int
fgcmd(int argc, char **argv)
{
struct job *jp;
int i;
int status;
nextopt("");
jp = getjob(*argptr, 0);
if (jp->jobctl == 0)
error("job not created under job control");
out1fmt("%s", jp->ps[0].cmd);
for (i = 1; i < jp->nprocs; i++)
out1fmt(" | %s", jp->ps[i].cmd );
out1c('\n');
flushall();
for (i = 0; i < jp->nprocs; i++)
if (tcsetpgrp(ttyfd, jp->ps[i].pid) != -1)
break;
if (i >= jp->nprocs) {
error("Cannot set tty process group (%s) at %d",
strerror(errno), __LINE__);
}
restartjob(jp);
INTOFF;
status = waitforjob(jp);
INTON;
return status;
}
int
jobscmd(int argc, char *argv[])
{
char *id;
int ch, sformat, lformat;
optind = optreset = 1;
opterr = 0;
sformat = lformat = 0;
while ((ch = getopt(argc, argv, "ls")) != -1) {
switch (ch) {
case 'l':
lformat = 1;
break;
case 's':
sformat = 1;
break;
case '?':
default:
error("unknown option: -%c", optopt);
}
}
argc -= optind;
argv += optind;
if (argc == 0)
showjobs(0, sformat, lformat);
else
while ((id = *argv++) != NULL)
showjob(getjob(id), 0, sformat, lformat);
return (0);
}
const std::vector<disque_job*>* disque::getjob(const char* name,
size_t timeout, size_t count)
{
std::vector<string> names;
names.push_back(name);
return getjob(names, timeout, count);
}
/*function used to run user command using execvp*/
void run(char *input,char *usrcmdargs[],int is_background){
int pid1;
pid1=fork();
struct job_t *tempjob_list;
if(pid1 == 0){
close(fdin);
close(fdout);
//execvp return -1 if command do not exist, if it is successful, it do not return any value
err=execvp(usrcmdargs[0],usrcmdargs);
printf("errno is %d\n", errno);
if(err == -1){
printf("command do not exist\n");
exit(EXIT_FAILURE);
}
exit(0);
}
else if(is_background != 0){
addjob(job_list,pid1,BKG,input);
tempjob_list=getjob(job_list,pid1);
printf("[%d] %d running in background\n",tempjob_list->jid,pid1);
}
else{
//addjob(job_list,pid1,FRG,input);
waitpid(pid1,&status, 0);
}
}
/* state change of children handled here */
static void sigchld_handler(int sig)
{
pid_t child_pid;
jobs **job;
int status;
/*
* There can be multiple SIGCHLD at once, not necessarily they will all be handled,
* so we reap all the children in non-blocking mode that takes care of the pending child
* whose SIGCHLD is not attended
*/
/* SIGCHLD should be blocked in critical section of modifying joblist */
/* thy shall NOT pass */
while ((child_pid = waitpid(-1, &status, WNOHANG|WUNTRACED|WCONTINUED)) > 0) {
if (WIFEXITED(status)) {
deljob(child_pid);
}
else if (WIFSIGNALED(status)) {
job = getjob(child_pid, 0);
if (NOTNULL(job)) {
shell_printf(SHELLPRINT_CHKSS | SHELLPRINT_CHKTERM,
TERMSTR_GREEN("SIGCHLD: ")"[%d] (%d) killed by signal %d\n",
(*job)->jid, (*job)->pid[0], WTERMSIG(status));
deljob(child_pid);
}
}
else if (WIFSTOPPED(status)) {
job = getjob(child_pid, 0);
if (NOTNULL(job)) {
(*job)->state = ST;
shell_printf(SHELLPRINT_CHKSS | SHELLPRINT_CHKTERM,
TERMSTR_GREEN("SIGCHLD : ")"[%d] (%d) stopped by signal %d\n",
(*job)->jid, (*job)->pid[0], WSTOPSIG(status));
}
}
else if (WIFCONTINUED(status)) {
job = getjob(child_pid, 0);
if (NOTNULL(job))
(*job)->state = BG;
}
}
/* thy shall pass */
}
pid_t
getjobpgrp(char *name)
{
struct job *jp;
jp = getjob(name);
return -jp->ps[0].pid;
}
int
waitcmd(int argc, char **argv)
{
struct job *job;
int status, retval;
struct job *jp;
nextopt("");
if (!*argptr) {
/* wait for all jobs */
jp = jobtab;
if (jobs_invalid)
return 0;
for (;;) {
if (jp >= jobtab + njobs) {
/* no running procs */
return 0;
}
if (!jp->used || jp->state != JOBRUNNING) {
jp++;
continue;
}
if (dowait(WBLOCK, NULL) == -1)
return 128 + SIGINT;
jp = jobtab;
}
}
retval = 127; /* XXXGCC: -Wuninitialized */
for (; *argptr; argptr++) {
job = getjob(*argptr, 1);
if (!job) {
retval = 127;
continue;
}
/* loop until process terminated or stopped */
while (job->state == JOBRUNNING) {
if (dowait(WBLOCK|WNOFREE, job) == -1)
return 128 + SIGINT;
}
status = job->ps[job->nprocs ? job->nprocs - 1 : 0].status;
if (WIFEXITED(status))
retval = WEXITSTATUS(status);
#if JOBS
else if (WIFSTOPPED(status))
retval = WSTOPSIG(status) + 128;
#endif
else {
/* XXX: limits number of signals */
retval = WTERMSIG(status) + 128;
}
if (!iflag)
freejob(job);
}
return retval;
}
int
getjobpgrp(const char *name)
{
struct job *jp;
jp = getjob(name, 1);
if (jp == 0)
return 0;
return -jp->ps[0].pid;
}
//function used to handle SIGCHILD and delete the job from job list
void handle_sigchild(int signo){
int status;
pid_t pid;
struct job_t *tempjob_list;
while((pid = waitpid(-1,&status,WNOHANG|WUNTRACED)) > 0){
if(WIFEXITED(status)){ //checks if child process is terminated normally
tempjob_list=getjob(job_list,pid);
printf("[%d] %d finished %s\n",tempjob_list->jid,tempjob_list->pid,tempjob_list->inputcmd);
deletejob(job_list,pid); //if child terminates normally, delete it from the jobs list
}
else if(WIFSIGNALED(status)){
deletejob(job_list,pid);
}
else if(WIFSTOPPED(status)){
tempjob_list=getjob(job_list,pid);
tempjob_list->state=STP;
}
}
}
int
jobidcmd(int argc __unused, char **argv)
{
struct job *jp;
int i;
jp = getjob(argv[1]);
for (i = 0 ; i < jp->nprocs ; ) {
out1fmt("%d", (int)jp->ps[i].pid);
out1c(++i < jp->nprocs? ' ' : '\n');
}
return 0;
}
int
waitcmd(int argc, char **argv)
{
struct job *job;
int status, retval;
struct job *jp;
if (argc > 1) {
job = getjob(argv[1]);
} else {
job = NULL;
}
/*
* Loop until a process is terminated or stopped, or a SIGINT is
* received.
*/
in_waitcmd++;
do {
if (job != NULL) {
if (job->state) {
status = job->ps[job->nprocs - 1].status;
if (WIFEXITED(status))
retval = WEXITSTATUS(status);
#if JOBS
else if (WIFSTOPPED(status))
retval = WSTOPSIG(status) + 128;
#endif
else
retval = WTERMSIG(status) + 128;
if (! iflag)
freejob(job);
in_waitcmd--;
return retval;
}
} else {
for (jp = jobtab ; ; jp++) {
if (jp >= jobtab + njobs) { /* no running procs */
in_waitcmd--;
return 0;
}
if (jp->used && jp->state == 0)
break;
}
}
} while (dowait(1, (struct job *)NULL) != -1);
in_waitcmd--;
return 0;
}
int
jobidcmd(int argc, char **argv)
{
struct job *jp;
int i;
nextopt("");
jp = getjob(*argptr, 0);
for (i = 0 ; i < jp->nprocs ; ) {
out1fmt("%ld", (long)jp->ps[i].pid);
out1c(++i < jp->nprocs ? ' ' : '\n');
}
return 0;
}
/* removes job from the joblist by pid,
* silently returns if job absent */
void deljob(pid_t pid)
{
jobs **job, *target;
job = getjob(pid, 0);
/* getjob can return (job **)NULL or &(job *)NULL */
if (NOTNULL(job)) {
target = *job;
/* order is IMPORTANT, we dont want to free neighbour's next
* so update neighbour first then kill the target */
*job = (*job)->next;
free(target);
}
}
/*
* builtin_command - if builtin, run it and return true
*/
int builtin_command(char **argv) {
char *cmd = argv[0];
/* jobs command */
if (!strcmp(cmd, "jobs")) {
listjobs(jobs);
return 1;
}
/* bg and fg commands */
if (!strcmp(cmd, "bg") || !strcmp(cmd, "fg")) {
int pid;
struct job_t *jobp;
/* ignore command if no argument */
if (argv[1] == NULL) {
printf("%s command needs PID argument\n", cmd);
return 1;
}
pid = atoi(argv[1]);
if ((jobp = getjob(jobs, pid)) != NULL) {
if (!strcmp(cmd, "bg")) {
Kill(pid, SIGCONT);
updatejob(jobs, pid, BG);
printf("%d %s", pid, jobs->cmdline);
}
if (!strcmp(cmd, "fg")) {
Kill(pid, SIGCONT);
updatejob(jobs, pid, FG);
waitfg(pid);
}
}
else
printf("Job %d not found\n", pid);
return 1;
}
/* ignore singleton & */
if (!strcmp(argv[0], "&")) {
return 1;
}
/* not a builtin command */
return 0;
}
int
bgcmd(int argc, char **argv)
{
struct job *jp;
do {
jp = getjob(*++argv);
if (jp->jobctl == 0)
error("job not created under job control");
if (jp->state == JOBDONE)
continue;
restartjob(jp);
jp->foreground = 0;
out1fmt("[%td] ", jp - jobtab + 1);
printjobcmd(jp);
} while (--argc > 1);
return 0;
}
/* what >bg and >fg run */
void do_bgfg(char **cmd, int state)
{
jobs **job;
sigset_t msk;
MASK_SIG(SIG_BLOCK, SIGCHLD, msk);
if (!cmd[1]) {
job = get_lastjob();
}
else if (*cmd[1]=='%' && atoi(cmd[1]+1)) {
job = getjob(0, atoi(cmd[1]+1));
}
else {
ERRMSG("Invalid argument\n");
return;
}
/* thy shall NOT pass */
if (NOTNULL(job)) {
(*job)->state = state;
if (kill(-(*job)->pid[0], SIGCONT) < 0)
ERR_EXIT("kill");
if (state == BG) {
shell_printf(SHELLPRINT_CHKSS | SHELLPRINT_CHKTERM,
"[%d] (%d) %s\n", (*job)->jid, (*job)->pid[0], (*job)->cmdline);
}
else {
shell_printf(SHELLPRINT_CHKSS | SHELLPRINT_CHKTERM,
"%s\n", (*job)->cmdline);
wait_fg(job);
}
}
else {
ERRMSG("Invalid job\n");
}
/* thy shall pass */
MASK_SIG(SIG_UNBLOCK, SIGCHLD, msk);
}
int
fgcmd(int argc __unused, char **argv)
{
struct job *jp;
pid_t pgrp;
int status;
jp = getjob(argv[1]);
if (jp->jobctl == 0)
error("job not created under job control");
printjobcmd(jp);
flushout(&output);
pgrp = jp->ps[0].pid;
tcsetpgrp(ttyfd, pgrp);
restartjob(jp);
jp->foreground = 1;
INTOFF;
status = waitforjob(jp, (int *)NULL);
INTON;
return status;
}
int
bgcmd(int argc, char **argv)
{
struct job *jp;
int i;
nextopt("");
do {
jp = getjob(*argptr, 0);
if (jp->jobctl == 0)
error("job not created under job control");
set_curjob(jp, 1);
out1fmt("[%ld] %s", (long)(jp - jobtab + 1), jp->ps[0].cmd);
for (i = 1; i < jp->nprocs; i++)
out1fmt(" | %s", jp->ps[i].cmd );
out1c('\n');
flushall();
restartjob(jp);
} while (*argptr && *++argptr);
return 0;
}
int
bgcmd(int argc, char **argv)
{
char s[64];
struct job *jp;
do {
jp = getjob(*++argv);
if (jp->jobctl == 0)
error("job not created under job control");
if (jp->state == JOBDONE)
continue;
restartjob(jp);
jp->foreground = 0;
fmtstr(s, 64, "[%td] ", jp - jobtab + 1);
out1str(s);
out1str(jp->ps[0].cmd);
out1c('\n');
} while (--argc > 1);
return 0;
}
int
jobscmd(int argc, char **argv)
{
int mode, m;
int sv = jobs_invalid;
jobs_invalid = 0;
mode = 0;
while ((m = nextopt("lp")))
if (m == 'l')
mode = SHOW_PID;
else
mode = SHOW_PGID;
if (*argptr)
do
showjob(out1, getjob(*argptr,0), mode);
while (*++argptr);
else
showjobs(out1, mode);
jobs_invalid = sv;
return 0;
}
int
jobscmd(int argc, char *argv[])
{
char *id;
int ch, mode;
optind = optreset = 1;
opterr = 0;
mode = SHOWJOBS_DEFAULT;
while ((ch = getopt(argc, argv, "lps")) != -1) {
switch (ch) {
case 'l':
mode = SHOWJOBS_VERBOSE;
break;
case 'p':
mode = SHOWJOBS_PGIDS;
break;
case 's':
mode = SHOWJOBS_PIDS;
break;
case '?':
default:
error("unknown option: -%c", optopt);
}
}
argc -= optind;
argv += optind;
if (argc == 0)
showjobs(0, mode);
else
while ((id = *argv++) != NULL)
showjob(getjob(id), 0, mode);
return (0);
}
}
jobctl = on;
}
#endif
#if JOBS
int
fgcmd(int argc __unused, char **argv __unused)
{
struct job *jp;
pid_t pgrp;
int status;
nextopt("");
jp = getjob(*argptr);
if (jp->jobctl == 0)
error("job not created under job control");
printjobcmd(jp);
flushout(&output);
pgrp = jp->ps[0].pid;
tcsetpgrp(ttyfd, pgrp);
restartjob(jp);
jp->foreground = 1;
INTOFF;
status = waitforjob(jp, (int *)NULL);
INTON;
return status;
}