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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef util_Text_h
#define util_Text_h
#include "mozilla/ArrayUtils.h"
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/Casting.h"
#include "mozilla/Latin1.h"
#include "mozilla/Likely.h"
#include "mozilla/TextUtils.h"
#include "mozilla/Utf8.h"
#include <algorithm>
#include <stddef.h>
#include <stdint.h>
#include <string>
#include <type_traits>
#include <utility>
#include "NamespaceImports.h"
#include "js/Utility.h"
#include "util/Unicode.h"
namespace js {
class FrontendContext;
} // namespace js
class JSLinearString;
template <typename CharT>
static constexpr MOZ_ALWAYS_INLINE size_t js_strlen(const CharT* s) {
return std::char_traits<CharT>::length(s);
}
template <typename CharT>
extern const CharT* js_strchr_limit(const CharT* s, char16_t c,
const CharT* limit);
template <typename CharT>
static MOZ_ALWAYS_INLINE size_t js_strnlen(const CharT* s, size_t maxlen) {
for (size_t i = 0; i < maxlen; ++i) {
if (s[i] == '\0') {
return i;
}
}
return maxlen;
}
namespace js {
class JS_PUBLIC_API GenericPrinter;
template <typename CharT>
constexpr uint8_t AsciiDigitToNumber(CharT c) {
using UnsignedCharT = std::make_unsigned_t<CharT>;
auto uc = static_cast<UnsignedCharT>(c);
return uc - '0';
}
template <typename CharT>
static constexpr bool IsAsciiPrintable(CharT c) {
using UnsignedCharT = std::make_unsigned_t<CharT>;
auto uc = static_cast<UnsignedCharT>(c);
return ' ' <= uc && uc <= '~';
}
template <typename Char1, typename Char2>
inline bool EqualChars(const Char1* s1, const Char2* s2, size_t len) {
// Cast |JS::Latin1Char| to |char| to ensure compilers emit std::memcmp for
// the comparison.
if constexpr (std::is_same_v<Char1, char> &&
std::is_same_v<Char2, JS::Latin1Char>) {
return mozilla::ArrayEqual(s1, reinterpret_cast<const char*>(s2), len);
} else if constexpr (std::is_same_v<Char1, JS::Latin1Char> &&
std::is_same_v<Char2, char>) {
return mozilla::ArrayEqual(reinterpret_cast<const char*>(s1), s2, len);
} else {
return mozilla::ArrayEqual(s1, s2, len);
}
}
// Return less than, equal to, or greater than zero depending on whether
// s1 is less than, equal to, or greater than s2.
template <typename Char1, typename Char2>
inline int32_t CompareChars(const Char1* s1, size_t len1, const Char2* s2,
size_t len2) {
size_t n = std::min(len1, len2);
for (size_t i = 0; i < n; i++) {
if (int32_t cmp = s1[i] - s2[i]) {
return cmp;
}
}
return int32_t(len1 - len2);
}
// Return s advanced past any Unicode white space characters.
template <typename CharT>
static inline const CharT* SkipSpace(const CharT* s, const CharT* end) {
MOZ_ASSERT(s <= end);
while (s < end && unicode::IsSpace(*s)) {
s++;
}
return s;
}
extern UniqueChars DuplicateStringToArena(arena_id_t destArenaId, JSContext* cx,
const char* s);
extern UniqueChars DuplicateStringToArena(arena_id_t destArenaId, JSContext* cx,
const char* s, size_t n);
extern UniqueLatin1Chars DuplicateStringToArena(arena_id_t destArenaId,
JSContext* cx,
const Latin1Char* s, size_t n);
extern UniqueTwoByteChars DuplicateStringToArena(arena_id_t destArenaId,
JSContext* cx,
const char16_t* s);
extern UniqueTwoByteChars DuplicateStringToArena(arena_id_t destArenaId,
JSContext* cx,
const char16_t* s, size_t n);
/*
* These variants do not report OOMs, you must arrange for OOMs to be reported
* yourself.
*/
extern UniqueChars DuplicateStringToArena(arena_id_t destArenaId,
const char* s);
extern UniqueChars DuplicateStringToArena(arena_id_t destArenaId, const char* s,
size_t n);
extern UniqueLatin1Chars DuplicateStringToArena(arena_id_t destArenaId,
const JS::Latin1Char* s,
size_t n);
extern UniqueTwoByteChars DuplicateStringToArena(arena_id_t destArenaId,
const char16_t* s);
extern UniqueTwoByteChars DuplicateStringToArena(arena_id_t destArenaId,
const char16_t* s, size_t n);
extern UniqueChars DuplicateString(JSContext* cx, const char* s);
extern UniqueChars DuplicateString(FrontendContext* fc, const char* s);
extern UniqueChars DuplicateString(JSContext* cx, const char* s, size_t n);
extern UniqueLatin1Chars DuplicateString(JSContext* cx, const JS::Latin1Char* s,
size_t n);
extern UniqueTwoByteChars DuplicateString(JSContext* cx, const char16_t* s);
extern UniqueTwoByteChars DuplicateString(FrontendContext* fc,
const char16_t* s);
extern UniqueTwoByteChars DuplicateString(JSContext* cx, const char16_t* s,
size_t n);
/*
* These variants do not report OOMs, you must arrange for OOMs to be reported
* yourself.
*/
extern UniqueChars DuplicateString(const char* s);
extern UniqueChars DuplicateString(const char* s, size_t n);
extern UniqueLatin1Chars DuplicateString(const JS::Latin1Char* s, size_t n);
extern UniqueTwoByteChars DuplicateString(const char16_t* s);
extern UniqueTwoByteChars DuplicateString(const char16_t* s, size_t n);
/*
* Inflate bytes in ASCII encoding to char16_t code units. Return null on error,
* otherwise return the char16_t buffer that was malloc'ed. A null char is
* appended.
*/
extern char16_t* InflateString(JSContext* cx, const char* bytes, size_t length);
/**
* For a valid UTF-8, Latin-1, or WTF-16 code unit sequence, expose its contents
* as the sequence of WTF-16 |char16_t| code units that would identically
* constitute it.
*/
template <typename CharT>
class InflatedChar16Sequence {
private:
const CharT* units_;
const CharT* limit_;
static_assert(std::is_same_v<CharT, char16_t> ||
std::is_same_v<CharT, JS::Latin1Char>,
"InflatedChar16Sequence only supports UTF-8/Latin-1/WTF-16");
public:
InflatedChar16Sequence(const CharT* units, size_t len)
: units_(units), limit_(units_ + len) {}
bool hasMore() { return units_ < limit_; }
char16_t next() {
MOZ_ASSERT(hasMore());
return static_cast<char16_t>(*units_++);
}
HashNumber computeHash() const {
auto copy = *this;
HashNumber hash = 0;
while (copy.hasMore()) {
hash = mozilla::AddToHash(hash, copy.next());
}
return hash;
}
};
template <>
class InflatedChar16Sequence<mozilla::Utf8Unit> {
private:
const mozilla::Utf8Unit* units_;
const mozilla::Utf8Unit* limit_;
char16_t pendingTrailingSurrogate_ = 0;
public:
InflatedChar16Sequence(const mozilla::Utf8Unit* units, size_t len)
: units_(units), limit_(units + len) {}
bool hasMore() { return pendingTrailingSurrogate_ || units_ < limit_; }
char16_t next() {
MOZ_ASSERT(hasMore());
if (MOZ_UNLIKELY(pendingTrailingSurrogate_)) {
char16_t trail = 0;
std::swap(pendingTrailingSurrogate_, trail);
return trail;
}
mozilla::Utf8Unit unit = *units_++;
if (mozilla::IsAscii(unit)) {
return static_cast<char16_t>(unit.toUint8());
}
mozilla::Maybe<char32_t> cp =
mozilla::DecodeOneUtf8CodePoint(unit, &units_, limit_);
MOZ_ASSERT(cp.isSome(), "input code unit sequence required to be valid");
char32_t v = cp.value();
if (v < unicode::NonBMPMin) {
return mozilla::AssertedCast<char16_t>(v);
}
char16_t lead;
unicode::UTF16Encode(v, &lead, &pendingTrailingSurrogate_);
MOZ_ASSERT(unicode::IsLeadSurrogate(lead));
MOZ_ASSERT(pendingTrailingSurrogate_ != 0,
"pendingTrailingSurrogate_ must be nonzero to be detected and "
"returned next go-around");
MOZ_ASSERT(unicode::IsTrailSurrogate(pendingTrailingSurrogate_));
return lead;
}
HashNumber computeHash() const {
auto copy = *this;
HashNumber hash = 0;
while (copy.hasMore()) {
hash = mozilla::AddToHash(hash, copy.next());
}
return hash;
}
};
/*
* Inflate bytes to JS chars in an existing buffer. 'dst' must be large
* enough for 'srclen' char16_t code units. The buffer is NOT null-terminated.
*/
inline void CopyAndInflateChars(char16_t* dst, const char* src, size_t srclen) {
mozilla::ConvertLatin1toUtf16(mozilla::Span(src, srclen),
mozilla::Span(dst, srclen));
}
inline void CopyAndInflateChars(char16_t* dst, const JS::Latin1Char* src,
size_t srclen) {
mozilla::ConvertLatin1toUtf16(mozilla::AsChars(mozilla::Span(src, srclen)),
mozilla::Span(dst, srclen));
}
/*
* Convert one UCS-4 char and write it into a UTF-8 buffer, which must be at
* least 4 bytes long. Return the number of UTF-8 bytes of data written.
*/
extern uint32_t OneUcs4ToUtf8Char(uint8_t* utf8Buffer, char32_t ucs4Char);
extern size_t PutEscapedStringImpl(char* buffer, size_t size,
GenericPrinter* out, JSLinearString* str,
uint32_t quote);
template <typename CharT>
extern size_t PutEscapedStringImpl(char* buffer, size_t bufferSize,
GenericPrinter* out, const CharT* chars,
size_t length, uint32_t quote);
/*
* Write str into buffer escaping any non-printable or non-ASCII character
* using \escapes for JS string literals.
* Guarantees that a NUL is at the end of the buffer unless size is 0. Returns
* the length of the written output, NOT including the NUL. Thus, a return
* value of size or more means that the output was truncated. If buffer
* is null, just returns the length of the output. If quote is not 0, it must
* be a single or double quote character that will quote the output.
*/
inline size_t PutEscapedString(char* buffer, size_t size, JSLinearString* str,
uint32_t quote) {
size_t n = PutEscapedStringImpl(buffer, size, nullptr, str, quote);
/* PutEscapedStringImpl can only fail with a file. */
MOZ_ASSERT(n != size_t(-1));
return n;
}
template <typename CharT>
inline size_t PutEscapedString(char* buffer, size_t bufferSize,
const CharT* chars, size_t length,
uint32_t quote) {
size_t n =
PutEscapedStringImpl(buffer, bufferSize, nullptr, chars, length, quote);
/* PutEscapedStringImpl can only fail with a file. */
MOZ_ASSERT(n != size_t(-1));
return n;
}
inline bool EscapedStringPrinter(GenericPrinter& out, JSLinearString* str,
uint32_t quote) {
return PutEscapedStringImpl(nullptr, 0, &out, str, quote) != size_t(-1);
}
JSString* EncodeURI(JSContext* cx, const char* chars, size_t length);
// Return true if input string contains a given flag in a comma separated list.
bool ContainsFlag(const char* str, const char* flag);
namespace unicode {
/**
* Compute the number of UTF-16 code units in the valid UTF-8 range
* [begin, end).
*/
extern size_t CountUTF16CodeUnits(const mozilla::Utf8Unit* begin,
const mozilla::Utf8Unit* end);
/**
* Count the number of UTF-16 code units in [begin, end).
*/
inline size_t CountUTF16CodeUnits(const char16_t* begin, const char16_t* end) {
MOZ_ASSERT(begin <= end);
return end - begin;
}
} // namespace unicode
} // namespace js
#endif // util_Text_h