gfx/skia/trunk/src/core/SkString.cpp

Sat, 03 Jan 2015 20:18:00 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Sat, 03 Jan 2015 20:18:00 +0100
branch
TOR_BUG_3246
changeset 7
129ffea94266
permissions
-rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

     2 /*
     3  * Copyright 2006 The Android Open Source Project
     4  *
     5  * Use of this source code is governed by a BSD-style license that can be
     6  * found in the LICENSE file.
     7  */
    10 #include "SkString.h"
    11 #include "SkFixed.h"
    12 #include "SkThread.h"
    13 #include "SkUtils.h"
    14 #include <stdarg.h>
    15 #include <stdio.h>
    17 // number of bytes (on the stack) to receive the printf result
    18 static const size_t kBufferSize = 1024;
    20 #ifdef SK_BUILD_FOR_WIN
    21     #define VSNPRINTF(buffer, size, format, args) \
    22         _vsnprintf_s(buffer, size, _TRUNCATE, format, args)
    23     #define SNPRINTF    _snprintf
    24 #else
    25     #define VSNPRINTF   vsnprintf
    26     #define SNPRINTF    snprintf
    27 #endif
    29 #define ARGS_TO_BUFFER(format, buffer, size)        \
    30     do {                                            \
    31         va_list args;                               \
    32         va_start(args, format);                     \
    33         VSNPRINTF(buffer, size, format, args);      \
    34         va_end(args);                               \
    35     } while (0)
    37 ///////////////////////////////////////////////////////////////////////////////
    39 bool SkStrEndsWith(const char string[], const char suffixStr[]) {
    40     SkASSERT(string);
    41     SkASSERT(suffixStr);
    42     size_t  strLen = strlen(string);
    43     size_t  suffixLen = strlen(suffixStr);
    44     return  strLen >= suffixLen &&
    45             !strncmp(string + strLen - suffixLen, suffixStr, suffixLen);
    46 }
    48 bool SkStrEndsWith(const char string[], const char suffixChar) {
    49     SkASSERT(string);
    50     size_t  strLen = strlen(string);
    51     if (0 == strLen) {
    52         return false;
    53     } else {
    54         return (suffixChar == string[strLen-1]);
    55     }
    56 }
    58 int SkStrStartsWithOneOf(const char string[], const char prefixes[]) {
    59     int index = 0;
    60     do {
    61         const char* limit = strchr(prefixes, '\0');
    62         if (!strncmp(string, prefixes, limit - prefixes)) {
    63             return index;
    64         }
    65         prefixes = limit + 1;
    66         index++;
    67     } while (prefixes[0]);
    68     return -1;
    69 }
    71 char* SkStrAppendU32(char string[], uint32_t dec) {
    72     SkDEBUGCODE(char* start = string;)
    74     char    buffer[SkStrAppendU32_MaxSize];
    75     char*   p = buffer + sizeof(buffer);
    77     do {
    78         *--p = SkToU8('0' + dec % 10);
    79         dec /= 10;
    80     } while (dec != 0);
    82     SkASSERT(p >= buffer);
    83     char* stop = buffer + sizeof(buffer);
    84     while (p < stop) {
    85         *string++ = *p++;
    86     }
    87     SkASSERT(string - start <= SkStrAppendU32_MaxSize);
    88     return string;
    89 }
    91 char* SkStrAppendS32(char string[], int32_t dec) {
    92     if (dec < 0) {
    93         *string++ = '-';
    94         dec = -dec;
    95     }
    96     return SkStrAppendU32(string, static_cast<uint32_t>(dec));
    97 }
    99 char* SkStrAppendU64(char string[], uint64_t dec, int minDigits) {
   100     SkDEBUGCODE(char* start = string;)
   102     char    buffer[SkStrAppendU64_MaxSize];
   103     char*   p = buffer + sizeof(buffer);
   105     do {
   106         *--p = SkToU8('0' + (int32_t) (dec % 10));
   107         dec /= 10;
   108         minDigits--;
   109     } while (dec != 0);
   111     while (minDigits > 0) {
   112         *--p = '0';
   113         minDigits--;
   114     }
   116     SkASSERT(p >= buffer);
   117     size_t cp_len = buffer + sizeof(buffer) - p;
   118     memcpy(string, p, cp_len);
   119     string += cp_len;
   121     SkASSERT(string - start <= SkStrAppendU64_MaxSize);
   122     return string;
   123 }
   125 char* SkStrAppendS64(char string[], int64_t dec, int minDigits) {
   126     if (dec < 0) {
   127         *string++ = '-';
   128         dec = -dec;
   129     }
   130     return SkStrAppendU64(string, static_cast<uint64_t>(dec), minDigits);
   131 }
   133 char* SkStrAppendFloat(char string[], float value) {
   134     // since floats have at most 8 significant digits, we limit our %g to that.
   135     static const char gFormat[] = "%.8g";
   136     // make it 1 larger for the terminating 0
   137     char buffer[SkStrAppendScalar_MaxSize + 1];
   138     int len = SNPRINTF(buffer, sizeof(buffer), gFormat, value);
   139     memcpy(string, buffer, len);
   140     SkASSERT(len <= SkStrAppendScalar_MaxSize);
   141     return string + len;
   142 }
   144 char* SkStrAppendFixed(char string[], SkFixed x) {
   145     SkDEBUGCODE(char* start = string;)
   146     if (x < 0) {
   147         *string++ = '-';
   148         x = -x;
   149     }
   151     unsigned frac = x & 0xFFFF;
   152     x >>= 16;
   153     if (frac == 0xFFFF) {
   154         // need to do this to "round up", since 65535/65536 is closer to 1 than to .9999
   155         x += 1;
   156         frac = 0;
   157     }
   158     string = SkStrAppendS32(string, x);
   160     // now handle the fractional part (if any)
   161     if (frac) {
   162         static const uint16_t   gTens[] = { 1000, 100, 10, 1 };
   163         const uint16_t*         tens = gTens;
   165         x = SkFixedRoundToInt(frac * 10000);
   166         SkASSERT(x <= 10000);
   167         if (x == 10000) {
   168             x -= 1;
   169         }
   170         *string++ = '.';
   171         do {
   172             unsigned powerOfTen = *tens++;
   173             *string++ = SkToU8('0' + x / powerOfTen);
   174             x %= powerOfTen;
   175         } while (x != 0);
   176     }
   178     SkASSERT(string - start <= SkStrAppendScalar_MaxSize);
   179     return string;
   180 }
   182 ///////////////////////////////////////////////////////////////////////////////
   184 // the 3 values are [length] [refcnt] [terminating zero data]
   185 const SkString::Rec SkString::gEmptyRec = { 0, 0, 0 };
   187 #define SizeOfRec()     (gEmptyRec.data() - (const char*)&gEmptyRec)
   189 static uint32_t trim_size_t_to_u32(size_t value) {
   190     if (sizeof(size_t) > sizeof(uint32_t)) {
   191         if (value > SK_MaxU32) {
   192             value = SK_MaxU32;
   193         }
   194     }
   195     return (uint32_t)value;
   196 }
   198 static size_t check_add32(size_t base, size_t extra) {
   199     SkASSERT(base <= SK_MaxU32);
   200     if (sizeof(size_t) > sizeof(uint32_t)) {
   201         if (base + extra > SK_MaxU32) {
   202             extra = SK_MaxU32 - base;
   203         }
   204     }
   205     return extra;
   206 }
   208 SkString::Rec* SkString::AllocRec(const char text[], size_t len) {
   209     Rec* rec;
   211     if (0 == len) {
   212         rec = const_cast<Rec*>(&gEmptyRec);
   213     } else {
   214         len = trim_size_t_to_u32(len);
   216         // add 1 for terminating 0, then align4 so we can have some slop when growing the string
   217         rec = (Rec*)sk_malloc_throw(SizeOfRec() + SkAlign4(len + 1));
   218         rec->fLength = SkToU32(len);
   219         rec->fRefCnt = 1;
   220         if (text) {
   221             memcpy(rec->data(), text, len);
   222         }
   223         rec->data()[len] = 0;
   224     }
   225     return rec;
   226 }
   228 SkString::Rec* SkString::RefRec(Rec* src) {
   229     if (src != &gEmptyRec) {
   230         sk_atomic_inc(&src->fRefCnt);
   231     }
   232     return src;
   233 }
   235 #ifdef SK_DEBUG
   236 void SkString::validate() const {
   237     // make sure know one has written over our global
   238     SkASSERT(0 == gEmptyRec.fLength);
   239     SkASSERT(0 == gEmptyRec.fRefCnt);
   240     SkASSERT(0 == gEmptyRec.data()[0]);
   242     if (fRec != &gEmptyRec) {
   243         SkASSERT(fRec->fLength > 0);
   244         SkASSERT(fRec->fRefCnt > 0);
   245         SkASSERT(0 == fRec->data()[fRec->fLength]);
   246     }
   247     SkASSERT(fStr == c_str());
   248 }
   249 #endif
   251 ///////////////////////////////////////////////////////////////////////////////
   253 SkString::SkString() : fRec(const_cast<Rec*>(&gEmptyRec)) {
   254 #ifdef SK_DEBUG
   255     fStr = fRec->data();
   256 #endif
   257 }
   259 SkString::SkString(size_t len) {
   260     fRec = AllocRec(NULL, len);
   261 #ifdef SK_DEBUG
   262     fStr = fRec->data();
   263 #endif
   264 }
   266 SkString::SkString(const char text[]) {
   267     size_t  len = text ? strlen(text) : 0;
   269     fRec = AllocRec(text, len);
   270 #ifdef SK_DEBUG
   271     fStr = fRec->data();
   272 #endif
   273 }
   275 SkString::SkString(const char text[], size_t len) {
   276     fRec = AllocRec(text, len);
   277 #ifdef SK_DEBUG
   278     fStr = fRec->data();
   279 #endif
   280 }
   282 SkString::SkString(const SkString& src) {
   283     src.validate();
   285     fRec = RefRec(src.fRec);
   286 #ifdef SK_DEBUG
   287     fStr = fRec->data();
   288 #endif
   289 }
   291 SkString::~SkString() {
   292     this->validate();
   294     if (fRec->fLength) {
   295         SkASSERT(fRec->fRefCnt > 0);
   296         if (sk_atomic_dec(&fRec->fRefCnt) == 1) {
   297             sk_free(fRec);
   298         }
   299     }
   300 }
   302 bool SkString::equals(const SkString& src) const {
   303     return fRec == src.fRec || this->equals(src.c_str(), src.size());
   304 }
   306 bool SkString::equals(const char text[]) const {
   307     return this->equals(text, text ? strlen(text) : 0);
   308 }
   310 bool SkString::equals(const char text[], size_t len) const {
   311     SkASSERT(len == 0 || text != NULL);
   313     return fRec->fLength == len && !memcmp(fRec->data(), text, len);
   314 }
   316 SkString& SkString::operator=(const SkString& src) {
   317     this->validate();
   319     if (fRec != src.fRec) {
   320         SkString    tmp(src);
   321         this->swap(tmp);
   322     }
   323     return *this;
   324 }
   326 SkString& SkString::operator=(const char text[]) {
   327     this->validate();
   329     SkString tmp(text);
   330     this->swap(tmp);
   332     return *this;
   333 }
   335 void SkString::reset() {
   336     this->validate();
   338     if (fRec->fLength) {
   339         SkASSERT(fRec->fRefCnt > 0);
   340         if (sk_atomic_dec(&fRec->fRefCnt) == 1) {
   341             sk_free(fRec);
   342         }
   343     }
   345     fRec = const_cast<Rec*>(&gEmptyRec);
   346 #ifdef SK_DEBUG
   347     fStr = fRec->data();
   348 #endif
   349 }
   351 char* SkString::writable_str() {
   352     this->validate();
   354     if (fRec->fLength) {
   355         if (fRec->fRefCnt > 1) {
   356             Rec* rec = AllocRec(fRec->data(), fRec->fLength);
   357             if (sk_atomic_dec(&fRec->fRefCnt) == 1) {
   358                 // In this case after our check of fRecCnt > 1, we suddenly
   359                 // did become the only owner, so now we have two copies of the
   360                 // data (fRec and rec), so we need to delete one of them.
   361                 sk_free(fRec);
   362             }
   363             fRec = rec;
   364         #ifdef SK_DEBUG
   365             fStr = fRec->data();
   366         #endif
   367         }
   368     }
   369     return fRec->data();
   370 }
   372 void SkString::set(const char text[]) {
   373     this->set(text, text ? strlen(text) : 0);
   374 }
   376 void SkString::set(const char text[], size_t len) {
   377     len = trim_size_t_to_u32(len);
   379     if (0 == len) {
   380         this->reset();
   381     } else if (1 == fRec->fRefCnt && len <= fRec->fLength) {
   382         // should we resize if len <<<< fLength, to save RAM? (e.g. len < (fLength>>1))?
   383         // just use less of the buffer without allocating a smaller one
   384         char* p = this->writable_str();
   385         if (text) {
   386             memcpy(p, text, len);
   387         }
   388         p[len] = 0;
   389         fRec->fLength = SkToU32(len);
   390     } else if (1 == fRec->fRefCnt && (fRec->fLength >> 2) == (len >> 2)) {
   391         // we have spare room in the current allocation, so don't alloc a larger one
   392         char* p = this->writable_str();
   393         if (text) {
   394             memcpy(p, text, len);
   395         }
   396         p[len] = 0;
   397         fRec->fLength = SkToU32(len);
   398     } else {
   399         SkString tmp(text, len);
   400         this->swap(tmp);
   401     }
   402 }
   404 void SkString::setUTF16(const uint16_t src[]) {
   405     int count = 0;
   407     while (src[count]) {
   408         count += 1;
   409     }
   410     this->setUTF16(src, count);
   411 }
   413 void SkString::setUTF16(const uint16_t src[], size_t count) {
   414     count = trim_size_t_to_u32(count);
   416     if (0 == count) {
   417         this->reset();
   418     } else if (count <= fRec->fLength) {
   419         // should we resize if len <<<< fLength, to save RAM? (e.g. len < (fLength>>1))
   420         if (count < fRec->fLength) {
   421             this->resize(count);
   422         }
   423         char* p = this->writable_str();
   424         for (size_t i = 0; i < count; i++) {
   425             p[i] = SkToU8(src[i]);
   426         }
   427         p[count] = 0;
   428     } else {
   429         SkString tmp(count); // puts a null terminator at the end of the string
   430         char*    p = tmp.writable_str();
   432         for (size_t i = 0; i < count; i++) {
   433             p[i] = SkToU8(src[i]);
   434         }
   435         this->swap(tmp);
   436     }
   437 }
   439 void SkString::insert(size_t offset, const char text[]) {
   440     this->insert(offset, text, text ? strlen(text) : 0);
   441 }
   443 void SkString::insert(size_t offset, const char text[], size_t len) {
   444     if (len) {
   445         size_t length = fRec->fLength;
   446         if (offset > length) {
   447             offset = length;
   448         }
   450         // Check if length + len exceeds 32bits, we trim len
   451         len = check_add32(length, len);
   452         if (0 == len) {
   453             return;
   454         }
   456         /*  If we're the only owner, and we have room in our allocation for the insert,
   457             do it in place, rather than allocating a new buffer.
   459             To know we have room, compare the allocated sizes
   460             beforeAlloc = SkAlign4(length + 1)
   461             afterAlloc  = SkAligh4(length + 1 + len)
   462             but SkAlign4(x) is (x + 3) >> 2 << 2
   463             which is equivalent for testing to (length + 1 + 3) >> 2 == (length + 1 + 3 + len) >> 2
   464             and we can then eliminate the +1+3 since that doesn't affec the answer
   465         */
   466         if (1 == fRec->fRefCnt && (length >> 2) == ((length + len) >> 2)) {
   467             char* dst = this->writable_str();
   469             if (offset < length) {
   470                 memmove(dst + offset + len, dst + offset, length - offset);
   471             }
   472             memcpy(dst + offset, text, len);
   474             dst[length + len] = 0;
   475             fRec->fLength = SkToU32(length + len);
   476         } else {
   477             /*  Seems we should use realloc here, since that is safe if it fails
   478                 (we have the original data), and might be faster than alloc/copy/free.
   479             */
   480             SkString    tmp(fRec->fLength + len);
   481             char*       dst = tmp.writable_str();
   483             if (offset > 0) {
   484                 memcpy(dst, fRec->data(), offset);
   485             }
   486             memcpy(dst + offset, text, len);
   487             if (offset < fRec->fLength) {
   488                 memcpy(dst + offset + len, fRec->data() + offset,
   489                        fRec->fLength - offset);
   490             }
   492             this->swap(tmp);
   493         }
   494     }
   495 }
   497 void SkString::insertUnichar(size_t offset, SkUnichar uni) {
   498     char    buffer[kMaxBytesInUTF8Sequence];
   499     size_t  len = SkUTF8_FromUnichar(uni, buffer);
   501     if (len) {
   502         this->insert(offset, buffer, len);
   503     }
   504 }
   506 void SkString::insertS32(size_t offset, int32_t dec) {
   507     char    buffer[SkStrAppendS32_MaxSize];
   508     char*   stop = SkStrAppendS32(buffer, dec);
   509     this->insert(offset, buffer, stop - buffer);
   510 }
   512 void SkString::insertS64(size_t offset, int64_t dec, int minDigits) {
   513     char    buffer[SkStrAppendS64_MaxSize];
   514     char*   stop = SkStrAppendS64(buffer, dec, minDigits);
   515     this->insert(offset, buffer, stop - buffer);
   516 }
   518 void SkString::insertU32(size_t offset, uint32_t dec) {
   519     char    buffer[SkStrAppendU32_MaxSize];
   520     char*   stop = SkStrAppendU32(buffer, dec);
   521     this->insert(offset, buffer, stop - buffer);
   522 }
   524 void SkString::insertU64(size_t offset, uint64_t dec, int minDigits) {
   525     char    buffer[SkStrAppendU64_MaxSize];
   526     char*   stop = SkStrAppendU64(buffer, dec, minDigits);
   527     this->insert(offset, buffer, stop - buffer);
   528 }
   530 void SkString::insertHex(size_t offset, uint32_t hex, int minDigits) {
   531     minDigits = SkPin32(minDigits, 0, 8);
   533     static const char gHex[] = "0123456789ABCDEF";
   535     char    buffer[8];
   536     char*   p = buffer + sizeof(buffer);
   538     do {
   539         *--p = gHex[hex & 0xF];
   540         hex >>= 4;
   541         minDigits -= 1;
   542     } while (hex != 0);
   544     while (--minDigits >= 0) {
   545         *--p = '0';
   546     }
   548     SkASSERT(p >= buffer);
   549     this->insert(offset, p, buffer + sizeof(buffer) - p);
   550 }
   552 void SkString::insertScalar(size_t offset, SkScalar value) {
   553     char    buffer[SkStrAppendScalar_MaxSize];
   554     char*   stop = SkStrAppendScalar(buffer, value);
   555     this->insert(offset, buffer, stop - buffer);
   556 }
   558 void SkString::printf(const char format[], ...) {
   559     char    buffer[kBufferSize];
   560     ARGS_TO_BUFFER(format, buffer, kBufferSize);
   562     this->set(buffer, strlen(buffer));
   563 }
   565 void SkString::appendf(const char format[], ...) {
   566     char    buffer[kBufferSize];
   567     ARGS_TO_BUFFER(format, buffer, kBufferSize);
   569     this->append(buffer, strlen(buffer));
   570 }
   572 void SkString::appendVAList(const char format[], va_list args) {
   573     char    buffer[kBufferSize];
   574     VSNPRINTF(buffer, kBufferSize, format, args);
   576     this->append(buffer, strlen(buffer));
   577 }
   579 void SkString::prependf(const char format[], ...) {
   580     char    buffer[kBufferSize];
   581     ARGS_TO_BUFFER(format, buffer, kBufferSize);
   583     this->prepend(buffer, strlen(buffer));
   584 }
   586 ///////////////////////////////////////////////////////////////////////////////
   588 void SkString::remove(size_t offset, size_t length) {
   589     size_t size = this->size();
   591     if (offset < size) {
   592         if (offset + length > size) {
   593             length = size - offset;
   594         }
   595         if (length > 0) {
   596             SkASSERT(size > length);
   597             SkString    tmp(size - length);
   598             char*       dst = tmp.writable_str();
   599             const char* src = this->c_str();
   601             if (offset) {
   602                 SkASSERT(offset <= tmp.size());
   603                 memcpy(dst, src, offset);
   604             }
   605             size_t tail = size - offset - length;
   606             SkASSERT((int32_t)tail >= 0);
   607             if (tail) {
   608         //      SkASSERT(offset + length <= tmp.size());
   609                 memcpy(dst + offset, src + offset + length, tail);
   610             }
   611             SkASSERT(dst[tmp.size()] == 0);
   612             this->swap(tmp);
   613         }
   614     }
   615 }
   617 void SkString::swap(SkString& other) {
   618     this->validate();
   619     other.validate();
   621     SkTSwap<Rec*>(fRec, other.fRec);
   622 #ifdef SK_DEBUG
   623     SkTSwap<const char*>(fStr, other.fStr);
   624 #endif
   625 }
   627 ///////////////////////////////////////////////////////////////////////////////
   629 SkString SkStringPrintf(const char* format, ...) {
   630     SkString formattedOutput;
   631     char buffer[kBufferSize];
   632     ARGS_TO_BUFFER(format, buffer, kBufferSize);
   633     formattedOutput.set(buffer);
   634     return formattedOutput;
   635 }
   637 void SkStrSplit(const char* str, const char* delimiters, SkTArray<SkString>* out) {
   638     const char* end = str + strlen(str);
   639     while (str != end) {
   640         // Find a token.
   641         const size_t len = strcspn(str, delimiters);
   642         out->push_back().set(str, len);
   643         str += len;
   644         // Skip any delimiters.
   645         str += strspn(str, delimiters);
   646     }
   647 }
   649 #undef VSNPRINTF
   650 #undef SNPRINTF

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