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author | Takuto Ikuta <tikuta@google.com> | 2017-04-26 07:10:27 (GMT) |
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committer | Takuto Ikuta <tikuta@google.com> | 2017-04-26 08:27:54 (GMT) |
commit | 08a3220bc2fe12e7f05967b317d221e0bc620be9 (patch) | |
tree | 3bf56ac3ae430b6e5c66e3bb93b74eec2f1db4f0 /src/string_piece_util.cc | |
parent | 586bb6daef38b3657ba917eb3d7f07ba80c72cd7 (diff) | |
download | Ninja-08a3220bc2fe12e7f05967b317d221e0bc620be9.zip Ninja-08a3220bc2fe12e7f05967b317d221e0bc620be9.tar.gz Ninja-08a3220bc2fe12e7f05967b317d221e0bc620be9.tar.bz2 |
Add string_piece_util
Following functions are implemented for further performance
optimization.
* JoinStringPiece
* SplitStringPiece
* EqualsCaseInsensitiveASCII
* ToLowerASCII
To improve performance of CLParser, I will introduce above functions
into include_normalize-win32.cc.
Diffstat (limited to 'src/string_piece_util.cc')
-rw-r--r-- | src/string_piece_util.cc | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/src/string_piece_util.cc b/src/string_piece_util.cc new file mode 100644 index 0000000..8e1ecfd --- /dev/null +++ b/src/string_piece_util.cc @@ -0,0 +1,78 @@ +// Copyright 2017 Google Inc. All Rights Reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include "string_piece_util.h" + +#include <algorithm> +#include <string> +#include <vector> +using namespace std; + +vector<StringPiece> SplitStringPiece(StringPiece input, char sep) { + vector<StringPiece> elems; + elems.reserve(count(input.begin(), input.end(), sep) + 1); + + StringPiece::const_iterator pos = input.begin(); + + for (;;) { + const char* next_pos = find(pos, input.end(), sep); + if (next_pos == input.end()) { + elems.push_back(StringPiece(pos, input.end() - pos)); + break; + } + elems.push_back(StringPiece(pos, next_pos - pos)); + pos = next_pos + 1; + } + + return elems; +} + +string JoinStringPiece(const vector<StringPiece>& list, char sep) { + if (list.size() == 0){ + return ""; + } + + string ret; + + { + size_t cap = list.size() - 1; + for (size_t i = 0; i < list.size(); ++i) { + cap += list[i].len_; + } + ret.reserve(cap); + } + + for (size_t i = 0; i < list.size(); ++i) { + if (i != 0) { + ret += sep; + } + ret.append(list[i].str_, list[i].len_); + } + + return ret; +} + +bool EqualsCaseInsensitiveASCII(StringPiece a, StringPiece b) { + if (a.len_ != b.len_) { + return false; + } + + for (size_t i = 0; i < a.len_; ++i) { + if (ToLowerASCII(a.str_[i]) != ToLowerASCII(b.str_[i])) { + return false; + } + } + + return true; +} |