Initial project import

tools/v/vlib/os/process.v

@@ -0,0 +1,79 @@
+module os
+
+// - ProcessState.not_started - the process has not yet started
+// - ProcessState.running - the process is currently running
+// - ProcessState.stopped - the process was running, but was stopped temporarily
+// - ProcessState.exited - the process has finished/exited
+// - ProcessState.aborted - the process was terminated by a signal
+// - ProcessState.closed - the process resources like opened file descriptors were freed/discarded, final state.
+pub enum ProcessState {
+	not_started
+	running
+	stopped
+	exited
+	aborted
+	closed
+}
+
+@[heap]
+pub struct Process {
+pub mut:
+	filename         string // the process's command file path
+	pid              int    // the PID of the process
+	code             int          = -1           // the exit code of the process, != -1 *only* when status is .exited *and* the process was not aborted
+	status           ProcessState = .not_started // the current status of the process
+	err              string   // if the process fails, contains the reason why
+	args             []string // the arguments that the command takes
+	work_folder      string   // the initial working folder of the process. When '', reuse the same folder as the parent process.
+	env_is_custom    bool     // true, when the environment was customized with .set_environment
+	env              []string // the environment with which the process was started  (list of 'var=val')
+	use_stdio_ctl    bool     // when true, then you can use p.stdin_write(), p.stdout_slurp() and p.stderr_slurp()
+	use_pgroup       bool     // when true, the process will create a new process group, enabling .signal_pgkill()
+	stdio_fd         [3]int   // the stdio file descriptors for the child process, used only by the nix implementation
+	wdata            voidptr  // the WProcess; used only by the windows implementation
+	create_no_window bool     // sets a value indicating whether to start the process in a new window, The default is false; used only by the windows implementation
+}
+
+// new_process - create a new process descriptor.
+// Note: new does NOT start the new process.
+// That is done because you may want to customize it first,
+// by calling different set_ methods on it.
+// In order to start it, call p.run() or p.wait()
+pub fn new_process(filename string) &Process {
+	return &Process{
+		filename: filename
+		stdio_fd: [-1, -1, -1]!
+	}
+}
+
+// set_args - set the arguments for the new process.
+pub fn (mut p Process) set_args(pargs []string) {
+	if p.status != .not_started {
+		return
+	}
+	p.args = pargs
+	return
+}
+
+// set_work_folder - set the initial working folder for the new process.
+// If you do not set it, it will reuse the current working folder of the parent process.
+pub fn (mut p Process) set_work_folder(path string) {
+	if p.status != .not_started {
+		return
+	}
+	p.work_folder = real_path(path)
+	return
+}
+
+// set_environment - set a custom environment variable mapping for the new process.
+pub fn (mut p Process) set_environment(envs map[string]string) {
+	if p.status != .not_started {
+		return
+	}
+	p.env_is_custom = true
+	p.env = []string{}
+	for k, v in envs {
+		p.env << '${k}=${v}'
+	}
+	return
+}