From 8d9687f76fc0dcc4d09088eaffca045d1964451e Mon Sep 17 00:00:00 2001
From: dragonmuffin <dragonmuffin@dragonmuffin>
Date: Mon, 23 Sep 2024 22:52:43 +0500
Subject: [PATCH] prettify code

---
 starter/ns_exec.c | 46 +++++++++++++++++------------------
 starter/starter.c | 62 ++++++++++++++++++++++++-----------------------
 2 files changed, 54 insertions(+), 54 deletions(-)

diff --git a/starter/ns_exec.c b/starter/ns_exec.c
index 8503837..08eedc0 100644
--- a/starter/ns_exec.c
+++ b/starter/ns_exec.c
@@ -12,14 +12,14 @@ static void procfs_prepare()
 
 #define put_old "oldfs"
 void mnt_prepare(char* rootfs, char* shared_mountpoint) {
-    char* shared_folder=NULL;
-    asprintf(&shared_folder,"../%s",shared_mountpoint);
-    if (mount(rootfs,rootfs,"ext4",MS_BIND,""))                                     die("failed to mount %s: %m", rootfs);
+    char* shared_folder = NULL;
+    asprintf(&shared_folder, "../%s", shared_mountpoint);
+    if (mount(rootfs, rootfs, "ext4", MS_BIND,""))                                  die("failed to mount %s: %m", rootfs);
     if (chdir(rootfs))                                                              die("falied to cd:%m");
     //if (mount("/sys","sys","sysfs",0,""))                                         die("failed to mount sysfs: %m");
     //if (mount("/dev","dev","udev",0,""))                                          die("failed to mount: %m");
     if (mkdir("shared", 0777) && errno != EEXIST)                                   die("Failed to mkdir %s: %m\n", shared_mountpoint);
-    if (mount(shared_folder,"shared","ext4",MS_BIND,""))                            die("failed to mount shared folder: %m");
+    if (mount(shared_folder, "shared", "ext4", MS_BIND, ""))                        die("failed to mount shared folder: %m");
     if (mkdir(put_old, 0000) && errno != EEXIST)                                    die("Failed to mkdir %s: %m\n", put_old);
     if (syscall(SYS_pivot_root, ".", put_old))                                      die("Failed to pivot_root from %s to %s: %m\n", rootfs, put_old);
     if (chdir("/"))                                                                 die("Failed to chdir to new root: %m\n");
@@ -30,14 +30,12 @@ void mnt_prepare(char* rootfs, char* shared_mountpoint) {
 }
 void ro_fs(char* shared_mountpoint) {
     char* shared_folder = malloc(strlen(shared_mountpoint)+4);
-    strcpy(shared_folder,"../");
-    strcat(shared_folder,shared_mountpoint);
-    if (mount("/","/","ext4",MS_REMOUNT | MS_RDONLY| MS_BIND,""))                  die("failed to mount: %m");
-    if (mount(shared_mountpoint,"shared","ext4",MS_REMOUNT | MS_BIND,""))  die("failed to mount: %m");
+    strcpy(shared_folder, "../");
+    strcat(shared_folder, shared_mountpoint);
+    if (mount("/", "/", "ext4", MS_REMOUNT | MS_RDONLY| MS_BIND, ""))               die("failed to mount: %m");
+    if (mount(shared_mountpoint, "shared", "ext4", MS_REMOUNT | MS_BIND, ""))       die("failed to mount: %m");
     free(shared_folder);
 }
-//#undef shared_mountpoint
-//#undef shared_folder
 #undef put_old
 
 void await_setup(int pipe) { // wait for signal from parent
@@ -51,20 +49,20 @@ static int nsrun(void* arg) {
     struct params *params = (struct params*) arg;
     await_setup(params->fd[0]);
     char cwd[PATH_MAX];
-    if(getcwd(cwd,sizeof(cwd))==NULL) die("getcwd error: %m");
+    if(getcwd(cwd, sizeof(cwd))==NULL) die("getcwd error: %m");
     if(chdir(params->shared_folder)) die("failed to chdir to shared folder: %m")
-    int out_fd=open("out",O_WRONLY|O_CREAT,0666);
-    if(out_fd==-1) die("unable to open output file:%m")
-    else dup2(out_fd,STDOUT_FILENO);
-    int in_fd=open("in",O_RDONLY|O_CREAT,0666);
-    if(in_fd==-1) die("unable to open input file:%m")
-    else dup2(in_fd,STDIN_FILENO);
-    int err_fd=open("err",O_WRONLY|O_CREAT,0666);
-    if(err_fd==-1) die("unable to open error file:%m")
-    else dup2(err_fd,STDERR_FILENO);
+    int out_fd = open("out", O_WRONLY | O_CREAT, 0666);
+    if(out_fd == -1) die("unable to open output file:%m")
+    else dup2(out_fd, STDOUT_FILENO);
+    int in_fd = open("in", O_RDONLY | O_CREAT, 0666);
+    if(in_fd == -1) die("unable to open input file:%m")
+    else dup2(in_fd, STDIN_FILENO);
+    int err_fd = open("err", O_WRONLY | O_CREAT, 0666);
+    if(err_fd == -1) die("unable to open error file:%m")
+    else dup2(err_fd, STDERR_FILENO);
     if(chdir(cwd)) die("failed to chdir: %m");
-    mnt_prepare("minrootfs",params->shared_folder);
-    sethostname(hostname,sizeof(hostname));
+    mnt_prepare("minrootfs", params->shared_folder);
+    sethostname(hostname, sizeof(hostname));
     ro_fs(params->shared_folder);
     if(setgid(1000)) die("failed to setgid:%m");
     if(setuid(1000)) die("failed to setuid:%m");
@@ -75,6 +73,6 @@ static int nsrun(void* arg) {
         "PWD=/",
         NULL,
     };
-    if (execve(cmd,argv,env) == -1) die("failed to exec,%m");
-    return 1;
+    if (execve(cmd, argv, env) == -1) die("failed to exec,%m");
+    return 1;// removes warning
 }
diff --git a/starter/starter.c b/starter/starter.c
index d1ece92..6b022b7 100644
--- a/starter/starter.c
+++ b/starter/starter.c
@@ -39,19 +39,18 @@ struct killparams{
 #include "ns_exec.c"
 #include "cgroup_prepare.c"
 
-//bool TL_achieve=false;
 uint64_t time_start;
 
-//get time in milliseconds
+// get time in milliseconds
 uint64_t getmstime() {
     struct timeval tm;
-    gettimeofday(&tm,NULL);
-    return (uint64_t)tm.tv_sec*1000+(uint64_t)tm.tv_usec/1000;
+    gettimeofday(&tm, NULL);
+    return (uint64_t) tm.tv_sec * 1000 + (uint64_t) tm.tv_usec / 1000;
 }
 
-//time limit realisation
+// time limit realisation
 static int killafter(void *arg) {
-    //die when parent dies
+    // die when parent dies
     if (prctl(PR_SET_PDEATHSIG, SIGKILL)) die("cannot PR_SET_PDEATHSIG for child process: %m\n");
     struct killparams* params = (struct killparams*) arg;
     struct timespec tw = {params -> time / 1000, ((params->time) % 1000+5) * 1000000};
@@ -65,7 +64,7 @@ static int killafter(void *arg) {
 static char nmstack[STACK_SIZE];
 static char killstack[STACK_SIZE];
 
-static void parse_args(int argc, char **argv, struct params *params,struct limits *limits){
+static void parse_args(int argc, char **argv, struct params *params, struct limits *limits){
     if (argc < 7) {
         puts("usage:\n starter <max processes number> <core_id> <memory_amount> <time limit in ms> <shared folder> <command, arg1,arg2,...>");
         exit(0);
@@ -85,18 +84,18 @@ static void parse_args(int argc, char **argv, struct params *params,struct limit
     params->argv = argv;
 }
 
-//setup user namespace
+// setup user namespace
 static void prepare_userns(int pid) {
     char path[100];
     char line[100];
 
-    int uid = 0;//root
-    int gid = 0;//root
-    int unprivileged_uid = 66534;//nobody
-    int unprivileged_gid = 65534;//nogroup
+    int uid = 0;// root
+    int gid = 0;// root
+    int unprivileged_uid = 66534;// nobody
+    int unprivileged_gid = 65534;// nogroup
 
     sprintf(path, "/proc/%d/uid_map", pid);
-    sprintf(line, "0 %d 1\n1 %d 1000\n", uid, unprivileged_uid);//map root to uid 0,nobody to uid 1000
+    sprintf(line, "0 %d 1\n1 %d 1000\n", uid, unprivileged_uid);// map root to uid 0,nobody to unprivileged uid
     write_file(path, line);
 
     sprintf(path, "/proc/%d/setgroups", pid);
@@ -104,45 +103,48 @@ static void prepare_userns(int pid) {
     write_file(path, line);
 
     sprintf(path, "/proc/%d/gid_map", pid);
-    sprintf(line, "0 %d 1\n1 %d 1000\n", gid, unprivileged_gid);//map root to gid 0,nogroup to gid 1000
+    sprintf(line, "0 %d 1\n1 %d 1000\n", gid, unprivileged_gid);// map root to gid 0,nogroup to unprivileged gid
     write_file(path, line);
 }
 
+static void get_real_path(char* path) {
+    if (realpath (argv[0], path) == 0) die("unable to resolve real path: %m");// get absolute path to executable
+    for(int i = strlen(path); i > 0 && path[i] != '/';i--) path[i]=0;// cut filename to get directory name
+}
+
 int main(int argc,char** argv) {
-    if(setuid(0)) die("need to be run as root");
-    if(setgid(0)) die("need to be run as root");
-    //get binary folder
-    char bin_path[PATH_MAX];
-    if (realpath (argv[0], bin_path) == 0) die("unable to resolve real path: %m");//get absolute path to executable
-    for(int i = strlen(bin_path); i > 0 && bin_path[i] != '/';i--) bin_path[i]=0;//cut filename to get directory name
-    if(chdir(bin_path)) die("unable to chdir to binary path: %m");
-    //set random seed
+    if(setuid(0)) die("must be run as root");
+    if(setgid(0)) die("must be run as root");
+    // get binary path
+    char real_path[PATH_MAX];
+    get_real_path(real_path);
+    if(chdir(real_path)) die("unable to chdir to binary path: %m");
+    // set random seed
     srand(time(NULL));
-    //setup parameters
+    // setup parameters
     struct params params;
     memset(&params, 0, sizeof(struct params));
     struct limits limits;
     memset(&limits, 0, sizeof(struct limits));
     parse_args(argc, argv, &params, &limits);
     prepare_cgroup(&limits);
-    if (pipe(params.fd) < 0) die("can't open pipe: %m");//a pipe to report readiness
+    if (pipe(params.fd) < 0) die("can't open pipe: %m");// a pipe to report readiness
     int clone_flags = SIGCHLD | CLONE_NEWUTS | CLONE_NEWUSER | CLONE_NEWNS | CLONE_NEWPID | CLONE_NEWNET | CLONE_NEWIPC | CLONE_NEWCGROUP;
-    int nsrun_pid = clone(nsrun, nmstack + STACK_SIZE, clone_flags, &params);//make new namespace
-    //int pipe = params.fd[1];
+    int nsrun_pid = clone(nsrun, nmstack + STACK_SIZE, clone_flags, &params);// make new namespace
     prepare_userns(nsrun_pid);
     if (nsrun_pid < 0) die("faled to clone");
     add_to_cgroup(nsrun_pid);
-    if (write(params.fd[1], "OK", 2) != 2) die("Failed to write to pipe: %m");//report readiness
+    if (write(params.fd[1], "OK", 2) != 2) die("Failed to write to pipe: %m");// report readiness
     struct killparams killparams;
     killparams.time = limits.time;
     killparams.pid = nsrun_pid;
     int kill_pid = clone(killafter, killstack + STACK_SIZE, SIGCHLD, &killparams);
     time_start = getmstime();
     if (waitpid(nsrun_pid, NULL, 0) == -1) die("Failed to wait pid %d: %m\n", nsrun_pid);
-    kill(kill_pid,SIGKILL);//kill killer
-    int time = getmstime()-time_start;
+    kill(kill_pid, SIGKILL);// kill killer
+    int time = getmstime() - time_start;
     if(chdir(params.shared_folder)) die("Failed to chdir to shared folder:%m");
-    if(time>=limits.time) {
+    if(time >= limits.time) {
         write_file("time", "-1");
     }
     else {