| // Copyright 2009 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following |
| // disclaimer in the documentation and/or other materials provided |
| // with the distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| |
| #include <stdlib.h> |
| #include <errno.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <sys/time.h> |
| #include <time.h> |
| #include <unistd.h> |
| #include <fcntl.h> |
| #include <sys/wait.h> |
| #include <signal.h> |
| |
| |
| #include "d8.h" |
| #include "d8-debug.h" |
| #include "debug.h" |
| |
| |
| namespace v8 { |
| |
| |
| // If the buffer ends in the middle of a UTF-8 sequence then we return |
| // the length of the string up to but not including the incomplete UTF-8 |
| // sequence. If the buffer ends with a valid UTF-8 sequence then we |
| // return the whole buffer. |
| static int LengthWithoutIncompleteUtf8(char* buffer, int len) { |
| int answer = len; |
| // 1-byte encoding. |
| static const int kUtf8SingleByteMask = 0x80; |
| static const int kUtf8SingleByteValue = 0x00; |
| // 2-byte encoding. |
| static const int kUtf8TwoByteMask = 0xe0; |
| static const int kUtf8TwoByteValue = 0xc0; |
| // 3-byte encoding. |
| static const int kUtf8ThreeByteMask = 0xf0; |
| static const int kUtf8ThreeByteValue = 0xe0; |
| // 4-byte encoding. |
| static const int kUtf8FourByteMask = 0xf8; |
| static const int kUtf8FourByteValue = 0xf0; |
| // Subsequent bytes of a multi-byte encoding. |
| static const int kMultiByteMask = 0xc0; |
| static const int kMultiByteValue = 0x80; |
| int multi_byte_bytes_seen = 0; |
| while (answer > 0) { |
| int c = buffer[answer - 1]; |
| // Ends in valid single-byte sequence? |
| if ((c & kUtf8SingleByteMask) == kUtf8SingleByteValue) return answer; |
| // Ends in one or more subsequent bytes of a multi-byte value? |
| if ((c & kMultiByteMask) == kMultiByteValue) { |
| multi_byte_bytes_seen++; |
| answer--; |
| } else { |
| if ((c & kUtf8TwoByteMask) == kUtf8TwoByteValue) { |
| if (multi_byte_bytes_seen >= 1) { |
| return answer + 2; |
| } |
| return answer - 1; |
| } else if ((c & kUtf8ThreeByteMask) == kUtf8ThreeByteValue) { |
| if (multi_byte_bytes_seen >= 2) { |
| return answer + 3; |
| } |
| return answer - 1; |
| } else if ((c & kUtf8FourByteMask) == kUtf8FourByteValue) { |
| if (multi_byte_bytes_seen >= 3) { |
| return answer + 4; |
| } |
| return answer - 1; |
| } else { |
| return answer; // Malformed UTF-8. |
| } |
| } |
| } |
| return 0; |
| } |
| |
| |
| // Suspends the thread until there is data available from the child process. |
| // Returns false on timeout, true on data ready. |
| static bool WaitOnFD(int fd, |
| int read_timeout, |
| int total_timeout, |
| struct timeval& start_time) { |
| fd_set readfds, writefds, exceptfds; |
| struct timeval timeout; |
| int gone = 0; |
| if (total_timeout != -1) { |
| struct timeval time_now; |
| gettimeofday(&time_now, NULL); |
| int seconds = time_now.tv_sec - start_time.tv_sec; |
| gone = seconds * 1000 + (time_now.tv_usec - start_time.tv_usec) / 1000; |
| if (gone >= total_timeout) return false; |
| } |
| FD_ZERO(&readfds); |
| FD_ZERO(&writefds); |
| FD_ZERO(&exceptfds); |
| FD_SET(fd, &readfds); |
| FD_SET(fd, &exceptfds); |
| if (read_timeout == -1 || |
| (total_timeout != -1 && total_timeout - gone < read_timeout)) { |
| read_timeout = total_timeout - gone; |
| } |
| timeout.tv_usec = (read_timeout % 1000) * 1000; |
| timeout.tv_sec = read_timeout / 1000; |
| int number_of_fds_ready = select(fd + 1, |
| &readfds, |
| &writefds, |
| &exceptfds, |
| read_timeout != -1 ? &timeout : NULL); |
| return number_of_fds_ready == 1; |
| } |
| |
| |
| // Checks whether we ran out of time on the timeout. Returns true if we ran out |
| // of time, false if we still have time. |
| static bool TimeIsOut(const struct timeval& start_time, const int& total_time) { |
| if (total_time == -1) return false; |
| struct timeval time_now; |
| gettimeofday(&time_now, NULL); |
| // Careful about overflow. |
| int seconds = time_now.tv_sec - start_time.tv_sec; |
| if (seconds > 100) { |
| if (seconds * 1000 > total_time) return true; |
| return false; |
| } |
| int useconds = time_now.tv_usec - start_time.tv_usec; |
| if (seconds * 1000000 + useconds > total_time * 1000) { |
| return true; |
| } |
| return false; |
| } |
| |
| |
| // A utility class that does a non-hanging waitpid on the child process if we |
| // bail out of the System() function early. If you don't ever do a waitpid on |
| // a subprocess then it turns into one of those annoying 'zombie processes'. |
| class ZombieProtector { |
| public: |
| explicit ZombieProtector(int pid): pid_(pid) { } |
| ~ZombieProtector() { if (pid_ != 0) waitpid(pid_, NULL, 0); } |
| void ChildIsDeadNow() { pid_ = 0; } |
| private: |
| int pid_; |
| }; |
| |
| |
| // A utility class that closes a file descriptor when it goes out of scope. |
| class OpenFDCloser { |
| public: |
| explicit OpenFDCloser(int fd): fd_(fd) { } |
| ~OpenFDCloser() { close(fd_); } |
| private: |
| int fd_; |
| }; |
| |
| |
| // A utility class that takes the array of command arguments and puts then in an |
| // array of new[]ed UTF-8 C strings. Deallocates them again when it goes out of |
| // scope. |
| class ExecArgs { |
| public: |
| ExecArgs() { |
| exec_args_[0] = NULL; |
| } |
| bool Init(Handle<Value> arg0, Handle<Array> command_args) { |
| String::Utf8Value prog(arg0); |
| if (*prog == NULL) { |
| const char* message = |
| "os.system(): String conversion of program name failed"; |
| ThrowException(String::New(message)); |
| return false; |
| } |
| int len = prog.length() + 3; |
| char* c_arg = new char[len]; |
| snprintf(c_arg, len, "%s", *prog); |
| exec_args_[0] = c_arg; |
| int i = 1; |
| for (unsigned j = 0; j < command_args->Length(); i++, j++) { |
| Handle<Value> arg(command_args->Get(Integer::New(j))); |
| String::Utf8Value utf8_arg(arg); |
| if (*utf8_arg == NULL) { |
| exec_args_[i] = NULL; // Consistent state for destructor. |
| const char* message = |
| "os.system(): String conversion of argument failed."; |
| ThrowException(String::New(message)); |
| return false; |
| } |
| int len = utf8_arg.length() + 1; |
| char* c_arg = new char[len]; |
| snprintf(c_arg, len, "%s", *utf8_arg); |
| exec_args_[i] = c_arg; |
| } |
| exec_args_[i] = NULL; |
| return true; |
| } |
| ~ExecArgs() { |
| for (unsigned i = 0; i < kMaxArgs; i++) { |
| if (exec_args_[i] == NULL) { |
| return; |
| } |
| delete [] exec_args_[i]; |
| exec_args_[i] = 0; |
| } |
| } |
| static const unsigned kMaxArgs = 1000; |
| char** arg_array() { return exec_args_; } |
| char* arg0() { return exec_args_[0]; } |
| private: |
| char* exec_args_[kMaxArgs + 1]; |
| }; |
| |
| |
| // Gets the optional timeouts from the arguments to the system() call. |
| static bool GetTimeouts(const Arguments& args, |
| int* read_timeout, |
| int* total_timeout) { |
| if (args.Length() > 3) { |
| if (args[3]->IsNumber()) { |
| *total_timeout = args[3]->Int32Value(); |
| } else { |
| ThrowException(String::New("system: Argument 4 must be a number")); |
| return false; |
| } |
| } |
| if (args.Length() > 2) { |
| if (args[2]->IsNumber()) { |
| *read_timeout = args[2]->Int32Value(); |
| } else { |
| ThrowException(String::New("system: Argument 3 must be a number")); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| |
| static const int kReadFD = 0; |
| static const int kWriteFD = 1; |
| |
| |
| // This is run in the child process after fork() but before exec(). It normally |
| // ends with the child process being replaced with the desired child program. |
| // It only returns if an error occurred. |
| static void ExecSubprocess(int* exec_error_fds, |
| int* stdout_fds, |
| ExecArgs& exec_args) { |
| close(exec_error_fds[kReadFD]); // Don't need this in the child. |
| close(stdout_fds[kReadFD]); // Don't need this in the child. |
| close(1); // Close stdout. |
| dup2(stdout_fds[kWriteFD], 1); // Dup pipe fd to stdout. |
| close(stdout_fds[kWriteFD]); // Don't need the original fd now. |
| fcntl(exec_error_fds[kWriteFD], F_SETFD, FD_CLOEXEC); |
| execvp(exec_args.arg0(), exec_args.arg_array()); |
| // Only get here if the exec failed. Write errno to the parent to tell |
| // them it went wrong. If it went well the pipe is closed. |
| int err = errno; |
| write(exec_error_fds[kWriteFD], &err, sizeof(err)); |
| // Return (and exit child process). |
| } |
| |
| |
| // Runs in the parent process. Checks that the child was able to exec (closing |
| // the file desriptor), or reports an error if it failed. |
| static bool ChildLaunchedOK(int* exec_error_fds) { |
| int bytes_read; |
| int err; |
| do { |
| bytes_read = read(exec_error_fds[kReadFD], &err, sizeof(err)); |
| } while (bytes_read == -1 && errno == EINTR); |
| if (bytes_read != 0) { |
| ThrowException(String::New(strerror(err))); |
| return false; |
| } |
| return true; |
| } |
| |
| |
| // Accumulates the output from the child in a string handle. Returns true if it |
| // succeeded or false if an exception was thrown. |
| static Handle<Value> GetStdout(int child_fd, |
| struct timeval& start_time, |
| int read_timeout, |
| int total_timeout) { |
| Handle<String> accumulator = String::Empty(); |
| const char* source = "function(a, b) { return a + b; }"; |
| Handle<Value> cons_as_obj(Script::Compile(String::New(source))->Run()); |
| Handle<Function> cons_function(Function::Cast(*cons_as_obj)); |
| Handle<Value> cons_args[2]; |
| |
| int fullness = 0; |
| static const int kStdoutReadBufferSize = 4096; |
| char buffer[kStdoutReadBufferSize]; |
| |
| if (fcntl(child_fd, F_SETFL, O_NONBLOCK) != 0) { |
| return ThrowException(String::New(strerror(errno))); |
| } |
| |
| int bytes_read; |
| do { |
| bytes_read = read(child_fd, |
| buffer + fullness, |
| kStdoutReadBufferSize - fullness); |
| if (bytes_read == -1) { |
| if (errno == EAGAIN) { |
| if (!WaitOnFD(child_fd, |
| read_timeout, |
| total_timeout, |
| start_time) || |
| (TimeIsOut(start_time, total_timeout))) { |
| return ThrowException(String::New("Timed out waiting for output")); |
| } |
| continue; |
| } else if (errno == EINTR) { |
| continue; |
| } else { |
| break; |
| } |
| } |
| if (bytes_read + fullness > 0) { |
| int length = bytes_read == 0 ? |
| bytes_read + fullness : |
| LengthWithoutIncompleteUtf8(buffer, bytes_read + fullness); |
| Handle<String> addition = String::New(buffer, length); |
| cons_args[0] = accumulator; |
| cons_args[1] = addition; |
| accumulator = Handle<String>::Cast(cons_function->Call( |
| Shell::utility_context()->Global(), |
| 2, |
| cons_args)); |
| fullness = bytes_read + fullness - length; |
| memcpy(buffer, buffer + length, fullness); |
| } |
| } while (bytes_read != 0); |
| return accumulator; |
| } |
| |
| |
| // Modern Linux has the waitid call, which is like waitpid, but more useful |
| // if you want a timeout. If we don't have waitid we can't limit the time |
| // waiting for the process to exit without losing the information about |
| // whether it exited normally. In the common case this doesn't matter because |
| // we don't get here before the child has closed stdout and most programs don't |
| // do that before they exit. |
| #if defined(WNOWAIT) && !defined(ANDROID) |
| #define HAS_WAITID 1 |
| #endif |
| |
| |
| // Get exit status of child. |
| static bool WaitForChild(int pid, |
| ZombieProtector& child_waiter, |
| struct timeval& start_time, |
| int read_timeout, |
| int total_timeout) { |
| #ifdef HAS_WAITID |
| |
| siginfo_t child_info; |
| child_info.si_pid = 0; |
| int useconds = 1; |
| // Wait for child to exit. |
| while (child_info.si_pid == 0) { |
| waitid(P_PID, pid, &child_info, WEXITED | WNOHANG | WNOWAIT); |
| usleep(useconds); |
| if (useconds < 1000000) useconds <<= 1; |
| if ((read_timeout != -1 && useconds / 1000 > read_timeout) || |
| (TimeIsOut(start_time, total_timeout))) { |
| ThrowException(String::New("Timed out waiting for process to terminate")); |
| kill(pid, SIGINT); |
| return false; |
| } |
| } |
| if (child_info.si_code == CLD_KILLED) { |
| char message[999]; |
| snprintf(message, |
| sizeof(message), |
| "Child killed by signal %d", |
| child_info.si_status); |
| ThrowException(String::New(message)); |
| return false; |
| } |
| if (child_info.si_code == CLD_EXITED && child_info.si_status != 0) { |
| char message[999]; |
| snprintf(message, |
| sizeof(message), |
| "Child exited with status %d", |
| child_info.si_status); |
| ThrowException(String::New(message)); |
| return false; |
| } |
| |
| #else // No waitid call. |
| |
| int child_status; |
| waitpid(pid, &child_status, 0); // We hang here if the child doesn't exit. |
| child_waiter.ChildIsDeadNow(); |
| if (WIFSIGNALED(child_status)) { |
| char message[999]; |
| snprintf(message, |
| sizeof(message), |
| "Child killed by signal %d", |
| WTERMSIG(child_status)); |
| ThrowException(String::New(message)); |
| return false; |
| } |
| if (WEXITSTATUS(child_status) != 0) { |
| char message[999]; |
| int exit_status = WEXITSTATUS(child_status); |
| snprintf(message, |
| sizeof(message), |
| "Child exited with status %d", |
| exit_status); |
| ThrowException(String::New(message)); |
| return false; |
| } |
| |
| #endif // No waitid call. |
| |
| return true; |
| } |
| |
| |
| // Implementation of the system() function (see d8.h for details). |
| Handle<Value> Shell::System(const Arguments& args) { |
| HandleScope scope; |
| int read_timeout = -1; |
| int total_timeout = -1; |
| if (!GetTimeouts(args, &read_timeout, &total_timeout)) return v8::Undefined(); |
| Handle<Array> command_args; |
| if (args.Length() > 1) { |
| if (!args[1]->IsArray()) { |
| return ThrowException(String::New("system: Argument 2 must be an array")); |
| } |
| command_args = Handle<Array>::Cast(args[1]); |
| } else { |
| command_args = Array::New(0); |
| } |
| if (command_args->Length() > ExecArgs::kMaxArgs) { |
| return ThrowException(String::New("Too many arguments to system()")); |
| } |
| if (args.Length() < 1) { |
| return ThrowException(String::New("Too few arguments to system()")); |
| } |
| |
| struct timeval start_time; |
| gettimeofday(&start_time, NULL); |
| |
| ExecArgs exec_args; |
| if (!exec_args.Init(args[0], command_args)) { |
| return v8::Undefined(); |
| } |
| int exec_error_fds[2]; |
| int stdout_fds[2]; |
| |
| if (pipe(exec_error_fds) != 0) { |
| return ThrowException(String::New("pipe syscall failed.")); |
| } |
| if (pipe(stdout_fds) != 0) { |
| return ThrowException(String::New("pipe syscall failed.")); |
| } |
| |
| pid_t pid = fork(); |
| if (pid == 0) { // Child process. |
| ExecSubprocess(exec_error_fds, stdout_fds, exec_args); |
| exit(1); |
| } |
| |
| // Parent process. Ensure that we clean up if we exit this function early. |
| ZombieProtector child_waiter(pid); |
| close(exec_error_fds[kWriteFD]); |
| close(stdout_fds[kWriteFD]); |
| OpenFDCloser error_read_closer(exec_error_fds[kReadFD]); |
| OpenFDCloser stdout_read_closer(stdout_fds[kReadFD]); |
| |
| if (!ChildLaunchedOK(exec_error_fds)) return v8::Undefined(); |
| |
| Handle<Value> accumulator = GetStdout(stdout_fds[kReadFD], |
| start_time, |
| read_timeout, |
| total_timeout); |
| if (accumulator->IsUndefined()) { |
| kill(pid, SIGINT); // On timeout, kill the subprocess. |
| return accumulator; |
| } |
| |
| if (!WaitForChild(pid, |
| child_waiter, |
| start_time, |
| read_timeout, |
| total_timeout)) { |
| return v8::Undefined(); |
| } |
| |
| return scope.Close(accumulator); |
| } |
| |
| |
| Handle<Value> Shell::ChangeDirectory(const Arguments& args) { |
| if (args.Length() != 1) { |
| const char* message = "chdir() takes one argument"; |
| return ThrowException(String::New(message)); |
| } |
| String::Utf8Value directory(args[0]); |
| if (*directory == NULL) { |
| const char* message = "os.chdir(): String conversion of argument failed."; |
| return ThrowException(String::New(message)); |
| } |
| if (chdir(*directory) != 0) { |
| return ThrowException(String::New(strerror(errno))); |
| } |
| return v8::Undefined(); |
| } |
| |
| |
| Handle<Value> Shell::SetUMask(const Arguments& args) { |
| if (args.Length() != 1) { |
| const char* message = "umask() takes one argument"; |
| return ThrowException(String::New(message)); |
| } |
| if (args[0]->IsNumber()) { |
| mode_t mask = args[0]->Int32Value(); |
| int previous = umask(mask); |
| return Number::New(previous); |
| } else { |
| const char* message = "umask() argument must be numeric"; |
| return ThrowException(String::New(message)); |
| } |
| } |
| |
| |
| static bool CheckItsADirectory(char* directory) { |
| struct stat stat_buf; |
| int stat_result = stat(directory, &stat_buf); |
| if (stat_result != 0) { |
| ThrowException(String::New(strerror(errno))); |
| return false; |
| } |
| if ((stat_buf.st_mode & S_IFDIR) != 0) return true; |
| ThrowException(String::New(strerror(EEXIST))); |
| return false; |
| } |
| |
| |
| // Returns true for success. Creates intermediate directories as needed. No |
| // error if the directory exists already. |
| static bool mkdirp(char* directory, mode_t mask) { |
| int result = mkdir(directory, mask); |
| if (result == 0) return true; |
| if (errno == EEXIST) { |
| return CheckItsADirectory(directory); |
| } else if (errno == ENOENT) { // Intermediate path element is missing. |
| char* last_slash = strrchr(directory, '/'); |
| if (last_slash == NULL) { |
| ThrowException(String::New(strerror(errno))); |
| return false; |
| } |
| *last_slash = 0; |
| if (!mkdirp(directory, mask)) return false; |
| *last_slash = '/'; |
| result = mkdir(directory, mask); |
| if (result == 0) return true; |
| if (errno == EEXIST) { |
| return CheckItsADirectory(directory); |
| } |
| ThrowException(String::New(strerror(errno))); |
| return false; |
| } else { |
| ThrowException(String::New(strerror(errno))); |
| return false; |
| } |
| } |
| |
| |
| Handle<Value> Shell::MakeDirectory(const Arguments& args) { |
| mode_t mask = 0777; |
| if (args.Length() == 2) { |
| if (args[1]->IsNumber()) { |
| mask = args[1]->Int32Value(); |
| } else { |
| const char* message = "mkdirp() second argument must be numeric"; |
| return ThrowException(String::New(message)); |
| } |
| } else if (args.Length() != 1) { |
| const char* message = "mkdirp() takes one or two arguments"; |
| return ThrowException(String::New(message)); |
| } |
| String::Utf8Value directory(args[0]); |
| if (*directory == NULL) { |
| const char* message = "os.mkdirp(): String conversion of argument failed."; |
| return ThrowException(String::New(message)); |
| } |
| mkdirp(*directory, mask); |
| return v8::Undefined(); |
| } |
| |
| |
| Handle<Value> Shell::RemoveDirectory(const Arguments& args) { |
| if (args.Length() != 1) { |
| const char* message = "rmdir() takes one or two arguments"; |
| return ThrowException(String::New(message)); |
| } |
| String::Utf8Value directory(args[0]); |
| if (*directory == NULL) { |
| const char* message = "os.rmdir(): String conversion of argument failed."; |
| return ThrowException(String::New(message)); |
| } |
| rmdir(*directory); |
| return v8::Undefined(); |
| } |
| |
| |
| Handle<Value> Shell::SetEnvironment(const Arguments& args) { |
| if (args.Length() != 2) { |
| const char* message = "setenv() takes two arguments"; |
| return ThrowException(String::New(message)); |
| } |
| String::Utf8Value var(args[0]); |
| String::Utf8Value value(args[1]); |
| if (*var == NULL) { |
| const char* message = |
| "os.setenv(): String conversion of variable name failed."; |
| return ThrowException(String::New(message)); |
| } |
| if (*value == NULL) { |
| const char* message = |
| "os.setenv(): String conversion of variable contents failed."; |
| return ThrowException(String::New(message)); |
| } |
| setenv(*var, *value, 1); |
| return v8::Undefined(); |
| } |
| |
| |
| void Shell::AddOSMethods(Handle<ObjectTemplate> os_templ) { |
| os_templ->Set(String::New("system"), FunctionTemplate::New(System)); |
| os_templ->Set(String::New("chdir"), FunctionTemplate::New(ChangeDirectory)); |
| os_templ->Set(String::New("setenv"), FunctionTemplate::New(SetEnvironment)); |
| os_templ->Set(String::New("umask"), FunctionTemplate::New(SetUMask)); |
| os_templ->Set(String::New("mkdirp"), FunctionTemplate::New(MakeDirectory)); |
| os_templ->Set(String::New("rmdir"), FunctionTemplate::New(RemoveDirectory)); |
| } |
| |
| } // namespace v8 |