forked from lix-project/lix
1308 lines
30 KiB
C++
1308 lines
30 KiB
C++
#include "util.hh"
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#include "affinity.hh"
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#include "sync.hh"
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#include "finally.hh"
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#include <cctype>
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#include <cerrno>
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#include <cstdio>
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#include <cstdlib>
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#include <cstring>
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#include <iostream>
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#include <sstream>
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#include <thread>
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#include <future>
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#include <sys/wait.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <limits.h>
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#ifdef __APPLE__
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#include <sys/syscall.h>
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#endif
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#ifdef __linux__
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#include <sys/prctl.h>
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#endif
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extern char * * environ;
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namespace nix {
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BaseError & BaseError::addPrefix(const FormatOrString & fs)
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{
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prefix_ = fs.s + prefix_;
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return *this;
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}
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std::string SysError::addErrno(const std::string & s)
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{
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errNo = errno;
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return s + ": " + strerror(errNo);
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}
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string getEnv(const string & key, const string & def)
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{
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char * value = getenv(key.c_str());
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return value ? string(value) : def;
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}
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std::map<std::string, std::string> getEnv()
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{
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std::map<std::string, std::string> env;
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for (size_t i = 0; environ[i]; ++i) {
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auto s = environ[i];
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auto eq = strchr(s, '=');
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if (!eq)
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// invalid env, just keep going
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continue;
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env.emplace(std::string(s, eq), std::string(eq + 1));
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}
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return env;
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}
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Path absPath(Path path, Path dir)
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{
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if (path[0] != '/') {
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if (dir == "") {
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#ifdef __GNU__
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/* GNU (aka. GNU/Hurd) doesn't have any limitation on path
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lengths and doesn't define `PATH_MAX'. */
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char *buf = getcwd(NULL, 0);
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if (buf == NULL)
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#else
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char buf[PATH_MAX];
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if (!getcwd(buf, sizeof(buf)))
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#endif
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throw SysError("cannot get cwd");
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dir = buf;
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#ifdef __GNU__
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free(buf);
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#endif
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}
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path = dir + "/" + path;
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}
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return canonPath(path);
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}
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Path canonPath(const Path & path, bool resolveSymlinks)
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{
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assert(path != "");
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string s;
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if (path[0] != '/')
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throw Error(format("not an absolute path: ‘%1%’") % path);
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string::const_iterator i = path.begin(), end = path.end();
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string temp;
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/* Count the number of times we follow a symlink and stop at some
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arbitrary (but high) limit to prevent infinite loops. */
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unsigned int followCount = 0, maxFollow = 1024;
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while (1) {
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/* Skip slashes. */
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while (i != end && *i == '/') i++;
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if (i == end) break;
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/* Ignore `.'. */
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if (*i == '.' && (i + 1 == end || i[1] == '/'))
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i++;
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/* If `..', delete the last component. */
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else if (*i == '.' && i + 1 < end && i[1] == '.' &&
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(i + 2 == end || i[2] == '/'))
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{
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if (!s.empty()) s.erase(s.rfind('/'));
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i += 2;
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}
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/* Normal component; copy it. */
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else {
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s += '/';
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while (i != end && *i != '/') s += *i++;
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/* If s points to a symlink, resolve it and restart (since
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the symlink target might contain new symlinks). */
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if (resolveSymlinks && isLink(s)) {
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if (++followCount >= maxFollow)
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throw Error(format("infinite symlink recursion in path ‘%1%’") % path);
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temp = absPath(readLink(s), dirOf(s))
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+ string(i, end);
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i = temp.begin(); /* restart */
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end = temp.end();
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s = "";
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}
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}
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}
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return s.empty() ? "/" : s;
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}
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Path dirOf(const Path & path)
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{
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Path::size_type pos = path.rfind('/');
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if (pos == string::npos)
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throw Error(format("invalid file name ‘%1%’") % path);
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return pos == 0 ? "/" : Path(path, 0, pos);
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}
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string baseNameOf(const Path & path)
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{
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if (path.empty())
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return "";
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Path::size_type last = path.length() - 1;
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if (path[last] == '/' && last > 0)
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last -= 1;
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Path::size_type pos = path.rfind('/', last);
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if (pos == string::npos)
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pos = 0;
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else
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pos += 1;
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return string(path, pos, last - pos + 1);
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}
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bool isInDir(const Path & path, const Path & dir)
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{
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return path[0] == '/'
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&& string(path, 0, dir.size()) == dir
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&& path.size() >= dir.size() + 2
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&& path[dir.size()] == '/';
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}
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struct stat lstat(const Path & path)
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{
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struct stat st;
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if (lstat(path.c_str(), &st))
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throw SysError(format("getting status of ‘%1%’") % path);
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return st;
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}
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bool pathExists(const Path & path)
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{
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int res;
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struct stat st;
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res = lstat(path.c_str(), &st);
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if (!res) return true;
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if (errno != ENOENT && errno != ENOTDIR)
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throw SysError(format("getting status of %1%") % path);
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return false;
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}
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Path readLink(const Path & path)
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{
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checkInterrupt();
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struct stat st = lstat(path);
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if (!S_ISLNK(st.st_mode))
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throw Error(format("‘%1%’ is not a symlink") % path);
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char buf[st.st_size];
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ssize_t rlsize = readlink(path.c_str(), buf, st.st_size);
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if (rlsize == -1)
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throw SysError(format("reading symbolic link ‘%1%’") % path);
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else if (rlsize > st.st_size)
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throw Error(format("symbolic link ‘%1%’ size overflow %2% > %3%")
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% path % rlsize % st.st_size);
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return string(buf, rlsize);
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}
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bool isLink(const Path & path)
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{
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struct stat st = lstat(path);
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return S_ISLNK(st.st_mode);
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}
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DirEntries readDirectory(const Path & path)
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{
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DirEntries entries;
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entries.reserve(64);
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AutoCloseDir dir(opendir(path.c_str()));
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if (!dir) throw SysError(format("opening directory ‘%1%’") % path);
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struct dirent * dirent;
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while (errno = 0, dirent = readdir(dir.get())) { /* sic */
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checkInterrupt();
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string name = dirent->d_name;
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if (name == "." || name == "..") continue;
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entries.emplace_back(name, dirent->d_ino,
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#ifdef HAVE_STRUCT_DIRENT_D_TYPE
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dirent->d_type
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#else
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DT_UNKNOWN
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#endif
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);
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}
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if (errno) throw SysError(format("reading directory ‘%1%’") % path);
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return entries;
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}
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unsigned char getFileType(const Path & path)
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{
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struct stat st = lstat(path);
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if (S_ISDIR(st.st_mode)) return DT_DIR;
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if (S_ISLNK(st.st_mode)) return DT_LNK;
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if (S_ISREG(st.st_mode)) return DT_REG;
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return DT_UNKNOWN;
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}
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string readFile(int fd)
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{
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struct stat st;
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if (fstat(fd, &st) == -1)
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throw SysError("statting file");
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auto buf = std::make_unique<unsigned char[]>(st.st_size);
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readFull(fd, buf.get(), st.st_size);
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return string((char *) buf.get(), st.st_size);
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}
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string readFile(const Path & path, bool drain)
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{
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AutoCloseFD fd = open(path.c_str(), O_RDONLY | O_CLOEXEC);
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if (!fd)
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throw SysError(format("opening file ‘%1%’") % path);
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return drain ? drainFD(fd.get()) : readFile(fd.get());
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}
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void writeFile(const Path & path, const string & s, mode_t mode)
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{
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AutoCloseFD fd = open(path.c_str(), O_WRONLY | O_TRUNC | O_CREAT | O_CLOEXEC, mode);
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if (!fd)
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throw SysError(format("opening file ‘%1%’") % path);
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writeFull(fd.get(), s);
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}
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string readLine(int fd)
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{
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string s;
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while (1) {
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checkInterrupt();
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char ch;
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ssize_t rd = read(fd, &ch, 1);
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if (rd == -1) {
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if (errno != EINTR)
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throw SysError("reading a line");
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} else if (rd == 0)
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throw EndOfFile("unexpected EOF reading a line");
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else {
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if (ch == '\n') return s;
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s += ch;
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}
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}
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}
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void writeLine(int fd, string s)
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{
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s += '\n';
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writeFull(fd, s);
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}
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static void _deletePath(const Path & path, unsigned long long & bytesFreed)
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{
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checkInterrupt();
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struct stat st;
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if (lstat(path.c_str(), &st) == -1) {
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if (errno == ENOENT) return;
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throw SysError(format("getting status of ‘%1%’") % path);
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}
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if (!S_ISDIR(st.st_mode) && st.st_nlink == 1)
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bytesFreed += st.st_blocks * 512;
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if (S_ISDIR(st.st_mode)) {
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/* Make the directory accessible. */
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const auto PERM_MASK = S_IRUSR | S_IWUSR | S_IXUSR;
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if ((st.st_mode & PERM_MASK) != PERM_MASK) {
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if (chmod(path.c_str(), st.st_mode | PERM_MASK) == -1)
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throw SysError(format("chmod ‘%1%’") % path);
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}
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for (auto & i : readDirectory(path))
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_deletePath(path + "/" + i.name, bytesFreed);
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}
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if (remove(path.c_str()) == -1) {
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if (errno == ENOENT) return;
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throw SysError(format("cannot unlink ‘%1%’") % path);
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}
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}
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void deletePath(const Path & path)
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{
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unsigned long long dummy;
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deletePath(path, dummy);
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}
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void deletePath(const Path & path, unsigned long long & bytesFreed)
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{
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Activity act(*logger, lvlDebug, format("recursively deleting path ‘%1%’") % path);
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bytesFreed = 0;
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_deletePath(path, bytesFreed);
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}
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static Path tempName(Path tmpRoot, const Path & prefix, bool includePid,
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int & counter)
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{
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tmpRoot = canonPath(tmpRoot.empty() ? getEnv("TMPDIR", "/tmp") : tmpRoot, true);
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if (includePid)
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return (format("%1%/%2%-%3%-%4%") % tmpRoot % prefix % getpid() % counter++).str();
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else
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return (format("%1%/%2%-%3%") % tmpRoot % prefix % counter++).str();
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}
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Path createTempDir(const Path & tmpRoot, const Path & prefix,
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bool includePid, bool useGlobalCounter, mode_t mode)
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{
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static int globalCounter = 0;
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int localCounter = 0;
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int & counter(useGlobalCounter ? globalCounter : localCounter);
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while (1) {
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checkInterrupt();
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Path tmpDir = tempName(tmpRoot, prefix, includePid, counter);
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if (mkdir(tmpDir.c_str(), mode) == 0) {
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#if __FreeBSD__
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/* Explicitly set the group of the directory. This is to
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work around around problems caused by BSD's group
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ownership semantics (directories inherit the group of
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the parent). For instance, the group of /tmp on
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FreeBSD is "wheel", so all directories created in /tmp
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will be owned by "wheel"; but if the user is not in
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"wheel", then "tar" will fail to unpack archives that
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have the setgid bit set on directories. */
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if (chown(tmpDir.c_str(), (uid_t) -1, getegid()) != 0)
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throw SysError(format("setting group of directory ‘%1%’") % tmpDir);
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#endif
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return tmpDir;
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}
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if (errno != EEXIST)
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throw SysError(format("creating directory ‘%1%’") % tmpDir);
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}
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}
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Path getCacheDir()
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{
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Path cacheDir = getEnv("XDG_CACHE_HOME");
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if (cacheDir.empty()) {
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Path homeDir = getEnv("HOME");
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if (homeDir.empty()) throw Error("$XDG_CACHE_HOME and $HOME are not set");
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cacheDir = homeDir + "/.cache";
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}
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return cacheDir;
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}
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Path getConfigDir()
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{
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Path configDir = getEnv("XDG_CONFIG_HOME");
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if (configDir.empty()) {
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Path homeDir = getEnv("HOME");
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if (homeDir.empty()) throw Error("$XDG_CONFIG_HOME and $HOME are not set");
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configDir = homeDir + "/.config";
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}
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return configDir;
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}
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Path getDataDir()
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{
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Path dataDir = getEnv("XDG_DATA_HOME");
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if (dataDir.empty()) {
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Path homeDir = getEnv("HOME");
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if (homeDir.empty()) throw Error("$XDG_DATA_HOME and $HOME are not set");
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dataDir = homeDir + "/.local/share";
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}
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return dataDir;
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}
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Paths createDirs(const Path & path)
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{
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Paths created;
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if (path == "/") return created;
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struct stat st;
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if (lstat(path.c_str(), &st) == -1) {
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created = createDirs(dirOf(path));
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if (mkdir(path.c_str(), 0777) == -1 && errno != EEXIST)
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throw SysError(format("creating directory ‘%1%’") % path);
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st = lstat(path);
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created.push_back(path);
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}
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if (S_ISLNK(st.st_mode) && stat(path.c_str(), &st) == -1)
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throw SysError(format("statting symlink ‘%1%’") % path);
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if (!S_ISDIR(st.st_mode)) throw Error(format("‘%1%’ is not a directory") % path);
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return created;
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}
|
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|
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void createSymlink(const Path & target, const Path & link)
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{
|
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if (symlink(target.c_str(), link.c_str()))
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throw SysError(format("creating symlink from ‘%1%’ to ‘%2%’") % link % target);
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}
|
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|
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|
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void replaceSymlink(const Path & target, const Path & link)
|
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{
|
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Path tmp = canonPath(dirOf(link) + "/.new_" + baseNameOf(link));
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|
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createSymlink(target, tmp);
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|
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if (rename(tmp.c_str(), link.c_str()) != 0)
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throw SysError(format("renaming ‘%1%’ to ‘%2%’") % tmp % link);
|
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}
|
||
|
||
|
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void readFull(int fd, unsigned char * buf, size_t count)
|
||
{
|
||
while (count) {
|
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checkInterrupt();
|
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ssize_t res = read(fd, (char *) buf, count);
|
||
if (res == -1) {
|
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if (errno == EINTR) continue;
|
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throw SysError("reading from file");
|
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}
|
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if (res == 0) throw EndOfFile("unexpected end-of-file");
|
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count -= res;
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buf += res;
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}
|
||
}
|
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|
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|
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void writeFull(int fd, const unsigned char * buf, size_t count, bool allowInterrupts)
|
||
{
|
||
while (count) {
|
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if (allowInterrupts) checkInterrupt();
|
||
ssize_t res = write(fd, (char *) buf, count);
|
||
if (res == -1 && errno != EINTR)
|
||
throw SysError("writing to file");
|
||
if (res > 0) {
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count -= res;
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buf += res;
|
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}
|
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}
|
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}
|
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|
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|
||
void writeFull(int fd, const string & s, bool allowInterrupts)
|
||
{
|
||
writeFull(fd, (const unsigned char *) s.data(), s.size(), allowInterrupts);
|
||
}
|
||
|
||
|
||
string drainFD(int fd)
|
||
{
|
||
string result;
|
||
unsigned char buffer[4096];
|
||
while (1) {
|
||
checkInterrupt();
|
||
ssize_t rd = read(fd, buffer, sizeof buffer);
|
||
if (rd == -1) {
|
||
if (errno != EINTR)
|
||
throw SysError("reading from file");
|
||
}
|
||
else if (rd == 0) break;
|
||
else result.append((char *) buffer, rd);
|
||
}
|
||
return result;
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
AutoDelete::AutoDelete() : del{false} {}
|
||
|
||
AutoDelete::AutoDelete(const string & p, bool recursive) : path(p)
|
||
{
|
||
del = true;
|
||
this->recursive = recursive;
|
||
}
|
||
|
||
AutoDelete::~AutoDelete()
|
||
{
|
||
try {
|
||
if (del) {
|
||
if (recursive)
|
||
deletePath(path);
|
||
else {
|
||
if (remove(path.c_str()) == -1)
|
||
throw SysError(format("cannot unlink ‘%1%’") % path);
|
||
}
|
||
}
|
||
} catch (...) {
|
||
ignoreException();
|
||
}
|
||
}
|
||
|
||
void AutoDelete::cancel()
|
||
{
|
||
del = false;
|
||
}
|
||
|
||
void AutoDelete::reset(const Path & p, bool recursive) {
|
||
path = p;
|
||
this->recursive = recursive;
|
||
del = true;
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
AutoCloseFD::AutoCloseFD() : fd{-1} {}
|
||
|
||
|
||
AutoCloseFD::AutoCloseFD(int fd) : fd{fd} {}
|
||
|
||
|
||
AutoCloseFD::AutoCloseFD(AutoCloseFD&& that) : fd{that.fd}
|
||
{
|
||
that.fd = -1;
|
||
}
|
||
|
||
|
||
AutoCloseFD& AutoCloseFD::operator =(AutoCloseFD&& that)
|
||
{
|
||
close();
|
||
fd = that.fd;
|
||
that.fd = -1;
|
||
return *this;
|
||
}
|
||
|
||
|
||
AutoCloseFD::~AutoCloseFD()
|
||
{
|
||
try {
|
||
close();
|
||
} catch (...) {
|
||
ignoreException();
|
||
}
|
||
}
|
||
|
||
|
||
int AutoCloseFD::get() const
|
||
{
|
||
return fd;
|
||
}
|
||
|
||
|
||
void AutoCloseFD::close()
|
||
{
|
||
if (fd != -1) {
|
||
if (::close(fd) == -1)
|
||
/* This should never happen. */
|
||
throw SysError(format("closing file descriptor %1%") % fd);
|
||
}
|
||
}
|
||
|
||
|
||
AutoCloseFD::operator bool() const
|
||
{
|
||
return fd != -1;
|
||
}
|
||
|
||
|
||
int AutoCloseFD::release()
|
||
{
|
||
int oldFD = fd;
|
||
fd = -1;
|
||
return oldFD;
|
||
}
|
||
|
||
|
||
void Pipe::create()
|
||
{
|
||
int fds[2];
|
||
#if HAVE_PIPE2
|
||
if (pipe2(fds, O_CLOEXEC) != 0) throw SysError("creating pipe");
|
||
#else
|
||
if (pipe(fds) != 0) throw SysError("creating pipe");
|
||
closeOnExec(fds[0]);
|
||
closeOnExec(fds[1]);
|
||
#endif
|
||
readSide = fds[0];
|
||
writeSide = fds[1];
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
Pid::Pid()
|
||
{
|
||
}
|
||
|
||
|
||
Pid::Pid(pid_t pid)
|
||
: pid(pid)
|
||
{
|
||
}
|
||
|
||
|
||
Pid::~Pid()
|
||
{
|
||
if (pid != -1) kill();
|
||
}
|
||
|
||
|
||
void Pid::operator =(pid_t pid)
|
||
{
|
||
if (this->pid != -1 && this->pid != pid) kill();
|
||
this->pid = pid;
|
||
killSignal = SIGKILL; // reset signal to default
|
||
}
|
||
|
||
|
||
Pid::operator pid_t()
|
||
{
|
||
return pid;
|
||
}
|
||
|
||
|
||
int Pid::kill()
|
||
{
|
||
assert(pid != -1);
|
||
|
||
debug(format("killing process %1%") % pid);
|
||
|
||
/* Send the requested signal to the child. If it has its own
|
||
process group, send the signal to every process in the child
|
||
process group (which hopefully includes *all* its children). */
|
||
if (::kill(separatePG ? -pid : pid, killSignal) != 0)
|
||
printError((SysError(format("killing process %1%") % pid).msg()));
|
||
|
||
return wait();
|
||
}
|
||
|
||
|
||
int Pid::wait()
|
||
{
|
||
assert(pid != -1);
|
||
while (1) {
|
||
int status;
|
||
int res = waitpid(pid, &status, 0);
|
||
if (res == pid) {
|
||
pid = -1;
|
||
return status;
|
||
}
|
||
if (errno != EINTR)
|
||
throw SysError("cannot get child exit status");
|
||
checkInterrupt();
|
||
}
|
||
}
|
||
|
||
|
||
void Pid::setSeparatePG(bool separatePG)
|
||
{
|
||
this->separatePG = separatePG;
|
||
}
|
||
|
||
|
||
void Pid::setKillSignal(int signal)
|
||
{
|
||
this->killSignal = signal;
|
||
}
|
||
|
||
|
||
pid_t Pid::release()
|
||
{
|
||
pid_t p = pid;
|
||
pid = -1;
|
||
return p;
|
||
}
|
||
|
||
|
||
void killUser(uid_t uid)
|
||
{
|
||
debug(format("killing all processes running under uid ‘%1%’") % uid);
|
||
|
||
assert(uid != 0); /* just to be safe... */
|
||
|
||
/* The system call kill(-1, sig) sends the signal `sig' to all
|
||
users to which the current process can send signals. So we
|
||
fork a process, switch to uid, and send a mass kill. */
|
||
|
||
ProcessOptions options;
|
||
options.allowVfork = false;
|
||
|
||
Pid pid = startProcess([&]() {
|
||
|
||
if (setuid(uid) == -1)
|
||
throw SysError("setting uid");
|
||
|
||
while (true) {
|
||
#ifdef __APPLE__
|
||
/* OSX's kill syscall takes a third parameter that, among
|
||
other things, determines if kill(-1, signo) affects the
|
||
calling process. In the OSX libc, it's set to true,
|
||
which means "follow POSIX", which we don't want here
|
||
*/
|
||
if (syscall(SYS_kill, -1, SIGKILL, false) == 0) break;
|
||
#else
|
||
if (kill(-1, SIGKILL) == 0) break;
|
||
#endif
|
||
if (errno == ESRCH) break; /* no more processes */
|
||
if (errno != EINTR)
|
||
throw SysError(format("cannot kill processes for uid ‘%1%’") % uid);
|
||
}
|
||
|
||
_exit(0);
|
||
}, options);
|
||
|
||
int status = pid.wait();
|
||
if (status != 0)
|
||
throw Error(format("cannot kill processes for uid ‘%1%’: %2%") % uid % statusToString(status));
|
||
|
||
/* !!! We should really do some check to make sure that there are
|
||
no processes left running under `uid', but there is no portable
|
||
way to do so (I think). The most reliable way may be `ps -eo
|
||
uid | grep -q $uid'. */
|
||
}
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
/* Wrapper around vfork to prevent the child process from clobbering
|
||
the caller's stack frame in the parent. */
|
||
static pid_t doFork(bool allowVfork, std::function<void()> fun) __attribute__((noinline));
|
||
static pid_t doFork(bool allowVfork, std::function<void()> fun)
|
||
{
|
||
#ifdef __linux__
|
||
pid_t pid = allowVfork ? vfork() : fork();
|
||
#else
|
||
pid_t pid = fork();
|
||
#endif
|
||
if (pid != 0) return pid;
|
||
fun();
|
||
abort();
|
||
}
|
||
|
||
|
||
pid_t startProcess(std::function<void()> fun, const ProcessOptions & options)
|
||
{
|
||
auto wrapper = [&]() {
|
||
if (!options.allowVfork)
|
||
logger = makeDefaultLogger();
|
||
try {
|
||
#if __linux__
|
||
if (options.dieWithParent && prctl(PR_SET_PDEATHSIG, SIGKILL) == -1)
|
||
throw SysError("setting death signal");
|
||
#endif
|
||
restoreAffinity();
|
||
fun();
|
||
} catch (std::exception & e) {
|
||
try {
|
||
std::cerr << options.errorPrefix << e.what() << "\n";
|
||
} catch (...) { }
|
||
} catch (...) { }
|
||
if (options.runExitHandlers)
|
||
exit(1);
|
||
else
|
||
_exit(1);
|
||
};
|
||
|
||
pid_t pid = doFork(options.allowVfork, wrapper);
|
||
if (pid == -1) throw SysError("unable to fork");
|
||
|
||
return pid;
|
||
}
|
||
|
||
|
||
std::vector<char *> stringsToCharPtrs(const Strings & ss)
|
||
{
|
||
std::vector<char *> res;
|
||
for (auto & s : ss) res.push_back((char *) s.c_str());
|
||
res.push_back(0);
|
||
return res;
|
||
}
|
||
|
||
|
||
string runProgram(Path program, bool searchPath, const Strings & args,
|
||
const std::experimental::optional<std::string> & input)
|
||
{
|
||
checkInterrupt();
|
||
|
||
/* Create a pipe. */
|
||
Pipe out, in;
|
||
out.create();
|
||
if (input) in.create();
|
||
|
||
/* Fork. */
|
||
Pid pid = startProcess([&]() {
|
||
if (dup2(out.writeSide.get(), STDOUT_FILENO) == -1)
|
||
throw SysError("dupping stdout");
|
||
if (input && dup2(in.readSide.get(), STDIN_FILENO) == -1)
|
||
throw SysError("dupping stdin");
|
||
|
||
Strings args_(args);
|
||
args_.push_front(program);
|
||
|
||
restoreSignals();
|
||
|
||
if (searchPath)
|
||
execvp(program.c_str(), stringsToCharPtrs(args_).data());
|
||
else
|
||
execv(program.c_str(), stringsToCharPtrs(args_).data());
|
||
|
||
throw SysError(format("executing ‘%1%’") % program);
|
||
});
|
||
|
||
out.writeSide = -1;
|
||
|
||
std::thread writerThread;
|
||
|
||
std::promise<void> promise;
|
||
|
||
Finally doJoin([&]() {
|
||
if (writerThread.joinable())
|
||
writerThread.join();
|
||
});
|
||
|
||
|
||
if (input) {
|
||
in.readSide = -1;
|
||
writerThread = std::thread([&]() {
|
||
try {
|
||
writeFull(in.writeSide.get(), *input);
|
||
promise.set_value();
|
||
} catch (...) {
|
||
promise.set_exception(std::current_exception());
|
||
}
|
||
in.writeSide = -1;
|
||
});
|
||
}
|
||
|
||
string result = drainFD(out.readSide.get());
|
||
|
||
/* Wait for the child to finish. */
|
||
int status = pid.wait();
|
||
if (!statusOk(status))
|
||
throw ExecError(status, format("program ‘%1%’ %2%")
|
||
% program % statusToString(status));
|
||
|
||
/* Wait for the writer thread to finish. */
|
||
if (input) promise.get_future().get();
|
||
|
||
return result;
|
||
}
|
||
|
||
|
||
void closeMostFDs(const set<int> & exceptions)
|
||
{
|
||
int maxFD = 0;
|
||
maxFD = sysconf(_SC_OPEN_MAX);
|
||
for (int fd = 0; fd < maxFD; ++fd)
|
||
if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO
|
||
&& exceptions.find(fd) == exceptions.end())
|
||
close(fd); /* ignore result */
|
||
}
|
||
|
||
|
||
void closeOnExec(int fd)
|
||
{
|
||
int prev;
|
||
if ((prev = fcntl(fd, F_GETFD, 0)) == -1 ||
|
||
fcntl(fd, F_SETFD, prev | FD_CLOEXEC) == -1)
|
||
throw SysError("setting close-on-exec flag");
|
||
}
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
bool _isInterrupted = false;
|
||
|
||
static thread_local bool interruptThrown = false;
|
||
|
||
void setInterruptThrown()
|
||
{
|
||
interruptThrown = true;
|
||
}
|
||
|
||
void _interrupted()
|
||
{
|
||
/* Block user interrupts while an exception is being handled.
|
||
Throwing an exception while another exception is being handled
|
||
kills the program! */
|
||
if (!interruptThrown && !std::uncaught_exception()) {
|
||
interruptThrown = true;
|
||
throw Interrupted("interrupted by the user");
|
||
}
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
template<class C> C tokenizeString(const string & s, const string & separators)
|
||
{
|
||
C result;
|
||
string::size_type pos = s.find_first_not_of(separators, 0);
|
||
while (pos != string::npos) {
|
||
string::size_type end = s.find_first_of(separators, pos + 1);
|
||
if (end == string::npos) end = s.size();
|
||
string token(s, pos, end - pos);
|
||
result.insert(result.end(), token);
|
||
pos = s.find_first_not_of(separators, end);
|
||
}
|
||
return result;
|
||
}
|
||
|
||
template Strings tokenizeString(const string & s, const string & separators);
|
||
template StringSet tokenizeString(const string & s, const string & separators);
|
||
template vector<string> tokenizeString(const string & s, const string & separators);
|
||
|
||
|
||
string concatStringsSep(const string & sep, const Strings & ss)
|
||
{
|
||
string s;
|
||
for (auto & i : ss) {
|
||
if (s.size() != 0) s += sep;
|
||
s += i;
|
||
}
|
||
return s;
|
||
}
|
||
|
||
|
||
string concatStringsSep(const string & sep, const StringSet & ss)
|
||
{
|
||
string s;
|
||
for (auto & i : ss) {
|
||
if (s.size() != 0) s += sep;
|
||
s += i;
|
||
}
|
||
return s;
|
||
}
|
||
|
||
|
||
string chomp(const string & s)
|
||
{
|
||
size_t i = s.find_last_not_of(" \n\r\t");
|
||
return i == string::npos ? "" : string(s, 0, i + 1);
|
||
}
|
||
|
||
|
||
string trim(const string & s, const string & whitespace)
|
||
{
|
||
auto i = s.find_first_not_of(whitespace);
|
||
if (i == string::npos) return "";
|
||
auto j = s.find_last_not_of(whitespace);
|
||
return string(s, i, j == string::npos ? j : j - i + 1);
|
||
}
|
||
|
||
|
||
string replaceStrings(const std::string & s,
|
||
const std::string & from, const std::string & to)
|
||
{
|
||
if (from.empty()) return s;
|
||
string res = s;
|
||
size_t pos = 0;
|
||
while ((pos = res.find(from, pos)) != std::string::npos) {
|
||
res.replace(pos, from.size(), to);
|
||
pos += to.size();
|
||
}
|
||
return res;
|
||
}
|
||
|
||
|
||
string statusToString(int status)
|
||
{
|
||
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
|
||
if (WIFEXITED(status))
|
||
return (format("failed with exit code %1%") % WEXITSTATUS(status)).str();
|
||
else if (WIFSIGNALED(status)) {
|
||
int sig = WTERMSIG(status);
|
||
#if HAVE_STRSIGNAL
|
||
const char * description = strsignal(sig);
|
||
return (format("failed due to signal %1% (%2%)") % sig % description).str();
|
||
#else
|
||
return (format("failed due to signal %1%") % sig).str();
|
||
#endif
|
||
}
|
||
else
|
||
return "died abnormally";
|
||
} else return "succeeded";
|
||
}
|
||
|
||
|
||
bool statusOk(int status)
|
||
{
|
||
return WIFEXITED(status) && WEXITSTATUS(status) == 0;
|
||
}
|
||
|
||
|
||
bool hasPrefix(const string & s, const string & prefix)
|
||
{
|
||
return s.compare(0, prefix.size(), prefix) == 0;
|
||
}
|
||
|
||
|
||
bool hasSuffix(const string & s, const string & suffix)
|
||
{
|
||
return s.size() >= suffix.size() && string(s, s.size() - suffix.size()) == suffix;
|
||
}
|
||
|
||
|
||
std::string toLower(const std::string & s)
|
||
{
|
||
std::string r(s);
|
||
for (auto & c : r)
|
||
c = std::tolower(c);
|
||
return r;
|
||
}
|
||
|
||
|
||
string decodeOctalEscaped(const string & s)
|
||
{
|
||
string r;
|
||
for (string::const_iterator i = s.begin(); i != s.end(); ) {
|
||
if (*i != '\\') { r += *i++; continue; }
|
||
unsigned char c = 0;
|
||
++i;
|
||
while (i != s.end() && *i >= '0' && *i < '8')
|
||
c = c * 8 + (*i++ - '0');
|
||
r += c;
|
||
}
|
||
return r;
|
||
}
|
||
|
||
|
||
void ignoreException()
|
||
{
|
||
try {
|
||
throw;
|
||
} catch (std::exception & e) {
|
||
printError(format("error (ignored): %1%") % e.what());
|
||
}
|
||
}
|
||
|
||
|
||
string filterANSIEscapes(const string & s, bool nixOnly)
|
||
{
|
||
string t, r;
|
||
enum { stTop, stEscape, stCSI } state = stTop;
|
||
for (auto c : s) {
|
||
if (state == stTop) {
|
||
if (c == '\e') {
|
||
state = stEscape;
|
||
r = c;
|
||
} else
|
||
t += c;
|
||
} else if (state == stEscape) {
|
||
r += c;
|
||
if (c == '[')
|
||
state = stCSI;
|
||
else {
|
||
t += r;
|
||
state = stTop;
|
||
}
|
||
} else {
|
||
r += c;
|
||
if (c >= 0x40 && c != 0x7e) {
|
||
if (nixOnly && (c != 'p' && c != 'q' && c != 's' && c != 'a' && c != 'b'))
|
||
t += r;
|
||
state = stTop;
|
||
r.clear();
|
||
}
|
||
}
|
||
}
|
||
t += r;
|
||
return t;
|
||
}
|
||
|
||
|
||
static char base64Chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
|
||
|
||
|
||
string base64Encode(const string & s)
|
||
{
|
||
string res;
|
||
int data = 0, nbits = 0;
|
||
|
||
for (char c : s) {
|
||
data = data << 8 | (unsigned char) c;
|
||
nbits += 8;
|
||
while (nbits >= 6) {
|
||
nbits -= 6;
|
||
res.push_back(base64Chars[data >> nbits & 0x3f]);
|
||
}
|
||
}
|
||
|
||
if (nbits) res.push_back(base64Chars[data << (6 - nbits) & 0x3f]);
|
||
while (res.size() % 4) res.push_back('=');
|
||
|
||
return res;
|
||
}
|
||
|
||
|
||
string base64Decode(const string & s)
|
||
{
|
||
bool init = false;
|
||
char decode[256];
|
||
if (!init) {
|
||
// FIXME: not thread-safe.
|
||
memset(decode, -1, sizeof(decode));
|
||
for (int i = 0; i < 64; i++)
|
||
decode[(int) base64Chars[i]] = i;
|
||
init = true;
|
||
}
|
||
|
||
string res;
|
||
unsigned int d = 0, bits = 0;
|
||
|
||
for (char c : s) {
|
||
if (c == '=') break;
|
||
if (c == '\n') continue;
|
||
|
||
char digit = decode[(unsigned char) c];
|
||
if (digit == -1)
|
||
throw Error("invalid character in Base64 string");
|
||
|
||
bits += 6;
|
||
d = d << 6 | digit;
|
||
if (bits >= 8) {
|
||
res.push_back(d >> (bits - 8) & 0xff);
|
||
bits -= 8;
|
||
}
|
||
}
|
||
|
||
return res;
|
||
}
|
||
|
||
|
||
void callFailure(const std::function<void(std::exception_ptr exc)> & failure, std::exception_ptr exc)
|
||
{
|
||
try {
|
||
failure(exc);
|
||
} catch (std::exception & e) {
|
||
printError(format("uncaught exception: %s") % e.what());
|
||
abort();
|
||
}
|
||
}
|
||
|
||
|
||
static Sync<std::list<std::function<void()>>> _interruptCallbacks;
|
||
|
||
static void signalHandlerThread(sigset_t set)
|
||
{
|
||
while (true) {
|
||
int signal = 0;
|
||
sigwait(&set, &signal);
|
||
|
||
if (signal == SIGINT || signal == SIGTERM || signal == SIGHUP)
|
||
triggerInterrupt();
|
||
}
|
||
}
|
||
|
||
void triggerInterrupt()
|
||
{
|
||
_isInterrupted = true;
|
||
|
||
{
|
||
auto interruptCallbacks(_interruptCallbacks.lock());
|
||
for (auto & callback : *interruptCallbacks) {
|
||
try {
|
||
callback();
|
||
} catch (...) {
|
||
ignoreException();
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
static sigset_t savedSignalMask;
|
||
|
||
void startSignalHandlerThread()
|
||
{
|
||
if (sigprocmask(SIG_BLOCK, nullptr, &savedSignalMask))
|
||
throw SysError("quering signal mask");
|
||
|
||
sigset_t set;
|
||
sigemptyset(&set);
|
||
sigaddset(&set, SIGINT);
|
||
sigaddset(&set, SIGTERM);
|
||
sigaddset(&set, SIGHUP);
|
||
sigaddset(&set, SIGPIPE);
|
||
if (pthread_sigmask(SIG_BLOCK, &set, nullptr))
|
||
throw SysError("blocking signals");
|
||
|
||
std::thread(signalHandlerThread, set).detach();
|
||
}
|
||
|
||
void restoreSignals()
|
||
{
|
||
if (sigprocmask(SIG_SETMASK, &savedSignalMask, nullptr))
|
||
throw SysError("restoring signals");
|
||
}
|
||
|
||
/* RAII helper to automatically deregister a callback. */
|
||
struct InterruptCallbackImpl : InterruptCallback
|
||
{
|
||
std::list<std::function<void()>>::iterator it;
|
||
~InterruptCallbackImpl() override
|
||
{
|
||
_interruptCallbacks.lock()->erase(it);
|
||
}
|
||
};
|
||
|
||
std::unique_ptr<InterruptCallback> createInterruptCallback(std::function<void()> callback)
|
||
{
|
||
auto interruptCallbacks(_interruptCallbacks.lock());
|
||
interruptCallbacks->push_back(callback);
|
||
|
||
auto res = std::make_unique<InterruptCallbackImpl>();
|
||
res->it = interruptCallbacks->end();
|
||
res->it--;
|
||
|
||
return std::unique_ptr<InterruptCallback>(res.release());
|
||
}
|
||
|
||
}
|