First pass at getting job control working. This gets the infrastructure

in place, but something is still missing/wrong in there.  Testing with
'grep foo &' seems to put _hush_ into the background.  Pondering...
 -Erik

2 files changed, 284 insertions, 26 deletions

diff --git a/hush.c b/hush.c
index 4641e59c8..ed4979818 100644
--- a/hush.c
+++ b/hush.c
@@ -213,7 +213,6 @@ struct pipe {
         int job_context;                        /* bitmask defining current context */
         pipe_style followup;            /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
         reserved_style r_mode;          /* supports if, for, while, until */
-        struct jobset *job_list;
 };
 
 struct jobset {
@@ -244,7 +243,7 @@ static int fake_mode=0;
 static int interactive=0;
 static struct close_me *close_me_head = NULL;
 static char *cwd;
-/* static struct jobset job_list = { NULL, NULL }; */
+static struct jobset *job_list;
 static unsigned int last_bg_pid=0;
 static char *PS1;
 static char *PS2 = "> ";
@@ -377,6 +376,11 @@ static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *in
 static int parse_stream_outer(struct in_str *inp);
 static int parse_string_outer(const char *s);
 static int parse_file_outer(FILE *f);
+/*   job management: */
+static void checkjobs();
+static void insert_bg_job(struct pipe *pi);
+static void remove_bg_job(struct pipe *pi);
+static void free_pipe(struct pipe *pi);
 
 /* Table of built-in functions.  They can be forked or not, depending on
  * context: within pipes, they fork.  As simple commands, they do not.
@@ -481,7 +485,7 @@ static int builtin_fg_bg(struct child_prog *child)
                 return EXIT_FAILURE;
         }
 
-        for (job = child->family->job_list->head; job; job = job->next) {
+        for (job = job_list->head; job; job = job->next) {
                 if (job->jobid == jobNum) {
                         break;
                 }
@@ -498,7 +502,7 @@ static int builtin_fg_bg(struct child_prog *child)
                 /* suppress messages when run from /linuxrc mag@sysgo.de */
                 if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
                         perror_msg("tcsetpgrp"); 
-                child->family->job_list->fg = job;
+                job_list->fg = job;
         }
 
         /* Restart the processes in the job */
@@ -533,7 +537,7 @@ static int builtin_jobs(struct child_prog *child)
         struct pipe *job;
         char *status_string;
 
-        for (job = child->family->job_list->head; job; job = job->next) {
+        for (job = job_list->head; job; job = job->next) {
                 if (job->running_progs == job->stopped_progs)
                         status_string = "Stopped";
                 else
@@ -1031,6 +1035,121 @@ static void pseudo_exec(struct child_prog *child)
         }
 }
 
+static void insert_bg_job(struct pipe *pi)
+{
+        struct pipe *thejob;
+
+        /* Linear search for the ID of the job to use */
+        pi->jobid = 1;
+        for (thejob = job_list->head; thejob; thejob = thejob->next)
+                if (thejob->jobid >= pi->jobid)
+                        pi->jobid = thejob->jobid + 1;
+
+        /* add thejob to the list of running jobs */
+        if (!job_list->head) {
+                thejob = job_list->head = xmalloc(sizeof(*thejob));
+        } else {
+                for (thejob = job_list->head; thejob->next; thejob = thejob->next) /* nothing */;
+                thejob->next = xmalloc(sizeof(*thejob));
+                thejob = thejob->next;
+        }
+
+        /* physically copy the struct job */
+        *thejob = *pi;   
+        thejob->next = NULL;
+        thejob->running_progs = thejob->num_progs;
+        thejob->stopped_progs = 0;
+
+        /* we don't wait for background thejobs to return -- append it 
+           to the list of backgrounded thejobs and leave it alone */
+        printf("[%d] %d\n", pi->jobid, pi->pgrp);
+        last_bg_pid = pi->pgrp;
+}
+
+/* remove a backgrounded job from a jobset */
+static void remove_bg_job(struct pipe *pi)
+{
+        struct pipe *prev_pipe;
+
+        free_pipe(pi);
+        if (pi == job_list->head) {
+                job_list->head = pi->next;
+        } else {
+                prev_pipe = job_list->head;
+                while (prev_pipe->next != pi)
+                        prev_pipe = prev_pipe->next;
+                prev_pipe->next = pi->next;
+        }
+
+        free(pi);
+}
+
+/* free up all memory from a pipe */
+static void free_pipe(struct pipe *pi)
+{
+        int i;
+
+        for (i = 0; i < pi->num_progs; i++) {
+                free(pi->progs[i].argv);
+                if (pi->progs[i].redirects)
+                        free(pi->progs[i].redirects);
+        }
+        if (pi->progs)
+                free(pi->progs);
+        if (pi->text)
+                free(pi->text);
+        if (pi->cmdbuf)
+                free(pi->cmdbuf);
+        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()
+{
+        int status;
+        int prognum = 0;
+        struct pipe *pi;
+        pid_t childpid;
+
+        while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
+                for (pi = job_list->head; pi; pi = pi->next) {
+                        prognum = 0;
+                        while (prognum < pi->num_progs &&
+                                   pi->progs[prognum].pid != childpid) prognum++;
+                        if (prognum < pi->num_progs)
+                                break;
+                }
+
+                if (WIFEXITED(status) || WIFSIGNALED(status)) {
+                        /* child exited */
+                        pi->running_progs--;
+                        pi->progs[prognum].pid = 0;
+
+                        if (!pi->running_progs) {
+                                printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
+                                remove_bg_job(pi);
+                        }
+                } else {
+                        /* child stopped */
+                        pi->stopped_progs++;
+                        pi->progs[prognum].is_stopped = 1;
+
+                        if (pi->stopped_progs == pi->num_progs) {
+                                printf(JOB_STATUS_FORMAT, pi->jobid, "Stopped",
+                                                pi->text);
+                        }
+                }
+        }
+
+        /* move the shell to the foreground */
+        if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
+                perror_msg("tcsetpgrp"); 
+
+        if (childpid == -1 && errno != ECHILD)
+                perror_msg("waitpid");
+}
+
 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
  * to finish.  See pipe_wait().
  *
@@ -1106,6 +1225,8 @@ static int run_pipe_real(struct pipe *pi)
 
                 /* XXX test for failed fork()? */
                 if (!(child->pid = fork())) {
+                        signal(SIGTTOU, SIG_DFL);
+                        
                         close_all();
 
                         if (nextin != 0) {
@@ -1174,22 +1295,25 @@ 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 */
-                                signal(SIGTTIN, SIG_IGN);
-                                signal(SIGTTOU, SIG_IGN);
+                                //signal(SIGTTIN, SIG_IGN);
+                                //signal(SIGTTOU, SIG_IGN);
                                 if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
                                         perror_msg("tcsetpgrp");
                                 rcode = pipe_wait(pi);
                                 if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
                                         perror_msg("tcsetpgrp");
-                                signal(SIGTTIN, SIG_DFL);
-                                signal(SIGTTOU, SIG_DFL);
+                                //signal(SIGTTIN, SIG_DFL);
+                                //signal(SIGTTOU, SIG_DFL);
                         } else {
                                 rcode = pipe_wait(pi);
                         }
@@ -1202,6 +1326,7 @@ static int run_list_real(struct pipe *pi)
                         skip_more_in_this_rmode=rmode;
                         /* return rcode; */ /* XXX broken if list is part of if/then/else */
         }
+        checkjobs();
         return rcode;
 }
 
@@ -1298,7 +1423,7 @@ static int globhack(const char *src, int flags, glob_t *pglob)
         int cnt, pathc;
         const char *s;
         char *dest;
-        for (cnt=1, s=src; s && *s; s++) {
+        for (cnt=1, s=src; *s; s++) {
                 if (*s == '\\') s++;
                 cnt++;
         }
@@ -1315,7 +1440,7 @@ static int globhack(const char *src, int flags, glob_t *pglob)
         if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
         pglob->gl_pathv[pathc-1]=dest;
         pglob->gl_pathv[pathc]=NULL;
-        for (s=src; s && *s; s++, dest++) {
+        for (s=src; *s; s++, dest++) {
                 if (*s == '\\') s++;
                 *dest = *s;
         }
@@ -1482,8 +1607,6 @@ int reserved_word(o_string *dest, struct p_context *ctx)
                 { "done",  RES_DONE,  FLAG_END  }
         };
         struct reserved_combo *r;
-        if (dest->data == NULL)
-                return 0;
         for (r=reserved_list;
 #define NRES sizeof(reserved_list)/sizeof(struct reserved_combo)
                 r<reserved_list+NRES; r++) {
@@ -2080,6 +2203,8 @@ int shell_main(int argc, char **argv)
 {
         int opt;
         FILE *input;
+        struct jobset joblist_end = { NULL, NULL };
+        job_list = &joblist_end;
 
         last_return_code=EXIT_SUCCESS;
 
@@ -2087,6 +2212,10 @@ int shell_main(int argc, char **argv)
         global_argc = argc;
         global_argv = argv;
 
+        /* don't pay any attention to this signal; it just confuses 
+           things and isn't really meant for shells anyway */
+        signal(SIGTTOU, SIG_IGN);
+
         if (argv[0] && argv[0][0] == '-') {
                 debug_printf("\nsourcing /etc/profile\n");
                 input = xfopen("/etc/profile", "r");
diff --git a/shell/hush.c b/shell/hush.c
index 4641e59c8..ed4979818 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -213,7 +213,6 @@ struct pipe {
         int job_context;                        /* bitmask defining current context */
         pipe_style followup;            /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
         reserved_style r_mode;          /* supports if, for, while, until */
-        struct jobset *job_list;
 };
 
 struct jobset {
@@ -244,7 +243,7 @@ static int fake_mode=0;
 static int interactive=0;
 static struct close_me *close_me_head = NULL;
 static char *cwd;
-/* static struct jobset job_list = { NULL, NULL }; */
+static struct jobset *job_list;
 static unsigned int last_bg_pid=0;
 static char *PS1;
 static char *PS2 = "> ";
@@ -377,6 +376,11 @@ static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *in
 static int parse_stream_outer(struct in_str *inp);
 static int parse_string_outer(const char *s);
 static int parse_file_outer(FILE *f);
+/*   job management: */
+static void checkjobs();
+static void insert_bg_job(struct pipe *pi);
+static void remove_bg_job(struct pipe *pi);
+static void free_pipe(struct pipe *pi);
 
 /* Table of built-in functions.  They can be forked or not, depending on
  * context: within pipes, they fork.  As simple commands, they do not.
@@ -481,7 +485,7 @@ static int builtin_fg_bg(struct child_prog *child)
                 return EXIT_FAILURE;
         }
 
-        for (job = child->family->job_list->head; job; job = job->next) {
+        for (job = job_list->head; job; job = job->next) {
                 if (job->jobid == jobNum) {
                         break;
                 }
@@ -498,7 +502,7 @@ static int builtin_fg_bg(struct child_prog *child)
                 /* suppress messages when run from /linuxrc mag@sysgo.de */
                 if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
                         perror_msg("tcsetpgrp"); 
-                child->family->job_list->fg = job;
+                job_list->fg = job;
         }
 
         /* Restart the processes in the job */
@@ -533,7 +537,7 @@ static int builtin_jobs(struct child_prog *child)
         struct pipe *job;
         char *status_string;
 
-        for (job = child->family->job_list->head; job; job = job->next) {
+        for (job = job_list->head; job; job = job->next) {
                 if (job->running_progs == job->stopped_progs)
                         status_string = "Stopped";
                 else
@@ -1031,6 +1035,121 @@ static void pseudo_exec(struct child_prog *child)
         }
 }
 
+static void insert_bg_job(struct pipe *pi)
+{
+        struct pipe *thejob;
+
+        /* Linear search for the ID of the job to use */
+        pi->jobid = 1;
+        for (thejob = job_list->head; thejob; thejob = thejob->next)
+                if (thejob->jobid >= pi->jobid)
+                        pi->jobid = thejob->jobid + 1;
+
+        /* add thejob to the list of running jobs */
+        if (!job_list->head) {
+                thejob = job_list->head = xmalloc(sizeof(*thejob));
+        } else {
+                for (thejob = job_list->head; thejob->next; thejob = thejob->next) /* nothing */;
+                thejob->next = xmalloc(sizeof(*thejob));
+                thejob = thejob->next;
+        }
+
+        /* physically copy the struct job */
+        *thejob = *pi;   
+        thejob->next = NULL;
+        thejob->running_progs = thejob->num_progs;
+        thejob->stopped_progs = 0;
+
+        /* we don't wait for background thejobs to return -- append it 
+           to the list of backgrounded thejobs and leave it alone */
+        printf("[%d] %d\n", pi->jobid, pi->pgrp);
+        last_bg_pid = pi->pgrp;
+}
+
+/* remove a backgrounded job from a jobset */
+static void remove_bg_job(struct pipe *pi)
+{
+        struct pipe *prev_pipe;
+
+        free_pipe(pi);
+        if (pi == job_list->head) {
+                job_list->head = pi->next;
+        } else {
+                prev_pipe = job_list->head;
+                while (prev_pipe->next != pi)
+                        prev_pipe = prev_pipe->next;
+                prev_pipe->next = pi->next;
+        }
+
+        free(pi);
+}
+
+/* free up all memory from a pipe */
+static void free_pipe(struct pipe *pi)
+{
+        int i;
+
+        for (i = 0; i < pi->num_progs; i++) {
+                free(pi->progs[i].argv);
+                if (pi->progs[i].redirects)
+                        free(pi->progs[i].redirects);
+        }
+        if (pi->progs)
+                free(pi->progs);
+        if (pi->text)
+                free(pi->text);
+        if (pi->cmdbuf)
+                free(pi->cmdbuf);
+        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()
+{
+        int status;
+        int prognum = 0;
+        struct pipe *pi;
+        pid_t childpid;
+
+        while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
+                for (pi = job_list->head; pi; pi = pi->next) {
+                        prognum = 0;
+                        while (prognum < pi->num_progs &&
+                                   pi->progs[prognum].pid != childpid) prognum++;
+                        if (prognum < pi->num_progs)
+                                break;
+                }
+
+                if (WIFEXITED(status) || WIFSIGNALED(status)) {
+                        /* child exited */
+                        pi->running_progs--;
+                        pi->progs[prognum].pid = 0;
+
+                        if (!pi->running_progs) {
+                                printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
+                                remove_bg_job(pi);
+                        }
+                } else {
+                        /* child stopped */
+                        pi->stopped_progs++;
+                        pi->progs[prognum].is_stopped = 1;
+
+                        if (pi->stopped_progs == pi->num_progs) {
+                                printf(JOB_STATUS_FORMAT, pi->jobid, "Stopped",
+                                                pi->text);
+                        }
+                }
+        }
+
+        /* move the shell to the foreground */
+        if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
+                perror_msg("tcsetpgrp"); 
+
+        if (childpid == -1 && errno != ECHILD)
+                perror_msg("waitpid");
+}
+
 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
  * to finish.  See pipe_wait().
  *
@@ -1106,6 +1225,8 @@ static int run_pipe_real(struct pipe *pi)
 
                 /* XXX test for failed fork()? */
                 if (!(child->pid = fork())) {
+                        signal(SIGTTOU, SIG_DFL);
+                        
                         close_all();
 
                         if (nextin != 0) {
@@ -1174,22 +1295,25 @@ 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 */
-                                signal(SIGTTIN, SIG_IGN);
-                                signal(SIGTTOU, SIG_IGN);
+                                //signal(SIGTTIN, SIG_IGN);
+                                //signal(SIGTTOU, SIG_IGN);
                                 if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
                                         perror_msg("tcsetpgrp");
                                 rcode = pipe_wait(pi);
                                 if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
                                         perror_msg("tcsetpgrp");
-                                signal(SIGTTIN, SIG_DFL);
-                                signal(SIGTTOU, SIG_DFL);
+                                //signal(SIGTTIN, SIG_DFL);
+                                //signal(SIGTTOU, SIG_DFL);
                         } else {
                                 rcode = pipe_wait(pi);
                         }
@@ -1202,6 +1326,7 @@ static int run_list_real(struct pipe *pi)
                         skip_more_in_this_rmode=rmode;
                         /* return rcode; */ /* XXX broken if list is part of if/then/else */
         }
+        checkjobs();
         return rcode;
 }
 
@@ -1298,7 +1423,7 @@ static int globhack(const char *src, int flags, glob_t *pglob)
         int cnt, pathc;
         const char *s;
         char *dest;
-        for (cnt=1, s=src; s && *s; s++) {
+        for (cnt=1, s=src; *s; s++) {
                 if (*s == '\\') s++;
                 cnt++;
         }
@@ -1315,7 +1440,7 @@ static int globhack(const char *src, int flags, glob_t *pglob)
         if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
         pglob->gl_pathv[pathc-1]=dest;
         pglob->gl_pathv[pathc]=NULL;
-        for (s=src; s && *s; s++, dest++) {
+        for (s=src; *s; s++, dest++) {
                 if (*s == '\\') s++;
                 *dest = *s;
         }
@@ -1482,8 +1607,6 @@ int reserved_word(o_string *dest, struct p_context *ctx)
                 { "done",  RES_DONE,  FLAG_END  }
         };
         struct reserved_combo *r;
-        if (dest->data == NULL)
-                return 0;
         for (r=reserved_list;
 #define NRES sizeof(reserved_list)/sizeof(struct reserved_combo)
                 r<reserved_list+NRES; r++) {
@@ -2080,6 +2203,8 @@ int shell_main(int argc, char **argv)
 {
         int opt;
         FILE *input;
+        struct jobset joblist_end = { NULL, NULL };
+        job_list = &joblist_end;
 
         last_return_code=EXIT_SUCCESS;
 
@@ -2087,6 +2212,10 @@ int shell_main(int argc, char **argv)
         global_argc = argc;
         global_argv = argv;
 
+        /* don't pay any attention to this signal; it just confuses 
+           things and isn't really meant for shells anyway */
+        signal(SIGTTOU, SIG_IGN);
+
         if (argv[0] && argv[0][0] == '-') {
                 debug_printf("\nsourcing /etc/profile\n");
                 input = xfopen("/etc/profile", "r");