/* jobs.c - functions that make children, remember them, and handle their termination. */ /* This file works with both POSIX and BSD systems. It implements job control. */ /* Copyright (C) 1989-2022 Free Software Foundation, Inc. This file is part of GNU Bash, the Bourne Again SHell. Bash is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. Bash is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Bash. If not, see . */ #include "config.h" #include "bashtypes.h" #include "trap.h" #include #include #include #if defined (HAVE_UNISTD_H) # include #endif #include "posixtime.h" #if defined (HAVE_SYS_RESOURCE_H) && defined (HAVE_WAIT3) && !defined (_POSIX_VERSION) && !defined (RLIMTYPE) # include #endif /* !_POSIX_VERSION && HAVE_SYS_RESOURCE_H && HAVE_WAIT3 && !RLIMTYPE */ #if defined (HAVE_SYS_FILE_H) # include #endif #include "filecntl.h" #include #if defined (HAVE_SYS_PARAM_H) #include #endif #if defined (BUFFERED_INPUT) # include "input.h" #endif /* Need to include this up here for *_TTY_DRIVER definitions. */ #include "shtty.h" /* Define this if your output is getting swallowed. It's a no-op on machines with the termio or termios tty drivers. */ /* #define DRAIN_OUTPUT */ /* For the TIOCGPGRP and TIOCSPGRP ioctl parameters on HP-UX */ #if defined (hpux) && !defined (TERMIOS_TTY_DRIVER) # include #endif /* hpux && !TERMIOS_TTY_DRIVER */ #include "bashansi.h" #include "bashintl.h" #include "shell.h" #include "parser.h" #include "jobs.h" #include "execute_cmd.h" #include "flags.h" #include "typemax.h" #include "builtins/builtext.h" #include "builtins/common.h" #if defined (READLINE) # include #endif #if !defined (errno) extern int errno; #endif /* !errno */ #if !defined (HAVE_KILLPG) extern int killpg PARAMS((pid_t, int)); #endif #if !DEFAULT_CHILD_MAX # define DEFAULT_CHILD_MAX 4096 #endif #if !MAX_CHILD_MAX # define MAX_CHILD_MAX 32768 #endif #if !defined (DEBUG) #define MAX_JOBS_IN_ARRAY 4096 /* production */ #else #define MAX_JOBS_IN_ARRAY 128 /* testing */ #endif /* XXX for now */ #define PIDSTAT_TABLE_SZ 4096 #define BGPIDS_TABLE_SZ 512 /* Flag values for second argument to delete_job */ #define DEL_WARNSTOPPED 1 /* warn about deleting stopped jobs */ #define DEL_NOBGPID 2 /* don't add pgrp leader to bgpids */ /* Take care of system dependencies that must be handled when waiting for children. The arguments to the WAITPID macro match those to the Posix.1 waitpid() function. */ #if defined (ultrix) && defined (mips) && defined (_POSIX_VERSION) # define WAITPID(pid, statusp, options) \ wait3 ((union wait *)statusp, options, (struct rusage *)0) #else # if defined (_POSIX_VERSION) || defined (HAVE_WAITPID) # define WAITPID(pid, statusp, options) \ waitpid ((pid_t)pid, statusp, options) # else # if defined (HAVE_WAIT3) # define WAITPID(pid, statusp, options) \ wait3 (statusp, options, (struct rusage *)0) # else # define WAITPID(pid, statusp, options) \ wait3 (statusp, options, (int *)0) # endif /* HAVE_WAIT3 */ # endif /* !_POSIX_VERSION && !HAVE_WAITPID*/ #endif /* !(Ultrix && mips && _POSIX_VERSION) */ /* getpgrp () varies between systems. Even systems that claim to be Posix.1 compatible lie sometimes (Ultrix, SunOS4, apollo). */ #if defined (GETPGRP_VOID) # define getpgid(p) getpgrp () #else # define getpgid(p) getpgrp (p) #endif /* !GETPGRP_VOID */ /* If the system needs it, REINSTALL_SIGCHLD_HANDLER will reinstall the handler for SIGCHLD. */ #if defined (MUST_REINSTALL_SIGHANDLERS) # define REINSTALL_SIGCHLD_HANDLER signal (SIGCHLD, sigchld_handler) #else # define REINSTALL_SIGCHLD_HANDLER #endif /* !MUST_REINSTALL_SIGHANDLERS */ /* Some systems let waitpid(2) tell callers about stopped children. */ #if !defined (WCONTINUED) || defined (WCONTINUED_BROKEN) # undef WCONTINUED # define WCONTINUED 0 #endif #if !defined (WIFCONTINUED) # define WIFCONTINUED(s) (0) #endif /* The number of additional slots to allocate when we run out. */ #define JOB_SLOTS 8 typedef int sh_job_map_func_t PARAMS((JOB *, int, int, int)); /* Variables used here but defined in other files. */ extern WORD_LIST *subst_assign_varlist; extern SigHandler **original_signals; extern void set_original_signal PARAMS((int, SigHandler *)); static struct jobstats zerojs = { -1L, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, NO_JOB, NO_JOB, 0, 0 }; struct jobstats js = { -1L, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, NO_JOB, NO_JOB, 0, 0 }; ps_index_t pidstat_table[PIDSTAT_TABLE_SZ]; struct bgpids bgpids = { 0, 0, 0, 0 }; struct procchain procsubs = { 0, 0, 0 }; /* The array of known jobs. */ JOB **jobs = (JOB **)NULL; #if 0 /* The number of slots currently allocated to JOBS. */ int job_slots = 0; #endif /* The controlling tty for this shell. */ int shell_tty = -1; /* The shell's process group. */ pid_t shell_pgrp = NO_PID; /* The terminal's process group. */ pid_t terminal_pgrp = NO_PID; /* The process group of the shell's parent. */ pid_t original_pgrp = NO_PID; /* The process group of the pipeline currently being made. */ pid_t pipeline_pgrp = (pid_t)0; #if defined (PGRP_PIPE) /* Pipes which each shell uses to communicate with the process group leader until all of the processes in a pipeline have been started. Then the process leader is allowed to continue. */ int pgrp_pipe[2] = { -1, -1 }; #endif /* Last child made by the shell. */ volatile pid_t last_made_pid = NO_PID; /* Pid of the last asynchronous child. */ volatile pid_t last_asynchronous_pid = NO_PID; /* The pipeline currently being built. */ PROCESS *the_pipeline = (PROCESS *)NULL; /* If this is non-zero, do job control. */ int job_control = 1; /* Are we running in background? (terminal_pgrp != shell_pgrp) */ int running_in_background = 0; /* Call this when you start making children. */ int already_making_children = 0; /* If this is non-zero, $LINES and $COLUMNS are reset after every process exits from get_tty_state(). */ int check_window_size = CHECKWINSIZE_DEFAULT; PROCESS *last_procsub_child = (PROCESS *)NULL; /* Functions local to this file. */ void debug_print_pgrps (void); static sighandler wait_sigint_handler PARAMS((int)); static sighandler sigchld_handler PARAMS((int)); static sighandler sigcont_sighandler PARAMS((int)); static sighandler sigstop_sighandler PARAMS((int)); static int waitchld PARAMS((pid_t, int)); static PROCESS *find_pid_in_pipeline PARAMS((pid_t, PROCESS *, int)); static PROCESS *find_pipeline PARAMS((pid_t, int, int *)); static PROCESS *find_process PARAMS((pid_t, int, int *)); static char *current_working_directory PARAMS((void)); static char *job_working_directory PARAMS((void)); static char *j_strsignal PARAMS((int)); static char *printable_job_status PARAMS((int, PROCESS *, int)); static PROCESS *find_last_proc PARAMS((int, int)); static pid_t find_last_pid PARAMS((int, int)); static int set_new_line_discipline PARAMS((int)); static int map_over_jobs PARAMS((sh_job_map_func_t *, int, int)); static int job_last_stopped PARAMS((int)); static int job_last_running PARAMS((int)); static int most_recent_job_in_state PARAMS((int, JOB_STATE)); static int find_job PARAMS((pid_t, int, PROCESS **)); static int print_job PARAMS((JOB *, int, int, int)); static int process_exit_status PARAMS((WAIT)); static int process_exit_signal PARAMS((WAIT)); static int set_job_status_and_cleanup PARAMS((int)); static WAIT job_signal_status PARAMS((int)); static WAIT raw_job_exit_status PARAMS((int)); static void notify_of_job_status PARAMS((void)); static void reset_job_indices PARAMS((void)); static void cleanup_dead_jobs PARAMS((void)); static int processes_in_job PARAMS((int)); static void realloc_jobs_list PARAMS((void)); static int compact_jobs_list PARAMS((int)); static void add_process PARAMS((char *, pid_t)); static void print_pipeline PARAMS((PROCESS *, int, int, FILE *)); static void pretty_print_job PARAMS((int, int, FILE *)); static void set_current_job PARAMS((int)); static void reset_current PARAMS((void)); static void set_job_running PARAMS((int)); static void setjstatus PARAMS((int)); static int maybe_give_terminal_to PARAMS((pid_t, pid_t, int)); static void mark_all_jobs_as_dead PARAMS((void)); static void mark_dead_jobs_as_notified PARAMS((int)); static void restore_sigint_handler PARAMS((void)); #if defined (PGRP_PIPE) static void pipe_read PARAMS((int *)); #endif /* Hash table manipulation */ static ps_index_t *pshash_getbucket PARAMS((pid_t)); static void pshash_delindex PARAMS((ps_index_t)); /* Saved background process status management */ static struct pidstat *bgp_add PARAMS((pid_t, int)); static int bgp_delete PARAMS((pid_t)); static void bgp_clear PARAMS((void)); static int bgp_search PARAMS((pid_t)); static struct pipeline_saver *alloc_pipeline_saver PARAMS((void)); static ps_index_t bgp_getindex PARAMS((void)); static void bgp_resize PARAMS((void)); /* XXX */ #if defined (ARRAY_VARS) static int *pstatuses; /* list of pipeline statuses */ static int statsize; #endif /* Used to synchronize between wait_for and other functions and the SIGCHLD signal handler. */ static int sigchld; static int queue_sigchld; #define QUEUE_SIGCHLD(os) (os) = sigchld, queue_sigchld++ /* We set queue_sigchld around the call to waitchld to protect data structures from a SIGCHLD arriving while waitchld is executing. */ #define UNQUEUE_SIGCHLD(os) \ do { \ queue_sigchld--; \ if (queue_sigchld == 0 && os != sigchld) \ { \ queue_sigchld = 1; \ waitchld (-1, 0); \ queue_sigchld = 0; \ } \ } while (0) static SigHandler *old_tstp, *old_ttou, *old_ttin; static SigHandler *old_cont = (SigHandler *)SIG_DFL; /* A place to temporarily save the current pipeline. */ static struct pipeline_saver *saved_pipeline; static int saved_already_making_children; /* Set this to non-zero whenever you don't want the jobs list to change at all: no jobs deleted and no status change notifications. This is used, for example, when executing SIGCHLD traps, which may run arbitrary commands. */ static int jobs_list_frozen; static char retcode_name_buffer[64]; #if !defined (_POSIX_VERSION) /* These are definitions to map POSIX 1003.1 functions onto existing BSD library functions and system calls. */ #define setpgid(pid, pgrp) setpgrp (pid, pgrp) #define tcsetpgrp(fd, pgrp) ioctl ((fd), TIOCSPGRP, &(pgrp)) pid_t tcgetpgrp (fd) int fd; { pid_t pgrp; /* ioctl will handle setting errno correctly. */ if (ioctl (fd, TIOCGPGRP, &pgrp) < 0) return (-1); return (pgrp); } #endif /* !_POSIX_VERSION */ /* Initialize the global job stats structure and other bookkeeping variables */ void init_job_stats () { js = zerojs; } /* Return the working directory for the current process. Unlike job_working_directory, this does not call malloc (), nor do any of the functions it calls. This is so that it can safely be called from a signal handler. */ static char * current_working_directory () { char *dir; static char d[PATH_MAX]; dir = get_string_value ("PWD"); if (dir == 0 && the_current_working_directory && no_symbolic_links) dir = the_current_working_directory; if (dir == 0) { dir = getcwd (d, sizeof(d)); if (dir) dir = d; } return (dir == 0) ? "" : dir; } /* Return the working directory for the current process. */ static char * job_working_directory () { char *dir; dir = get_string_value ("PWD"); if (dir) return (savestring (dir)); dir = get_working_directory ("job-working-directory"); if (dir) return (dir); return (savestring ("")); } void making_children () { if (already_making_children) return; already_making_children = 1; start_pipeline (); } void stop_making_children () { already_making_children = 0; } void cleanup_the_pipeline () { PROCESS *disposer; sigset_t set, oset; BLOCK_CHILD (set, oset); disposer = the_pipeline; the_pipeline = (PROCESS *)NULL; UNBLOCK_CHILD (oset); if (disposer) discard_pipeline (disposer); } /* Not used right now */ void discard_last_procsub_child () { PROCESS *disposer; sigset_t set, oset; BLOCK_CHILD (set, oset); disposer = last_procsub_child; last_procsub_child = (PROCESS *)NULL; UNBLOCK_CHILD (oset); if (disposer) discard_pipeline (disposer); } static struct pipeline_saver * alloc_pipeline_saver () { struct pipeline_saver *ret; ret = (struct pipeline_saver *)xmalloc (sizeof (struct pipeline_saver)); ret->pipeline = 0; ret->next = 0; return ret; } void save_pipeline (clear) int clear; { sigset_t set, oset; struct pipeline_saver *saver; BLOCK_CHILD (set, oset); saver = alloc_pipeline_saver (); saver->pipeline = the_pipeline; saver->next = saved_pipeline; saved_pipeline = saver; if (clear) the_pipeline = (PROCESS *)NULL; saved_already_making_children = already_making_children; UNBLOCK_CHILD (oset); } PROCESS * restore_pipeline (discard) int discard; { PROCESS *old_pipeline; sigset_t set, oset; struct pipeline_saver *saver; BLOCK_CHILD (set, oset); old_pipeline = the_pipeline; the_pipeline = saved_pipeline->pipeline; saver = saved_pipeline; saved_pipeline = saved_pipeline->next; free (saver); already_making_children = saved_already_making_children; UNBLOCK_CHILD (oset); if (discard && old_pipeline) { discard_pipeline (old_pipeline); return ((PROCESS *)NULL); } return old_pipeline; } /* Start building a pipeline. */ void start_pipeline () { if (the_pipeline) { cleanup_the_pipeline (); /* If job_control == 0, pipeline_pgrp will always be equal to shell_pgrp; if job_control != 0, pipeline_pgrp == shell_pgrp for command and process substitution, in which case we want it to be the same as shell_pgrp for the lifetime of this shell instance. */ if (pipeline_pgrp != shell_pgrp) pipeline_pgrp = 0; #if defined (PGRP_PIPE) sh_closepipe (pgrp_pipe); #endif } #if defined (PGRP_PIPE) if (job_control) { if (pipe (pgrp_pipe) == -1) sys_error (_("start_pipeline: pgrp pipe")); } #endif } /* Stop building a pipeline. Install the process list in the job array. This returns the index of the newly installed job. DEFERRED is a command structure to be executed upon satisfactory execution exit of this pipeline. */ int stop_pipeline (async, deferred) int async; COMMAND *deferred; { register int i, j; JOB *newjob; sigset_t set, oset; BLOCK_CHILD (set, oset); #if defined (PGRP_PIPE) /* The parent closes the process group synchronization pipe. */ sh_closepipe (pgrp_pipe); #endif cleanup_dead_jobs (); if (js.j_jobslots == 0) { js.j_jobslots = JOB_SLOTS; jobs = (JOB **)xmalloc (js.j_jobslots * sizeof (JOB *)); /* Now blank out these new entries. */ for (i = 0; i < js.j_jobslots; i++) jobs[i] = (JOB *)NULL; js.j_firstj = js.j_lastj = js.j_njobs = 0; } /* Scan from the last slot backward, looking for the next free one. */ /* XXX - revisit this interactive assumption */ /* XXX - this way for now */ if (interactive) { for (i = js.j_jobslots; i; i--) if (jobs[i - 1]) break; } else { #if 0 /* This wraps around, but makes it inconvenient to extend the array */ for (i = js.j_lastj+1; i != js.j_lastj; i++) { if (i >= js.j_jobslots) i = 0; if (jobs[i] == 0) break; } if (i == js.j_lastj) i = js.j_jobslots; #else /* This doesn't wrap around yet. */ for (i = js.j_lastj ? js.j_lastj + 1 : js.j_lastj; i < js.j_jobslots; i++) if (jobs[i] == 0) break; #endif } /* Do we need more room? */ /* First try compaction */ if ((interactive_shell == 0 || subshell_environment) && i == js.j_jobslots && js.j_jobslots >= MAX_JOBS_IN_ARRAY) i = compact_jobs_list (0); /* If we can't compact, reallocate */ if (i == js.j_jobslots) { js.j_jobslots += JOB_SLOTS; jobs = (JOB **)xrealloc (jobs, (js.j_jobslots * sizeof (JOB *))); for (j = i; j < js.j_jobslots; j++) jobs[j] = (JOB *)NULL; } /* Add the current pipeline to the job list. */ if (the_pipeline) { register PROCESS *p; int any_running, any_stopped, n; newjob = (JOB *)xmalloc (sizeof (JOB)); for (n = 1, p = the_pipeline; p->next != the_pipeline; n++, p = p->next) ; p->next = (PROCESS *)NULL; newjob->pipe = REVERSE_LIST (the_pipeline, PROCESS *); for (p = newjob->pipe; p->next; p = p->next) ; p->next = newjob->pipe; the_pipeline = (PROCESS *)NULL; newjob->pgrp = pipeline_pgrp; /* Invariant: if the shell is executing a command substitution, pipeline_pgrp == shell_pgrp. Other parts of the shell assume this. */ if (pipeline_pgrp != shell_pgrp) pipeline_pgrp = 0; newjob->flags = 0; if (pipefail_opt) newjob->flags |= J_PIPEFAIL; /* Flag to see if in another pgrp. */ if (job_control) newjob->flags |= J_JOBCONTROL; /* Set the state of this pipeline. */ p = newjob->pipe; any_running = any_stopped = 0; do { any_running |= PRUNNING (p); any_stopped |= PSTOPPED (p); p = p->next; } while (p != newjob->pipe); newjob->state = any_running ? JRUNNING : (any_stopped ? JSTOPPED : JDEAD); newjob->wd = job_working_directory (); newjob->deferred = deferred; newjob->j_cleanup = (sh_vptrfunc_t *)NULL; newjob->cleanarg = (PTR_T) NULL; jobs[i] = newjob; if (newjob->state == JDEAD && (newjob->flags & J_FOREGROUND)) setjstatus (i); if (newjob->state == JDEAD) { js.c_reaped += n; /* wouldn't have been done since this was not part of a job */ js.j_ndead++; } js.c_injobs += n; js.j_lastj = i; js.j_njobs++; } else newjob = (JOB *)NULL; if (newjob) js.j_lastmade = newjob; if (async) { if (newjob) { newjob->flags &= ~J_FOREGROUND; newjob->flags |= J_ASYNC; js.j_lastasync = newjob; } reset_current (); } else { if (newjob) { newjob->flags |= J_FOREGROUND; /* * !!!!! NOTE !!!!! (chet@po.cwru.edu) * * The currently-accepted job control wisdom says to set the * terminal's process group n+1 times in an n-step pipeline: * once in the parent and once in each child. This is where * the parent gives it away. * * Don't give the terminal away if this shell is an asynchronous * subshell or if we're a (presumably non-interactive) shell running * in the background. * */ if (job_control && newjob->pgrp && (subshell_environment&SUBSHELL_ASYNC) == 0 && running_in_background == 0) maybe_give_terminal_to (shell_pgrp, newjob->pgrp, 0); } } stop_making_children (); UNBLOCK_CHILD (oset); return (newjob ? i : js.j_current); } /* Functions to manage the list of exited background pids whose status has been saved. pidstat_table: The current implementation is a hash table using a single (separate) arena for storage that can be allocated and freed as a unit. The size of the hash table is a multiple of PIDSTAT_TABLE_SZ (4096) and multiple PIDs that hash to the same value are chained through the bucket_next and bucket_prev pointers (basically coalesced hashing for collision resolution). bgpids.storage: All pid/status storage is done using the circular buffer bgpids.storage. This must contain at least js.c_childmax entries. The circular buffer is used to supply the ordered list Posix requires ("the last CHILD_MAX processes"). To avoid searching the entire storage table for a given PID, the hash table (pidstat_table) holds pointers into the storage arena and uses a doubly-linked list of cells (bucket_next/bucket_prev, also pointers into the arena) to implement collision resolution. */ /* The number of elements in bgpids.storage always has to be > js.c_childmax for the circular buffer to work right. */ static void bgp_resize () { ps_index_t nsize, nsize_cur, nsize_max; ps_index_t psi; if (bgpids.nalloc == 0) { /* invalidate hash table when bgpids table is reallocated */ for (psi = 0; psi < PIDSTAT_TABLE_SZ; psi++) pidstat_table[psi] = NO_PIDSTAT; nsize = BGPIDS_TABLE_SZ; /* should be power of 2 */ bgpids.head = 0; } else nsize = bgpids.nalloc; nsize_max = TYPE_MAXIMUM (ps_index_t); nsize_cur = (ps_index_t)js.c_childmax; if (nsize_cur < 0) /* overflow */ nsize_cur = MAX_CHILD_MAX; while (nsize > 0 && nsize < nsize_cur) /* > 0 should catch overflow */ nsize <<= 1; if (nsize > nsize_max || nsize <= 0) /* overflow? */ nsize = nsize_max; if (nsize > MAX_CHILD_MAX) nsize = nsize_max = MAX_CHILD_MAX; /* hard cap */ if (bgpids.nalloc < nsize_cur && bgpids.nalloc < nsize_max) { bgpids.storage = (struct pidstat *)xrealloc (bgpids.storage, nsize * sizeof (struct pidstat)); for (psi = bgpids.nalloc; psi < nsize; psi++) bgpids.storage[psi].pid = NO_PID; bgpids.nalloc = nsize; } else if (bgpids.head >= bgpids.nalloc) /* wrap around */ bgpids.head = 0; } static ps_index_t bgp_getindex () { if (bgpids.nalloc < (ps_index_t)js.c_childmax || bgpids.head >= bgpids.nalloc) bgp_resize (); pshash_delindex (bgpids.head); /* XXX - clear before reusing */ return bgpids.head++; } static ps_index_t * pshash_getbucket (pid) pid_t pid; { unsigned long hash; /* XXX - u_bits32_t */ hash = pid * 0x9e370001UL; return (&pidstat_table[hash % PIDSTAT_TABLE_SZ]); } static struct pidstat * bgp_add (pid, status) pid_t pid; int status; { ps_index_t *bucket, psi; struct pidstat *ps; /* bucket == existing chain of pids hashing to same value psi = where were going to put this pid/status */ bucket = pshash_getbucket (pid); /* index into pidstat_table */ psi = bgp_getindex (); /* bgpids.head, index into storage */ /* XXX - what if psi == *bucket? */ if (psi == *bucket) { internal_debug ("hashed pid %d (pid %d) collides with bgpids.head, skipping", psi, pid); bgpids.storage[psi].pid = NO_PID; /* make sure */ psi = bgp_getindex (); /* skip to next one */ } ps = &bgpids.storage[psi]; ps->pid = pid; ps->status = status; ps->bucket_next = *bucket; ps->bucket_prev = NO_PIDSTAT; bgpids.npid++; #if 0 if (bgpids.npid > js.c_childmax) bgp_prune (); #endif if (ps->bucket_next != NO_PIDSTAT) bgpids.storage[ps->bucket_next].bucket_prev = psi; *bucket = psi; /* set chain head in hash table */ return ps; } static void pshash_delindex (psi) ps_index_t psi; { struct pidstat *ps; ps_index_t *bucket; ps = &bgpids.storage[psi]; if (ps->pid == NO_PID) return; if (ps->bucket_next != NO_PIDSTAT) bgpids.storage[ps->bucket_next].bucket_prev = ps->bucket_prev; if (ps->bucket_prev != NO_PIDSTAT) bgpids.storage[ps->bucket_prev].bucket_next = ps->bucket_next; else { bucket = pshash_getbucket (ps->pid); *bucket = ps->bucket_next; /* deleting chain head in hash table */ } /* clear out this cell, in case it gets reused. */ ps->pid = NO_PID; ps->bucket_next = ps->bucket_prev = NO_PIDSTAT; } static int bgp_delete (pid) pid_t pid; { ps_index_t psi, orig_psi; if (bgpids.storage == 0 || bgpids.nalloc == 0 || bgpids.npid == 0) return 0; /* Search chain using hash to find bucket in pidstat_table */ for (orig_psi = psi = *(pshash_getbucket (pid)); psi != NO_PIDSTAT; psi = bgpids.storage[psi].bucket_next) { if (bgpids.storage[psi].pid == pid) break; if (orig_psi == bgpids.storage[psi].bucket_next) /* catch reported bug */ { internal_warning (_("bgp_delete: LOOP: psi (%d) == storage[psi].bucket_next"), psi); return 0; } } if (psi == NO_PIDSTAT) return 0; /* not found */ #if 0 itrace("bgp_delete: deleting %d", pid); #endif pshash_delindex (psi); /* hash table management */ bgpids.npid--; return 1; } /* Clear out the list of saved statuses */ static void bgp_clear () { if (bgpids.storage == 0 || bgpids.nalloc == 0) return; free (bgpids.storage); bgpids.storage = 0; bgpids.nalloc = 0; bgpids.head = 0; bgpids.npid = 0; } /* Search for PID in the list of saved background pids; return its status if found. If not found, return -1. We hash to the right spot in pidstat_table and follow the bucket chain to the end. */ static int bgp_search (pid) pid_t pid; { ps_index_t psi, orig_psi; if (bgpids.storage == 0 || bgpids.nalloc == 0 || bgpids.npid == 0) return -1; /* Search chain using hash to find bucket in pidstat_table */ for (orig_psi = psi = *(pshash_getbucket (pid)); psi != NO_PIDSTAT; psi = bgpids.storage[psi].bucket_next) { if (bgpids.storage[psi].pid == pid) return (bgpids.storage[psi].status); if (orig_psi == bgpids.storage[psi].bucket_next) /* catch reported bug */ { internal_warning (_("bgp_search: LOOP: psi (%d) == storage[psi].bucket_next"), psi); return -1; } } return -1; } #if 0 static void bgp_prune () { return; } #endif /* External interface to bgp_add; takes care of blocking and unblocking SIGCHLD. Not really used. */ void save_proc_status (pid, status) pid_t pid; int status; { sigset_t set, oset; BLOCK_CHILD (set, oset); bgp_add (pid, status); UNBLOCK_CHILD (oset); } #if defined (PROCESS_SUBSTITUTION) /* Functions to add and remove PROCESS * children from the list of running asynchronous process substitutions. The list is currently a simple singly linked list of PROCESS *, so it works with the set of callers that want a child. subst.c:process_substitute adds to the list, the various wait* functions manipulate child->running and child->status, and processes are eventually removed from the list and added to the bgpids table. */ static void procsub_free (p) PROCESS *p; { FREE (p->command); free (p); } PROCESS * procsub_add (p) PROCESS *p; { sigset_t set, oset; BLOCK_CHILD (set, oset); if (procsubs.head == 0) { procsubs.head = procsubs.end = p; procsubs.nproc = 0; } else { procsubs.end->next = p; procsubs.end = p; } procsubs.nproc++; UNBLOCK_CHILD (oset); return p; } PROCESS * procsub_search (pid) pid_t pid; { PROCESS *p; sigset_t set, oset; BLOCK_CHILD (set, oset); for (p = procsubs.head; p; p = p->next) if (p->pid == pid) break; UNBLOCK_CHILD (oset); return p; } PROCESS * procsub_delete (pid) pid_t pid; { PROCESS *p, *prev; sigset_t set, oset; BLOCK_CHILD (set, oset); for (p = prev = procsubs.head; p; prev = p, p = p->next) if (p->pid == pid) { prev->next = p->next; break; } if (p == 0) { UNBLOCK_CHILD (oset); return p; } if (p == procsubs.head) procsubs.head = procsubs.head->next; else if (p == procsubs.end) procsubs.end = prev; procsubs.nproc--; if (procsubs.nproc == 0) procsubs.head = procsubs.end = 0; else if (procsubs.nproc == 1) /* XXX */ procsubs.end = procsubs.head; /* this can't be called anywhere in a signal handling path */ bgp_add (p->pid, process_exit_status (p->status)); UNBLOCK_CHILD (oset); return (p); } int procsub_waitpid (pid) pid_t pid; { PROCESS *p; int r; p = procsub_search (pid); if (p == 0) return -1; if (p->running == PS_DONE) return (p->status); r = wait_for (p->pid, 0); return (r); /* defer removing until later */ } void procsub_waitall () { PROCESS *p; int r; for (p = procsubs.head; p; p = p->next) { if (p->running == PS_DONE) continue; r = wait_for (p->pid, 0); } } void procsub_clear () { PROCESS *p, *ps; sigset_t set, oset; BLOCK_CHILD (set, oset); for (ps = procsubs.head; ps; ) { p = ps; ps = ps->next; procsub_free (p); } procsubs.head = procsubs.end = 0; procsubs.nproc = 0; UNBLOCK_CHILD (oset); } /* Must be called with SIGCHLD blocked. */ void procsub_prune () { PROCESS *ohead, *oend, *ps, *p; int onproc; if (procsubs.nproc == 0) return; ohead = procsubs.head; oend = procsubs.end; onproc = procsubs.nproc; procsubs.head = procsubs.end = 0; procsubs.nproc = 0; for (p = ohead; p; ) { ps = p->next; p->next = 0; if (p->running == PS_DONE) { bgp_add (p->pid, process_exit_status (p->status)); procsub_free (p); } else procsub_add (p); p = ps; } } #endif /* Reset the values of js.j_lastj and js.j_firstj after one or both have been deleted. The caller should check whether js.j_njobs is 0 before calling this. This wraps around, but the rest of the code does not. At this point, it should not matter. */ static void reset_job_indices () { int old; if (jobs[js.j_firstj] == 0) { old = js.j_firstj++; if (old >= js.j_jobslots) old = js.j_jobslots - 1; while (js.j_firstj != old) { if (js.j_firstj >= js.j_jobslots) js.j_firstj = 0; if (jobs[js.j_firstj] || js.j_firstj == old) /* needed if old == 0 */ break; js.j_firstj++; } if (js.j_firstj == old) js.j_firstj = js.j_lastj = js.j_njobs = 0; } if (jobs[js.j_lastj] == 0) { old = js.j_lastj--; if (old < 0) old = 0; while (js.j_lastj != old) { if (js.j_lastj < 0) js.j_lastj = js.j_jobslots - 1; if (jobs[js.j_lastj] || js.j_lastj == old) /* needed if old == js.j_jobslots */ break; js.j_lastj--; } if (js.j_lastj == old) js.j_firstj = js.j_lastj = js.j_njobs = 0; } } /* Delete all DEAD jobs that the user had received notification about. */ static void cleanup_dead_jobs () { register int i; int os; PROCESS *discard; if (js.j_jobslots == 0 || jobs_list_frozen) return; QUEUE_SIGCHLD(os); /* XXX could use js.j_firstj and js.j_lastj here */ for (i = 0; i < js.j_jobslots; i++) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("cleanup_dead_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG(("cleanup_dead_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); if (jobs[i] && DEADJOB (i) && IS_NOTIFIED (i)) delete_job (i, 0); } #if defined (PROCESS_SUBSTITUTION) procsub_prune (); last_procsub_child = (PROCESS *)NULL; #endif #if defined (COPROCESS_SUPPORT) coproc_reap (); #endif UNQUEUE_SIGCHLD(os); } static int processes_in_job (job) int job; { int nproc; register PROCESS *p; nproc = 0; p = jobs[job]->pipe; do { p = p->next; nproc++; } while (p != jobs[job]->pipe); return nproc; } static void delete_old_job (pid) pid_t pid; { PROCESS *p; int job; job = find_job (pid, 0, &p); if (job != NO_JOB) { INTERNAL_DEBUG (("delete_old_job: found pid %d in job %d with state %d", pid, job, jobs[job]->state)); if (JOBSTATE (job) == JDEAD) delete_job (job, DEL_NOBGPID); else { internal_debug (_("forked pid %d appears in running job %d"), pid, job+1); if (p) p->pid = 0; } } } /* Reallocate and compress the jobs list. This returns with a jobs array whose size is a multiple of JOB_SLOTS and can hold the current number of jobs. Heuristics are used to minimize the number of new reallocs. */ static void realloc_jobs_list () { sigset_t set, oset; int nsize, i, j, ncur, nprev; JOB **nlist; ncur = nprev = NO_JOB; nsize = ((js.j_njobs + JOB_SLOTS - 1) / JOB_SLOTS); nsize *= JOB_SLOTS; i = js.j_njobs % JOB_SLOTS; if (i == 0 || i > (JOB_SLOTS >> 1)) nsize += JOB_SLOTS; BLOCK_CHILD (set, oset); nlist = (js.j_jobslots == nsize) ? jobs : (JOB **) xmalloc (nsize * sizeof (JOB *)); js.c_reaped = js.j_ndead = 0; for (i = j = 0; i < js.j_jobslots; i++) if (jobs[i]) { if (i == js.j_current) ncur = j; if (i == js.j_previous) nprev = j; nlist[j++] = jobs[i]; if (jobs[i]->state == JDEAD) { js.j_ndead++; js.c_reaped += processes_in_job (i); } } #if 0 itrace ("realloc_jobs_list: resize jobs list from %d to %d", js.j_jobslots, nsize); itrace ("realloc_jobs_list: j_lastj changed from %d to %d", js.j_lastj, (j > 0) ? j - 1 : 0); itrace ("realloc_jobs_list: j_njobs changed from %d to %d", js.j_njobs, j); itrace ("realloc_jobs_list: js.j_ndead %d js.c_reaped %d", js.j_ndead, js.c_reaped); #endif js.j_firstj = 0; js.j_lastj = (j > 0) ? j - 1 : 0; js.j_njobs = j; js.j_jobslots = nsize; /* Zero out remaining slots in new jobs list */ for ( ; j < nsize; j++) nlist[j] = (JOB *)NULL; if (jobs != nlist) { free (jobs); jobs = nlist; } if (ncur != NO_JOB) js.j_current = ncur; if (nprev != NO_JOB) js.j_previous = nprev; /* Need to reset these */ if (js.j_current == NO_JOB || js.j_previous == NO_JOB || js.j_current > js.j_lastj || js.j_previous > js.j_lastj) reset_current (); #if 0 itrace ("realloc_jobs_list: reset js.j_current (%d) and js.j_previous (%d)", js.j_current, js.j_previous); #endif UNBLOCK_CHILD (oset); } /* Compact the jobs list by removing dead jobs. Assume that we have filled the jobs array to some predefined maximum. Called when the shell is not the foreground process (subshell_environment != 0). Returns the first available slot in the compacted list. If that value is js.j_jobslots, then the list needs to be reallocated. The jobs array may be in new memory if this returns > 0 and < js.j_jobslots. FLAGS is reserved for future use. */ static int compact_jobs_list (flags) int flags; { if (js.j_jobslots == 0 || jobs_list_frozen) return js.j_jobslots; reap_dead_jobs (); realloc_jobs_list (); #if 0 itrace("compact_jobs_list: returning %d", (js.j_lastj || jobs[js.j_lastj]) ? js.j_lastj + 1 : 0); #endif return ((js.j_lastj || jobs[js.j_lastj]) ? js.j_lastj + 1 : 0); } /* Delete the job at INDEX from the job list. Must be called with SIGCHLD blocked. */ void delete_job (job_index, dflags) int job_index, dflags; { register JOB *temp; PROCESS *proc; int ndel; if (js.j_jobslots == 0 || jobs_list_frozen) return; if ((dflags & DEL_WARNSTOPPED) && subshell_environment == 0 && STOPPED (job_index)) internal_warning (_("deleting stopped job %d with process group %ld"), job_index+1, (long)jobs[job_index]->pgrp); temp = jobs[job_index]; if (temp == 0) return; if ((dflags & DEL_NOBGPID) == 0 && (temp->flags & (J_ASYNC|J_FOREGROUND)) == J_ASYNC) { proc = find_last_proc (job_index, 0); if (proc) bgp_add (proc->pid, process_exit_status (proc->status)); } jobs[job_index] = (JOB *)NULL; if (temp == js.j_lastmade) js.j_lastmade = 0; else if (temp == js.j_lastasync) js.j_lastasync = 0; free (temp->wd); ndel = discard_pipeline (temp->pipe); js.c_injobs -= ndel; if (temp->state == JDEAD) { /* XXX - save_pipeline and restore_pipeline (e.g., for DEBUG trap) can mess with this total. */ js.c_reaped -= ndel; /* assumes proc hadn't been reaped earlier */ js.j_ndead--; if (js.c_reaped < 0) { INTERNAL_DEBUG (("delete_job (%d pgrp %d): js.c_reaped (%d) < 0 ndel = %d js.j_ndead = %d", job_index, temp->pgrp, js.c_reaped, ndel, js.j_ndead)); js.c_reaped = 0; } } if (temp->deferred) dispose_command (temp->deferred); free (temp); js.j_njobs--; if (js.j_njobs == 0) js.j_firstj = js.j_lastj = 0; else if (jobs[js.j_firstj] == 0 || jobs[js.j_lastj] == 0) reset_job_indices (); if (job_index == js.j_current || job_index == js.j_previous) reset_current (); } /* Must be called with SIGCHLD blocked. */ void nohup_job (job_index) int job_index; { register JOB *temp; if (js.j_jobslots == 0) return; if (temp = jobs[job_index]) temp->flags |= J_NOHUP; } /* Get rid of the data structure associated with a process chain. */ int discard_pipeline (chain) register PROCESS *chain; { register PROCESS *this, *next; int n; this = chain; n = 0; do { next = this->next; FREE (this->command); free (this); n++; this = next; } while (this != chain); return n; } /* Add this process to the chain being built in the_pipeline. NAME is the command string that will be exec'ed later. PID is the process id of the child. */ static void add_process (name, pid) char *name; pid_t pid; { PROCESS *t, *p; #if defined (RECYCLES_PIDS) int j; p = find_process (pid, 0, &j); if (p) { if (j == NO_JOB) internal_debug ("add_process: process %5ld (%s) in the_pipeline", (long)p->pid, p->command); if (PALIVE (p)) internal_warning (_("add_process: pid %5ld (%s) marked as still alive"), (long)p->pid, p->command); p->running = PS_RECYCLED; /* mark as recycled */ } #endif t = (PROCESS *)xmalloc (sizeof (PROCESS)); t->next = the_pipeline; t->pid = pid; WSTATUS (t->status) = 0; t->running = PS_RUNNING; t->command = name; the_pipeline = t; if (t->next == 0) t->next = t; else { p = t->next; while (p->next != t->next) p = p->next; p->next = t; } } /* Create a (dummy) PROCESS with NAME, PID, and STATUS, and make it the last process in jobs[JID]->pipe. Used by the lastpipe code. */ void append_process (name, pid, status, jid) char *name; pid_t pid; int status; int jid; { PROCESS *t, *p; t = (PROCESS *)xmalloc (sizeof (PROCESS)); t->next = (PROCESS *)NULL; t->pid = pid; /* set process exit status using offset discovered by configure */ t->status = (status & 0xff) << WEXITSTATUS_OFFSET; t->running = PS_DONE; t->command = name; js.c_reaped++; /* XXX */ for (p = jobs[jid]->pipe; p->next != jobs[jid]->pipe; p = p->next) ; p->next = t; t->next = jobs[jid]->pipe; } #if 0 /* Take the last job and make it the first job. Must be called with SIGCHLD blocked. */ int rotate_the_pipeline () { PROCESS *p; if (the_pipeline->next == the_pipeline) return; for (p = the_pipeline; p->next != the_pipeline; p = p->next) ; the_pipeline = p; } /* Reverse the order of the processes in the_pipeline. Must be called with SIGCHLD blocked. */ int reverse_the_pipeline () { PROCESS *p, *n; if (the_pipeline->next == the_pipeline) return; for (p = the_pipeline; p->next != the_pipeline; p = p->next) ; p->next = (PROCESS *)NULL; n = REVERSE_LIST (the_pipeline, PROCESS *); the_pipeline = n; for (p = the_pipeline; p->next; p = p->next) ; p->next = the_pipeline; } #endif /* Map FUNC over the list of jobs. If FUNC returns non-zero, then it is time to stop mapping, and that is the return value for map_over_jobs. FUNC is called with a JOB, arg1, arg2, and INDEX. */ static int map_over_jobs (func, arg1, arg2) sh_job_map_func_t *func; int arg1, arg2; { register int i; int result; sigset_t set, oset; if (js.j_jobslots == 0) return 0; BLOCK_CHILD (set, oset); /* XXX could use js.j_firstj here */ for (i = result = 0; i < js.j_jobslots; i++) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("map_over_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG (("map_over_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); if (jobs[i]) { result = (*func)(jobs[i], arg1, arg2, i); if (result) break; } } UNBLOCK_CHILD (oset); return (result); } /* Cause all the jobs in the current pipeline to exit. */ void terminate_current_pipeline () { if (pipeline_pgrp && pipeline_pgrp != shell_pgrp) { killpg (pipeline_pgrp, SIGTERM); killpg (pipeline_pgrp, SIGCONT); } } /* Cause all stopped jobs to exit. */ void terminate_stopped_jobs () { register int i; /* XXX could use js.j_firstj here */ for (i = 0; i < js.j_jobslots; i++) { if (jobs[i] && STOPPED (i)) { killpg (jobs[i]->pgrp, SIGTERM); killpg (jobs[i]->pgrp, SIGCONT); } } } /* Cause all jobs, running or stopped, to receive a hangup signal. If a job is marked J_NOHUP, don't send the SIGHUP. */ void hangup_all_jobs () { register int i; /* XXX could use js.j_firstj here */ for (i = 0; i < js.j_jobslots; i++) { if (jobs[i]) { if (jobs[i]->flags & J_NOHUP) continue; killpg (jobs[i]->pgrp, SIGHUP); if (STOPPED (i)) killpg (jobs[i]->pgrp, SIGCONT); } } } void kill_current_pipeline () { stop_making_children (); start_pipeline (); } static PROCESS * find_pid_in_pipeline (pid, pipeline, alive_only) pid_t pid; PROCESS *pipeline; int alive_only; { PROCESS *p; p = pipeline; do { /* Return it if we found it. Don't ever return a recycled pid. */ if (p->pid == pid && ((alive_only == 0 && PRECYCLED(p) == 0) || PALIVE(p))) return (p); p = p->next; } while (p != pipeline); return ((PROCESS *)NULL); } /* Return the pipeline that PID belongs to. Note that the pipeline doesn't have to belong to a job. Must be called with SIGCHLD blocked. If JOBP is non-null, return the index of the job containing PID. */ static PROCESS * find_pipeline (pid, alive_only, jobp) pid_t pid; int alive_only; int *jobp; /* index into jobs list or NO_JOB */ { int job; PROCESS *p; struct pipeline_saver *save; /* See if this process is in the pipeline that we are building. */ p = (PROCESS *)NULL; if (jobp) *jobp = NO_JOB; if (the_pipeline && (p = find_pid_in_pipeline (pid, the_pipeline, alive_only))) return (p); /* Is this process in a saved pipeline? */ for (save = saved_pipeline; save; save = save->next) if (save->pipeline && (p = find_pid_in_pipeline (pid, save->pipeline, alive_only))) return (p); #if defined (PROCESS_SUBSTITUTION) if (procsubs.nproc > 0 && (p = procsub_search (pid)) && ((alive_only == 0 && PRECYCLED(p) == 0) || PALIVE(p))) return (p); #endif job = find_job (pid, alive_only, &p); if (jobp) *jobp = job; return (job == NO_JOB) ? (PROCESS *)NULL : jobs[job]->pipe; } /* Return the PROCESS * describing PID. If JOBP is non-null return the index into the jobs array of the job containing PID. Must be called with SIGCHLD blocked. */ static PROCESS * find_process (pid, alive_only, jobp) pid_t pid; int alive_only; int *jobp; /* index into jobs list or NO_JOB */ { PROCESS *p; p = find_pipeline (pid, alive_only, jobp); while (p && p->pid != pid) p = p->next; return p; } /* Return the job index that PID belongs to, or NO_JOB if it doesn't belong to any job. Must be called with SIGCHLD blocked. */ static int find_job (pid, alive_only, procp) pid_t pid; int alive_only; PROCESS **procp; { register int i; PROCESS *p; /* XXX could use js.j_firstj here, and should check js.j_lastj */ for (i = 0; i < js.j_jobslots; i++) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("find_job: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG (("find_job: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); if (jobs[i]) { p = jobs[i]->pipe; do { if (p->pid == pid && ((alive_only == 0 && PRECYCLED(p) == 0) || PALIVE(p))) { if (procp) *procp = p; return (i); } p = p->next; } while (p != jobs[i]->pipe); } } return (NO_JOB); } /* Find a job given a PID. If BLOCK is non-zero, block SIGCHLD as required by find_job. */ int get_job_by_pid (pid, block, procp) pid_t pid; int block; PROCESS **procp; { int job; sigset_t set, oset; if (block) BLOCK_CHILD (set, oset); job = find_job (pid, 0, procp); if (block) UNBLOCK_CHILD (oset); return job; } /* Print descriptive information about the job with leader pid PID. */ void describe_pid (pid) pid_t pid; { int job; sigset_t set, oset; BLOCK_CHILD (set, oset); job = find_job (pid, 0, NULL); if (job != NO_JOB) fprintf (stderr, "[%d] %ld\n", job + 1, (long)pid); else programming_error (_("describe_pid: %ld: no such pid"), (long)pid); UNBLOCK_CHILD (oset); } static char * j_strsignal (s) int s; { char *x; x = strsignal (s); if (x == 0) { x = retcode_name_buffer; snprintf (x, sizeof(retcode_name_buffer), _("Signal %d"), s); } return x; } static char * printable_job_status (j, p, format) int j; PROCESS *p; int format; { static char *temp; int es; temp = _("Done"); if (STOPPED (j) && format == 0) { if (posixly_correct == 0 || p == 0 || (WIFSTOPPED (p->status) == 0)) temp = _("Stopped"); else { temp = retcode_name_buffer; snprintf (temp, sizeof(retcode_name_buffer), _("Stopped(%s)"), signal_name (WSTOPSIG (p->status))); } } else if (RUNNING (j)) temp = _("Running"); else { if (WIFSTOPPED (p->status)) temp = j_strsignal (WSTOPSIG (p->status)); else if (WIFSIGNALED (p->status)) temp = j_strsignal (WTERMSIG (p->status)); else if (WIFEXITED (p->status)) { temp = retcode_name_buffer; es = WEXITSTATUS (p->status); if (es == 0) { strncpy (temp, _("Done"), sizeof (retcode_name_buffer) - 1); temp[sizeof (retcode_name_buffer) - 1] = '\0'; } else if (posixly_correct) snprintf (temp, sizeof(retcode_name_buffer), _("Done(%d)"), es); else snprintf (temp, sizeof(retcode_name_buffer), _("Exit %d"), es); } else temp = _("Unknown status"); } return temp; } /* This is the way to print out information on a job if you know the index. FORMAT is: JLIST_NORMAL) [1]+ Running emacs JLIST_LONG ) [1]+ 2378 Running emacs -1 ) [1]+ 2378 emacs JLIST_NORMAL) [1]+ Stopped ls | more JLIST_LONG ) [1]+ 2369 Stopped ls 2367 | more JLIST_PID_ONLY) Just list the pid of the process group leader (really the process group). JLIST_CHANGED_ONLY) Use format JLIST_NORMAL, but list only jobs about which the user has not been notified. */ /* Print status for pipeline P. If JOB_INDEX is >= 0, it is the index into the JOBS array corresponding to this pipeline. FORMAT is as described above. Must be called with SIGCHLD blocked. If you're printing a pipeline that's not in the jobs array, like the current pipeline as it's being created, pass -1 for JOB_INDEX */ static void print_pipeline (p, job_index, format, stream) PROCESS *p; int job_index, format; FILE *stream; { PROCESS *first, *last, *show; int es, name_padding; char *temp; if (p == 0) return; first = last = p; while (last->next != first) last = last->next; for (;;) { if (p != first) fprintf (stream, format ? " " : " |"); if (format != JLIST_STANDARD) fprintf (stream, "%5ld", (long)p->pid); fprintf (stream, " "); if (format > -1 && job_index >= 0) { show = format ? p : last; temp = printable_job_status (job_index, show, format); if (p != first) { if (format) { if (show->running == first->running && WSTATUS (show->status) == WSTATUS (first->status)) temp = ""; } else temp = (char *)NULL; } if (temp) { fprintf (stream, "%s", temp); es = STRLEN (temp); if (es == 0) es = 2; /* strlen ("| ") */ name_padding = LONGEST_SIGNAL_DESC - es; fprintf (stream, "%*s", name_padding, ""); if ((WIFSTOPPED (show->status) == 0) && (WIFCONTINUED (show->status) == 0) && WIFCORED (show->status)) fprintf (stream, _("(core dumped) ")); } } if (p != first && format) fprintf (stream, "| "); if (p->command) fprintf (stream, "%s", p->command); if (p == last && job_index >= 0) { temp = current_working_directory (); if (RUNNING (job_index) && (IS_FOREGROUND (job_index) == 0)) fprintf (stream, " &"); if (strcmp (temp, jobs[job_index]->wd) != 0) fprintf (stream, _(" (wd: %s)"), polite_directory_format (jobs[job_index]->wd)); } if (format || (p == last)) { /* We need to add a CR only if this is an interactive shell, and we're reporting the status of a completed job asynchronously. We can't really check whether this particular job is being reported asynchronously, so just add the CR if the shell is currently interactive and asynchronous notification is enabled. */ if (asynchronous_notification && interactive) putc ('\r', stream); fprintf (stream, "\n"); } if (p == last) break; p = p->next; } fflush (stream); } /* Print information to STREAM about jobs[JOB_INDEX] according to FORMAT. Must be called with SIGCHLD blocked or queued with queue_sigchld */ static void pretty_print_job (job_index, format, stream) int job_index, format; FILE *stream; { register PROCESS *p; /* Format only pid information about the process group leader? */ if (format == JLIST_PID_ONLY) { fprintf (stream, "%ld\n", (long)jobs[job_index]->pipe->pid); return; } if (format == JLIST_CHANGED_ONLY) { if (IS_NOTIFIED (job_index)) return; format = JLIST_STANDARD; } if (format != JLIST_NONINTERACTIVE) fprintf (stream, "[%d]%c ", job_index + 1, (job_index == js.j_current) ? '+': (job_index == js.j_previous) ? '-' : ' '); if (format == JLIST_NONINTERACTIVE) format = JLIST_LONG; p = jobs[job_index]->pipe; print_pipeline (p, job_index, format, stream); /* We have printed information about this job. When the job's status changes, waitchld () sets the notification flag to 0. */ jobs[job_index]->flags |= J_NOTIFIED; } static int print_job (job, format, state, job_index) JOB *job; int format, state, job_index; { if (state == -1 || (JOB_STATE)state == job->state) pretty_print_job (job_index, format, stdout); return (0); } void list_one_job (job, format, ignore, job_index) JOB *job; int format, ignore, job_index; { pretty_print_job (job_index, format, stdout); cleanup_dead_jobs (); } void list_stopped_jobs (format) int format; { cleanup_dead_jobs (); map_over_jobs (print_job, format, (int)JSTOPPED); } void list_running_jobs (format) int format; { cleanup_dead_jobs (); map_over_jobs (print_job, format, (int)JRUNNING); } /* List jobs. If FORMAT is non-zero, then the long form of the information is printed, else just a short version. */ void list_all_jobs (format) int format; { cleanup_dead_jobs (); map_over_jobs (print_job, format, -1); } /* Fork, handling errors. Returns the pid of the newly made child, or 0. COMMAND is just for remembering the name of the command; we don't do anything else with it. ASYNC_P says what to do with the tty. If non-zero, then don't give it away. */ pid_t make_child (command, flags) char *command; int flags; { int async_p, forksleep; sigset_t set, oset, termset, chldset, oset_copy; pid_t pid; SigHandler *oterm; sigemptyset (&oset_copy); sigprocmask (SIG_BLOCK, (sigset_t *)NULL, &oset_copy); sigaddset (&oset_copy, SIGTERM); /* Block SIGTERM here and unblock in child after fork resets the set of pending signals. */ sigemptyset (&set); sigaddset (&set, SIGCHLD); sigaddset (&set, SIGINT); sigaddset (&set, SIGTERM); sigemptyset (&oset); sigprocmask (SIG_BLOCK, &set, &oset); /* Blocked in the parent, child will receive it after unblocking SIGTERM */ if (interactive_shell) oterm = set_signal_handler (SIGTERM, SIG_DFL); making_children (); async_p = (flags & FORK_ASYNC); forksleep = 1; #if defined (BUFFERED_INPUT) /* If default_buffered_input is active, we are reading a script. If the command is asynchronous, we have already duplicated /dev/null as fd 0, but have not changed the buffered stream corresponding to the old fd 0. We don't want to sync the stream in this case. */ if (default_buffered_input != -1 && (!async_p || default_buffered_input > 0)) sync_buffered_stream (default_buffered_input); #endif /* BUFFERED_INPUT */ /* Create the child, handle severe errors. Retry on EAGAIN. */ while ((pid = fork ()) < 0 && errno == EAGAIN && forksleep < FORKSLEEP_MAX) { /* bash-4.2 */ /* keep SIGTERM blocked until we reset the handler to SIG_IGN */ sigprocmask (SIG_SETMASK, &oset_copy, (sigset_t *)NULL); /* If we can't create any children, try to reap some dead ones. */ waitchld (-1, 0); errno = EAGAIN; /* restore errno */ sys_error ("fork: retry"); if (sleep (forksleep) != 0) break; forksleep <<= 1; if (interrupt_state) break; sigprocmask (SIG_SETMASK, &set, (sigset_t *)NULL); } if (pid != 0) if (interactive_shell) set_signal_handler (SIGTERM, oterm); if (pid < 0) { sys_error ("fork"); /* Kill all of the processes in the current pipeline. */ terminate_current_pipeline (); /* Discard the current pipeline, if any. */ if (the_pipeline) kill_current_pipeline (); set_exit_status (EX_NOEXEC); throw_to_top_level (); /* Reset signals, etc. */ } if (pid == 0) { /* In the child. Give this child the right process group, set the signals to the default state for a new process. */ pid_t mypid; subshell_environment |= SUBSHELL_IGNTRAP; /* If this ends up being changed to modify or use `command' in the child process, go back and change callers who free `command' in the child process when this returns. */ mypid = getpid (); #if defined (BUFFERED_INPUT) /* Close default_buffered_input if it's > 0. We don't close it if it's 0 because that's the file descriptor used when redirecting input, and it's wrong to close the file in that case. */ unset_bash_input (0); #endif /* BUFFERED_INPUT */ CLRINTERRUPT; /* XXX - children have their own interrupt state */ /* Restore top-level signal mask, including unblocking SIGTERM */ restore_sigmask (); if (job_control) { /* All processes in this pipeline belong in the same process group. */ if (pipeline_pgrp == 0) /* This is the first child. */ pipeline_pgrp = mypid; /* Check for running command in backquotes. */ if (pipeline_pgrp == shell_pgrp) ignore_tty_job_signals (); else default_tty_job_signals (); /* Set the process group before trying to mess with the terminal's process group. This is mandated by POSIX. */ /* This is in accordance with the Posix 1003.1 standard, section B.7.2.4, which says that trying to set the terminal process group with tcsetpgrp() to an unused pgrp value (like this would have for the first child) is an error. Section B.4.3.3, p. 237 also covers this, in the context of job control shells. */ if (setpgid (mypid, pipeline_pgrp) < 0) sys_error (_("child setpgid (%ld to %ld)"), (long)mypid, (long)pipeline_pgrp); /* By convention (and assumption above), if pipeline_pgrp == shell_pgrp, we are making a child for command substitution. In this case, we don't want to give the terminal to the shell's process group (we could be in the middle of a pipeline, for example). */ if ((flags & FORK_NOTERM) == 0 && async_p == 0 && pipeline_pgrp != shell_pgrp && ((subshell_environment&(SUBSHELL_ASYNC|SUBSHELL_PIPE)) == 0) && running_in_background == 0) give_terminal_to (pipeline_pgrp, 0); #if defined (PGRP_PIPE) if (pipeline_pgrp == mypid) pipe_read (pgrp_pipe); #endif } else /* Without job control... */ { if (pipeline_pgrp == 0) pipeline_pgrp = shell_pgrp; /* If these signals are set to SIG_DFL, we encounter the curious situation of an interactive ^Z to a running process *working* and stopping the process, but being unable to do anything with that process to change its state. On the other hand, if they are set to SIG_IGN, jobs started from scripts do not stop when the shell running the script gets a SIGTSTP and stops. */ default_tty_job_signals (); } #if defined (PGRP_PIPE) /* Release the process group pipe, since our call to setpgid () is done. The last call to sh_closepipe is done in stop_pipeline. */ sh_closepipe (pgrp_pipe); #endif /* PGRP_PIPE */ /* Don't set last_asynchronous_pid in the child */ #if defined (RECYCLES_PIDS) if (last_asynchronous_pid == mypid) /* Avoid pid aliasing. 1 seems like a safe, unusual pid value. */ last_asynchronous_pid = 1; #endif } else { /* In the parent. Remember the pid of the child just created as the proper pgrp if this is the first child. */ if (job_control) { if (pipeline_pgrp == 0) { pipeline_pgrp = pid; /* Don't twiddle terminal pgrps in the parent! This is the bug, not the good thing of twiddling them in the child! */ /* give_terminal_to (pipeline_pgrp, 0); */ } /* This is done on the recommendation of the Rationale section of the POSIX 1003.1 standard, where it discusses job control and shells. It is done to avoid possible race conditions. (Ref. 1003.1 Rationale, section B.4.3.3, page 236). */ setpgid (pid, pipeline_pgrp); } else { if (pipeline_pgrp == 0) pipeline_pgrp = shell_pgrp; } /* Place all processes into the jobs array regardless of the state of job_control. */ add_process (command, pid); if (async_p) last_asynchronous_pid = pid; #if defined (RECYCLES_PIDS) else if (last_asynchronous_pid == pid) /* Avoid pid aliasing. 1 seems like a safe, unusual pid value. */ last_asynchronous_pid = 1; #endif /* Delete the saved status for any job containing this PID in case it's been reused. */ delete_old_job (pid); /* Perform the check for pid reuse unconditionally. Some systems reuse PIDs before giving a process CHILD_MAX/_SC_CHILD_MAX unique ones. */ bgp_delete (pid); /* new process, discard any saved status */ last_made_pid = pid; /* keep stats */ js.c_totforked++; js.c_living++; /* Unblock SIGTERM, SIGINT, and SIGCHLD unless creating a pipeline, in which case SIGCHLD remains blocked until all commands in the pipeline have been created (execute_cmd.c:execute_pipeline()). */ sigprocmask (SIG_SETMASK, &oset, (sigset_t *)NULL); } return (pid); } /* These two functions are called only in child processes. */ void ignore_tty_job_signals () { set_signal_handler (SIGTSTP, SIG_IGN); set_signal_handler (SIGTTIN, SIG_IGN); set_signal_handler (SIGTTOU, SIG_IGN); } /* Reset the tty-generated job control signals to SIG_DFL unless that signal was ignored at entry to the shell, in which case we need to set it to SIG_IGN in the child. We can't rely on resetting traps, since the hard ignored signals can't be trapped. */ void default_tty_job_signals () { if (signal_is_trapped (SIGTSTP) == 0 && signal_is_hard_ignored (SIGTSTP)) set_signal_handler (SIGTSTP, SIG_IGN); else set_signal_handler (SIGTSTP, SIG_DFL); if (signal_is_trapped (SIGTTIN) == 0 && signal_is_hard_ignored (SIGTTIN)) set_signal_handler (SIGTTIN, SIG_IGN); else set_signal_handler (SIGTTIN, SIG_DFL); if (signal_is_trapped (SIGTTOU) == 0 && signal_is_hard_ignored (SIGTTOU)) set_signal_handler (SIGTTOU, SIG_IGN); else set_signal_handler (SIGTTOU, SIG_DFL); } /* Called once in a parent process. */ void get_original_tty_job_signals () { static int fetched = 0; if (fetched == 0) { if (interactive_shell) { set_original_signal (SIGTSTP, SIG_DFL); set_original_signal (SIGTTIN, SIG_DFL); set_original_signal (SIGTTOU, SIG_DFL); } else { get_original_signal (SIGTSTP); get_original_signal (SIGTTIN); get_original_signal (SIGTTOU); } fetched = 1; } } /* When we end a job abnormally, or if we stop a job, we set the tty to the state kept in here. When a job ends normally, we set the state in here to the state of the tty. */ static TTYSTRUCT shell_tty_info; #if defined (NEW_TTY_DRIVER) static struct tchars shell_tchars; static struct ltchars shell_ltchars; #endif /* NEW_TTY_DRIVER */ #if defined (NEW_TTY_DRIVER) && defined (DRAIN_OUTPUT) /* Since the BSD tty driver does not allow us to change the tty modes while simultaneously waiting for output to drain and preserving typeahead, we have to drain the output ourselves before calling ioctl. We cheat by finding the length of the output queue, and using select to wait for an appropriate length of time. This is a hack, and should be labeled as such (it's a hastily-adapted mutation of a `usleep' implementation). It's only reason for existing is the flaw in the BSD tty driver. */ static int ttspeeds[] = { 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400 }; static void draino (fd, ospeed) int fd, ospeed; { register int delay = ttspeeds[ospeed]; int n; if (!delay) return; while ((ioctl (fd, TIOCOUTQ, &n) == 0) && n) { if (n > (delay / 100)) { struct timeval tv; n *= 10; /* 2 bits more for conservativeness. */ tv.tv_sec = n / delay; tv.tv_usec = ((n % delay) * 1000000) / delay; select (fd, (fd_set *)0, (fd_set *)0, (fd_set *)0, &tv); } else break; } } #endif /* NEW_TTY_DRIVER && DRAIN_OUTPUT */ /* Return the fd from which we are actually getting input. */ #define input_tty() (shell_tty != -1) ? shell_tty : fileno (stderr) /* Fill the contents of shell_tty_info with the current tty info. */ int get_tty_state () { int tty; tty = input_tty (); if (tty != -1) { #if defined (NEW_TTY_DRIVER) ioctl (tty, TIOCGETP, &shell_tty_info); ioctl (tty, TIOCGETC, &shell_tchars); ioctl (tty, TIOCGLTC, &shell_ltchars); #endif /* NEW_TTY_DRIVER */ #if defined (TERMIO_TTY_DRIVER) ioctl (tty, TCGETA, &shell_tty_info); #endif /* TERMIO_TTY_DRIVER */ #if defined (TERMIOS_TTY_DRIVER) if (tcgetattr (tty, &shell_tty_info) < 0) { #if 0 /* Only print an error message if we're really interactive at this time. */ if (interactive) sys_error ("[%ld: %d (%d)] tcgetattr", (long)getpid (), shell_level, tty); #endif return -1; } #endif /* TERMIOS_TTY_DRIVER */ if (check_window_size) get_new_window_size (0, (int *)0, (int *)0); } return 0; } /* Make the current tty use the state in shell_tty_info. */ int set_tty_state () { int tty; tty = input_tty (); if (tty != -1) { #if defined (NEW_TTY_DRIVER) # if defined (DRAIN_OUTPUT) draino (tty, shell_tty_info.sg_ospeed); # endif /* DRAIN_OUTPUT */ ioctl (tty, TIOCSETN, &shell_tty_info); ioctl (tty, TIOCSETC, &shell_tchars); ioctl (tty, TIOCSLTC, &shell_ltchars); #endif /* NEW_TTY_DRIVER */ #if defined (TERMIO_TTY_DRIVER) ioctl (tty, TCSETAW, &shell_tty_info); #endif /* TERMIO_TTY_DRIVER */ #if defined (TERMIOS_TTY_DRIVER) if (tcsetattr (tty, TCSADRAIN, &shell_tty_info) < 0) { /* Only print an error message if we're really interactive at this time. */ if (interactive) sys_error ("[%ld: %d (%d)] tcsetattr", (long)getpid (), shell_level, tty); return -1; } #endif /* TERMIOS_TTY_DRIVER */ } return 0; } /* Given an index into the jobs array JOB, return the PROCESS struct of the last process in that job's pipeline. This is the one whose exit status counts. Must be called with SIGCHLD blocked or queued. */ static PROCESS * find_last_proc (job, block) int job; int block; { register PROCESS *p; sigset_t set, oset; if (block) BLOCK_CHILD (set, oset); p = jobs[job]->pipe; while (p && p->next != jobs[job]->pipe) p = p->next; if (block) UNBLOCK_CHILD (oset); return (p); } static pid_t find_last_pid (job, block) int job; int block; { PROCESS *p; p = find_last_proc (job, block); /* Possible race condition here. */ return p->pid; } /* Wait for a particular child of the shell to finish executing. This low-level function prints an error message if PID is not a child of this shell. It returns -1 if it fails, or whatever wait_for returns otherwise. If the child is not found in the jobs table, it returns 127. If FLAGS doesn't include JWAIT_PERROR, we suppress the error message if PID isn't found. */ int wait_for_single_pid (pid, flags) pid_t pid; int flags; { register PROCESS *child; sigset_t set, oset; int r, job, alive; BLOCK_CHILD (set, oset); child = find_pipeline (pid, 0, (int *)NULL); UNBLOCK_CHILD (oset); if (child == 0) { r = bgp_search (pid); if (r >= 0) return r; } if (child == 0) { if (flags & JWAIT_PERROR) internal_error (_("wait: pid %ld is not a child of this shell"), (long)pid); return (257); } alive = 0; do { r = wait_for (pid, 0); if ((flags & JWAIT_FORCE) == 0) break; BLOCK_CHILD (set, oset); alive = PALIVE (child); UNBLOCK_CHILD (oset); } while (alive); /* POSIX.2: if we just waited for a job, we can remove it from the jobs table. */ BLOCK_CHILD (set, oset); job = find_job (pid, 0, NULL); if (job != NO_JOB && jobs[job] && DEADJOB (job)) jobs[job]->flags |= J_NOTIFIED; UNBLOCK_CHILD (oset); /* If running in posix mode, remove the job from the jobs table immediately */ if (posixly_correct) { cleanup_dead_jobs (); bgp_delete (pid); } /* Check for a trapped signal interrupting the wait builtin and jump out */ CHECK_WAIT_INTR; return r; } /* Wait for all of the background processes started by this shell to finish. */ int wait_for_background_pids (ps) struct procstat *ps; { register int i, r; int any_stopped, check_async, njobs; sigset_t set, oset; pid_t pid; for (njobs = any_stopped = 0, check_async = 1;;) { BLOCK_CHILD (set, oset); /* find first running job; if none running in foreground, break */ /* XXX could use js.j_firstj and js.j_lastj here */ for (i = 0; i < js.j_jobslots; i++) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("wait_for_background_pids: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG (("wait_for_background_pids: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); if (jobs[i] && STOPPED (i)) { builtin_warning ("job %d[%d] stopped", i+1, find_last_pid (i, 0)); any_stopped = 1; } if (jobs[i] && RUNNING (i) && IS_FOREGROUND (i) == 0) break; } if (i == js.j_jobslots) { UNBLOCK_CHILD (oset); break; } /* now wait for the last pid in that job. */ pid = find_last_pid (i, 0); UNBLOCK_CHILD (oset); QUIT; errno = 0; /* XXX */ r = wait_for_single_pid (pid, JWAIT_PERROR); if (ps) { ps->pid = pid; ps->status = (r < 0 || r > 256) ? 127 : r; } if (r == -1 && errno == ECHILD) { /* If we're mistaken about job state, compensate. */ check_async = 0; mark_all_jobs_as_dead (); } njobs++; } #if defined (PROCESS_SUBSTITUTION) procsub_waitall (); #endif /* POSIX.2 says the shell can discard the statuses of all completed jobs if `wait' is called with no arguments. */ mark_dead_jobs_as_notified (1); cleanup_dead_jobs (); bgp_clear (); return njobs; } /* Make OLD_SIGINT_HANDLER the SIGINT signal handler. */ #define INVALID_SIGNAL_HANDLER (SigHandler *)wait_for_background_pids static SigHandler *old_sigint_handler = INVALID_SIGNAL_HANDLER; static int wait_sigint_received; static int child_caught_sigint; int waiting_for_child; /* Clean up state after longjmp to wait_intr_buf */ void wait_sigint_cleanup () { queue_sigchld = 0; waiting_for_child = 0; restore_sigint_handler (); } static void restore_sigint_handler () { if (old_sigint_handler != INVALID_SIGNAL_HANDLER) { set_signal_handler (SIGINT, old_sigint_handler); old_sigint_handler = INVALID_SIGNAL_HANDLER; waiting_for_child = 0; } } /* Handle SIGINT while we are waiting for children in a script to exit. The `wait' builtin should be interruptible, but all others should be effectively ignored (i.e. not cause the shell to exit). */ static sighandler wait_sigint_handler (sig) int sig; { SigHandler *sigint_handler; if (this_shell_builtin && this_shell_builtin == wait_builtin) { set_exit_status (128+SIGINT); restore_sigint_handler (); /* If we got a SIGINT while in `wait', and SIGINT is trapped, do what POSIX.2 says (see builtins/wait.def for more info). */ if (this_shell_builtin && this_shell_builtin == wait_builtin && signal_is_trapped (SIGINT) && ((sigint_handler = trap_to_sighandler (SIGINT)) == trap_handler)) { trap_handler (SIGINT); /* set pending_traps[SIGINT] */ wait_signal_received = SIGINT; if (wait_intr_flag) sh_longjmp (wait_intr_buf, 1); else /* Let CHECK_WAIT_INTR handle it in wait_for/waitchld */ SIGRETURN (0); } else /* wait_builtin but signal not trapped, treat as interrupt */ kill (getpid (), SIGINT); } /* XXX - should this be interrupt_state? If it is, the shell will act as if it got the SIGINT interrupt. */ if (waiting_for_child) wait_sigint_received = 1; else { set_exit_status (128+SIGINT); restore_sigint_handler (); kill (getpid (), SIGINT); } /* Otherwise effectively ignore the SIGINT and allow the running job to be killed. */ SIGRETURN (0); } static int process_exit_signal (status) WAIT status; { return (WIFSIGNALED (status) ? WTERMSIG (status) : 0); } static int process_exit_status (status) WAIT status; { if (WIFSIGNALED (status)) return (128 + WTERMSIG (status)); else if (WIFSTOPPED (status) == 0) return (WEXITSTATUS (status)); else return (EXECUTION_SUCCESS); } static WAIT job_signal_status (job) int job; { register PROCESS *p; WAIT s; p = jobs[job]->pipe; do { s = p->status; if (WIFSIGNALED(s) || WIFSTOPPED(s)) break; p = p->next; } while (p != jobs[job]->pipe); return s; } /* Return the exit status of the last process in the pipeline for job JOB. This is the exit status of the entire job. */ static WAIT raw_job_exit_status (job) int job; { register PROCESS *p; int fail; WAIT ret; if (jobs[job]->flags & J_PIPEFAIL) { fail = 0; p = jobs[job]->pipe; do { if (WSTATUS (p->status) != EXECUTION_SUCCESS) fail = WSTATUS(p->status); p = p->next; } while (p != jobs[job]->pipe); WSTATUS (ret) = fail; return ret; } for (p = jobs[job]->pipe; p->next != jobs[job]->pipe; p = p->next) ; return (p->status); } /* Return the exit status of job JOB. This is the exit status of the last (rightmost) process in the job's pipeline, modified if the job was killed by a signal or stopped. */ int job_exit_status (job) int job; { return (process_exit_status (raw_job_exit_status (job))); } int job_exit_signal (job) int job; { return (process_exit_signal (raw_job_exit_status (job))); } #define FIND_CHILD(pid, child) \ do \ { \ child = find_pipeline (pid, 0, (int *)NULL); \ if (child == 0) \ { \ give_terminal_to (shell_pgrp, 0); \ UNBLOCK_CHILD (oset); \ internal_error (_("wait_for: No record of process %ld"), (long)pid); \ restore_sigint_handler (); \ return (termination_state = 127); \ } \ } \ while (0) /* Wait for pid (one of our children) to terminate, then return the termination state. Returns 127 if PID is not found in the jobs table. Returns -1 if waitchld() returns -1, indicating that there are no unwaited-for child processes. */ int wait_for (pid, flags) pid_t pid; int flags; { int job, termination_state, r; WAIT s; register PROCESS *child; sigset_t set, oset; /* In the case that this code is interrupted, and we longjmp () out of it, we are relying on the code in throw_to_top_level () to restore the top-level signal mask. */ child = 0; BLOCK_CHILD (set, oset); /* Ignore interrupts while waiting for a job run without job control to finish. We don't want the shell to exit if an interrupt is received, only if one of the jobs run is killed via SIGINT. If job control is not set, the job will be run in the same pgrp as the shell, and the shell will see any signals the job gets. In fact, we want this set every time the waiting shell and the waited- for process are in the same process group, including command substitution. */ /* This is possibly a race condition -- should it go in stop_pipeline? */ wait_sigint_received = child_caught_sigint = 0; if (job_control == 0 || (subshell_environment&SUBSHELL_COMSUB)) { SigHandler *temp_sigint_handler; temp_sigint_handler = set_signal_handler (SIGINT, wait_sigint_handler); if (temp_sigint_handler == wait_sigint_handler) internal_debug ("wait_for: recursively setting old_sigint_handler to wait_sigint_handler: running_trap = %d", running_trap); else old_sigint_handler = temp_sigint_handler; waiting_for_child = 0; if (old_sigint_handler == SIG_IGN) set_signal_handler (SIGINT, old_sigint_handler); } termination_state = last_command_exit_value; if (interactive && job_control == 0) QUIT; /* Check for terminating signals and exit the shell if we receive one */ CHECK_TERMSIG; /* Check for a trapped signal interrupting the wait builtin and jump out */ CHECK_WAIT_INTR; /* If we say wait_for (), then we have a record of this child somewhere. If it and none of its peers are running, don't call waitchld(). */ job = NO_JOB; do { if (pid != ANY_PID) FIND_CHILD (pid, child); /* If this child is part of a job, then we are really waiting for the job to finish. Otherwise, we are waiting for the child to finish. We check for JDEAD in case the job state has been set by waitchld after receipt of a SIGCHLD. */ if (job == NO_JOB && pid != ANY_PID) /* XXX -- && pid != ANY_PID ? */ job = find_job (pid, 0, NULL); /* waitchld() takes care of setting the state of the job. If the job has already exited before this is called, sigchld_handler will have called waitchld and the state will be set to JDEAD. */ if (pid == ANY_PID || PRUNNING(child) || (job != NO_JOB && RUNNING (job))) { int old_waiting; queue_sigchld = 1; old_waiting = waiting_for_child; waiting_for_child = 1; /* XXX - probably not strictly necessary but we want to catch everything that happened before we switch the behavior of trap_handler to longjmp on a trapped signal (waiting_for_child) */ CHECK_WAIT_INTR; r = waitchld (pid, 1); /* XXX */ waiting_for_child = old_waiting; #if 0 itrace("wait_for: blocking wait for %d returns %d child = %p", (int)pid, r, child); #endif queue_sigchld = 0; if (r == -1 && errno == ECHILD && this_shell_builtin == wait_builtin) { termination_state = -1; /* XXX - restore sigint handler here */ restore_sigint_handler (); goto wait_for_return; } /* If child is marked as running, but waitpid() returns -1/ECHILD, there is something wrong. Somewhere, wait should have returned that child's pid. Mark the child as not running and the job, if it exists, as JDEAD. */ if (r == -1 && errno == ECHILD) { if (child) { child->running = PS_DONE; WSTATUS (child->status) = 0; /* XXX -- can't find true status */ } js.c_living = 0; /* no living child processes */ if (job != NO_JOB) { jobs[job]->state = JDEAD; js.c_reaped++; js.j_ndead++; } if (pid == ANY_PID) { termination_state = -1; break; } } } /* If the shell is interactive, and job control is disabled, see if the foreground process has died due to SIGINT and jump out of the wait loop if it has. waitchld has already restored the old SIGINT signal handler. */ if (interactive && job_control == 0) QUIT; /* Check for terminating signals and exit the shell if we receive one */ CHECK_TERMSIG; /* Check for a trapped signal interrupting the wait builtin and jump out */ CHECK_WAIT_INTR; if (pid == ANY_PID) { /* XXX - could set child but we don't have a handle on what waitchld reaps. Leave termination_state alone. */ restore_sigint_handler (); goto wait_for_return; } } while (PRUNNING (child) || (job != NO_JOB && RUNNING (job))); /* Restore the original SIGINT signal handler before we return. */ restore_sigint_handler (); /* The exit state of the command is either the termination state of the child, or the termination state of the job. If a job, the status of the last child in the pipeline is the significant one. If the command or job was terminated by a signal, note that value also. */ termination_state = (job != NO_JOB) ? job_exit_status (job) : (child ? process_exit_status (child->status) : EXECUTION_SUCCESS); last_command_exit_signal = (job != NO_JOB) ? job_exit_signal (job) : (child ? process_exit_signal (child->status) : 0); /* XXX */ if ((job != NO_JOB && JOBSTATE (job) == JSTOPPED) || (child && WIFSTOPPED (child->status))) termination_state = 128 + WSTOPSIG (child->status); if (job == NO_JOB || IS_JOBCONTROL (job)) { /* XXX - under what circumstances is a job not present in the jobs table (job == NO_JOB)? 1. command substitution In the case of command substitution, at least, it's probably not the right thing to give the terminal to the shell's process group, even though there is code in subst.c:command_substitute to work around it. Things that don't: $PROMPT_COMMAND execution process substitution */ #if 0 if (job == NO_JOB) itrace("wait_for: job == NO_JOB, giving the terminal to shell_pgrp (%ld)", (long)shell_pgrp); #endif /* Don't modify terminal pgrp if we are running in background or a subshell. Make sure subst.c:command_substitute uses the same conditions to determine whether or not it should undo this and give the terminal to pipeline_pgrp. */ if ((flags & JWAIT_NOTERM) == 0 && running_in_background == 0 && (subshell_environment & (SUBSHELL_ASYNC|SUBSHELL_PIPE)) == 0) give_terminal_to (shell_pgrp, 0); } /* If the command did not exit cleanly, or the job is just being stopped, then reset the tty state back to what it was before this command. Reset the tty state and notify the user of the job termination only if the shell is interactive. Clean up any dead jobs in either case. */ if (job != NO_JOB) { if (interactive_shell && subshell_environment == 0) { /* This used to use `child->status'. That's wrong, however, for pipelines. `child' is the first process in the pipeline. It's likely that the process we want to check for abnormal termination or stopping is the last process in the pipeline, especially if it's long-lived and the first process is short-lived. Since we know we have a job here, we can check all the processes in this job's pipeline and see if one of them stopped or terminated due to a signal. We might want to change this later to just check the last process in the pipeline. If no process exits due to a signal, S is left as the status of the last job in the pipeline. */ s = job_signal_status (job); if (WIFSIGNALED (s) || WIFSTOPPED (s)) { set_tty_state (); /* If the current job was stopped or killed by a signal, and the user has requested it, get a possibly new window size */ if (check_window_size && (job == js.j_current || IS_FOREGROUND (job))) get_new_window_size (0, (int *)0, (int *)0); } else #if defined (READLINE) /* We don't want to do this if we are running a process during programmable completion or a command bound to `bind -x'. */ if (RL_ISSTATE (RL_STATE_COMPLETING|RL_STATE_DISPATCHING|RL_STATE_TERMPREPPED) == 0) #endif get_tty_state (); /* If job control is enabled, the job was started with job control, the job was the foreground job, and it was killed by SIGINT, then print a newline to compensate for the kernel printing the ^C without a trailing newline. */ if (job_control && IS_JOBCONTROL (job) && IS_FOREGROUND (job) && WIFSIGNALED (s) && WTERMSIG (s) == SIGINT) { /* If SIGINT is not trapped and the shell is in a for, while, or until loop, act as if the shell received SIGINT as well, so the loop can be broken. This doesn't call the SIGINT signal handler; maybe it should. */ if (signal_is_trapped (SIGINT) == 0 && (loop_level || (shell_compatibility_level > 32 && executing_list))) ADDINTERRUPT; /* Call any SIGINT trap handler if the shell is running a loop, so the loop can be broken. This seems more useful and matches the behavior when the shell is running a builtin command in a loop when it is interrupted. Change ADDINTERRUPT to trap_handler (SIGINT) to run the trap without interrupting the loop. */ else if (signal_is_trapped (SIGINT) && loop_level) ADDINTERRUPT; /* If an interactive shell with job control enabled is sourcing a file, allow the interrupt to terminate the file sourcing. */ else if (interactive_shell && signal_is_trapped (SIGINT) == 0 && sourcelevel) ADDINTERRUPT; else { putchar ('\n'); fflush (stdout); } } } else if ((subshell_environment & (SUBSHELL_COMSUB|SUBSHELL_PIPE)) && wait_sigint_received) { /* If waiting for a job in a subshell started to do command substitution or to run a pipeline element that consists of something like a while loop or a for loop, simulate getting and being killed by the SIGINT to pass the status back to our parent. */ if (child_caught_sigint == 0 && signal_is_trapped (SIGINT) == 0) { UNBLOCK_CHILD (oset); old_sigint_handler = set_signal_handler (SIGINT, SIG_DFL); if (old_sigint_handler == SIG_IGN) restore_sigint_handler (); else kill (getpid (), SIGINT); } } else if (interactive_shell == 0 && subshell_environment == 0 && IS_FOREGROUND (job)) { s = job_signal_status (job); /* If we are non-interactive, but job control is enabled, and the job died due to SIGINT, pretend we got the SIGINT */ if (job_control && IS_JOBCONTROL (job) && WIFSIGNALED (s) && WTERMSIG (s) == SIGINT) { ADDINTERRUPT; /* For now */ } if (check_window_size) get_new_window_size (0, (int *)0, (int *)0); } /* Moved here from set_job_status_and_cleanup, which is in the SIGCHLD signal handler path */ if (DEADJOB (job) && IS_FOREGROUND (job) /*&& subshell_environment == 0*/) setjstatus (job); /* If this job is dead, notify the user of the status. If the shell is interactive, this will display a message on the terminal. If the shell is not interactive, make sure we turn on the notify bit so we don't get an unwanted message about the job's termination, and so delete_job really clears the slot in the jobs table. */ notify_and_cleanup (); } wait_for_return: UNBLOCK_CHILD (oset); return (termination_state); } /* Wait for the last process in the pipeline for JOB. Returns whatever wait_for returns: the last process's termination state or -1 if there are no unwaited-for child processes or an error occurs. If FLAGS includes JWAIT_FORCE, we wait for the job to terminate, no just change state */ int wait_for_job (job, flags, ps) int job, flags; struct procstat *ps; { pid_t pid; int r, state; sigset_t set, oset; BLOCK_CHILD(set, oset); state = JOBSTATE (job); if (state == JSTOPPED) internal_warning (_("wait_for_job: job %d is stopped"), job+1); pid = find_last_pid (job, 0); UNBLOCK_CHILD(oset); do { r = wait_for (pid, 0); if (r == -1 && errno == ECHILD) mark_all_jobs_as_dead (); CHECK_WAIT_INTR; if ((flags & JWAIT_FORCE) == 0) break; BLOCK_CHILD (set, oset); state = (job != NO_JOB && jobs[job]) ? JOBSTATE (job) : JDEAD; UNBLOCK_CHILD (oset); } while (state != JDEAD); /* POSIX.2: we can remove the job from the jobs table if we just waited for it. */ BLOCK_CHILD (set, oset); if (job != NO_JOB && jobs[job] && DEADJOB (job)) jobs[job]->flags |= J_NOTIFIED; UNBLOCK_CHILD (oset); if (ps) { ps->pid = pid; ps->status = (r < 0) ? 127 : r; } return r; } /* Wait for any background job started by this shell to finish. Very similar to wait_for_background_pids(). Returns the exit status of the next exiting job, -1 if there are no background jobs. The caller is responsible for translating -1 into the right return value. RPID, if non-null, gets the pid of the job's process leader. */ int wait_for_any_job (flags, ps) int flags; struct procstat *ps; { pid_t pid; int i, r; sigset_t set, oset; if (jobs_list_frozen) return -1; /* First see if there are any unnotified dead jobs that we can report on */ BLOCK_CHILD (set, oset); for (i = 0; i < js.j_jobslots; i++) { if ((flags & JWAIT_WAITING) && jobs[i] && IS_WAITING (i) == 0) continue; /* if we don't want it, skip it */ if (jobs[i] && DEADJOB (i) && IS_NOTIFIED (i) == 0) { return_job: r = job_exit_status (i); pid = find_last_pid (i, 0); if (ps) { ps->pid = pid; ps->status = r; } notify_of_job_status (); /* XXX */ delete_job (i, 0); #if defined (COPROCESS_SUPPORT) coproc_reap (); #endif UNBLOCK_CHILD (oset); return r; } } UNBLOCK_CHILD (oset); /* At this point, we have no dead jobs in the jobs table. Wait until we get one, even if it takes multiple pids exiting. */ for (;;) { /* Make sure there is a background job to wait for */ BLOCK_CHILD (set, oset); for (i = 0; i < js.j_jobslots; i++) if (jobs[i] && RUNNING (i) && IS_FOREGROUND (i) == 0) break; if (i == js.j_jobslots) { UNBLOCK_CHILD (oset); return -1; } UNBLOCK_CHILD (oset); QUIT; CHECK_TERMSIG; CHECK_WAIT_INTR; errno = 0; r = wait_for (ANY_PID, 0); /* special sentinel value for wait_for */ if (r == -1 && errno == ECHILD) mark_all_jobs_as_dead (); /* Now we see if we have any dead jobs and return the first one */ BLOCK_CHILD (set, oset); for (i = 0; i < js.j_jobslots; i++) { if ((flags & JWAIT_WAITING) && jobs[i] && IS_WAITING (i) == 0) continue; /* if we don't want it, skip it */ if (jobs[i] && DEADJOB (i)) goto return_job; } UNBLOCK_CHILD (oset); } return -1; } /* Print info about dead jobs, and then delete them from the list of known jobs. This does not actually delete jobs when the shell is not interactive, because the dead jobs are not marked as notified. */ void notify_and_cleanup () { if (jobs_list_frozen) return; if (interactive || interactive_shell == 0 || sourcelevel) notify_of_job_status (); cleanup_dead_jobs (); } /* Make dead jobs disappear from the jobs array without notification. This is used when the shell is not interactive. */ void reap_dead_jobs () { mark_dead_jobs_as_notified (0); cleanup_dead_jobs (); } /* Return the next closest (chronologically) job to JOB which is in STATE. STATE can be JSTOPPED, JRUNNING. NO_JOB is returned if there is no next recent job. */ static int most_recent_job_in_state (job, state) int job; JOB_STATE state; { register int i, result; sigset_t set, oset; BLOCK_CHILD (set, oset); for (result = NO_JOB, i = job - 1; i >= 0; i--) { if (jobs[i] && (JOBSTATE (i) == state)) { result = i; break; } } UNBLOCK_CHILD (oset); return (result); } /* Return the newest *stopped* job older than JOB, or NO_JOB if not found. */ static int job_last_stopped (job) int job; { return (most_recent_job_in_state (job, JSTOPPED)); } /* Return the newest *running* job older than JOB, or NO_JOB if not found. */ static int job_last_running (job) int job; { return (most_recent_job_in_state (job, JRUNNING)); } /* Make JOB be the current job, and make previous be useful. Must be called with SIGCHLD blocked. */ static void set_current_job (job) int job; { int candidate; if (js.j_current != job) { js.j_previous = js.j_current; js.j_current = job; } /* First choice for previous job is the old current job. */ if (js.j_previous != js.j_current && js.j_previous != NO_JOB && jobs[js.j_previous] && STOPPED (js.j_previous)) return; /* Second choice: Newest stopped job that is older than the current job. */ candidate = NO_JOB; if (STOPPED (js.j_current)) { candidate = job_last_stopped (js.j_current); if (candidate != NO_JOB) { js.j_previous = candidate; return; } } /* If we get here, there is either only one stopped job, in which case it is the current job and the previous job should be set to the newest running job, or there are only running jobs and the previous job should be set to the newest running job older than the current job. We decide on which alternative to use based on whether or not JOBSTATE(js.j_current) is JSTOPPED. */ candidate = RUNNING (js.j_current) ? job_last_running (js.j_current) : job_last_running (js.j_jobslots); if (candidate != NO_JOB) { js.j_previous = candidate; return; } /* There is only a single job, and it is both `+' and `-'. */ js.j_previous = js.j_current; } /* Make current_job be something useful, if it isn't already. */ /* Here's the deal: The newest non-running job should be `+', and the next-newest non-running job should be `-'. If there is only a single stopped job, the js.j_previous is the newest non-running job. If there are only running jobs, the newest running job is `+' and the next-newest running job is `-'. Must be called with SIGCHLD blocked. */ static void reset_current () { int candidate; if (js.j_jobslots && js.j_current != NO_JOB && jobs[js.j_current] && STOPPED (js.j_current)) candidate = js.j_current; else { candidate = NO_JOB; /* First choice: the previous job. */ if (js.j_previous != NO_JOB && jobs[js.j_previous] && STOPPED (js.j_previous)) candidate = js.j_previous; /* Second choice: the most recently stopped job. */ if (candidate == NO_JOB) candidate = job_last_stopped (js.j_jobslots); /* Third choice: the newest running job. */ if (candidate == NO_JOB) candidate = job_last_running (js.j_jobslots); } /* If we found a job to use, then use it. Otherwise, there are no jobs period. */ if (candidate != NO_JOB) set_current_job (candidate); else js.j_current = js.j_previous = NO_JOB; } /* Set up the job structures so we know the job and its processes are all running. */ static void set_job_running (job) int job; { register PROCESS *p; /* Each member of the pipeline is now running. */ p = jobs[job]->pipe; do { if (WIFSTOPPED (p->status)) p->running = PS_RUNNING; /* XXX - could be PS_STOPPED */ p = p->next; } while (p != jobs[job]->pipe); /* This means that the job is running. */ JOBSTATE (job) = JRUNNING; } /* Start a job. FOREGROUND if non-zero says to do that. Otherwise, start the job in the background. JOB is a zero-based index into JOBS. Returns -1 if it is unable to start a job, and the return status of the job otherwise. */ int start_job (job, foreground) int job, foreground; { register PROCESS *p; int already_running; sigset_t set, oset; char *wd, *s; static TTYSTRUCT save_stty; BLOCK_CHILD (set, oset); if ((subshell_environment & SUBSHELL_COMSUB) && (pipeline_pgrp == shell_pgrp)) { internal_error (_("%s: no current jobs"), this_command_name); UNBLOCK_CHILD (oset); return (-1); } if (DEADJOB (job)) { internal_error (_("%s: job has terminated"), this_command_name); UNBLOCK_CHILD (oset); return (-1); } already_running = RUNNING (job); if (foreground == 0 && already_running) { internal_error (_("%s: job %d already in background"), this_command_name, job + 1); UNBLOCK_CHILD (oset); return (0); /* XPG6/SUSv3 says this is not an error */ } wd = current_working_directory (); /* You don't know about the state of this job. Do you? */ jobs[job]->flags &= ~J_NOTIFIED; if (foreground) { set_current_job (job); jobs[job]->flags |= J_FOREGROUND; } /* Tell the outside world what we're doing. */ p = jobs[job]->pipe; if (foreground == 0) { /* POSIX.2 says `bg' doesn't give any indication about current or previous job. */ if (posixly_correct == 0) s = (job == js.j_current) ? "+ ": ((job == js.j_previous) ? "- " : " "); else s = " "; printf ("[%d]%s", job + 1, s); } do { printf ("%s%s", p->command ? p->command : "", p->next != jobs[job]->pipe? " | " : ""); p = p->next; } while (p != jobs[job]->pipe); if (foreground == 0) printf (" &"); if (strcmp (wd, jobs[job]->wd) != 0) printf (" (wd: %s)", polite_directory_format (jobs[job]->wd)); printf ("\n"); /* Run the job. */ if (already_running == 0) set_job_running (job); /* Save the tty settings before we start the job in the foreground. */ if (foreground) { get_tty_state (); save_stty = shell_tty_info; /* Give the terminal to this job. */ if (IS_JOBCONTROL (job)) give_terminal_to (jobs[job]->pgrp, 0); } else jobs[job]->flags &= ~J_FOREGROUND; /* If the job is already running, then don't bother jump-starting it. */ if (already_running == 0) { jobs[job]->flags |= J_NOTIFIED; killpg (jobs[job]->pgrp, SIGCONT); } if (foreground) { pid_t pid; int st; pid = find_last_pid (job, 0); UNBLOCK_CHILD (oset); st = wait_for (pid, 0); shell_tty_info = save_stty; set_tty_state (); return (st); } else { reset_current (); UNBLOCK_CHILD (oset); return (0); } } /* Give PID SIGNAL. This determines what job the pid belongs to (if any). If PID does belong to a job, and the job is stopped, then CONTinue the job after giving it SIGNAL. Returns -1 on failure. If GROUP is non-null, then kill the process group associated with PID. */ int kill_pid (pid, sig, group) pid_t pid; int sig, group; { register PROCESS *p; int job, result, negative; sigset_t set, oset; if (pid < -1) { pid = -pid; group = negative = 1; } else negative = 0; result = EXECUTION_SUCCESS; if (group) { BLOCK_CHILD (set, oset); p = find_pipeline (pid, 0, &job); if (job != NO_JOB) { jobs[job]->flags &= ~J_NOTIFIED; /* Kill process in backquotes or one started without job control? */ /* If we're passed a pid < -1, just call killpg and see what happens */ if (negative && jobs[job]->pgrp == shell_pgrp) result = killpg (pid, sig); /* If we're killing using job control notification, for example, without job control active, we have to do things ourselves. */ else if (jobs[job]->pgrp == shell_pgrp) /* XXX - IS_JOBCONTROL(job) == 0? */ { p = jobs[job]->pipe; do { if (PALIVE (p) == 0) continue; /* avoid pid recycling problem */ kill (p->pid, sig); if (PEXITED (p) && (sig == SIGTERM || sig == SIGHUP)) kill (p->pid, SIGCONT); p = p->next; } while (p != jobs[job]->pipe); } else { result = killpg (jobs[job]->pgrp, sig); if (p && STOPPED (job) && (sig == SIGTERM || sig == SIGHUP)) killpg (jobs[job]->pgrp, SIGCONT); /* If we're continuing a stopped job via kill rather than bg or fg, emulate the `bg' behavior. */ if (p && STOPPED (job) && (sig == SIGCONT)) { set_job_running (job); jobs[job]->flags &= ~J_FOREGROUND; jobs[job]->flags |= J_NOTIFIED; } } } else result = killpg (pid, sig); UNBLOCK_CHILD (oset); } else result = kill (pid, sig); return (result); } /* sigchld_handler () flushes at least one of the children that we are waiting for. It gets run when we have gotten a SIGCHLD signal. */ static sighandler sigchld_handler (sig) int sig; { int n, oerrno; oerrno = errno; REINSTALL_SIGCHLD_HANDLER; sigchld++; n = 0; if (queue_sigchld == 0) n = waitchld (-1, 0); errno = oerrno; SIGRETURN (n); } /* waitchld() reaps dead or stopped children. It's called by wait_for and sigchld_handler, and runs until there aren't any children terminating any more. If BLOCK is 1, this is to be a blocking wait for a single child, although an arriving SIGCHLD could cause the wait to be non-blocking. It returns the number of children reaped, or -1 if there are no unwaited-for child processes. */ static int waitchld (wpid, block) pid_t wpid; int block; { WAIT status; PROCESS *child; pid_t pid; int ind; int call_set_current, last_stopped_job, job, children_exited, waitpid_flags; static int wcontinued = WCONTINUED; /* run-time fix for glibc problem */ call_set_current = children_exited = 0; last_stopped_job = NO_JOB; do { /* We don't want to be notified about jobs stopping if job control is not active. XXX - was interactive_shell instead of job_control */ waitpid_flags = (job_control && subshell_environment == 0) ? (WUNTRACED|wcontinued) : 0; if (sigchld || block == 0) waitpid_flags |= WNOHANG; /* Check for terminating signals and exit the shell if we receive one */ CHECK_TERMSIG; /* Check for a trapped signal interrupting the wait builtin and jump out */ CHECK_WAIT_INTR; if (block == 1 && queue_sigchld == 0 && (waitpid_flags & WNOHANG) == 0) { internal_warning (_("waitchld: turning on WNOHANG to avoid indefinite block")); waitpid_flags |= WNOHANG; } pid = WAITPID (-1, &status, waitpid_flags); #if 0 if (wpid != -1 && block) itrace("waitchld: blocking waitpid returns %d", pid); #endif #if 0 if (wpid != -1) itrace("waitchld: %s waitpid returns %d", block?"blocking":"non-blocking", pid); #endif /* WCONTINUED may be rejected by waitpid as invalid even when defined */ if (wcontinued && pid < 0 && errno == EINVAL) { wcontinued = 0; continue; /* jump back to the test and retry without WCONTINUED */ } /* The check for WNOHANG is to make sure we decrement sigchld only if it was non-zero before we called waitpid. */ if (sigchld > 0 && (waitpid_flags & WNOHANG)) sigchld--; /* If waitpid returns -1 with errno == ECHILD, there are no more unwaited-for child processes of this shell. */ if (pid < 0 && errno == ECHILD) { if (children_exited == 0) return -1; else break; } #if 0 itrace("waitchld: waitpid returns %d block = %d children_exited = %d", pid, block, children_exited); #endif /* If waitpid returns 0, there are running children. If it returns -1, the only other error POSIX says it can return is EINTR. */ CHECK_TERMSIG; CHECK_WAIT_INTR; /* If waitpid returns -1/EINTR and the shell saw a SIGINT, then we assume the child has blocked or handled SIGINT. In that case, we require the child to actually die due to SIGINT to act on the SIGINT we received; otherwise we assume the child handled it and let it go. */ if (pid < 0 && errno == EINTR && wait_sigint_received) child_caught_sigint = 1; if (pid <= 0) continue; /* jumps right to the test */ /* Linux kernels appear to signal the parent but not interrupt the waitpid() (or restart it even without SA_RESTART) on SIGINT, so if we saw a SIGINT and the process exited or died due to some other signal, assume the child caught the SIGINT. */ if (wait_sigint_received && (WIFSIGNALED (status) == 0 || WTERMSIG (status) != SIGINT)) child_caught_sigint = 1; /* If the child process did die due to SIGINT, forget our assumption that it caught or otherwise handled it. */ if (WIFSIGNALED (status) && WTERMSIG (status) == SIGINT) child_caught_sigint = 0; /* children_exited is used to run traps on SIGCHLD. We don't want to run the trap if a process is just being continued. */ if (WIFCONTINUED(status) == 0) { children_exited++; js.c_living--; } /* Locate our PROCESS for this pid. */ child = find_process (pid, 1, &job); /* want living procs only */ #if defined (COPROCESS_SUPPORT) coproc_pidchk (pid, WSTATUS(status)); #endif #if defined (PROCESS_SUBSTITUTION) /* Only manipulate the list of process substitutions while SIGCHLD is blocked. We only use this as a hint that we can remove FIFOs or close file descriptors corresponding to terminated process substitutions. */ if ((ind = find_procsub_child (pid)) >= 0) set_procsub_status (ind, pid, WSTATUS (status)); #endif /* It is not an error to have a child terminate that we did not have a record of. This child could have been part of a pipeline in backquote substitution. Even so, I'm not sure child is ever non-zero. */ if (child == 0) { if (WIFEXITED (status) || WIFSIGNALED (status)) js.c_reaped++; continue; } /* Remember status, and whether or not the process is running. */ child->status = status; child->running = WIFCONTINUED(status) ? PS_RUNNING : PS_DONE; if (PEXITED (child)) { js.c_totreaped++; if (job != NO_JOB) js.c_reaped++; } if (job == NO_JOB) continue; call_set_current += set_job_status_and_cleanup (job); if (STOPPED (job)) last_stopped_job = job; else if (DEADJOB (job) && last_stopped_job == job) last_stopped_job = NO_JOB; } while ((sigchld || block == 0) && pid > (pid_t)0); /* If a job was running and became stopped, then set the current job. Otherwise, don't change a thing. */ if (call_set_current) { if (last_stopped_job != NO_JOB) set_current_job (last_stopped_job); else reset_current (); } /* Call a SIGCHLD trap handler for each child that exits, if one is set. */ if (children_exited && (signal_is_trapped (SIGCHLD) || trap_list[SIGCHLD] == (char *)IMPOSSIBLE_TRAP_HANDLER) && trap_list[SIGCHLD] != (char *)IGNORE_SIG) { if (posixly_correct && this_shell_builtin && this_shell_builtin == wait_builtin) { /* This was trap_handler (SIGCHLD) but that can lose traps if children_exited > 1 */ queue_sigchld_trap (children_exited); wait_signal_received = SIGCHLD; /* If we're in a signal handler, let CHECK_WAIT_INTR pick it up; run_pending_traps will call run_sigchld_trap later */ if (sigchld == 0 && wait_intr_flag) sh_longjmp (wait_intr_buf, 1); } /* If not in posix mode and not executing the wait builtin, queue the signal for later handling. Run the trap immediately if we are executing the wait builtin, but don't break out of `wait'. */ else if (sigchld) /* called from signal handler */ queue_sigchld_trap (children_exited); else if (signal_in_progress (SIGCHLD)) queue_sigchld_trap (children_exited); else if (trap_list[SIGCHLD] == (char *)IMPOSSIBLE_TRAP_HANDLER) queue_sigchld_trap (children_exited); else if (running_trap) queue_sigchld_trap (children_exited); else if (this_shell_builtin == wait_builtin) run_sigchld_trap (children_exited); /* XXX */ else queue_sigchld_trap (children_exited); } /* We have successfully recorded the useful information about this process that has just changed state. If we notify asynchronously, and the job that this process belongs to is no longer running, then notify the user of that fact now. */ if (asynchronous_notification && interactive && executing_builtin == 0) notify_of_job_status (); return (children_exited); } /* Set the status of JOB and perform any necessary cleanup if the job is marked as JDEAD. Currently, the cleanup activity is restricted to handling any SIGINT received while waiting for a foreground job to finish. */ static int set_job_status_and_cleanup (job) int job; { PROCESS *child; int tstatus, job_state, any_stopped, any_tstped, call_set_current; SigHandler *temp_handler; child = jobs[job]->pipe; jobs[job]->flags &= ~J_NOTIFIED; call_set_current = 0; /* * COMPUTE JOB STATUS */ /* If all children are not running, but any of them is stopped, then the job is stopped, not dead. */ job_state = any_stopped = any_tstped = 0; do { job_state |= PRUNNING (child); #if 0 if (PEXITED (child) && (WIFSTOPPED (child->status))) #else /* Only checking for WIFSTOPPED now, not for PS_DONE */ if (PSTOPPED (child)) #endif { any_stopped = 1; any_tstped |= job_control && (WSTOPSIG (child->status) == SIGTSTP); } child = child->next; } while (child != jobs[job]->pipe); /* If job_state != 0, the job is still running, so don't bother with setting the process exit status and job state unless we're transitioning from stopped to running. */ if (job_state != 0 && JOBSTATE(job) != JSTOPPED) return 0; /* * SET JOB STATUS */ /* The job is either stopped or dead. Set the state of the job accordingly. */ if (any_stopped) { jobs[job]->state = JSTOPPED; jobs[job]->flags &= ~J_FOREGROUND; call_set_current++; /* Suspending a job with SIGTSTP breaks all active loops. */ if (any_tstped && loop_level) breaking = loop_level; } else if (job_state != 0) /* was stopped, now running */ { jobs[job]->state = JRUNNING; call_set_current++; } else { jobs[job]->state = JDEAD; js.j_ndead++; #if 0 if (IS_FOREGROUND (job)) setjstatus (job); #endif /* If this job has a cleanup function associated with it, call it with `cleanarg' as the single argument, then set the function pointer to NULL so it is not inadvertently called twice. The cleanup function is responsible for deallocating cleanarg. */ if (jobs[job]->j_cleanup) { (*jobs[job]->j_cleanup) (jobs[job]->cleanarg); jobs[job]->j_cleanup = (sh_vptrfunc_t *)NULL; } } /* * CLEANUP * * Currently, we just do special things if we got a SIGINT while waiting * for a foreground job to complete */ if (JOBSTATE (job) == JDEAD) { /* If we're running a shell script and we get a SIGINT with a SIGINT trap handler, but the foreground job handles it and does not exit due to SIGINT, run the trap handler but do not otherwise act as if we got the interrupt. */ if (wait_sigint_received && interactive_shell == 0 && child_caught_sigint && IS_FOREGROUND (job) && signal_is_trapped (SIGINT)) { int old_frozen; wait_sigint_received = 0; last_command_exit_value = process_exit_status (child->status); old_frozen = jobs_list_frozen; jobs_list_frozen = 1; tstatus = maybe_call_trap_handler (SIGINT); jobs_list_frozen = old_frozen; } /* If the foreground job is killed by SIGINT when job control is not active, we need to perform some special handling. The check of wait_sigint_received is a way to determine if the SIGINT came from the keyboard (in which case the shell has already seen it, and wait_sigint_received is non-zero, because keyboard signals are sent to process groups) or via kill(2) to the foreground process by another process (or itself). If the shell did receive the SIGINT, it needs to perform normal SIGINT processing. XXX - should this change its behavior depending on whether the last command in an pipeline exited due to SIGINT, or any process in the pipeline? Right now it does this if any process in the pipeline exits due to SIGINT. */ else if (wait_sigint_received && child_caught_sigint == 0 && IS_FOREGROUND (job) && IS_JOBCONTROL (job) == 0) { int old_frozen; wait_sigint_received = 0; /* If SIGINT is trapped, set the exit status so that the trap handler can see it. */ if (signal_is_trapped (SIGINT)) last_command_exit_value = process_exit_status (child->status); /* If the signal is trapped, let the trap handler get it no matter what and simply return if the trap handler returns. maybe_call_trap_handler() may cause dead jobs to be removed from the job table because of a call to execute_command. We work around this by setting JOBS_LIST_FROZEN. */ old_frozen = jobs_list_frozen; jobs_list_frozen = 1; tstatus = maybe_call_trap_handler (SIGINT); jobs_list_frozen = old_frozen; if (tstatus == 0 && old_sigint_handler != INVALID_SIGNAL_HANDLER) { /* wait_sigint_handler () has already seen SIGINT and allowed the wait builtin to jump out. We need to call the original SIGINT handler, if necessary. If the original handler is SIG_DFL, we need to resend the signal to ourselves. */ temp_handler = old_sigint_handler; /* Bogus. If we've reset the signal handler as the result of a trap caught on SIGINT, then old_sigint_handler will point to trap_handler, which now knows nothing about SIGINT (if we reset the sighandler to the default). In this case, we have to fix things up. What a crock. */ if (temp_handler == trap_handler && signal_is_trapped (SIGINT) == 0) temp_handler = trap_to_sighandler (SIGINT); restore_sigint_handler (); if (temp_handler == SIG_DFL) termsig_handler (SIGINT); /* XXX */ else if (temp_handler != SIG_IGN) (*temp_handler) (SIGINT); } } } return call_set_current; } /* Build the array of values for the $PIPESTATUS variable from the set of exit statuses of all processes in the job J. */ static void setjstatus (j) int j; { #if defined (ARRAY_VARS) register int i; register PROCESS *p; for (i = 1, p = jobs[j]->pipe; p->next != jobs[j]->pipe; p = p->next, i++) ; i++; if (statsize < i) { pstatuses = (int *)xrealloc (pstatuses, i * sizeof (int)); statsize = i; } i = 0; p = jobs[j]->pipe; do { pstatuses[i++] = process_exit_status (p->status); p = p->next; } while (p != jobs[j]->pipe); pstatuses[i] = -1; /* sentinel */ set_pipestatus_array (pstatuses, i); #endif } void run_sigchld_trap (nchild) int nchild; { char *trap_command; int i; /* Turn off the trap list during the call to parse_and_execute () to avoid potentially infinite recursive calls. Preserve the values of last_command_exit_value, last_made_pid, and the_pipeline around the execution of the trap commands. */ trap_command = savestring (trap_list[SIGCHLD]); begin_unwind_frame ("SIGCHLD trap"); unwind_protect_int (last_command_exit_value); unwind_protect_int (last_command_exit_signal); unwind_protect_var (last_made_pid); unwind_protect_int (jobs_list_frozen); unwind_protect_pointer (the_pipeline); unwind_protect_pointer (subst_assign_varlist); unwind_protect_pointer (this_shell_builtin); unwind_protect_pointer (temporary_env); /* We have to add the commands this way because they will be run in reverse order of adding. We don't want maybe_set_sigchld_trap () to reference freed memory. */ add_unwind_protect (xfree, trap_command); add_unwind_protect (maybe_set_sigchld_trap, trap_command); subst_assign_varlist = (WORD_LIST *)NULL; the_pipeline = (PROCESS *)NULL; temporary_env = 0; /* traps should not run with temporary env */ running_trap = SIGCHLD + 1; set_impossible_sigchld_trap (); jobs_list_frozen = 1; for (i = 0; i < nchild; i++) { parse_and_execute (savestring (trap_command), "trap", SEVAL_NOHIST|SEVAL_RESETLINE|SEVAL_NOOPTIMIZE); } run_unwind_frame ("SIGCHLD trap"); running_trap = 0; } /* Function to call when you want to notify people of changes in job status. This prints out all jobs which are pending notification to stderr, and marks those printed as already notified, thus making them candidates for cleanup. */ static void notify_of_job_status () { register int job, termsig; char *dir; sigset_t set, oset; WAIT s; if (jobs == 0 || js.j_jobslots == 0) return; if (old_ttou != 0) { sigemptyset (&set); sigaddset (&set, SIGCHLD); sigaddset (&set, SIGTTOU); sigemptyset (&oset); sigprocmask (SIG_BLOCK, &set, &oset); } else queue_sigchld++; /* XXX could use js.j_firstj here */ for (job = 0, dir = (char *)NULL; job < js.j_jobslots; job++) { if (jobs[job] && IS_NOTIFIED (job) == 0) { s = raw_job_exit_status (job); termsig = WTERMSIG (s); /* POSIX.2 says we have to hang onto the statuses of at most the last CHILD_MAX background processes if the shell is running a script. If the shell is running a script, either from a file or standard input, don't print anything unless the job was killed by a signal. */ if (startup_state == 0 && WIFSIGNALED (s) == 0 && ((DEADJOB (job) && IS_FOREGROUND (job) == 0) || STOPPED (job))) continue; /* If job control is disabled, don't print the status messages. Mark dead jobs as notified so that they get cleaned up. If startup_state == 2 and subshell_environment has the SUBSHELL_COMSUB bit turned on, we were started to run a command substitution, so don't print anything. Otherwise, if the shell is not interactive, POSIX says that `jobs' is the only way to notify of job status. */ if ((job_control == 0 && interactive_shell) || (startup_state == 2 && (subshell_environment & SUBSHELL_COMSUB)) || (startup_state == 2 && posixly_correct && (subshell_environment & SUBSHELL_COMSUB) == 0)) { /* POSIX.2 compatibility: if the shell is not interactive, hang onto the job corresponding to the last asynchronous pid until the user has been notified of its status or does a `wait'. */ if (DEADJOB (job) && (interactive_shell || (find_last_pid (job, 0) != last_asynchronous_pid))) jobs[job]->flags |= J_NOTIFIED; continue; } /* Print info on jobs that are running in the background, and on foreground jobs that were killed by anything except SIGINT (and possibly SIGPIPE). */ switch (JOBSTATE (job)) { case JDEAD: if (interactive_shell == 0 && termsig && WIFSIGNALED (s) && termsig != SIGINT && #if defined (DONT_REPORT_SIGTERM) termsig != SIGTERM && #endif #if defined (DONT_REPORT_SIGPIPE) termsig != SIGPIPE && #endif signal_is_trapped (termsig) == 0) { /* Don't print `0' for a line number. */ fprintf (stderr, _("%s: line %d: "), get_name_for_error (), (line_number == 0) ? 1 : line_number); pretty_print_job (job, JLIST_NONINTERACTIVE, stderr); } else if (IS_FOREGROUND (job)) { #if !defined (DONT_REPORT_SIGPIPE) if (termsig && WIFSIGNALED (s) && termsig != SIGINT) #else if (termsig && WIFSIGNALED (s) && termsig != SIGINT && termsig != SIGPIPE) #endif { fprintf (stderr, "%s", j_strsignal (termsig)); if (WIFCORED (s)) fprintf (stderr, _(" (core dumped)")); fprintf (stderr, "\n"); } } else if (job_control) /* XXX job control test added */ { if (dir == 0) dir = current_working_directory (); pretty_print_job (job, JLIST_STANDARD, stderr); if (dir && strcmp (dir, jobs[job]->wd) != 0) fprintf (stderr, _("(wd now: %s)\n"), polite_directory_format (dir)); } jobs[job]->flags |= J_NOTIFIED; break; case JSTOPPED: fprintf (stderr, "\n"); if (dir == 0) dir = current_working_directory (); pretty_print_job (job, JLIST_STANDARD, stderr); if (dir && (strcmp (dir, jobs[job]->wd) != 0)) fprintf (stderr, _("(wd now: %s)\n"), polite_directory_format (dir)); jobs[job]->flags |= J_NOTIFIED; break; case JRUNNING: case JMIXED: break; default: programming_error ("notify_of_job_status"); } } } if (old_ttou != 0) sigprocmask (SIG_SETMASK, &oset, (sigset_t *)NULL); else queue_sigchld--; } /* Initialize the job control mechanism, and set up the tty stuff. */ int initialize_job_control (force) int force; { pid_t t; int t_errno, tty_sigs; t_errno = -1; shell_pgrp = getpgid (0); if (shell_pgrp == -1) { sys_error (_("initialize_job_control: getpgrp failed")); exit (1); } /* We can only have job control if we are interactive unless we force it. */ if (interactive == 0 && force == 0) { job_control = 0; original_pgrp = NO_PID; shell_tty = fileno (stderr); terminal_pgrp = tcgetpgrp (shell_tty); /* for checking later */ } else { shell_tty = -1; /* If forced_interactive is set, we skip the normal check that stderr is attached to a tty, so we need to check here. If it's not, we need to see whether we have a controlling tty by opening /dev/tty, since trying to use job control tty pgrp manipulations on a non-tty is going to fail. */ if (forced_interactive && isatty (fileno (stderr)) == 0) shell_tty = open ("/dev/tty", O_RDWR|O_NONBLOCK); /* Get our controlling terminal. If job_control is set, or interactive is set, then this is an interactive shell no matter where fd 2 is directed. */ if (shell_tty == -1) shell_tty = dup (fileno (stderr)); /* fd 2 */ if (shell_tty != -1) shell_tty = move_to_high_fd (shell_tty, 1, -1); /* Compensate for a bug in systems that compiled the BSD rlogind with DEBUG defined, like NeXT and Alliant. */ if (shell_pgrp == 0) { shell_pgrp = getpid (); setpgid (0, shell_pgrp); if (shell_tty != -1) tcsetpgrp (shell_tty, shell_pgrp); } tty_sigs = 0; while ((terminal_pgrp = tcgetpgrp (shell_tty)) != -1) { if (shell_pgrp != terminal_pgrp) { SigHandler *ottin; CHECK_TERMSIG; ottin = set_signal_handler (SIGTTIN, SIG_DFL); kill (0, SIGTTIN); set_signal_handler (SIGTTIN, ottin); if (tty_sigs++ > 16) { sys_error (_("initialize_job_control: no job control in background")); job_control = 0; original_pgrp = terminal_pgrp; /* for eventual give_terminal_to */ goto just_bail; } continue; } break; } if (terminal_pgrp == -1) t_errno = errno; /* Make sure that we are using the new line discipline. */ if (set_new_line_discipline (shell_tty) < 0) { sys_error (_("initialize_job_control: line discipline")); job_control = 0; } else { original_pgrp = shell_pgrp; shell_pgrp = getpid (); if ((original_pgrp != shell_pgrp) && (setpgid (0, shell_pgrp) < 0)) { sys_error (_("initialize_job_control: setpgid")); shell_pgrp = original_pgrp; } job_control = 1; /* If (and only if) we just set our process group to our pid, thereby becoming a process group leader, and the terminal is not in the same process group as our (new) process group, then set the terminal's process group to our (new) process group. If that fails, set our process group back to what it was originally (so we can still read from the terminal) and turn off job control. */ if (shell_pgrp != original_pgrp && shell_pgrp != terminal_pgrp) { if (give_terminal_to (shell_pgrp, 0) < 0) { t_errno = errno; setpgid (0, original_pgrp); shell_pgrp = original_pgrp; errno = t_errno; sys_error (_("cannot set terminal process group (%d)"), shell_pgrp); job_control = 0; } } if (job_control && ((t = tcgetpgrp (shell_tty)) == -1 || t != shell_pgrp)) { if (t_errno != -1) errno = t_errno; sys_error (_("cannot set terminal process group (%d)"), t); job_control = 0; } } if (job_control == 0) internal_error (_("no job control in this shell")); } just_bail: running_in_background = terminal_pgrp != shell_pgrp; if (shell_tty != fileno (stderr)) SET_CLOSE_ON_EXEC (shell_tty); set_signal_handler (SIGCHLD, sigchld_handler); change_flag ('m', job_control ? '-' : '+'); if (interactive) get_tty_state (); set_maxchild (0); return job_control; } #ifdef DEBUG void debug_print_pgrps () { itrace("original_pgrp = %ld shell_pgrp = %ld terminal_pgrp = %ld", (long)original_pgrp, (long)shell_pgrp, (long)terminal_pgrp); itrace("tcgetpgrp(%d) -> %ld, getpgid(0) -> %ld", shell_tty, (long)tcgetpgrp (shell_tty), (long)getpgid(0)); itrace("pipeline_pgrp -> %ld", (long)pipeline_pgrp); } #endif /* Set the line discipline to the best this system has to offer. Return -1 if this is not possible. */ static int set_new_line_discipline (tty) int tty; { #if defined (NEW_TTY_DRIVER) int ldisc; if (ioctl (tty, TIOCGETD, &ldisc) < 0) return (-1); if (ldisc != NTTYDISC) { ldisc = NTTYDISC; if (ioctl (tty, TIOCSETD, &ldisc) < 0) return (-1); } return (0); #endif /* NEW_TTY_DRIVER */ #if defined (TERMIO_TTY_DRIVER) # if defined (TERMIO_LDISC) && (NTTYDISC) if (ioctl (tty, TCGETA, &shell_tty_info) < 0) return (-1); if (shell_tty_info.c_line != NTTYDISC) { shell_tty_info.c_line = NTTYDISC; if (ioctl (tty, TCSETAW, &shell_tty_info) < 0) return (-1); } # endif /* TERMIO_LDISC && NTTYDISC */ return (0); #endif /* TERMIO_TTY_DRIVER */ #if defined (TERMIOS_TTY_DRIVER) # if defined (TERMIOS_LDISC) && defined (NTTYDISC) if (tcgetattr (tty, &shell_tty_info) < 0) return (-1); if (shell_tty_info.c_line != NTTYDISC) { shell_tty_info.c_line = NTTYDISC; if (tcsetattr (tty, TCSADRAIN, &shell_tty_info) < 0) return (-1); } # endif /* TERMIOS_LDISC && NTTYDISC */ return (0); #endif /* TERMIOS_TTY_DRIVER */ #if !defined (NEW_TTY_DRIVER) && !defined (TERMIO_TTY_DRIVER) && !defined (TERMIOS_TTY_DRIVER) return (-1); #endif } /* Setup this shell to handle C-C, etc. */ void initialize_job_signals () { if (interactive) { set_signal_handler (SIGINT, sigint_sighandler); set_signal_handler (SIGTSTP, SIG_IGN); set_signal_handler (SIGTTOU, SIG_IGN); set_signal_handler (SIGTTIN, SIG_IGN); } else if (job_control) { old_tstp = set_signal_handler (SIGTSTP, sigstop_sighandler); old_ttin = set_signal_handler (SIGTTIN, sigstop_sighandler); old_ttou = set_signal_handler (SIGTTOU, sigstop_sighandler); } /* Leave disposition unmodified for non-interactive shells without job control. */ } /* Here we handle CONT signals. */ static sighandler sigcont_sighandler (sig) int sig; { initialize_job_signals (); set_signal_handler (SIGCONT, old_cont); kill (getpid (), SIGCONT); SIGRETURN (0); } /* Here we handle stop signals while we are running not as a login shell. */ static sighandler sigstop_sighandler (sig) int sig; { set_signal_handler (SIGTSTP, old_tstp); set_signal_handler (SIGTTOU, old_ttou); set_signal_handler (SIGTTIN, old_ttin); old_cont = set_signal_handler (SIGCONT, sigcont_sighandler); give_terminal_to (shell_pgrp, 0); kill (getpid (), sig); SIGRETURN (0); } /* Give the terminal to PGRP. */ int give_terminal_to (pgrp, force) pid_t pgrp; int force; { sigset_t set, oset; int r, e; r = 0; if (job_control || force) { sigemptyset (&set); sigaddset (&set, SIGTTOU); sigaddset (&set, SIGTTIN); sigaddset (&set, SIGTSTP); sigaddset (&set, SIGCHLD); sigemptyset (&oset); sigprocmask (SIG_BLOCK, &set, &oset); if (tcsetpgrp (shell_tty, pgrp) < 0) { /* Maybe we should print an error message? */ #if 0 sys_error ("tcsetpgrp(%d) failed: pid %ld to pgrp %ld", shell_tty, (long)getpid(), (long)pgrp); #endif r = -1; e = errno; } else terminal_pgrp = pgrp; sigprocmask (SIG_SETMASK, &oset, (sigset_t *)NULL); } if (r == -1) errno = e; return r; } /* Give terminal to NPGRP iff it's currently owned by OPGRP. FLAGS are the flags to pass to give_terminal_to(). */ static int maybe_give_terminal_to (opgrp, npgrp, flags) pid_t opgrp, npgrp; int flags; { int tpgrp; tpgrp = tcgetpgrp (shell_tty); if (tpgrp < 0 && errno == ENOTTY) return -1; if (tpgrp == npgrp) { terminal_pgrp = npgrp; return 0; } else if (tpgrp != opgrp) { internal_debug ("%d: maybe_give_terminal_to: terminal pgrp == %d shell pgrp = %d new pgrp = %d in_background = %d", (int)getpid(), tpgrp, opgrp, npgrp, running_in_background); return -1; } else return (give_terminal_to (npgrp, flags)); } /* Clear out any jobs in the job array. This is intended to be used by children of the shell, who should not have any job structures as baggage when they start executing (forking subshells for parenthesized execution and functions with pipes are the two that spring to mind). If RUNNING_ONLY is nonzero, only running jobs are removed from the table. */ void delete_all_jobs (running_only) int running_only; { register int i; sigset_t set, oset; BLOCK_CHILD (set, oset); /* XXX - need to set j_lastj, j_firstj appropriately if running_only != 0. */ if (js.j_jobslots) { js.j_current = js.j_previous = NO_JOB; /* XXX could use js.j_firstj here */ for (i = 0; i < js.j_jobslots; i++) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("delete_all_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG (("delete_all_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); if (jobs[i] && (running_only == 0 || (running_only && RUNNING(i)))) /* We don't want to add any of these pids to bgpids. If running_only is non-zero, we don't want to add running jobs to the list. If we are interested in all jobs, not just running jobs, and we are going to clear the bgpids list below (bgp_clear()), we don't need to bother. */ delete_job (i, DEL_WARNSTOPPED|DEL_NOBGPID); } if (running_only == 0) { free ((char *)jobs); js.j_jobslots = 0; js.j_firstj = js.j_lastj = js.j_njobs = 0; } } if (running_only == 0) bgp_clear (); UNBLOCK_CHILD (oset); } /* Mark all jobs in the job array so that they don't get a SIGHUP when the shell gets one. If RUNNING_ONLY is nonzero, mark only running jobs. */ void nohup_all_jobs (running_only) int running_only; { register int i; sigset_t set, oset; BLOCK_CHILD (set, oset); if (js.j_jobslots) { /* XXX could use js.j_firstj here */ for (i = 0; i < js.j_jobslots; i++) if (jobs[i] && (running_only == 0 || (running_only && RUNNING(i)))) nohup_job (i); } UNBLOCK_CHILD (oset); } int count_all_jobs () { int i, n; sigset_t set, oset; /* This really counts all non-dead jobs. */ BLOCK_CHILD (set, oset); /* XXX could use js.j_firstj here */ for (i = n = 0; i < js.j_jobslots; i++) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("count_all_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG (("count_all_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); if (jobs[i] && DEADJOB(i) == 0) n++; } UNBLOCK_CHILD (oset); return n; } static void mark_all_jobs_as_dead () { register int i; sigset_t set, oset; if (js.j_jobslots == 0) return; BLOCK_CHILD (set, oset); /* XXX could use js.j_firstj here */ for (i = 0; i < js.j_jobslots; i++) if (jobs[i]) { jobs[i]->state = JDEAD; js.j_ndead++; } UNBLOCK_CHILD (oset); } /* Mark all dead jobs as notified, so delete_job () cleans them out of the job table properly. POSIX.2 says we need to save the status of the last CHILD_MAX jobs, so we count the number of dead jobs and mark only enough as notified to save CHILD_MAX statuses. */ static void mark_dead_jobs_as_notified (force) int force; { register int i, ndead, ndeadproc; sigset_t set, oset; if (js.j_jobslots == 0) return; BLOCK_CHILD (set, oset); /* If FORCE is non-zero, we don't have to keep CHILD_MAX statuses around; just run through the array. */ if (force) { /* XXX could use js.j_firstj here */ for (i = 0; i < js.j_jobslots; i++) { if (jobs[i] && DEADJOB (i) && (interactive_shell || (find_last_pid (i, 0) != last_asynchronous_pid))) jobs[i]->flags |= J_NOTIFIED; } UNBLOCK_CHILD (oset); return; } /* Mark enough dead jobs as notified to keep CHILD_MAX processes left in the array with the corresponding not marked as notified. This is a better way to avoid pid aliasing and reuse problems than keeping the POSIX- mandated CHILD_MAX jobs around. delete_job() takes care of keeping the bgpids list regulated. */ /* Count the number of dead jobs */ /* XXX could use js.j_firstj here */ for (i = ndead = ndeadproc = 0; i < js.j_jobslots; i++) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("mark_dead_jobs_as_notified: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG (("mark_dead_jobs_as_notified: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); if (jobs[i] && DEADJOB (i)) { ndead++; ndeadproc += processes_in_job (i); } } # if 0 if (ndeadproc != js.c_reaped) itrace("mark_dead_jobs_as_notified: ndeadproc (%d) != js.c_reaped (%d)", ndeadproc, js.c_reaped); # endif if (ndead != js.j_ndead) INTERNAL_DEBUG (("mark_dead_jobs_as_notified: ndead (%d) != js.j_ndead (%d)", ndead, js.j_ndead)); if (js.c_childmax < 0) set_maxchild (0); /* Don't do anything if the number of dead processes is less than CHILD_MAX and we're not forcing a cleanup. */ if (ndeadproc <= js.c_childmax) { UNBLOCK_CHILD (oset); return; } #if 0 itrace("mark_dead_jobs_as_notified: child_max = %d ndead = %d ndeadproc = %d", js.c_childmax, ndead, ndeadproc); #endif /* Mark enough dead jobs as notified that we keep CHILD_MAX jobs in the list. This isn't exactly right yet; changes need to be made to stop_pipeline so we don't mark the newer jobs after we've created CHILD_MAX slots in the jobs array. This needs to be integrated with a way to keep the jobs array from growing without bound. Maybe we wrap back around to 0 after we reach some max limit, and there are sufficient job slots free (keep track of total size of jobs array (js.j_jobslots) and running count of number of jobs in jobs array. Then keep a job index corresponding to the `oldest job' and start this loop there, wrapping around as necessary. In effect, we turn the list into a circular buffer. */ /* XXX could use js.j_firstj here */ for (i = 0; i < js.j_jobslots; i++) { if (jobs[i] && DEADJOB (i) && (interactive_shell || (find_last_pid (i, 0) != last_asynchronous_pid))) { if (i < js.j_firstj && jobs[i]) INTERNAL_DEBUG (("mark_dead_jobs_as_notified: job %d non-null before js.j_firstj (%d)", i, js.j_firstj)); if (i > js.j_lastj && jobs[i]) INTERNAL_DEBUG (("mark_dead_jobs_as_notified: job %d non-null after js.j_lastj (%d)", i, js.j_lastj)); /* If marking this job as notified would drop us down below child_max, don't mark it so we can keep at least child_max statuses. XXX -- need to check what Posix actually says about keeping statuses. */ if ((ndeadproc -= processes_in_job (i)) <= js.c_childmax) break; jobs[i]->flags |= J_NOTIFIED; } } UNBLOCK_CHILD (oset); } /* Here to allow other parts of the shell (like the trap stuff) to freeze and unfreeze the jobs list. */ int freeze_jobs_list () { int o; o = jobs_list_frozen; jobs_list_frozen = 1; return o; } void unfreeze_jobs_list () { jobs_list_frozen = 0; } void set_jobs_list_frozen (s) int s; { jobs_list_frozen = s; } /* Allow or disallow job control to take place. Returns the old value of job_control. */ int set_job_control (arg) int arg; { int old; old = job_control; job_control = arg; if (terminal_pgrp == NO_PID && shell_tty >= 0) terminal_pgrp = tcgetpgrp (shell_tty); /* If we're turning on job control we're going to want to know the shell's process group. */ if (job_control != old && job_control) shell_pgrp = getpgid (0); running_in_background = (terminal_pgrp != shell_pgrp); #if 0 if (interactive_shell == 0 && running_in_background == 0 && job_control != old) { if (job_control) initialize_job_signals (); else default_tty_job_signals (); } #endif /* If we're turning on job control, reset pipeline_pgrp so make_child will put new child processes into the right pgrp */ if (job_control != old && job_control) pipeline_pgrp = 0; return (old); } /* Turn off all traces of job control. This is run by children of the shell which are going to do shellsy things, like wait (), etc. */ void without_job_control () { stop_making_children (); start_pipeline (); #if defined (PGRP_PIPE) sh_closepipe (pgrp_pipe); #endif delete_all_jobs (0); set_job_control (0); } /* If this shell is interactive, terminate all stopped jobs and restore the original terminal process group. This is done before the `exec' builtin calls shell_execve. */ void end_job_control () { if (job_control) terminate_stopped_jobs (); if (original_pgrp >= 0 && terminal_pgrp != original_pgrp) give_terminal_to (original_pgrp, 1); if (original_pgrp >= 0 && setpgid (0, original_pgrp) == 0) shell_pgrp = original_pgrp; } /* Restart job control by closing shell tty and reinitializing. This is called after an exec fails in an interactive shell and we do not exit. */ void restart_job_control () { if (shell_tty != -1) close (shell_tty); initialize_job_control (0); } /* Set the maximum number of background children we keep track of to NCHILD. If the caller passes NCHILD as 0 or -1, this ends up setting it to LMAXCHILD, which is initialized the first time through. */ void set_maxchild (nchild) int nchild; { static int lmaxchild = -1; /* Initialize once. */ if (lmaxchild < 0) { errno = 0; lmaxchild = getmaxchild (); if (lmaxchild < 0 && errno == 0) lmaxchild = MAX_CHILD_MAX; /* assume unlimited */ } if (lmaxchild < 0) lmaxchild = DEFAULT_CHILD_MAX; /* Clamp value we set. Minimum is what Posix requires, maximum is defined above as MAX_CHILD_MAX. */ if (nchild < lmaxchild) nchild = lmaxchild; else if (nchild > MAX_CHILD_MAX) nchild = MAX_CHILD_MAX; js.c_childmax = nchild; } /* Set the handler to run when the shell receives a SIGCHLD signal. */ void set_sigchld_handler () { set_signal_handler (SIGCHLD, sigchld_handler); } #if defined (PGRP_PIPE) /* Read from the read end of a pipe. This is how the process group leader blocks until all of the processes in a pipeline have been made. */ static void pipe_read (pp) int *pp; { char ch; if (pp[1] >= 0) { close (pp[1]); pp[1] = -1; } if (pp[0] >= 0) { while (read (pp[0], &ch, 1) == -1 && errno == EINTR) ; } } /* Functional interface closes our local-to-job-control pipes. */ void close_pgrp_pipe () { sh_closepipe (pgrp_pipe); } void save_pgrp_pipe (p, clear) int *p; int clear; { p[0] = pgrp_pipe[0]; p[1] = pgrp_pipe[1]; if (clear) pgrp_pipe[0] = pgrp_pipe[1] = -1; } void restore_pgrp_pipe (p) int *p; { pgrp_pipe[0] = p[0]; pgrp_pipe[1] = p[1]; } #endif /* PGRP_PIPE */