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authorEric Andersen <andersen@codepoet.org>2001-05-02 20:12:03 +0000
committerEric Andersen <andersen@codepoet.org>2001-05-02 20:12:03 +0000
commit0fcd447d59fffa2fafe090f0cd76bd115de02add (patch)
tree823273f25fefa1275601b36d290fe749d1914020 /shell
parent20a3069ec0d1c242404e089cecfcc5bb7a88df0f (diff)
downloadbusybox-0fcd447d59fffa2fafe090f0cd76bd115de02add.tar.gz
Some more job control updates. It will now sucessfully background
stuff. Good luck getting things back into the foreground though... -Erik
Diffstat (limited to 'shell')
-rw-r--r--shell/hush.c120
1 files changed, 74 insertions, 46 deletions
diff --git a/shell/hush.c b/shell/hush.c
index 01fd33486..4a16a3fa6 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -470,48 +470,53 @@ static int builtin_export(struct child_prog *child)
/* built-in 'fg' and 'bg' handler */
static int builtin_fg_bg(struct child_prog *child)
{
- int i, jobNum;
- struct pipe *job=NULL;
-
- if (!child->argv[1] || child->argv[2]) {
- error_msg("%s: exactly one argument is expected\n",
- child->argv[0]);
- return EXIT_FAILURE;
- }
-
- if (sscanf(child->argv[1], "%%%d", &jobNum) != 1) {
- error_msg("%s: bad argument '%s'\n",
- child->argv[0], child->argv[1]);
- return EXIT_FAILURE;
- }
+ int i, jobnum;
+ struct pipe *pi=NULL;
- for (job = job_list->head; job; job = job->next) {
- if (job->jobid == jobNum) {
- break;
+ /* If they gave us no args, assume they want the last backgrounded task */
+ if (!child->argv[1]) {
+ for (pi = job_list->head; pi; pi = pi->next) {
+ if (pi->progs && pi->progs->pid == last_bg_pid) {
+ break;
+ }
+ }
+ if (!pi) {
+ error_msg("%s: no current job", child->argv[0]);
+ return EXIT_FAILURE;
+ }
+ } else {
+ if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
+ error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
+ return EXIT_FAILURE;
}
- }
- if (!job) {
- error_msg("%s: unknown job %d\n",
- child->argv[0], jobNum);
- return EXIT_FAILURE;
+ for (pi = job_list->head; pi; pi = pi->next) {
+ if (pi->jobid == jobnum) {
+ break;
+ }
+ }
+ if (!pi) {
+ error_msg("%s: %d: no such job", child->argv[0], jobnum);
+ return EXIT_FAILURE;
+ }
}
-
if (*child->argv[0] == 'f') {
/* Make this job the foreground job */
+ signal(SIGTTOU, SIG_IGN);
/* suppress messages when run from /linuxrc mag@sysgo.de */
- if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
+ if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
perror_msg("tcsetpgrp");
- job_list->fg = job;
+ signal(SIGTTOU, SIG_DFL);
+ job_list->fg = pi;
}
/* Restart the processes in the job */
- for (i = 0; i < job->num_progs; i++)
- job->progs[i].is_stopped = 0;
+ for (i = 0; i < pi->num_progs; i++)
+ pi->progs[i].is_stopped = 0;
- kill(-job->pgrp, SIGCONT);
+ kill(-pi->pgrp, SIGCONT);
- job->stopped_progs = 0;
+ pi->stopped_progs = 0;
return EXIT_SUCCESS;
}
@@ -1055,7 +1060,7 @@ static void insert_bg_job(struct pipe *pi)
}
/* physically copy the struct job */
- *thejob = *pi;
+ memcpy(thejob, pi, sizeof(struct pipe));
thejob->next = NULL;
thejob->running_progs = thejob->num_progs;
thejob->stopped_progs = 0;
@@ -1103,6 +1108,7 @@ static void free_pipe(struct pipe *pi)
memset(pi, 0, sizeof(struct pipe));
}
+
/* Checks to see if any background processes have exited -- if they
have, figure out why and see if a job has completed */
static void checkjobs()
@@ -1169,14 +1175,27 @@ static void checkjobs()
static int run_pipe_real(struct pipe *pi)
{
int i;
+ int ctty;
int nextin, nextout;
int pipefds[2]; /* pipefds[0] is for reading */
struct child_prog *child;
struct built_in_command *x;
+ ctty = -1;
nextin = 0;
pi->pgrp = 0;
+ /* Check if we are supposed to run in the foreground */
+ if (pi->followup!=PIPE_BG) {
+ if ((pi->pgrp = tcgetpgrp(ctty = 2)) < 0
+ && (pi->pgrp = tcgetpgrp(ctty = 0)) < 0
+ && (pi->pgrp = tcgetpgrp(ctty = 1)) < 0)
+ return errno = ENOTTY, -1;
+
+ if (pi->pgrp < 0 && pi->pgrp != getpgrp())
+ return errno = EPERM, -1;
+ }
+
/* Check if this is a simple builtin (not part of a pipe).
* Builtins within pipes have to fork anyway, and are handled in
* pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
@@ -1225,6 +1244,7 @@ static int run_pipe_real(struct pipe *pi)
/* XXX test for failed fork()? */
if (!(child->pid = fork())) {
+
signal(SIGTTOU, SIG_DFL);
close_all();
@@ -1244,22 +1264,33 @@ static int run_pipe_real(struct pipe *pi)
/* Like bash, explicit redirects override pipes,
* and the pipe fd is available for dup'ing. */
setup_redirects(child,NULL);
+
+ if (pi->followup!=PIPE_BG) {
+ /* Put our child in the process group whose leader is the
+ * first process in this pipe. */
+ if (pi->pgrp < 0) {
+ pi->pgrp = child->pid;
+ }
+ /* Don't check for errors. The child may be dead already,
+ * in which case setpgid returns error code EACCES. */
+ if (setpgid(0, pi->pgrp) == 0) {
+ signal(SIGTTOU, SIG_IGN);
+ tcsetpgrp(ctty, pi->pgrp);
+ signal(SIGTTOU, SIG_DFL);
+ }
+ }
pseudo_exec(child);
}
- if (interactive) {
- /* Put our child in the process group whose leader is the
- * first process in this pipe. */
- if (pi->pgrp==0) {
- pi->pgrp = child->pid;
- }
- /* Don't check for errors. The child may be dead already,
- * in which case setpgid returns error code EACCES. */
- setpgid(child->pid, pi->pgrp);
+ /* Put our child in the process group whose leader is the
+ * first process in this pipe. */
+ if (pi->pgrp < 0) {
+ pi->pgrp = child->pid;
}
- /* In the non-interactive case, do nothing. Leave the children
- * with the process group that they inherited from us. */
-
+ /* Don't check for errors. The child may be dead already,
+ * in which case setpgid returns error code EACCES. */
+ setpgid(child->pid, pi->pgrp);
+
if (nextin != 0)
close(nextin);
if (nextout != 1)
@@ -1295,13 +1326,10 @@ static int run_list_real(struct pipe *pi)
/* XXX check bash's behavior with nontrivial pipes */
/* XXX compute jobid */
/* XXX what does bash do with attempts to background builtins? */
-#if 0
- printf("[%d] %d\n", pi->jobid, pi->pgrp);
- last_bg_pid = pi->pgrp;
-#endif
insert_bg_job(pi);
rcode = EXIT_SUCCESS;
} else {
+
if (interactive) {
/* move the new process group into the foreground */
/* suppress messages when run from /linuxrc mag@sysgo.de */