From 0fcd447d59fffa2fafe090f0cd76bd115de02add Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Wed, 2 May 2001 20:12:03 +0000 Subject: [PATCH] Some more job control updates. It will now sucessfully background stuff. Good luck getting things back into the foreground though... -Erik --- hush.c | 120 +++++++++++++++++++++++++++++++-------------------- shell/hush.c | 120 +++++++++++++++++++++++++++++++-------------------- 2 files changed, 148 insertions(+), 92 deletions(-) diff --git a/hush.c b/hush.c index 01fd33486..4a16a3fa6 100644 --- a/hush.c +++ b/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 */ 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 */ -- 2.25.1