diff options
| -rw-r--r-- | src/zencore/process.cpp | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/src/zencore/process.cpp b/src/zencore/process.cpp index 9cbbfa56a..af1eff19a 100644 --- a/src/zencore/process.cpp +++ b/src/zencore/process.cpp @@ -42,6 +42,10 @@ ZEN_THIRD_PARTY_INCLUDES_START # include <sys/sysctl.h> #endif +#if ZEN_PLATFORM_LINUX +# include <spawn.h> +#endif + #include <fmt/format.h> ZEN_THIRD_PARTY_INCLUDES_END @@ -1070,6 +1074,114 @@ CreateProc(const std::filesystem::path& Executable, std::string_view CommandLine } return CreateProcNormal(Executable, CommandLine, Options); +#elif ZEN_PLATFORM_LINUX + // posix_spawn uses CLONE_VM|CLONE_VFORK internally and does not copy the parent's + // virtual address space, preventing ENOMEM from fork() on systems where strict overcommit + // is disabled (vm.overcommit_memory=2) or a per-process RLIMIT_AS limit is enforced. + // Requires glibc >= 2.29 for posix_spawn_file_actions_addchdir_np. + std::vector<char*> ArgV; + std::string CommandLineZ(CommandLine); + BuildArgV(ArgV, CommandLineZ.data()); + ArgV.push_back(nullptr); + + posix_spawn_file_actions_t FileActions; + posix_spawnattr_t Attr; + + int Err = posix_spawn_file_actions_init(&FileActions); + if (Err != 0) + { + ThrowSystemError(Err, "posix_spawn_file_actions_init failed"); + } + auto FileActionsGuard = MakeGuard([&] { posix_spawn_file_actions_destroy(&FileActions); }); + + Err = posix_spawnattr_init(&Attr); + if (Err != 0) + { + ThrowSystemError(Err, "posix_spawnattr_init failed"); + } + auto AttrGuard = MakeGuard([&] { posix_spawnattr_destroy(&Attr); }); + + if (Options.WorkingDirectory != nullptr) + { + Err = posix_spawn_file_actions_addchdir_np(&FileActions, Options.WorkingDirectory->c_str()); + if (Err != 0) + { + ThrowSystemError(Err, "posix_spawn_file_actions_addchdir_np failed"); + } + } + + if (Options.StdoutPipe != nullptr && Options.StdoutPipe->WriteFd >= 0) + { + const int StdoutWriteFd = Options.StdoutPipe->WriteFd; + ZEN_ASSERT(StdoutWriteFd > STDERR_FILENO); + posix_spawn_file_actions_adddup2(&FileActions, StdoutWriteFd, STDOUT_FILENO); + + if (Options.StderrPipe != nullptr && Options.StderrPipe->WriteFd >= 0) + { + const int StderrWriteFd = Options.StderrPipe->WriteFd; + ZEN_ASSERT(StderrWriteFd > STDERR_FILENO && StderrWriteFd != StdoutWriteFd); + posix_spawn_file_actions_adddup2(&FileActions, StderrWriteFd, STDERR_FILENO); + posix_spawn_file_actions_addclose(&FileActions, StderrWriteFd); + } + else + { + posix_spawn_file_actions_adddup2(&FileActions, StdoutWriteFd, STDERR_FILENO); + } + + posix_spawn_file_actions_addclose(&FileActions, StdoutWriteFd); + } + else if (!Options.StdoutFile.empty()) + { + posix_spawn_file_actions_addopen(&FileActions, STDOUT_FILENO, Options.StdoutFile.c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0644); + posix_spawn_file_actions_adddup2(&FileActions, STDOUT_FILENO, STDERR_FILENO); + } + + if (Options.ProcessGroupId > 0) + { + posix_spawnattr_setflags(&Attr, POSIX_SPAWN_SETPGROUP); + posix_spawnattr_setpgroup(&Attr, Options.ProcessGroupId); + } + + // Build custom envp if overrides are specified; otherwise inherit parent environment unchanged. + char** Envp = environ; + std::vector<std::string> EnvStrings; + std::vector<char*> EnvPtrs; + if (!Options.Environment.empty()) + { + std::map<std::string, std::string> EnvMap; + for (char** E = environ; *E; ++E) + { + std::string_view Entry(*E); + const size_t EqPos = Entry.find('='); + if (EqPos != std::string_view::npos) + { + EnvMap[std::string(Entry.substr(0, EqPos))] = std::string(Entry.substr(EqPos + 1)); + } + } + for (const auto& [Key, Value] : Options.Environment) + { + EnvMap[Key] = Value; + } + for (const auto& [Key, Value] : EnvMap) + { + EnvStrings.push_back(Key + "=" + Value); + } + for (std::string& S : EnvStrings) + { + EnvPtrs.push_back(S.data()); + } + EnvPtrs.push_back(nullptr); + Envp = EnvPtrs.data(); + } + + pid_t ChildPid = 0; + Err = posix_spawn(&ChildPid, Executable.c_str(), &FileActions, &Attr, ArgV.data(), Envp); + if (Err != 0) + { + ThrowSystemError(Err, "Failed to posix_spawn a new child process"); + } + + return int(ChildPid); #else std::vector<char*> ArgV; std::string CommandLineZ(CommandLine); |