/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkAtomics.h"
#include "SkString.h"
#include "SkUtils.h"
#include <stdarg.h>
#include <stdio.h>
// number of bytes (on the stack) to receive the printf result
static const size_t kBufferSize = 1024;
#ifdef SK_BUILD_FOR_WIN
#define VSNPRINTF(buffer, size, format, args) \
_vsnprintf_s(buffer, size, _TRUNCATE, format, args)
#define SNPRINTF _snprintf
#else
#define VSNPRINTF vsnprintf
#define SNPRINTF snprintf
#endif
#define ARGS_TO_BUFFER(format, buffer, size, written) \
do { \
va_list args; \
va_start(args, format); \
written = VSNPRINTF(buffer, size, format, args); \
SkASSERT(written >= 0 && written < SkToInt(size)); \
va_end(args); \
} while (0)
#ifdef SK_BUILD_FOR_WIN
#define V_SKSTRING_PRINTF(output, format) \
do { \
va_list args; \
va_start(args, format); \
char buffer[kBufferSize]; \
int length = _vsnprintf_s(buffer, sizeof(buffer), \
_TRUNCATE, format, args); \
va_end(args); \
if (length >= 0 && length < (int)sizeof(buffer)) { \
output.set(buffer, length); \
break; \
} \
va_start(args, format); \
length = _vscprintf(format, args); \
va_end(args); \
SkAutoTMalloc<char> autoTMalloc((size_t)length + 1); \
va_start(args, format); \
SkDEBUGCODE(int check = ) _vsnprintf_s(autoTMalloc.get(), \
length + 1, _TRUNCATE, \
format, args); \
va_end(args); \
SkASSERT(check == length); \
output.set(autoTMalloc.get(), length); \
SkASSERT(output[length] == '\0'); \
} while (false)
#else
#define V_SKSTRING_PRINTF(output, format) \
do { \
va_list args; \
va_start(args, format); \
char buffer[kBufferSize]; \
int length = vsnprintf(buffer, sizeof(buffer), format, args); \
va_end(args); \
if (length < 0) { \
break; \
} \
if (length < (int)sizeof(buffer)) { \
output.set(buffer, length); \
break; \
} \
SkAutoTMalloc<char> autoTMalloc((size_t)length + 1); \
va_start(args, format); \
SkDEBUGCODE(int check = ) vsnprintf(autoTMalloc.get(), \
length + 1, format, args); \
va_end(args); \
SkASSERT(check == length); \
output.set(autoTMalloc.get(), length); \
SkASSERT(output[length] == '\0'); \
} while (false)
#endif
///////////////////////////////////////////////////////////////////////////////
bool SkStrEndsWith(const char string[], const char suffixStr[]) {
SkASSERT(string);
SkASSERT(suffixStr);
size_t strLen = strlen(string);
size_t suffixLen = strlen(suffixStr);
return strLen >= suffixLen &&
!strncmp(string + strLen - suffixLen, suffixStr, suffixLen);
}
bool SkStrEndsWith(const char string[], const char suffixChar) {
SkASSERT(string);
size_t strLen = strlen(string);
if (0 == strLen) {
return false;
} else {
return (suffixChar == string[strLen-1]);
}
}
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* SkStrAppendU32(char string[], uint32_t dec) {
SkDEBUGCODE(char* start = string;)
char buffer[SkStrAppendU32_MaxSize];
char* p = buffer + sizeof(buffer);
do {
*--p = SkToU8('0' + dec % 10);
dec /= 10;
} while (dec != 0);
SkASSERT(p >= buffer);
char* stop = buffer + sizeof(buffer);
while (p < stop) {
*string++ = *p++;
}
SkASSERT(string - start <= SkStrAppendU32_MaxSize);
return string;
}
char* SkStrAppendS32(char string[], int32_t dec) {
uint32_t udec = dec;
if (dec < 0) {
*string++ = '-';
udec = ~udec + 1; // udec = -udec, but silences some warnings that are trying to be helpful
}
return SkStrAppendU32(string, udec);
}
char* SkStrAppendU64(char string[], uint64_t dec, int minDigits) {
SkDEBUGCODE(char* start = string;)
char buffer[SkStrAppendU64_MaxSize];
char* p = buffer + sizeof(buffer);
do {
*--p = SkToU8('0' + (int32_t) (dec % 10));
dec /= 10;
minDigits--;
} while (dec != 0);
while (minDigits > 0) {
*--p = '0';
minDigits--;
}
SkASSERT(p >= buffer);
size_t cp_len = buffer + sizeof(buffer) - p;
memcpy(string, p, cp_len);
string += cp_len;
SkASSERT(string - start <= SkStrAppendU64_MaxSize);
return string;
}
char* SkStrAppendS64(char string[], int64_t dec, int minDigits) {
uint64_t udec = dec;
if (dec < 0) {
*string++ = '-';
udec = ~udec + 1; // udec = -udec, but silences some warnings that are trying to be helpful
}
return SkStrAppendU64(string, udec, minDigits);
}
char* SkStrAppendFloat(char string[], float value) {
// since floats have at most 8 significant digits, we limit our %g to that.
static const char gFormat[] = "%.8g";
// make it 1 larger for the terminating 0
char buffer[SkStrAppendScalar_MaxSize + 1];
int len = SNPRINTF(buffer, sizeof(buffer), gFormat, value);
memcpy(string, buffer, len);
SkASSERT(len <= SkStrAppendScalar_MaxSize);
return string + len;
}
///////////////////////////////////////////////////////////////////////////////
const SkString::Rec SkString::gEmptyRec(0, 0);
#define SizeOfRec() (gEmptyRec.data() - (const char*)&gEmptyRec)
static uint32_t trim_size_t_to_u32(size_t value) {
if (sizeof(size_t) > sizeof(uint32_t)) {
if (value > SK_MaxU32) {
value = SK_MaxU32;
}
}
return (uint32_t)value;
}
static size_t check_add32(size_t base, size_t extra) {
SkASSERT(base <= SK_MaxU32);
if (sizeof(size_t) > sizeof(uint32_t)) {
if (base + extra > SK_MaxU32) {
extra = SK_MaxU32 - base;
}
}
return extra;
}
sk_sp<SkString::Rec> SkString::Rec::Make(const char text[], size_t len) {
if (0 == len) {
return sk_sp<SkString::Rec>(const_cast<Rec*>(&gEmptyRec));
}
len = trim_size_t_to_u32(len);
// add 1 for terminating 0, then align4 so we can have some slop when growing the string
const size_t actualLength = SizeOfRec() + SkAlign4(len + 1);
SkASSERT_RELEASE(len < actualLength); // Check for overflow.
void* storage = ::operator new (actualLength);
sk_sp<Rec> rec(new (storage) Rec(SkToU32(len), 1));
if (text) {
memcpy(rec->data(), text, len);
}
rec->data()[len] = 0;
return rec;
}
void SkString::Rec::ref() const {
if (this == &SkString::gEmptyRec) {
return;
}
SkAssertResult(this->fRefCnt.fetch_add(+1, std::memory_order_relaxed));
}
void SkString::Rec::unref() const {
if (this == &SkString::gEmptyRec) {
return;
}
int32_t oldRefCnt = this->fRefCnt.fetch_add(-1, std::memory_order_acq_rel);
SkASSERT(oldRefCnt);
if (1 == oldRefCnt) {
delete this;
}
}
bool SkString::Rec::unique() const {
return fRefCnt.load(std::memory_order_acquire) == 1;
}
#ifdef SK_DEBUG
void SkString::validate() const {
// make sure know one has written over our global
SkASSERT(0 == gEmptyRec.fLength);
SkASSERT(0 == gEmptyRec.fRefCnt.load(std::memory_order_relaxed));
SkASSERT(0 == gEmptyRec.data()[0]);
if (fRec.get() != &gEmptyRec) {
SkASSERT(fRec->fLength > 0);
SkASSERT(fRec->fRefCnt.load(std::memory_order_relaxed) > 0);
SkASSERT(0 == fRec->data()[fRec->fLength]);
}
}
#endif
///////////////////////////////////////////////////////////////////////////////
SkString::SkString() : fRec(const_cast<Rec*>(&gEmptyRec)) {
}
SkString::SkString(size_t len) {
fRec = Rec::Make(nullptr, len);
}
SkString::SkString(const char text[]) {
size_t len = text ? strlen(text) : 0;
fRec = Rec::Make(text, len);
}
SkString::SkString(const char text[], size_t len) {
fRec = Rec::Make(text, len);
}
SkString::SkString(const SkString& src) {
src.validate();
fRec = src.fRec;
}
SkString::SkString(SkString&& src) {
src.validate();
fRec = std::move(src.fRec);
src.fRec.reset(const_cast<Rec*>(&gEmptyRec));
}
SkString::~SkString() {
this->validate();
}
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 != nullptr);
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;
}
SkString& SkString::operator=(SkString&& src) {
this->validate();
if (fRec != src.fRec) {
this->swap(src);
}
return *this;
}
SkString& SkString::operator=(const char text[]) {
this->validate();
SkString tmp(text);
this->swap(tmp);
return *this;
}
void SkString::reset() {
this->validate();
fRec.reset(const_cast<Rec*>(&gEmptyRec));
}
char* SkString::writable_str() {
this->validate();
if (fRec->fLength) {
if (!fRec->unique()) {
fRec = Rec::Make(fRec->data(), fRec->fLength);
}
}
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) {
len = trim_size_t_to_u32(len);
bool unique = fRec->unique();
if (0 == len) {
this->reset();
} else if (unique && 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 = SkToU32(len);
} else if (unique && (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 = SkToU32(len);
} else {
SkString tmp(text, len);
this->swap(tmp);
}
}
void SkString::setUTF16(const uint16_t src[]) {
int count = 0;
while (src[count]) {
count += 1;
}
this->setUTF16(src, count);
}
void SkString::setUTF16(const uint16_t src[], size_t count) {
count = trim_size_t_to_u32(count);
if (0 == count) {
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;
}
// Check if length + len exceeds 32bits, we trim len
len = check_add32(length, len);
if (0 == len) {
return;
}
/* 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->unique() && (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 = SkToU32(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::insertS64(size_t offset, int64_t dec, int minDigits) {
char buffer[SkStrAppendS64_MaxSize];
char* stop = SkStrAppendS64(buffer, dec, minDigits);
this->insert(offset, buffer, stop - buffer);
}
void SkString::insertU32(size_t offset, uint32_t dec) {
char buffer[SkStrAppendU32_MaxSize];
char* stop = SkStrAppendU32(buffer, dec);
this->insert(offset, buffer, stop - buffer);
}
void SkString::insertU64(size_t offset, uint64_t dec, int minDigits) {
char buffer[SkStrAppendU64_MaxSize];
char* stop = SkStrAppendU64(buffer, dec, minDigits);
this->insert(offset, buffer, stop - buffer);
}
void SkString::insertHex(size_t offset, uint32_t hex, int minDigits) {
minDigits = SkTPin(minDigits, 0, 8);
char buffer[8];
char* p = buffer + sizeof(buffer);
do {
*--p = SkHexadecimalDigits::gUpper[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);
}
void SkString::printf(const char format[], ...) {
V_SKSTRING_PRINTF((*this), format);
}
void SkString::appendf(const char format[], ...) {
char buffer[kBufferSize];
int length;
ARGS_TO_BUFFER(format, buffer, kBufferSize, length);
this->append(buffer, length);
}
void SkString::appendVAList(const char format[], va_list args) {
char buffer[kBufferSize];
int length = VSNPRINTF(buffer, kBufferSize, format, args);
SkASSERT(length >= 0 && length < SkToInt(kBufferSize));
this->append(buffer, length);
}
void SkString::prependf(const char format[], ...) {
char buffer[kBufferSize];
int length;
ARGS_TO_BUFFER(format, buffer, kBufferSize, length);
this->prepend(buffer, length);
}
void SkString::prependVAList(const char format[], va_list args) {
char buffer[kBufferSize];
int length = VSNPRINTF(buffer, kBufferSize, format, args);
SkASSERT(length >= 0 && length < SkToInt(kBufferSize));
this->prepend(buffer, length);
}
///////////////////////////////////////////////////////////////////////////////
void SkString::remove(size_t offset, size_t length) {
size_t size = this->size();
if (offset < size) {
if (length > size - offset) {
length = size - offset;
}
SkASSERT(length <= size);
SkASSERT(offset <= size - length);
if (length > 0) {
SkString tmp(size - length);
char* dst = tmp.writable_str();
const char* src = this->c_str();
if (offset) {
memcpy(dst, src, offset);
}
size_t tail = size - (offset + length);
if (tail) {
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(fRec, other.fRec);
}
///////////////////////////////////////////////////////////////////////////////
SkString SkStringPrintf(const char* format, ...) {
SkString formattedOutput;
V_SKSTRING_PRINTF(formattedOutput, format);
return formattedOutput;
}
void SkStrSplit(const char* str, const char* delimiters, SkStrSplitMode splitMode,
SkTArray<SkString>* out) {
if (splitMode == kCoalesce_SkStrSplitMode) {
// Skip any delimiters.
str += strspn(str, delimiters);
}
if (!*str) {
return;
}
while (true) {
// Find a token.
const size_t len = strcspn(str, delimiters);
if (splitMode == kStrict_SkStrSplitMode || len > 0) {
out->push_back().set(str, len);
str += len;
}
if (!*str) {
return;
}
if (splitMode == kCoalesce_SkStrSplitMode) {
// Skip any delimiters.
str += strspn(str, delimiters);
} else {
// Skip one delimiter.
str += 1;
}
}
}
#undef VSNPRINTF
#undef SNPRINTF