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// 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
//
//
// 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 <cassert>
#include <cstddef>
#include <cstdint>
#include <string>
#include "absl/base/config.h"
#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/numbers.h"
#include "absl/strings/str_cat.h"
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
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] == '$') {
if (i + 1 >= format.size()) {
#ifndef NDEBUG
ABSL_RAW_LOG(FATAL,
"Invalid absl::Substitute() format string: \"%s\".",
absl::CEscape(format).c_str());
#endif
return;
} else if (absl::ascii_isdigit(
static_cast<unsigned char>(format[i + 1]))) {
int index = format[i + 1] - '0';
if (static_cast<size_t>(index) >= num_args) {
#ifndef NDEBUG
ABSL_RAW_LOG(
FATAL,
"Invalid absl::Substitute() format string: asked for \"$"
"%d\", but only %d args were given. Full format 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] == '$') {
++size;
++i; // Skip next char.
} else {
#ifndef NDEBUG
ABSL_RAW_LOG(FATAL,
"Invalid absl::Substitute() format string: \"%s\".",
absl::CEscape(format).c_str());
#endif
return;
}
} else {
++size;
}
}
if (size == 0) return;
// Build the string.
size_t original_size = output->size();
strings_internal::STLStringResizeUninitializedAmortized(output,
original_size + size);
char* target = &(*output)[original_size];
for (size_t i = 0; i < format.size(); i++) {
if (format[i] == '$') {
if (absl::ascii_isdigit(static_cast<unsigned char>(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());
}
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 = absl::numbers_internal::kHexChar[num & 0xf];
num >>= 4;
} while (num != 0);
*--ptr = 'x';
*--ptr = '0';
piece_ = absl::string_view(
ptr, static_cast<size_t>(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 = absl::numbers_internal::kHexChar[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, static_cast<size_t>(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' + static_cast<char>(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, static_cast<size_t>(end - writer));
}
} // namespace substitute_internal
ABSL_NAMESPACE_END
} // namespace absl