486 lines
12 KiB
C++
486 lines
12 KiB
C++
#pragma once
|
|
|
|
#include "types.hh"
|
|
#include "logging.hh"
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <dirent.h>
|
|
#include <unistd.h>
|
|
#include <signal.h>
|
|
|
|
#include <functional>
|
|
#include <limits>
|
|
#include <cstdio>
|
|
#include <map>
|
|
|
|
#ifndef HAVE_STRUCT_DIRENT_D_TYPE
|
|
#define DT_UNKNOWN 0
|
|
#define DT_REG 1
|
|
#define DT_LNK 2
|
|
#define DT_DIR 3
|
|
#endif
|
|
|
|
namespace nix {
|
|
|
|
|
|
/* Return an environment variable. */
|
|
string getEnv(const string & key, const string & def = "");
|
|
|
|
/* Get the entire environment. */
|
|
std::map<std::string, std::string> getEnv();
|
|
|
|
/* Return an absolutized path, resolving paths relative to the
|
|
specified directory, or the current directory otherwise. The path
|
|
is also canonicalised. */
|
|
Path absPath(Path path, Path dir = "");
|
|
|
|
/* Canonicalise a path by removing all `.' or `..' components and
|
|
double or trailing slashes. Optionally resolves all symlink
|
|
components such that each component of the resulting path is *not*
|
|
a symbolic link. */
|
|
Path canonPath(const Path & path, bool resolveSymlinks = false);
|
|
|
|
/* Return the directory part of the given canonical path, i.e.,
|
|
everything before the final `/'. If the path is the root or an
|
|
immediate child thereof (e.g., `/foo'), this means an empty string
|
|
is returned. */
|
|
Path dirOf(const Path & path);
|
|
|
|
/* Return the base name of the given canonical path, i.e., everything
|
|
following the final `/'. */
|
|
string baseNameOf(const Path & path);
|
|
|
|
/* Check whether a given path is a descendant of the given
|
|
directory. */
|
|
bool isInDir(const Path & path, const Path & dir);
|
|
|
|
/* Get status of `path'. */
|
|
struct stat lstat(const Path & path);
|
|
|
|
/* Return true iff the given path exists. */
|
|
bool pathExists(const Path & path);
|
|
|
|
/* Read the contents (target) of a symbolic link. The result is not
|
|
in any way canonicalised. */
|
|
Path readLink(const Path & path);
|
|
|
|
bool isLink(const Path & path);
|
|
|
|
/* Read the contents of a directory. The entries `.' and `..' are
|
|
removed. */
|
|
struct DirEntry
|
|
{
|
|
string name;
|
|
ino_t ino;
|
|
unsigned char type; // one of DT_*
|
|
DirEntry(const string & name, ino_t ino, unsigned char type)
|
|
: name(name), ino(ino), type(type) { }
|
|
};
|
|
|
|
typedef vector<DirEntry> DirEntries;
|
|
|
|
DirEntries readDirectory(const Path & path);
|
|
|
|
unsigned char getFileType(const Path & path);
|
|
|
|
/* Read the contents of a file into a string. */
|
|
string readFile(int fd);
|
|
string readFile(const Path & path, bool drain = false);
|
|
|
|
/* Write a string to a file. */
|
|
void writeFile(const Path & path, const string & s);
|
|
|
|
/* Read a line from a file descriptor. */
|
|
string readLine(int fd);
|
|
|
|
/* Write a line to a file descriptor. */
|
|
void writeLine(int fd, string s);
|
|
|
|
/* Delete a path; i.e., in the case of a directory, it is deleted
|
|
recursively. It's not an error if the path does not exist. The
|
|
second variant returns the number of bytes and blocks freed. */
|
|
void deletePath(const Path & path);
|
|
|
|
void deletePath(const Path & path, unsigned long long & bytesFreed);
|
|
|
|
/* Create a temporary directory. */
|
|
Path createTempDir(const Path & tmpRoot = "", const Path & prefix = "nix",
|
|
bool includePid = true, bool useGlobalCounter = true, mode_t mode = 0755);
|
|
|
|
/* Return the path to $XDG_CACHE_HOME/.cache. */
|
|
Path getCacheDir();
|
|
|
|
/* Create a directory and all its parents, if necessary. Returns the
|
|
list of created directories, in order of creation. */
|
|
Paths createDirs(const Path & path);
|
|
|
|
/* Create a symlink. */
|
|
void createSymlink(const Path & target, const Path & link);
|
|
|
|
/* Atomically create or replace a symlink. */
|
|
void replaceSymlink(const Path & target, const Path & link);
|
|
|
|
|
|
/* Wrappers arount read()/write() that read/write exactly the
|
|
requested number of bytes. */
|
|
void readFull(int fd, unsigned char * buf, size_t count);
|
|
void writeFull(int fd, const unsigned char * buf, size_t count, bool allowInterrupts = true);
|
|
void writeFull(int fd, const string & s, bool allowInterrupts = true);
|
|
|
|
MakeError(EndOfFile, Error)
|
|
|
|
|
|
/* Read a file descriptor until EOF occurs. */
|
|
string drainFD(int fd);
|
|
|
|
|
|
|
|
/* Automatic cleanup of resources. */
|
|
|
|
|
|
template <class T>
|
|
struct AutoDeleteArray
|
|
{
|
|
T * p;
|
|
AutoDeleteArray(T * p) : p(p) { }
|
|
~AutoDeleteArray()
|
|
{
|
|
delete [] p;
|
|
}
|
|
};
|
|
|
|
|
|
class AutoDelete
|
|
{
|
|
Path path;
|
|
bool del;
|
|
bool recursive;
|
|
public:
|
|
AutoDelete();
|
|
AutoDelete(const Path & p, bool recursive = true);
|
|
~AutoDelete();
|
|
void cancel();
|
|
void reset(const Path & p, bool recursive = true);
|
|
operator Path() const { return path; }
|
|
};
|
|
|
|
|
|
class AutoCloseFD
|
|
{
|
|
int fd;
|
|
void close();
|
|
public:
|
|
AutoCloseFD();
|
|
AutoCloseFD(int fd);
|
|
AutoCloseFD(const AutoCloseFD & fd) = delete;
|
|
AutoCloseFD(AutoCloseFD&& fd);
|
|
~AutoCloseFD();
|
|
AutoCloseFD& operator =(const AutoCloseFD & fd) = delete;
|
|
AutoCloseFD& operator =(AutoCloseFD&& fd);
|
|
int get() const;
|
|
explicit operator bool() const;
|
|
int release();
|
|
};
|
|
|
|
|
|
class Pipe
|
|
{
|
|
public:
|
|
AutoCloseFD readSide, writeSide;
|
|
void create();
|
|
};
|
|
|
|
|
|
class AutoCloseDir
|
|
{
|
|
DIR * dir;
|
|
public:
|
|
AutoCloseDir();
|
|
AutoCloseDir(DIR * dir);
|
|
~AutoCloseDir();
|
|
void operator =(DIR * dir);
|
|
operator DIR *();
|
|
void close();
|
|
};
|
|
|
|
|
|
class Pid
|
|
{
|
|
pid_t pid;
|
|
bool separatePG;
|
|
int killSignal;
|
|
public:
|
|
Pid();
|
|
Pid(pid_t pid);
|
|
~Pid();
|
|
void operator =(pid_t pid);
|
|
operator pid_t();
|
|
void kill(bool quiet = false);
|
|
int wait(bool block);
|
|
void setSeparatePG(bool separatePG);
|
|
void setKillSignal(int signal);
|
|
pid_t release();
|
|
};
|
|
|
|
|
|
/* Kill all processes running under the specified uid by sending them
|
|
a SIGKILL. */
|
|
void killUser(uid_t uid);
|
|
|
|
|
|
/* Fork a process that runs the given function, and return the child
|
|
pid to the caller. */
|
|
struct ProcessOptions
|
|
{
|
|
string errorPrefix;
|
|
bool dieWithParent;
|
|
bool runExitHandlers;
|
|
bool allowVfork;
|
|
ProcessOptions() : errorPrefix("error: "), dieWithParent(true), runExitHandlers(false), allowVfork(true) { };
|
|
};
|
|
|
|
pid_t startProcess(std::function<void()> fun, const ProcessOptions & options = ProcessOptions());
|
|
|
|
|
|
/* Run a program and return its stdout in a string (i.e., like the
|
|
shell backtick operator). */
|
|
string runProgram(Path program, bool searchPath = false,
|
|
const Strings & args = Strings(), const string & input = "");
|
|
|
|
class ExecError : public Error
|
|
{
|
|
public:
|
|
int status;
|
|
|
|
template<typename... Args>
|
|
ExecError(int status, Args... args)
|
|
: Error(args...), status(status)
|
|
{ }
|
|
};
|
|
|
|
/* Convert a list of strings to a null-terminated vector of char
|
|
*'s. The result must not be accessed beyond the lifetime of the
|
|
list of strings. */
|
|
std::vector<char *> stringsToCharPtrs(const Strings & ss);
|
|
|
|
/* Close all file descriptors except stdin, stdout, stderr, and those
|
|
listed in the given set. Good practice in child processes. */
|
|
void closeMostFDs(const set<int> & exceptions);
|
|
|
|
/* Set the close-on-exec flag for the given file descriptor. */
|
|
void closeOnExec(int fd);
|
|
|
|
/* Restore default handling of SIGPIPE, otherwise some programs will
|
|
randomly say "Broken pipe". */
|
|
void restoreSIGPIPE();
|
|
|
|
|
|
/* User interruption. */
|
|
|
|
extern volatile sig_atomic_t _isInterrupted;
|
|
|
|
extern thread_local bool interruptThrown;
|
|
|
|
void _interrupted();
|
|
|
|
void inline checkInterrupt()
|
|
{
|
|
if (_isInterrupted) _interrupted();
|
|
}
|
|
|
|
MakeError(Interrupted, BaseError)
|
|
|
|
|
|
/* String tokenizer. */
|
|
template<class C> C tokenizeString(const string & s, const string & separators = " \t\n\r");
|
|
|
|
|
|
/* Concatenate the given strings with a separator between the
|
|
elements. */
|
|
string concatStringsSep(const string & sep, const Strings & ss);
|
|
string concatStringsSep(const string & sep, const StringSet & ss);
|
|
|
|
|
|
/* Remove trailing whitespace from a string. */
|
|
string chomp(const string & s);
|
|
|
|
|
|
/* Remove whitespace from the start and end of a string. */
|
|
string trim(const string & s, const string & whitespace = " \n\r\t");
|
|
|
|
|
|
/* Replace all occurrences of a string inside another string. */
|
|
string replaceStrings(const std::string & s,
|
|
const std::string & from, const std::string & to);
|
|
|
|
|
|
/* Convert the exit status of a child as returned by wait() into an
|
|
error string. */
|
|
string statusToString(int status);
|
|
|
|
bool statusOk(int status);
|
|
|
|
|
|
/* Parse a string into an integer. */
|
|
template<class N> bool string2Int(const string & s, N & n)
|
|
{
|
|
if (string(s, 0, 1) == "-" && !std::numeric_limits<N>::is_signed)
|
|
return false;
|
|
std::istringstream str(s);
|
|
str >> n;
|
|
return str && str.get() == EOF;
|
|
}
|
|
|
|
/* Parse a string into a float. */
|
|
template<class N> bool string2Float(const string & s, N & n)
|
|
{
|
|
std::istringstream str(s);
|
|
str >> n;
|
|
return str && str.get() == EOF;
|
|
}
|
|
|
|
|
|
/* Return true iff `s' starts with `prefix'. */
|
|
bool hasPrefix(const string & s, const string & prefix);
|
|
|
|
|
|
/* Return true iff `s' ends in `suffix'. */
|
|
bool hasSuffix(const string & s, const string & suffix);
|
|
|
|
|
|
/* Convert a string to lower case. */
|
|
std::string toLower(const std::string & s);
|
|
|
|
|
|
/* Escape a string that contains octal-encoded escape codes such as
|
|
used in /etc/fstab and /proc/mounts (e.g. "foo\040bar" decodes to
|
|
"foo bar"). */
|
|
string decodeOctalEscaped(const string & s);
|
|
|
|
|
|
/* Exception handling in destructors: print an error message, then
|
|
ignore the exception. */
|
|
void ignoreException();
|
|
|
|
|
|
/* Some ANSI escape sequences. */
|
|
#define ANSI_NORMAL "\e[0m"
|
|
#define ANSI_BOLD "\e[1m"
|
|
#define ANSI_RED "\e[31;1m"
|
|
|
|
|
|
/* Filter out ANSI escape codes from the given string. If 'nixOnly' is
|
|
set, only filter escape codes generated by Nixpkgs' stdenv (used to
|
|
denote nesting etc.). */
|
|
string filterANSIEscapes(const string & s, bool nixOnly = false);
|
|
|
|
|
|
/* Base64 encoding/decoding. */
|
|
string base64Encode(const string & s);
|
|
string base64Decode(const string & s);
|
|
|
|
|
|
/* Get a value for the specified key from an associate container, or a
|
|
default value if the key doesn't exist. */
|
|
template <class T>
|
|
string get(const T & map, const string & key, const string & def = "")
|
|
{
|
|
auto i = map.find(key);
|
|
return i == map.end() ? def : i->second;
|
|
}
|
|
|
|
|
|
/* Call 'failure' with the current exception as argument. If 'failure'
|
|
throws an exception, abort the program. */
|
|
void callFailure(const std::function<void(std::exception_ptr exc)> & failure,
|
|
std::exception_ptr exc = std::current_exception());
|
|
|
|
|
|
/* Evaluate the function 'f'. If it returns a value, call 'success'
|
|
with that value as its argument. If it or 'success' throws an
|
|
exception, call 'failure'. If 'failure' throws an exception, abort
|
|
the program. */
|
|
template<class T>
|
|
void sync2async(
|
|
const std::function<void(T)> & success,
|
|
const std::function<void(std::exception_ptr exc)> & failure,
|
|
const std::function<T()> & f)
|
|
{
|
|
try {
|
|
success(f());
|
|
} catch (...) {
|
|
callFailure(failure);
|
|
}
|
|
}
|
|
|
|
|
|
/* Call the function 'success'. If it throws an exception, call
|
|
'failure'. If that throws an exception, abort the program. */
|
|
template<class T>
|
|
void callSuccess(
|
|
const std::function<void(T)> & success,
|
|
const std::function<void(std::exception_ptr exc)> & failure,
|
|
T && arg)
|
|
{
|
|
try {
|
|
success(arg);
|
|
} catch (...) {
|
|
callFailure(failure);
|
|
}
|
|
}
|
|
|
|
|
|
/* A variant of std::istringstream that doesn't copy its string
|
|
argument. This is useful for large strings. The caller must ensure
|
|
that the string object is not destroyed while it's referenced by
|
|
this object. */
|
|
class istringbuf_nocopy : public std::streambuf
|
|
{
|
|
const std::string & s;
|
|
decltype(s.size()) off;
|
|
decltype(s.size()) size;
|
|
public:
|
|
istringbuf_nocopy(const std::string & s) : s{s}, off{0}, size{s.size()}
|
|
{
|
|
}
|
|
|
|
private:
|
|
int_type underflow()
|
|
{
|
|
if (off == size)
|
|
return traits_type::eof();
|
|
return traits_type::to_int_type(s[off]);
|
|
}
|
|
|
|
int_type uflow()
|
|
{
|
|
if (off == size)
|
|
return traits_type::eof();
|
|
return traits_type::to_int_type(s[off++]);
|
|
}
|
|
|
|
int_type pbackfail(int_type ch)
|
|
{
|
|
if (off == 0 || (ch != traits_type::eof() && ch != s[off - 1]))
|
|
return traits_type::eof();
|
|
|
|
return traits_type::to_int_type(s[--off]);
|
|
}
|
|
|
|
std::streamsize showmanyc()
|
|
{
|
|
return size - off;
|
|
}
|
|
};
|
|
|
|
|
|
struct istringstream_nocopy : public std::iostream
|
|
{
|
|
istringbuf_nocopy buf;
|
|
istringstream_nocopy(const std::string & s) : std::iostream(&buf), buf(s) {};
|
|
};
|
|
|
|
|
|
}
|