scuffed-code/icu4c/source/common/bytestream.cpp

86 lines
2.4 KiB
C++

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
// Copyright (C) 2009-2011, International Business Machines
// Corporation and others. All Rights Reserved.
//
// Copyright 2007 Google Inc. All Rights Reserved.
// Author: sanjay@google.com (Sanjay Ghemawat)
#include "unicode/utypes.h"
#include "unicode/bytestream.h"
#include "cmemory.h"
U_NAMESPACE_BEGIN
ByteSink::~ByteSink() {}
char* ByteSink::GetAppendBuffer(int32_t min_capacity,
int32_t /*desired_capacity_hint*/,
char* scratch, int32_t scratch_capacity,
int32_t* result_capacity) {
if (min_capacity < 1 || scratch_capacity < min_capacity) {
*result_capacity = 0;
return NULL;
}
*result_capacity = scratch_capacity;
return scratch;
}
void ByteSink::Flush() {}
CheckedArrayByteSink::CheckedArrayByteSink(char* outbuf, int32_t capacity)
: outbuf_(outbuf), capacity_(capacity < 0 ? 0 : capacity),
size_(0), appended_(0), overflowed_(FALSE) {
}
CheckedArrayByteSink::~CheckedArrayByteSink() {}
CheckedArrayByteSink& CheckedArrayByteSink::Reset() {
size_ = appended_ = 0;
overflowed_ = FALSE;
return *this;
}
void CheckedArrayByteSink::Append(const char* bytes, int32_t n) {
if (n <= 0) {
return;
}
if (n > (INT32_MAX - appended_)) {
// TODO: Report as integer overflow, not merely buffer overflow.
appended_ = INT32_MAX;
overflowed_ = TRUE;
return;
}
appended_ += n;
int32_t available = capacity_ - size_;
if (n > available) {
n = available;
overflowed_ = TRUE;
}
if (n > 0 && bytes != (outbuf_ + size_)) {
uprv_memcpy(outbuf_ + size_, bytes, n);
}
size_ += n;
}
char* CheckedArrayByteSink::GetAppendBuffer(int32_t min_capacity,
int32_t /*desired_capacity_hint*/,
char* scratch,
int32_t scratch_capacity,
int32_t* result_capacity) {
if (min_capacity < 1 || scratch_capacity < min_capacity) {
*result_capacity = 0;
return NULL;
}
int32_t available = capacity_ - size_;
if (available >= min_capacity) {
*result_capacity = available;
return outbuf_ + size_;
} else {
*result_capacity = scratch_capacity;
return scratch;
}
}
U_NAMESPACE_END