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Update bundled PCRE2-library to version 10.23

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Some manual changes done to the library were lost with this update.
They will be added in the next commit.
This commit is contained in:
Esa Korhonen
2017-05-29 15:31:42 +03:00
parent 7231563937
commit 36af74cb25
218 changed files with 49218 additions and 26130 deletions
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326
pcre2/src/pcre2_study.c
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@ -7,7 +7,7 @@ and semantics are as close as possible to those of the Perl 5 language.
Written by Philip Hazel
Original API code Copyright (c) 1997-2012 University of Cambridge
New API code Copyright (c) 2014 University of Cambridge
New API code Copyright (c) 2016 University of Cambridge
-----------------------------------------------------------------------------
Redistribution and use in source and binary forms, with or without
@ -50,6 +50,10 @@ collecting data (e.g. minimum matching length). */
#include "pcre2_internal.h"
/* The maximum remembered capturing brackets minimum. */
#define MAX_CACHE_BACKREF 128
/* Set a bit in the starting code unit bit map. */
#define SET_BIT(c) re->start_bitmap[(c)/8] |= (1 << ((c)&7))
@ -59,15 +63,23 @@ collecting data (e.g. minimum matching length). */
enum { SSB_FAIL, SSB_DONE, SSB_CONTINUE, SSB_UNKNOWN };
/*************************************************
* Find the minimum subject length for a group *
*************************************************/
/* Scan a parenthesized group and compute the minimum length of subject that
is needed to match it. This is a lower bound; it does not mean there is a
string of that length that matches. In UTF8 mode, the result is in characters
rather than bytes.
string of that length that matches. In UTF mode, the result is in characters
rather than code units. The field in a compiled pattern for storing the minimum
length is 16-bits long (on the grounds that anything longer than that is
pathological), so we give up when we reach that amount. This also means that
integer overflow for really crazy patterns cannot happen.
Backreference minimum lengths are cached to speed up multiple references. This
function is called only when the highest back reference in the pattern is less
than or equal to MAX_CACHE_BACKREF, which is one less than the size of the
caching vector. The zeroth element contains the number of the highest set
value.
Arguments:
re compiled pattern block
@ -75,35 +87,58 @@ Arguments:
startcode pointer to start of the whole pattern's code
utf UTF flag
recurses chain of recurse_check to catch mutual recursion
countptr pointer to call count (to catch over complexity)
backref_cache vector for caching back references.
Returns: the minimum length
-1 \C in UTF-8 mode
or (*ACCEPT)
or pattern too complicated
or back reference to duplicate name/number
-2 internal error (missing capturing bracket)
-3 internal error (opcode not listed)
*/
static int
find_minlength(const pcre2_real_code *re, PCRE2_SPTR code,
PCRE2_SPTR startcode, BOOL utf, recurse_check *recurses)
PCRE2_SPTR startcode, BOOL utf, recurse_check *recurses, int *countptr,
int *backref_cache)
{
int length = -1;
int prev_cap_recno = -1;
int prev_cap_d = 0;
int prev_recurse_recno = -1;
int prev_recurse_d = 0;
uint32_t once_fudge = 0;
BOOL had_recurse = FALSE;
BOOL dupcapused = (re->flags & PCRE2_DUPCAPUSED) != 0;
recurse_check this_recurse;
register int branchlength = 0;
register PCRE2_UCHAR *cc = (PCRE2_UCHAR *)code + 1 + LINK_SIZE;
int branchlength = 0;
PCRE2_UCHAR *cc = (PCRE2_UCHAR *)code + 1 + LINK_SIZE;
if (*code == OP_CBRA || *code == OP_SCBRA ||
*code == OP_CBRAPOS || *code == OP_SCBRAPOS) cc += IMM2_SIZE;
/* If this is a "could be empty" group, its minimum length is 0. */
/* Scan along the opcodes for this branch. If we get to the end of the
branch, check the length against that of the other branches. */
if (*code >= OP_SBRA && *code <= OP_SCOND) return 0;
/* Skip over capturing bracket number */
if (*code == OP_CBRA || *code == OP_CBRAPOS) cc += IMM2_SIZE;
/* A large and/or complex regex can take too long to process. */
if ((*countptr)++ > 1000) return -1;
/* Scan along the opcodes for this branch. If we get to the end of the branch,
check the length against that of the other branches. If the accumulated length
passes 16-bits, stop. */
for (;;)
{
int d, min;
int d, min, recno;
PCRE2_UCHAR *cs, *ce;
register PCRE2_UCHAR op = *cc;
PCRE2_UCHAR op = *cc;
if (branchlength >= UINT16_MAX) return UINT16_MAX;
switch (op)
{
@ -112,7 +147,8 @@ for (;;)
/* If there is only one branch in a condition, the implied branch has zero
length, so we don't add anything. This covers the DEFINE "condition"
automatically. */
automatically. If there are two branches we can treat it the same as any
other non-capturing subpattern. */
cs = cc + GET(cc, 1);
if (*cs != OP_ALT)
@ -120,23 +156,54 @@ for (;;)
cc = cs + 1 + LINK_SIZE;
break;
}
goto PROCESS_NON_CAPTURE;
/* Otherwise we can fall through and treat it the same as any other
subpattern. */
/* There's a special case of OP_ONCE, when it is wrapped round an
OP_RECURSE. We'd like to process the latter at this level so that
remembering the value works for repeated cases. So we do nothing, but
set a fudge value to skip over the OP_KET after the recurse. */
case OP_ONCE:
if (cc[1+LINK_SIZE] == OP_RECURSE && cc[2*(1+LINK_SIZE)] == OP_KET)
{
once_fudge = 1 + LINK_SIZE;
cc += 1 + LINK_SIZE;
break;
}
/* Fall through */
case OP_ONCE_NC:
case OP_BRA:
case OP_SBRA:
case OP_BRAPOS:
case OP_SBRAPOS:
PROCESS_NON_CAPTURE:
d = find_minlength(re, cc, startcode, utf, recurses, countptr,
backref_cache);
if (d < 0) return d;
branchlength += d;
do cc += GET(cc, 1); while (*cc == OP_ALT);
cc += 1 + LINK_SIZE;
break;
/* To save time for repeated capturing subpatterns, we remember the
length of the previous one. Unfortunately we can't do the same for
the unnumbered ones above. Nor can we do this if (?| is present in the
pattern because captures with the same number are not then identical. */
case OP_CBRA:
case OP_SCBRA:
case OP_BRA:
case OP_SBRA:
case OP_CBRAPOS:
case OP_SCBRAPOS:
case OP_BRAPOS:
case OP_SBRAPOS:
case OP_ONCE:
case OP_ONCE_NC:
d = find_minlength(re, cc, startcode, utf, recurses);
if (d < 0) return d;
branchlength += d;
recno = (int)GET2(cc, 1+LINK_SIZE);
if (dupcapused || recno != prev_cap_recno)
{
prev_cap_recno = recno;
prev_cap_d = find_minlength(re, cc, startcode, utf, recurses, countptr,
backref_cache);
if (prev_cap_d < 0) return prev_cap_d;
}
branchlength += prev_cap_d;
do cc += GET(cc, 1); while (*cc == OP_ALT);
cc += 1 + LINK_SIZE;
break;
@ -388,8 +455,12 @@ for (;;)
matches an empty string (by default it causes a matching failure), so in
that case we must set the minimum length to zero. */
case OP_DNREF: /* Duplicate named pattern back reference */
/* Duplicate named pattern back reference. We cannot reliably find a length
for this if duplicate numbers are present in the pattern. */
case OP_DNREF:
case OP_DNREFI:
if (dupcapused) return -1;
if ((re->overall_options & PCRE2_MATCH_UNSET_BACKREF) == 0)
{
int count = GET2(cc, 1+IMM2_SIZE);
@ -399,18 +470,80 @@ for (;;)
d = INT_MAX;
/* Scan all groups with the same name */
/* Scan all groups with the same name; find the shortest. */
while (count-- > 0)
{
ce = cs = (PCRE2_UCHAR *)PRIV(find_bracket)(startcode, utf, GET2(slot, 0));
int dd, i;
recno = GET2(slot, 0);
if (recno <= backref_cache[0] && backref_cache[recno] >= 0)
dd = backref_cache[recno];
else
{
ce = cs = (PCRE2_UCHAR *)PRIV(find_bracket)(startcode, utf, recno);
if (cs == NULL) return -2;
do ce += GET(ce, 1); while (*ce == OP_ALT);
if (cc > cs && cc < ce) /* Simple recursion */
{
dd = 0;
had_recurse = TRUE;
}
else
{
recurse_check *r = recurses;
for (r = recurses; r != NULL; r = r->prev)
if (r->group == cs) break;
if (r != NULL) /* Mutual recursion */
{
dd = 0;
had_recurse = TRUE;
}
else
{
this_recurse.prev = recurses;
this_recurse.group = cs;
dd = find_minlength(re, cs, startcode, utf, &this_recurse,
countptr, backref_cache);
if (dd < 0) return dd;
}
}
backref_cache[recno] = dd;
for (i = backref_cache[0] + 1; i < recno; i++) backref_cache[i] = -1;
backref_cache[0] = recno;
}
if (dd < d) d = dd;
if (d <= 0) break; /* No point looking at any more */
slot += re->name_entry_size;
}
}
else d = 0;
cc += 1 + 2*IMM2_SIZE;
goto REPEAT_BACK_REFERENCE;
/* Single back reference. We cannot find a length for this if duplicate
numbers are present in the pattern. */
case OP_REF:
case OP_REFI:
if (dupcapused) return -1;
recno = GET2(cc, 1);
if (recno <= backref_cache[0] && backref_cache[recno] >= 0)
d = backref_cache[recno];
else
{
int i;
if ((re->overall_options & PCRE2_MATCH_UNSET_BACKREF) == 0)
{
ce = cs = (PCRE2_UCHAR *)PRIV(find_bracket)(startcode, utf, recno);
if (cs == NULL) return -2;
do ce += GET(ce, 1); while (*ce == OP_ALT);
if (cc > cs && cc < ce) /* Simple recursion */
{
d = 0;
had_recurse = TRUE;
break;
}
else
{
@ -420,54 +553,24 @@ for (;;)
{
d = 0;
had_recurse = TRUE;
break;
}
else
{
int dd;
this_recurse.prev = recurses;
this_recurse.group = cs;
dd = find_minlength(re, cs, startcode, utf, &this_recurse);
if (dd < d) d = dd;
d = find_minlength(re, cs, startcode, utf, &this_recurse, countptr,
backref_cache);
if (d < 0) return d;
}
}
slot += re->name_entry_size;
}
}
else d = 0;
cc += 1 + 2*IMM2_SIZE;
goto REPEAT_BACK_REFERENCE;
else d = 0;
case OP_REF: /* Single back reference */
case OP_REFI:
if ((re->overall_options & PCRE2_MATCH_UNSET_BACKREF) == 0)
{
ce = cs = (PCRE2_UCHAR *)PRIV(find_bracket)(startcode, utf, GET2(cc, 1));
if (cs == NULL) return -2;
do ce += GET(ce, 1); while (*ce == OP_ALT);
if (cc > cs && cc < ce) /* Simple recursion */
{
d = 0;
had_recurse = TRUE;
}
else
{
recurse_check *r = recurses;
for (r = recurses; r != NULL; r = r->prev) if (r->group == cs) break;
if (r != NULL) /* Mutual recursion */
{
d = 0;
had_recurse = TRUE;
}
else
{
this_recurse.prev = recurses;
this_recurse.group = cs;
d = find_minlength(re, cs, startcode, utf, &this_recurse);
}
}
backref_cache[recno] = d;
for (i = backref_cache[0] + 1; i < recno; i++) backref_cache[i] = -1;
backref_cache[0] = recno;
}
else d = 0;
cc += 1 + IMM2_SIZE;
/* Handle repeated back references */
@ -504,28 +607,51 @@ for (;;)
break;
}
branchlength += min * d;
/* Take care not to overflow: (1) min and d are ints, so check that their
product is not greater than INT_MAX. (2) branchlength is limited to
UINT16_MAX (checked at the top of the loop). */
if ((d > 0 && (INT_MAX/d) < min) || UINT16_MAX - branchlength < min*d)
branchlength = UINT16_MAX;
else branchlength += min * d;
break;
/* Recursion always refers to the first occurrence of a subpattern with a
given number. Therefore, we can always make use of caching, even when the
pattern contains multiple subpatterns with the same number. */
case OP_RECURSE:
cs = ce = (PCRE2_UCHAR *)startcode + GET(cc, 1);
do ce += GET(ce, 1); while (*ce == OP_ALT);
if (cc > cs && cc < ce) /* Simple recursion */
had_recurse = TRUE;
recno = GET2(cs, 1+LINK_SIZE);
if (recno == prev_recurse_recno)
{
branchlength += prev_recurse_d;
}
else
{
recurse_check *r = recurses;
for (r = recurses; r != NULL; r = r->prev) if (r->group == cs) break;
if (r != NULL) /* Mutual recursion */
do ce += GET(ce, 1); while (*ce == OP_ALT);
if (cc > cs && cc < ce) /* Simple recursion */
had_recurse = TRUE;
else
{
this_recurse.prev = recurses;
this_recurse.group = cs;
branchlength += find_minlength(re, cs, startcode, utf, &this_recurse);
recurse_check *r = recurses;
for (r = recurses; r != NULL; r = r->prev) if (r->group == cs) break;
if (r != NULL) /* Mutual recursion */
had_recurse = TRUE;
else
{
this_recurse.prev = recurses;
this_recurse.group = cs;
prev_recurse_d = find_minlength(re, cs, startcode, utf, &this_recurse,
countptr, backref_cache);
if (prev_recurse_d < 0) return prev_recurse_d;
prev_recurse_recno = recno;
branchlength += prev_recurse_d;
}
}
}
cc += 1 + LINK_SIZE;
cc += 1 + LINK_SIZE + once_fudge;
once_fudge = 0;
break;
/* Anything else does not or need not match a character. We can get the
@ -708,7 +834,7 @@ Returns: nothing
static void
set_type_bits(pcre2_real_code *re, int cbit_type, unsigned int table_limit)
{
register uint32_t c;
uint32_t c;
for (c = 0; c < table_limit; c++)
re->start_bitmap[c] |= re->tables[c+cbits_offset+cbit_type];
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
@ -749,7 +875,7 @@ Returns: nothing
static void
set_nottype_bits(pcre2_real_code *re, int cbit_type, unsigned int table_limit)
{
register uint32_t c;
uint32_t c;
for (c = 0; c < table_limit; c++)
re->start_bitmap[c] |= ~(re->tables[c+cbits_offset+cbit_type]);
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
@ -789,7 +915,7 @@ Returns: SSB_FAIL => Failed to find any starting code units
static int
set_start_bits(pcre2_real_code *re, PCRE2_SPTR code, BOOL utf)
{
register uint32_t c;
uint32_t c;
int yield = SSB_DONE;
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
@ -1368,7 +1494,7 @@ do
for (c = 0; c < 16; c++) re->start_bitmap[c] |= classmap[c];
for (c = 128; c < 256; c++)
{
if ((classmap[c/8] && (1 << (c&7))) != 0)
if ((classmap[c/8] & (1 << (c&7))) != 0)
{
int d = (c >> 6) | 0xc0; /* Set bit for this starter */
re->start_bitmap[d/8] |= (1 << (d&7)); /* and then skip on to the */
@ -1441,6 +1567,7 @@ int
PRIV(study)(pcre2_real_code *re)
{
int min;
int count = 0;
PCRE2_UCHAR *code;
BOOL utf = (re->overall_options & PCRE2_UTF) != 0;
@ -1461,22 +1588,35 @@ if ((re->overall_options & PCRE2_ANCHORED) == 0 &&
if (rc == SSB_DONE) re->flags |= PCRE2_FIRSTMAPSET;
}
/* Find the minimum length of subject string. */
/* Find the minimum length of subject string. If the pattern can match an empty
string, the minimum length is already known. If there are more back references
than the size of the vector we are going to cache them in, do nothing. A
pattern that complicated will probably take a long time to analyze and may in
any case turn out to be too complicated. Note that back reference minima are
held as 16-bit numbers. */
switch(min = find_minlength(re, code, code, utf, NULL))
if ((re->flags & PCRE2_MATCH_EMPTY) == 0 &&
re->top_backref <= MAX_CACHE_BACKREF)
{
case -1: /* \C in UTF mode or (*ACCEPT) */
break; /* Leave minlength unchanged (will be zero) */
int backref_cache[MAX_CACHE_BACKREF+1];
backref_cache[0] = 0; /* Highest one that is set */
min = find_minlength(re, code, code, utf, NULL, &count, backref_cache);
switch(min)
{
case -1: /* \C in UTF mode or (*ACCEPT) or over-complex regex */
break; /* Leave minlength unchanged (will be zero) */
case -2:
return 2; /* missing capturing bracket */
case -2:
return 2; /* missing capturing bracket */
case -3:
return 3; /* unrecognized opcode */
case -3:
return 3; /* unrecognized opcode */
default:
re->minlength = min;
break;
default:
if (min > UINT16_MAX) min = UINT16_MAX;
re->minlength = min;
break;
}
}
return 0;