From 52a97ca00cf5d290c9beb65ba7c217a5ed69ee42 Mon Sep 17 00:00:00 2001
From: Eric Andersen <andersen@codepoet.org>
Date: Fri, 22 Jun 2001 06:49:26 +0000
Subject: [PATCH] Some more cleanups. Of special importance, never free a pipe
that still has running jobs. Instead, we ignore it and expect it to be
cleaned by the background job stuff. -Erik
---
hush.c | 79 ++++++++++++++++++++++++++++++++++------------------
shell/hush.c | 79 ++++++++++++++++++++++++++++++++++------------------
2 files changed, 104 insertions(+), 54 deletions(-)
diff --git a/hush.c b/hush.c
index a9d3a16ac..fa01d9135 100644
--- a/hush.c
+++ b/hush.c
@@ -257,6 +257,7 @@ static char *PS2;
struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
struct variables *top_vars = &shell_ver;
+
#define B_CHUNK (100)
#define B_NOSPAC 1
@@ -394,7 +395,7 @@ static void remove_bg_job(struct pipe *pi);
static char *get_local_var(const char *var);
static void unset_local_var(const char *name);
static int set_local_var(const char *s, int flg_export);
-
+static void sigchld_handler(int sig);
/* Table of built-in functions. They can be forked or not, depending on
* context: within pipes, they fork. As simple commands, they do not.
@@ -556,7 +557,6 @@ static int builtin_fg_bg(struct child_prog *child)
error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
return EXIT_FAILURE;
}
-
for (pi = job_list; pi; pi = pi->next) {
if (pi->jobid == jobnum) {
break;
@@ -567,6 +567,7 @@ static int builtin_fg_bg(struct child_prog *child)
return EXIT_FAILURE;
}
}
+
if (*child->argv[0] == 'f') {
/* Make this job the foreground job */
signal(SIGTTOU, SIG_IGN);
@@ -613,6 +614,7 @@ static int builtin_jobs(struct child_prog *child)
status_string = "Stopped";
else
status_string = "Running";
+
printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
}
return EXIT_SUCCESS;
@@ -1142,7 +1144,7 @@ static void insert_bg_job(struct pipe *pi)
/* add thejob to the list of running jobs */
if (!job_list) {
- thejob = job_list= xmalloc(sizeof(*thejob));
+ thejob = job_list = xmalloc(sizeof(*thejob));
} else {
for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
thejob->next = xmalloc(sizeof(*thejob));
@@ -1178,14 +1180,14 @@ static void remove_bg_job(struct pipe *pi)
struct pipe *prev_pipe;
if (pi == job_list) {
- job_list= pi->next;
+ job_list = pi->next;
} else {
prev_pipe = job_list;
while (prev_pipe->next != pi)
prev_pipe = prev_pipe->next;
prev_pipe->next = pi->next;
}
-
+ pi->stopped_progs = 0;
free_pipe(pi, 0);
free(pi);
}
@@ -1210,7 +1212,7 @@ static int checkjobs(struct pipe* fg_pipe)
int i, rcode = 0;
for (i=0; i < fg_pipe->num_progs; i++) {
if (fg_pipe->progs[i].pid == childpid) {
- if (i==fg_pipe->num_progs-1)
+ if (i==fg_pipe->num_progs-1)
rcode=WEXITSTATUS(status);
(fg_pipe->num_progs)--;
return(rcode);
@@ -1220,8 +1222,9 @@ static int checkjobs(struct pipe* fg_pipe)
for (pi = job_list; pi; pi = pi->next) {
prognum = 0;
- while (prognum < pi->num_progs &&
- pi->progs[prognum].pid != childpid) prognum++;
+ while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
+ prognum++;
+ }
if (prognum < pi->num_progs)
break;
}
@@ -1245,9 +1248,14 @@ static int checkjobs(struct pipe* fg_pipe)
pi->stopped_progs++;
pi->progs[prognum].is_stopped = 1;
+#if 0
+ /* Printing this stuff is a pain, since it tends to
+ * overwrite the prompt an inconveinient moments. So
+ * don't do that. */
if (pi->stopped_progs == pi->num_progs) {
- printf(JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
+ printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
}
+#endif
}
}
@@ -1394,7 +1402,6 @@ static int run_pipe_real(struct pipe *pi)
/* XXX test for failed fork()? */
if (!(child->pid = fork())) {
-
signal(SIGTTOU, SIG_DFL);
close_all();
@@ -1414,7 +1421,7 @@ 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 (interactive && pi->followup!=PIPE_BG) {
/* If we (the child) win the race, put ourselves in the process
* group whose leader is the first process in this pipe. */
@@ -1423,15 +1430,17 @@ static int run_pipe_real(struct pipe *pi)
}
if (setpgid(0, pi->pgrp) == 0) {
signal(SIGTTOU, SIG_IGN);
- tcsetpgrp(ctty, pi->pgrp);
+ tcsetpgrp(2, pi->pgrp);
signal(SIGTTOU, SIG_DFL);
}
}
pseudo_exec(child);
}
- /* Put our child in the process group whose leader is the
- * first process in this pipe. */
+
+
+ /* put our child in the process group whose leader is the
+ first process in this pipe */
if (pi->pgrp < 0) {
pi->pgrp = child->pid;
}
@@ -1478,18 +1487,18 @@ static int run_list_real(struct pipe *pi)
insert_bg_job(pi);
rcode = EXIT_SUCCESS;
} else {
-
if (interactive) {
/* move the new process group into the foreground */
if (tcsetpgrp(ctty, pi->pgrp) && errno != ENOTTY)
perror_msg("tcsetpgrp-3");
rcode = checkjobs(pi);
+ /* move the shell to the foreground */
if (tcsetpgrp(ctty, getpgid(0)) && errno != ENOTTY)
perror_msg("tcsetpgrp-4");
} else {
rcode = checkjobs(pi);
}
- debug_printf("pipe_wait returned %d\n",rcode);
+ debug_printf("checkjobs returned %d\n",rcode);
}
last_return_code=rcode;
if ( rmode == RES_IF || rmode == RES_ELIF )
@@ -1517,6 +1526,9 @@ static int free_pipe(struct pipe *pi, int indent)
struct redir_struct *r, *rnext;
int a, i, ret_code=0;
char *ind = indenter(indent);
+
+ if (pi->stopped_progs > 0)
+ return ret_code;
final_printf("%s run pipe: (pid %d)\n",ind,getpid());
for (i=0; i<pi->num_progs; i++) {
child = &pi->progs[i];
@@ -2516,6 +2528,27 @@ static int parse_file_outer(FILE *f)
return rcode;
}
+static void sigchld_handler(int sig)
+{
+ checkjobs(NULL);
+ signal(SIGCHLD, sigchld_handler);
+}
+
+static void setup_job_control()
+{
+ /* If we get started under a job aware app (like bash
+ * for example), make sure we are now in charge so we
+ * don't fight over who gets the foreground */
+ /* don't pay any attention to this signal; it just confuses
+ things and isn't really meant for shells anyway */
+ setpgrp();
+ controlling_tty(0);
+ signal(SIGTTOU, SIG_IGN);
+ setpgid(0, getpid());
+ tcsetpgrp(ctty, getpid());
+ signal(SIGCHLD, sigchld_handler);
+}
+
int shell_main(int argc, char **argv)
{
@@ -2536,11 +2569,11 @@ int shell_main(int argc, char **argv)
interactive = 0;
close_me_head = NULL;
last_bg_pid = 0;
+ job_list = NULL;
last_jobid = 0;
/* Initialize some more globals to non-zero values */
set_cwd();
- job_list = NULL;
#ifdef BB_FEATURE_COMMAND_EDITING
cmdedit_set_initial_prompt();
#else
@@ -2558,16 +2591,6 @@ int shell_main(int argc, char **argv)
last_return_code=EXIT_SUCCESS;
- /* If we get started under a job aware app (like bash
- * for example), make sure we are now in charge so we
- * don't fight over who gets the foreground */
- /* don't pay any attention to this signal; it just confuses
- things and isn't really meant for shells anyway */
- controlling_tty(0);
- signal(SIGTTOU, SIG_IGN);
- setpgid(0, getpid());
- tcsetpgrp(ctty, getpid());
-
if (argv[0] && argv[0][0] == '-') {
debug_printf("\nsourcing /etc/profile\n");
input = xfopen("/etc/profile", "r");
@@ -2620,7 +2643,9 @@ int shell_main(int argc, char **argv)
if (interactive) {
/* Looks like they want an interactive shell */
fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n");
+ setup_job_control();
}
+
if (argv[optind]==NULL) {
opt=parse_file_outer(stdin);
goto final_return;
diff --git a/shell/hush.c b/shell/hush.c
index a9d3a16ac..fa01d9135 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -257,6 +257,7 @@ static char *PS2;
struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
struct variables *top_vars = &shell_ver;
+
#define B_CHUNK (100)
#define B_NOSPAC 1
@@ -394,7 +395,7 @@ static void remove_bg_job(struct pipe *pi);
static char *get_local_var(const char *var);
static void unset_local_var(const char *name);
static int set_local_var(const char *s, int flg_export);
-
+static void sigchld_handler(int sig);
/* Table of built-in functions. They can be forked or not, depending on
* context: within pipes, they fork. As simple commands, they do not.
@@ -556,7 +557,6 @@ static int builtin_fg_bg(struct child_prog *child)
error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
return EXIT_FAILURE;
}
-
for (pi = job_list; pi; pi = pi->next) {
if (pi->jobid == jobnum) {
break;
@@ -567,6 +567,7 @@ static int builtin_fg_bg(struct child_prog *child)
return EXIT_FAILURE;
}
}
+
if (*child->argv[0] == 'f') {
/* Make this job the foreground job */
signal(SIGTTOU, SIG_IGN);
@@ -613,6 +614,7 @@ static int builtin_jobs(struct child_prog *child)
status_string = "Stopped";
else
status_string = "Running";
+
printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
}
return EXIT_SUCCESS;
@@ -1142,7 +1144,7 @@ static void insert_bg_job(struct pipe *pi)
/* add thejob to the list of running jobs */
if (!job_list) {
- thejob = job_list= xmalloc(sizeof(*thejob));
+ thejob = job_list = xmalloc(sizeof(*thejob));
} else {
for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
thejob->next = xmalloc(sizeof(*thejob));
@@ -1178,14 +1180,14 @@ static void remove_bg_job(struct pipe *pi)
struct pipe *prev_pipe;
if (pi == job_list) {
- job_list= pi->next;
+ job_list = pi->next;
} else {
prev_pipe = job_list;
while (prev_pipe->next != pi)
prev_pipe = prev_pipe->next;
prev_pipe->next = pi->next;
}
-
+ pi->stopped_progs = 0;
free_pipe(pi, 0);
free(pi);
}
@@ -1210,7 +1212,7 @@ static int checkjobs(struct pipe* fg_pipe)
int i, rcode = 0;
for (i=0; i < fg_pipe->num_progs; i++) {
if (fg_pipe->progs[i].pid == childpid) {
- if (i==fg_pipe->num_progs-1)
+ if (i==fg_pipe->num_progs-1)
rcode=WEXITSTATUS(status);
(fg_pipe->num_progs)--;
return(rcode);
@@ -1220,8 +1222,9 @@ static int checkjobs(struct pipe* fg_pipe)
for (pi = job_list; pi; pi = pi->next) {
prognum = 0;
- while (prognum < pi->num_progs &&
- pi->progs[prognum].pid != childpid) prognum++;
+ while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
+ prognum++;
+ }
if (prognum < pi->num_progs)
break;
}
@@ -1245,9 +1248,14 @@ static int checkjobs(struct pipe* fg_pipe)
pi->stopped_progs++;
pi->progs[prognum].is_stopped = 1;
+#if 0
+ /* Printing this stuff is a pain, since it tends to
+ * overwrite the prompt an inconveinient moments. So
+ * don't do that. */
if (pi->stopped_progs == pi->num_progs) {
- printf(JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
+ printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
}
+#endif
}
}
@@ -1394,7 +1402,6 @@ static int run_pipe_real(struct pipe *pi)
/* XXX test for failed fork()? */
if (!(child->pid = fork())) {
-
signal(SIGTTOU, SIG_DFL);
close_all();
@@ -1414,7 +1421,7 @@ 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 (interactive && pi->followup!=PIPE_BG) {
/* If we (the child) win the race, put ourselves in the process
* group whose leader is the first process in this pipe. */
@@ -1423,15 +1430,17 @@ static int run_pipe_real(struct pipe *pi)
}
if (setpgid(0, pi->pgrp) == 0) {
signal(SIGTTOU, SIG_IGN);
- tcsetpgrp(ctty, pi->pgrp);
+ tcsetpgrp(2, pi->pgrp);
signal(SIGTTOU, SIG_DFL);
}
}
pseudo_exec(child);
}
- /* Put our child in the process group whose leader is the
- * first process in this pipe. */
+
+
+ /* put our child in the process group whose leader is the
+ first process in this pipe */
if (pi->pgrp < 0) {
pi->pgrp = child->pid;
}
@@ -1478,18 +1487,18 @@ static int run_list_real(struct pipe *pi)
insert_bg_job(pi);
rcode = EXIT_SUCCESS;
} else {
-
if (interactive) {
/* move the new process group into the foreground */
if (tcsetpgrp(ctty, pi->pgrp) && errno != ENOTTY)
perror_msg("tcsetpgrp-3");
rcode = checkjobs(pi);
+ /* move the shell to the foreground */
if (tcsetpgrp(ctty, getpgid(0)) && errno != ENOTTY)
perror_msg("tcsetpgrp-4");
} else {
rcode = checkjobs(pi);
}
- debug_printf("pipe_wait returned %d\n",rcode);
+ debug_printf("checkjobs returned %d\n",rcode);
}
last_return_code=rcode;
if ( rmode == RES_IF || rmode == RES_ELIF )
@@ -1517,6 +1526,9 @@ static int free_pipe(struct pipe *pi, int indent)
struct redir_struct *r, *rnext;
int a, i, ret_code=0;
char *ind = indenter(indent);
+
+ if (pi->stopped_progs > 0)
+ return ret_code;
final_printf("%s run pipe: (pid %d)\n",ind,getpid());
for (i=0; i<pi->num_progs; i++) {
child = &pi->progs[i];
@@ -2516,6 +2528,27 @@ static int parse_file_outer(FILE *f)
return rcode;
}
+static void sigchld_handler(int sig)
+{
+ checkjobs(NULL);
+ signal(SIGCHLD, sigchld_handler);
+}
+
+static void setup_job_control()
+{
+ /* If we get started under a job aware app (like bash
+ * for example), make sure we are now in charge so we
+ * don't fight over who gets the foreground */
+ /* don't pay any attention to this signal; it just confuses
+ things and isn't really meant for shells anyway */
+ setpgrp();
+ controlling_tty(0);
+ signal(SIGTTOU, SIG_IGN);
+ setpgid(0, getpid());
+ tcsetpgrp(ctty, getpid());
+ signal(SIGCHLD, sigchld_handler);
+}
+
int shell_main(int argc, char **argv)
{
@@ -2536,11 +2569,11 @@ int shell_main(int argc, char **argv)
interactive = 0;
close_me_head = NULL;
last_bg_pid = 0;
+ job_list = NULL;
last_jobid = 0;
/* Initialize some more globals to non-zero values */
set_cwd();
- job_list = NULL;
#ifdef BB_FEATURE_COMMAND_EDITING
cmdedit_set_initial_prompt();
#else
@@ -2558,16 +2591,6 @@ int shell_main(int argc, char **argv)
last_return_code=EXIT_SUCCESS;
- /* If we get started under a job aware app (like bash
- * for example), make sure we are now in charge so we
- * don't fight over who gets the foreground */
- /* don't pay any attention to this signal; it just confuses
- things and isn't really meant for shells anyway */
- controlling_tty(0);
- signal(SIGTTOU, SIG_IGN);
- setpgid(0, getpid());
- tcsetpgrp(ctty, getpid());
-
if (argv[0] && argv[0][0] == '-') {
debug_printf("\nsourcing /etc/profile\n");
input = xfopen("/etc/profile", "r");
@@ -2620,7 +2643,9 @@ int shell_main(int argc, char **argv)
if (interactive) {
/* Looks like they want an interactive shell */
fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n");
+ setup_job_control();
}
+
if (argv[optind]==NULL) {
opt=parse_file_outer(stdin);
goto final_return;