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-rw-r--r--nix/libutil/util.cc1105
1 files changed, 1105 insertions, 0 deletions
diff --git a/nix/libutil/util.cc b/nix/libutil/util.cc
new file mode 100644
index 0000000000..15c462ce4e
--- /dev/null
+++ b/nix/libutil/util.cc
@@ -0,0 +1,1105 @@
+#include "config.h"
+
+#include <iostream>
+#include <cerrno>
+#include <cstdio>
+#include <cstdlib>
+#include <sstream>
+#include <cstring>
+
+#include <sys/wait.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <limits.h>
+
+#ifdef __APPLE__
+#include <sys/syscall.h>
+#endif
+
+#include "util.hh"
+
+
+extern char * * environ;
+
+
+namespace nix {
+
+
+BaseError::BaseError(const FormatOrString & fs, unsigned int status)
+ : status(status)
+{
+ err = fs.s;
+}
+
+
+BaseError & BaseError::addPrefix(const FormatOrString & fs)
+{
+ prefix_ = fs.s + prefix_;
+ return *this;
+}
+
+
+SysError::SysError(const FormatOrString & fs)
+ : Error(format("%1%: %2%") % fs.s % strerror(errno))
+ , errNo(errno)
+{
+}
+
+
+string getEnv(const string & key, const string & def)
+{
+ char * value = getenv(key.c_str());
+ return value ? string(value) : def;
+}
+
+
+Path absPath(Path path, Path dir)
+{
+ if (path[0] != '/') {
+ if (dir == "") {
+#ifdef __GNU__
+ /* GNU (aka. GNU/Hurd) doesn't have any limitation on path
+ lengths and doesn't define `PATH_MAX'. */
+ char *buf = getcwd(NULL, 0);
+ if (buf == NULL)
+#else
+ char buf[PATH_MAX];
+ if (!getcwd(buf, sizeof(buf)))
+#endif
+ throw SysError("cannot get cwd");
+ dir = buf;
+#ifdef __GNU__
+ free(buf);
+#endif
+ }
+ path = dir + "/" + path;
+ }
+ return canonPath(path);
+}
+
+
+Path canonPath(const Path & path, bool resolveSymlinks)
+{
+ string s;
+
+ if (path[0] != '/')
+ throw Error(format("not an absolute path: `%1%'") % path);
+
+ string::const_iterator i = path.begin(), end = path.end();
+ string temp;
+
+ /* Count the number of times we follow a symlink and stop at some
+ arbitrary (but high) limit to prevent infinite loops. */
+ unsigned int followCount = 0, maxFollow = 1024;
+
+ while (1) {
+
+ /* Skip slashes. */
+ while (i != end && *i == '/') i++;
+ if (i == end) break;
+
+ /* Ignore `.'. */
+ if (*i == '.' && (i + 1 == end || i[1] == '/'))
+ i++;
+
+ /* If `..', delete the last component. */
+ else if (*i == '.' && i + 1 < end && i[1] == '.' &&
+ (i + 2 == end || i[2] == '/'))
+ {
+ if (!s.empty()) s.erase(s.rfind('/'));
+ i += 2;
+ }
+
+ /* Normal component; copy it. */
+ else {
+ s += '/';
+ while (i != end && *i != '/') s += *i++;
+
+ /* If s points to a symlink, resolve it and restart (since
+ the symlink target might contain new symlinks). */
+ if (resolveSymlinks && isLink(s)) {
+ if (++followCount >= maxFollow)
+ throw Error(format("infinite symlink recursion in path `%1%'") % path);
+ temp = absPath(readLink(s), dirOf(s))
+ + string(i, end);
+ i = temp.begin(); /* restart */
+ end = temp.end();
+ s = "";
+ /* !!! potential for infinite loop */
+ }
+ }
+ }
+
+ return s.empty() ? "/" : s;
+}
+
+
+Path dirOf(const Path & path)
+{
+ Path::size_type pos = path.rfind('/');
+ if (pos == string::npos)
+ throw Error(format("invalid file name `%1%'") % path);
+ return pos == 0 ? "/" : Path(path, 0, pos);
+}
+
+
+string baseNameOf(const Path & path)
+{
+ Path::size_type pos = path.rfind('/');
+ if (pos == string::npos)
+ throw Error(format("invalid file name `%1%'") % path);
+ return string(path, pos + 1);
+}
+
+
+bool isInDir(const Path & path, const Path & dir)
+{
+ return path[0] == '/'
+ && string(path, 0, dir.size()) == dir
+ && path.size() >= dir.size() + 2
+ && path[dir.size()] == '/';
+}
+
+
+struct stat lstat(const Path & path)
+{
+ struct stat st;
+ if (lstat(path.c_str(), &st))
+ throw SysError(format("getting status of `%1%'") % path);
+ return st;
+}
+
+
+bool pathExists(const Path & path)
+{
+ int res;
+ struct stat st;
+ res = lstat(path.c_str(), &st);
+ if (!res) return true;
+ if (errno != ENOENT && errno != ENOTDIR)
+ throw SysError(format("getting status of %1%") % path);
+ return false;
+}
+
+
+Path readLink(const Path & path)
+{
+ checkInterrupt();
+ struct stat st = lstat(path);
+ if (!S_ISLNK(st.st_mode))
+ throw Error(format("`%1%' is not a symlink") % path);
+ char buf[st.st_size];
+ if (readlink(path.c_str(), buf, st.st_size) != st.st_size)
+ throw SysError(format("reading symbolic link `%1%'") % path);
+ return string(buf, st.st_size);
+}
+
+
+bool isLink(const Path & path)
+{
+ struct stat st = lstat(path);
+ return S_ISLNK(st.st_mode);
+}
+
+
+Strings readDirectory(const Path & path)
+{
+ Strings names;
+
+ AutoCloseDir dir = opendir(path.c_str());
+ if (!dir) throw SysError(format("opening directory `%1%'") % path);
+
+ struct dirent * dirent;
+ while (errno = 0, dirent = readdir(dir)) { /* sic */
+ checkInterrupt();
+ string name = dirent->d_name;
+ if (name == "." || name == "..") continue;
+ names.push_back(name);
+ }
+ if (errno) throw SysError(format("reading directory `%1%'") % path);
+
+ return names;
+}
+
+
+string readFile(int fd)
+{
+ struct stat st;
+ if (fstat(fd, &st) == -1)
+ throw SysError("statting file");
+
+ unsigned char * buf = new unsigned char[st.st_size];
+ AutoDeleteArray<unsigned char> d(buf);
+ readFull(fd, buf, st.st_size);
+
+ return string((char *) buf, st.st_size);
+}
+
+
+string readFile(const Path & path, bool drain)
+{
+ AutoCloseFD fd = open(path.c_str(), O_RDONLY);
+ if (fd == -1)
+ throw SysError(format("opening file `%1%'") % path);
+ return drain ? drainFD(fd) : readFile(fd);
+}
+
+
+void writeFile(const Path & path, const string & s)
+{
+ AutoCloseFD fd = open(path.c_str(), O_WRONLY | O_TRUNC | O_CREAT, 0666);
+ if (fd == -1)
+ throw SysError(format("opening file `%1%'") % path);
+ writeFull(fd, (unsigned char *) s.data(), s.size());
+}
+
+
+string readLine(int fd)
+{
+ string s;
+ while (1) {
+ checkInterrupt();
+ char ch;
+ ssize_t rd = read(fd, &ch, 1);
+ if (rd == -1) {
+ if (errno != EINTR)
+ throw SysError("reading a line");
+ } else if (rd == 0)
+ throw EndOfFile("unexpected EOF reading a line");
+ else {
+ if (ch == '\n') return s;
+ s += ch;
+ }
+ }
+}
+
+
+void writeLine(int fd, string s)
+{
+ s += '\n';
+ writeFull(fd, (const unsigned char *) s.data(), s.size());
+}
+
+
+static void _deletePath(const Path & path, unsigned long long & bytesFreed)
+{
+ checkInterrupt();
+
+ printMsg(lvlVomit, format("%1%") % path);
+
+ struct stat st = lstat(path);
+
+ if (!S_ISDIR(st.st_mode) && st.st_nlink == 1)
+ bytesFreed += st.st_blocks * 512;
+
+ if (S_ISDIR(st.st_mode)) {
+ Strings names = readDirectory(path);
+
+ /* Make the directory writable. */
+ if (!(st.st_mode & S_IWUSR)) {
+ if (chmod(path.c_str(), st.st_mode | S_IWUSR) == -1)
+ throw SysError(format("making `%1%' writable") % path);
+ }
+
+ for (Strings::iterator i = names.begin(); i != names.end(); ++i)
+ _deletePath(path + "/" + *i, bytesFreed);
+ }
+
+ if (remove(path.c_str()) == -1)
+ throw SysError(format("cannot unlink `%1%'") % path);
+}
+
+
+void deletePath(const Path & path)
+{
+ unsigned long long dummy;
+ deletePath(path, dummy);
+}
+
+
+void deletePath(const Path & path, unsigned long long & bytesFreed)
+{
+ startNest(nest, lvlDebug,
+ format("recursively deleting path `%1%'") % path);
+ bytesFreed = 0;
+ _deletePath(path, bytesFreed);
+}
+
+
+static Path tempName(Path tmpRoot, const Path & prefix, bool includePid,
+ int & counter)
+{
+ tmpRoot = canonPath(tmpRoot.empty() ? getEnv("TMPDIR", "/tmp") : tmpRoot, true);
+ if (includePid)
+ return (format("%1%/%2%-%3%-%4%") % tmpRoot % prefix % getpid() % counter++).str();
+ else
+ return (format("%1%/%2%-%3%") % tmpRoot % prefix % counter++).str();
+}
+
+
+Path createTempDir(const Path & tmpRoot, const Path & prefix,
+ bool includePid, bool useGlobalCounter, mode_t mode)
+{
+ static int globalCounter = 0;
+ int localCounter = 0;
+ int & counter(useGlobalCounter ? globalCounter : localCounter);
+
+ while (1) {
+ checkInterrupt();
+ Path tmpDir = tempName(tmpRoot, prefix, includePid, counter);
+ if (mkdir(tmpDir.c_str(), mode) == 0) {
+ /* Explicitly set the group of the directory. This is to
+ work around around problems caused by BSD's group
+ ownership semantics (directories inherit the group of
+ the parent). For instance, the group of /tmp on
+ FreeBSD is "wheel", so all directories created in /tmp
+ will be owned by "wheel"; but if the user is not in
+ "wheel", then "tar" will fail to unpack archives that
+ have the setgid bit set on directories. */
+ if (chown(tmpDir.c_str(), (uid_t) -1, getegid()) != 0)
+ throw SysError(format("setting group of directory `%1%'") % tmpDir);
+ return tmpDir;
+ }
+ if (errno != EEXIST)
+ throw SysError(format("creating directory `%1%'") % tmpDir);
+ }
+}
+
+
+Paths createDirs(const Path & path)
+{
+ Paths created;
+ if (path == "/") return created;
+
+ struct stat st;
+ if (lstat(path.c_str(), &st) == -1) {
+ created = createDirs(dirOf(path));
+ if (mkdir(path.c_str(), 0777) == -1 && errno != EEXIST)
+ throw SysError(format("creating directory `%1%'") % path);
+ st = lstat(path);
+ created.push_back(path);
+ }
+
+ if (!S_ISDIR(st.st_mode)) throw Error(format("`%1%' is not a directory") % path);
+
+ return created;
+}
+
+
+void createSymlink(const Path & target, const Path & link)
+{
+ if (symlink(target.c_str(), link.c_str()))
+ throw SysError(format("creating symlink from `%1%' to `%2%'") % link % target);
+}
+
+
+LogType logType = ltPretty;
+Verbosity verbosity = lvlInfo;
+
+static int nestingLevel = 0;
+
+
+Nest::Nest()
+{
+ nest = false;
+}
+
+
+Nest::~Nest()
+{
+ close();
+}
+
+
+static string escVerbosity(Verbosity level)
+{
+ return int2String((int) level);
+}
+
+
+void Nest::open(Verbosity level, const FormatOrString & fs)
+{
+ if (level <= verbosity) {
+ if (logType == ltEscapes)
+ std::cerr << "\033[" << escVerbosity(level) << "p"
+ << fs.s << "\n";
+ else
+ printMsg_(level, fs);
+ nest = true;
+ nestingLevel++;
+ }
+}
+
+
+void Nest::close()
+{
+ if (nest) {
+ nestingLevel--;
+ if (logType == ltEscapes)
+ std::cerr << "\033[q";
+ 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 {
+ _writeToStderr((const unsigned char *) s.data(), s.size());
+ } 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;
+ }
+}
+
+
+static void defaultWriteToStderr(const unsigned char * buf, size_t count)
+{
+ writeFull(STDERR_FILENO, buf, count);
+}
+
+
+void (*_writeToStderr) (const unsigned char * buf, size_t count) = defaultWriteToStderr;
+
+
+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;
+ }
+}
+
+
+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()
+{
+ 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()
+{
+ if (pid == -1 || pid == 0) return;
+
+ 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;
+ pid = fork();
+ switch (pid) {
+
+ case -1:
+ throw SysError("unable to fork");
+
+ case 0:
+ try { /* child */
+
+ 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);
+ }
+
+ } catch (std::exception & e) {
+ writeToStderr((format("killing processes belonging to uid `%1%': %2%\n") % uid % e.what()).str());
+ _exit(1);
+ }
+ _exit(0);
+ }
+
+ /* parent */
+ int status = pid.wait(true);
+ 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'. */
+}
+
+
+//////////////////////////////////////////////////////////////////////
+
+
+string runProgram(Path program, bool searchPath, const Strings & args)
+{
+ checkInterrupt();
+
+ std::vector<const char *> cargs; /* careful with c_str()! */
+ cargs.push_back(program.c_str());
+ for (Strings::const_iterator i = args.begin(); i != args.end(); ++i)
+ cargs.push_back(i->c_str());
+ cargs.push_back(0);
+
+ /* Create a pipe. */
+ Pipe pipe;
+ pipe.create();
+
+ /* Fork. */
+ Pid pid;
+ pid = maybeVfork();
+
+ switch (pid) {
+
+ case -1:
+ throw SysError("unable to fork");
+
+ case 0: /* child */
+ try {
+ if (dup2(pipe.writeSide, STDOUT_FILENO) == -1)
+ throw SysError("dupping stdout");
+
+ if (searchPath)
+ execvp(program.c_str(), (char * *) &cargs[0]);
+ else
+ execv(program.c_str(), (char * *) &cargs[0]);
+ throw SysError(format("executing `%1%'") % program);
+
+ } catch (std::exception & e) {
+ writeToStderr("error: " + string(e.what()) + "\n");
+ }
+ _exit(1);
+ }
+
+ /* Parent. */
+
+ pipe.writeSide.close();
+
+ string result = drainFD(pipe.readSide);
+
+ /* Wait for the child to finish. */
+ int status = pid.wait(true);
+ if (!statusOk(status))
+ throw Error(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");
+}
+
+
+#if HAVE_VFORK
+pid_t (*maybeVfork)() = vfork;
+#else
+pid_t (*maybeVfork)() = fork;
+#endif
+
+
+//////////////////////////////////////////////////////////////////////
+
+
+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 Error(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;
+}
+
+
+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) {
+ printMsg(lvlError, format("error (ignored): %1%") % e.what());
+ }
+}
+
+
+}