Function ImFileLoadToMemory

src/external/imgui/imgui.cpp:2081–2118

Helper: Load file content into memory Memory allocated with IM_ALLOC(), must be freed by user using IM_FREE() == ImGui::MemFree() This can't really be used with "rt" because fseek size won't match read size.

// Memory allocated with IM_ALLOC(), must be freed by user using IM_FREE() == ImGui::MemFree()
// This can't really be used with "rt" because fseek size won't match read size.
void*   ImFileLoadToMemory(const char* filename, const char* mode, size_t* out_file_size, int padding_bytes)
{
    IM_ASSERT(filename && mode);
    if (out_file_size)
        *out_file_size = 0;

    ImFileHandle f;
    if ((f = ImFileOpen(filename, mode)) == NULL)
        return NULL;

    size_t file_size = (size_t)ImFileGetSize(f);
    if (file_size == (size_t)-1)
    {
        ImFileClose(f);
        return NULL;
    }

    void* file_data = IM_ALLOC(file_size + padding_bytes);
    if (file_data == NULL)
    {
        ImFileClose(f);
        return NULL;
    }
    if (ImFileRead(file_data, 1, file_size, f) != file_size)
    {
        ImFileClose(f);
        IM_FREE(file_data);
        return NULL;
    }
    if (padding_bytes > 0)
        memset((void*)(((char*)file_data) + file_size), 0, (size_t)padding_bytes);

    ImFileClose(f);
    if (out_file_size)
        *out_file_size = file_size;

    return file_data;
}

//-----------------------------------------------------------------------------
// [SECTION] MISC HELPERS/UTILITIES (ImText* functions)