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Diffstat (limited to 'bin/sh/jobs.c')
| -rw-r--r-- | bin/sh/jobs.c | 1571 |
1 files changed, 1571 insertions, 0 deletions
diff --git a/bin/sh/jobs.c b/bin/sh/jobs.c new file mode 100644 index 000000000000..1328ae50edef --- /dev/null +++ b/bin/sh/jobs.c @@ -0,0 +1,1571 @@ +/*- + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Kenneth Almquist. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/ioctl.h> +#include <sys/param.h> +#include <sys/resource.h> +#include <sys/time.h> +#include <sys/wait.h> +#include <errno.h> +#include <fcntl.h> +#include <paths.h> +#include <signal.h> +#include <stddef.h> +#include <stdlib.h> +#include <unistd.h> + +#include "shell.h" +#if JOBS +#include <termios.h> +#undef CEOF /* syntax.h redefines this */ +#endif +#include "redir.h" +#include "exec.h" +#include "show.h" +#include "main.h" +#include "parser.h" +#include "nodes.h" +#include "jobs.h" +#include "options.h" +#include "trap.h" +#include "syntax.h" +#include "input.h" +#include "output.h" +#include "memalloc.h" +#include "error.h" +#include "mystring.h" +#include "var.h" +#include "builtins.h" +#include "eval.h" + + +/* + * A job structure contains information about a job. A job is either a + * single process or a set of processes contained in a pipeline. In the + * latter case, pidlist will be non-NULL, and will point to a -1 terminated + * array of pids. + */ + +struct procstat { + pid_t pid; /* process id */ + int status; /* status flags (defined above) */ + char *cmd; /* text of command being run */ +}; + + +/* states */ +#define JOBSTOPPED 1 /* all procs are stopped */ +#define JOBDONE 2 /* all procs are completed */ + + +struct job { + struct procstat ps0; /* status of process */ + struct procstat *ps; /* status or processes when more than one */ + short nprocs; /* number of processes */ + pid_t pgrp; /* process group of this job */ + char state; /* true if job is finished */ + char used; /* true if this entry is in use */ + char changed; /* true if status has changed */ + char foreground; /* true if running in the foreground */ + char remembered; /* true if $! referenced */ + char pipefail; /* pass any non-zero status */ +#if JOBS + char jobctl; /* job running under job control */ + struct job *next; /* job used after this one */ +#endif +}; + + +static struct job *jobtab; /* array of jobs */ +static int njobs; /* size of array */ +static pid_t backgndpid = -1; /* pid of last background process */ +static struct job *bgjob = NULL; /* last background process */ +#if JOBS +static struct job *jobmru; /* most recently used job list */ +static pid_t initialpgrp; /* pgrp of shell on invocation */ +#endif +static int ttyfd = -1; + +/* mode flags for dowait */ +#define DOWAIT_BLOCK 0x1 /* wait until a child exits */ +#define DOWAIT_SIG 0x2 /* if DOWAIT_BLOCK, abort on signal */ +#define DOWAIT_SIG_TRAP 0x4 /* if DOWAIT_SIG, abort on trapped signal only */ + +#if JOBS +static void restartjob(struct job *); +#endif +static void freejob(struct job *); +static int waitcmdloop(struct job *); +static struct job *getjob_nonotfound(const char *); +static struct job *getjob(const char *); +pid_t killjob(const char *, int); +static pid_t dowait(int, struct job *); +static void checkzombies(void); +static void cmdtxt(union node *); +static void cmdputs(const char *); +#if JOBS +static void setcurjob(struct job *); +static void deljob(struct job *); +static struct job *getcurjob(struct job *); +#endif +static int getjobstatus(const struct job *); +static void printjobcmd(struct job *); +static void showjob(struct job *, int); + + +/* + * Turn job control on and off. + */ + +static int jobctl; + +#if JOBS +static void +jobctl_notty(void) +{ + if (ttyfd >= 0) { + close(ttyfd); + ttyfd = -1; + } + if (!iflag) { + setsignal(SIGTSTP); + setsignal(SIGTTOU); + setsignal(SIGTTIN); + jobctl = 1; + return; + } + out2fmt_flush("sh: can't access tty; job control turned off\n"); + mflag = 0; +} + +void +setjobctl(int on) +{ + int i; + + if (on == jobctl || rootshell == 0) + return; + if (on) { + if (ttyfd != -1) + close(ttyfd); + if ((ttyfd = open(_PATH_TTY, O_RDWR | O_CLOEXEC)) < 0) { + i = 0; + while (i <= 2 && !isatty(i)) + i++; + if (i > 2 || + (ttyfd = fcntl(i, F_DUPFD_CLOEXEC, 10)) < 0) { + jobctl_notty(); + return; + } + } + if (ttyfd < 10) { + /* + * Keep our TTY file descriptor out of the way of + * the user's redirections. + */ + if ((i = fcntl(ttyfd, F_DUPFD_CLOEXEC, 10)) < 0) { + jobctl_notty(); + return; + } + close(ttyfd); + ttyfd = i; + } + do { /* while we are in the background */ + initialpgrp = tcgetpgrp(ttyfd); + if (initialpgrp < 0) { + jobctl_notty(); + return; + } + if (initialpgrp != getpgrp()) { + if (!iflag) { + initialpgrp = -1; + jobctl_notty(); + return; + } + kill(0, SIGTTIN); + continue; + } + } while (0); + setsignal(SIGTSTP); + setsignal(SIGTTOU); + setsignal(SIGTTIN); + setpgid(0, rootpid); + tcsetpgrp(ttyfd, rootpid); + } else { /* turning job control off */ + setpgid(0, initialpgrp); + if (ttyfd >= 0) { + tcsetpgrp(ttyfd, initialpgrp); + close(ttyfd); + ttyfd = -1; + } + setsignal(SIGTSTP); + setsignal(SIGTTOU); + setsignal(SIGTTIN); + } + jobctl = on; +} +#endif + + +#if JOBS +int +fgcmd(int argc __unused, char **argv __unused) +{ + struct job *jp; + pid_t pgrp; + int status; + + nextopt(""); + jp = getjob(*argptr); + if (jp->jobctl == 0) + error("job not created under job control"); + printjobcmd(jp); + flushout(&output); + pgrp = jp->ps[0].pid; + if (ttyfd >= 0) + tcsetpgrp(ttyfd, pgrp); + restartjob(jp); + jp->foreground = 1; + INTOFF; + status = waitforjob(jp, (int *)NULL); + INTON; + return status; +} + + +int +bgcmd(int argc __unused, char **argv __unused) +{ + struct job *jp; + + nextopt(""); + do { + jp = getjob(*argptr); + if (jp->jobctl == 0) + error("job not created under job control"); + if (jp->state == JOBDONE) + continue; + restartjob(jp); + jp->foreground = 0; + out1fmt("[%td] ", jp - jobtab + 1); + printjobcmd(jp); + } while (*argptr != NULL && *++argptr != NULL); + return 0; +} + + +static void +restartjob(struct job *jp) +{ + struct procstat *ps; + int i; + + if (jp->state == JOBDONE) + return; + setcurjob(jp); + INTOFF; + kill(-jp->ps[0].pid, SIGCONT); + for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { + if (WIFSTOPPED(ps->status)) { + ps->status = -1; + jp->state = 0; + } + } + INTON; +} +#endif + + +int +jobscmd(int argc __unused, char *argv[] __unused) +{ + char *id; + int ch, mode; + + mode = SHOWJOBS_DEFAULT; + while ((ch = nextopt("lps")) != '\0') { + switch (ch) { + case 'l': + mode = SHOWJOBS_VERBOSE; + break; + case 'p': + mode = SHOWJOBS_PGIDS; + break; + case 's': + mode = SHOWJOBS_PIDS; + break; + } + } + + if (*argptr == NULL) + showjobs(0, mode); + else + while ((id = *argptr++) != NULL) + showjob(getjob(id), mode); + + return (0); +} + +static int getjobstatus(const struct job *jp) +{ + int i, status; + + if (!jp->pipefail) + return (jp->ps[jp->nprocs - 1].status); + for (i = jp->nprocs - 1; i >= 0; i--) { + status = jp->ps[i].status; + if (status != 0) + return (status); + } + return (0); +} + +static void +printjobcmd(struct job *jp) +{ + struct procstat *ps; + int i; + + for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { + out1str(ps->cmd); + if (i > 0) + out1str(" | "); + } + out1c('\n'); +} + +static void +showjob(struct job *jp, int mode) +{ + char s[64]; + char statebuf[16]; + const char *statestr, *coredump; + struct procstat *ps; + struct job *j; + int col, curr, i, jobno, prev, procno, status; + char c; + + procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; + jobno = jp - jobtab + 1; + curr = prev = 0; +#if JOBS + if ((j = getcurjob(NULL)) != NULL) { + curr = j - jobtab + 1; + if ((j = getcurjob(j)) != NULL) + prev = j - jobtab + 1; + } +#endif + coredump = ""; + status = getjobstatus(jp); + if (jp->state == 0) { + statestr = "Running"; +#if JOBS + } else if (jp->state == JOBSTOPPED) { + ps = jp->ps + jp->nprocs - 1; + while (!WIFSTOPPED(ps->status) && ps > jp->ps) + ps--; + if (WIFSTOPPED(ps->status)) + i = WSTOPSIG(ps->status); + else + i = -1; + statestr = strsignal(i); + if (statestr == NULL) + statestr = "Suspended"; +#endif + } else if (WIFEXITED(status)) { + if (WEXITSTATUS(status) == 0) + statestr = "Done"; + else { + fmtstr(statebuf, sizeof(statebuf), "Done(%d)", + WEXITSTATUS(status)); + statestr = statebuf; + } + } else { + i = WTERMSIG(status); + statestr = strsignal(i); + if (statestr == NULL) + statestr = "Unknown signal"; + if (WCOREDUMP(status)) + coredump = " (core dumped)"; + } + + for (ps = jp->ps ; procno > 0 ; ps++, procno--) { /* for each process */ + if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { + out1fmt("%d\n", (int)ps->pid); + continue; + } + if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) + continue; + if (jobno == curr && ps == jp->ps) + c = '+'; + else if (jobno == prev && ps == jp->ps) + c = '-'; + else + c = ' '; + if (ps == jp->ps) + fmtstr(s, 64, "[%d] %c ", jobno, c); + else + fmtstr(s, 64, " %c ", c); + out1str(s); + col = strlen(s); + if (mode == SHOWJOBS_VERBOSE) { + fmtstr(s, 64, "%d ", (int)ps->pid); + out1str(s); + col += strlen(s); + } + if (ps == jp->ps) { + out1str(statestr); + out1str(coredump); + col += strlen(statestr) + strlen(coredump); + } + do { + out1c(' '); + col++; + } while (col < 30); + if (mode == SHOWJOBS_VERBOSE) { + out1str(ps->cmd); + out1c('\n'); + } else + printjobcmd(jp); + } +} + +/* + * Print a list of jobs. If "change" is nonzero, only print jobs whose + * statuses have changed since the last call to showjobs. + * + * If the shell is interrupted in the process of creating a job, the + * result may be a job structure containing zero processes. Such structures + * will be freed here. + */ + +void +showjobs(int change, int mode) +{ + int jobno; + struct job *jp; + + TRACE(("showjobs(%d) called\n", change)); + checkzombies(); + for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { + if (! jp->used) + continue; + if (jp->nprocs == 0) { + freejob(jp); + continue; + } + if (change && ! jp->changed) + continue; + showjob(jp, mode); + if (mode == SHOWJOBS_DEFAULT || mode == SHOWJOBS_VERBOSE) { + jp->changed = 0; + /* Hack: discard jobs for which $! has not been + * referenced in interactive mode when they terminate. + */ + if (jp->state == JOBDONE && !jp->remembered && + (iflag || jp != bgjob)) { + freejob(jp); + } + } + } +} + + +/* + * Mark a job structure as unused. + */ + +static void +freejob(struct job *jp) +{ + struct procstat *ps; + int i; + + INTOFF; + if (bgjob == jp) + bgjob = NULL; + for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { + if (ps->cmd != nullstr) + ckfree(ps->cmd); + } + if (jp->ps != &jp->ps0) + ckfree(jp->ps); + jp->used = 0; +#if JOBS + deljob(jp); +#endif + INTON; +} + + + +int +waitcmd(int argc __unused, char **argv __unused) +{ + struct job *job; + int retval; + + nextopt(""); + if (*argptr == NULL) + return (waitcmdloop(NULL)); + + do { + job = getjob_nonotfound(*argptr); + if (job == NULL) + retval = 127; + else + retval = waitcmdloop(job); + argptr++; + } while (*argptr != NULL); + + return (retval); +} + +static int +waitcmdloop(struct job *job) +{ + int status, retval, sig; + struct job *jp; + + /* + * Loop until a process is terminated or stopped, or a SIGINT is + * received. + */ + + do { + if (job != NULL) { + if (job->state == JOBDONE) { + status = getjobstatus(job); + if (WIFEXITED(status)) + retval = WEXITSTATUS(status); + else + retval = WTERMSIG(status) + 128; + if (! iflag || ! job->changed) + freejob(job); + else { + job->remembered = 0; + if (job == bgjob) + bgjob = NULL; + } + return retval; + } + } else { + if (njobs == 0) + return 0; + for (jp = jobtab ; jp < jobtab + njobs; jp++) + if (jp->used && jp->state == JOBDONE) { + if (! iflag || ! jp->changed) + freejob(jp); + else { + jp->remembered = 0; + if (jp == bgjob) + bgjob = NULL; + } + } + for (jp = jobtab ; ; jp++) { + if (jp >= jobtab + njobs) { /* no running procs */ + return 0; + } + if (jp->used && jp->state == 0) + break; + } + } + } while (dowait(DOWAIT_BLOCK | DOWAIT_SIG, (struct job *)NULL) != -1); + + sig = pendingsig_waitcmd; + pendingsig_waitcmd = 0; + return sig + 128; +} + + + +int +jobidcmd(int argc __unused, char **argv __unused) +{ + struct job *jp; + int i; + + nextopt(""); + jp = getjob(*argptr); + for (i = 0 ; i < jp->nprocs ; ) { + out1fmt("%d", (int)jp->ps[i].pid); + out1c(++i < jp->nprocs? ' ' : '\n'); + } + return 0; +} + + + +/* + * Convert a job name to a job structure. + */ + +static struct job * +getjob_nonotfound(const char *name) +{ + int jobno; + struct job *found, *jp; + size_t namelen; + pid_t pid; + int i; + + if (name == NULL) { +#if JOBS + name = "%+"; +#else + error("No current job"); +#endif + } + if (name[0] == '%') { + if (is_digit(name[1])) { + jobno = number(name + 1); + if (jobno > 0 && jobno <= njobs + && jobtab[jobno - 1].used != 0) + return &jobtab[jobno - 1]; +#if JOBS + } else if ((name[1] == '%' || name[1] == '+') && + name[2] == '\0') { + if ((jp = getcurjob(NULL)) == NULL) + error("No current job"); + return (jp); + } else if (name[1] == '-' && name[2] == '\0') { + if ((jp = getcurjob(NULL)) == NULL || + (jp = getcurjob(jp)) == NULL) + error("No previous job"); + return (jp); +#endif + } else if (name[1] == '?') { + found = NULL; + for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { + if (jp->used && jp->nprocs > 0 + && strstr(jp->ps[0].cmd, name + 2) != NULL) { + if (found) + error("%s: ambiguous", name); + found = jp; + } + } + if (found != NULL) + return (found); + } else { + namelen = strlen(name); + found = NULL; + for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { + if (jp->used && jp->nprocs > 0 + && strncmp(jp->ps[0].cmd, name + 1, + namelen - 1) == 0) { + if (found) + error("%s: ambiguous", name); + found = jp; + } + } + if (found) + return found; + } + } else if (is_number(name)) { + pid = (pid_t)number(name); + for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { + if (jp->used && jp->nprocs > 0 + && jp->ps[jp->nprocs - 1].pid == pid) + return jp; + } + } + return NULL; +} + + +static struct job * +getjob(const char *name) +{ + struct job *jp; + + jp = getjob_nonotfound(name); + if (jp == NULL) + error("No such job: %s", name); + return (jp); +} + + +int +killjob(const char *name, int sig) +{ + struct job *jp; + int i, ret; + + jp = getjob(name); + if (jp->state == JOBDONE) + return 0; + if (jp->jobctl) + return kill(-jp->ps[0].pid, sig); + ret = -1; + errno = ESRCH; + for (i = 0; i < jp->nprocs; i++) + if (jp->ps[i].status == -1 || WIFSTOPPED(jp->ps[i].status)) { + if (kill(jp->ps[i].pid, sig) == 0) + ret = 0; + } else + ret = 0; + return ret; +} + +/* + * Return a new job structure, + */ + +struct job * +makejob(union node *node __unused, int nprocs) +{ + int i; + struct job *jp; + + for (i = njobs, jp = jobtab ; ; jp++) { + if (--i < 0) { + INTOFF; + if (njobs == 0) { + jobtab = ckmalloc(4 * sizeof jobtab[0]); +#if JOBS + jobmru = NULL; +#endif + } else { + jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); + memcpy(jp, jobtab, njobs * sizeof jp[0]); +#if JOBS + /* Relocate `next' pointers and list head */ + if (jobmru != NULL) + jobmru = &jp[jobmru - jobtab]; + for (i = 0; i < njobs; i++) + if (jp[i].next != NULL) + jp[i].next = &jp[jp[i].next - + jobtab]; +#endif + if (bgjob != NULL) + bgjob = &jp[bgjob - jobtab]; + /* Relocate `ps' pointers */ + for (i = 0; i < njobs; i++) + if (jp[i].ps == &jobtab[i].ps0) + jp[i].ps = &jp[i].ps0; + ckfree(jobtab); + jobtab = jp; + } + jp = jobtab + njobs; + for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0) + ; + INTON; + break; + } + if (jp->used == 0) + break; + } + INTOFF; + jp->state = 0; + jp->used = 1; + jp->changed = 0; + jp->nprocs = 0; + jp->foreground = 0; + jp->remembered = 0; + jp->pipefail = pipefailflag; +#if JOBS + jp->jobctl = jobctl; + jp->next = NULL; +#endif + if (nprocs > 1) { + jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); + } else { + jp->ps = &jp->ps0; + } + INTON; + TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, + jp - jobtab + 1)); + return jp; +} + +#if JOBS +static void +setcurjob(struct job *cj) +{ + struct job *jp, *prev; + + for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { + if (jp == cj) { + if (prev != NULL) + prev->next = jp->next; + else + jobmru = jp->next; + jp->next = jobmru; + jobmru = cj; + return; + } + } + cj->next = jobmru; + jobmru = cj; +} + +static void +deljob(struct job *j) +{ + struct job *jp, *prev; + + for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { + if (jp == j) { + if (prev != NULL) + prev->next = jp->next; + else + jobmru = jp->next; + return; + } + } +} + +/* + * Return the most recently used job that isn't `nj', and preferably one + * that is stopped. + */ +static struct job * +getcurjob(struct job *nj) +{ + struct job *jp; + + /* Try to find a stopped one.. */ + for (jp = jobmru; jp != NULL; jp = jp->next) + if (jp->used && jp != nj && jp->state == JOBSTOPPED) + return (jp); + /* Otherwise the most recently used job that isn't `nj' */ + for (jp = jobmru; jp != NULL; jp = jp->next) + if (jp->used && jp != nj) + return (jp); + + return (NULL); +} + +#endif + +/* + * Fork of a subshell. If we are doing job control, give the subshell its + * own process group. Jp is a job structure that the job is to be added to. + * N is the command that will be evaluated by the child. Both jp and n may + * be NULL. The mode parameter can be one of the following: + * FORK_FG - Fork off a foreground process. + * FORK_BG - Fork off a background process. + * FORK_NOJOB - Like FORK_FG, but don't give the process its own + * process group even if job control is on. + * + * When job control is turned off, background processes have their standard + * input redirected to /dev/null (except for the second and later processes + * in a pipeline). + */ + +pid_t +forkshell(struct job *jp, union node *n, int mode) +{ + pid_t pid; + pid_t pgrp; + + TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, + mode)); + INTOFF; + if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) + checkzombies(); + flushall(); + pid = fork(); + if (pid == -1) { + TRACE(("Fork failed, errno=%d\n", errno)); + INTON; + error("Cannot fork: %s", strerror(errno)); + } + if (pid == 0) { + struct job *p; + int wasroot; + int i; + + TRACE(("Child shell %d\n", (int)getpid())); + wasroot = rootshell; + rootshell = 0; + handler = &main_handler; + closescript(); + INTON; + forcelocal = 0; + clear_traps(); +#if JOBS + jobctl = 0; /* do job control only in root shell */ + if (wasroot && mode != FORK_NOJOB && mflag) { + if (jp == NULL || jp->nprocs == 0) + pgrp = getpid(); + else + pgrp = jp->ps[0].pid; + if (setpgid(0, pgrp) == 0 && mode == FORK_FG && + ttyfd >= 0) { + /* + * Each process in a pipeline must have the tty + * pgrp set before running its code. + * Only for pipelines of three or more processes + * could this be reduced to two calls. + */ + if (tcsetpgrp(ttyfd, pgrp) < 0) + error("tcsetpgrp failed, errno=%d", errno); + } + setsignal(SIGTSTP); + setsignal(SIGTTOU); + } else if (mode == FORK_BG) { + ignoresig(SIGINT); + ignoresig(SIGQUIT); + if ((jp == NULL || jp->nprocs == 0) && + ! fd0_redirected_p ()) { + close(0); + if (open(_PATH_DEVNULL, O_RDONLY) != 0) + error("cannot open %s: %s", + _PATH_DEVNULL, strerror(errno)); + } + } +#else + if (mode == FORK_BG) { + ignoresig(SIGINT); + ignoresig(SIGQUIT); + if ((jp == NULL || jp->nprocs == 0) && + ! fd0_redirected_p ()) { + close(0); + if (open(_PATH_DEVNULL, O_RDONLY) != 0) + error("cannot open %s: %s", + _PATH_DEVNULL, strerror(errno)); + } + } +#endif + INTOFF; + for (i = njobs, p = jobtab ; --i >= 0 ; p++) + if (p->used) + freejob(p); + INTON; + if (wasroot && iflag) { + setsignal(SIGINT); + setsignal(SIGQUIT); + setsignal(SIGTERM); + } + return pid; + } + if (rootshell && mode != FORK_NOJOB && mflag) { + if (jp == NULL || jp->nprocs == 0) + pgrp = pid; + else + pgrp = jp->ps[0].pid; + setpgid(pid, pgrp); + } + if (mode == FORK_BG) { + if (bgjob != NULL && bgjob->state == JOBDONE && + !bgjob->remembered && !iflag) + freejob(bgjob); + backgndpid = pid; /* set $! */ + bgjob = jp; + } + if (jp) { + struct procstat *ps = &jp->ps[jp->nprocs++]; + ps->pid = pid; + ps->status = -1; + ps->cmd = nullstr; + if (iflag && rootshell && n) + ps->cmd = commandtext(n); + jp->foreground = mode == FORK_FG; +#if JOBS + setcurjob(jp); +#endif + } + INTON; + TRACE(("In parent shell: child = %d\n", (int)pid)); + return pid; +} + + +pid_t +vforkexecshell(struct job *jp, char **argv, char **envp, const char *path, int idx, int pip[2]) +{ + pid_t pid; + struct jmploc jmploc; + struct jmploc *savehandler; + int inton; + + TRACE(("vforkexecshell(%%%td, %s, %p) called\n", jp - jobtab, argv[0], + (void *)pip)); + inton = is_int_on(); + INTOFF; + flushall(); + savehandler = handler; + pid = vfork(); + if (pid == -1) { + TRACE(("Vfork failed, errno=%d\n", errno)); + INTON; + error("Cannot fork: %s", strerror(errno)); + } + if (pid == 0) { + TRACE(("Child shell %d\n", (int)getpid())); + if (setjmp(jmploc.loc)) + _exit(exitstatus); + if (pip != NULL) { + close(pip[0]); + if (pip[1] != 1) { + dup2(pip[1], 1); + close(pip[1]); + } + } + handler = &jmploc; + shellexec(argv, envp, path, idx); + } + handler = savehandler; + if (jp) { + struct procstat *ps = &jp->ps[jp->nprocs++]; + ps->pid = pid; + ps->status = -1; + ps->cmd = nullstr; + jp->foreground = 1; +#if JOBS + setcurjob(jp); +#endif + } + SETINTON(inton); + TRACE(("In parent shell: child = %d\n", (int)pid)); + return pid; +} + + +/* + * Wait for job to finish. + * + * Under job control we have the problem that while a child process is + * running interrupts generated by the user are sent to the child but not + * to the shell. This means that an infinite loop started by an inter- + * active user may be hard to kill. With job control turned off, an + * interactive user may place an interactive program inside a loop. If + * the interactive program catches interrupts, the user doesn't want + * these interrupts to also abort the loop. The approach we take here + * is to have the shell ignore interrupt signals while waiting for a + * foreground process to terminate, and then send itself an interrupt + * signal if the child process was terminated by an interrupt signal. + * Unfortunately, some programs want to do a bit of cleanup and then + * exit on interrupt; unless these processes terminate themselves by + * sending a signal to themselves (instead of calling exit) they will + * confuse this approach. + */ + +int +waitforjob(struct job *jp, int *signaled) +{ +#if JOBS + int propagate_int = jp->jobctl && jp->foreground; +#endif + int status; + int st; + + INTOFF; + TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); + while (jp->state == 0) + if (dowait(DOWAIT_BLOCK | (Tflag ? DOWAIT_SIG | + DOWAIT_SIG_TRAP : 0), jp) == -1) + dotrap(); +#if JOBS + if (jp->jobctl) { + if (ttyfd >= 0 && tcsetpgrp(ttyfd, rootpid) < 0) + error("tcsetpgrp failed, errno=%d\n", errno); + } + if (jp->state == JOBSTOPPED) + setcurjob(jp); +#endif + status = getjobstatus(jp); + if (signaled != NULL) + *signaled = WIFSIGNALED(status); + /* convert to 8 bits */ + if (WIFEXITED(status)) + st = WEXITSTATUS(status); +#if JOBS + else if (WIFSTOPPED(status)) + st = WSTOPSIG(status) + 128; +#endif + else + st = WTERMSIG(status) + 128; + if (! JOBS || jp->state == JOBDONE) + freejob(jp); + if (int_pending()) { + if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) + CLEAR_PENDING_INT; + } +#if JOBS + else if (rootshell && propagate_int && + WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) + kill(getpid(), SIGINT); +#endif + INTON; + return st; +} + + +static void +dummy_handler(int sig __unused) +{ +} + +/* + * Wait for a process to terminate. + */ + +static pid_t +dowait(int mode, struct job *job) +{ + struct sigaction sa, osa; + sigset_t mask, omask; + pid_t pid; + int status; + struct procstat *sp; + struct job *jp; + struct job *thisjob; + const char *sigstr; + int done; + int stopped; + int sig; + int coredump; + int wflags; + int restore_sigchld; + + TRACE(("dowait(%d, %p) called\n", mode, job)); + restore_sigchld = 0; + if ((mode & DOWAIT_SIG) != 0) { + sigfillset(&mask); + sigprocmask(SIG_BLOCK, &mask, &omask); + INTOFF; + if (!issigchldtrapped()) { + restore_sigchld = 1; + sa.sa_handler = dummy_handler; + sa.sa_flags = 0; + sigemptyset(&sa.sa_mask); + sigaction(SIGCHLD, &sa, &osa); + } + } + do { +#if JOBS + if (iflag) + wflags = WUNTRACED | WCONTINUED; + else +#endif + wflags = 0; + if ((mode & (DOWAIT_BLOCK | DOWAIT_SIG)) != DOWAIT_BLOCK) + wflags |= WNOHANG; + pid = wait3(&status, wflags, (struct rusage *)NULL); + TRACE(("wait returns %d, status=%d\n", (int)pid, status)); + if (pid == 0 && (mode & DOWAIT_SIG) != 0) { + pid = -1; + if (((mode & DOWAIT_SIG_TRAP) != 0 ? + pendingsig : pendingsig_waitcmd) != 0) { + errno = EINTR; + break; + } + sigsuspend(&omask); + if (int_pending()) + break; + } + } while (pid == -1 && errno == EINTR); + if (pid == -1 && errno == ECHILD && job != NULL) + job->state = JOBDONE; + if ((mode & DOWAIT_SIG) != 0) { + if (restore_sigchld) + sigaction(SIGCHLD, &osa, NULL); + sigprocmask(SIG_SETMASK, &omask, NULL); + INTON; + } + if (pid <= 0) + return pid; + INTOFF; + thisjob = NULL; + for (jp = jobtab ; jp < jobtab + njobs ; jp++) { + if (jp->used && jp->nprocs > 0) { + done = 1; + stopped = 1; + for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { + if (sp->pid == -1) + continue; + if (sp->pid == pid && (sp->status == -1 || + WIFSTOPPED(sp->status))) { + TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", + (int)pid, sp->status, + status)); + if (WIFCONTINUED(status)) { + sp->status = -1; + jp->state = 0; + } else + sp->status = status; + thisjob = jp; + } + if (sp->status == -1) + stopped = 0; + else if (WIFSTOPPED(sp->status)) + done = 0; + } + if (stopped) { /* stopped or done */ + int state = done? JOBDONE : JOBSTOPPED; + if (jp->state != state) { + TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); + jp->state = state; + if (jp != job) { + if (done && !jp->remembered && + !iflag && jp != bgjob) + freejob(jp); +#if JOBS + else if (done) + deljob(jp); +#endif + } + } + } + } + } + INTON; + if (!thisjob || thisjob->state == 0) + ; + else if ((!rootshell || !iflag || thisjob == job) && + thisjob->foreground && thisjob->state != JOBSTOPPED) { + sig = 0; + coredump = 0; + for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) + if (WIFSIGNALED(sp->status)) { + sig = WTERMSIG(sp->status); + coredump = WCOREDUMP(sp->status); + } + if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { + sigstr = strsignal(sig); + if (sigstr != NULL) + out2str(sigstr); + else + out2str("Unknown signal"); + if (coredump) + out2str(" (core dumped)"); + out2c('\n'); + flushout(out2); + } + } else { + TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); + thisjob->changed = 1; + } + return pid; +} + + + +/* + * return 1 if there are stopped jobs, otherwise 0 + */ +int job_warning = 0; +int +stoppedjobs(void) +{ + int jobno; + struct job *jp; + + if (job_warning) + return (0); + for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { + if (jp->used == 0) + continue; + if (jp->state == JOBSTOPPED) { + out2fmt_flush("You have stopped jobs.\n"); + job_warning = 2; + return (1); + } + } + + return (0); +} + + +static void +checkzombies(void) +{ + while (njobs > 0 && dowait(0, NULL) > 0) + ; +} + + +int +backgndpidset(void) +{ + return backgndpid != -1; +} + + +pid_t +backgndpidval(void) +{ + if (bgjob != NULL && !forcelocal) + bgjob->remembered = 1; + return backgndpid; +} + +/* + * Return a string identifying a command (to be printed by the + * jobs command. + */ + +static char *cmdnextc; +static int cmdnleft; +#define MAXCMDTEXT 200 + +char * +commandtext(union node *n) +{ + char *name; + + cmdnextc = name = ckmalloc(MAXCMDTEXT); + cmdnleft = MAXCMDTEXT - 4; + cmdtxt(n); + *cmdnextc = '\0'; + return name; +} + + +static void +cmdtxtdogroup(union node *n) +{ + cmdputs("; do "); + cmdtxt(n); + cmdputs("; done"); +} + + +static void +cmdtxtredir(union node *n, const char *op, int deffd) +{ + char s[2]; + + if (n->nfile.fd != deffd) { + s[0] = n->nfile.fd + '0'; + s[1] = '\0'; + cmdputs(s); + } + cmdputs(op); + if (n->type == NTOFD || n->type == NFROMFD) { + if (n->ndup.dupfd >= 0) + s[0] = n->ndup.dupfd + '0'; + else + s[0] = '-'; + s[1] = '\0'; + cmdputs(s); + } else { + cmdtxt(n->nfile.fname); + } +} + + +static void +cmdtxt(union node *n) +{ + union node *np; + struct nodelist *lp; + + if (n == NULL) + return; + switch (n->type) { + case NSEMI: + cmdtxt(n->nbinary.ch1); + cmdputs("; "); + cmdtxt(n->nbinary.ch2); + break; + case NAND: + cmdtxt(n->nbinary.ch1); + cmdputs(" && "); + cmdtxt(n->nbinary.ch2); + break; + case NOR: + cmdtxt(n->nbinary.ch1); + cmdputs(" || "); + cmdtxt(n->nbinary.ch2); + break; + case NPIPE: + for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { + cmdtxt(lp->n); + if (lp->next) + cmdputs(" | "); + } + break; + case NSUBSHELL: + cmdputs("("); + cmdtxt(n->nredir.n); + cmdputs(")"); + break; + case NREDIR: + case NBACKGND: + cmdtxt(n->nredir.n); + break; + case NIF: + cmdputs("if "); + cmdtxt(n->nif.test); + cmdputs("; then "); + cmdtxt(n->nif.ifpart); + cmdputs("..."); + break; + case NWHILE: + cmdputs("while "); + cmdtxt(n->nbinary.ch1); + cmdtxtdogroup(n->nbinary.ch2); + break; + case NUNTIL: + cmdputs("until "); + cmdtxt(n->nbinary.ch1); + cmdtxtdogroup(n->nbinary.ch2); + break; + case NFOR: + cmdputs("for "); + cmdputs(n->nfor.var); + cmdputs(" in ..."); + break; + case NCASE: + cmdputs("case "); + cmdputs(n->ncase.expr->narg.text); + cmdputs(" in ..."); + break; + case NDEFUN: + cmdputs(n->narg.text); + cmdputs("() ..."); + break; + case NNOT: + cmdputs("! "); + cmdtxt(n->nnot.com); + break; + case NCMD: + for (np = n->ncmd.args ; np ; np = np->narg.next) { + cmdtxt(np); + if (np->narg.next) + cmdputs(" "); + } + for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { + cmdputs(" "); + cmdtxt(np); + } + break; + case NARG: + cmdputs(n->narg.text); + break; + case NTO: + cmdtxtredir(n, ">", 1); + break; + case NAPPEND: + cmdtxtredir(n, ">>", 1); + break; + case NTOFD: + cmdtxtredir(n, ">&", 1); + break; + case NCLOBBER: + cmdtxtredir(n, ">|", 1); + break; + case NFROM: + cmdtxtredir(n, "<", 0); + break; + case NFROMTO: + cmdtxtredir(n, "<>", 0); + break; + case NFROMFD: + cmdtxtredir(n, "<&", 0); + break; + case NHERE: + case NXHERE: + cmdputs("<<..."); + break; + default: + cmdputs("???"); + break; + } +} + + + +static void +cmdputs(const char *s) +{ + const char *p; + char *q; + char c; + int subtype = 0; + + if (cmdnleft <= 0) + return; + p = s; + q = cmdnextc; + while ((c = *p++) != '\0') { + if (c == CTLESC) + *q++ = *p++; + else if (c == CTLVAR) { + *q++ = '$'; + if (--cmdnleft > 0) + *q++ = '{'; + subtype = *p++; + if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) + *q++ = '#'; + } else if (c == '=' && subtype != 0) { + *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; + if (*q) + q++; + else + cmdnleft++; + if (((subtype & VSTYPE) == VSTRIMLEFTMAX || + (subtype & VSTYPE) == VSTRIMRIGHTMAX) && + --cmdnleft > 0) + *q = q[-1], q++; + subtype = 0; + } else if (c == CTLENDVAR) { + *q++ = '}'; + } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { + cmdnleft -= 5; + if (cmdnleft > 0) { + *q++ = '$'; + *q++ = '('; + *q++ = '.'; + *q++ = '.'; + *q++ = '.'; + *q++ = ')'; + } + } else if (c == CTLARI) { + cmdnleft -= 2; + if (cmdnleft > 0) { + *q++ = '$'; + *q++ = '('; + *q++ = '('; + } + p++; + } else if (c == CTLENDARI) { + if (--cmdnleft > 0) { + *q++ = ')'; + *q++ = ')'; + } + } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) + cmdnleft++; /* ignore */ + else + *q++ = c; + if (--cmdnleft <= 0) { + *q++ = '.'; + *q++ = '.'; + *q++ = '.'; + break; + } + } + cmdnextc = q; +} |