#include "elf.h"

bool elf64_validate(Elf64_Ehdr *ehdr, unsigned type, unsigned machine)
{
    if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
            ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
            ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
            ehdr->e_ident[EI_MAG3] != ELFMAG3 ||
            ehdr->e_ident[EI_CLASS] != ELFCLASS64 ||
            ehdr->e_ident[EI_DATA] != ELFDATA2LSB ||
            ehdr->e_ident[EI_VERSION] != EV_CURRENT ||
            ehdr->e_machine != machine ||
            ehdr->e_type != type)
    {
        return false;
    }

    return true;
}

size_t elf64_size(Elf64_Ehdr *ehdr, Elf64_Phdr *phdrs)
{
    size_t size = 0;

    for (int i = 0; i < ehdr->e_phnum; i++)
    {
        if (phdrs[i].p_type != PT_LOAD)
        {
            continue;
        }

        if (phdrs[i].p_offset + phdrs[i].p_memsz > size)
        {
            size = phdrs[i].p_offset + phdrs[i].p_memsz;
            if (phdrs[i].p_align > 1)
            {
                size = (size + phdrs[i].p_align - 1) &
                    ~(phdrs[i].p_align - 1);
            }
        }
    }

    return size;
}