. */
#include <stdio.h>
/* It is useful to test things that ``must'' be true when debugging. */
#include <assert.h>
static int debug = 0;
#define DEBUG_STATEMENT(e) e
#define DEBUG_PRINT1(x) if (debug) printf (x)
#define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
#define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
#define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
#define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
if (debug) print_partial_compiled_pattern (s, e)
#define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
if (debug) print_double_string (w, s1, sz1, s2, sz2)
extern void printchar ();
/* Print the fastmap in human-readable form. */
void
print_fastmap (fastmap)
char *fastmap;
{
unsigned was_a_range = 0;
unsigned i = 0;
while (i < (1 << BYTEWIDTH))
{
if (fastmap[i++])
{
was_a_range = 0;
printchar (i - 1);
while (i < (1 << BYTEWIDTH) && fastmap[i])
{
was_a_range = 1;
i++;
}
if (was_a_range)
{
printf ("-");
printchar (i - 1);
}
}
}
putchar ('n');
}
/* Print a compiled pattern string in human-readable form, starting at
the START pointer into it and ending just before the pointer END. */
void
print_partial_compiled_pattern (start, end)
unsigned char *start;
unsigned char *end;
{
int mcnt, mcnt2;
unsigned char *p = start;
unsigned char *pend = end;
if (start == NULL)
{
printf ("(null)n");
return;
}
/* Loop over pattern commands. */
while (p < pend)
{
switch ((re_opcode_t) *p++)
{
case no_op:
printf ("/no_op");
break;
case exactn:
mcnt = *p++;
printf ("/exactn/%d", mcnt);
do
{
putchar ('/');
printchar (*p++);
}
while (--mcnt);
break;
case start_memory:
mcnt = *p++;
printf ("/start_memory/%d/%d", mcnt, *p++);
break;
case stop_memory:
mcnt = *p++;
printf ("/stop_memory/%d/%d", mcnt, *p++);
break;
case duplicate:
printf ("/duplicate/%d", *p++);
break;
case anychar:
printf ("/anychar");
break;
case charset:
case charset_not:
{
register int c;
printf ("/charset%s",
(re_opcode_t) *(p - 1) == charset_not ? "_not" : "");
assert (p + *p < pend);
for (c = 0; c < *p; c++)
{
unsigned bit;
unsigned char map_byte = p[1 + c];
putchar ('/');
for (bit = 0; bit < BYTEWIDTH; bit++)
if (map_byte & (1 << bit))
printchar (c * BYTEWIDTH + bit);
}
p += 1 + *p;
break;
}
case begline:
printf ("/begline");
break;
case endline:
printf ("/endline");
break;
case on_failure_jump:
extract_number_and_incr (&mcnt, &p);
printf ("/on_failure_jump/0/%d", mcnt);
break;
case on_failure_keep_string_jump:
extract_number_and_incr (&mcnt, &p);
printf ("/on_failure_keep_string_jump/0/%d", mcnt);
break;
case dummy_failure_jump:
extract_number_and_incr (&mcnt, &p);
printf ("/dummy_failure_jump/0/%d", mcnt);
break;
case push_dummy_failure:
printf ("/push_dummy_failure");
break;
case maybe_pop_jump:
extract_number_and_incr (&mcnt, &p);
printf ("/maybe_pop_jump/0/%d", mcnt);
break;
case pop_failure_jump:
extract_number_and_incr (&mcnt, &p);
printf ("/pop_failure_jump/0/%d", mcnt);
break;
case jump_past_alt:
extract_number_and_incr (&mcnt, &p);
printf ("/jump_past_alt/0/%d", mcnt);
break;
case jump:
extract_number_and_incr (&mcnt, &p);
printf ("/jump/0/%d", mcnt);
break;
case succeed_n:
extract_number_and_incr (&mcnt, &p);
extract_number_and_incr (&mcnt2, &p);
printf ("/succeed_n/0/%d/0/%d", mcnt, mcnt2);
break;
case jump_n:
extract_number_and_incr (&mcnt, &p);
extract_number_and_incr (&mcnt2, &p);
printf ("/jump_n/0/%d/0/%d", mcnt, mcnt2);
break;
case set_number_at:
extract_number_and_incr (&mcnt, &p);
extract_number_and_incr (&mcnt2, &p);
printf ("/set_number_at/0/%d/0/%d", mcnt, mcnt2);
break;
case wordbound:
printf ("/wordbound");
break;
case notwordbound:
printf ("/notwordbound");
break;
case wordbeg:
printf ("/wordbeg");
break;
case wordend:
printf ("/wordend");
#ifdef emacs
case before_dot:
printf ("/before_dot");
break;
case at_dot:
printf ("/at_dot");
break;
case after_dot:
printf ("/after_dot");
break;
case syntaxspec:
printf ("/syntaxspec");
mcnt = *p++;
printf ("/%d", mcnt);
break;
case notsyntaxspec:
printf ("/notsyntaxspec");
mcnt = *p++;
printf ("/%d", mcnt);
break;
#endif /* emacs */
case wordchar:
printf ("/wordchar");
break;
case notwordchar:
printf ("/notwordchar");
break;
case begbuf:
printf ("/begbuf");
break;
case endbuf:
printf ("/endbuf");
break;
default:
printf ("?%d", *(p-1));
}
}
printf ("/n");
}
void
print_compiled_pattern (bufp)
struct re_pattern_buffer *bufp;
{
unsigned char *buffer = bufp->buffer;
print_partial_compiled_pattern (buffer, buffer + bufp->used);
printf ("%d bytes used/%d bytes allocated.n", bufp->used, bufp->allocated);
if (bufp->fastmap_accurate && bufp->fastmap)
{
printf ("fastmap: ");
print_fastmap (bufp->fastmap);
}
printf ("re_nsub: %dt", bufp->re_nsub);
printf ("regs_alloc: %dt", bufp->regs_allocated);
printf ("can_be_null: %dt", bufp->can_be_null);
printf ("newline_anchor: %dn", bufp->newline_anchor);
printf ("no_sub: %dt", bufp->no_sub);
printf ("not_bol: %dt", bufp->not_bol);
printf ("not_eol: %dt", bufp->not_eol);
printf ("syntax: %dn", bufp->syntax);
/* Perhaps we should print the translate table? */
}
void
print_double_string (where, string1, size1, string2, size2)
const char *where;
const char *string1;
const char *string2;
int size1;
int size2;
{
unsigned this_char;
if (where == NULL)
printf ("(null)");
else
{
if (FIRST_STRING_P (where))
{
for (this_char = where - string1; this_char < size1; this_char++)
printchar (string1[this_char]);
where = string2;
}
for (this_char = where - string2; this_char < size2; this_char++)
printchar (string2[this_char]);
}
}
#else /* not DEBUG */
#undef assert
#define assert(e)
#define DEBUG_STATEMENT(e)
#define DEBUG_PRINT1(x)
#define DEBUG_PRINT2(x1, x2)
#define DEBUG_PRINT3(x1, x2, x3)
#define DEBUG_PRINT4(x1, x2, x3, x4)
#define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
#define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
#endif /* not DEBUG */
/* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
also be assigned to arbitrarily: each pattern buffer stores its own
syntax, so it can be changed between regex compilations. */
reg_syntax_t re_syntax_options = RE_SYNTAX_EMACS;
/* Specify the precise syntax of regexps for compilation. This provides
for compatibility for various utilities which historically have
different, incompatible syntaxes.
The argument SYNTAX is a bit mask comprised of the various bits
defined in regex.h. We return the old syntax. */
reg_syntax_t
re_set_syntax (reg_syntax_t syntax)
{
reg_syntax_t ret = re_syntax_options;
re_syntax_options = syntax;
return ret;
}
/* This table gives an error message for each of the error codes listed
in regex.h. Obviously the order here has to be same as there. */
static const char *re_error_msg[] =
{ NULL, /* REG_NOERROR */
"No match", /* REG_NOMATCH */
"Invalid regular expression", /* REG_BADPAT */
"Invalid collation character", /* REG_ECOLLATE */
"Invalid character class name", /* REG_ECTYPE */
"Trailing backslash", /* REG_EESCAPE */
"Invalid back reference", /* REG_ESUBREG */
"Unmatched [ or [^", /* REG_EBRACK */
"Unmatched ( or \(", /* REG_EPAREN */
"Unmatched \{", /* REG_EBRACE */
"Invalid content of \{\}", /* REG_BADBR */
"Invalid range end", /* REG_ERANGE */
"Memory exhausted", /* REG_ESPACE */
"Invalid preceding regular expression", /* REG_BADRPT */
"Premature end of regular expression", /* REG_EEND */
"Regular expression too big", /* REG_ESIZE */
"Unmatched ) or \)", /* REG_ERPAREN */
};
/* Since we have one byte reserved for the register number argument to
{start,stop}_memory, the maximum number of groups we can report
things about is what fits in that byte. */
#define MAX_REGNUM 255
/* But patterns can have more than `MAX_REGNUM' registers. We just
ignore the excess. */
typedef unsigned regnum_t;
/* Since offsets can go either forwards or backwards, this type needs to
be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
typedef int pattern_offset_t;
typedef struct
{
pattern_offset_t begalt_offset;
pattern_offset_t fixup_alt_jump;
pattern_offset_t inner_group_offset;
pattern_offset_t laststart_offset;
regnum_t regnum;
} compile_stack_elt_t;
typedef struct
{
compile_stack_elt_t *stack;
unsigned size;
unsigned avail; /* Offset of next open position. */
} compile_stack_type;
/* Subroutine declarations and macros for regex_compile. */
static void store_op1 (
re_opcode_t op,
unsigned char *loc,
int arg), store_op2 (
re_opcode_t op,
unsigned char *loc,
int arg1, int arg2);
static void insert_op1 (
re_opcode_t op,
unsigned char *loc,
int arg,
unsigned char *end), insert_op2 (
re_opcode_t op,
unsigned char *loc,
int arg1, int arg2,
unsigned char *end);
static boolean at_begline_loc_p (
const char *pattern, const char *p,
reg_syntax_t syntax), at_endline_loc_p (
const char *p, const char *pend,
int syntax);
static boolean group_in_compile_stack (
compile_stack_type compile_stack,
regnum_t regnum);
static reg_errcode_t compile_range (
const char **p_ptr, const char *pend,
char *translate,
reg_syntax_t syntax,
unsigned char *b);
/* Fetch the next character in the uncompiled pattern---translating it
if necessary. Also cast from a signed character in the constant
string passed to us by the user to an unsigned char that we can use
as an array index (in, e.g., `translate'). */
#define PATFETCH(c)
do {if (p == pend) return REG_EEND;
c = (unsigned char) *p++;
if (translate) c = translate[c];
} while (0)
/* Fetch the next character in the uncompiled pattern, with no
translation. */
#define PATFETCH_RAW(c)
do {if (p == pend) return REG_EEND;
c = (unsigned char) *p++;
} while (0)
/* Go backwards one character in the pattern. */
#define PATUNFETCH p--
/* If `translate' is non-null, return translate[D], else just D. We
cast the subscript to translate because some data is declared as
`char *', to avoid warnings when a string constant is passed. But
when we use a character as a subscript we must make it unsigned. */
#define TRANSLATE(d) (translate ? translate[(unsigned char) (d)] : (d))
/* Macros for outputting the compiled pattern into `buffer'. */
/* If the buffer isn't allocated when it comes in, use this. */
#define INIT_BUF_SIZE 32
/* Make sure we have at least N more bytes of space in buffer. */
#define GET_BUFFER_SPACE(n)
while (b - bufp->buffer + (n) > bufp->allocated)
EXTEND_BUFFER ()
/* Make sure we have one more byte of buffer space and then add C to it. */
#define BUF_PUSH(c)
do {
GET_BUFFER_SPACE (1);
*b++ = (unsigned char) (c);
} while (0)
/* Ensure we have two more bytes of buffer space and then append C1 and C2. */
#define BUF_PUSH_2(c1, c2)
do {
GET_BUFFER_SPACE (2);
*b++ = (unsigned char) (c1);
*b++ = (unsigned char) (c2);
} while (0)
/* As with BUF_PUSH_2, except for three bytes. */
#define BUF_PUSH_3(c1, c2, c3)
do {
GET_BUFFER_SPACE (3);
*b++ = (unsigned char) (c1);
*b++ = (unsigned char) (c2);
*b++ = (unsigned char) (c3);
} while (0)
/* Store a jump with opcode OP at LOC to location TO. We store a
relative address offset by the three bytes the jump itself occupies. */
#define STORE_JUMP(op, loc, to)
store_op1 (op, loc, (to) - (loc) - 3)
/* Likewise, for a two-argument jump. */
#define STORE_JUMP2(op, loc, to, arg)
store_op2 (op, loc, (to) - (loc) - 3, arg)
/* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
#define INSERT_JUMP(op, loc, to)
insert_op1 (op, loc, (to) - (loc) - 3, b)
/* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
#define INSERT_JUMP2(op, loc, to, arg)
insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
/* This is not an arbitrary limit: the arguments which represent offsets
into the pattern are two bytes long. So if 2^16 bytes turns out to
be too small, many things would have to change. */
#define MAX_BUF_SIZE (1L << 16)
/* Extend the buffer by twice its current size via realloc and
reset the pointers that pointed into the old block to point to the
correct places in the new one. If extending the buffer results in it
being larger than MAX_BUF_SIZE, then flag memory exhausted. */
#define EXTEND_BUFFER()
do {
unsigned char *old_buffer = bufp->buffer;
if (bufp->allocated == MAX_BUF_SIZE)
return REG_ESIZE;
bufp->allocated <<= 1;
if (bufp->allocated > MAX_BUF_SIZE)
bufp->allocated = MAX_BUF_SIZE;
bufp->buffer = (unsigned char *) realloc (bufp->buffer, bufp->allocated);
if (bufp->buffer == NULL)
return REG_ESPACE;
/* If the buffer moved, move all the pointers into it. */
if (old_buffer != bufp->buffer)
{
b = (b - old_buffer) + bufp->buffer;
begalt = (begalt - old_buffer) + bufp->buffer;
if (fixup_alt_jump)
fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;
if (laststart)
laststart = (laststart - old_buffer) + bufp->buffer;
if (pending_exact)
pending_exact = (pending_exact - old_buffer) + bufp->buffer;
}
} while (0)
/* Macros for the compile stack. */
#define INIT_COMPILE_STACK_SIZE 32
#define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
#define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
/* The next available element. */
#define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
/* Set the bit for character C in a list. */
#define SET_LIST_BIT(c)
(b[((unsigned char) (c)) / BYTEWIDTH]
|= 1 << (((unsigned char) c) % BYTEWIDTH))
/* Get the next unsigned number in the uncompiled pattern. */
#define GET_UNSIGNED_NUMBER(num)
{ if (p != pend)
{
PATFETCH (c);
while (ISDIGIT (c))
{
if (num < 0)
num = 0;
num = num * 10 + c - '0';
if (p == pend)
break;
PATFETCH (c);
}
}
}
#define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
#define IS_CHAR_CLASS(string)
(STREQ (string, "alpha") || STREQ (string, "upper")
|| STREQ (string, "lower") || STREQ (string, "digit")
|| STREQ (string, "alnum") || STREQ (string, "xdigit")
|| STREQ (string, "space") || STREQ (string, "print")
|| STREQ (string, "punct") || STREQ (string, "graph")
|| STREQ (string, "cntrl") || STREQ (string, "blank"))
/* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
Returns one of error codes defined in `regex.h', or zero for success.
Assumes the `allocated' (and perhaps `buffer') and `translate'
fields are set in BUFP on entry.
If it succeeds, results are put in BUFP (if it returns an error, the
contents of BUFP are undefined):
`buffer' is the compiled pattern;
`syntax' is set to SYNTAX;
`used' is set to the length of the compiled pattern;
`fastmap_accurate' is zero;
`re_nsub' is the number of subexpressions in PATTERN;
`not_bol' and `not_eol' are zero;
The `fastmap' and `newline_anchor' fields are neither
examined nor set. */
static reg_errcode_t
regex_compile (
const char *pattern,
int size,
reg_syntax_t syntax,
struct re_pattern_buffer *bufp)
{
/* We fetch characters from PATTERN here. Even though PATTERN is
`char *' (i.e., signed), we declare these variables as unsigned, so
they can be reliably used as array indices. */
register unsigned char c, c1;
/* A random tempory spot in PATTERN. */
const char *p1;
/* Points to the end of the buffer, where we should append. */
register unsigned char *b;
/* Keeps track of unclosed groups. */
compile_stack_type compile_stack;
/* Points to the current (ending) position in the pattern. */
const char *p = pattern;
const char *pend = pattern + size;
/* How to translate the characters in the pattern. */
char *translate = bufp->translate;
/* Address of the count-byte of the most recently inserted `exactn'
command. This makes it possible to tell if a new exact-match
character can be added to that command or if the character requires
a new `exactn' command. */
unsigned char *pending_exact = 0;
/* Address of start of the most recently finished expression.
This tells, e.g., postfix * where to find the start of its
operand. Reset at the beginning of groups and alternatives. */
unsigned char *laststart = 0;
/* Address of beginning of regexp, or inside of last group. */
unsigned char *begalt;
/* Place in the uncompiled pattern (i.e., the {) to
which to go back if the interval is invalid. */
const char *beg_interval;
/* Address of the place where a forward jump should go to the end of
the containing expression. Each alternative of an `or' -- except the
last -- ends with a forward jump of this sort. */
unsigned char *fixup_alt_jump = 0;
/* Counts open-groups as they are encountered. Remembered for the
matching close-group on the compile stack, so the same register
number is put in the stop_memory as the start_memory. */
regnum_t regnum = 0;
#ifdef DEBUG
DEBUG_PRINT1 ("nCompiling pattern: ");
if (debug)
{
unsigned debug_count;
for (debug_count = 0; debug_count < size; debug_count++)
printchar (pattern[debug_count]);
putchar ('n');
}
#endif /* DEBUG */
/* Initialize the compile stack. */
compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
if (compile_stack.stack == NULL)
return REG_ESPACE;
compile_stack.size = INIT_COMPILE_STACK_SIZE;
compile_stack.avail = 0;
/* Initialize the pattern buffer. */
bufp->syntax = syntax;
bufp->fastmap_accurate = 0;
bufp->not_bol = bufp->not_eol = 0;
/* Set `used' to zero, so that if we return an error, the pattern
printer (for debugging) will think there's no pattern. We reset it
at the end. */
bufp->used = 0;
/* Always count groups, whether or not bufp->no_sub is set. */
bufp->re_nsub = 0;
#if !defined (emacs) && !defined (SYNTAX_TABLE)
/* Initialize the syntax table. */
init_syntax_once ();
#endif
if (bufp->allocated == 0)
{
if (bufp->buffer)
{ /* If zero allocated, but buffer is non-null, try to realloc
enough space. This loses if buffer's address is bogus, but
that is the user's responsibility. */
RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
}
else
{ /* Caller did not allocate a buffer. Do it for them. */
bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
}
if (!bufp->buffer) return REG_ESPACE;
bufp->allocated = INIT_BUF_SIZE;
}
begalt = b = bufp->buffer;
/* Loop through the uncompiled pattern until we're at the end. */
while (p != pend)
{
PATFETCH (c);
switch (c)
{
case '^':
{
if ( /* If at start of pattern, it's an operator. */
p == pattern + 1
/* If context independent, it's an operator. */
|| syntax & RE_CONTEXT_INDEP_ANCHORS
/* Otherwise, depends on what's come before. */
|| at_begline_loc_p (pattern, p, syntax))
BUF_PUSH (begline);
else
goto normal_char;
}
break;
case '$':
{
if ( /* If at end of pattern, it's an operator. */
p == pend
/* If context independent, it's an operator. */
|| syntax & RE_CONTEXT_INDEP_ANCHORS
/* Otherwise, depends on what's next. */
|| at_endline_loc_p (p, pend, syntax))
BUF_PUSH (endline);
else
goto normal_char;
}
break;
case '+':
case '?':
if ((syntax & RE_BK_PLUS_QM)
|| (syntax & RE_LIMITED_OPS))
goto normal_char;
handle_plus:
case '*':
/* If there is no previous pattern... */
if (!laststart)
{
if (syntax & RE_CONTEXT_INVALID_OPS)
return REG_BADRPT;
else if (!(syntax & RE_CONTEXT_INDEP_OPS))
goto normal_char;
}
{
/* Are we optimizing this jump? */
boolean keep_string_p = false;
/* 1 means zero (many) matches is allowed. */
char zero_times_ok = 0, many_times_ok = 0;
/* If there is a sequence of repetition chars, collapse it
down to just one (the right one). We can't combine
interval operators with these because of, e.g., `a{2}*',
which should only match an even number of `a's. */
for (;;)
{
zero_times_ok |= c != '+';
many_times_ok |= c != '?';
if (p == pend)
break;
PATFETCH (c);
if (c == '*'
|| (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?')))
;
else if (syntax & RE_BK_PLUS_QM && c == '\')
{
if (p == pend) return REG_EESCAPE;
PATFETCH (c1);
if (!(c1 == '+' || c1 == '?'))
{
PATUNFETCH;
PATUNFETCH;
break;
}
c = c1;
}
else
{
PATUNFETCH;
break;
}
/* If we get here, we found another repeat character. */
}
/* Star, etc. applied to an empty pattern is equivalent
to an empty pattern. */
if (!laststart)
break;
/* Now we know whether or not zero matches is allowed
and also whether or not two or more matches is allowed. */
if (many_times_ok)
{ /* More than one repetition is allowed, so put in at the
end a backward relative jump from `b' to before the next
jump we're going to put in below (which jumps from
laststart to after this jump).
But if we are at the `*' in the exact sequence `.*n',
insert an unconditional jump backwards to the .,
instead of the beginning of the loop. This way we only
push a failure point once, instead of every time
through the loop. */
assert (p - 1 > pattern);
/* Allocate the space for the jump. */
GET_BUFFER_SPACE (3);
/* We know we are not at the first character of the pattern,
because laststart was nonzero. And we've already
incremented `p', by the way, to be the character after
the `*'. Do we have to do something analogous here
for null bytes, because of RE_DOT_NOT_NULL? */
if (TRANSLATE (*(p - 2)) == TRANSLATE ('.')
&& zero_times_ok
&& p < pend && TRANSLATE (*p) == TRANSLATE ('n')
&& !(syntax & RE_DOT_NEWLINE))
{ /* We have .*n. */
STORE_JUMP (jump, b, laststart);
keep_string_p = true;
}
else
/* Anything else. */
STORE_JUMP (maybe_pop_jump, b, laststart - 3);
/* We've added more stuff to the buffer. */
b += 3;
}
/* On failure, jump from laststart to b + 3, which will be the
end of the buffer after this jump is inserted. */
GET_BUFFER_SPACE (3);
INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump
: on_failure_jump,
laststart, b + 3);
pending_exact = 0;
b += 3;
if (!zero_times_ok)
{
/* At least one repetition is required, so insert a
`dummy_failure_jump' before the initial
`on_failure_jump' instruction of the loop. This
effects a skip over that instruction the first time
we hit that loop. */
GET_BUFFER_SPACE (3);
INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6);
b += 3;
}
}
break;
case '.':
laststart = b;
BUF_PUSH (anychar);
break;
case '[':
{
boolean had_char_class = false;
if (p == pend) return REG_EBRACK;
/* Ensure that we have enough space to push a charset: the
opcode, the length count, and the bitset; 34 bytes in all. */
GET_BUFFER_SPACE (34);
laststart = b;
/* We test `*p == '^' twice, instead of using an if
statement, so we only need one BUF_PUSH. */
BUF_PUSH (*p == '^' ? charset_not : charset);
if (*p == '^')
p++;
/* Remember the first position in the bracket expression. */
p1 = p;
/* Push the number of bytes in the bitmap. */
BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
/* Clear the whole map. */
bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
/* charset_not matches newline according to a syntax bit. */
if ((re_opcode_t) b[-2] == charset_not
&& (syntax & RE_HAT_LISTS_NOT_NEWLINE))
SET_LIST_BIT ('n');
/* Read in characters and ranges, setting map bits. */
for (;;)
{
if (p == pend) return REG_EBRACK;
PATFETCH (c);
/* might escape characters inside [...] and [^...]. */
if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\')
{
if (p == pend) return REG_EESCAPE;
PATFETCH (c1);
SET_LIST_BIT (c1);
continue;
}
/* Could be the end of the bracket expression. If it's
not (i.e., when the bracket expression is `[]' so
far), the ']' character bit gets set way below. */
if (c == ']' && p != p1 + 1)
break;
/* Look ahead to see if it's a range when the last thing
was a character class. */
if (had_char_class && c == '-' && *p != ']')
return REG_ERANGE;
/* Look ahead to see if it's a range when the last thing
was a character: if this is a hyphen not at the
beginning or the end of a list, then it's the range
operator. */
if (c == '-'
&& !(p - 2 >= pattern && p[-2] == '[')
&& !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
&& *p != ']')
{
reg_errcode_t ret
= compile_range (&p, pend, translate, syntax, b);
if (ret != REG_NOERROR) return ret;
}
else if (p[0] == '-' && p[1] != ']')
{ /* This handles ranges made up of characters only. */
reg_errcode_t ret;
/* Move past the `-'. */
PATFETCH (c1);
ret = compile_range (&p, pend, translate, syntax, b);
if (ret != REG_NOERROR) return ret;
}
/* See if we're at the beginning of a possible character
class. */
else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
{ /* Leave room for the null. */
char str[CHAR_CLASS_MAX_LENGTH + 1];
PATFETCH (c);
c1 = 0;
/* If pattern is `[[:'. */
if (p == pend) return REG_EBRACK;
for (;;)
{
PATFETCH (c);
if (c == ':' || c == ']' || p == pend
|| c1 == CHAR_CLASS_MAX_LENGTH)
break;
str[c1++] = c;
}
str[c1] = '';
/* If isn't a word bracketed by `[:' and:`]':
undo the ending character, the letters, and leave
the leading `:' and `[' (but set bits for them). */
if (c == ':' && *p == ']')
{
int ch;
boolean is_alnum = STREQ (str, "alnum");
boolean is_alpha = STREQ (str, "alpha");
boolean is_blank = STREQ (str, "blank");
boolean is_cntrl = STREQ (str, "cntrl");
boolean is_digit = STREQ (str, "digit");
boolean is_graph = STREQ (str, "graph");
boolean is_lower = STREQ (str, "lower");
boolean is_print = STREQ (str, "print");
boolean is_punct = STREQ (str, "punct");
boolean is_space = STREQ (str, "space");
boolean is_upper = STREQ (str, "upper");
boolean is_xdigit = STREQ (str, "xdigit");
if (!IS_CHAR_CLASS (str)) return REG_ECTYPE;
/* Throw away the ] at the end of the character
class. */
PATFETCH (c);
if (p == pend) return REG_EBRACK;
for (ch = 0; ch < 1 << BYTEWIDTH; ch++)
{
if ( (is_alnum && ISALNUM (ch))
|| (is_alpha && ISALPHA (ch))
|| (is_blank && ISBLANK (ch))
|| (is_cntrl && ISCNTRL (ch))
|| (is_digit && ISDIGIT (ch))
|| (is_graph && ISGRAPH (ch))
|| (is_lower && ISLOWER (ch))
|| (is_print && ISPRINT (ch))
|| (is_punct && ISPUNCT (ch))
|| (is_space && ISSPACE (ch))
|| (is_upper && ISUPPER (ch))
|| (is_xdigit && ISXDIGIT (ch)))
SET_LIST_BIT (ch);
}
had_char_class = true;
}
else
{
c1++;
while (c1--)
PATUNFETCH;
SET_LIST_BIT ('[');
SET_LIST_BIT (':');
had_char_class = false;
}
}
else
{
had_char_class = false;
SET_LIST_BIT (c);
}
}
/* Discard any (non)matching list bytes that are all 0 at the
end of the map. Decrease the map-length byte too. */
while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
b[-1]--;
b += b[-1];
}
break;
case '(':
if (syntax & RE_NO_BK_PARENS)
goto handle_open;
else
goto normal_char;
case ')':
if (syntax & RE_NO_BK_PARENS)
goto handle_close;
else
goto normal_char;
case 'n':
if (syntax & RE_NEWLINE_ALT)
goto handle_alt;
else
goto normal_char;
case '|':
if (syntax & RE_NO_BK_VBAR)
goto handle_alt;
else
goto normal_char;
case '{':
if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
goto handle_interval;
else
goto normal_char;
case '\':
if (p == pend) return REG_EESCAPE;
/* Do not translate the character after the , so that we can
distinguish, e.g., B from b, even if we normally would
translate, e.g., B to b. */
PATFETCH_RAW (c);
switch (c)
{
case '(':
if (syntax & RE_NO_BK_PARENS)
goto normal_backslash;
handle_open:
bufp->re_nsub++;
regnum++;
if (COMPILE_STACK_FULL)
{
RETALLOC (compile_stack.stack, compile_stack.size << 1,
compile_stack_elt_t);
if (compile_stack.stack == NULL) return REG_ESPACE;
compile_stack.size <<= 1;
}
/* These are the values to restore when we hit end of this
group. They are all relative offsets, so that if the
whole pattern moves because of realloc, they will still
be valid. */
COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
COMPILE_STACK_TOP.fixup_alt_jump
= fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
COMPILE_STACK_TOP.regnum = regnum;
/* We will eventually replace the 0 with the number of
groups inner to this one. But do not push a
start_memory for groups beyond the last one we can
represent in the compiled pattern. */
if (regnum <= MAX_REGNUM)
{
COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2;
BUF_PUSH_3 (start_memory, regnum, 0);
}
compile_stack.avail++;
fixup_alt_jump = 0;
laststart = 0;
begalt = b;
/* If we've reached MAX_REGNUM groups, then this open
won't actually generate any code, so we'll have to
clear pending_exact explicitly. */
pending_exact = 0;
break;
case ')':
if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
if (COMPILE_STACK_EMPTY)
if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
goto normal_backslash;
else
return REG_ERPAREN;
handle_close:
if (fixup_alt_jump)
{ /* Push a dummy failure point at the end of the
alternative for a possible future
`pop_failure_jump' to pop. See comments at
`push_dummy_failure' in `re_match_2'. */
BUF_PUSH (push_dummy_failure);
/* We allocated space for this jump when we assigned
to `fixup_alt_jump', in the `handle_alt' case below. */
STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1);
}
/* See similar code for backslashed left paren above. */
if (COMPILE_STACK_EMPTY)
if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
goto normal_char;
else
return REG_ERPAREN;
/* Since we just checked for an empty stack above, this
``can't happen''. */
assert (compile_stack.avail != 0);
{
/* We don't just want to restore into `regnum', because
later groups should continue to be numbered higher,
as in `(ab)c(de)' -- the second group is #2. */
regnum_t this_group_regnum;
compile_stack.avail--;
begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
fixup_alt_jump
= COMPILE_STACK_TOP.fixup_alt_jump
? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
: 0;
laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
this_group_regnum = COMPILE_STACK_TOP.regnum;
/* If we've reached MAX_REGNUM groups, then this open
won't actually generate any code, so we'll have to
clear pending_exact explicitly. */
pending_exact = 0;
/* We're at the end of the group, so now we know how many
groups were inside this one. */
if (this_group_regnum <= MAX_REGNUM)
{
unsigned char *inner_group_loc
= bufp->buffer + COMPILE_STACK_TOP.inner_group_offset;
*inner_group_loc = regnum - this_group_regnum;
BUF_PUSH_3 (stop_memory, this_group_regnum,
regnum - this_group_regnum);
}
}
break;
case '|': /* `|'. */
if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
goto normal_backslash;
handle_alt:
if (syntax & RE_LIMITED_OPS)
goto normal_char;
/* Insert before the previous alternative a jump which
jumps to this alternative if the former fails. */
GET_BUFFER_SPACE (3);
INSERT_JUMP (on_failure_jump, begalt, b + 6);
pending_exact = 0;
b += 3;
/* The alternative before this one has a jump after it
which gets executed if it gets matched. Adjust that
jump so it will jump to this alternative's analogous
jump (put in below, which in turn will jump to the next
(if any) alternative's such jump, etc.). The last such
jump jumps to the correct final destination. A picture:
_____ _____
| | | |
| v | v
a | b | c
If we are at `b', then fixup_alt_jump right now points to a
three-byte space after `a'. We'll put in the jump, set
fixup_alt_jump to right after `b', and leave behind three
bytes which we'll fill in when we get to after `c'. */
if (fixup_alt_jump)
STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
/* Mark and leave space for a jump after this alternative,
to be filled in later either by next alternative or
when know we're at the end of a series of alternatives. */
fixup_alt_jump = b;
GET_BUFFER_SPACE (3);
b += 3;
laststart = 0;
begalt = b;
break;
case '{':
/* If { is a literal. */
if (!(syntax & RE_INTERVALS)
/* If we're at `{' and it's not the open-interval
operator. */
|| ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
|| (p - 2 == pattern && p == pend))
goto normal_backslash;
handle_interval:
{
/* If got here, then the syntax allows intervals. */
/* At least (most) this many matches must be made. */
int lower_bound = -1, upper_bound = -1;
beg_interval = p - 1;
if (p == pend)
{
if (syntax & RE_NO_BK_BRACES)
goto unfetch_interval;
else
return REG_EBRACE;
}
GET_UNSIGNED_NUMBER (lower_bound);
if (c == ',')
{
GET_UNSIGNED_NUMBER (upper_bound);
if (upper_bound < 0) upper_bound = RE_DUP_MAX;
}
else
/* Interval such as `{1}' => match exactly once. */
upper_bound = lower_bound;
if (lower_bound < 0 || upper_bound > RE_DUP_MAX
|| lower_bound > upper_bound)
{
if (syntax & RE_NO_BK_BRACES)
goto unfetch_interval;
else
return REG_BADBR;
}
if (!(syntax & RE_NO_BK_BRACES))
{
if (c != '\') return REG_EBRACE;
PATFETCH (c);
}
if (c != '}')
{
if (syntax & RE_NO_BK_BRACES)
goto unfetch_interval;
else
return REG_BADBR;
}
/* We just parsed a valid interval. */
/* If it's invalid to have no preceding re. */
if (!laststart)
{
if (syntax & RE_CONTEXT_INVALID_OPS)
return REG_BADRPT;
else if (syntax & RE_CONTEXT_INDEP_OPS)
laststart = b;
else
goto unfetch_interval;
}
/* If the upper bound is zero, don't want to succeed at
all; jump from `laststart' to `b + 3', which will be
the end of the buffer after we insert the jump. */
if (upper_bound == 0)
{
GET_BUFFER_SPACE (3);
INSERT_JUMP (jump, laststart, b + 3);
b += 3;
}
/* Otherwise, we have a nontrivial interval. When
we're all done, the pattern will look like:
set_number_at <jump count> <upper bound>
set_number_at <succeed_n count> <lower bound>
succeed_n <after jump addr> <succed_n count>
<body of loop>
jump_n <succeed_n addr> <jump count>
(The upper bound and `jump_n' are omitted if
`upper_bound' is 1, though.) */
else
{ /* If the upper bound is > 1, we need to insert
more at the end of the loop. */
unsigned nbytes = 10 + (upper_bound > 1) * 10;
GET_BUFFER_SPACE (nbytes);
/* Initialize lower bound of the `succeed_n', even
though it will be set during matching by its
attendant `set_number_at' (inserted next),
because `re_compile_fastmap' needs to know.
Jump to the `jump_n' we might insert below. */
INSERT_JUMP2 (succeed_n, laststart,
b + 5 + (upper_bound > 1) * 5,
lower_bound);
b += 5;
/* Code to initialize the lower bound. Insert
before the `succeed_n'. The `5' is the last two
bytes of this `set_number_at', plus 3 bytes of
the following `succeed_n'. */
insert_op2 (set_number_at, laststart, 5, lower_bound, b);
b += 5;
if (upper_bound > 1)
{ /* More than one repetition is allowed, so
append a backward jump to the `succeed_n'
that starts this interval.
When we've reached this during matching,
we'll have matched the interval once, so
jump back only `upper_bound - 1' times. */
STORE_JUMP2 (jump_n, b, laststart + 5,
upper_bound - 1);
b += 5;
/* The location we want to set is the second
parameter of the `jump_n'; that is `b-2' as
an absolute address. `laststart' will be
the `set_number_at' we're about to insert;
`laststart+3' the number to set, the source
for the relative address. But we are
inserting into the middle of the pattern --
so everything is getting moved up by 5.
Conclusion: (b - 2) - (laststart + 3) + 5,
i.e., b - laststart.
We insert this at the beginning of the loop
so that if we fail during matching, we'll
reinitialize the bounds. */
insert_op2 (set_number_at, laststart, b - laststart,
upper_bound - 1, b);
b += 5;
}
}
pending_exact = 0;
beg_interval = NULL;
}
break;
unfetch_interval:
/* If an invalid interval, match the characters as literals. */
assert (beg_interval);
p = beg_interval;
beg_interval = NULL;
/* normal_char and normal_backslash need `c'. */
PATFETCH (c);
if (!(syntax & RE_NO_BK_BRACES))
{
if (p > pattern && p[-1] == '\')
goto normal_backslash;
}
goto normal_char;
#ifdef emacs
/* There is no way to specify the before_dot and after_dot
operators. rms says this is ok. --karl */
case '=':
BUF_PUSH (at_dot);
break;
case 's':
laststart = b;
PATFETCH (c);
BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
break;
case 'S':
laststart = b;
PATFETCH (c);
BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
break;
#endif /* emacs */
case 'w':
laststart = b;
BUF_PUSH (wordchar);
break;
case 'W':
laststart = b;
BUF_PUSH (notwordchar);
break;
case '<':
BUF_PUSH (wordbeg);
break;
case '>':
BUF_PUSH (wordend);
break;
case 'b':
BUF_PUSH (wordbound);
break;
case 'B':
BUF_PUSH (notwordbound);
break;
case '`':
BUF_PUSH (begbuf);
break;
case ''':
BUF_PUSH (endbuf);
break;
case '1': case '2': case '3': case '4': case '5':
case '6': case '7': case '8': case '9':
if (syntax & RE_NO_BK_REFS)
goto normal_char;
c1 = c - '0';
if (c1 > regnum)
return REG_ESUBREG;
/* Can't back reference to a subexpression if inside of it. */
if (group_in_compile_stack (compile_stack, c1))
goto normal_char;
laststart = b;
BUF_PUSH_2 (duplicate, c1);
break;
case '+':
case '?':
if (syntax & RE_BK_PLUS_QM)
goto handle_plus;
else
goto normal_backslash;
default:
normal_backslash:
/* You might think it would be useful for to mean
not to translate; but if we don't translate it
it will never match anything. */
c = TRANSLATE (c);
goto normal_char;
}
break;
default:
/* Expects the character in `c'. */
normal_char:
/* If no exactn currently being built. */
if (!pending_exact
/* If last exactn not at current position. */
|| pending_exact + *pending_exact + 1 != b
/* We have only one byte following the exactn for the count. */
|| *pending_exact == (1 << BYTEWIDTH) - 1
/* If followed by a repetition operator. */
|| *p == '*' || *p == '^'
|| ((syntax & RE_BK_PLUS_QM)
? *p == '\' && (p[1] == '+' || p[1] == '?')
: (*p == '+' || *p == '?'))
|| ((syntax & RE_INTERVALS)
&& ((syntax & RE_NO_BK_BRACES)
? *p == '{'
: (p[0] == '\' && p[1] == '{'))))
{
/* Start building a new exactn. */
laststart = b;
BUF_PUSH_2 (exactn, 0);
pending_exact = b - 1;
}
BUF_PUSH (c);
(*pending_exact)++;
break;
} /* switch (c) */
} /* while p != pend */
/* Through the pattern now. */
if (fixup_alt_jump)
STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
if (!COMPILE_STACK_EMPTY)
return REG_EPAREN;
free (compile_stack.stack);
/* We have succeeded; set the length of the buffer. */
bufp->used = b - bufp->buffer;
#ifdef DEBUG
if (debug)
{
DEBUG_PRINT1 ("nCompiled pattern: ");
print_compiled_pattern (bufp);
}
#endif /* DEBUG */
return REG_NOERROR;
} /* regex_compile */
/* Subroutines for `regex_compile'. */
/* Store OP at LOC followed by two-byte integer parameter ARG. */
static void
store_op1 (
re_opcode_t op,
unsigned char *loc,
int arg)
{
*loc = (unsigned char) op;
STORE_NUMBER (loc + 1, arg);
}
/* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
static void
store_op2 (
re_opcode_t op,
unsigned char *loc,
int arg1, int arg2)
{
*loc = (unsigned char) op;
STORE_NUMBER (loc + 1, arg1);
STORE_NUMBER (loc + 3, arg2);
}
/* Copy the bytes from LOC to END to open up three bytes of space at LOC
for OP followed by two-byte integer parameter ARG. */
static void
insert_op1 (
re_opcode_t op,
unsigned char *loc,
int arg,
unsigned char *end)
{
register unsigned char *pfrom = end;
register unsigned char *pto = end + 3;
while (pfrom != loc)
*--pto = *--pfrom;
store_op1 (op, loc, arg);
}
/* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
static void
insert_op2 (
re_opcode_t op,
unsigned char *loc,
int arg1, int arg2,
unsigned char *end)
{
register unsigned char *pfrom = end;
register unsigned char *pto = end + 5;
while (pfrom != loc)
*--pto = *--pfrom;
store_op2 (op, loc, arg1, arg2);
}
/* P points to just after a ^ in PATTERN. Return true if that ^ comes
after an alternative or a begin-subexpression. We assume there is at
least one character before the ^. */
static boolean
at_begline_loc_p (
const char *pattern, const char *p,
reg_syntax_t syntax)
{
const char *prev = p - 2;
boolean prev_prev_backslash = prev > pattern && prev[-1] == '\';
return
/* After a subexpression? */
(*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
/* After an alternative? */
|| (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
}
/* The dual of at_begline_loc_p. This one is for $. We assume there is
at least one character after the $, i.e., `P < PEND'. */
static boolean
at_endline_loc_p (
const char *p, const char *pend,
int syntax)
{
const char *next = p;
boolean next_backslash = *next == '\';
const char *next_next = p + 1 < pend ? p + 1 : NULL;
return
/* Before a subexpression? */
(syntax & RE_NO_BK_PARENS ? *next == ')'
: next_backslash && next_next && *next_next == ')')
/* Before an alternative? */
|| (syntax & RE_NO_BK_VBAR ? *next == '|'
: next_backslash && next_next && *next_next == '|');
}
/* Returns true if REGNUM is in one of COMPILE_STACK's elements and
false if it's not. */
static boolean
group_in_compile_stack (
compile_stack_type compile_stack,
regnum_t regnum)
{
int this_element;
for (this_element = compile_stack.avail - 1;
this_element >= 0;
this_element--)
if (compile_stack.stack[this_element].regnum == regnum)
return true;
return false;
}
/* Read the ending character of a range (in a bracket expression) from the
uncompiled pattern *P_PTR (which ends at PEND). We assume the
starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
Then we set the translation of all bits between the starting and
ending characters (inclusive) in the compiled pattern B.
Return an error code.
We use these short variable names so we can use the same macros as
`regex_compile' itself. */
static reg_errcode_t
compile_range (
const char **p_ptr, const char *pend,
char *translate,
reg_syntax_t syntax,
unsigned char *b)
{
unsigned this_char;
const char *p = *p_ptr;
int range_start, range_end;
if (p == pend)
return REG_ERANGE;
/* Even though the pattern is a signed `char *', we need to fetch
with unsigned char *'s; if the high bit of the pattern character
is set, the range endpoints will be negative if we fetch using a
signed char *.
We also want to fetch the endpoints without translating them; the
appropriate translation is done in the bit-setting loop below. */
range_start = ((unsigned char *) p)[-2];
range_end = ((unsigned char *) p)[0];
/* Have to increment the pointer into the pattern string, so the
caller isn't still at the ending character. */
(*p_ptr)++;
/* If the start is after the end, the range is empty. */
if (range_start > range_end)
return syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
/* Here we see why `this_char' has to be larger than an `unsigned
char' -- the range is inclusive, so if `range_end' == 0xff
(assuming 8-bit characters), we would otherwise go into an infinite
loop, since all characters <= 0xff. */
for (this_char = range_start; this_char <= range_end; this_char++)
{
SET_LIST_BIT (TRANSLATE (this_char));
}
return REG_NOERROR;
}
/* Failure stack declarations and macros; both re_compile_fastmap and
re_match_2 use a failure stack. These have to be macros because of
REGEX_ALLOCATE. */
/* Number of failure points for which to initially allocate space
when matching. If this number is exceeded, we allocate more
space, so it is not a hard limit. */
#ifndef INIT_FAILURE_ALLOC
#define INIT_FAILURE_ALLOC 5
#endif
/* Roughly the maximum number of failure points on the stack. Would be
exactly that if always used MAX_FAILURE_SPACE each time we failed.
This is a variable only so users of regex can assign to it; we never
change it ourselves. */
static int re_max_failures = 2000;
typedef const unsigned char *fail_stack_elt_t;
typedef struct
{
fail_stack_elt_t *stack;
unsigned size;
unsigned avail; /* Offset of next open position. */
} fail_stack_type;
#define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
#define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
#define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
#define FAIL_STACK_TOP() (fail_stack.stack[fail_stack.avail])
/* Initialize `fail_stack'. Do `return -2' if the alloc fails. */
#define INIT_FAIL_STACK()
do {
fail_stack.stack = (fail_stack_elt_t *)
REGEX_ALLOCATE (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t));
if (fail_stack.stack == NULL)
return -2;
fail_stack.size = INIT_FAILURE_ALLOC;
fail_stack.avail = 0;
} while (0)
/* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
Return 1 if succeeds, and 0 if either ran out of memory
allocating space for it or it was already too large.
REGEX_REALLOCATE requires `destination' be declared. */
#define DOUBLE_FAIL_STACK(fail_stack)
((fail_stack).size > re_max_failures * MAX_FAILURE_ITEMS
? 0
: ((fail_stack).stack = (fail_stack_elt_t *)
REGEX_REALLOCATE ((fail_stack).stack,
(fail_stack).size * sizeof (fail_stack_elt_t),
((fail_stack).size << 1) * sizeof (fail_stack_elt_t)),
(fail_stack).stack == NULL
? 0
: ((fail_stack).size <<= 1,
1)))
/* Push PATTERN_OP on FAIL_STACK.
Return 1 if was able to do so and 0 if ran out of memory allocating
space to do so. */
#define PUSH_PATTERN_OP(pattern_op, fail_stack)
((FAIL_STACK_FULL ()
&& !DOUBLE_FAIL_STACK (fail_stack))
? 0
: ((fail_stack).stack[(fail_stack).avail++] = pattern_op,
1))
/* This pushes an item onto the failure stack. Must be a four-byte
value. Assumes the variable `fail_stack'. Probably should only
be called from within `PUSH_FAILURE_POINT'. */
#define PUSH_FAILURE_ITEM(item)
fail_stack.stack[fail_stack.avail++] = (fail_stack_elt_t) item
/* The complement operation. Assumes `fail_stack' is nonempty. */
#define POP_FAILURE_ITEM() fail_stack.stack[--fail_stack.avail]
/* Used to omit pushing failure point id's when we're not debugging. */
#ifdef DEBUG
#define DEBUG_PUSH PUSH_FAILURE_ITEM
#define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_ITEM ()
#else
#define DEBUG_PUSH(item)
#define DEBUG_POP(item_addr)
#endif
/* Push the information about the state we will need
if we ever fail back to it.
Requires variables fail_stack, regstart, regend, reg_info, and
num_regs be declared. DOUBLE_FAIL_STACK requires `destination' be
declared.
Does `return FAILURE_CODE' if runs out of memory. */
#define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code)
do {
char *destination;
/* Must be int, so when we don't save any registers, the arithmetic
of 0 + -1 isn't done as unsigned. */
int this_reg;
DEBUG_STATEMENT (failure_id++);
DEBUG_STATEMENT (nfailure_points_pushed++);
DEBUG_PRINT2 ("nPUSH_FAILURE_POINT #%u:n", failure_id);
DEBUG_PRINT2 (" Before push, next avail: %dn", (fail_stack).avail);
DEBUG_PRINT2 (" size: %dn", (fail_stack).size);
DEBUG_PRINT2 (" slots needed: %dn", NUM_FAILURE_ITEMS);
DEBUG_PRINT2 (" available: %dn", REMAINING_AVAIL_SLOTS);
/* Ensure we have enough space allocated for what we will push. */
while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS)
{
if (!DOUBLE_FAIL_STACK (fail_stack))
return failure_code;
DEBUG_PRINT2 ("n Doubled stack; size now: %dn",
(fail_stack).size);
DEBUG_PRINT2 (" slots available: %dn", REMAINING_AVAIL_SLOTS);
}
/* Push the info, starting with the registers. */
DEBUG_PRINT1 ("n");
for (this_reg = lowest_active_reg; this_reg <= highest_active_reg;
this_reg++)
{
DEBUG_PRINT2 (" Pushing reg: %dn", this_reg);
DEBUG_STATEMENT (num_regs_pushed++);
DEBUG_PRINT2 (" start: 0x%xn", regstart[this_reg]);
PUSH_FAILURE_ITEM (regstart[this_reg]);
DEBUG_PRINT2 (" end: 0x%xn", regend[this_reg]);
PUSH_FAILURE_ITEM (regend[this_reg]);
DEBUG_PRINT2 (" info: 0x%xn ", reg_info[this_reg]);
DEBUG_PRINT2 (" match_null=%d",
REG_MATCH_NULL_STRING_P (reg_info[this_reg]));
DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg]));
DEBUG_PRINT2 (" matched_something=%d",
MATCHED_SOMETHING (reg_info[this_reg]));
DEBUG_PRINT2 (" ever_matched=%d",
EVER_MATCHED_SOMETHING (reg_info[this_reg]));
DEBUG_PRINT1 ("n");
PUSH_FAILURE_ITEM (reg_info[this_reg].word);
}
DEBUG_PRINT2 (" Pushing low active reg: %dn", lowest_active_reg);
PUSH_FAILURE_ITEM (lowest_active_reg);
DEBUG_PRINT2 (" Pushing high active reg: %dn", highest_active_reg);
PUSH_FAILURE_ITEM (highest_active_reg);
DEBUG_PRINT2 (" Pushing pattern 0x%x: ", pattern_place);
DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend);
PUSH_FAILURE_ITEM (pattern_place);
DEBUG_PRINT2 (" Pushing string 0x%x: `", string_place);
DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2,
size2);
DEBUG_PRINT1 ("'n");
PUSH_FAILURE_ITEM (string_place);
DEBUG_PRINT2 (" Pushing failure id: %un", failure_id);
DEBUG_PUSH (failure_id);
} while (0)
/* This is the number of items that are pushed and popped on the stack
for each register. */
#define NUM_REG_ITEMS 3
/* Individual items aside from the registers. */
#ifdef DEBUG
#define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
#else
#define NUM_NONREG_ITEMS 4
#endif
/* We push at most this many items on the stack. */
#define MAX_FAILURE_ITEMS ((num_regs - 1) * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
/* We actually push this many items. */
#define NUM_FAILURE_ITEMS
((highest_active_reg - lowest_active_reg + 1) * NUM_REG_ITEMS
+ NUM_NONREG_ITEMS)
/* How many items can still be added to the stack without overflowing it. */
#define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
/* Pops what PUSH_FAIL_STACK pushes.
We restore into the parameters, all of which should be lvalues:
STR -- the saved data position.
PAT -- the saved pattern position.
LOW_REG, HIGH_REG -- the highest and lowest active registers.
REGSTART, REGEND -- arrays of string positions.
REG_INFO -- array of information about each subexpression.
Also assumes the variables `fail_stack' and (if debugging), `bufp',
`pend', `string1', `size1', `string2', and `size2'. */
#define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)
{