/* Copyright 2017 - 2025 R. Thomas

* Copyright 2017 - 2025 Quarkslab

*

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

#include <algorithm>

#include <iterator>

#include <vector>

#include "LIEF/BinaryStream/FileStream.hpp"

#include "LIEF/BinaryStream/SpanStream.hpp"

#include "LIEF/ELF/utils.hpp"

#include "ELF/Structures.hpp"

namespace LIEF {

namespace ELF {

bool is_elf(BinaryStream& stream) {

using magic_t = std::array<char, sizeof(details::ElfMagic)>;

ScopedStream scoped(stream, 0);

if (auto res = scoped->peek<magic_t>()) {

const auto magic = *res;

return std::equal(std::begin(magic), std::end(magic),

std::begin(details::ElfMagic));

}

return false;

}

bool is_elf(const std::string& file) {

if (auto stream = FileStream::from_file(file)) {

return is_elf(*stream);

}

return false;

}

bool is_elf(const std::vector<uint8_t>& raw) {

if (auto stream = SpanStream::from_vector(raw)) {

return is_elf(*stream);

}

return false;

}

/// SYSV hash function

unsigned long hash32(const char* name) {

unsigned long h = 0, g;

while (*name != 0) {

h = (h << 4) + *name++;

if ((g = h & 0xf0000000) != 0u) {

h ^= g >> 24;

}

h &= ~g;

}

return h;

}

/// SYSV hash function

/// https://blogs.oracle.com/ali/entry/gnu_hash_elf_sections

unsigned long hash64(const char* name) {

unsigned long h = 0, g;

while (*name != 0) {

h = (h << 4) + *name++;

if ((g = h & 0xf0000000) != 0u) {

h ^= g >> 24;

}

h &= 0x0fffffff;

}

return h;

}

uint32_t dl_new_hash(const char* name) {

uint32_t h = 5381;

for (unsigned char c = *name; c != '\0'; c = *++name) {

h = h * 33 + c;

}

return h & 0xffffffff;

}

} // namespace ELF

} // namespace LIEF