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

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;