The branch main has been updated by kevans:
URL:
https://cgit.FreeBSD.org/src/commit/?id=6a2c624b35a0c760b00b9a34c10b7ea0c240c677
commit 6a2c624b35a0c760b00b9a34c10b7ea0c240c677
Author: Kyle Evans <kev...@freebsd.org>
AuthorDate: 2025-07-09 05:12:31 +0000
Commit: Kyle Evans <kev...@freebsd.org>
CommitDate: 2025-07-09 05:12:31 +0000
flua: fbsd: return a process handle to operate on when we exec()
This gives us some way to be able to write to stdin if we want to, or
as a future improvement, will allow us to extract stdout from the
process. The handle is setup to close and waitpid() on close/gc so that
existing users wouldn't necessarily leak for the lifetime of the script
if they weren't adopted to the new model.
Reviewed by: bapt
Differential Revision: https://reviews.freebsd.org/D50538
---
libexec/flua/modules/lfbsd.c | 94 ++++++++++++++++++++++++++++++++++++++++----
1 file changed, 86 insertions(+), 8 deletions(-)
diff --git a/libexec/flua/modules/lfbsd.c b/libexec/flua/modules/lfbsd.c
index 6279474f8388..a361fa25601b 100644
--- a/libexec/flua/modules/lfbsd.c
+++ b/libexec/flua/modules/lfbsd.c
@@ -2,6 +2,7 @@
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright 2023 Baptiste Daroussin <b...@freebsd.org>
+ * Copyright (C) 2025 Kyle Evans <kev...@freebsd.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing that the following conditions~
@@ -38,6 +39,13 @@
#include "lauxlib.h"
#include "lfbsd.h"
+#define FBSD_PROCESSHANDLE "fbsd_process_t*"
+
+struct fbsd_process {
+ int pid;
+ int stdin_fileno;
+};
+
extern char **environ;
static const char**
@@ -65,7 +73,8 @@ luaL_checkarraystrings(lua_State *L, int arg)
static int
lua_exec(lua_State *L)
{
- int r, pstat;
+ struct fbsd_process *proc;
+ int r;
posix_spawn_file_actions_t action;
int stdin_pipe[2] = {-1, -1};
pid_t pid;
@@ -81,6 +90,9 @@ lua_exec(lua_State *L)
return (3);
}
+ proc = lua_newuserdata(L, sizeof(*proc));
+ proc->stdin_fileno = stdin_pipe[1];
+
posix_spawn_file_actions_init(&action);
posix_spawn_file_actions_adddup2(&action, stdin_pipe[0], STDIN_FILENO);
posix_spawn_file_actions_addclose(&action, stdin_pipe[1]);
@@ -91,6 +103,7 @@ lua_exec(lua_State *L)
close(stdin_pipe[0]);
close(stdin_pipe[1]);
posix_spawn_file_actions_destroy(&action);
+ lua_pop(L, 2); /* Pop off the process handle and args. */
lua_pushnil(L);
lua_pushstring(L, strerror(r));
@@ -98,12 +111,26 @@ lua_exec(lua_State *L)
return (3);
}
+ lua_pop(L, 1);
+
close(stdin_pipe[0]);
posix_spawn_file_actions_destroy(&action);
- while (waitpid(pid, &pstat, 0) == -1) {
- if (errno != EINTR) {
- close(stdin_pipe[1]);
+ proc->pid = pid;
+ luaL_setmetatable(L, FBSD_PROCESSHANDLE);
+
+ return 1;
+}
+
+static int
+lua_process_close(lua_State *L)
+{
+ struct fbsd_process *proc;
+ int pstat, r;
+
+ proc = luaL_checkudata(L, 1, FBSD_PROCESSHANDLE);
+ while (waitpid(proc->pid, &pstat, 0) == -1) {
+ if ((r = errno) != EINTR) {
lua_pushnil(L);
lua_pushstring(L, strerror(r));
lua_pushinteger(L, r);
@@ -111,18 +138,60 @@ lua_exec(lua_State *L)
}
}
- if (WEXITSTATUS(pstat) != 0) {
+ if (!WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0) {
lua_pushnil(L);
lua_pushstring(L, "Abnormal termination");
+ return (2);
+ }
+
+ if (proc->stdin_fileno >= 0)
+ close(proc->stdin_fileno);
+ proc->stdin_fileno = -1;
+
+ lua_pushboolean(L, 1);
+ return 1;
+}
+
+static int
+lua_process_stdin(lua_State *L)
+{
+ struct fbsd_process *proc;
+ luaL_Stream *p;
+ FILE *fp;
+ int r;
+
+ proc = luaL_checkudata(L, 1, FBSD_PROCESSHANDLE);
+ fp = fdopen(proc->stdin_fileno, "w");
+ if (fp == NULL) {
+ r = errno;
+
+ lua_pushnil(L);
+ lua_pushstring(L, strerror(r));
lua_pushinteger(L, r);
return (3);
}
- close(stdin_pipe[1]);
- lua_pushinteger(L, pid);
- return 1;
+ p = lua_newuserdata(L, sizeof(*p));
+ p->closef = &lua_process_close;
+ p->f = fp;
+ luaL_setmetatable(L, LUA_FILEHANDLE);
+ return (1);
}
+#define PROCESS_SIMPLE(n) { #n, lua_process_ ## n }
+static const struct luaL_Reg fbsd_process[] = {
+ PROCESS_SIMPLE(close),
+ PROCESS_SIMPLE(stdin),
+ { NULL, NULL },
+};
+
+static const struct luaL_Reg fbsd_process_meta[] = {
+ { "__index", NULL },
+ { "__gc", lua_process_close },
+ { "__close", lua_process_close },
+ { NULL, NULL },
+};
+
#define REG_SIMPLE(n) { #n, lua_ ## n }
static const struct luaL_Reg fbsd_lib[] = {
REG_SIMPLE(exec),
@@ -134,5 +203,14 @@ int
luaopen_fbsd(lua_State *L)
{
luaL_newlib(L, fbsd_lib);
+
+ luaL_newmetatable(L, FBSD_PROCESSHANDLE);
+ luaL_setfuncs(L, fbsd_process_meta, 0);
+
+ luaL_newlibtable(L, fbsd_process);
+ luaL_setfuncs(L, fbsd_process, 0);
+ lua_setfield(L, -2, "__index");
+ lua_pop(L, 1);
+
return (1);
}
