JavaScriptCore/runtime/UString.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/runtime/UString.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,629 @@
+/*
+ *  Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
+ *  Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
+ *  Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca)
+ *  Copyright (C) 2009 Google Inc. All rights reserved.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public License
+ *  along with this library; see the file COPYING.LIB.  If not, write to
+ *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ *  Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "config.h"
+#include "UString.h"
+
+#include "JSGlobalObjectFunctions.h"
+#include "Collector.h"
+#include "dtoa.h"
+#include "Identifier.h"
+#include "Operations.h"
+#include <ctype.h>
+#include <limits.h>
+#include <limits>
+#include <stdio.h>
+#include <stdlib.h>
+#include <wtf/ASCIICType.h>
+#include <wtf/Assertions.h>
+#include <wtf/MathExtras.h>
+#include <wtf/StringExtras.h>
+#include <wtf/Vector.h>
+#include <wtf/unicode/UTF8.h>
+
+#if HAVE(STRINGS_H)
+#include <strings.h>
+#endif
+
+using namespace WTF;
+using namespace WTF::Unicode;
+using namespace std;
+
+namespace JSC {
+
+extern const double NaN;
+extern const double Inf;
+
+// The null string is immutable, except for refCount.
+UString* UString::s_nullUString;
+
+COMPILE_ASSERT(sizeof(UString) == sizeof(void*), UString_should_stay_small);
+
+void initializeUString()
+{
+    // UStringImpl::empty() does not construct its static string in a threadsafe fashion,
+    // so ensure it has been initialized from here.
+    UStringImpl::empty();
+
+    UString::s_nullUString = new UString;
+}
+
+UString::UString(const char* c)
+    : m_rep(Rep::create(c))
+{
+}
+
+UString::UString(const char* c, unsigned length)
+    : m_rep(Rep::create(c, length))
+{
+}
+
+UString::UString(const UChar* c, unsigned length)
+    : m_rep(Rep::create(c, length))
+{
+}
+
+UString UString::from(int i)
+{
+    UChar buf[1 + sizeof(i) * 3];
+    UChar* end = buf + sizeof(buf) / sizeof(UChar);
+    UChar* p = end;
+
+    if (i == 0)
+        *--p = '0';
+    else if (i == INT_MIN) {
+        char minBuf[1 + sizeof(i) * 3];
+        snprintf(minBuf, sizeof(minBuf), "%d", INT_MIN);
+        return UString(minBuf);
+    } else {
+        bool negative = false;
+        if (i < 0) {
+            negative = true;
+            i = -i;
+        }
+        while (i) {
+            *--p = static_cast<unsigned short>((i % 10) + '0');
+            i /= 10;
+        }
+        if (negative)
+            *--p = '-';
+    }
+
+    return UString(p, static_cast<unsigned>(end - p));
+}
+
+UString UString::from(long long i)
+{
+    UChar buf[1 + sizeof(i) * 3];
+    UChar* end = buf + sizeof(buf) / sizeof(UChar);
+    UChar* p = end;
+
+    if (i == 0)
+        *--p = '0';
+    else if (i == std::numeric_limits<long long>::min()) {
+        char minBuf[1 + sizeof(i) * 3];
+#if OS(WINDOWS)
+        snprintf(minBuf, sizeof(minBuf), "%I64d", std::numeric_limits<long long>::min());
+#else
+        snprintf(minBuf, sizeof(minBuf), "%lld", std::numeric_limits<long long>::min());
+#endif
+        return UString(minBuf);
+    } else {
+        bool negative = false;
+        if (i < 0) {
+            negative = true;
+            i = -i;
+        }
+        while (i) {
+            *--p = static_cast<unsigned short>((i % 10) + '0');
+            i /= 10;
+        }
+        if (negative)
+            *--p = '-';
+    }
+
+    return UString(p, static_cast<unsigned>(end - p));
+}
+
+UString UString::from(unsigned u)
+{
+    UChar buf[sizeof(u) * 3];
+    UChar* end = buf + sizeof(buf) / sizeof(UChar);
+    UChar* p = end;
+
+    if (u == 0)
+        *--p = '0';
+    else {
+        while (u) {
+            *--p = static_cast<unsigned short>((u % 10) + '0');
+            u /= 10;
+        }
+    }
+
+    return UString(p, static_cast<unsigned>(end - p));
+}
+
+UString UString::from(long l)
+{
+    UChar buf[1 + sizeof(l) * 3];
+    UChar* end = buf + sizeof(buf) / sizeof(UChar);
+    UChar* p = end;
+
+    if (l == 0)
+        *--p = '0';
+    else if (l == LONG_MIN) {
+        char minBuf[1 + sizeof(l) * 3];
+        snprintf(minBuf, sizeof(minBuf), "%ld", LONG_MIN);
+        return UString(minBuf);
+    } else {
+        bool negative = false;
+        if (l < 0) {
+            negative = true;
+            l = -l;
+        }
+        while (l) {
+            *--p = static_cast<unsigned short>((l % 10) + '0');
+            l /= 10;
+        }
+        if (negative)
+            *--p = '-';
+    }
+
+    return UString(p, end - p);
+}
+
+UString UString::from(double d)
+{
+    DtoaBuffer buffer;
+    unsigned length;
+    doubleToStringInJavaScriptFormat(d, buffer, &length);
+    return UString(buffer, length);
+}
+
+char* UString::ascii() const
+{
+    static char* asciiBuffer = 0;
+
+    unsigned length = size();
+    unsigned neededSize = length + 1;
+    delete[] asciiBuffer;
+    asciiBuffer = new char[neededSize];
+
+    const UChar* p = data();
+    char* q = asciiBuffer;
+    const UChar* limit = p + length;
+    while (p != limit) {
+        *q = static_cast<char>(p[0]);
+        ++p;
+        ++q;
+    }
+    *q = '\0';
+
+    return asciiBuffer;
+}
+
+bool UString::is8Bit() const
+{
+    const UChar* u = data();
+    const UChar* limit = u + size();
+    while (u < limit) {
+        if (u[0] > 0xFF)
+            return false;
+        ++u;
+    }
+
+    return true;
+}
+
+UChar UString::operator[](unsigned pos) const
+{
+    if (pos >= size())
+        return '\0';
+    return data()[pos];
+}
+
+static inline bool isInfinity(double number)
+{
+    return number == Inf || number == -Inf;
+}
+
+static bool isInfinity(const UChar* data, const UChar* end)
+{
+    return data + 7 < end
+        && data[0] == 'I'
+        && data[1] == 'n'
+        && data[2] == 'f'
+        && data[3] == 'i'
+        && data[4] == 'n'
+        && data[5] == 'i'
+        && data[6] == 't'
+        && data[7] == 'y';
+}
+
+double UString::toDouble(bool tolerateTrailingJunk, bool tolerateEmptyString) const
+{
+    unsigned size = this->size();
+
+    if (size == 1) {
+        UChar c = data()[0];
+        if (isASCIIDigit(c))
+            return c - '0';
+        if (isStrWhiteSpace(c) && tolerateEmptyString)
+            return 0;
+        return NaN;
+    }
+
+    // FIXME: If tolerateTrailingJunk is true, then we want to tolerate junk 
+    // after the number, even if it contains invalid UTF-16 sequences. So we
+    // shouldn't use the UTF8String function, which returns null when it
+    // encounters invalid UTF-16. Further, we have no need to convert the
+    // non-ASCII characters to UTF-8, so the UTF8String does quite a bit of
+    // unnecessary work.
+
+    // FIXME: The space skipping code below skips only ASCII spaces, but callers
+    // need to skip all StrWhiteSpace. The isStrWhiteSpace function does the
+    // right thing but requires UChar, not char, for its argument.
+
+    const UChar* data = this->data();
+    const UChar* end = data + size;
+
+    // Skip leading white space.
+    for (; data < end; ++data) {
+        if (!isStrWhiteSpace(*data))
+            break;
+    }
+
+    // Empty string.
+    if (data == end)
+        return tolerateEmptyString ? 0.0 : NaN;
+
+    double number;
+
+    if (data[0] == '0' && data + 2 < end && (data[1] | 0x20) == 'x' && isASCIIHexDigit(data[2])) {
+        // Hex number.
+        data += 2;
+        const UChar* firstDigitPosition = data;
+        number = 0;
+        while (true) {
+            number = number * 16 + toASCIIHexValue(*data);
+            ++data;
+            if (data == end)
+                break;
+            if (!isASCIIHexDigit(*data))
+                break;
+        }
+        if (number >= mantissaOverflowLowerBound)
+            number = parseIntOverflow(firstDigitPosition, data - firstDigitPosition, 16);
+    } else {
+        // Decimal number.
+
+        // Put into a null-terminated byte buffer.
+        Vector<char, 32> byteBuffer;
+        for (const UChar* characters = data; characters < end; ++characters) {
+            UChar character = *characters;
+            byteBuffer.append(isASCII(character) ? character : 0);
+        }
+        byteBuffer.append(0);
+
+        char* byteBufferEnd;
+        number = WTF::strtod(byteBuffer.data(), &byteBufferEnd);
+        const UChar* pastNumber = data + (byteBufferEnd - byteBuffer.data());
+
+        if ((number || pastNumber != data) && !isInfinity(number))
+            data = pastNumber;
+        else {
+            // We used strtod() to do the conversion. However, strtod() handles
+            // infinite values slightly differently than JavaScript in that it
+            // converts the string "inf" with any capitalization to infinity,
+            // whereas the ECMA spec requires that it be converted to NaN.
+
+            double signedInfinity = Inf;
+            if (data < end) {
+                if (*data == '+')
+                    data++;
+                else if (*data == '-') {
+                    signedInfinity = -Inf;
+                    data++;
+                }
+            }
+            if (isInfinity(data, end)) {
+                number = signedInfinity;
+                data += 8;
+            } else if (isInfinity(number) && data < end && (*data | 0x20) != 'i')
+                data = pastNumber;
+            else
+                return NaN;
+        }
+    }
+
+    // Look for trailing junk.
+    if (!tolerateTrailingJunk) {
+        // Allow trailing white space.
+        for (; data < end; ++data) {
+            if (!isStrWhiteSpace(*data))
+                break;
+        }
+        if (data != end)
+            return NaN;
+    }
+
+    return number;
+}
+
+double UString::toDouble(bool tolerateTrailingJunk) const
+{
+    return toDouble(tolerateTrailingJunk, true);
+}
+
+double UString::toDouble() const
+{
+    return toDouble(false, true);
+}
+
+uint32_t UString::toUInt32(bool* ok) const
+{
+    double d = toDouble();
+    bool b = true;
+
+    if (d != static_cast<uint32_t>(d)) {
+        b = false;
+        d = 0;
+    }
+
+    if (ok)
+        *ok = b;
+
+    return static_cast<uint32_t>(d);
+}
+
+uint32_t UString::toUInt32(bool* ok, bool tolerateEmptyString) const
+{
+    double d = toDouble(false, tolerateEmptyString);
+    bool b = true;
+
+    if (d != static_cast<uint32_t>(d)) {
+        b = false;
+        d = 0;
+    }
+
+    if (ok)
+        *ok = b;
+
+    return static_cast<uint32_t>(d);
+}
+
+uint32_t UString::toStrictUInt32(bool* ok) const
+{
+    if (ok)
+        *ok = false;
+
+    // Empty string is not OK.
+    unsigned len = m_rep->length();
+    if (len == 0)
+        return 0;
+    const UChar* p = m_rep->characters();
+    unsigned short c = p[0];
+
+    // If the first digit is 0, only 0 itself is OK.
+    if (c == '0') {
+        if (len == 1 && ok)
+            *ok = true;
+        return 0;
+    }
+
+    // Convert to UInt32, checking for overflow.
+    uint32_t i = 0;
+    while (1) {
+        // Process character, turning it into a digit.
+        if (c < '0' || c > '9')
+            return 0;
+        const unsigned d = c - '0';
+
+        // Multiply by 10, checking for overflow out of 32 bits.
+        if (i > 0xFFFFFFFFU / 10)
+            return 0;
+        i *= 10;
+
+        // Add in the digit, checking for overflow out of 32 bits.
+        const unsigned max = 0xFFFFFFFFU - d;
+        if (i > max)
+            return 0;
+        i += d;
+
+        // Handle end of string.
+        if (--len == 0) {
+            if (ok)
+                *ok = true;
+            return i;
+        }
+
+        // Get next character.
+        c = *(++p);
+    }
+}
+
+unsigned UString::find(const UString& f, unsigned pos) const
+{
+    unsigned fsz = f.size();
+
+    if (fsz == 1) {
+        UChar ch = f[0];
+        const UChar* end = data() + size();
+        for (const UChar* c = data() + pos; c < end; c++) {
+            if (*c == ch)
+                return static_cast<unsigned>(c - data());
+        }
+        return NotFound;
+    }
+
+    unsigned sz = size();
+    if (sz < fsz)
+        return NotFound;
+    if (fsz == 0)
+        return pos;
+    const UChar* end = data() + sz - fsz;
+    unsigned fsizeminusone = (fsz - 1) * sizeof(UChar);
+    const UChar* fdata = f.data();
+    unsigned short fchar = fdata[0];
+    ++fdata;
+    for (const UChar* c = data() + pos; c <= end; c++) {
+        if (c[0] == fchar && !memcmp(c + 1, fdata, fsizeminusone))
+            return static_cast<unsigned>(c - data());
+    }
+
+    return NotFound;
+}
+
+unsigned UString::find(UChar ch, unsigned pos) const
+{
+    const UChar* end = data() + size();
+    for (const UChar* c = data() + pos; c < end; c++) {
+        if (*c == ch)
+            return static_cast<unsigned>(c - data());
+    }
+
+    return NotFound;
+}
+
+unsigned UString::rfind(const UString& f, unsigned pos) const
+{
+    unsigned sz = size();
+    unsigned fsz = f.size();
+    if (sz < fsz)
+        return NotFound;
+    if (pos > sz - fsz)
+        pos = sz - fsz;
+    if (fsz == 0)
+        return pos;
+    unsigned fsizeminusone = (fsz - 1) * sizeof(UChar);
+    const UChar* fdata = f.data();
+    for (const UChar* c = data() + pos; c >= data(); c--) {
+        if (*c == *fdata && !memcmp(c + 1, fdata + 1, fsizeminusone))
+            return static_cast<unsigned>(c - data());
+    }
+
+    return NotFound;
+}
+
+unsigned UString::rfind(UChar ch, unsigned pos) const
+{
+    if (isEmpty())
+        return NotFound;
+    if (pos + 1 >= size())
+        pos = size() - 1;
+    for (const UChar* c = data() + pos; c >= data(); c--) {
+        if (*c == ch)
+            return static_cast<unsigned>(c - data());
+    }
+
+    return NotFound;
+}
+
+UString UString::substr(unsigned pos, unsigned len) const
+{
+    unsigned s = size();
+
+    if (pos >= s)
+        pos = s;
+    unsigned limit = s - pos;
+    if (len > limit)
+        len = limit;
+
+    if (pos == 0 && len == s)
+        return *this;
+
+    return UString(Rep::create(m_rep, pos, len));
+}
+
+bool operator==(const UString& s1, const char *s2)
+{
+    if (s2 == 0)
+        return s1.isEmpty();
+
+    const UChar* u = s1.data();
+    const UChar* uend = u + s1.size();
+    while (u != uend && *s2) {
+        if (u[0] != (unsigned char)*s2)
+            return false;
+        s2++;
+        u++;
+    }
+
+    return u == uend && *s2 == 0;
+}
+
+bool operator<(const UString& s1, const UString& s2)
+{
+    const unsigned l1 = s1.size();
+    const unsigned l2 = s2.size();
+    const unsigned lmin = l1 < l2 ? l1 : l2;
+    const UChar* c1 = s1.data();
+    const UChar* c2 = s2.data();
+    unsigned l = 0;
+    while (l < lmin && *c1 == *c2) {
+        c1++;
+        c2++;
+        l++;
+    }
+    if (l < lmin)
+        return (c1[0] < c2[0]);
+
+    return (l1 < l2);
+}
+
+bool operator>(const UString& s1, const UString& s2)
+{
+    const unsigned l1 = s1.size();
+    const unsigned l2 = s2.size();
+    const unsigned lmin = l1 < l2 ? l1 : l2;
+    const UChar* c1 = s1.data();
+    const UChar* c2 = s2.data();
+    unsigned l = 0;
+    while (l < lmin && *c1 == *c2) {
+        c1++;
+        c2++;
+        l++;
+    }
+    if (l < lmin)
+        return (c1[0] > c2[0]);
+
+    return (l1 > l2);
+}
+
+CString UString::UTF8String(bool strict) const
+{
+    // Allocate a buffer big enough to hold all the characters.
+    const unsigned length = size();
+    Vector<char, 1024> buffer(length * 3);
+
+    // Convert to runs of 8-bit characters.
+    char* p = buffer.data();
+    const UChar* d = reinterpret_cast<const UChar*>(&data()[0]);
+    ConversionResult result = convertUTF16ToUTF8(&d, d + length, &p, p + buffer.size(), strict);
+    if (result != conversionOK)
+        return CString();
+
+    return CString(buffer.data(), p - buffer.data());
+}
+
+} // namespace JSC