Implement ByteBuffer (#6878)

esphome/core/bytebuffer.cpp

@@ -0,0 +1,134 @@
+#include "bytebuffer.h"
+#include <cassert>
+
+namespace esphome {
+
+ByteBuffer ByteBuffer::create(size_t capacity) {
+  std::vector<uint8_t> data(capacity);
+  return {data};
+}
+
+ByteBuffer ByteBuffer::wrap(uint8_t *ptr, size_t len) {
+  std::vector<uint8_t> data(ptr, ptr + len);
+  return {data};
+}
+
+ByteBuffer ByteBuffer::wrap(std::vector<uint8_t> data) { return {std::move(data)}; }
+
+void ByteBuffer::set_limit(size_t limit) {
+  assert(limit <= this->get_capacity());
+  this->limit_ = limit;
+}
+void ByteBuffer::set_position(size_t position) {
+  assert(position <= this->get_limit());
+  this->position_ = position;
+}
+void ByteBuffer::clear() {
+  this->limit_ = this->get_capacity();
+  this->position_ = 0;
+}
+uint16_t ByteBuffer::get_uint16() {
+  assert(this->get_remaining() >= 2);
+  uint16_t value;
+  if (endianness_ == LITTLE) {
+    value = this->data_[this->position_++];
+    value |= this->data_[this->position_++] << 8;
+  } else {
+    value = this->data_[this->position_++] << 8;
+    value |= this->data_[this->position_++];
+  }
+  return value;
+}
+
+uint32_t ByteBuffer::get_uint32() {
+  assert(this->get_remaining() >= 4);
+  uint32_t value;
+  if (endianness_ == LITTLE) {
+    value = this->data_[this->position_++];
+    value |= this->data_[this->position_++] << 8;
+    value |= this->data_[this->position_++] << 16;
+    value |= this->data_[this->position_++] << 24;
+  } else {
+    value = this->data_[this->position_++] << 24;
+    value |= this->data_[this->position_++] << 16;
+    value |= this->data_[this->position_++] << 8;
+    value |= this->data_[this->position_++];
+  }
+  return value;
+}
+uint32_t ByteBuffer::get_uint24() {
+  assert(this->get_remaining() >= 3);
+  uint32_t value;
+  if (endianness_ == LITTLE) {
+    value = this->data_[this->position_++];
+    value |= this->data_[this->position_++] << 8;
+    value |= this->data_[this->position_++] << 16;
+  } else {
+    value = this->data_[this->position_++] << 16;
+    value |= this->data_[this->position_++] << 8;
+    value |= this->data_[this->position_++];
+  }
+  return value;
+}
+uint32_t ByteBuffer::get_int24() {
+  auto value = this->get_uint24();
+  uint32_t mask = (~(uint32_t) 0) << 23;
+  if ((value & mask) != 0)
+    value |= mask;
+  return value;
+}
+uint8_t ByteBuffer::get_uint8() {
+  assert(this->get_remaining() >= 1);
+  return this->data_[this->position_++];
+}
+float ByteBuffer::get_float() {
+  auto value = this->get_uint32();
+  return *(float *) &value;
+}
+void ByteBuffer::put_uint8(uint8_t value) {
+  assert(this->get_remaining() >= 1);
+  this->data_[this->position_++] = value;
+}
+
+void ByteBuffer::put_uint16(uint16_t value) {
+  assert(this->get_remaining() >= 2);
+  if (this->endianness_ == LITTLE) {
+    this->data_[this->position_++] = (uint8_t) value;
+    this->data_[this->position_++] = (uint8_t) (value >> 8);
+  } else {
+    this->data_[this->position_++] = (uint8_t) (value >> 8);
+    this->data_[this->position_++] = (uint8_t) value;
+  }
+}
+void ByteBuffer::put_uint24(uint32_t value) {
+  assert(this->get_remaining() >= 3);
+  if (this->endianness_ == LITTLE) {
+    this->data_[this->position_++] = (uint8_t) value;
+    this->data_[this->position_++] = (uint8_t) (value >> 8);
+    this->data_[this->position_++] = (uint8_t) (value >> 16);
+  } else {
+    this->data_[this->position_++] = (uint8_t) (value >> 16);
+    this->data_[this->position_++] = (uint8_t) (value >> 8);
+    this->data_[this->position_++] = (uint8_t) value;
+  }
+}
+void ByteBuffer::put_uint32(uint32_t value) {
+  assert(this->get_remaining() >= 4);
+  if (this->endianness_ == LITTLE) {
+    this->data_[this->position_++] = (uint8_t) value;
+    this->data_[this->position_++] = (uint8_t) (value >> 8);
+    this->data_[this->position_++] = (uint8_t) (value >> 16);
+    this->data_[this->position_++] = (uint8_t) (value >> 24);
+  } else {
+    this->data_[this->position_++] = (uint8_t) (value >> 24);
+    this->data_[this->position_++] = (uint8_t) (value >> 16);
+    this->data_[this->position_++] = (uint8_t) (value >> 8);
+    this->data_[this->position_++] = (uint8_t) value;
+  }
+}
+void ByteBuffer::put_float(float value) { this->put_uint32(*(uint32_t *) &value); }
+void ByteBuffer::flip() {
+  this->limit_ = this->position_;
+  this->position_ = 0;
+}
+}  // namespace esphome