| // Copyright 2009 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <netinet/ip.h> |
| #include <signal.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/select.h> |
| #include <sys/socket.h> |
| #include <sys/stat.h> |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| |
| #include "include/v8-container.h" |
| #include "include/v8-template.h" |
| #include "src/d8/d8.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, |
| const 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, nullptr); |
| time_t seconds = time_now.tv_sec - start_time.tv_sec; |
| gone = static_cast<int>(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 : nullptr); |
| 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, nullptr); |
| // Careful about overflow. |
| int seconds = static_cast<int>(time_now.tv_sec - start_time.tv_sec); |
| if (seconds > 100) { |
| if (seconds * 1000 > total_time) return true; |
| return false; |
| } |
| int useconds = static_cast<int>(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_, nullptr, 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] = nullptr; } |
| bool Init(Isolate* isolate, Local<Value> arg0, Local<Array> command_args) { |
| String::Utf8Value prog(isolate, arg0); |
| if (*prog == nullptr) { |
| isolate->ThrowError( |
| "os.system(): String conversion of program name failed"); |
| 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++) { |
| Local<Value> arg( |
| command_args |
| ->Get(isolate->GetCurrentContext(), Integer::New(isolate, j)) |
| .ToLocalChecked()); |
| String::Utf8Value utf8_arg(isolate, arg); |
| if (*utf8_arg == nullptr) { |
| exec_args_[i] = nullptr; // Consistent state for destructor. |
| isolate->ThrowError( |
| "os.system(): String conversion of argument failed."); |
| 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] = nullptr; |
| return true; |
| } |
| ~ExecArgs() { |
| for (unsigned i = 0; i < kMaxArgs; i++) { |
| if (exec_args_[i] == nullptr) { |
| return; |
| } |
| delete[] exec_args_[i]; |
| exec_args_[i] = nullptr; |
| } |
| } |
| static const unsigned kMaxArgs = 1000; |
| char* const* arg_array() const { return exec_args_; } |
| const char* arg0() const { 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 v8::FunctionCallbackInfo<v8::Value>& info, |
| int* read_timeout, int* total_timeout) { |
| if (info.Length() > 3) { |
| if (info[3]->IsNumber()) { |
| *total_timeout = info[3] |
| ->Int32Value(info.GetIsolate()->GetCurrentContext()) |
| .FromJust(); |
| } else { |
| info.GetIsolate()->ThrowError("system: Argument 4 must be a number"); |
| return false; |
| } |
| } |
| if (info.Length() > 2) { |
| if (info[2]->IsNumber()) { |
| *read_timeout = info[2] |
| ->Int32Value(info.GetIsolate()->GetCurrentContext()) |
| .FromJust(); |
| } else { |
| info.GetIsolate()->ThrowError("system: Argument 3 must be a number"); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| namespace { |
| v8::Local<v8::String> v8_strerror(v8::Isolate* isolate, int err) { |
| return v8::String::NewFromUtf8(isolate, strerror(err)).ToLocalChecked(); |
| } |
| } // namespace |
| |
| 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, |
| const 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; |
| ssize_t bytes_written; |
| do { |
| bytes_written = write(exec_error_fds[kWriteFD], &err, sizeof(err)); |
| } while (bytes_written == -1 && errno == EINTR); |
| // 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(Isolate* isolate, int* exec_error_fds) { |
| ssize_t 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) { |
| isolate->ThrowError(v8_strerror(isolate, 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 Local<Value> GetStdout(Isolate* isolate, int child_fd, |
| const struct timeval& start_time, |
| int read_timeout, int total_timeout) { |
| Local<String> accumulator = String::Empty(isolate); |
| |
| int fullness = 0; |
| static const int kStdoutReadBufferSize = 4096; |
| char buffer[kStdoutReadBufferSize]; |
| |
| if (fcntl(child_fd, F_SETFL, O_NONBLOCK) != 0) { |
| return isolate->ThrowError(v8_strerror(isolate, errno)); |
| } |
| |
| int bytes_read; |
| do { |
| bytes_read = static_cast<int>( |
| 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 isolate->ThrowError("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); |
| Local<String> addition = |
| String::NewFromUtf8(isolate, buffer, NewStringType::kNormal, length) |
| .ToLocalChecked(); |
| accumulator = String::Concat(isolate, accumulator, addition); |
| 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. |
| // |
| // We're disabling usage of waitid in Mac OS X because it doesn't work for us: |
| // a parent process hangs on waiting while a child process is already a zombie. |
| // See http://code.google.com/p/v8/issues/detail?id=401. |
| #if defined(WNOWAIT) && !defined(ANDROID) && !defined(__APPLE__) && \ |
| !defined(__NetBSD__) && !defined(__Fuchsia__) |
| #if !defined(__FreeBSD__) |
| #define HAS_WAITID 1 |
| #endif |
| #endif |
| |
| // Get exit status of child. |
| static bool WaitForChild(Isolate* isolate, int pid, |
| ZombieProtector& child_waiter, |
| const 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))) { |
| isolate->ThrowError("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); |
| isolate->ThrowError(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); |
| isolate->ThrowError(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)); |
| isolate->ThrowError(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); |
| isolate->ThrowError(message); |
| return false; |
| } |
| |
| #endif // No waitid call. |
| |
| return true; |
| } |
| |
| #undef HAS_WAITID |
| |
| // Implementation of the system() function (see d8.h for details). |
| void Shell::System(const v8::FunctionCallbackInfo<v8::Value>& info) { |
| DCHECK(i::ValidateCallbackInfo(info)); |
| HandleScope scope(info.GetIsolate()); |
| int read_timeout = -1; |
| int total_timeout = -1; |
| if (!GetTimeouts(info, &read_timeout, &total_timeout)) return; |
| Local<Array> command_args; |
| if (info.Length() > 1) { |
| if (!info[1]->IsArray()) { |
| info.GetIsolate()->ThrowError("system: Argument 2 must be an array"); |
| return; |
| } |
| command_args = info[1].As<Array>(); |
| } else { |
| command_args = Array::New(info.GetIsolate(), 0); |
| } |
| if (command_args->Length() > ExecArgs::kMaxArgs) { |
| info.GetIsolate()->ThrowError("Too many arguments to system()"); |
| return; |
| } |
| if (info.Length() < 1) { |
| info.GetIsolate()->ThrowError("Too few arguments to system()"); |
| return; |
| } |
| |
| struct timeval start_time; |
| gettimeofday(&start_time, nullptr); |
| |
| ExecArgs exec_args; |
| if (!exec_args.Init(info.GetIsolate(), info[0], command_args)) { |
| return; |
| } |
| int exec_error_fds[2]; |
| int stdout_fds[2]; |
| |
| if (pipe(exec_error_fds) != 0) { |
| info.GetIsolate()->ThrowError("pipe syscall failed."); |
| return; |
| } |
| if (pipe(stdout_fds) != 0) { |
| info.GetIsolate()->ThrowError("pipe syscall failed."); |
| return; |
| } |
| |
| 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]); |
| |
| Isolate* isolate = info.GetIsolate(); |
| if (!ChildLaunchedOK(isolate, exec_error_fds)) return; |
| |
| Local<Value> accumulator = GetStdout(isolate, stdout_fds[kReadFD], start_time, |
| read_timeout, total_timeout); |
| if (accumulator->IsUndefined()) { |
| kill(pid, SIGINT); // On timeout, kill the subprocess. |
| info.GetReturnValue().Set(accumulator); |
| return; |
| } |
| |
| if (!WaitForChild(isolate, pid, child_waiter, start_time, read_timeout, |
| total_timeout)) { |
| return; |
| } |
| |
| info.GetReturnValue().Set(accumulator); |
| } |
| |
| void Shell::ChangeDirectory(const v8::FunctionCallbackInfo<v8::Value>& info) { |
| DCHECK(i::ValidateCallbackInfo(info)); |
| if (info.Length() != 1) { |
| info.GetIsolate()->ThrowError("chdir() takes one argument"); |
| return; |
| } |
| String::Utf8Value directory(info.GetIsolate(), info[0]); |
| if (*directory == nullptr) { |
| info.GetIsolate()->ThrowError( |
| "os.chdir(): String conversion of argument failed."); |
| return; |
| } |
| if (chdir(*directory) != 0) { |
| info.GetIsolate()->ThrowError(v8_strerror(info.GetIsolate(), errno)); |
| return; |
| } |
| } |
| |
| void Shell::SetUMask(const v8::FunctionCallbackInfo<v8::Value>& info) { |
| DCHECK(i::ValidateCallbackInfo(info)); |
| if (info.Length() != 1) { |
| info.GetIsolate()->ThrowError("umask() takes one argument"); |
| return; |
| } |
| if (info[0]->IsNumber()) { |
| int previous = umask( |
| info[0]->Int32Value(info.GetIsolate()->GetCurrentContext()).FromJust()); |
| info.GetReturnValue().Set(previous); |
| return; |
| } else { |
| info.GetIsolate()->ThrowError("umask() argument must be numeric"); |
| return; |
| } |
| } |
| |
| static bool CheckItsADirectory(Isolate* isolate, char* directory) { |
| struct stat stat_buf; |
| int stat_result = stat(directory, &stat_buf); |
| if (stat_result != 0) { |
| isolate->ThrowError(v8_strerror(isolate, errno)); |
| return false; |
| } |
| if ((stat_buf.st_mode & S_IFDIR) != 0) return true; |
| isolate->ThrowError(v8_strerror(isolate, EEXIST)); |
| return false; |
| } |
| |
| // Returns true for success. Creates intermediate directories as needed. No |
| // error if the directory exists already. |
| static bool mkdirp(Isolate* isolate, char* directory, mode_t mask) { |
| int result = mkdir(directory, mask); |
| if (result == 0) return true; |
| if (errno == EEXIST) { |
| return CheckItsADirectory(isolate, directory); |
| } else if (errno == ENOENT) { // Intermediate path element is missing. |
| char* last_slash = strrchr(directory, '/'); |
| if (last_slash == nullptr) { |
| isolate->ThrowError(v8_strerror(isolate, errno)); |
| return false; |
| } |
| *last_slash = 0; |
| if (!mkdirp(isolate, directory, mask)) return false; |
| *last_slash = '/'; |
| result = mkdir(directory, mask); |
| if (result == 0) return true; |
| if (errno == EEXIST) { |
| return CheckItsADirectory(isolate, directory); |
| } |
| isolate->ThrowError(v8_strerror(isolate, errno)); |
| return false; |
| } else { |
| isolate->ThrowError(v8_strerror(isolate, errno)); |
| return false; |
| } |
| } |
| |
| void Shell::MakeDirectory(const v8::FunctionCallbackInfo<v8::Value>& info) { |
| DCHECK(i::ValidateCallbackInfo(info)); |
| mode_t mask = 0777; |
| if (info.Length() == 2) { |
| if (info[1]->IsNumber()) { |
| mask = info[1] |
| ->Int32Value(info.GetIsolate()->GetCurrentContext()) |
| .FromJust(); |
| } else { |
| info.GetIsolate()->ThrowError("mkdirp() second argument must be numeric"); |
| return; |
| } |
| } else if (info.Length() != 1) { |
| info.GetIsolate()->ThrowError("mkdirp() takes one or two arguments"); |
| return; |
| } |
| String::Utf8Value directory(info.GetIsolate(), info[0]); |
| if (*directory == nullptr) { |
| info.GetIsolate()->ThrowError( |
| "os.mkdirp(): String conversion of argument failed."); |
| return; |
| } |
| mkdirp(info.GetIsolate(), *directory, mask); |
| } |
| |
| void Shell::RemoveDirectory(const v8::FunctionCallbackInfo<v8::Value>& info) { |
| DCHECK(i::ValidateCallbackInfo(info)); |
| if (info.Length() != 1) { |
| info.GetIsolate()->ThrowError("rmdir() takes one or two arguments"); |
| return; |
| } |
| String::Utf8Value directory(info.GetIsolate(), info[0]); |
| if (*directory == nullptr) { |
| info.GetIsolate()->ThrowError( |
| "os.rmdir(): String conversion of argument failed."); |
| return; |
| } |
| rmdir(*directory); |
| } |
| |
| void Shell::SetEnvironment(const v8::FunctionCallbackInfo<v8::Value>& info) { |
| DCHECK(i::ValidateCallbackInfo(info)); |
| if (info.Length() != 2) { |
| info.GetIsolate()->ThrowError("setenv() takes two arguments"); |
| return; |
| } |
| String::Utf8Value var(info.GetIsolate(), info[0]); |
| String::Utf8Value value(info.GetIsolate(), info[1]); |
| if (*var == nullptr) { |
| info.GetIsolate()->ThrowError( |
| "os.setenv(): String conversion of variable name failed."); |
| return; |
| } |
| if (*value == nullptr) { |
| info.GetIsolate()->ThrowError( |
| "os.setenv(): String conversion of variable contents failed."); |
| return; |
| } |
| setenv(*var, *value, 1); |
| } |
| |
| void Shell::UnsetEnvironment(const v8::FunctionCallbackInfo<v8::Value>& info) { |
| DCHECK(i::ValidateCallbackInfo(info)); |
| if (info.Length() != 1) { |
| info.GetIsolate()->ThrowError("unsetenv() takes one argument"); |
| return; |
| } |
| String::Utf8Value var(info.GetIsolate(), info[0]); |
| if (*var == nullptr) { |
| info.GetIsolate()->ThrowError( |
| "os.setenv(): String conversion of variable name failed."); |
| return; |
| } |
| unsetenv(*var); |
| } |
| |
| char* Shell::ReadCharsFromTcpPort(const char* name, int* size_out) { |
| DCHECK_GE(Shell::options.read_from_tcp_port, 0); |
| |
| int sockfd = socket(PF_INET, SOCK_STREAM, 0); |
| if (sockfd < 0) { |
| fprintf(stderr, "Failed to create IPv4 socket\n"); |
| return nullptr; |
| } |
| |
| // Create an address for localhost:PORT where PORT is specified by the shell |
| // option --read-from-tcp-port. |
| sockaddr_in serv_addr; |
| memset(&serv_addr, 0, sizeof(sockaddr_in)); |
| serv_addr.sin_family = AF_INET; |
| serv_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
| serv_addr.sin_port = htons(Shell::options.read_from_tcp_port); |
| |
| if (connect(sockfd, reinterpret_cast<sockaddr*>(&serv_addr), |
| sizeof(serv_addr)) < 0) { |
| fprintf(stderr, "Failed to connect to localhost:%d\n", |
| Shell::options.read_from_tcp_port.get()); |
| close(sockfd); |
| return nullptr; |
| } |
| |
| // The file server follows the simple protocol for requesting and receiving |
| // a file with a given filename: |
| // |
| // REQUEST client -> server: {filename}"\0" |
| // RESPONSE server -> client: {4-byte file-length}{file contents} |
| // |
| // i.e. the request sends the filename with a null terminator, and response |
| // sends the file contents by sending the length (as a 4-byte big-endian |
| // value) and the contents. |
| |
| // If the file length is <0, there was an error sending the file, and the |
| // rest of the response is undefined (and may, in the future, contain an error |
| // message). The socket should be closed to avoid trying to interpret the |
| // undefined data. |
| |
| // REQUEST |
| // Send the filename. |
| size_t sent_len = 0; |
| size_t name_len = strlen(name) + 1; // Includes the null terminator |
| while (sent_len < name_len) { |
| ssize_t sent_now = send(sockfd, name + sent_len, name_len - sent_len, 0); |
| if (sent_now < 0) { |
| fprintf(stderr, "Failed to send %s to localhost:%d\n", name, |
| Shell::options.read_from_tcp_port.get()); |
| close(sockfd); |
| return nullptr; |
| } |
| sent_len += sent_now; |
| } |
| |
| // RESPONSE |
| // Receive the file. |
| ssize_t received = 0; |
| |
| // First, read the (zero-terminated) file length. |
| uint32_t big_endian_file_length; |
| received = recv(sockfd, &big_endian_file_length, 4, 0); |
| // We need those 4 bytes to read off the file length. |
| if (received < 4) { |
| fprintf(stderr, "Failed to receive %s's length from localhost:%d\n", name, |
| Shell::options.read_from_tcp_port.get()); |
| close(sockfd); |
| return nullptr; |
| } |
| // Reinterpretet the received file length as a signed big-endian integer. |
| int32_t file_length = base::bit_cast<int32_t>(htonl(big_endian_file_length)); |
| |
| if (file_length < 0) { |
| fprintf(stderr, "Received length %d for %s from localhost:%d\n", |
| file_length, name, Shell::options.read_from_tcp_port.get()); |
| close(sockfd); |
| return nullptr; |
| } |
| |
| // Allocate the output array. |
| char* chars = new char[file_length]; |
| |
| // Now keep receiving and copying until the whole file is received. |
| ssize_t total_received = 0; |
| while (total_received < file_length) { |
| received = |
| recv(sockfd, chars + total_received, file_length - total_received, 0); |
| if (received < 0) { |
| fprintf(stderr, "Failed to receive %s from localhost:%d\n", name, |
| Shell::options.read_from_tcp_port.get()); |
| close(sockfd); |
| delete[] chars; |
| return nullptr; |
| } |
| total_received += received; |
| } |
| |
| close(sockfd); |
| *size_out = file_length; |
| return chars; |
| } |
| |
| void Shell::AddOSMethods(Isolate* isolate, Local<ObjectTemplate> os_templ) { |
| if (options.enable_os_system) { |
| os_templ->Set(isolate, "system", FunctionTemplate::New(isolate, System)); |
| } |
| os_templ->Set(isolate, "chdir", |
| FunctionTemplate::New(isolate, ChangeDirectory)); |
| os_templ->Set(isolate, "setenv", |
| FunctionTemplate::New(isolate, SetEnvironment)); |
| os_templ->Set(isolate, "unsetenv", |
| FunctionTemplate::New(isolate, UnsetEnvironment)); |
| os_templ->Set(isolate, "umask", FunctionTemplate::New(isolate, SetUMask)); |
| os_templ->Set(isolate, "mkdirp", |
| FunctionTemplate::New(isolate, MakeDirectory)); |
| os_templ->Set(isolate, "rmdir", |
| FunctionTemplate::New(isolate, RemoveDirectory)); |
| } |
| |
| } // namespace v8 |