grab from latest android

git-svn-id: http://skia.googlecode.com/svn/trunk@27 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 642 insertions, 0 deletions

diff --git a/src/core/SkString.cpp b/src/core/SkString.cpp
new file mode 100644
index 0000000000..2e5d9466a1
--- /dev/null
+++ b/src/core/SkString.cpp
@@ -0,0 +1,642 @@
+/* libs/graphics/sgl/SkString.cpp
+**
+** Copyright 2006, The Android Open Source Project
+**
+** 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 "SkString.h"
+#include "SkFixed.h"
+#include "SkUtils.h"
+#include <stdarg.h>
+
+bool SkStrStartsWith(const char string[], const char prefix[])
+{
+    SkASSERT(string);
+    SkASSERT(prefix);
+    return !strncmp(string, prefix, strlen(prefix));
+}
+
+bool SkStrEndsWith(const char string[], const char suffix[])
+{
+    SkASSERT(string);
+    SkASSERT(suffix);
+    size_t  strLen = strlen(string);
+    size_t  suffixLen = strlen(suffix);
+    return  strLen >= suffixLen &&
+            !strncmp(string + strLen - suffixLen, suffix, suffixLen);
+}
+
+int SkStrStartsWithOneOf(const char string[], const char prefixes[])
+{
+    int index = 0;
+    do {
+        const char* limit = strchr(prefixes, '\0');
+        if (!strncmp(string, prefixes, limit - prefixes))
+            return index;
+        prefixes = limit + 1;
+        index++;
+    } while (prefixes[0]);
+    return -1;
+}
+
+char* SkStrAppendS32(char string[], int32_t dec)
+{
+    SkDEBUGCODE(char* start = string;)
+
+    char    buffer[SkStrAppendS32_MaxSize];
+    char*   p = buffer + sizeof(buffer);
+    bool    neg = false;
+
+    if (dec < 0)
+    {
+        neg = true;
+        dec = -dec;
+    }
+    do {
+        *--p = SkToU8('0' + dec % 10);
+        dec /= 10;
+    } while (dec != 0);
+    if (neg)
+        *--p = '-';
+
+    SkASSERT(p >= buffer);
+    char* stop = buffer + sizeof(buffer);
+    while (p < stop)
+        *string++ = *p++;
+
+    SkASSERT(string - start <= SkStrAppendS32_MaxSize);
+    return string;
+}
+
+char* SkStrAppendScalar(char string[], SkScalar value)
+{
+    SkDEBUGCODE(char* start = string;)
+
+    SkFixed x = SkScalarToFixed(value);
+
+    if (x < 0)
+    {
+        *string++ = '-';
+        x = -x;
+    }
+
+    unsigned frac = x & 0xFFFF;
+    x >>= 16;
+    if (frac == 0xFFFF) // need to do this to "round up", since 65535/65536 is closer to 1 than to .9999
+    {
+        x += 1;
+        frac = 0;
+    }
+    string = SkStrAppendS32(string, x);
+
+    // now handle the fractional part (if any)
+    if (frac)
+    {
+        static const uint16_t   gTens[] = { 1000, 100, 10, 1 };
+        const uint16_t*         tens = gTens;
+
+        x = SkFixedRound(frac * 10000);
+        SkASSERT(x <= 10000);
+        if (x == 10000) {
+            x -= 1;
+        }
+        *string++ = '.';
+        do {
+            unsigned powerOfTen = *tens++;
+            *string++ = SkToU8('0' + x / powerOfTen);
+            x %= powerOfTen;
+        } while (x != 0);
+    }
+    
+    SkASSERT(string - start <= SkStrAppendScalar_MaxSize);
+    return string;
+}
+
+////////////////////////////////////////////////////////////////////////////////////
+
+#define kMaxRefCnt_SkString     SK_MaxU16
+
+// the 3 values are [length] [refcnt] [terminating zero data]
+const SkString::Rec SkString::gEmptyRec = { 0, 0, 0 };
+
+#define SizeOfRec()     (gEmptyRec.data() - (const char*)&gEmptyRec)
+
+SkString::Rec* SkString::AllocRec(const char text[], U16CPU len)
+{
+    Rec* rec;
+
+    if (len == 0)
+        rec = const_cast<Rec*>(&gEmptyRec);
+    else
+    {
+        // add 1 for terminating 0, then align4 so we can have some slop when growing the string
+        rec = (Rec*)sk_malloc_throw(SizeOfRec() + SkAlign4(len + 1));
+        rec->fLength = SkToU16(len);
+        rec->fRefCnt = 1;
+        if (text)
+            memcpy(rec->data(), text, len);
+        rec->data()[len] = 0;
+    }
+    return rec;
+}
+
+SkString::Rec* SkString::RefRec(Rec* src)
+{
+    if (src != &gEmptyRec)
+    {
+        if (src->fRefCnt == kMaxRefCnt_SkString) {
+            src = AllocRec(src->data(), src->fLength);
+        } else
+            src->fRefCnt += 1;
+    }
+    return src;
+}
+
+#ifdef SK_DEBUG
+void SkString::validate() const
+{
+    // make sure know one has written over our global
+    SkASSERT(gEmptyRec.fLength == 0);
+    SkASSERT(gEmptyRec.fRefCnt == 0);
+    SkASSERT(gEmptyRec.data()[0] == 0);
+
+    if (fRec != &gEmptyRec)
+    {
+        SkASSERT(fRec->fLength > 0);
+        SkASSERT(fRec->fRefCnt > 0);
+        SkASSERT(fRec->data()[fRec->fLength] == 0);
+    }
+    SkASSERT(fStr == c_str());
+}
+#endif
+
+///////////////////////////////////////////////////////////////////////
+
+SkString::SkString() : fRec(const_cast<Rec*>(&gEmptyRec)) {
+#ifdef SK_DEBUG
+    fStr = fRec->data();
+#endif
+}
+
+SkString::SkString(size_t len)
+{
+    SkASSERT(SkToU16(len) == len);  // can't handle larger than 64K
+
+    fRec = AllocRec(NULL, (U16CPU)len);
+#ifdef SK_DEBUG
+    fStr = fRec->data();
+#endif
+}
+
+SkString::SkString(const char text[])
+{
+    size_t  len = text ? strlen(text) : 0;
+
+    fRec = AllocRec(text, (U16CPU)len);
+#ifdef SK_DEBUG
+    fStr = fRec->data();
+#endif
+}
+
+SkString::SkString(const char text[], size_t len)
+{
+    fRec = AllocRec(text, (U16CPU)len);
+#ifdef SK_DEBUG
+    fStr = fRec->data();
+#endif
+}
+
+SkString::SkString(const SkString& src)
+{
+    src.validate();
+
+    fRec = RefRec(src.fRec);
+#ifdef SK_DEBUG
+    fStr = fRec->data();
+#endif
+}
+
+SkString::~SkString()
+{
+    this->validate();
+
+    if (fRec->fLength)
+    {
+        SkASSERT(fRec->fRefCnt > 0);
+        if (--fRec->fRefCnt == 0)
+            sk_free(fRec);
+    }
+}
+
+bool SkString::equals(const SkString& src) const
+{
+    return fRec == src.fRec || this->equals(src.c_str(), src.size());
+}
+
+bool SkString::equals(const char text[]) const
+{
+    return this->equals(text, text ? strlen(text) : 0);
+}
+
+bool SkString::equals(const char text[], size_t len) const
+{
+    SkASSERT(len == 0 || text != NULL);
+
+    return fRec->fLength == len && !memcmp(fRec->data(), text, len);
+}
+
+SkString& SkString::operator=(const SkString& src)
+{
+    this->validate();
+
+    if (fRec != src.fRec)
+    {
+        SkString    tmp(src);
+        this->swap(tmp);
+    }
+    return *this;
+}
+
+void SkString::reset()
+{
+    this->validate();
+
+    if (fRec->fLength)
+    {
+        SkASSERT(fRec->fRefCnt > 0);
+        if (--fRec->fRefCnt == 0)
+            sk_free(fRec);
+    }
+
+    fRec = const_cast<Rec*>(&gEmptyRec);
+#ifdef SK_DEBUG
+    fStr = fRec->data();
+#endif
+}
+
+char* SkString::writable_str()
+{
+    this->validate();
+
+    if (fRec->fLength)
+    {
+        if (fRec->fRefCnt > 1)
+        {
+            fRec->fRefCnt -= 1;
+            fRec = AllocRec(fRec->data(), fRec->fLength);
+        #ifdef SK_DEBUG
+            fStr = fRec->data();
+        #endif
+        }
+    }
+    return fRec->data();
+}
+
+void SkString::set(const char text[])
+{
+    this->set(text, text ? strlen(text) : 0);
+}
+
+void SkString::set(const char text[], size_t len)
+{
+    if (len == 0)
+        this->reset();
+    else if (fRec->fRefCnt == 1 && len <= fRec->fLength)    // should we resize if len <<<< fLength, to save RAM? (e.g. len < (fLength>>1))
+    {
+        // just use less of the buffer without allocating a smaller one
+        char* p = this->writable_str();
+        if (text)
+            memcpy(p, text, len);
+        p[len] = 0;
+        fRec->fLength = SkToU16(len);
+    }
+    else if (fRec->fRefCnt == 1 && ((unsigned)fRec->fLength >> 2) == (len >> 2))
+    {
+        // we have spare room in the current allocation, so don't alloc a larger one
+        char* p = this->writable_str();
+        if (text)
+            memcpy(p, text, len);
+        p[len] = 0;
+        fRec->fLength = SkToU16(len);
+    }
+    else
+    {
+        SkString tmp(text, len);
+        this->swap(tmp);
+    }
+}
+
+void SkString::setUTF16(const uint16_t src[])
+{
+    int count = 0;
+
+    while (src[count])
+        count += 1;
+    setUTF16(src, count);
+}
+
+void SkString::setUTF16(const uint16_t src[], size_t count)
+{
+    if (count == 0)
+        this->reset();
+    else if (count <= fRec->fLength)    // should we resize if len <<<< fLength, to save RAM? (e.g. len < (fLength>>1))
+    {
+        if (count < fRec->fLength)
+            this->resize(count);
+        char* p = this->writable_str();
+        for (size_t i = 0; i < count; i++)
+            p[i] = SkToU8(src[i]);
+        p[count] = 0;
+    }
+    else
+    {
+        SkString    tmp(count); // puts a null terminator at the end of the string
+        char*       p = tmp.writable_str();
+
+        for (size_t i = 0; i < count; i++)
+            p[i] = SkToU8(src[i]);
+
+        this->swap(tmp);
+    }
+}
+
+void SkString::insert(size_t offset, const char text[])
+{
+    this->insert(offset, text, text ? strlen(text) : 0);
+}
+
+void SkString::insert(size_t offset, const char text[], size_t len)
+{
+    if (len)
+    {
+        size_t length = fRec->fLength;
+        if (offset > length)
+            offset = length;
+
+        /*  If we're the only owner, and we have room in our allocation for the insert,
+            do it in place, rather than allocating a new buffer.
+
+            To know we have room, compare the allocated sizes
+            beforeAlloc = SkAlign4(length + 1)
+            afterAlloc  = SkAligh4(length + 1 + len)
+            but SkAlign4(x) is (x + 3) >> 2 << 2
+            which is equivalent for testing to (length + 1 + 3) >> 2 == (length + 1 + 3 + len) >> 2
+            and we can then eliminate the +1+3 since that doesn't affec the answer
+        */
+        if (fRec->fRefCnt == 1 && (length >> 2) == ((length + len) >> 2))
+        {
+            char* dst = this->writable_str();
+
+            if (offset < length)
+                memmove(dst + offset + len, dst + offset, length - offset);
+            memcpy(dst + offset, text, len);
+
+            dst[length + len] = 0;
+            fRec->fLength = SkToU16(length + len);
+        }
+        else
+        {
+            /*  Seems we should use realloc here, since that is safe if it fails
+                (we have the original data), and might be faster than alloc/copy/free.
+            */
+            SkString    tmp(fRec->fLength + len);
+            char*       dst = tmp.writable_str();
+
+            if (offset > 0)
+                memcpy(dst, fRec->data(), offset);
+            memcpy(dst + offset, text, len);
+            if (offset < fRec->fLength)
+                memcpy(dst + offset + len, fRec->data() + offset, fRec->fLength - offset);
+
+            this->swap(tmp);
+        }
+    }
+}
+
+void SkString::insertUnichar(size_t offset, SkUnichar uni)
+{
+    char    buffer[kMaxBytesInUTF8Sequence];
+    size_t  len = SkUTF8_FromUnichar(uni, buffer);
+
+    if (len)
+        this->insert(offset, buffer, len);
+}
+
+void SkString::insertS32(size_t offset, int32_t dec)
+{
+    char    buffer[SkStrAppendS32_MaxSize];
+    char*   stop = SkStrAppendS32(buffer, dec);
+    this->insert(offset, buffer, stop - buffer);
+}
+
+void SkString::insertHex(size_t offset, uint32_t hex, int minDigits)
+{
+    minDigits = SkPin32(minDigits, 0, 8);
+    
+    static const char gHex[] = "0123456789ABCDEF";
+
+    char    buffer[8];
+    char*   p = buffer + sizeof(buffer);
+
+    do {
+        *--p = gHex[hex & 0xF];
+        hex >>= 4;
+        minDigits -= 1;
+    } while (hex != 0);
+    while (--minDigits >= 0)
+        *--p = '0';
+
+    SkASSERT(p >= buffer);
+    this->insert(offset, p, buffer + sizeof(buffer) - p);
+}
+
+void SkString::insertScalar(size_t offset, SkScalar value)
+{
+    char    buffer[SkStrAppendScalar_MaxSize];
+    char*   stop = SkStrAppendScalar(buffer, value);
+    this->insert(offset, buffer, stop - buffer);
+}
+
+///////////////////////////////////////////////////////////////////////////
+
+#include <stdio.h>
+
+// number of bytes (on the stack) to receive the printf result
+static const size_t kBufferSize = 256;
+
+#ifdef SK_BUILD_FOR_WIN
+    #define VSNPRINTF   _vsnprintf
+#else
+    #define VSNPRINTF   vsnprintf
+#endif
+
+#define ARGS_TO_BUFFER(format, buffer, size)        \
+    do {                                            \
+        va_list args;                               \
+        va_start(args, format);                     \
+        VSNPRINTF(buffer, size, format, args);      \
+        va_end(args);                               \
+    } while (0)
+
+void SkString::printf(const char format[], ...) {
+    char    buffer[kBufferSize];
+    ARGS_TO_BUFFER(format, buffer, kBufferSize);
+
+    this->set(buffer, strlen(buffer));
+}
+
+void SkString::appendf(const char format[], ...) {
+    char    buffer[kBufferSize];
+    ARGS_TO_BUFFER(format, buffer, kBufferSize);
+    
+    this->append(buffer, strlen(buffer));
+}
+
+void SkString::prependf(const char format[], ...) {
+    char    buffer[kBufferSize];
+    ARGS_TO_BUFFER(format, buffer, kBufferSize);
+    
+    this->prepend(buffer, strlen(buffer));
+}
+
+#undef VSNPRINTF
+
+///////////////////////////////////////////////////////////////////////////
+
+void SkString::remove(size_t offset, size_t length)
+{
+    size_t size = this->size();
+
+    if (offset < size)
+    {
+        if (offset + length > size)
+            length = size - offset;
+        if (length > 0)
+        {
+            SkASSERT(size > length);
+            SkString    tmp(size - length);
+            char*       dst = tmp.writable_str();
+            const char* src = this->c_str();
+
+            if (offset)
+            {
+                SkASSERT(offset <= tmp.size());
+                memcpy(dst, src, offset);
+            }
+            size_t tail = size - offset - length;
+            SkASSERT((int32_t)tail >= 0);
+            if (tail)
+            {
+        //      SkASSERT(offset + length <= tmp.size());
+                memcpy(dst + offset, src + offset + length, tail);
+            }
+            SkASSERT(dst[tmp.size()] == 0);
+            this->swap(tmp);
+        }
+    }
+}
+
+void SkString::swap(SkString& other)
+{
+    this->validate();
+    other.validate();
+
+    SkTSwap<Rec*>(fRec, other.fRec);
+#ifdef SK_DEBUG
+    SkTSwap<const char*>(fStr, other.fStr);
+#endif
+}
+
+/////////////////////////////////////////////////////////////////////////////////
+
+SkAutoUCS2::SkAutoUCS2(const char utf8[])
+{
+    size_t len = strlen(utf8);
+    fUCS2 = (uint16_t*)sk_malloc_throw((len + 1) * sizeof(uint16_t));
+
+    uint16_t* dst = fUCS2;
+    for (;;)
+    {
+        SkUnichar   uni = SkUTF8_NextUnichar(&utf8);
+        *dst++ = SkToU16(uni);
+        if (uni == 0)
+            break;
+    }
+    fCount = (int)(dst - fUCS2);
+}
+
+SkAutoUCS2::~SkAutoUCS2()
+{
+    delete[] fUCS2;
+}
+
+/////////////////////////////////////////////////////////////////////////////////
+/////////////////////////////////////////////////////////////////////////////////
+
+#ifdef SK_DEBUG
+
+void SkString::UnitTest()
+{
+#ifdef SK_SUPPORT_UNITTEST
+    SkString    a;
+    SkString    b((size_t)0);
+    SkString    c("");
+    SkString    d(NULL, 0);
+
+    SkASSERT(a.isEmpty());
+    SkASSERT(a == b && a == c && a == d);
+
+    a.set("hello");
+    b.set("hellox", 5);
+    c.set(a);
+    d.resize(5);
+    memcpy(d.writable_str(), "helloz", 5);
+
+    SkASSERT(!a.isEmpty());
+    SkASSERT(a.size() == 5);
+    SkASSERT(a == b && a == c && a == d);
+    SkASSERT(a.equals("hello", 5));
+    SkASSERT(a.equals("hello"));
+    SkASSERT(!a.equals("help"));
+
+    SkString    e(a);
+    SkString    f("hello");
+    SkString    g("helloz", 5);
+
+    SkASSERT(a == e && a == f && a == g);
+
+    b.set("world");
+    c = b;
+    SkASSERT(a != b && a != c && b == c);
+
+    a.append(" world");
+    e.append("worldz", 5);
+    e.insert(5, " ");
+    f.set("world");
+    f.prepend("hello ");
+    SkASSERT(a.equals("hello world") && a == e && a == f);
+
+    a.reset();
+    b.resize(0);
+    SkASSERT(a.isEmpty() && b.isEmpty() && a == b);
+
+    a.set("a");
+    a.set("ab");
+    a.set("abc");
+    a.set("abcd");
+#endif
+}
+
+#endif
+