// Copyright 2024 The Dawn & Tint Authors
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
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// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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// GEN_BUILD:CONDITION(tint_build_is_linux)

#include "src/tint/utils/system/executable_path.h"

#include <unistd.h>
#include <filesystem>

#include "src/tint/utils/containers/vector.h"

std::string tint::ExecutablePath() {
    tint::Vector<char, 1024> buff;
    buff.Resize(1024, 0);
    while (true) {
        ssize_t result = readlink("/proc/self/exe", &buff[0], buff.Length());
        if (result == static_cast<ssize_t>(buff.Length())) {
            buff.Resize(buff.Length() * 2, 0);
        } else {
            break;
        }
    }
    return &buff[0];
}

std::string tint::ExecutableDirectory() {
    return std::filesystem::path{ExecutablePath()}.remove_filename().string();
}