From 84adefa331c4159d432d22840663c38f155cd4c1 Mon Sep 17 00:00:00 2001 From: Erlang/OTP Date: Fri, 20 Nov 2009 14:54:40 +0000 Subject: The R13B03 release. --- erts/emulator/pcre/pcre_try_flipped.c | 138 ++++++++++++++++++++++++++++++++++ 1 file changed, 138 insertions(+) create mode 100644 erts/emulator/pcre/pcre_try_flipped.c (limited to 'erts/emulator/pcre/pcre_try_flipped.c') diff --git a/erts/emulator/pcre/pcre_try_flipped.c b/erts/emulator/pcre/pcre_try_flipped.c new file mode 100644 index 0000000000..7b6c85cb26 --- /dev/null +++ b/erts/emulator/pcre/pcre_try_flipped.c @@ -0,0 +1,138 @@ +/************************************************* +* 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. */ + +/* %ExternalCopyright% */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "pcre_internal.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 * +_erts_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 */ -- cgit v1.2.3