diff options
Diffstat (limited to 'src/libutil/util.cc')
| -rw-r--r-- | src/libutil/util.cc | 1145 |
1 files changed, 1145 insertions, 0 deletions
diff --git a/src/libutil/util.cc b/src/libutil/util.cc new file mode 100644 index 000000000000..9437a2f99a3c --- /dev/null +++ b/src/libutil/util.cc @@ -0,0 +1,1145 @@ +#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 format & f, unsigned int status) + : status(status) +{ + err = f.str(); +} + + +BaseError & BaseError::addPrefix(const format & f) +{ + prefix_ = f.str() + prefix_; + return *this; +} + + +SysError::SysError(const format & f) + : Error(format("%1%: %2%") % f.str() % 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 _computePathSize(const Path & path, + unsigned long long & bytes, unsigned long long & blocks) +{ + checkInterrupt(); + + struct stat st = lstat(path); + + bytes += st.st_size; + blocks += st.st_blocks; + + if (S_ISDIR(st.st_mode)) { + Strings names = readDirectory(path); + + for (Strings::iterator i = names.begin(); i != names.end(); ++i) + _computePathSize(path + "/" + *i, bytes, blocks); + } +} + + +void computePathSize(const Path & path, + unsigned long long & bytes, unsigned long long & blocks) +{ + bytes = 0; + blocks = 0; + _computePathSize(path, bytes, blocks); +} + + +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); +} + + +void makePathReadOnly(const Path & path) +{ + checkInterrupt(); + + struct stat st = lstat(path); + + if (!S_ISLNK(st.st_mode) && (st.st_mode & S_IWUSR)) { + if (chmod(path.c_str(), st.st_mode & ~S_IWUSR) == -1) + throw SysError(format("making `%1%' read-only") % path); + } + + if (S_ISDIR(st.st_mode)) { + Strings names = readDirectory(path); + for (Strings::iterator i = names.begin(); i != names.end(); ++i) + makePathReadOnly(path + "/" + *i); + } +} + + +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; +} + + +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 format & f) +{ + if (level <= verbosity) { + if (logType == ltEscapes) + std::cerr << "\033[" << escVerbosity(level) << "p" + << f.str() << "\n"; + else + printMsg_(level, f); + nest = true; + nestingLevel++; + } +} + + +void Nest::close() +{ + if (nest) { + nestingLevel--; + if (logType == ltEscapes) + std::cerr << "\033[q"; + nest = false; + } +} + + +void printMsg_(Verbosity level, const format & f) +{ + 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 % f.str()).str(); + writeToStderr(s); +} + + +void warnOnce(bool & haveWarned, const format & f) +{ + if (!haveWarned) { + printMsg(lvlError, format("warning: %1%") % f.str()); + 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()); + } +} + + +} |