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/*
* Copyright 2012-present Facebook, Inc.
*
* 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 <folly/String.h>
#include <cctype>
#include <cerrno>
#include <cstdarg>
#include <cstring>
#include <iterator>
#include <stdexcept>
#include <glog/logging.h>
#include <folly/ScopeGuard.h>
namespace folly {
static_assert(IsConvertible<float>::value, "");
static_assert(IsConvertible<int>::value, "");
static_assert(IsConvertible<bool>::value, "");
static_assert(IsConvertible<int>::value, "");
static_assert(!IsConvertible<std::vector<int>>::value, "");
static inline bool is_oddspace(char c) {
return c == '\n' || c == '\t' || c == '\r';
}
StringPiece ltrimWhitespace(StringPiece sp) {
// Spaces other than ' ' characters are less common but should be
// checked. This configuration where we loop on the ' '
// separately from oddspaces was empirically fastest.
loop:
for (; !sp.empty() && sp.front() == ' '; sp.pop_front()) {
}
if (!sp.empty() && is_oddspace(sp.front())) {
sp.pop_front();
goto loop;
}
return sp;
}
StringPiece rtrimWhitespace(StringPiece sp) {
// Spaces other than ' ' characters are less common but should be
// checked. This configuration where we loop on the ' '
// separately from oddspaces was empirically fastest.
loop:
for (; !sp.empty() && sp.back() == ' '; sp.pop_back()) {
}
if (!sp.empty() && is_oddspace(sp.back())) {
sp.pop_back();
goto loop;
}
return sp;
}
namespace {
int stringAppendfImplHelper(char* buf,
size_t bufsize,
const char* format,
va_list args) {
va_list args_copy;
va_copy(args_copy, args);
int bytes_used = vsnprintf(buf, bufsize, format, args_copy);
va_end(args_copy);
return bytes_used;
}
void stringAppendfImpl(std::string& output, const char* format, va_list args) {
// Very simple; first, try to avoid an allocation by using an inline
// buffer. If that fails to hold the output string, allocate one on
// the heap, use it instead.
//
// It is hard to guess the proper size of this buffer; some
// heuristics could be based on the number of format characters, or
// static analysis of a codebase. Or, we can just pick a number
// that seems big enough for simple cases (say, one line of text on
// a terminal) without being large enough to be concerning as a
// stack variable.
std::array<char, 128> inline_buffer;
int bytes_used = stringAppendfImplHelper(
inline_buffer.data(), inline_buffer.size(), format, args);
if (bytes_used < 0) {
throw std::runtime_error(to<std::string>(
"Invalid format string; snprintf returned negative "
"with format string: ",
format));
}
if (static_cast<size_t>(bytes_used) < inline_buffer.size()) {
output.append(inline_buffer.data(), size_t(bytes_used));
return;
}
// Couldn't fit. Heap allocate a buffer, oh well.
std::unique_ptr<char[]> heap_buffer(new char[size_t(bytes_used + 1)]);
int final_bytes_used = stringAppendfImplHelper(
heap_buffer.get(), size_t(bytes_used + 1), format, args);
// The second call can take fewer bytes if, for example, we were printing a
// string buffer with null-terminating char using a width specifier -
// vsnprintf("%.*s", buf.size(), buf)
CHECK(bytes_used >= final_bytes_used);
// We don't keep the trailing '\0' in our output string
output.append(heap_buffer.get(), size_t(final_bytes_used));
}
} // namespace
std::string stringPrintf(const char* format, ...) {
va_list ap;
va_start(ap, format);
SCOPE_EXIT {
va_end(ap);
};
return stringVPrintf(format, ap);
}
std::string stringVPrintf(const char* format, va_list ap) {
std::string ret;
stringAppendfImpl(ret, format, ap);
return ret;
}
// Basic declarations; allow for parameters of strings and string
// pieces to be specified.
std::string& stringAppendf(std::string* output, const char* format, ...) {
va_list ap;
va_start(ap, format);
SCOPE_EXIT {
va_end(ap);
};
return stringVAppendf(output, format, ap);
}
std::string& stringVAppendf(std::string* output,
const char* format,
va_list ap) {
stringAppendfImpl(*output, format, ap);
return *output;
}
void stringPrintf(std::string* output, const char* format, ...) {
va_list ap;
va_start(ap, format);
SCOPE_EXIT {
va_end(ap);
};
return stringVPrintf(output, format, ap);
}
void stringVPrintf(std::string* output, const char* format, va_list ap) {
output->clear();
stringAppendfImpl(*output, format, ap);
};
namespace {
struct PrettySuffix {
const char* suffix;
double val;
};
const PrettySuffix kPrettyTimeSuffixes[] = {
{ "s ", 1e0L },
{ "ms", 1e-3L },
{ "us", 1e-6L },
{ "ns", 1e-9L },
{ "ps", 1e-12L },
{ "s ", 0 },
{ nullptr, 0 },
};
const PrettySuffix kPrettyBytesMetricSuffixes[] = {
{ "TB", 1e12L },
{ "GB", 1e9L },
{ "MB", 1e6L },
{ "kB", 1e3L },
{ "B ", 0L },
{ nullptr, 0 },
};
const PrettySuffix kPrettyBytesBinarySuffixes[] = {
{ "TB", int64_t(1) << 40 },
{ "GB", int64_t(1) << 30 },
{ "MB", int64_t(1) << 20 },
{ "kB", int64_t(1) << 10 },
{ "B ", 0L },
{ nullptr, 0 },
};
const PrettySuffix kPrettyBytesBinaryIECSuffixes[] = {
{ "TiB", int64_t(1) << 40 },
{ "GiB", int64_t(1) << 30 },
{ "MiB", int64_t(1) << 20 },
{ "KiB", int64_t(1) << 10 },
{ "B ", 0L },
{ nullptr, 0 },
};
const PrettySuffix kPrettyUnitsMetricSuffixes[] = {
{ "tril", 1e12L },
{ "bil", 1e9L },
{ "M", 1e6L },
{ "k", 1e3L },
{ " ", 0 },
{ nullptr, 0 },
};
const PrettySuffix kPrettyUnitsBinarySuffixes[] = {
{ "T", int64_t(1) << 40 },
{ "G", int64_t(1) << 30 },
{ "M", int64_t(1) << 20 },
{ "k", int64_t(1) << 10 },
{ " ", 0 },
{ nullptr, 0 },
};
const PrettySuffix kPrettyUnitsBinaryIECSuffixes[] = {
{ "Ti", int64_t(1) << 40 },
{ "Gi", int64_t(1) << 30 },
{ "Mi", int64_t(1) << 20 },
{ "Ki", int64_t(1) << 10 },
{ " ", 0 },
{ nullptr, 0 },
};
const PrettySuffix kPrettySISuffixes[] = {
{ "Y", 1e24L },
{ "Z", 1e21L },
{ "E", 1e18L },
{ "P", 1e15L },
{ "T", 1e12L },
{ "G", 1e9L },
{ "M", 1e6L },
{ "k", 1e3L },
{ "h", 1e2L },
{ "da", 1e1L },
{ "d", 1e-1L },
{ "c", 1e-2L },
{ "m", 1e-3L },
{ "u", 1e-6L },
{ "n", 1e-9L },
{ "p", 1e-12L },
{ "f", 1e-15L },
{ "a", 1e-18L },
{ "z", 1e-21L },
{ "y", 1e-24L },
{ " ", 0 },
{ nullptr, 0}
};
const PrettySuffix* const kPrettySuffixes[PRETTY_NUM_TYPES] = {
kPrettyTimeSuffixes,
kPrettyBytesMetricSuffixes,
kPrettyBytesBinarySuffixes,
kPrettyBytesBinaryIECSuffixes,
kPrettyUnitsMetricSuffixes,
kPrettyUnitsBinarySuffixes,
kPrettyUnitsBinaryIECSuffixes,
kPrettySISuffixes,
};
} // namespace
std::string prettyPrint(double val, PrettyType type, bool addSpace) {
char buf[100];
// pick the suffixes to use
assert(type >= 0);
assert(type < PRETTY_NUM_TYPES);
const PrettySuffix* suffixes = kPrettySuffixes[type];
// find the first suffix we're bigger than -- then use it
double abs_val = fabs(val);
for (int i = 0; suffixes[i].suffix; ++i) {
if (abs_val >= suffixes[i].val) {
snprintf(buf, sizeof buf, "%.4g%s%s",
(suffixes[i].val ? (val / suffixes[i].val)
: val),
(addSpace ? " " : ""),
suffixes[i].suffix);
return std::string(buf);
}
}
// no suffix, we've got a tiny value -- just print it in sci-notation
snprintf(buf, sizeof buf, "%.4g", val);
return std::string(buf);
}
//TODO:
//1) Benchmark & optimize
double prettyToDouble(folly::StringPiece *const prettyString,
const PrettyType type) {
double value = folly::to<double>(prettyString);
while (prettyString->size() > 0 && std::isspace(prettyString->front())) {
prettyString->advance(1); //Skipping spaces between number and suffix
}
const PrettySuffix* suffixes = kPrettySuffixes[type];
int longestPrefixLen = -1;
int bestPrefixId = -1;
for (int j = 0 ; suffixes[j].suffix; ++j) {
if (suffixes[j].suffix[0] == ' '){//Checking for " " -> number rule.
if (longestPrefixLen == -1) {
longestPrefixLen = 0; //No characters to skip
bestPrefixId = j;
}
} else if (prettyString->startsWith(suffixes[j].suffix)) {
int suffixLen = int(strlen(suffixes[j].suffix));
//We are looking for a longest suffix matching prefix of the string
//after numeric value. We need this in case suffixes have common prefix.
if (suffixLen > longestPrefixLen) {
longestPrefixLen = suffixLen;
bestPrefixId = j;
}
}
}
if (bestPrefixId == -1) { //No valid suffix rule found
throw std::invalid_argument(folly::to<std::string>(
"Unable to parse suffix \"",
prettyString->toString(), "\""));
}
prettyString->advance(size_t(longestPrefixLen));
return suffixes[bestPrefixId].val ? value * suffixes[bestPrefixId].val :
value;
}
double prettyToDouble(folly::StringPiece prettyString, const PrettyType type){
double result = prettyToDouble(&prettyString, type);
detail::enforceWhitespace(prettyString);
return result;
}
std::string hexDump(const void* ptr, size_t size) {
std::ostringstream os;
hexDump(ptr, size, std::ostream_iterator<StringPiece>(os, "\n"));
return os.str();
}
fbstring errnoStr(int err) {
int savedErrno = errno;
// Ensure that we reset errno upon exit.
auto guard(makeGuard([&] { errno = savedErrno; }));
char buf[1024];
buf[0] = '\0';
fbstring result;
// https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man3/strerror_r.3.html
// http://www.kernel.org/doc/man-pages/online/pages/man3/strerror.3.html
#if defined(_WIN32) && (defined(__MINGW32__) || defined(_MSC_VER))
// mingw64 has no strerror_r, but Windows has strerror_s, which C11 added
// as well. So maybe we should use this across all platforms (together
// with strerrorlen_s). Note strerror_r and _s have swapped args.
int r = strerror_s(buf, sizeof(buf), err);
if (r != 0) {
result = to<fbstring>(
"Unknown error ", err,
" (strerror_r failed with error ", errno, ")");
} else {
result.assign(buf);
}
#elif defined(FOLLY_HAVE_XSI_STRERROR_R) || \
defined(__APPLE__) || defined(__ANDROID__)
// Using XSI-compatible strerror_r
int r = strerror_r(err, buf, sizeof(buf));
// OSX/FreeBSD use EINVAL and Linux uses -1 so just check for non-zero
if (r != 0) {
result = to<fbstring>(
"Unknown error ", err,
" (strerror_r failed with error ", errno, ")");
} else {
result.assign(buf);
}
#else
// Using GNU strerror_r
result.assign(strerror_r(err, buf, sizeof(buf)));
#endif
return result;
}
namespace {
void toLowerAscii8(char& c) {
// Branchless tolower, based on the input-rotating trick described
// at http://www.azillionmonkeys.com/qed/asmexample.html
//
// This algorithm depends on an observation: each uppercase
// ASCII character can be converted to its lowercase equivalent
// by adding 0x20.
// Step 1: Clear the high order bit. We'll deal with it in Step 5.
uint8_t rotated = uint8_t(c & 0x7f);
// Currently, the value of rotated, as a function of the original c is:
// below 'A': 0- 64
// 'A'-'Z': 65- 90
// above 'Z': 91-127
// Step 2: Add 0x25 (37)
rotated += 0x25;
// Now the value of rotated, as a function of the original c is:
// below 'A': 37-101
// 'A'-'Z': 102-127
// above 'Z': 128-164
// Step 3: clear the high order bit
rotated &= 0x7f;
// below 'A': 37-101
// 'A'-'Z': 102-127
// above 'Z': 0- 36
// Step 4: Add 0x1a (26)
rotated += 0x1a;
// below 'A': 63-127
// 'A'-'Z': 128-153
// above 'Z': 25- 62
// At this point, note that only the uppercase letters have been
// transformed into values with the high order bit set (128 and above).
// Step 5: Shift the high order bit 2 spaces to the right: the spot
// where the only 1 bit in 0x20 is. But first, how we ignored the
// high order bit of the original c in step 1? If that bit was set,
// we may have just gotten a false match on a value in the range
// 128+'A' to 128+'Z'. To correct this, need to clear the high order
// bit of rotated if the high order bit of c is set. Since we don't
// care about the other bits in rotated, the easiest thing to do
// is invert all the bits in c and bitwise-and them with rotated.
rotated &= ~c;
rotated >>= 2;
// Step 6: Apply a mask to clear everything except the 0x20 bit
// in rotated.
rotated &= 0x20;
// At this point, rotated is 0x20 if c is 'A'-'Z' and 0x00 otherwise
// Step 7: Add rotated to c
c += char(rotated);
}
void toLowerAscii32(uint32_t& c) {
// Besides being branchless, the algorithm in toLowerAscii8() has another
// interesting property: None of the addition operations will cause
// an overflow in the 8-bit value. So we can pack four 8-bit values
// into a uint32_t and run each operation on all four values in parallel
// without having to use any CPU-specific SIMD instructions.
uint32_t rotated = c & uint32_t(0x7f7f7f7fL);
rotated += uint32_t(0x25252525L);
rotated &= uint32_t(0x7f7f7f7fL);
rotated += uint32_t(0x1a1a1a1aL);
// Step 5 involves a shift, so some bits will spill over from each
// 8-bit value into the next. But that's okay, because they're bits
// that will be cleared by the mask in step 6 anyway.
rotated &= ~c;
rotated >>= 2;
rotated &= uint32_t(0x20202020L);
c += rotated;
}
void toLowerAscii64(uint64_t& c) {
// 64-bit version of toLower32
uint64_t rotated = c & uint64_t(0x7f7f7f7f7f7f7f7fL);
rotated += uint64_t(0x2525252525252525L);
rotated &= uint64_t(0x7f7f7f7f7f7f7f7fL);
rotated += uint64_t(0x1a1a1a1a1a1a1a1aL);
rotated &= ~c;
rotated >>= 2;
rotated &= uint64_t(0x2020202020202020L);
c += rotated;
}
} // namespace
void toLowerAscii(char* str, size_t length) {
static const size_t kAlignMask64 = 7;
static const size_t kAlignMask32 = 3;
// Convert a character at a time until we reach an address that
// is at least 32-bit aligned
size_t n = (size_t)str;
n &= kAlignMask32;
n = std::min(n, length);
size_t offset = 0;
if (n != 0) {
n = std::min(4 - n, length);
do {
toLowerAscii8(str[offset]);
offset++;
} while (offset < n);
}
n = (size_t)(str + offset);
n &= kAlignMask64;
if ((n != 0) && (offset + 4 <= length)) {
// The next address is 32-bit aligned but not 64-bit aligned.
// Convert the next 4 bytes in order to get to the 64-bit aligned
// part of the input.
toLowerAscii32(*(uint32_t*)(str + offset));
offset += 4;
}
// Convert 8 characters at a time
while (offset + 8 <= length) {
toLowerAscii64(*(uint64_t*)(str + offset));
offset += 8;
}
// Convert 4 characters at a time
while (offset + 4 <= length) {
toLowerAscii32(*(uint32_t*)(str + offset));
offset += 4;
}
// Convert any characters remaining after the last 4-byte aligned group
while (offset < length) {
toLowerAscii8(str[offset]);
offset++;
}
}
namespace detail {
size_t hexDumpLine(const void* ptr, size_t offset, size_t size,
std::string& line) {
static char hexValues[] = "0123456789abcdef";
// Line layout:
// 8: address
// 1: space
// (1+2)*16: hex bytes, each preceded by a space
// 1: space separating the two halves
// 3: " |"
// 16: characters
// 1: "|"
// Total: 78
line.clear();
line.reserve(78);
const uint8_t* p = reinterpret_cast<const uint8_t*>(ptr) + offset;
size_t n = std::min(size - offset, size_t(16));
line.push_back(hexValues[(offset >> 28) & 0xf]);
line.push_back(hexValues[(offset >> 24) & 0xf]);
line.push_back(hexValues[(offset >> 20) & 0xf]);
line.push_back(hexValues[(offset >> 16) & 0xf]);
line.push_back(hexValues[(offset >> 12) & 0xf]);
line.push_back(hexValues[(offset >> 8) & 0xf]);
line.push_back(hexValues[(offset >> 4) & 0xf]);
line.push_back(hexValues[offset & 0xf]);
line.push_back(' ');
for (size_t i = 0; i < n; i++) {
if (i == 8) {
line.push_back(' ');
}
line.push_back(' ');
line.push_back(hexValues[(p[i] >> 4) & 0xf]);
line.push_back(hexValues[p[i] & 0xf]);
}
// 3 spaces for each byte we're not printing, one separating the halves
// if necessary
line.append(3 * (16 - n) + (n <= 8), ' ');
line.append(" |");
for (size_t i = 0; i < n; i++) {
char c = (p[i] >= 32 && p[i] <= 126 ? static_cast<char>(p[i]) : '.');
line.push_back(c);
}
line.append(16 - n, ' ');
line.push_back('|');
DCHECK_EQ(line.size(), 78u);
return n;
}
} // namespace detail
std::string stripLeftMargin(std::string s) {
std::vector<StringPiece> pieces;
split("\n", s, pieces);
auto piecer = range(pieces);
auto piece = (piecer.end() - 1);
auto needle = std::find_if(piece->begin(),
piece->end(),
[](char c) { return c != ' ' && c != '\t'; });
if (needle == piece->end()) {
(piecer.end() - 1)->clear();
}
piece = piecer.begin();
needle = std::find_if(piece->begin(),
piece->end(),
[](char c) { return c != ' ' && c != '\t'; });
if (needle == piece->end()) {
piecer.erase(piecer.begin(), piecer.begin() + 1);
}
const auto sentinel = std::numeric_limits<size_t>::max();
auto indent = sentinel;
size_t max_length = 0;
for (piece = piecer.begin(); piece != piecer.end(); piece++) {
needle = std::find_if(piece->begin(),
piece->end(),
[](char c) { return c != ' ' && c != '\t'; });
if (needle != piece->end()) {
indent = std::min<size_t>(indent, size_t(needle - piece->begin()));
} else {
max_length = std::max<size_t>(piece->size(), max_length);
}
}
indent = indent == sentinel ? max_length : indent;
for (piece = piecer.begin(); piece != piecer.end(); piece++) {
if (piece->size() < indent) {
piece->clear();
} else {
piece->erase(piece->begin(), piece->begin() + indent);
}
}
return join("\n", piecer);
}
} // namespace folly
#ifdef FOLLY_DEFINED_DMGL
# undef FOLLY_DEFINED_DMGL
# undef DMGL_NO_OPTS
# undef DMGL_PARAMS
# undef DMGL_ANSI
# undef DMGL_JAVA
# undef DMGL_VERBOSE
# undef DMGL_TYPES
# undef DMGL_RET_POSTFIX
#endif