From d7cae12696b96500c05dd2d430f6238922c20c96 Mon Sep 17 00:00:00 2001 From: "initial.commit" Date: Sat, 26 Jul 2008 21:49:38 +0000 Subject: Add base to the repository. git-svn-id: svn://svn.chromium.org/chrome/trunk/src@8 0039d316-1c4b-4281-b951-d872f2087c98 --- base/string_piece.cc | 240 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 240 insertions(+) create mode 100644 base/string_piece.cc (limited to 'base/string_piece.cc') diff --git a/base/string_piece.cc b/base/string_piece.cc new file mode 100644 index 0000000..e2c0aa7 --- /dev/null +++ b/base/string_piece.cc @@ -0,0 +1,240 @@ +// Copyright 2008, Google Inc. +// All rights reserved. +// +// 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 Google Inc. 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. +// Copied from strings/stringpiece.cc with modifications + +#include +#include + +#include "base/string_piece.h" + +typedef StringPiece::size_type size_type; + +std::ostream& operator<<(std::ostream& o, const StringPiece& piece) { + o.write(piece.data(), static_cast(piece.size())); + return o; +} + +bool operator==(const StringPiece& x, const StringPiece& y) { + if (x.size() != y.size()) + return false; + + return StringPiece::wordmemcmp(x.data(), y.data(), x.size()) == 0; +} + +void StringPiece::CopyToString(std::string* target) const { + target->assign(!empty() ? data() : "", size()); +} + +void StringPiece::AppendToString(std::string* target) const { + if (!empty()) + target->append(data(), size()); +} + +size_type StringPiece::copy(char* buf, size_type n, size_type pos) const { + size_type ret = std::min(length_ - pos, n); + memcpy(buf, ptr_ + pos, ret); + return ret; +} + +size_type StringPiece::find(const StringPiece& s, size_type pos) const { + if (pos > length_) + return npos; + + const char* result = std::search(ptr_ + pos, ptr_ + length_, + s.ptr_, s.ptr_ + s.length_); + const size_type xpos = result - ptr_; + return xpos + s.length_ <= length_ ? xpos : npos; +} + +size_type StringPiece::find(char c, size_type pos) const { + if (pos >= length_) + return npos; + + const char* result = std::find(ptr_ + pos, ptr_ + length_, c); + return result != ptr_ + length_ ? result - ptr_ : npos; +} + +size_type StringPiece::rfind(const StringPiece& s, size_type pos) const { + if (length_ < s.length_) + return npos; + + if (s.empty()) + return std::min(length_, pos); + + const char* last = ptr_ + std::min(length_ - s.length_, pos) + s.length_; + const char* result = std::find_end(ptr_, last, s.ptr_, s.ptr_ + s.length_); + return result != last ? result - ptr_ : npos; +} + +size_type StringPiece::rfind(char c, size_type pos) const { + if (length_ == 0) + return npos; + + for (size_type i = std::min(pos, length_ - 1); ; --i) { + if (ptr_[i] == c) + return i; + if (i == 0) + break; + } + return npos; +} + +// For each character in characters_wanted, sets the index corresponding +// to the ASCII code of that character to 1 in table. This is used by +// the find_.*_of methods below to tell whether or not a character is in +// the lookup table in constant time. +// The argument `table' must be an array that is large enough to hold all +// the possible values of an unsigned char. Thus it should be be declared +// as follows: +// bool table[UCHAR_MAX + 1] +static inline void BuildLookupTable(const StringPiece& characters_wanted, + bool* table) { + const size_type length = characters_wanted.length(); + const char* const data = characters_wanted.data(); + for (size_type i = 0; i < length; ++i) { + table[static_cast(data[i])] = true; + } +} + +size_type StringPiece::find_first_of(const StringPiece& s, + size_type pos) const { + if (length_ == 0 || s.length_ == 0) + return npos; + + // Avoid the cost of BuildLookupTable() for a single-character search. + if (s.length_ == 1) + return find_first_of(s.ptr_[0], pos); + + bool lookup[UCHAR_MAX + 1] = { false }; + BuildLookupTable(s, lookup); + for (size_type i = pos; i < length_; ++i) { + if (lookup[static_cast(ptr_[i])]) { + return i; + } + } + return npos; +} + +size_type StringPiece::find_first_not_of(const StringPiece& s, + size_type pos) const { + if (length_ == 0) + return npos; + + if (s.length_ == 0) + return 0; + + // Avoid the cost of BuildLookupTable() for a single-character search. + if (s.length_ == 1) + return find_first_not_of(s.ptr_[0], pos); + + bool lookup[UCHAR_MAX + 1] = { false }; + BuildLookupTable(s, lookup); + for (size_type i = pos; i < length_; ++i) { + if (!lookup[static_cast(ptr_[i])]) { + return i; + } + } + return npos; +} + +size_type StringPiece::find_first_not_of(char c, size_type pos) const { + if (length_ == 0) + return npos; + + for (; pos < length_; ++pos) { + if (ptr_[pos] != c) { + return pos; + } + } + return npos; +} + +size_type StringPiece::find_last_of(const StringPiece& s, size_type pos) const { + if (length_ == 0 || s.length_ == 0) + return npos; + + // Avoid the cost of BuildLookupTable() for a single-character search. + if (s.length_ == 1) + return find_last_of(s.ptr_[0], pos); + + bool lookup[UCHAR_MAX + 1] = { false }; + BuildLookupTable(s, lookup); + for (size_type i = std::min(pos, length_ - 1); ; --i) { + if (lookup[static_cast(ptr_[i])]) + return i; + if (i == 0) + break; + } + return npos; +} + +size_type StringPiece::find_last_not_of(const StringPiece& s, + size_type pos) const { + if (length_ == 0) + return npos; + + size_type i = std::min(pos, length_ - 1); + if (s.length_ == 0) + return i; + + // Avoid the cost of BuildLookupTable() for a single-character search. + if (s.length_ == 1) + return find_last_not_of(s.ptr_[0], pos); + + bool lookup[UCHAR_MAX + 1] = { false }; + BuildLookupTable(s, lookup); + for (; ; --i) { + if (!lookup[static_cast(ptr_[i])]) + return i; + if (i == 0) + break; + } + return npos; +} + +size_type StringPiece::find_last_not_of(char c, size_type pos) const { + if (length_ == 0) + return npos; + + for (size_type i = std::min(pos, length_ - 1); ; --i) { + if (ptr_[i] != c) + return i; + if (i == 0) + break; + } + return npos; +} + +StringPiece StringPiece::substr(size_type pos, size_type n) const { + if (pos > length_) pos = length_; + if (n > length_ - pos) n = length_ - pos; + return StringPiece(ptr_ + pos, n); +} + +const StringPiece::size_type StringPiece::npos = size_type(-1); -- cgit v1.1