From 7891f4f491873e9063c02d4d4fafbd51242b4a43 Mon Sep 17 00:00:00 2001
From: cbdev <cb@cbcdn.com>
Date: Mon, 3 Jul 2023 23:44:58 +0200
Subject: Implement child stop

---
 command.c     | 57 ++++++++++++++++++++++++++++++++++++++++++++-------------
 commander.cfg |  3 ++-
 2 files changed, 46 insertions(+), 14 deletions(-)

diff --git a/command.c b/command.c
index 305664b..12e24c6 100644
--- a/command.c
+++ b/command.c
@@ -4,6 +4,7 @@
 #include <unistd.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <signal.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 
@@ -26,6 +27,8 @@ typedef struct {
 static size_t ncommands = 0;
 static command_t* commands = NULL;
 
+//TODO timeouting / SIGKILL
+
 int command_handle(int fd){
 	size_t n = 0;
 	ssize_t bytes;
@@ -35,7 +38,7 @@ int command_handle(int fd){
 	for(n = 0; n < ncommands; n++){
 		if(commands[n].flags & COMMAND_ALIVE
 				&& fd == commands[n].iopipe[0]){
-			bytes = read(fd, input_buffer, sizeof(input_buffer));
+			bytes = read(fd, input_buffer, sizeof(input_buffer) - 1);
 			if(bytes < 0){
 				perror("cmd/recv");
 			}
@@ -47,6 +50,7 @@ int command_handle(int fd){
 			}
 			else{
 				//TODO handle
+				input_buffer[bytes] = 0;
 				printf("%d bytes from command %lu: %s\n", bytes, n, input_buffer);
 			}
 			return 0;
@@ -77,8 +81,11 @@ void command_reap(){
 				if(commands[n].child == status){
 					commands[n].flags = 0;
 					commands[n].child = -1;
-					close(commands[n].iopipe[0]);
-					commands[n].iopipe[0] = -1;
+					if(commands[n].iopipe[0] >= 0){
+						core_manage_fd(commands[n].iopipe[0], 0, system_command);
+						close(commands[n].iopipe[0]);
+						commands[n].iopipe[0] = -1;
+					}
 					printf("Command %lu terminated\n", n);
 				}
 			}
@@ -112,12 +119,24 @@ static int command_spawn(command_t* cmd, char* command_name, char* command_stati
 				_exit(1);
 			}
 
+			//make child a session leader
+			setpgrp();
+
 			//connect stdout
 			while((dup2(cmd->iopipe[1], STDOUT_FILENO) == -1) && (errno == EINTR)) {
 			}
 			close(cmd->iopipe[1]);
-			execl(command_name, command_static, NULL);
-			perror("cmd/exec");
+
+			//TODO set environment
+
+			//run actual command
+			if(handler){
+				execl(handler, handler, command_name, command_static, NULL);
+			}
+			else{
+				execl(command_name, command_name, command_static, NULL);
+			}
+			perror("child/exec");
 			_exit(1);
 		default:
 			//parent
@@ -169,6 +188,12 @@ int command_start(nfc_tag_info_t* info){
 			break;
 		}
 	}
+
+	if(!strlen((char*) command_name)){
+		printf("Tag contains invalid command data\n");
+		free(command_name);
+		return 1;
+	}
 	//FIXME might want to parse out any non-graphs
 
 	if(p == ncommands){
@@ -176,7 +201,8 @@ int command_start(nfc_tag_info_t* info){
 		if(!commands){
 			ncommands = 0;
 			printf("Failed to allocate memory\n");
-			goto bail;
+			free(command_name);
+			return 1;
 		}
 		memset(commands + p, 0, sizeof(command_t));
 		ncommands++;
@@ -187,11 +213,18 @@ int command_start(nfc_tag_info_t* info){
 		//TODO clean up and free command instance
 	}
 
-bail:
 	free(command_name);
 	return 0;
 }
 
+static void command_stop_internal(size_t n){
+	//send SIGTERM to process group
+	if(kill(-commands[n].child, (commands[n].flags & COMMAND_STOPPED) ? SIGKILL : SIGTERM)){
+		perror("cmd/stop");
+	}
+	commands[n].flags |= COMMAND_STOPPED;
+}
+
 int command_stop(nfc_tag_info_t* info){
 	size_t n = 0;
 
@@ -199,8 +232,7 @@ int command_stop(nfc_tag_info_t* info){
 		if(commands[n].tag == info){
 			commands[n].tag = NULL;
 			if(commands[n].flags & COMMAND_ALIVE){
-				//TODO stop running command
-				commands[n].flags |= COMMAND_STOPPED;
+				command_stop_internal(n);
 			}
 		}
 	}
@@ -213,11 +245,10 @@ void command_free(){
 
 	printf("Shutting down any remaining commands\n");
 	for(n = 0; n < ncommands; n++){
-		if(commands[n].flags & COMMAND_ALIVE){
-			//TODO stop command, terminate command
+		while(commands[n].flags & COMMAND_ALIVE){
+			command_stop_internal(n);
+			command_reap();
 		}
-
-		//TODO free allocated data
 	}
 
 	ncommands = 0;
diff --git a/commander.cfg b/commander.cfg
index 87b5940..b32a064 100644
--- a/commander.cfg
+++ b/commander.cfg
@@ -11,4 +11,5 @@ bind = 0.0.0.0 7812
 [command]
 ;commanddir = commands
 chdir = commands/
-handler = handle_tag
+;handler = handle_tag
+
-- 
cgit v1.2.3