gecko-dev/js/js2/utilities.h
2000-02-19 09:26:59 +00:00

408 lines
13 KiB
C++

// -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
//
// The contents of this file are subject to the Netscape Public
// License Version 1.1 (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.mozilla.org/NPL/
//
// Software distributed under the License is distributed on an "AS
// IS" basis, WITHOUT WARRANTY OF ANY KIND, either express oqr
// implied. See the License for the specific language governing
// rights and limitations under the License.
//
// The Original Code is the JavaScript 2 Prototype.
//
// The Initial Developer of the Original Code is Netscape
// Communications Corporation. Portions created by Netscape are
// Copyright (C) 1998 Netscape Communications Corporation. All
// Rights Reserved.
#ifndef utilities_h
#define utilities_h
#include "systemtypes.h"
#include <memory>
#include <string>
#include <iostream>
#ifndef _WIN32 // Microsoft VC6 bug: standard identifiers should be in std namespace
using std::size_t;
using std::ptrdiff_t;
using std::strlen;
using std::strcpy;
#define STD std
#else
#define STD
#endif
using std::string;
using std::istream;
using std::ostream;
using std::auto_ptr;
namespace JavaScript {
//
// Assertions
//
#ifdef DEBUG
void Assert(const char *s, const char *file, int line);
#define ASSERT(_expr) ((_expr) ? (void)0 : JavaScript::Assert(#_expr, __FILE__, __LINE__))
#define NOT_REACHED(_reasonStr) JavaScript::Assert(_reasonStr, __FILE__, __LINE__)
#define DEBUG_ONLY(_stmt) _stmt
#else
#define ASSERT(expr)
#define NOT_REACHED(reasonStr)
#define DEBUG_ONLY(_stmt)
#endif
//
// Numerics
//
template<class N> N min(N v1, N v2) {return v1 <= v2 ? v1 : v2;}
template<class N> N max(N v1, N v2) {return v1 >= v2 ? v1 : v2;}
//
// Bit manipulation
//
#define JS_BIT(n) ((uint32)1 << (n))
#define JS_BITMASK(n) (JS_BIT(n) - 1)
uint ceilingLog2(uint32 n);
uint floorLog2(uint32 n);
//
// Unicode UTF-16 characters and strings
//
// A string of UTF-16 characters. Nulls are allowed just like any other character.
// The string is not null-terminated.
// Use wstring if char16 is wchar_t. Otherwise use basic_string<uint16>.
//
// Eventually we'll want to use a custom class better suited for JavaScript that generates less
// code bloat and separates the concepts of a fixed, read-only string from a mutable buffer that
// is expanding. For now, though, we use the standard basic_string.
typedef std::basic_string<char16> String;
typedef uint32 char16orEOF; // A type that can hold any char16 plus one special value: ueof.
const char16orEOF char16eof = static_cast<char16orEOF>(-1);
// If c is a char16, return it; if c is char16eof, return the character \uFFFF.
inline char16 char16orEOFToChar16(char16orEOF c) {return static_cast<char16>(c);}
// Special char16s
namespace uni {
const char16 null = '\0';
const char16 cr = '\r';
const char16 lf = '\n';
const char16 ls = 0x2028;
const char16 ps = 0x2029;
}
const uint16 firstFormatChar = 0x200C; // Lowest Unicode Cf character
inline char16 widen(char ch) {return static_cast<char16>(static_cast<uchar>(ch));}
#ifndef _WIN32
// Return a String containing the characters of the null-terminated C string cstr
// (without the trailing null).
inline String widenCString(const char *cstr)
{
size_t len = strlen(cstr);
const uchar *ucstr = reinterpret_cast<const uchar *>(cstr);
return String(ucstr, ucstr+len);
}
// Widen and append length characters starting at chars to the end of str.
inline void appendChars(String &str, const char *chars, size_t length)
{
const uchar *uchars = reinterpret_cast<const uchar *>(chars);
str.append(uchars, uchars + length);
}
#else // Microsoft VC6 bug: String constructor and append limited to char16 iterators
String widenCString(const char *cstr);
void appendChars(String &str, const char *chars, size_t length);
#endif
String &operator+=(String &str, const char *cstr);
String operator+(const String &str, const char *cstr);
String operator+(const char *cstr, const String &str);
inline String &operator+=(String &str, char c) {return str += widen(c);}
inline void clear(String &s) {s.resize(0);}
class CharInfo {
uint32 info; // Word from table a.
// Unicode character attribute lookup tables
static const uint8 x[];
static const uint8 y[];
static const uint32 a[];
public:
// Enumerated Unicode general category types
enum Type {
Unassigned = 0, // Cn
UppercaseLetter = 1, // Lu
LowercaseLetter = 2, // Ll
TitlecaseLetter = 3, // Lt
ModifierLetter = 4, // Lm
OtherLetter = 5, // Lo
NonSpacingMark = 6, // Mn
EnclosingMark = 7, // Me
CombiningSpacingMark = 8, // Mc
DecimalDigitNumber = 9, // Nd
LetterNumber = 10, // Nl
OtherNumber = 11, // No
SpaceSeparator = 12, // Zs
LineSeparator = 13, // Zl
ParagraphSeparator = 14, // Zp
Control = 15, // Cc
Format = 16, // Cf
PrivateUse = 18, // Co
Surrogate = 19, // Cs
DashPunctuation = 20, // Pd
StartPunctuation = 21, // Ps
EndPunctuation = 22, // Pe
ConnectorPunctuation = 23, // Pc
OtherPunctuation = 24, // Po
MathSymbol = 25, // Sm
CurrencySymbol = 26, // Sc
ModifierSymbol = 27, // Sk
OtherSymbol = 28 // So
};
enum Group {
NonIdGroup, // 0 May not be part of an identifier
FormatGroup, // 1 Format control
IdGroup, // 2 May start or continue a JS identifier (includes $ and _)
IdContinueGroup, // 3 May continue a JS identifier [(IdContinueGroup & -2) == IdGroup]
WhiteGroup, // 4 White space character (but not line break)
LineBreakGroup // 5 Line break character [(LineBreakGroup & -2) == WhiteGroup]
};
CharInfo() {}
CharInfo(char16 c): info(a[y[x[static_cast<uint16>(c)>>6]<<6 | c&0x3F]]) {}
CharInfo(const CharInfo &ci): info(ci.info) {}
friend Type cType(const CharInfo &ci) {return static_cast<Type>(ci.info & 0x1F);}
friend Group cGroup(const CharInfo &ci) {return static_cast<Group>(ci.info >> 16 & 7);}
friend bool isAlpha(const CharInfo &ci)
{
return ((1<<UppercaseLetter | 1<<LowercaseLetter | 1<<TitlecaseLetter | 1<<ModifierLetter | 1<<OtherLetter)
>> cType(ci) & 1) != 0;
}
friend bool isAlphanumeric(const CharInfo &ci)
{
return ((1<<UppercaseLetter | 1<<LowercaseLetter | 1<<TitlecaseLetter | 1<<ModifierLetter | 1<<OtherLetter |
1<<DecimalDigitNumber | 1<<LetterNumber)
>> cType(ci) & 1) != 0;
}
// Return true if this character can start a JavaScript identifier
friend bool isIdLeading(const CharInfo &ci) {return cGroup(ci) == IdGroup;}
// Return true if this character can continue a JavaScript identifier
friend bool isIdContinuing(const CharInfo &ci) {return (cGroup(ci) & -2) == IdGroup;}
// Return true if this character is a Unicode decimal digit (Nd) character
friend bool isDecimalDigit(const CharInfo &ci) {return cType(ci) == DecimalDigitNumber;}
// Return true if this character is a Unicode white space or line break character
friend bool isSpace(const CharInfo &ci) {return (cGroup(ci) & -2) == WhiteGroup;}
// Return true if this character is a Unicode line break character (LF, CR, LS, or PS)
friend bool isLineBreak(const CharInfo &ci) {return cGroup(ci) == LineBreakGroup;}
// Return true if this character is a Unicode format control character (Cf)
friend bool isFormat(const CharInfo &ci) {return cGroup(ci) == FormatGroup;}
friend bool isUpper(const CharInfo &ci) {return cType(ci) == UppercaseLetter;}
friend bool isLower(const CharInfo &ci) {return cType(ci) == LowercaseLetter;}
friend char16 toUpper(char16 c);
friend char16 toLower(char16 c);
};
inline bool isASCIIDecimalDigit(char16 c) {return c >= '0' && c <= '9';}
bool isASCIIHexDigit(char16 c, uint &digit);
const char16 *skipWhiteSpace(const char16 *str, const char16 *strEnd);
//
// Array auto_ptr's
//
// An ArrayAutoPtr holds a pointer to an array initialized by new T[x].
// A regular auto_ptr cannot be used here because it deletes its pointer using
// delete rather than delete[].
// An appropriate operator[] is also provided.
template <typename T>
class ArrayAutoPtr {
T *ptr;
public:
explicit ArrayAutoPtr(T *p = 0): ptr(p) {}
ArrayAutoPtr(ArrayAutoPtr &a): ptr(a.ptr) {a.ptr = 0;}
ArrayAutoPtr &operator=(ArrayAutoPtr &a) {reset(a.release());}
~ArrayAutoPtr() {delete[] ptr;}
T &operator*() const {return *ptr;}
T &operator->() const {return *ptr;}
template<class N> T &operator[](N i) const {return ptr[i];}
T *get() const {return ptr;}
T *release() {T *p = ptr; ptr = 0; return p;}
void reset(T *p = 0) {delete[] ptr; ptr = p;}
};
typedef ArrayAutoPtr<char> CharAutoPtr;
//
// Growable arrays
//
// private
template <typename T>
class ProtoArrayBuffer {
protected:
T *buffer;
int32 length;
int32 bufferSize;
void append(const T *elts, int32 nElts, T *cache);
};
// private
template <typename T>
void ProtoArrayBuffer<T>::append(const T *elts, int32 nElts, T *cache)
{
assert(nElts >= 0);
int32 newLength = length + nElts;
if (newLength > bufferSize) {
// Allocate a new buffer and copy the current buffer's contents there.
int32 newBufferSize = newLength + bufferSize;
auto_ptr<T> newBuffer = new T[newBufferSize];
T *p = buffer;
T *pLimit = old + length;
T *q = newBuffer.get();
while (p != pLimit)
*q++ = *p++;
if (buffer != cache)
delete buffer;
buffer = newBuffer.release();
bufferSize = newBufferSize;
}
length = newLength;
}
// An ArrayBuffer represents an array of elements of type T. The ArrayBuffer contains
// storage for a fixed size array of cacheSize elements; if this size is exceeded, the
// ArrayBuffer allocates the array from the heap.
// Use append to append nElts elements to the end of the ArrayBuffer.
template <typename T, int32 cacheSize>
class ArrayBuffer: public ProtoArrayBuffer<T> {
T cache[cacheSize];
public:
ArrayBuffer() {buffer = &cache; length = cacheSize; bufferSize = cacheSize;}
~ArrayBuffer() {if (buffer != &cache) delete buffer;}
int32 size() const {return length;}
T *front() const {return buffer;}
void append(const T *elts, int32 nElts) {ProtoArrayBuffer<T>::append(elts, nElts, cache);}
};
//
// Algorithms
//
// Assign zero to every element between first inclusive and last exclusive.
// This is equivalent ot fill(first, last, 0) but may be more efficient.
template<class For>
inline void zero(For first, For last)
{
while (first != last)
*first++ = 0;
}
// Assign zero to n elements starting at first.
// This is equivalent ot fill_n(first, n, 0) but may be more efficient.
template<class For, class Size>
inline void zero_n(For first, Size n)
{
while (n--)
*first++ = 0;
}
//
// C++ I/O
//
// A class to remember the format of an ostream so that a function may modify it internally
// without changing it for the caller.
class SaveFormat {
#ifndef __GNUC__ // The GCC libraries don't support ios_base yet.
ostream &o;
std::ios_base::fmtflags flags;
char fill;
#endif
public:
explicit SaveFormat(ostream &out);
~SaveFormat();
};
void showChar(ostream &out, char16 ch);
template<class In>
void showString(ostream &out, In begin, In end)
{
while (begin != end)
showChar(out, *begin++);
}
void showString(ostream &out, const String &str);
//
// Exceptions
//
// A JavaScript exception (other than out-of-memory, for which we use the standard C++
// exception bad_alloc).
struct Exception {
enum Kind {
SyntaxError
};
Kind kind; // The exception's kind
String message; // The detailed message
String sourceFile; // A description of the source code that caused the error
uint32 lineNum; // One-based source line number; 0 if unknown
uint32 charPos; // Zero-based character offset within the line
String sourceLine; // The text of the source line
Exception(Kind kind, const String &message): kind(kind), message(message), lineNum(0) {}
Exception(Kind kind, const String &message, const String &sourceFile, uint32 lineNum, uint32 charPos, const String sourceLine):
kind(kind), message(message), sourceFile(sourceFile), lineNum(lineNum), charPos(charPos), sourceLine(sourceLine) {}
const char *kindString() const;
String fullMessage() const;
};
}
#endif