/*
* Copyright (c) 2016, Chris Johns <chrisj@rtems.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/**
* @file
*
* @ingroup rtems-ld
*
* @brief A buffer of data.
*
*/
#if !defined (_RLD_BUFFER_H_)
#define _RLD_BUFFER_H_
#include <string>
#include <rld-files.h>
namespace rld
{
namespace buffer
{
/**
* A buffer to help manage formats.
*/
class buffer
{
public:
/**
* Create a buffer.
*/
buffer (const size_t size, bool le = true);
/**
* An empty buffer
*/
buffer ();
/**
* Copy a buffer.
*/
buffer (const buffer& orig);
/*
* Destory the buffer.
*/
~buffer ();
/*
* Return true if the byte order is little-endian.
*/
bool little_endian () const {
return le;
}
/**
* Clear the buffer reseting the level to zero.
*/
void clear ();
/**
* Write the data to the buffer.
*
* @param data The data to write to the buffer.
* @param length The amount of data in bytes to write.
*/
void write (const void* data_, const size_t length);
/**
* Read the data from the buffer.
*
* @param data Read from the buffer in the data.
* @param length The amount of data in bytes to read.
*/
void read (void* data_, const size_t length);
/**
* Fill the data to the buffer.
*
* @param length The amount of data in bytes to fill with.
* @param value The value to fill the buffer with.
*/
void fill (const size_t length, const uint8_t value = 0);
/**
* Set the write pointer in the buffer to the level provided filing with
* the value also provided.
*
* @param out_ The new out pointer.
* @param value The value to fill the buffer with.
*/
void set (const size_t out_, const uint8_t value = 0);
/**
* Skip the data in the buffer moving the read pointer.
*
* @param length The amount of data in bytes to skip.
*/
void skip (const size_t length);
/**
* Rewind the in pointer the buffer to the pointer.
*
* @param in_ The new in pointer.
*/
void rewind (const size_t in_);
/*
* The level in the buffer.
*/
size_t level () const;
/*
* Write the data buffered to the image. Clear the buffer after.
*/
void write (files::image& img);
/*
* Read the data from the image into the start of buffer.
*/
void read (files::image& img, size_t length = 0);
/*
* Dump.
*/
void dump ();
private:
uint8_t* data; //< The data held in the buffer.
size_t size; //< The zie of the date the buffer hold.
bool le; //< True is little endian else it is big.
size_t in; //< The data in pointer, used when writing.
size_t out; //< The data out ponter, used when reading.
size_t level_; //< The level of data in the buffer.
};
/**
* Buffer template function for writing data to the buffer.
*/
template < typename T >
void write (buffer& buf, const T value)
{
uint8_t bytes[sizeof (T)];
T v = value;
if (buf.little_endian ())
{
size_t b = sizeof (T);
while (b != 0)
{
bytes[--b] = (uint8_t) v;
v >>= 8;
}
}
else
{
size_t b = 0;
while (b < sizeof (T))
{
bytes[b++] = (uint8_t) v;
v >>= 8;
}
}
buf.write (bytes, sizeof (T));
}
/**
* Buffer template function for reading data to the buffer.
*/
template < typename T >
void read (buffer& buf, T& value)
{
uint8_t bytes[sizeof (T)];
buf.read (bytes, sizeof (T));
value = 0;
if (buf.little_endian ())
{
size_t b = sizeof (T);
while (b != 0)
{
value <<= 8;
value |= (T) bytes[--b];
}
}
else
{
size_t b = 0;
while (b < sizeof (T))
{
value <<= 8;
value |= (T) bytes[b++];
}
}
}
/*
* Insertion operators.
*/
buffer& operator<< (buffer& buf, const uint64_t value);
buffer& operator<< (buffer& buf, const uint32_t value);
buffer& operator<< (buffer& buf, const uint16_t value);
buffer& operator<< (buffer& buf, const uint8_t value);
buffer& operator<< (buffer& buf, const std::string& str);
/*
* Extraction operators.
*/
buffer& operator>> (buffer& buf, uint64_t& value);
buffer& operator>> (buffer& buf, uint32_t& value);
buffer& operator>> (buffer& buf, uint16_t& value);
buffer& operator>> (buffer& buf, uint8_t& value);
/*
* Buffer fill manipulator.
*/
struct b_fill
{
const uint8_t value;
const size_t amount;
b_fill (const size_t amount, const uint8_t value)
: value (value),
amount (amount) {
}
friend buffer& operator<< (buffer& buf, const b_fill& bf) {
buf.fill (bf.amount, bf.value);
return buf;
}
};
b_fill fill (const size_t amount, const uint8_t value = 0);
/*
* Buffer set manipulator.
*/
struct b_set
{
const uint8_t value;
const size_t level;
b_set (const size_t level, const uint8_t value)
: value (value),
level (level) {
}
friend buffer& operator<< (buffer& buf, const b_set& bs) {
buf.set (bs.level, bs.value);
return buf;
}
};
b_set set (const size_t level, const uint8_t value = 0);
/*
* Buffer skip manipulator.
*/
struct b_skip
{
const size_t amount;
b_skip (const size_t amount)
: amount (amount) {
}
friend buffer& operator>> (buffer& buf, const b_skip& bs) {
buf.skip (bs.amount);
return buf;
}
};
b_skip skip (const size_t amount);
}
}
#endif
