pcre2/src/pcre2_substring.c

548 lines
18 KiB
C

/*************************************************
* Perl-Compatible Regular Expressions *
*************************************************/
/* PCRE is a library of functions to support regular expressions whose syntax
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) 2016-2018 University of Cambridge
-----------------------------------------------------------------------------
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of the University of Cambridge nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
-----------------------------------------------------------------------------
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "pcre2_internal.h"
/*************************************************
* Copy named captured string to given buffer *
*************************************************/
/* This function copies a single captured substring into a given buffer,
identifying it by name. If the regex permits duplicate names, the first
substring that is set is chosen.
Arguments:
match_data points to the match data
stringname the name of the required substring
buffer where to put the substring
sizeptr the size of the buffer, updated to the size of the substring
Returns: if successful: zero
if not successful, a negative error code:
(1) an error from nametable_scan()
(2) an error from copy_bynumber()
(3) PCRE2_ERROR_UNAVAILABLE: no group is in ovector
(4) PCRE2_ERROR_UNSET: all named groups in ovector are unset
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_copy_byname(pcre2_match_data *match_data, PCRE2_SPTR stringname,
PCRE2_UCHAR *buffer, PCRE2_SIZE *sizeptr)
{
PCRE2_SPTR first, last, entry;
int failrc, entrysize;
if (match_data->matchedby == PCRE2_MATCHEDBY_DFA_INTERPRETER)
return PCRE2_ERROR_DFA_UFUNC;
entrysize = pcre2_substring_nametable_scan(match_data->code, stringname,
&first, &last);
if (entrysize < 0) return entrysize;
failrc = PCRE2_ERROR_UNAVAILABLE;
for (entry = first; entry <= last; entry += entrysize)
{
uint32_t n = GET2(entry, 0);
if (n < match_data->oveccount)
{
if (match_data->ovector[n*2] != PCRE2_UNSET)
return pcre2_substring_copy_bynumber(match_data, n, buffer, sizeptr);
failrc = PCRE2_ERROR_UNSET;
}
}
return failrc;
}
/*************************************************
* Copy numbered captured string to given buffer *
*************************************************/
/* This function copies a single captured substring into a given buffer,
identifying it by number.
Arguments:
match_data points to the match data
stringnumber the number of the required substring
buffer where to put the substring
sizeptr the size of the buffer, updated to the size of the substring
Returns: if successful: 0
if not successful, a negative error code:
PCRE2_ERROR_NOMEMORY: buffer too small
PCRE2_ERROR_NOSUBSTRING: no such substring
PCRE2_ERROR_UNAVAILABLE: ovector too small
PCRE2_ERROR_UNSET: substring is not set
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_copy_bynumber(pcre2_match_data *match_data,
uint32_t stringnumber, PCRE2_UCHAR *buffer, PCRE2_SIZE *sizeptr)
{
int rc;
PCRE2_SIZE size;
rc = pcre2_substring_length_bynumber(match_data, stringnumber, &size);
if (rc < 0) return rc;
if (size + 1 > *sizeptr) return PCRE2_ERROR_NOMEMORY;
memcpy(buffer, match_data->subject + match_data->ovector[stringnumber*2],
CU2BYTES(size));
buffer[size] = 0;
*sizeptr = size;
return 0;
}
/*************************************************
* Extract named captured string *
*************************************************/
/* This function copies a single captured substring, identified by name, into
new memory. If the regex permits duplicate names, the first substring that is
set is chosen.
Arguments:
match_data pointer to match_data
stringname the name of the required substring
stringptr where to put the pointer to the new memory
sizeptr where to put the length of the substring
Returns: if successful: zero
if not successful, a negative value:
(1) an error from nametable_scan()
(2) an error from get_bynumber()
(3) PCRE2_ERROR_UNAVAILABLE: no group is in ovector
(4) PCRE2_ERROR_UNSET: all named groups in ovector are unset
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_get_byname(pcre2_match_data *match_data,
PCRE2_SPTR stringname, PCRE2_UCHAR **stringptr, PCRE2_SIZE *sizeptr)
{
PCRE2_SPTR first, last, entry;
int failrc, entrysize;
if (match_data->matchedby == PCRE2_MATCHEDBY_DFA_INTERPRETER)
return PCRE2_ERROR_DFA_UFUNC;
entrysize = pcre2_substring_nametable_scan(match_data->code, stringname,
&first, &last);
if (entrysize < 0) return entrysize;
failrc = PCRE2_ERROR_UNAVAILABLE;
for (entry = first; entry <= last; entry += entrysize)
{
uint32_t n = GET2(entry, 0);
if (n < match_data->oveccount)
{
if (match_data->ovector[n*2] != PCRE2_UNSET)
return pcre2_substring_get_bynumber(match_data, n, stringptr, sizeptr);
failrc = PCRE2_ERROR_UNSET;
}
}
return failrc;
}
/*************************************************
* Extract captured string to new memory *
*************************************************/
/* This function copies a single captured substring into a piece of new
memory.
Arguments:
match_data points to match data
stringnumber the number of the required substring
stringptr where to put a pointer to the new memory
sizeptr where to put the size of the substring
Returns: if successful: 0
if not successful, a negative error code:
PCRE2_ERROR_NOMEMORY: failed to get memory
PCRE2_ERROR_NOSUBSTRING: no such substring
PCRE2_ERROR_UNAVAILABLE: ovector too small
PCRE2_ERROR_UNSET: substring is not set
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_get_bynumber(pcre2_match_data *match_data,
uint32_t stringnumber, PCRE2_UCHAR **stringptr, PCRE2_SIZE *sizeptr)
{
int rc;
PCRE2_SIZE size;
PCRE2_UCHAR *yield;
rc = pcre2_substring_length_bynumber(match_data, stringnumber, &size);
if (rc < 0) return rc;
yield = PRIV(memctl_malloc)(sizeof(pcre2_memctl) +
(size + 1)*PCRE2_CODE_UNIT_WIDTH, (pcre2_memctl *)match_data);
if (yield == NULL) return PCRE2_ERROR_NOMEMORY;
yield = (PCRE2_UCHAR *)(((char *)yield) + sizeof(pcre2_memctl));
memcpy(yield, match_data->subject + match_data->ovector[stringnumber*2],
CU2BYTES(size));
yield[size] = 0;
*stringptr = yield;
*sizeptr = size;
return 0;
}
/*************************************************
* Free memory obtained by get_substring *
*************************************************/
/*
Argument: the result of a previous pcre2_substring_get_byxxx()
Returns: nothing
*/
PCRE2_EXP_DEFN void PCRE2_CALL_CONVENTION
pcre2_substring_free(PCRE2_UCHAR *string)
{
if (string != NULL)
{
pcre2_memctl *memctl = (pcre2_memctl *)((char *)string - sizeof(pcre2_memctl));
memctl->free(memctl, memctl->memory_data);
}
}
/*************************************************
* Get length of a named substring *
*************************************************/
/* This function returns the length of a named captured substring. If the regex
permits duplicate names, the first substring that is set is chosen.
Arguments:
match_data pointer to match data
stringname the name of the required substring
sizeptr where to put the length
Returns: 0 if successful, else a negative error number
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_length_byname(pcre2_match_data *match_data,
PCRE2_SPTR stringname, PCRE2_SIZE *sizeptr)
{
PCRE2_SPTR first, last, entry;
int failrc, entrysize;
if (match_data->matchedby == PCRE2_MATCHEDBY_DFA_INTERPRETER)
return PCRE2_ERROR_DFA_UFUNC;
entrysize = pcre2_substring_nametable_scan(match_data->code, stringname,
&first, &last);
if (entrysize < 0) return entrysize;
failrc = PCRE2_ERROR_UNAVAILABLE;
for (entry = first; entry <= last; entry += entrysize)
{
uint32_t n = GET2(entry, 0);
if (n < match_data->oveccount)
{
if (match_data->ovector[n*2] != PCRE2_UNSET)
return pcre2_substring_length_bynumber(match_data, n, sizeptr);
failrc = PCRE2_ERROR_UNSET;
}
}
return failrc;
}
/*************************************************
* Get length of a numbered substring *
*************************************************/
/* This function returns the length of a captured substring. If the start is
beyond the end (which can happen when \K is used in an assertion), it sets the
length to zero.
Arguments:
match_data pointer to match data
stringnumber the number of the required substring
sizeptr where to put the length, if not NULL
Returns: if successful: 0
if not successful, a negative error code:
PCRE2_ERROR_NOSUBSTRING: no such substring
PCRE2_ERROR_UNAVAILABLE: ovector is too small
PCRE2_ERROR_UNSET: substring is not set
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_length_bynumber(pcre2_match_data *match_data,
uint32_t stringnumber, PCRE2_SIZE *sizeptr)
{
PCRE2_SIZE left, right;
int count = match_data->rc;
if (count == PCRE2_ERROR_PARTIAL)
{
if (stringnumber > 0) return PCRE2_ERROR_PARTIAL;
count = 0;
}
else if (count < 0) return count; /* Match failed */
if (match_data->matchedby != PCRE2_MATCHEDBY_DFA_INTERPRETER)
{
if (stringnumber > match_data->code->top_bracket)
return PCRE2_ERROR_NOSUBSTRING;
if (stringnumber >= match_data->oveccount)
return PCRE2_ERROR_UNAVAILABLE;
if (match_data->ovector[stringnumber*2] == PCRE2_UNSET)
return PCRE2_ERROR_UNSET;
}
else /* Matched using pcre2_dfa_match() */
{
if (stringnumber >= match_data->oveccount) return PCRE2_ERROR_UNAVAILABLE;
if (count != 0 && stringnumber >= (uint32_t)count) return PCRE2_ERROR_UNSET;
}
left = match_data->ovector[stringnumber*2];
right = match_data->ovector[stringnumber*2+1];
if (sizeptr != NULL) *sizeptr = (left > right)? 0 : right - left;
return 0;
}
/*************************************************
* Extract all captured strings to new memory *
*************************************************/
/* This function gets one chunk of memory and builds a list of pointers and all
the captured substrings in it. A NULL pointer is put on the end of the list.
The substrings are zero-terminated, but also, if the final argument is
non-NULL, a list of lengths is also returned. This allows binary data to be
handled.
Arguments:
match_data points to the match data
listptr set to point to the list of pointers
lengthsptr set to point to the list of lengths (may be NULL)
Returns: if successful: 0
if not successful, a negative error code:
PCRE2_ERROR_NOMEMORY: failed to get memory,
or a match failure code
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_list_get(pcre2_match_data *match_data, PCRE2_UCHAR ***listptr,
PCRE2_SIZE **lengthsptr)
{
int i, count, count2;
PCRE2_SIZE size;
PCRE2_SIZE *lensp;
pcre2_memctl *memp;
PCRE2_UCHAR **listp;
PCRE2_UCHAR *sp;
PCRE2_SIZE *ovector;
if ((count = match_data->rc) < 0) return count; /* Match failed */
if (count == 0) count = match_data->oveccount; /* Ovector too small */
count2 = 2*count;
ovector = match_data->ovector;
size = sizeof(pcre2_memctl) + sizeof(PCRE2_UCHAR *); /* For final NULL */
if (lengthsptr != NULL) size += sizeof(PCRE2_SIZE) * count; /* For lengths */
for (i = 0; i < count2; i += 2)
{
size += sizeof(PCRE2_UCHAR *) + CU2BYTES(1);
if (ovector[i+1] > ovector[i]) size += CU2BYTES(ovector[i+1] - ovector[i]);
}
memp = PRIV(memctl_malloc)(size, (pcre2_memctl *)match_data);
if (memp == NULL) return PCRE2_ERROR_NOMEMORY;
*listptr = listp = (PCRE2_UCHAR **)((char *)memp + sizeof(pcre2_memctl));
lensp = (PCRE2_SIZE *)((char *)listp + sizeof(PCRE2_UCHAR *) * (count + 1));
if (lengthsptr == NULL)
{
sp = (PCRE2_UCHAR *)lensp;
lensp = NULL;
}
else
{
*lengthsptr = lensp;
sp = (PCRE2_UCHAR *)((char *)lensp + sizeof(PCRE2_SIZE) * count);
}
for (i = 0; i < count2; i += 2)
{
size = (ovector[i+1] > ovector[i])? (ovector[i+1] - ovector[i]) : 0;
/* Size == 0 includes the case when the capture is unset. Avoid adding
PCRE2_UNSET to match_data->subject because it overflows, even though with
zero size calling memcpy() is harmless. */
if (size != 0) memcpy(sp, match_data->subject + ovector[i], CU2BYTES(size));
*listp++ = sp;
if (lensp != NULL) *lensp++ = size;
sp += size;
*sp++ = 0;
}
*listp = NULL;
return 0;
}
/*************************************************
* Free memory obtained by substring_list_get *
*************************************************/
/*
Argument: the result of a previous pcre2_substring_list_get()
Returns: nothing
*/
PCRE2_EXP_DEFN void PCRE2_CALL_CONVENTION
pcre2_substring_list_free(PCRE2_SPTR *list)
{
if (list != NULL)
{
pcre2_memctl *memctl = (pcre2_memctl *)((char *)list - sizeof(pcre2_memctl));
memctl->free(memctl, memctl->memory_data);
}
}
/*************************************************
* Find (multiple) entries for named string *
*************************************************/
/* This function scans the nametable for a given name, using binary chop. It
returns either two pointers to the entries in the table, or, if no pointers are
given, the number of a unique group with the given name. If duplicate names are
permitted, and the name is not unique, an error is generated.
Arguments:
code the compiled regex
stringname the name whose entries required
firstptr where to put the pointer to the first entry
lastptr where to put the pointer to the last entry
Returns: PCRE2_ERROR_NOSUBSTRING if the name is not found
otherwise, if firstptr and lastptr are NULL:
a group number for a unique substring
else PCRE2_ERROR_NOUNIQUESUBSTRING
otherwise:
the length of each entry, having set firstptr and lastptr
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_nametable_scan(const pcre2_code *code, PCRE2_SPTR stringname,
PCRE2_SPTR *firstptr, PCRE2_SPTR *lastptr)
{
uint16_t bot = 0;
uint16_t top = code->name_count;
uint16_t entrysize = code->name_entry_size;
PCRE2_SPTR nametable = (PCRE2_SPTR)((char *)code + sizeof(pcre2_real_code));
while (top > bot)
{
uint16_t mid = (top + bot) / 2;
PCRE2_SPTR entry = nametable + entrysize*mid;
int c = PRIV(strcmp)(stringname, entry + IMM2_SIZE);
if (c == 0)
{
PCRE2_SPTR first;
PCRE2_SPTR last;
PCRE2_SPTR lastentry;
lastentry = nametable + entrysize * (code->name_count - 1);
first = last = entry;
while (first > nametable)
{
if (PRIV(strcmp)(stringname, (first - entrysize + IMM2_SIZE)) != 0) break;
first -= entrysize;
}
while (last < lastentry)
{
if (PRIV(strcmp)(stringname, (last + entrysize + IMM2_SIZE)) != 0) break;
last += entrysize;
}
if (firstptr == NULL) return (first == last)?
(int)GET2(entry, 0) : PCRE2_ERROR_NOUNIQUESUBSTRING;
*firstptr = first;
*lastptr = last;
return entrysize;
}
if (c > 0) bot = mid + 1; else top = mid;
}
return PCRE2_ERROR_NOSUBSTRING;
}
/*************************************************
* Find number for named string *
*************************************************/
/* This function is a convenience wrapper for pcre2_substring_nametable_scan()
when it is known that names are unique. If there are duplicate names, it is not
defined which number is returned.
Arguments:
code the compiled regex
stringname the name whose number is required
Returns: the number of the named parenthesis, or a negative number
PCRE2_ERROR_NOSUBSTRING if not found
PCRE2_ERROR_NOUNIQUESUBSTRING if not unique
*/
PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_substring_number_from_name(const pcre2_code *code,
PCRE2_SPTR stringname)
{
return pcre2_substring_nametable_scan(code, stringname, NULL, NULL);
}
/* End of pcre2_substring.c */