/tags/harbour-1.0.0/source/hbpcre/pcretryf.c
C | 137 lines | 45 code | 19 blank | 73 comment | 6 complexity | 40d7e127f4c2b4dd43b7bc500769d32e MD5 | raw file
Possible License(s): AGPL-1.0, BSD-3-Clause, CC-BY-SA-3.0, LGPL-3.0, GPL-2.0, LGPL-2.0, LGPL-2.1
- /*************************************************
- * 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
- Copyright (c) 1997-2008 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.
- -----------------------------------------------------------------------------
- */
- /* This module contains an internal function that tests a compiled pattern to
- see if it was compiled with the opposite endianness. If so, it uses an
- auxiliary local function to flip the appropriate bytes. */
- #if 1
- #include "_hbconf.h"
- #endif
- #include "pcreinal.h"
- /*************************************************
- * Flip bytes in an integer *
- *************************************************/
- /* This function is called when the magic number in a regex doesn't match, in
- order to flip its bytes to see if we are dealing with a pattern that was
- compiled on a host of different endianness. If so, this function is used to
- flip other byte values.
- Arguments:
- value the number to flip
- n the number of bytes to flip (assumed to be 2 or 4)
- Returns: the flipped value
- */
- static unsigned long int
- byteflip(unsigned long int value, int n)
- {
- if (n == 2) return ((value & 0x00ff) << 8) | ((value & 0xff00) >> 8);
- return ((value & 0x000000ff) << 24) |
- ((value & 0x0000ff00) << 8) |
- ((value & 0x00ff0000) >> 8) |
- ((value & 0xff000000) >> 24);
- }
- /*************************************************
- * Test for a byte-flipped compiled regex *
- *************************************************/
- /* This function is called from pcre_exec(), pcre_dfa_exec(), and also from
- pcre_fullinfo(). Its job is to test whether the regex is byte-flipped - that
- is, it was compiled on a system of opposite endianness. The function is called
- only when the native MAGIC_NUMBER test fails. If the regex is indeed flipped,
- we flip all the relevant values into a different data block, and return it.
- Arguments:
- re points to the regex
- study points to study data, or NULL
- internal_re points to a new regex block
- internal_study points to a new study block
- Returns: the new block if is is indeed a byte-flipped regex
- NULL if it is not
- */
- real_pcre *
- _pcre_try_flipped(const real_pcre *re, real_pcre *internal_re,
- const pcre_study_data *study, pcre_study_data *internal_study)
- {
- if (byteflip(re->magic_number, sizeof(re->magic_number)) != MAGIC_NUMBER)
- return NULL;
- *internal_re = *re; /* To copy other fields */
- internal_re->size = byteflip(re->size, sizeof(re->size));
- internal_re->options = byteflip(re->options, sizeof(re->options));
- internal_re->flags = (pcre_uint16)byteflip(re->flags, sizeof(re->flags));
- internal_re->top_bracket =
- (pcre_uint16)byteflip(re->top_bracket, sizeof(re->top_bracket));
- internal_re->top_backref =
- (pcre_uint16)byteflip(re->top_backref, sizeof(re->top_backref));
- internal_re->first_byte =
- (pcre_uint16)byteflip(re->first_byte, sizeof(re->first_byte));
- internal_re->req_byte =
- (pcre_uint16)byteflip(re->req_byte, sizeof(re->req_byte));
- internal_re->name_table_offset =
- (pcre_uint16)byteflip(re->name_table_offset, sizeof(re->name_table_offset));
- internal_re->name_entry_size =
- (pcre_uint16)byteflip(re->name_entry_size, sizeof(re->name_entry_size));
- internal_re->name_count =
- (pcre_uint16)byteflip(re->name_count, sizeof(re->name_count));
- if (study != NULL)
- {
- *internal_study = *study; /* To copy other fields */
- internal_study->size = byteflip(study->size, sizeof(study->size));
- internal_study->options = byteflip(study->options, sizeof(study->options));
- }
- return internal_re;
- }
- /* End of pcre_tryflipped.c */