rsalz@uunet.uu.net (Rich Salz) (02/26/91)
Submitted-by: Paul Eggert <eggert@twinsun.com>
Posting-number: Volume 24, Issue 21
Archive-name: gnudiff1.15/part06
#! /bin/sh
# This is a shell archive. Remove anything before this line, then unpack
# it by saving it into a file and typing "sh file". To overwrite existing
# files, type "sh file -c". You can also feed this as standard input via
# unshar, or by typing "sh <file", e.g.. If this archive is complete, you
# will see the following message at the end:
# "End of archive 6 (of 8)."
# Contents: regex.c2
# Wrapped by eggert@ata on Mon Jan 7 11:25:31 1991
PATH=/bin:/usr/bin:/usr/ucb ; export PATH
if test -f 'regex.c2' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'regex.c2'\"
else
echo shar: Extracting \"'regex.c2'\" \(37881 characters\)
sed "s/^X//" >'regex.c2' <<'END_OF_FILE'
X
X
X
X/* Like re_search_2, below, but only one string is specified, and
X doesn't let you say where to stop matching. */
X
Xint
Xre_search (pbufp, string, size, startpos, range, regs)
X struct re_pattern_buffer *pbufp;
X char *string;
X int size, startpos, range;
X struct re_registers *regs;
X{
X return re_search_2 (pbufp, (char *) 0, 0, string, size, startpos, range,
X regs, size);
X}
X
X
X/* Using the compiled pattern in PBUFP->buffer, first tries to match the
X virtual concatenation of STRING1 and STRING2, starting first at index
X STARTPOS, then at STARTPOS + 1, and so on. RANGE is the number of
X places to try before giving up. If RANGE is negative, it searches
X backwards, i.e., the starting positions tried are STARTPOS, STARTPOS
X - 1, etc. STRING1 and STRING2 are of SIZE1 and SIZE2, respectively.
X In REGS, return the indices of the virtual concatenation of STRING1
X and STRING2 that matched the entire PBUFP->buffer and its contained
X subexpressions. Do not consider matching one past the index MSTOP in
X the virtual concatenation of STRING1 and STRING2.
X
X The value returned is the position in the strings at which the match
X was found, or -1 if no match was found, or -2 if error (such as
X failure stack overflow). */
X
Xint
Xre_search_2 (pbufp, string1, size1, string2, size2, startpos, range,
X regs, mstop)
X struct re_pattern_buffer *pbufp;
X char *string1, *string2;
X int size1, size2;
X int startpos;
X register int range;
X struct re_registers *regs;
X int mstop;
X{
X register char *fastmap = pbufp->fastmap;
X register unsigned char *translate = (unsigned char *) pbufp->translate;
X int total_size = size1 + size2;
X int endpos = startpos + range;
X int val;
X
X /* Check for out-of-range starting position. */
X if (startpos < 0 || startpos > total_size)
X return -1;
X
X /* Fix up range if it would eventually take startpos outside of the
X virtual concatenation of string1 and string2. */
X if (endpos < -1)
X range = -1 - startpos;
X else if (endpos > total_size)
X range = total_size - startpos;
X
X /* Update the fastmap now if not correct already. */
X if (fastmap && !pbufp->fastmap_accurate)
X re_compile_fastmap (pbufp);
X
X /* If the search isn't to be a backwards one, don't waste time in a
X long search for a pattern that says it is anchored. */
X if (pbufp->used > 0 && (enum regexpcode) pbufp->buffer[0] == begbuf
X && range > 0)
X {
X if (startpos > 0)
X return -1;
X else
X range = 1;
X }
X
X while (1)
X {
X /* If a fastmap is supplied, skip quickly over characters that
X cannot possibly be the start of a match. Note, however, that
X if the pattern can possibly match the null string, we must
X test it at each starting point so that we take the first null
X string we get. */
X
X if (fastmap && startpos < total_size && pbufp->can_be_null != 1)
X {
X if (range > 0) /* Searching forwards. */
X {
X register int lim = 0;
X register unsigned char *p;
X int irange = range;
X if (startpos < size1 && startpos + range >= size1)
X lim = range - (size1 - startpos);
X
X p = ((unsigned char *)
X &(startpos >= size1 ? string2 - size1 : string1)[startpos]);
X
X while (range > lim && !fastmap[translate
X ? translate[*p++]
X : *p++])
X range--;
X startpos += irange - range;
X }
X else /* Searching backwards. */
X {
X register unsigned char c;
X
X if (string1 == 0 || startpos >= size1)
X c = string2[startpos - size1];
X else
X c = string1[startpos];
X
X c &= 0xff;
X if (translate ? !fastmap[translate[c]] : !fastmap[c])
X goto advance;
X }
X }
X
X if (range >= 0 && startpos == total_size
X && fastmap && pbufp->can_be_null == 0)
X return -1;
X
X val = re_match_2 (pbufp, string1, size1, string2, size2, startpos,
X regs, mstop);
X if (val >= 0)
X return startpos;
X if (val == -2)
X return -2;
X
X#ifdef C_ALLOCA
X alloca (0);
X#endif /* C_ALLOCA */
X
X advance:
X if (!range)
X break;
X else if (range > 0)
X {
X range--;
X startpos++;
X }
X else
X {
X range++;
X startpos--;
X }
X }
X return -1;
X}
X
X
X
X#ifndef emacs /* emacs never uses this. */
Xint
Xre_match (pbufp, string, size, pos, regs)
X struct re_pattern_buffer *pbufp;
X char *string;
X int size, pos;
X struct re_registers *regs;
X{
X return re_match_2 (pbufp, (char *) 0, 0, string, size, pos, regs, size);
X}
X#endif /* not emacs */
X
X
X/* The following are used for re_match_2, defined below: */
X
X/* Roughly the maximum number of failure points on the stack. Would be
X exactly that if always pushed MAX_NUM_FAILURE_ITEMS each time we failed. */
X
Xint re_max_failures = 2000;
X
X/* Routine used by re_match_2. */
Xstatic int bcmp_translate ();
X
X
X/* Structure and accessing macros used in re_match_2: */
X
Xstruct register_info
X{
X unsigned is_active : 1;
X unsigned matched_something : 1;
X};
X
X#define IS_ACTIVE(R) ((R).is_active)
X#define MATCHED_SOMETHING(R) ((R).matched_something)
X
X
X/* Macros used by re_match_2: */
X
X
X/* I.e., regstart, regend, and reg_info. */
X
X#define NUM_REG_ITEMS 3
X
X/* We push at most this many things on the stack whenever we
X fail. The `+ 2' refers to PATTERN_PLACE and STRING_PLACE, which are
X arguments to the PUSH_FAILURE_POINT macro. */
X
X#define MAX_NUM_FAILURE_ITEMS (RE_NREGS * NUM_REG_ITEMS + 2)
X
X
X/* We push this many things on the stack whenever we fail. */
X
X#define NUM_FAILURE_ITEMS (last_used_reg * NUM_REG_ITEMS + 2)
X
X
X/* This pushes most of the information about the current state we will want
X if we ever fail back to it. */
X
X#define PUSH_FAILURE_POINT(pattern_place, string_place) \
X { \
X short last_used_reg, this_reg; \
X \
X /* Find out how many registers are active or have been matched. \
X (Aside from register zero, which is only set at the end.) */ \
X for (last_used_reg = RE_NREGS - 1; last_used_reg > 0; last_used_reg--)\
X if (regstart[last_used_reg] != (unsigned char *) -1) \
X break; \
X \
X if (stacke - stackp < NUM_FAILURE_ITEMS) \
X { \
X unsigned char **stackx; \
X if (stacke - stackb > re_max_failures * MAX_NUM_FAILURE_ITEMS) \
X return -2; \
X \
X /* Roughly double the size of the stack. */ \
X stackx = (unsigned char **) alloca (2 * MAX_NUM_FAILURE_ITEMS \
X * (stacke - stackb) \
X * sizeof (unsigned char *));\
X /* Only copy what is in use. */ \
X bcopy (stackb, stackx, (stackp - stackb) * sizeof (char *)); \
X stackp = stackx + (stackp - stackb); \
X stackb = stackx; \
X stacke = stackb + 2 * MAX_NUM_FAILURE_ITEMS * (stacke - stackb);\
X } \
X \
X /* Now push the info for each of those registers. */ \
X for (this_reg = 1; this_reg <= last_used_reg; this_reg++) \
X { \
X *stackp++ = regstart[this_reg]; \
X *stackp++ = regend[this_reg]; \
X *stackp++ = (unsigned char *) ®_info[this_reg]; \
X } \
X \
X /* Push how many registers we saved. */ \
X *stackp++ = (unsigned char *) last_used_reg; \
X \
X *stackp++ = pattern_place; \
X *stackp++ = string_place; \
X }
X
X
X/* This pops what PUSH_FAILURE_POINT pushes. */
X
X#define POP_FAILURE_POINT() \
X { \
X int temp; \
X stackp -= 2; /* Remove failure points. */ \
X temp = (int) *--stackp; /* How many regs pushed. */ \
X temp *= NUM_REG_ITEMS; /* How much to take off the stack. */ \
X stackp -= temp; /* Remove the register info. */ \
X }
X
X
X#define MATCHING_IN_FIRST_STRING (dend == end_match_1)
X
X/* Is true if there is a first string and if PTR is pointing anywhere
X inside it or just past the end. */
X
X#define IS_IN_FIRST_STRING(ptr) \
X (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
X
X/* Call before fetching a character with *d. This switches over to
X string2 if necessary. */
X
X#define PREFETCH \
X while (d == dend) \
X { \
X /* end of string2 => fail. */ \
X if (dend == end_match_2) \
X goto fail; \
X /* end of string1 => advance to string2. */ \
X d = string2; \
X dend = end_match_2; \
X }
X
X
X/* Call this when have matched something; it sets `matched' flags for the
X registers corresponding to the subexpressions of which we currently
X are inside. */
X#define SET_REGS_MATCHED \
X { unsigned this_reg; \
X for (this_reg = 0; this_reg < RE_NREGS; this_reg++) \
X { \
X if (IS_ACTIVE(reg_info[this_reg])) \
X MATCHED_SOMETHING(reg_info[this_reg]) = 1; \
X else \
X MATCHED_SOMETHING(reg_info[this_reg]) = 0; \
X } \
X }
X
X/* Test if at very beginning or at very end of the virtual concatenation
X of string1 and string2. If there is only one string, we've put it in
X string2. */
X
X#define AT_STRINGS_BEG (d == (size1 ? string1 : string2) || !size2)
X#define AT_STRINGS_END (d == end2)
X
X#define AT_WORD_BOUNDARY \
X (AT_STRINGS_BEG || AT_STRINGS_END || IS_A_LETTER (d - 1) != IS_A_LETTER (d))
X
X/* We have two special cases to check for:
X 1) if we're past the end of string1, we have to look at the first
X character in string2;
X 2) if we're before the beginning of string2, we have to look at the
X last character in string1; we assume there is a string1, so use
X this in conjunction with AT_STRINGS_BEG. */
X#define IS_A_LETTER(d) \
X (SYNTAX ((d) == end1 ? *string2 : (d) == string2 - 1 ? *(end1 - 1) : *(d))\
X == Sword)
X
X
X/* Match the pattern described by PBUFP against the virtual
X concatenation of STRING1 and STRING2, which are of SIZE1 and SIZE2,
X respectively. Start the match at index POS in the virtual
X concatenation of STRING1 and STRING2. In REGS, return the indices of
X the virtual concatenation of STRING1 and STRING2 that matched the
X entire PBUFP->buffer and its contained subexpressions. Do not
X consider matching one past the index MSTOP in the virtual
X concatenation of STRING1 and STRING2.
X
X If pbufp->fastmap is nonzero, then it had better be up to date.
X
X The reason that the data to match are specified as two components
X which are to be regarded as concatenated is so this function can be
X used directly on the contents of an Emacs buffer.
X
X -1 is returned if there is no match. -2 is returned if there is an
X error (such as match stack overflow). Otherwise the value is the
X length of the substring which was matched. */
X
Xint
Xre_match_2 (pbufp, string1_arg, size1, string2_arg, size2, pos, regs, mstop)
X struct re_pattern_buffer *pbufp;
X char *string1_arg, *string2_arg;
X int size1, size2;
X int pos;
X struct re_registers *regs;
X int mstop;
X{
X register unsigned char *p = (unsigned char *) pbufp->buffer;
X
X /* Pointer to beyond end of buffer. */
X register unsigned char *pend = p + pbufp->used;
X
X unsigned char *string1 = (unsigned char *) string1_arg;
X unsigned char *string2 = (unsigned char *) string2_arg;
X unsigned char *end1; /* Just past end of first string. */
X unsigned char *end2; /* Just past end of second string. */
X
X /* Pointers into string1 and string2, just past the last characters in
X each to consider matching. */
X unsigned char *end_match_1, *end_match_2;
X
X register unsigned char *d, *dend;
X register int mcnt; /* Multipurpose. */
X unsigned char *translate = (unsigned char *) pbufp->translate;
X unsigned is_a_jump_n = 0;
X
X /* Failure point stack. Each place that can handle a failure further
X down the line pushes a failure point on this stack. It consists of
X restart, regend, and reg_info for all registers corresponding to the
X subexpressions we're currently inside, plus the number of such
X registers, and, finally, two char *'s. The first char * is where to
X resume scanning the pattern; the second one is where to resume
X scanning the strings. If the latter is zero, the failure point is a
X ``dummy''; if a failure happens and the failure point is a dummy, it
X gets discarded and the next next one is tried. */
X
X unsigned char *initial_stack[MAX_NUM_FAILURE_ITEMS * NFAILURES];
X unsigned char **stackb = initial_stack;
X unsigned char **stackp = stackb;
X unsigned char **stacke = &stackb[MAX_NUM_FAILURE_ITEMS * NFAILURES];
X
X
X /* Information on the contents of registers. These are pointers into
X the input strings; they record just what was matched (on this
X attempt) by a subexpression part of the pattern, that is, the
X regnum-th regstart pointer points to where in the pattern we began
X matching and the regnum-th regend points to right after where we
X stopped matching the regnum-th subexpression. (The zeroth register
X keeps track of what the whole pattern matches.) */
X
X unsigned char *regstart[RE_NREGS];
X unsigned char *regend[RE_NREGS];
X
X /* The is_active field of reg_info helps us keep track of which (possibly
X nested) subexpressions we are currently in. The matched_something
X field of reg_info[reg_num] helps us tell whether or not we have
X matched any of the pattern so far this time through the reg_num-th
X subexpression. These two fields get reset each time through any
X loop their register is in. */
X
X struct register_info reg_info[RE_NREGS];
X
X
X /* The following record the register info as found in the above
X variables when we find a match better than any we've seen before.
X This happens as we backtrack through the failure points, which in
X turn happens only if we have not yet matched the entire string. */
X
X unsigned best_regs_set = 0;
X unsigned char *best_regstart[RE_NREGS];
X unsigned char *best_regend[RE_NREGS];
X
X
X /* Initialize subexpression text positions to -1 to mark ones that no
X \( or ( and \) or ) has been seen for. Also set all registers to
X inactive and mark them as not having matched anything or ever
X failed. */
X for (mcnt = 0; mcnt < RE_NREGS; mcnt++)
X {
X regstart[mcnt] = regend[mcnt] = (unsigned char *) -1;
X IS_ACTIVE (reg_info[mcnt]) = 0;
X MATCHED_SOMETHING (reg_info[mcnt]) = 0;
X }
X
X if (regs)
X for (mcnt = 0; mcnt < RE_NREGS; mcnt++)
X regs->start[mcnt] = regs->end[mcnt] = -1;
X
X /* Set up pointers to ends of strings.
X Don't allow the second string to be empty unless both are empty. */
X if (size2 == 0)
X {
X string2 = string1;
X size2 = size1;
X string1 = 0;
X size1 = 0;
X }
X end1 = string1 + size1;
X end2 = string2 + size2;
X
X /* Compute where to stop matching, within the two strings. */
X if (mstop <= size1)
X {
X end_match_1 = string1 + mstop;
X end_match_2 = string2;
X }
X else
X {
X end_match_1 = end1;
X end_match_2 = string2 + mstop - size1;
X }
X
X /* `p' scans through the pattern as `d' scans through the data. `dend'
X is the end of the input string that `d' points within. `d' is
X advanced into the following input string whenever necessary, but
X this happens before fetching; therefore, at the beginning of the
X loop, `d' can be pointing at the end of a string, but it cannot
X equal string2. */
X
X if (size1 != 0 && pos <= size1)
X d = string1 + pos, dend = end_match_1;
X else
X d = string2 + pos - size1, dend = end_match_2;
X
X
X /* This loops over pattern commands. It exits by returning from the
X function if match is complete, or it drops through if match fails
X at this starting point in the input data. */
X
X while (1)
X {
X is_a_jump_n = 0;
X /* End of pattern means we might have succeeded. */
X if (p == pend)
X {
X /* If not end of string, try backtracking. Otherwise done. */
X if (d != end_match_2)
X {
X if (stackp != stackb)
X {
X /* More failure points to try. */
X
X unsigned in_same_string =
X IS_IN_FIRST_STRING (best_regend[0])
X == MATCHING_IN_FIRST_STRING;
X
X /* If exceeds best match so far, save it. */
X if (! best_regs_set
X || (in_same_string && d > best_regend[0])
X || (! in_same_string && ! MATCHING_IN_FIRST_STRING))
X {
X best_regs_set = 1;
X best_regend[0] = d; /* Never use regstart[0]. */
X
X for (mcnt = 1; mcnt < RE_NREGS; mcnt++)
X {
X best_regstart[mcnt] = regstart[mcnt];
X best_regend[mcnt] = regend[mcnt];
X }
X }
X goto fail;
X }
X /* If no failure points, don't restore garbage. */
X else if (best_regs_set)
X {
X restore_best_regs:
X /* Restore best match. */
X d = best_regend[0];
X
X for (mcnt = 0; mcnt < RE_NREGS; mcnt++)
X {
X regstart[mcnt] = best_regstart[mcnt];
X regend[mcnt] = best_regend[mcnt];
X }
X }
X }
X
X /* If caller wants register contents data back, convert it
X to indices. */
X if (regs)
X {
X regs->start[0] = pos;
X if (MATCHING_IN_FIRST_STRING)
X regs->end[0] = d - string1;
X else
X regs->end[0] = d - string2 + size1;
X for (mcnt = 1; mcnt < RE_NREGS; mcnt++)
X {
X if (regend[mcnt] == (unsigned char *) -1)
X {
X regs->start[mcnt] = -1;
X regs->end[mcnt] = -1;
X continue;
X }
X if (IS_IN_FIRST_STRING (regstart[mcnt]))
X regs->start[mcnt] = regstart[mcnt] - string1;
X else
X regs->start[mcnt] = regstart[mcnt] - string2 + size1;
X
X if (IS_IN_FIRST_STRING (regend[mcnt]))
X regs->end[mcnt] = regend[mcnt] - string1;
X else
X regs->end[mcnt] = regend[mcnt] - string2 + size1;
X }
X }
X return d - pos - (MATCHING_IN_FIRST_STRING
X ? string1
X : string2 - size1);
X }
X
X /* Otherwise match next pattern command. */
X#ifdef SWITCH_ENUM_BUG
X switch ((int) ((enum regexpcode) *p++))
X#else
X switch ((enum regexpcode) *p++)
X#endif
X {
X
X /* \( [or `(', as appropriate] is represented by start_memory,
X \) by stop_memory. Both of those commands are followed by
X a register number in the next byte. The text matched
X within the \( and \) is recorded under that number. */
X case start_memory:
X regstart[*p] = d;
X IS_ACTIVE (reg_info[*p]) = 1;
X MATCHED_SOMETHING (reg_info[*p]) = 0;
X p++;
X break;
X
X case stop_memory:
X regend[*p] = d;
X IS_ACTIVE (reg_info[*p]) = 0;
X
X /* If just failed to match something this time around with a sub-
X expression that's in a loop, try to force exit from the loop. */
X if ((! MATCHED_SOMETHING (reg_info[*p])
X || (enum regexpcode) p[-3] == start_memory)
X && (p + 1) != pend)
X {
X register unsigned char *p2 = p + 1;
X mcnt = 0;
X switch (*p2++)
X {
X case jump_n:
X is_a_jump_n = 1;
X case finalize_jump:
X case maybe_finalize_jump:
X case jump:
X case dummy_failure_jump:
X EXTRACT_NUMBER_AND_INCR (mcnt, p2);
X if (is_a_jump_n)
X p2 += 2;
X break;
X }
X p2 += mcnt;
X
X /* If the next operation is a jump backwards in the pattern
X to an on_failure_jump, exit from the loop by forcing a
X failure after pushing on the stack the on_failure_jump's
X jump in the pattern, and d. */
X if (mcnt < 0 && (enum regexpcode) *p2++ == on_failure_jump)
X {
X EXTRACT_NUMBER_AND_INCR (mcnt, p2);
X PUSH_FAILURE_POINT (p2 + mcnt, d);
X goto fail;
X }
X }
X p++;
X break;
X
X /* \<digit> has been turned into a `duplicate' command which is
X followed by the numeric value of <digit> as the register number. */
X case duplicate:
X {
X int regno = *p++; /* Get which register to match against */
X register unsigned char *d2, *dend2;
X
X /* Where in input to try to start matching. */
X d2 = regstart[regno];
X
X /* Where to stop matching; if both the place to start and
X the place to stop matching are in the same string, then
X set to the place to stop, otherwise, for now have to use
X the end of the first string. */
X
X dend2 = ((IS_IN_FIRST_STRING (regstart[regno])
X == IS_IN_FIRST_STRING (regend[regno]))
X ? regend[regno] : end_match_1);
X while (1)
X {
X /* If necessary, advance to next segment in register
X contents. */
X while (d2 == dend2)
X {
X if (dend2 == end_match_2) break;
X if (dend2 == regend[regno]) break;
X d2 = string2, dend2 = regend[regno]; /* end of string1 => advance to string2. */
X }
X /* At end of register contents => success */
X if (d2 == dend2) break;
X
X /* If necessary, advance to next segment in data. */
X PREFETCH;
X
X /* How many characters left in this segment to match. */
X mcnt = dend - d;
X
X /* Want how many consecutive characters we can match in
X one shot, so, if necessary, adjust the count. */
X if (mcnt > dend2 - d2)
X mcnt = dend2 - d2;
X
X /* Compare that many; failure if mismatch, else move
X past them. */
X if (translate
X ? bcmp_translate (d, d2, mcnt, translate)
X : bcmp (d, d2, mcnt))
X goto fail;
X d += mcnt, d2 += mcnt;
X }
X }
X break;
X
X case anychar:
X PREFETCH; /* Fetch a data character. */
X /* Match anything but a newline, maybe even a null. */
X if ((translate ? translate[*d] : *d) == '\n'
X || ((obscure_syntax & RE_DOT_NOT_NULL)
X && (translate ? translate[*d] : *d) == '\000'))
X goto fail;
X SET_REGS_MATCHED;
X d++;
X break;
X
X case charset:
X case charset_not:
X {
X int not = 0; /* Nonzero for charset_not. */
X register int c;
X if (*(p - 1) == (unsigned char) charset_not)
X not = 1;
X
X PREFETCH; /* Fetch a data character. */
X
X if (translate)
X c = translate[*d];
X else
X c = *d;
X
X if (c < *p * BYTEWIDTH
X && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
X not = !not;
X
X p += 1 + *p;
X
X if (!not) goto fail;
X SET_REGS_MATCHED;
X d++;
X break;
X }
X
X case begline:
X if ((size1 != 0 && d == string1)
X || (size1 == 0 && size2 != 0 && d == string2)
X || (d && d[-1] == '\n')
X || (size1 == 0 && size2 == 0))
X break;
X else
X goto fail;
X
X case endline:
X if (d == end2
X || (d == end1 ? (size2 == 0 || *string2 == '\n') : *d == '\n'))
X break;
X goto fail;
X
X /* `or' constructs are handled by starting each alternative with
X an on_failure_jump that points to the start of the next
X alternative. Each alternative except the last ends with a
X jump to the joining point. (Actually, each jump except for
X the last one really jumps to the following jump, because
X tensioning the jumps is a hassle.) */
X
X /* The start of a stupid repeat has an on_failure_jump that points
X past the end of the repeat text. This makes a failure point so
X that on failure to match a repetition, matching restarts past
X as many repetitions have been found with no way to fail and
X look for another one. */
X
X /* A smart repeat is similar but loops back to the on_failure_jump
X so that each repetition makes another failure point. */
X
X case on_failure_jump:
X on_failure:
X EXTRACT_NUMBER_AND_INCR (mcnt, p);
X PUSH_FAILURE_POINT (p + mcnt, d);
X break;
X
X /* The end of a smart repeat has a maybe_finalize_jump back.
X Change it either to a finalize_jump or an ordinary jump. */
X case maybe_finalize_jump:
X EXTRACT_NUMBER_AND_INCR (mcnt, p);
X {
X register unsigned char *p2 = p;
X /* Compare what follows with the beginning of the repeat.
X If we can establish that there is nothing that they would
X both match, we can change to finalize_jump. */
X while (p2 + 1 != pend
X && (*p2 == (unsigned char) stop_memory
X || *p2 == (unsigned char) start_memory))
X p2 += 2; /* Skip over reg number. */
X if (p2 == pend)
X p[-3] = (unsigned char) finalize_jump;
X else if (*p2 == (unsigned char) exactn
X || *p2 == (unsigned char) endline)
X {
X register int c = *p2 == (unsigned char) endline ? '\n' : p2[2];
X register unsigned char *p1 = p + mcnt;
X /* p1[0] ... p1[2] are an on_failure_jump.
X Examine what follows that. */
X if (p1[3] == (unsigned char) exactn && p1[5] != c)
X p[-3] = (unsigned char) finalize_jump;
X else if (p1[3] == (unsigned char) charset
X || p1[3] == (unsigned char) charset_not)
X {
X int not = p1[3] == (unsigned char) charset_not;
X if (c < p1[4] * BYTEWIDTH
X && p1[5 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
X not = !not;
X /* `not' is 1 if c would match. */
X /* That means it is not safe to finalize. */
X if (!not)
X p[-3] = (unsigned char) finalize_jump;
X }
X }
X }
X p -= 2; /* Point at relative address again. */
X if (p[-1] != (unsigned char) finalize_jump)
X {
X p[-1] = (unsigned char) jump;
X goto nofinalize;
X }
X /* Note fall through. */
X
X /* The end of a stupid repeat has a finalize_jump back to the
X start, where another failure point will be made which will
X point to after all the repetitions found so far. */
X
X /* Take off failure points put on by matching on_failure_jump
X because didn't fail. Also remove the register information
X put on by the on_failure_jump. */
X case finalize_jump:
X POP_FAILURE_POINT ();
X /* Note fall through. */
X
X /* Jump without taking off any failure points. */
X case jump:
X nofinalize:
X EXTRACT_NUMBER_AND_INCR (mcnt, p);
X p += mcnt;
X break;
X
X case dummy_failure_jump:
X /* Normally, the on_failure_jump pushes a failure point, which
X then gets popped at finalize_jump. We will end up at
X finalize_jump, also, and with a pattern of, say, `a+', we
X are skipping over the on_failure_jump, so we have to push
X something meaningless for finalize_jump to pop. */
X PUSH_FAILURE_POINT (0, 0);
X goto nofinalize;
X
X
X /* Have to succeed matching what follows at least n times. Then
X just handle like an on_failure_jump. */
X case succeed_n:
X EXTRACT_NUMBER (mcnt, p + 2);
X /* Originally, this is how many times we HAVE to succeed. */
X if (mcnt)
X {
X mcnt--;
X p += 2;
X STORE_NUMBER_AND_INCR (p, mcnt);
X }
X else if (mcnt == 0)
X {
X p[2] = unused;
X p[3] = unused;
X goto on_failure;
X }
X else
X {
X fprintf (stderr, "regex: the succeed_n's n is not set.\n");
X exit (1);
X }
X break;
X
X case jump_n:
X EXTRACT_NUMBER (mcnt, p + 2);
X /* Originally, this is how many times we CAN jump. */
X if (mcnt)
X {
X mcnt--;
X STORE_NUMBER(p + 2, mcnt);
X goto nofinalize; /* Do the jump without taking off
X any failure points. */
X }
X /* If don't have to jump any more, skip over the rest of command. */
X else
X p += 4;
X break;
X
X case set_number_at:
X {
X register unsigned char *p1;
X
X EXTRACT_NUMBER_AND_INCR (mcnt, p);
X p1 = p + mcnt;
X EXTRACT_NUMBER_AND_INCR (mcnt, p);
X STORE_NUMBER (p1, mcnt);
X break;
X }
X
X /* Ignore these. Used to ignore the n of succeed_n's which
X currently have n == 0. */
X case unused:
X break;
X
X case wordbound:
X if (AT_WORD_BOUNDARY)
X break;
X goto fail;
X
X case notwordbound:
X if (AT_WORD_BOUNDARY)
X goto fail;
X break;
X
X case wordbeg:
X if (IS_A_LETTER (d) && (!IS_A_LETTER (d - 1) || AT_STRINGS_BEG))
X break;
X goto fail;
X
X case wordend:
X /* Have to check if AT_STRINGS_BEG before looking at d - 1. */
X if (!AT_STRINGS_BEG && IS_A_LETTER (d - 1)
X && (!IS_A_LETTER (d) || AT_STRINGS_END))
X break;
X goto fail;
X
X#ifdef emacs
X case before_dot:
X if (PTR_CHAR_POS (d) >= point)
X goto fail;
X break;
X
X case at_dot:
X if (PTR_CHAR_POS (d) != point)
X goto fail;
X break;
X
X case after_dot:
X if (PTR_CHAR_POS (d) <= point)
X goto fail;
X break;
X
X case wordchar:
X mcnt = (int) Sword;
X goto matchsyntax;
X
X case syntaxspec:
X mcnt = *p++;
X matchsyntax:
X PREFETCH;
X if (SYNTAX (*d++) != (enum syntaxcode) mcnt) goto fail;
X SET_REGS_MATCHED;
X break;
X
X case notwordchar:
X mcnt = (int) Sword;
X goto matchnotsyntax;
X
X case notsyntaxspec:
X mcnt = *p++;
X matchnotsyntax:
X PREFETCH;
X if (SYNTAX (*d++) == (enum syntaxcode) mcnt) goto fail;
X SET_REGS_MATCHED;
X break;
X
X#else /* not emacs */
X
X case wordchar:
X PREFETCH;
X if (!IS_A_LETTER (d))
X goto fail;
X SET_REGS_MATCHED;
X break;
X
X case notwordchar:
X PREFETCH;
X if (IS_A_LETTER (d))
X goto fail;
X SET_REGS_MATCHED;
X break;
X
X#endif /* not emacs */
X
X case begbuf:
X if (AT_STRINGS_BEG)
X break;
X goto fail;
X
X case endbuf:
X if (AT_STRINGS_END)
X break;
X goto fail;
X
X case exactn:
X /* Match the next few pattern characters exactly.
X mcnt is how many characters to match. */
X mcnt = *p++;
X /* This is written out as an if-else so we don't waste time
X testing `translate' inside the loop. */
X if (translate)
X {
X do
X {
X PREFETCH;
X if (translate[*d++] != *p++) goto fail;
X }
X while (--mcnt);
X }
X else
X {
X do
X {
X PREFETCH;
X if (*d++ != *p++) goto fail;
X }
X while (--mcnt);
X }
X SET_REGS_MATCHED;
X break;
X }
X continue; /* Successfully executed one pattern command; keep going. */
X
X /* Jump here if any matching operation fails. */
X fail:
X if (stackp != stackb)
X /* A restart point is known. Restart there and pop it. */
X {
X short last_used_reg, this_reg;
X
X /* If this failure point is from a dummy_failure_point, just
X skip it. */
X if (!stackp[-2])
X {
X POP_FAILURE_POINT ();
X goto fail;
X }
X
X d = *--stackp;
X p = *--stackp;
X if (d >= string1 && d <= end1)
X dend = end_match_1;
X /* Restore register info. */
X last_used_reg = (short) *--stackp;
X
X /* Make the ones that weren't saved -1 or 0 again. */
X for (this_reg = RE_NREGS - 1; this_reg > last_used_reg; this_reg--)
X {
X regend[this_reg] = (unsigned char *) -1;
X regstart[this_reg] = (unsigned char *) -1;
X IS_ACTIVE (reg_info[this_reg]) = 0;
X MATCHED_SOMETHING (reg_info[this_reg]) = 0;
X }
X
X /* And restore the rest from the stack. */
X for ( ; this_reg > 0; this_reg--)
X {
X reg_info[this_reg] = *(struct register_info *) *--stackp;
X regend[this_reg] = *--stackp;
X regstart[this_reg] = *--stackp;
X }
X }
X else
X break; /* Matching at this starting point really fails. */
X }
X
X if (best_regs_set)
X goto restore_best_regs;
X return -1; /* Failure to match. */
X}
X
X
Xstatic int
Xbcmp_translate (s1, s2, len, translate)
X unsigned char *s1, *s2;
X register int len;
X unsigned char *translate;
X{
X register unsigned char *p1 = s1, *p2 = s2;
X while (len)
X {
X if (translate [*p1++] != translate [*p2++]) return 1;
X len--;
X }
X return 0;
X}
X
X
X
X/* Entry points compatible with 4.2 BSD regex library. */
X
X#ifndef emacs
X
Xstatic struct re_pattern_buffer re_comp_buf;
X
Xchar *
Xre_comp (s)
X char *s;
X{
X if (!s)
X {
X if (!re_comp_buf.buffer)
X return "No previous regular expression";
X return 0;
X }
X
X if (!re_comp_buf.buffer)
X {
X if (!(re_comp_buf.buffer = (char *) malloc (200)))
X return "Memory exhausted";
X re_comp_buf.allocated = 200;
X if (!(re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH)))
X return "Memory exhausted";
X }
X return re_compile_pattern (s, strlen (s), &re_comp_buf);
X}
X
Xint
Xre_exec (s)
X char *s;
X{
X int len = strlen (s);
X return 0 <= re_search (&re_comp_buf, s, len, 0, len,
X (struct re_registers *) 0);
X}
X#endif /* not emacs */
X
X
X
X#ifdef test
X
X#include <stdio.h>
X
X/* Indexed by a character, gives the upper case equivalent of the
X character. */
X
Xchar upcase[0400] =
X { 000, 001, 002, 003, 004, 005, 006, 007,
X 010, 011, 012, 013, 014, 015, 016, 017,
X 020, 021, 022, 023, 024, 025, 026, 027,
X 030, 031, 032, 033, 034, 035, 036, 037,
X 040, 041, 042, 043, 044, 045, 046, 047,
X 050, 051, 052, 053, 054, 055, 056, 057,
X 060, 061, 062, 063, 064, 065, 066, 067,
X 070, 071, 072, 073, 074, 075, 076, 077,
X 0100, 0101, 0102, 0103, 0104, 0105, 0106, 0107,
X 0110, 0111, 0112, 0113, 0114, 0115, 0116, 0117,
X 0120, 0121, 0122, 0123, 0124, 0125, 0126, 0127,
X 0130, 0131, 0132, 0133, 0134, 0135, 0136, 0137,
X 0140, 0101, 0102, 0103, 0104, 0105, 0106, 0107,
X 0110, 0111, 0112, 0113, 0114, 0115, 0116, 0117,
X 0120, 0121, 0122, 0123, 0124, 0125, 0126, 0127,
X 0130, 0131, 0132, 0173, 0174, 0175, 0176, 0177,
X 0200, 0201, 0202, 0203, 0204, 0205, 0206, 0207,
X 0210, 0211, 0212, 0213, 0214, 0215, 0216, 0217,
X 0220, 0221, 0222, 0223, 0224, 0225, 0226, 0227,
X 0230, 0231, 0232, 0233, 0234, 0235, 0236, 0237,
X 0240, 0241, 0242, 0243, 0244, 0245, 0246, 0247,
X 0250, 0251, 0252, 0253, 0254, 0255, 0256, 0257,
X 0260, 0261, 0262, 0263, 0264, 0265, 0266, 0267,
X 0270, 0271, 0272, 0273, 0274, 0275, 0276, 0277,
X 0300, 0301, 0302, 0303, 0304, 0305, 0306, 0307,
X 0310, 0311, 0312, 0313, 0314, 0315, 0316, 0317,
X 0320, 0321, 0322, 0323, 0324, 0325, 0326, 0327,
X 0330, 0331, 0332, 0333, 0334, 0335, 0336, 0337,
X 0340, 0341, 0342, 0343, 0344, 0345, 0346, 0347,
X 0350, 0351, 0352, 0353, 0354, 0355, 0356, 0357,
X 0360, 0361, 0362, 0363, 0364, 0365, 0366, 0367,
X 0370, 0371, 0372, 0373, 0374, 0375, 0376, 0377
X };
X
X#ifdef canned
X
X#include "tests.h"
X
Xtypedef enum { extended_test, basic_test } test_type;
X
X/* Use this to run the tests we've thought of. */
X
Xvoid
Xmain ()
X{
X test_type t = extended_test;
X
X if (t == basic_test)
X {
X printf ("Running basic tests:\n\n");
X test_posix_basic ();
X }
X else if (t == extended_test)
X {
X printf ("Running extended tests:\n\n");
X test_posix_extended ();
X }
X}
X
X#else /* not canned */
X
X/* Use this to run interactive tests. */
X
Xvoid
Xmain (argc, argv)
X int argc;
X char **argv;
X{
X char pat[80];
X struct re_pattern_buffer buf;
X int i;
X char c;
X char fastmap[(1 << BYTEWIDTH)];
X
X /* Allow a command argument to specify the style of syntax. */
X if (argc > 1)
X obscure_syntax = atoi (argv[1]);
X
X buf.allocated = 40;
X buf.buffer = (char *) malloc (buf.allocated);
X buf.fastmap = fastmap;
X buf.translate = upcase;
X
X while (1)
X {
X gets (pat);
X
X if (*pat)
X {
X re_compile_pattern (pat, strlen(pat), &buf);
X
X for (i = 0; i < buf.used; i++)
X printchar (buf.buffer[i]);
X
X putchar ('\n');
X
X printf ("%d allocated, %d used.\n", buf.allocated, buf.used);
X
X re_compile_fastmap (&buf);
X printf ("Allowed by fastmap: ");
X for (i = 0; i < (1 << BYTEWIDTH); i++)
X if (fastmap[i]) printchar (i);
X putchar ('\n');
X }
X
X gets (pat); /* Now read the string to match against */
X
X i = re_match (&buf, pat, strlen (pat), 0, 0);
X printf ("Match value %d.\n", i);
X }
X}
X
X#endif
X
X
X#ifdef NOTDEF
Xprint_buf (bufp)
X struct re_pattern_buffer *bufp;
X{
X int i;
X
X printf ("buf is :\n----------------\n");
X for (i = 0; i < bufp->used; i++)
X printchar (bufp->buffer[i]);
X
X printf ("\n%d allocated, %d used.\n", bufp->allocated, bufp->used);
X
X printf ("Allowed by fastmap: ");
X for (i = 0; i < (1 << BYTEWIDTH); i++)
X if (bufp->fastmap[i])
X printchar (i);
X printf ("\nAllowed by translate: ");
X if (bufp->translate)
X for (i = 0; i < (1 << BYTEWIDTH); i++)
X if (bufp->translate[i])
X printchar (i);
X printf ("\nfastmap is%s accurate\n", bufp->fastmap_accurate ? "" : "n't");
X printf ("can %s be null\n----------", bufp->can_be_null ? "" : "not");
X}
X#endif /* NOTDEF */
X
Xprintchar (c)
X char c;
X{
X if (c < 040 || c >= 0177)
X {
X putchar ('\\');
X putchar (((c >> 6) & 3) + '0');
X putchar (((c >> 3) & 7) + '0');
X putchar ((c & 7) + '0');
X }
X else
X putchar (c);
X}
X
Xerror (string)
X char *string;
X{
X puts (string);
X exit (1);
X}
X#endif /* test */
END_OF_FILE
if test 37881 -ne `wc -c <'regex.c2'`; then
echo shar: \"'regex.c2'\" unpacked with wrong size!
fi
# end of 'regex.c2'
fi
if test -r regex.c1 -a -r regex.c2
then
echo shar: concatenating \"regex.c1\" and \"regex.c2\" into \"regex.c\"
cat regex.c1 regex.c2 >regex.c || echo shar: \"regex.c\" creation failed!
fi
echo shar: End of archive 6 \(of 8\).
cp /dev/null ark6isdone
MISSING=""
for I in 1 2 3 4 5 6 7 8 ; do
if test ! -f ark${I}isdone ; then
MISSING="${MISSING} ${I}"
fi
done
if test "${MISSING}" = "" ; then
echo You have unpacked all 8 archives.
rm -f ark[1-9]isdone
else
echo You still need to unpack the following archives:
echo " " ${MISSING}
fi
## End of shell archive.
exit 0
exit 0 # Just in case...
--
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