# Standard input and output can be handled through streams.
module exec
-import stream
+import file
+
+in "C" `{
+ #include <stdlib.h>
+ #include <string.h>
+ #include <errno.h>
+ #include <stdio.h>
+ #include <unistd.h>
+ #include <sys/wait.h>
+ #include <signal.h>
+`}
+
+in "C Header" `{
+ #include <sys/types.h>
+
+ // FIXME this should be in the "C" block when bug on module blocks is fixed
+ // or, even better, replace the C structure by a Nit object.
+ typedef struct se_exec_data se_exec_data_t;
+ struct se_exec_data {
+ pid_t id;
+ int running;
+ int status;
+ int in_fd;
+ int out_fd;
+ int err_fd;
+ };
+`}
# Simple sub-process
class Process
var arguments: nullable Array[String]
# Launch a command with some arguments
- init(command: String, arguments: String...)
- do
+ init(command: String, arguments: String...) is old_style_init do
self.command = command
self.arguments = arguments
execute
end
private var data: NativeProcess
- private fun basic_exec_execute(p: NativeString, av: NativeString, ac: Int, pf: Int): NativeProcess is extern "exec_Process_Process_basic_exec_execute_4"
+ private fun basic_exec_execute(prog, args: NativeString, argc: Int, pipeflag: Int): NativeProcess `{
+ se_exec_data_t* result = NULL;
+ int id;
+ int in_fd[2];
+ int out_fd[2];
+ int err_fd[2];
+ if (pipeflag & 1) {
+ int res = pipe(in_fd);
+ if ( res == -1 ) {
+ return NULL;
+ }
+ }
+ if (pipeflag & 2) {
+ int res = pipe(out_fd);
+ if ( res == -1 ) {
+ return NULL;
+ }
+ }
+ if (pipeflag & 4) {
+ int res = pipe(err_fd);
+ if ( res == -1 ) {
+ return NULL;
+ }
+ }
+
+ id = fork();
+ if (id == 0)
+ { /* child */
+ char **arg = malloc(sizeof(char*) * (argc+1));
+ char *c = args;
+ int i;
+
+ /* Prepare args */
+ for(i=0; i<argc; i++)
+ {
+ arg[i] = c;
+ c += strlen(c) + 1;
+ }
+ arg[argc] = NULL;
+
+ /* Connect pipe */
+ if (pipeflag & 1)
+ {
+ close(0);
+ dup2(in_fd[0], 0);
+ close(in_fd[0]);
+ close(in_fd[1]);
+ }
+ if (pipeflag & 2)
+ {
+ close(1);
+ dup2(out_fd[1], 1);
+ close(out_fd[0]);
+ close(out_fd[1]);
+ }
+ if (pipeflag & 4)
+ {
+ close(2);
+ dup2(err_fd[1], 2);
+ close(err_fd[0]);
+ close(err_fd[1]);
+ }
+
+ /* calls */
+ execvp(prog, arg);
+ _exit(127);
+ }
+ else if (id > 0)
+ { /* father */
+ result = (se_exec_data_t*)malloc(sizeof(se_exec_data_t));
+ result->id = id;
+ result->running = 1;
+ if (pipeflag & 1)
+ {
+ result->in_fd = in_fd[1];
+ close(in_fd[0]);
+ } else
+ result->in_fd = -1;
+
+ if (pipeflag & 2)
+ {
+ result->out_fd = out_fd[0];
+ close(out_fd[1]);
+ } else
+ result->out_fd = -1;
+
+ if (pipeflag & 4)
+ {
+ result->err_fd = err_fd[0];
+ close(err_fd[1]);
+ } else
+ result->err_fd = -1;
+ }
+
+ return result;
+ `}
end
-# stdout of the process is readable
-class IProcess
+# `Process` on which the `stdout` is readable like a `Reader`
+class ProcessReader
super Process
- super IStream
- var stream_in: FDIStream
+ super Reader
+
+ # File Descriptor used for the input.
+ var stream_in: FileReader is noinit
redef fun close do stream_in.close
redef fun read_char do return stream_in.read_char
+ redef fun read_byte do return stream_in.read_byte
+
redef fun eof do return stream_in.eof
redef fun pipeflags do return 2
- redef init(command: String, arguments: String...) do super
-
redef fun execute
do
super
- stream_in = new FDIStream(data.out_fd)
+ stream_in = new FileReader.from_fd(data.out_fd)
end
end
-# stdin of the process is writable
-class OProcess
+# `Process` on which `stdin` is writable like a `Writer`
+class ProcessWriter
super Process
- super OStream
- var stream_out: OStream
+ super Writer
+
+ # File Descriptor used for the output.
+ var stream_out: Writer is noinit
redef fun close do stream_out.close
redef fun pipeflags do return 1
- redef init(command: String, arguments: String...) do super
-
redef fun execute
do
super
- stream_out = new FDOStream(data.in_fd)
+ var out = new FileWriter.from_fd(data.in_fd)
+ out.set_buffering_mode(0, sys.buffer_mode_none)
+ stream_out = out
end
end
-# stdin and stdout are both accessible
-class IOProcess
- super IProcess
- super OProcess
- super IOStream
+# `Process` on which stdout can be read and stdin can be written to like a `Duplex`
+class ProcessDuplex
+ super ProcessReader
+ super ProcessWriter
+ super Duplex
redef fun close
do
redef fun pipeflags do return 3
- redef init(command: String, arguments: String...) do super
-
- redef fun execute
+ redef fun execute do super
+
+ # Write `input` to process and return its output
+ #
+ # Writing and reading are processed line by line,
+ # reading only when something is available.
+ #
+ # ~~~
+ # var proc = new ProcessDuplex("tr", "[:lower:]", "[:upper:]")
+ # assert proc.write_and_read("""
+ # Alice
+ # Bob
+ # """) == """
+ # ALICE
+ # BOB
+ # """
+ # ~~~
+ fun write_and_read(input: Text): String
do
- super
+ var read = new Buffer #new Array[String]
+
+ # Main loop, read and write line by line
+ var prev = 0
+ for delimiter in input.search_all('\n') do
+ write input.substring(prev, delimiter.after-prev)
+ prev = delimiter.after
+
+ while stream_in.poll_in do
+ read.append stream_in.read_line
+ end
+ end
+
+ # Write the last line
+ write input.substring_from(prev)
+ stream_out.close
+
+ # Read the rest, may be everything for some programs
+ read.append stream_in.read_all
+ stream_in.close
+
+ # Clean up
+ wait
+ return read.to_s
end
end
end
redef class NativeString
- fun system: Int is extern "string_NativeString_NativeString_system_0"
+ # Execute self as a shell command.
+ #
+ # See the posix function system(3).
+ fun system: Int `{
+ int status = system(self);
+ if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) {
+ // system exited on SIGINT: in my opinion the user wants the main to be discontinued
+ kill(getpid(), SIGINT);
+ }
+ return status;
+ `}
end
-private extern class NativeProcess
- fun id: Int is extern "exec_NativeProcess_NativeProcess_id_0"
- fun is_finished: Bool is extern "exec_NativeProcess_NativeProcess_is_finished_0"
- fun status: Int is extern "exec_NativeProcess_NativeProcess_status_0"
- fun wait is extern "exec_NativeProcess_NativeProcess_wait_0"
-
- fun in_fd: Int is extern "exec_NativeProcess_NativeProcess_in_fd_0"
- fun out_fd: Int is extern "exec_NativeProcess_NativeProcess_out_fd_0"
- fun err_fd: Int is extern "exec_NativeProcess_NativeProcess_err_fd_0"
+private extern class NativeProcess `{ se_exec_data_t* `}
+
+ fun id: Int `{ return self->id; `}
+ fun status: Int `{ return self->status; `}
+ fun in_fd: Int `{ return self->in_fd; `}
+ fun out_fd: Int `{ return self->out_fd; `}
+ fun err_fd: Int `{ return self->err_fd; `}
+
+ fun is_finished: Bool `{
+ int result = (int)0;
+ int status;
+ if (self->running) {
+ int id = waitpid(self->id, &status, WNOHANG);
+ if (id != 0) {
+ /* child is finished */
+ result = (int)(id == self->id);
+ self->status = WEXITSTATUS(status);
+ self->running = 0;
+ }
+ }
+ else{
+ result = (int)1;
+ }
+ return result;
+ `}
+
+ fun wait `{
+ int status;
+ if (self->running) {
+ waitpid(self->id, &status, 0);
+ self->status = WEXITSTATUS(status);
+ self->running = 0;
+ }
+ `}
end