diff options
Diffstat (limited to 'lldb/source/Host/linux/ProcessLauncherLinux.cpp')
| -rw-r--r-- | lldb/source/Host/linux/ProcessLauncherLinux.cpp | 330 |
1 files changed, 167 insertions, 163 deletions
diff --git a/lldb/source/Host/linux/ProcessLauncherLinux.cpp b/lldb/source/Host/linux/ProcessLauncherLinux.cpp index 2e5f4e5e822..444a8fdd43c 100644 --- a/lldb/source/Host/linux/ProcessLauncherLinux.cpp +++ b/lldb/source/Host/linux/ProcessLauncherLinux.cpp @@ -25,189 +25,193 @@ using namespace lldb; using namespace lldb_private; -static void -FixupEnvironment(Args &env) -{ +static void FixupEnvironment(Args &env) { #ifdef __ANDROID_NDK__ - // If there is no PATH variable specified inside the environment then set the path to /system/bin. - // It is required because the default path used by execve() is wrong on android. - static const char *path = "PATH="; - static const int path_len = ::strlen(path); - for (const char **args = env.GetConstArgumentVector(); *args; ++args) - if (::strncmp(path, *args, path_len) == 0) - return; - env.AppendArgument("PATH=/system/bin"); + // If there is no PATH variable specified inside the environment then set the + // path to /system/bin. + // It is required because the default path used by execve() is wrong on + // android. + static const char *path = "PATH="; + static const int path_len = ::strlen(path); + for (const char **args = env.GetConstArgumentVector(); *args; ++args) + if (::strncmp(path, *args, path_len) == 0) + return; + env.AppendArgument("PATH=/system/bin"); #endif } -static void LLVM_ATTRIBUTE_NORETURN -ExitWithError(int error_fd, const char *operation) -{ - std::ostringstream os; - os << operation << " failed: " << strerror(errno); - write(error_fd, os.str().data(), os.str().size()); - close(error_fd); - _exit(1); +static void LLVM_ATTRIBUTE_NORETURN ExitWithError(int error_fd, + const char *operation) { + std::ostringstream os; + os << operation << " failed: " << strerror(errno); + write(error_fd, os.str().data(), os.str().size()); + close(error_fd); + _exit(1); } -static void -DupDescriptor(int error_fd, const FileSpec &file_spec, int fd, int flags) -{ - int target_fd = ::open(file_spec.GetCString(), flags, 0666); +static void DupDescriptor(int error_fd, const FileSpec &file_spec, int fd, + int flags) { + int target_fd = ::open(file_spec.GetCString(), flags, 0666); - if (target_fd == -1) - ExitWithError(error_fd, "DupDescriptor-open"); + if (target_fd == -1) + ExitWithError(error_fd, "DupDescriptor-open"); - if (target_fd == fd) - return; - - if (::dup2(target_fd, fd) == -1) - ExitWithError(error_fd, "DupDescriptor-dup2"); - - ::close(target_fd); + if (target_fd == fd) return; -} - -static void LLVM_ATTRIBUTE_NORETURN -ChildFunc(int error_fd, const ProcessLaunchInfo &info) -{ - // First, make sure we disable all logging. If we are logging to stdout, our logs can be - // mistaken for inferior output. - Log::DisableAllLogChannels(nullptr); - - // Do not inherit setgid powers. - if (setgid(getgid()) != 0) - ExitWithError(error_fd, "setgid"); - - if (info.GetFlags().Test(eLaunchFlagLaunchInSeparateProcessGroup)) - { - if (setpgid(0, 0) != 0) - ExitWithError(error_fd, "setpgid"); - } - for (size_t i = 0; i < info.GetNumFileActions(); ++i) - { - const FileAction &action = *info.GetFileActionAtIndex(i); - switch (action.GetAction()) - { - case FileAction::eFileActionClose: - if (close(action.GetFD()) != 0) - ExitWithError(error_fd, "close"); - break; - case FileAction::eFileActionDuplicate: - if (dup2(action.GetFD(), action.GetActionArgument()) == -1) - ExitWithError(error_fd, "dup2"); - break; - case FileAction::eFileActionOpen: - DupDescriptor(error_fd, action.GetFileSpec(), action.GetFD(), action.GetActionArgument()); - break; - case FileAction::eFileActionNone: - break; - } - } - - const char **argv = info.GetArguments().GetConstArgumentVector(); - - // Change working directory - if (info.GetWorkingDirectory() && 0 != ::chdir(info.GetWorkingDirectory().GetCString())) - ExitWithError(error_fd, "chdir"); + if (::dup2(target_fd, fd) == -1) + ExitWithError(error_fd, "DupDescriptor-dup2"); - // Disable ASLR if requested. - if (info.GetFlags().Test(lldb::eLaunchFlagDisableASLR)) - { - const unsigned long personality_get_current = 0xffffffff; - int value = personality(personality_get_current); - if (value == -1) - ExitWithError(error_fd, "personality get"); - - value = personality(ADDR_NO_RANDOMIZE | value); - if (value == -1) - ExitWithError(error_fd, "personality set"); - } - - Args env = info.GetEnvironmentEntries(); - FixupEnvironment(env); - const char **envp = env.GetConstArgumentVector(); - - // Clear the signal mask to prevent the child from being affected by - // any masking done by the parent. - sigset_t set; - if (sigemptyset(&set) != 0 || pthread_sigmask(SIG_SETMASK, &set, nullptr) != 0) - ExitWithError(error_fd, "pthread_sigmask"); - - if (info.GetFlags().Test(eLaunchFlagDebug)) - { - // HACK: - // Close everything besides stdin, stdout, and stderr that has no file - // action to avoid leaking. Only do this when debugging, as elsewhere we actually rely on - // passing open descriptors to child processes. - for (int fd = 3; fd < sysconf(_SC_OPEN_MAX); ++fd) - if (!info.GetFileActionForFD(fd) && fd != error_fd) - close(fd); - - // Start tracing this child that is about to exec. - if (ptrace(PTRACE_TRACEME, 0, nullptr, nullptr) == -1) - ExitWithError(error_fd, "ptrace"); - } + ::close(target_fd); + return; +} - // Execute. We should never return... - execve(argv[0], const_cast<char *const *>(argv), const_cast<char *const *>(envp)); - - if (errno == ETXTBSY) - { - // On android M and earlier we can get this error because the adb deamon can hold a write - // handle on the executable even after it has finished uploading it. This state lasts - // only a short time and happens only when there are many concurrent adb commands being - // issued, such as when running the test suite. (The file remains open when someone does - // an "adb shell" command in the fork() child before it has had a chance to exec.) Since - // this state should clear up quickly, wait a while and then give it one more go. - usleep(50000); - execve(argv[0], const_cast<char *const *>(argv), const_cast<char *const *>(envp)); +static void LLVM_ATTRIBUTE_NORETURN ChildFunc(int error_fd, + const ProcessLaunchInfo &info) { + // First, make sure we disable all logging. If we are logging to stdout, our + // logs can be + // mistaken for inferior output. + Log::DisableAllLogChannels(nullptr); + + // Do not inherit setgid powers. + if (setgid(getgid()) != 0) + ExitWithError(error_fd, "setgid"); + + if (info.GetFlags().Test(eLaunchFlagLaunchInSeparateProcessGroup)) { + if (setpgid(0, 0) != 0) + ExitWithError(error_fd, "setpgid"); + } + + for (size_t i = 0; i < info.GetNumFileActions(); ++i) { + const FileAction &action = *info.GetFileActionAtIndex(i); + switch (action.GetAction()) { + case FileAction::eFileActionClose: + if (close(action.GetFD()) != 0) + ExitWithError(error_fd, "close"); + break; + case FileAction::eFileActionDuplicate: + if (dup2(action.GetFD(), action.GetActionArgument()) == -1) + ExitWithError(error_fd, "dup2"); + break; + case FileAction::eFileActionOpen: + DupDescriptor(error_fd, action.GetFileSpec(), action.GetFD(), + action.GetActionArgument()); + break; + case FileAction::eFileActionNone: + break; } - - // ...unless exec fails. In which case we definitely need to end the child here. - ExitWithError(error_fd, "execve"); + } + + const char **argv = info.GetArguments().GetConstArgumentVector(); + + // Change working directory + if (info.GetWorkingDirectory() && + 0 != ::chdir(info.GetWorkingDirectory().GetCString())) + ExitWithError(error_fd, "chdir"); + + // Disable ASLR if requested. + if (info.GetFlags().Test(lldb::eLaunchFlagDisableASLR)) { + const unsigned long personality_get_current = 0xffffffff; + int value = personality(personality_get_current); + if (value == -1) + ExitWithError(error_fd, "personality get"); + + value = personality(ADDR_NO_RANDOMIZE | value); + if (value == -1) + ExitWithError(error_fd, "personality set"); + } + + Args env = info.GetEnvironmentEntries(); + FixupEnvironment(env); + const char **envp = env.GetConstArgumentVector(); + + // Clear the signal mask to prevent the child from being affected by + // any masking done by the parent. + sigset_t set; + if (sigemptyset(&set) != 0 || + pthread_sigmask(SIG_SETMASK, &set, nullptr) != 0) + ExitWithError(error_fd, "pthread_sigmask"); + + if (info.GetFlags().Test(eLaunchFlagDebug)) { + // HACK: + // Close everything besides stdin, stdout, and stderr that has no file + // action to avoid leaking. Only do this when debugging, as elsewhere we + // actually rely on + // passing open descriptors to child processes. + for (int fd = 3; fd < sysconf(_SC_OPEN_MAX); ++fd) + if (!info.GetFileActionForFD(fd) && fd != error_fd) + close(fd); + + // Start tracing this child that is about to exec. + if (ptrace(PTRACE_TRACEME, 0, nullptr, nullptr) == -1) + ExitWithError(error_fd, "ptrace"); + } + + // Execute. We should never return... + execve(argv[0], const_cast<char *const *>(argv), + const_cast<char *const *>(envp)); + + if (errno == ETXTBSY) { + // On android M and earlier we can get this error because the adb deamon can + // hold a write + // handle on the executable even after it has finished uploading it. This + // state lasts + // only a short time and happens only when there are many concurrent adb + // commands being + // issued, such as when running the test suite. (The file remains open when + // someone does + // an "adb shell" command in the fork() child before it has had a chance to + // exec.) Since + // this state should clear up quickly, wait a while and then give it one + // more go. + usleep(50000); + execve(argv[0], const_cast<char *const *>(argv), + const_cast<char *const *>(envp)); + } + + // ...unless exec fails. In which case we definitely need to end the child + // here. + ExitWithError(error_fd, "execve"); } HostProcess -ProcessLauncherLinux::LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error) -{ - char exe_path[PATH_MAX]; - launch_info.GetExecutableFile().GetPath(exe_path, sizeof(exe_path)); - - // A pipe used by the child process to report errors. - PipePosix pipe; - const bool child_processes_inherit = false; - error = pipe.CreateNew(child_processes_inherit); - if (error.Fail()) - return HostProcess(); - - ::pid_t pid = ::fork(); - if (pid == -1) - { - // Fork failed - error.SetErrorStringWithFormat("Fork failed with error message: %s", strerror(errno)); - return HostProcess(LLDB_INVALID_PROCESS_ID); - } - if (pid == 0) - { - // child process - pipe.CloseReadFileDescriptor(); - ChildFunc(pipe.ReleaseWriteFileDescriptor(), launch_info); - } +ProcessLauncherLinux::LaunchProcess(const ProcessLaunchInfo &launch_info, + Error &error) { + char exe_path[PATH_MAX]; + launch_info.GetExecutableFile().GetPath(exe_path, sizeof(exe_path)); + + // A pipe used by the child process to report errors. + PipePosix pipe; + const bool child_processes_inherit = false; + error = pipe.CreateNew(child_processes_inherit); + if (error.Fail()) + return HostProcess(); - // parent process + ::pid_t pid = ::fork(); + if (pid == -1) { + // Fork failed + error.SetErrorStringWithFormat("Fork failed with error message: %s", + strerror(errno)); + return HostProcess(LLDB_INVALID_PROCESS_ID); + } + if (pid == 0) { + // child process + pipe.CloseReadFileDescriptor(); + ChildFunc(pipe.ReleaseWriteFileDescriptor(), launch_info); + } - pipe.CloseWriteFileDescriptor(); - char buf[1000]; - int r = read(pipe.GetReadFileDescriptor(), buf, sizeof buf); + // parent process - if (r == 0) - return HostProcess(pid); // No error. We're done. + pipe.CloseWriteFileDescriptor(); + char buf[1000]; + int r = read(pipe.GetReadFileDescriptor(), buf, sizeof buf); - error.SetErrorString(buf); + if (r == 0) + return HostProcess(pid); // No error. We're done. - waitpid(pid, nullptr, 0); + error.SetErrorString(buf); - return HostProcess(); + waitpid(pid, nullptr, 0); + + return HostProcess(); } |
