AtomicGameEngine/Source/ThirdParty/TurboBadger/tb_tempbuffer.cpp

// ================================================================================
// ==      This file is a part of Turbo Badger. (C) 2011-2014, Emil Segerås      ==
// ==                     See tb_core.h for more information.                    ==
// ================================================================================

#include "tb_tempbuffer.h"
#include <assert.h>
#include <stdlib.h>
#include <memory.h>
#include <string.h>

namespace tb {

static char *p_realloc(char *buf, size_t size) { return (char *) realloc(buf, size); }
static void p_free(char *buf) { free(buf); }

TBTempBuffer::TBTempBuffer()
    : m_data(0)
    , m_data_size(0)
    , m_append_pos(0)
{
}

TBTempBuffer::~TBTempBuffer()
{
    p_free(m_data);
}

void TBTempBuffer::SetAppendPos(int append_pos)
{
    assert(append_pos >= 0 && append_pos <= m_data_size);
    m_append_pos = append_pos;
}

bool TBTempBuffer::Reserve(int size)
{
    if (size > m_data_size)
    {
        char *new_data = p_realloc(m_data, size);
        if (!new_data)
            return false;
        m_data = new_data;
        m_data_size = size;
    }
    return true;
}

int TBTempBuffer::GetAppendReserveSize(int needed_size) const
{
    // Reserve some extra memory to reduce the reserve calls.
    needed_size *= 2;
    return needed_size < 32 ? 32 : needed_size;
}

bool TBTempBuffer::Append(const char *data, int size)
{
    if (m_append_pos + size > m_data_size && !Reserve(GetAppendReserveSize(m_append_pos + size)))
        return false;
    memcpy(m_data + m_append_pos, data, size);
    m_append_pos += size;
    return true;
}

bool TBTempBuffer::AppendSpace(int size)
{
    if (m_append_pos + size > m_data_size && !Reserve(GetAppendReserveSize(m_append_pos + size)))
        return false;
    m_append_pos += size;
    return true;
}

bool TBTempBuffer::AppendString(const char *str)
{
    // Add 1 to include the null termination in the data.
    if (Append(str, strlen(str) + 1))
    {
        // Now remove the null termination from the append position
        // again, so another call will append to the same string (instead of
        // after the null termination of the first string)
        m_append_pos--;
        return true;
    }
    return false;
}

bool TBTempBuffer::AppendPath(const char *full_path_and_filename)
{
    const char *str_start = full_path_and_filename;
    while (const char *next = strpbrk(full_path_and_filename, "\\/"))
        full_path_and_filename = next + 1;

    if (str_start == full_path_and_filename) // Filename contained no path
    {
        str_start = "./";
        full_path_and_filename = str_start + 2;
    }

    int len = full_path_and_filename - str_start;
    if (Reserve(len + 1))
    {
        // Add the string, and nulltermination.
        Append(str_start, len);
        Append("", 1);
        // Remove null termination from append pos again (see details in AppendString).
        m_append_pos--;
        return true;
    }
    return false;
}

}; // namespace tb