1231 lines
28 KiB
C++
1231 lines
28 KiB
C++
#include "config.h"
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#include "util.hh"
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#include "affinity.hh"
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#include <iostream>
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#include <cerrno>
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#include <cstdio>
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#include <cstdlib>
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#include <sstream>
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#include <cstring>
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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(const FormatOrString & fs, unsigned int status)
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: status(status)
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{
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err = fs.s;
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}
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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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SysError::SysError(const FormatOrString & fs)
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: Error(format("%1%: %2%") % fs.s % strerror(errno))
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, errNo(errno)
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{
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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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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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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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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 string(path, 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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#ifdef HAVE_STATX
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struct statx st;
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res = statx(AT_FDCWD, path.c_str(), AT_SYMLINK_NOFOLLOW, 0, &st);
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#else
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struct stat st;
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res = lstat(path.c_str(), &st);
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#endif
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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, st.st_size);
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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)) { /* 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, dirent->d_type);
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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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unsigned char * buf = new unsigned char[st.st_size];
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AutoDeleteArray<unsigned char> d(buf);
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readFull(fd, buf, st.st_size);
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return string((char *) buf, 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);
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if (fd == -1)
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throw SysError(format("opening file `%1%'") % path);
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return drain ? drainFD(fd) : readFile(fd);
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}
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void writeFile(const Path & path, const string & s)
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{
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AutoCloseFD fd = open(path.c_str(), O_WRONLY | O_TRUNC | O_CREAT, 0666);
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if (fd == -1)
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throw SysError(format("opening file '%1%'") % path);
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writeFull(fd, 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, size_t linkThreshold)
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{
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checkInterrupt();
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printMsg(lvlVomit, format("%1%") % path);
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#ifdef HAVE_STATX
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# define st_mode stx_mode
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# define st_size stx_size
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# define st_nlink stx_nlink
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struct statx st;
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if (statx(AT_FDCWD, path.c_str(),
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AT_SYMLINK_NOFOLLOW,
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STATX_SIZE | STATX_NLINK | STATX_MODE, &st) == -1)
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throw SysError(format("getting status of `%1%'") % path);
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#else
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struct stat st = lstat(path);
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#endif
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if (!S_ISDIR(st.st_mode) && st.st_nlink <= linkThreshold)
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bytesFreed += st.st_size;
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if (S_ISDIR(st.st_mode)) {
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/* Make the directory writable. */
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if (!(st.st_mode & S_IWUSR)) {
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if (chmod(path.c_str(), st.st_mode | S_IWUSR) == -1)
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throw SysError(format("making `%1%' writable") % path);
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}
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for (auto & i : readDirectory(path))
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_deletePath(path + "/" + i.name, bytesFreed, linkThreshold);
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}
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#undef st_mode
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#undef st_size
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#undef st_nlink
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if (remove(path.c_str()) == -1)
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throw SysError(format("cannot unlink `%1%'") % path);
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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, size_t linkThreshold)
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{
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startNest(nest, lvlDebug,
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format("recursively deleting path `%1%'") % path);
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bytesFreed = 0;
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_deletePath(path, bytesFreed, linkThreshold);
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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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/* 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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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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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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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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LogType logType = ltPretty;
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Verbosity verbosity = lvlInfo;
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static int nestingLevel = 0;
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Nest::Nest()
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{
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nest = false;
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}
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Nest::~Nest()
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{
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close();
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}
|
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static string escVerbosity(Verbosity level)
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{
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return std::to_string((int) level);
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}
|
||
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||
|
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void Nest::open(Verbosity level, const FormatOrString & fs)
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||
{
|
||
if (level <= verbosity) {
|
||
if (logType == ltEscapes)
|
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std::cerr << "\033[" << escVerbosity(level) << "p"
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<< fs.s << "\n";
|
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else
|
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printMsg_(level, fs);
|
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nest = true;
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nestingLevel++;
|
||
}
|
||
}
|
||
|
||
|
||
void Nest::close()
|
||
{
|
||
if (nest) {
|
||
nestingLevel--;
|
||
if (logType == ltEscapes)
|
||
std::cerr << "\033[q";
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||
nest = false;
|
||
}
|
||
}
|
||
|
||
|
||
void printMsg_(Verbosity level, const FormatOrString & fs)
|
||
{
|
||
checkInterrupt();
|
||
if (level > verbosity) return;
|
||
string prefix;
|
||
if (logType == ltPretty)
|
||
for (int i = 0; i < nestingLevel; i++)
|
||
prefix += "| ";
|
||
else if (logType == ltEscapes && level != lvlInfo)
|
||
prefix = "\033[" + escVerbosity(level) + "s";
|
||
string s = (format("%1%%2%\n") % prefix % fs.s).str();
|
||
writeToStderr(s);
|
||
}
|
||
|
||
|
||
void warnOnce(bool & haveWarned, const FormatOrString & fs)
|
||
{
|
||
if (!haveWarned) {
|
||
printMsg(lvlError, format("warning: %1%") % fs.s);
|
||
haveWarned = true;
|
||
}
|
||
}
|
||
|
||
|
||
void writeToStderr(const string & s)
|
||
{
|
||
try {
|
||
if (_writeToStderr)
|
||
_writeToStderr((const unsigned char *) s.data(), s.size());
|
||
else
|
||
writeFull(STDERR_FILENO, s);
|
||
} catch (SysError & e) {
|
||
/* Ignore failing writes to stderr if we're in an exception
|
||
handler, otherwise throw an exception. We need to ignore
|
||
write errors in exception handlers to ensure that cleanup
|
||
code runs to completion if the other side of stderr has
|
||
been closed unexpectedly. */
|
||
if (!std::uncaught_exception()) throw;
|
||
}
|
||
}
|
||
|
||
|
||
void (*_writeToStderr) (const unsigned char * buf, size_t count) = 0;
|
||
|
||
|
||
void readFull(int fd, unsigned char * buf, size_t count)
|
||
{
|
||
while (count) {
|
||
checkInterrupt();
|
||
ssize_t res = read(fd, (char *) buf, count);
|
||
if (res == -1) {
|
||
if (errno == EINTR) continue;
|
||
throw SysError("reading from file");
|
||
}
|
||
if (res == 0) throw EndOfFile("unexpected end-of-file");
|
||
count -= res;
|
||
buf += res;
|
||
}
|
||
}
|
||
|
||
|
||
void writeFull(int fd, const unsigned char * buf, size_t count)
|
||
{
|
||
while (count) {
|
||
checkInterrupt();
|
||
ssize_t res = write(fd, (char *) buf, count);
|
||
if (res == -1) {
|
||
if (errno == EINTR) continue;
|
||
throw SysError("writing to file");
|
||
}
|
||
count -= res;
|
||
buf += res;
|
||
}
|
||
}
|
||
|
||
|
||
void writeFull(int fd, const string & s)
|
||
{
|
||
writeFull(fd, (const unsigned char *) s.data(), s.size());
|
||
}
|
||
|
||
|
||
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(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;
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
AutoCloseFD::AutoCloseFD()
|
||
{
|
||
fd = -1;
|
||
}
|
||
|
||
|
||
AutoCloseFD::AutoCloseFD(int fd)
|
||
{
|
||
this->fd = fd;
|
||
}
|
||
|
||
|
||
AutoCloseFD::AutoCloseFD(const AutoCloseFD & fd)
|
||
{
|
||
/* Copying an AutoCloseFD isn't allowed (who should get to close
|
||
it?). But as an edge case, allow copying of closed
|
||
AutoCloseFDs. This is necessary due to tiresome reasons
|
||
involving copy constructor use on default object values in STL
|
||
containers (like when you do `map[value]' where value isn't in
|
||
the map yet). */
|
||
this->fd = fd.fd;
|
||
if (this->fd != -1) abort();
|
||
}
|
||
|
||
|
||
AutoCloseFD::~AutoCloseFD()
|
||
{
|
||
try {
|
||
close();
|
||
} catch (...) {
|
||
ignoreException();
|
||
}
|
||
}
|
||
|
||
|
||
void AutoCloseFD::operator =(int fd)
|
||
{
|
||
if (this->fd != fd) close();
|
||
this->fd = fd;
|
||
}
|
||
|
||
|
||
AutoCloseFD::operator int() 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);
|
||
fd = -1;
|
||
}
|
||
}
|
||
|
||
|
||
bool AutoCloseFD::isOpen()
|
||
{
|
||
return fd != -1;
|
||
}
|
||
|
||
|
||
/* Pass responsibility for closing this fd to the caller. */
|
||
int AutoCloseFD::borrow()
|
||
{
|
||
int oldFD = fd;
|
||
fd = -1;
|
||
return oldFD;
|
||
}
|
||
|
||
|
||
void Pipe::create()
|
||
{
|
||
int fds[2];
|
||
if (pipe(fds) != 0) throw SysError("creating pipe");
|
||
readSide = fds[0];
|
||
writeSide = fds[1];
|
||
closeOnExec(readSide);
|
||
closeOnExec(writeSide);
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
AutoCloseDir::AutoCloseDir()
|
||
{
|
||
dir = 0;
|
||
}
|
||
|
||
|
||
AutoCloseDir::AutoCloseDir(DIR * dir)
|
||
{
|
||
this->dir = dir;
|
||
}
|
||
|
||
|
||
AutoCloseDir::~AutoCloseDir()
|
||
{
|
||
close();
|
||
}
|
||
|
||
|
||
void AutoCloseDir::operator =(DIR * dir)
|
||
{
|
||
this->dir = dir;
|
||
}
|
||
|
||
|
||
AutoCloseDir::operator DIR *()
|
||
{
|
||
return dir;
|
||
}
|
||
|
||
|
||
void AutoCloseDir::close()
|
||
{
|
||
if (dir) {
|
||
closedir(dir);
|
||
dir = 0;
|
||
}
|
||
}
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
Pid::Pid()
|
||
: pid(-1), separatePG(false), killSignal(SIGKILL)
|
||
{
|
||
}
|
||
|
||
|
||
Pid::Pid(pid_t pid)
|
||
: pid(pid), separatePG(false), killSignal(SIGKILL)
|
||
{
|
||
}
|
||
|
||
|
||
Pid::~Pid()
|
||
{
|
||
kill();
|
||
}
|
||
|
||
|
||
void Pid::operator =(pid_t pid)
|
||
{
|
||
if (this->pid != pid) kill();
|
||
this->pid = pid;
|
||
killSignal = SIGKILL; // reset signal to default
|
||
}
|
||
|
||
|
||
Pid::operator pid_t()
|
||
{
|
||
return pid;
|
||
}
|
||
|
||
|
||
void Pid::kill(bool quiet)
|
||
{
|
||
if (pid == -1 || pid == 0) return;
|
||
|
||
if (!quiet)
|
||
printMsg(lvlError, 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)
|
||
printMsg(lvlError, (SysError(format("killing process %1%") % pid).msg()));
|
||
|
||
/* Wait until the child dies, disregarding the exit status. */
|
||
int status;
|
||
while (waitpid(pid, &status, 0) == -1) {
|
||
checkInterrupt();
|
||
if (errno != EINTR) {
|
||
printMsg(lvlError,
|
||
(SysError(format("waiting for process %1%") % pid).msg()));
|
||
break;
|
||
}
|
||
}
|
||
|
||
pid = -1;
|
||
}
|
||
|
||
|
||
int Pid::wait(bool block)
|
||
{
|
||
assert(pid != -1);
|
||
while (1) {
|
||
int status;
|
||
int res = waitpid(pid, &status, block ? 0 : WNOHANG);
|
||
if (res == pid) {
|
||
pid = -1;
|
||
return status;
|
||
}
|
||
if (res == 0 && !block) return -1;
|
||
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;
|
||
}
|
||
|
||
|
||
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. */
|
||
|
||
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;
|
||
#elif __GNU__
|
||
/* Killing all a user's processes using PID=-1 does currently
|
||
not work on the Hurd. */
|
||
if (kill(getpid(), SIGKILL) == 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);
|
||
});
|
||
|
||
int status = pid.wait(true);
|
||
#if __GNU__
|
||
/* When the child killed itself, status = SIGKILL. */
|
||
if (status == SIGKILL) return;
|
||
#endif
|
||
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'. */
|
||
}
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
pid_t startProcess(std::function<void()> fun,
|
||
bool dieWithParent, const string & errorPrefix, bool runExitHandlers)
|
||
{
|
||
pid_t pid = fork();
|
||
if (pid == -1) throw SysError("unable to fork");
|
||
|
||
if (pid == 0) {
|
||
_writeToStderr = 0;
|
||
try {
|
||
#if __linux__
|
||
if (dieWithParent && prctl(PR_SET_PDEATHSIG, SIGKILL) == -1)
|
||
throw SysError("setting death signal");
|
||
#endif
|
||
restoreAffinity();
|
||
fun();
|
||
} catch (std::exception & e) {
|
||
try {
|
||
std::cerr << errorPrefix << e.what() << "\n";
|
||
} catch (...) { }
|
||
} catch (...) { }
|
||
if (runExitHandlers)
|
||
exit(1);
|
||
else
|
||
_exit(1);
|
||
}
|
||
|
||
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)
|
||
{
|
||
checkInterrupt();
|
||
|
||
/* Create a pipe. */
|
||
Pipe pipe;
|
||
pipe.create();
|
||
|
||
/* Fork. */
|
||
Pid pid = startProcess([&]() {
|
||
if (dup2(pipe.writeSide, STDOUT_FILENO) == -1)
|
||
throw SysError("dupping stdout");
|
||
|
||
Strings args_(args);
|
||
args_.push_front(program);
|
||
|
||
if (searchPath)
|
||
execvp(program.c_str(), stringsToCharPtrs(args_).data());
|
||
else
|
||
execv(program.c_str(), stringsToCharPtrs(args_).data());
|
||
|
||
throw SysError(format("executing `%1%'") % program);
|
||
});
|
||
|
||
pipe.writeSide.close();
|
||
|
||
string result = drainFD(pipe.readSide);
|
||
|
||
/* Wait for the child to finish. */
|
||
int status = pid.wait(true);
|
||
if (!statusOk(status))
|
||
throw ExecError(format("program `%1%' %2%")
|
||
% program % statusToString(status));
|
||
|
||
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");
|
||
}
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
volatile sig_atomic_t _isInterrupted = 0;
|
||
|
||
void _interrupted()
|
||
{
|
||
/* Block user interrupts while an exception is being handled.
|
||
Throwing an exception while another exception is being handled
|
||
kills the program! */
|
||
if (!std::uncaught_exception()) {
|
||
_isInterrupted = 0;
|
||
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;
|
||
foreach (Strings::const_iterator, i, ss) {
|
||
if (s.size() != 0) s += sep;
|
||
s += *i;
|
||
}
|
||
return s;
|
||
}
|
||
|
||
|
||
string concatStringsSep(const string & sep, const StringSet & ss)
|
||
{
|
||
string s;
|
||
foreach (StringSet::const_iterator, 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 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 hasSuffix(const string & s, const string & suffix)
|
||
{
|
||
return s.size() >= suffix.size() && string(s, s.size() - suffix.size()) == suffix;
|
||
}
|
||
|
||
|
||
void expect(std::istream & str, const string & s)
|
||
{
|
||
char s2[s.size()];
|
||
str.read(s2, s.size());
|
||
if (string(s2, s.size()) != s)
|
||
throw FormatError(format("expected string `%1%'") % s);
|
||
}
|
||
|
||
|
||
string parseString(std::istream & str)
|
||
{
|
||
string res;
|
||
expect(str, "\"");
|
||
int c;
|
||
while ((c = str.get()) != '"')
|
||
if (c == '\\') {
|
||
c = str.get();
|
||
if (c == 'n') res += '\n';
|
||
else if (c == 'r') res += '\r';
|
||
else if (c == 't') res += '\t';
|
||
else res += c;
|
||
}
|
||
else res += c;
|
||
return res;
|
||
}
|
||
|
||
|
||
bool endOfList(std::istream & str)
|
||
{
|
||
if (str.peek() == ',') {
|
||
str.get();
|
||
return false;
|
||
}
|
||
if (str.peek() == ']') {
|
||
str.get();
|
||
return true;
|
||
}
|
||
return false;
|
||
}
|
||
|
||
|
||
void ignoreException()
|
||
{
|
||
try {
|
||
throw;
|
||
} catch (std::exception & e) {
|
||
printMsg(lvlError, format("error (ignored): %1%") % e.what());
|
||
}
|
||
}
|
||
|
||
static const string pathNullDevice = "/dev/null";
|
||
|
||
/* Common initialisation performed in child processes. */
|
||
void commonChildInit(Pipe & logPipe)
|
||
{
|
||
/* Put the child in a separate session (and thus a separate
|
||
process group) so that it has no controlling terminal (meaning
|
||
that e.g. ssh cannot open /dev/tty) and it doesn't receive
|
||
terminal signals. */
|
||
if (setsid() == -1)
|
||
throw SysError(format("creating a new session"));
|
||
|
||
/* Dup the write side of the logger pipe into stderr. */
|
||
if (dup2(logPipe.writeSide, STDERR_FILENO) == -1)
|
||
throw SysError("cannot pipe standard error into log file");
|
||
|
||
/* Dup stderr to stdout. */
|
||
if (dup2(STDERR_FILENO, STDOUT_FILENO) == -1)
|
||
throw SysError("cannot dup stderr into stdout");
|
||
|
||
/* Reroute stdin to /dev/null. */
|
||
int fdDevNull = open(pathNullDevice.c_str(), O_RDWR);
|
||
if (fdDevNull == -1)
|
||
throw SysError(format("cannot open `%1%'") % pathNullDevice);
|
||
if (dup2(fdDevNull, STDIN_FILENO) == -1)
|
||
throw SysError("cannot dup null device into stdin");
|
||
close(fdDevNull);
|
||
}
|
||
|
||
//////////////////////////////////////////////////////////////////////
|
||
|
||
Agent::Agent(const string &command, const Strings &args)
|
||
{
|
||
debug(format("starting agent '%1%'") % command);
|
||
|
||
/* Create a pipe to get the output of the child. */
|
||
fromAgent.create();
|
||
|
||
/* Create the communication pipes. */
|
||
toAgent.create();
|
||
|
||
/* Create a pipe to get the output of the builder. */
|
||
builderOut.create();
|
||
|
||
/* Fork the hook. */
|
||
pid = startProcess([&]() {
|
||
|
||
commonChildInit(fromAgent);
|
||
|
||
if (chdir("/") == -1) throw SysError("changing into `/");
|
||
|
||
/* Dup the communication pipes. */
|
||
if (dup2(toAgent.readSide, STDIN_FILENO) == -1)
|
||
throw SysError("dupping to-hook read side");
|
||
|
||
/* Use fd 4 for the builder's stdout/stderr. */
|
||
if (dup2(builderOut.writeSide, 4) == -1)
|
||
throw SysError("dupping builder's stdout/stderr");
|
||
|
||
Strings allArgs;
|
||
allArgs.push_back(command);
|
||
allArgs.insert(allArgs.end(), args.begin(), args.end()); // append
|
||
|
||
execv(command.c_str(), stringsToCharPtrs(allArgs).data());
|
||
|
||
throw SysError(format("executing `%1%'") % command);
|
||
});
|
||
|
||
pid.setSeparatePG(true);
|
||
fromAgent.writeSide.close();
|
||
toAgent.readSide.close();
|
||
}
|
||
|
||
|
||
Agent::~Agent()
|
||
{
|
||
try {
|
||
toAgent.writeSide.close();
|
||
pid.kill(true);
|
||
} catch (...) {
|
||
ignoreException();
|
||
}
|
||
}
|
||
|
||
|
||
}
|