util.h

// Copyright (C) 2019 by Yuri Victorovich. All rights reserved.

#pragma once

#include <string>
#include <vector>
#include <set>
#include <iostream>
#include <sstream>
#include <memory>
#include <functional>

#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>

#include <rang.hpp>

//
// utility macros useful throughout the program
//

#define STR(msg...) \
  ([&]() { \
    std::ostringstream ss; \
    ss << msg; \
    return ss.str(); \
  }())
#define STRg(msg...) \
  ([]() { \
    std::ostringstream ss; \
    ss << msg; \
    return ss.str(); \
  }())
#define CSTR(msg...) (STR(msg).c_str())


template<typename T>
inline std::ostream& operator<<(std::ostream &os, const std::vector<T> &v) {
  bool fst = true;
  for (auto &e : v) {
    if (fst)
      fst = false;
    else
      os << " ";
    os << e;
  }
  return os;
}

template<typename T>
inline std::vector<T> operator+(const std::vector<T> &v1, const std::vector<T> &v2) {
  std::vector<T> res = v1;
  res.insert(res.end(), v2.begin(), v2.end());
  return res;
}

class Run {
public:
  Run(const std::function<void()> &fnAction) { fnAction(); }
};

class OnDestroy {
  std::function<void()> fnAction;
public:
  OnDestroy(const std::function<void()> &newFnAction);
  ~OnDestroy();
  void doNow();
};

class RunAtEnd : public std::unique_ptr<OnDestroy> {
public:
  RunAtEnd();
  RunAtEnd(const std::function<void()> &newFnAction);
  void reset(const std::function<void()> &newFnAction);
  void doNow();
};

//
// utility functions
//

namespace Util {

void runCommand(const std::string &cmd, const std::string &what);
std::string runCommandGetOutput(const std::string &cmd, const std::string &what);
void ckSyscallError(int res, const char *syscall, const char *arg, const std::function<bool(int)> whiteWash = [](int err) {return false;});
std::string tmSecMs();
std::string filePathToBareName(const std::string &path);
std::string filePathToFileName(const std::string &path);
int getSysctlInt(const char *name);
void setSysctlInt(const char *name, int value);
std::string getSysctlString(const char *name);
void ensureKernelModuleIsLoaded(const char *name);
std::string gethostname();
std::vector<std::string> splitString(const std::string &str, const std::string &delimiter);
std::string stripTrailingSpace(const std::string &str);
unsigned toUInt(const std::string &str);
std::string pathSubstituteVarsInPath(const std::string &path);
std::string pathSubstituteVarsInString(const std::string &str);
std::vector<std::string> reverseVector(const std::vector<std::string> &v);

namespace Fs {

bool fileExists(const std::string &path);
bool dirExists(const std::string &path);
std::vector<std::string> readFileLines(int fd);
size_t getFileSize(int fd);
void writeFile(const std::string &data, int fd);
void writeFile(const std::string &data, const std::string &file);
void appendFile(const std::string &data, const std::string &file);
void chmod(const std::string &path, mode_t mode);
void chown(const std::string &path, uid_t owner, gid_t group);
void link(const std::string &name1, const std::string &name2);
void unlink(const std::string &file);
void mkdir(const std::string &dir, mode_t mode);
void rmdir(const std::string &dir);
void rmdirFlat(const std::string &dir);
void rmdirHier(const std::string &dir);
bool rmdirFlatExcept(const std::string &dir, const std::set<std::string> &except);
bool rmdirHierExcept(const std::string &dir, const std::set<std::string> &except);
bool isXzArchive(const char *file);
char isElfFileOrDir(const std::string &file); // returns 'E'LF, 'D'ir, or 'N'o
std::set<std::string> findElfFiles(const std::string &dir);
bool hasExtension(const char *file, const char *extension);
void copyFile(const std::string &srcFile, const std::string &dstFile);
std::vector<std::string> expandWildcards(const std::string &wildcardPath, const std::string &cmdPrefix = "");

}

}