// Copyright 2017 The Abseil Authors. // // 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 "absl/strings/substitute.h" #include <algorithm> #include "absl/base/internal/raw_logging.h" #include "absl/strings/ascii.h" #include "absl/strings/escaping.h" #include "absl/strings/internal/resize_uninitialized.h" #include "absl/strings/string_view.h" namespace absl { namespace substitute_internal { void SubstituteAndAppendArray(std::string* output, absl::string_view format, const absl::string_view* args_array, size_t num_args) { // Determine total size needed. size_t size = 0; for (size_t i = 0; i < format.size(); i++) { if (format[i] == '$') { if (i + 1 >= format.size()) { #ifndef NDEBUG ABSL_RAW_LOG(FATAL, "Invalid strings::Substitute() format std::string: \"%s\".", absl::CEscape(format).c_str()); #endif return; } else if (absl::ascii_isdigit(format[i + 1])) { int index = format[i + 1] - '0'; if (static_cast<size_t>(index) >= num_args) { #ifndef NDEBUG ABSL_RAW_LOG( FATAL, "Invalid strings::Substitute() format std::string: asked for \"$" "%d\", but only %d args were given. Full format std::string was: " "\"%s\".", index, static_cast<int>(num_args), absl::CEscape(format).c_str()); #endif return; } size += args_array[index].size(); ++i; // Skip next char. } else if (format[i + 1] == '$') { ++size; ++i; // Skip next char. } else { #ifndef NDEBUG ABSL_RAW_LOG(FATAL, "Invalid strings::Substitute() format std::string: \"%s\".", absl::CEscape(format).c_str()); #endif return; } } else { ++size; } } if (size == 0) return; // Build the std::string. size_t original_size = output->size(); strings_internal::STLStringResizeUninitialized(output, original_size + size); char* target = &(*output)[original_size]; for (size_t i = 0; i < format.size(); i++) { if (format[i] == '$') { if (absl::ascii_isdigit(format[i + 1])) { const absl::string_view src = args_array[format[i + 1] - '0']; target = std::copy(src.begin(), src.end(), target); ++i; // Skip next char. } else if (format[i + 1] == '$') { *target++ = '$'; ++i; // Skip next char. } } else { *target++ = format[i]; } } assert(target == output->data() + output->size()); } static const char kHexDigits[] = "0123456789abcdef"; Arg::Arg(const void* value) { static_assert(sizeof(scratch_) >= sizeof(value) * 2 + 2, "fix sizeof(scratch_)"); if (value == nullptr) { piece_ = "NULL"; } else { char* ptr = scratch_ + sizeof(scratch_); uintptr_t num = reinterpret_cast<uintptr_t>(value); do { *--ptr = kHexDigits[num & 0xf]; num >>= 4; } while (num != 0); *--ptr = 'x'; *--ptr = '0'; piece_ = absl::string_view(ptr, scratch_ + sizeof(scratch_) - ptr); } } // TODO(jorg): Don't duplicate so much code between here and str_cat.cc Arg::Arg(Hex hex) { char* const end = &scratch_[numbers_internal::kFastToBufferSize]; char* writer = end; uint64_t value = hex.value; do { *--writer = kHexDigits[value & 0xF]; value >>= 4; } while (value != 0); char* beg; if (end - writer < hex.width) { beg = end - hex.width; std::fill_n(beg, writer - beg, hex.fill); } else { beg = writer; } piece_ = absl::string_view(beg, end - beg); } // TODO(jorg): Don't duplicate so much code between here and str_cat.cc Arg::Arg(Dec dec) { assert(dec.width <= numbers_internal::kFastToBufferSize); char* const end = &scratch_[numbers_internal::kFastToBufferSize]; char* const minfill = end - dec.width; char* writer = end; uint64_t value = dec.value; bool neg = dec.neg; while (value > 9) { *--writer = '0' + (value % 10); value /= 10; } *--writer = '0' + value; if (neg) *--writer = '-'; ptrdiff_t fillers = writer - minfill; if (fillers > 0) { // Tricky: if the fill character is ' ', then it's <fill><+/-><digits> // But...: if the fill character is '0', then it's <+/-><fill><digits> bool add_sign_again = false; if (neg && dec.fill == '0') { // If filling with '0', ++writer; // ignore the sign we just added add_sign_again = true; // and re-add the sign later. } writer -= fillers; std::fill_n(writer, fillers, dec.fill); if (add_sign_again) *--writer = '-'; } piece_ = absl::string_view(writer, end - writer); } } // namespace substitute_internal } // namespace absl