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// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/strings/string_split.h"
#include <stddef.h>
#include "base/logging.h"
#include "base/strings/string_util.h"
#include "base/third_party/icu/icu_utf.h"
namespace base {
namespace {
// Returns either the ASCII or UTF-16 whitespace.
template<typename Str> BasicStringPiece<Str> WhitespaceForType();
#if defined(OS_WIN) && defined(BASE_STRING16_IS_STD_U16STRING)
template <>
WStringPiece WhitespaceForType<std::wstring>() {
return kWhitespaceWide;
}
#endif
template<> StringPiece16 WhitespaceForType<string16>() {
return kWhitespaceUTF16;
}
template<> StringPiece WhitespaceForType<std::string>() {
return kWhitespaceASCII;
}
// General string splitter template. Can take 8- or 16-bit input, can produce
// the corresponding string or StringPiece output.
template <typename OutputStringType, typename Str>
static std::vector<OutputStringType> SplitStringT(
BasicStringPiece<Str> str,
BasicStringPiece<Str> delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
std::vector<OutputStringType> result;
if (str.empty())
return result;
size_t start = 0;
while (start != Str::npos) {
size_t end = str.find_first_of(delimiter, start);
BasicStringPiece<Str> piece;
if (end == Str::npos) {
piece = str.substr(start);
start = Str::npos;
} else {
piece = str.substr(start, end - start);
start = end + 1;
}
if (whitespace == TRIM_WHITESPACE)
piece = TrimString(piece, WhitespaceForType<Str>(), TRIM_ALL);
if (result_type == SPLIT_WANT_ALL || !piece.empty())
result.emplace_back(piece);
}
return result;
}
bool AppendStringKeyValue(StringPiece input,
char delimiter,
StringPairs* result) {
// Always append a new item regardless of success (it might be empty). The
// below code will copy the strings directly into the result pair.
result->resize(result->size() + 1);
auto& result_pair = result->back();
// Find the delimiter.
size_t end_key_pos = input.find_first_of(delimiter);
if (end_key_pos == std::string::npos) {
DVLOG(1) << "cannot find delimiter in: " << input;
return false; // No delimiter.
}
result_pair.first = std::string(input.substr(0, end_key_pos));
// Find the value string.
StringPiece remains = input.substr(end_key_pos, input.size() - end_key_pos);
size_t begin_value_pos = remains.find_first_not_of(delimiter);
if (begin_value_pos == StringPiece::npos) {
DVLOG(1) << "cannot parse value from input: " << input;
return false; // No value.
}
result_pair.second = std::string(
remains.substr(begin_value_pos, remains.size() - begin_value_pos));
return true;
}
template <typename OutputStringType, typename Str>
std::vector<OutputStringType> SplitStringUsingSubstrT(
BasicStringPiece<Str> input,
BasicStringPiece<Str> delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
using Piece = BasicStringPiece<Str>;
using size_type = typename Piece::size_type;
std::vector<OutputStringType> result;
for (size_type begin_index = 0, end_index = 0; end_index != Piece::npos;
begin_index = end_index + delimiter.size()) {
end_index = input.find(delimiter, begin_index);
Piece term = end_index == Piece::npos
? input.substr(begin_index)
: input.substr(begin_index, end_index - begin_index);
if (whitespace == TRIM_WHITESPACE)
term = TrimString(term, WhitespaceForType<Str>(), TRIM_ALL);
if (result_type == SPLIT_WANT_ALL || !term.empty())
result.emplace_back(term);
}
return result;
}
} // namespace
std::vector<std::string> SplitString(StringPiece input,
StringPiece separators,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringT<std::string>(input, separators, whitespace, result_type);
}
std::vector<string16> SplitString(StringPiece16 input,
StringPiece16 separators,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringT<string16>(input, separators, whitespace, result_type);
}
std::vector<StringPiece> SplitStringPiece(StringPiece input,
StringPiece separators,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringT<StringPiece>(input, separators, whitespace, result_type);
}
std::vector<StringPiece16> SplitStringPiece(StringPiece16 input,
StringPiece16 separators,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringT<StringPiece16>(input, separators, whitespace,
result_type);
}
bool SplitStringIntoKeyValuePairs(StringPiece input,
char key_value_delimiter,
char key_value_pair_delimiter,
StringPairs* key_value_pairs) {
return SplitStringIntoKeyValuePairsUsingSubstr(
input, key_value_delimiter, StringPiece(&key_value_pair_delimiter, 1),
key_value_pairs);
}
bool SplitStringIntoKeyValuePairsUsingSubstr(
StringPiece input,
char key_value_delimiter,
StringPiece key_value_pair_delimiter,
StringPairs* key_value_pairs) {
key_value_pairs->clear();
std::vector<StringPiece> pairs = SplitStringPieceUsingSubstr(
input, key_value_pair_delimiter, TRIM_WHITESPACE, SPLIT_WANT_NONEMPTY);
key_value_pairs->reserve(pairs.size());
bool success = true;
for (const StringPiece& pair : pairs) {
if (!AppendStringKeyValue(pair, key_value_delimiter, key_value_pairs)) {
// Don't return here, to allow for pairs without associated
// value or key; just record that the split failed.
success = false;
}
}
return success;
}
std::vector<string16> SplitStringUsingSubstr(StringPiece16 input,
StringPiece16 delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringUsingSubstrT<string16>(input, delimiter, whitespace,
result_type);
}
std::vector<std::string> SplitStringUsingSubstr(StringPiece input,
StringPiece delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringUsingSubstrT<std::string>(input, delimiter, whitespace,
result_type);
}
std::vector<StringPiece16> SplitStringPieceUsingSubstr(
StringPiece16 input,
StringPiece16 delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
std::vector<StringPiece16> result;
return SplitStringUsingSubstrT<StringPiece16>(input, delimiter, whitespace,
result_type);
}
std::vector<StringPiece> SplitStringPieceUsingSubstr(
StringPiece input,
StringPiece delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringUsingSubstrT<StringPiece>(input, delimiter, whitespace,
result_type);
}
#if defined(OS_WIN) && defined(BASE_STRING16_IS_STD_U16STRING)
std::vector<std::wstring> SplitString(WStringPiece input,
WStringPiece separators,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringT<std::wstring>(input, separators, whitespace, result_type);
}
std::vector<WStringPiece> SplitStringPiece(WStringPiece input,
WStringPiece separators,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringT<WStringPiece>(input, separators, whitespace, result_type);
}
std::vector<std::wstring> SplitStringUsingSubstr(WStringPiece input,
WStringPiece delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringUsingSubstrT<std::wstring>(input, delimiter, whitespace,
result_type);
}
std::vector<WStringPiece> SplitStringPieceUsingSubstr(
WStringPiece input,
WStringPiece delimiter,
WhitespaceHandling whitespace,
SplitResult result_type) {
return SplitStringUsingSubstrT<WStringPiece>(input, delimiter, whitespace,
result_type);
}
#endif
} // namespace base