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Diffstat (limited to 'usr/dash/jobs.c')
| -rw-r--r-- | usr/dash/jobs.c | 1504 |
1 files changed, 1504 insertions, 0 deletions
diff --git a/usr/dash/jobs.c b/usr/dash/jobs.c new file mode 100644 index 0000000..f027cc1 --- /dev/null +++ b/usr/dash/jobs.c @@ -0,0 +1,1504 @@ +/*- + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * Copyright (c) 1997-2005 + * Herbert Xu <herbert@gondor.apana.org.au>. 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 <fcntl.h> +#include <signal.h> +#include <unistd.h> +#include <stdlib.h> +#ifdef HAVE_PATHS_H +#include <paths.h> +#endif +#include <sys/types.h> +#include <sys/param.h> +#ifdef BSD +#include <sys/wait.h> +#include <sys/time.h> +#include <sys/resource.h> +#endif +#include <sys/ioctl.h> + +#include "shell.h" +#if JOBS +#include <termios.h> +#undef CEOF /* syntax.h redefines this */ +#endif +#include "redir.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 "system.h" + +/* mode flags for set_curjob */ +#define CUR_DELETE 2 +#define CUR_RUNNING 1 +#define CUR_STOPPED 0 + +/* mode flags for dowait */ +#define DOWAIT_NORMAL 0 +#define DOWAIT_BLOCK 1 +#define DOWAIT_WAITCMD 2 + +/* array of jobs */ +static struct job *jobtab; +/* size of array */ +static unsigned njobs; +/* pid of last background process */ +pid_t backgndpid; + +#if JOBS +/* pgrp of shell on invocation */ +static int initialpgrp; +/* control terminal */ +static int ttyfd = -1; +#endif + +/* current job */ +static struct job *curjob; +/* number of presumed living untracked jobs */ +static int jobless; + +STATIC void set_curjob(struct job *, unsigned); +STATIC int jobno(const struct job *); +STATIC int sprint_status(char *, int, int); +STATIC void freejob(struct job *); +STATIC struct job *getjob(const char *, int); +STATIC struct job *growjobtab(void); +STATIC void forkchild(struct job *, union node *, int); +STATIC void forkparent(struct job *, union node *, int, pid_t); +STATIC int dowait(int, struct job *); +#ifdef SYSV +STATIC int onsigchild(void); +#endif +STATIC int waitproc(int, int *); +STATIC char *commandtext(union node *); +STATIC void cmdtxt(union node *); +STATIC void cmdlist(union node *, int); +STATIC void cmdputs(const char *); +STATIC void showpipe(struct job *, struct output *); +STATIC int getstatus(struct job *); + +#if JOBS +static int restartjob(struct job *, int); +static void xtcsetpgrp(int, pid_t); +#endif + +STATIC void +set_curjob(struct job *jp, unsigned mode) +{ + struct job *jp1; + struct job **jpp, **curp; + + /* first remove from list */ + jpp = curp = &curjob; + do { + jp1 = *jpp; + if (jp1 == jp) + break; + jpp = &jp1->prev_job; + } while (1); + *jpp = jp1->prev_job; + + /* Then re-insert in correct position */ + jpp = curp; + switch (mode) { + default: +#ifdef DEBUG + abort(); +#endif + case CUR_DELETE: + /* job being deleted */ + break; + case CUR_RUNNING: + /* newly created job or backgrounded job, + put after all stopped jobs. */ + do { + jp1 = *jpp; + if (!JOBS || !jp1 || jp1->state != JOBSTOPPED) + break; + jpp = &jp1->prev_job; + } while (1); + /* FALLTHROUGH */ +#if JOBS + case CUR_STOPPED: +#endif + /* newly stopped job - becomes curjob */ + jp->prev_job = *jpp; + *jpp = jp; + break; + } +} + +#if JOBS +/* + * Turn job control on and off. + * + * Note: This code assumes that the third arg to ioctl is a character + * pointer, which is true on Berkeley systems but not System V. Since + * System V doesn't have job control yet, this isn't a problem now. + * + * Called with interrupts off. + */ + +int jobctl; + +void +setjobctl(int on) +{ + int fd; + int pgrp; + + if (on == jobctl || rootshell == 0) + return; + if (on) { + int ofd; + ofd = fd = open(_PATH_TTY, O_RDWR); + if (fd < 0) { + fd += 3; + while (!isatty(fd)) + if (--fd < 0) + goto out; + } + fd = savefd(fd, ofd); + do { /* while we are in the background */ + if ((pgrp = tcgetpgrp(fd)) < 0) { +out: + sh_warnx("can't access tty; job control turned off"); + mflag = on = 0; + goto close; + } + if (pgrp == getpgrp()) + break; + killpg(0, SIGTTIN); + } while (1); + initialpgrp = pgrp; + + setsignal(SIGTSTP); + setsignal(SIGTTOU); + setsignal(SIGTTIN); + pgrp = rootpid; + setpgid(0, pgrp); + xtcsetpgrp(fd, pgrp); + } else { + /* turning job control off */ + fd = ttyfd; + pgrp = initialpgrp; + xtcsetpgrp(fd, pgrp); + setpgid(0, pgrp); + setsignal(SIGTSTP); + setsignal(SIGTTOU); + setsignal(SIGTTIN); +close: + close(fd); + fd = -1; + } + ttyfd = fd; + jobctl = on; +} +#endif + + +int +killcmd(argc, argv) + int argc; + char **argv; +{ + int signo = -1; + int list = 0; + int i; + pid_t pid; + struct job *jp; + + if (argc <= 1) { +usage: + sh_error( +"Usage: kill [-s sigspec | -signum | -sigspec] [pid | job]... or\n" +"kill -l [exitstatus]" + ); + } + + if (**++argv == '-') { + signo = decode_signal(*argv + 1, 1); + if (signo < 0) { + int c; + + while ((c = nextopt("ls:")) != '\0') + switch (c) { + default: +#ifdef DEBUG + abort(); +#endif + case 'l': + list = 1; + break; + case 's': + signo = decode_signal(optionarg, 1); + if (signo < 0) { + sh_error( + "invalid signal number or name: %s", + optionarg + ); + } + break; + } + argv = argptr; + } else + argv++; + } + + if (!list && signo < 0) + signo = SIGTERM; + + if ((signo < 0 || !*argv) ^ list) { + goto usage; + } + + if (list) { + struct output *out; + + out = out1; + if (!*argv) { + outstr("0\n", out); + for (i = 1; i < NSIG; i++) { + outfmt(out, snlfmt, signal_name(i)); + } + return 0; + } + signo = number(*argv); + if (signo > 128) + signo -= 128; + if (0 < signo && signo < NSIG) + outfmt(out, snlfmt, signal_name(signo)); + else + sh_error("invalid signal number or exit status: %s", + *argv); + return 0; + } + + i = 0; + do { + if (**argv == '%') { + jp = getjob(*argv, 0); + pid = -jp->ps[0].pid; + } else + pid = **argv == '-' ? + -number(*argv + 1) : number(*argv); + if (kill(pid, signo) != 0) { + sh_warnx("%s\n", strerror(errno)); + i = 1; + } + } while (*++argv); + + return i; +} + +STATIC int +jobno(const struct job *jp) +{ + return jp - jobtab + 1; +} + +#if JOBS +int +fgcmd(int argc, char **argv) +{ + struct job *jp; + struct output *out; + int mode; + int retval; + + mode = (**argv == 'f') ? FORK_FG : FORK_BG; + nextopt(nullstr); + argv = argptr; + out = out1; + do { + jp = getjob(*argv, 1); + if (mode == FORK_BG) { + set_curjob(jp, CUR_RUNNING); + outfmt(out, "[%d] ", jobno(jp)); + } + outstr(jp->ps->cmd, out); + showpipe(jp, out); + retval = restartjob(jp, mode); + } while (*argv && *++argv); + return retval; +} + +int bgcmd(int argc, char **argv) +#ifdef HAVE_ALIAS_ATTRIBUTE + __attribute__((__alias__("fgcmd"))); +#else +{ + return fgcmd(argc, argv); +} +#endif + + +STATIC int +restartjob(struct job *jp, int mode) +{ + struct procstat *ps; + int i; + int status; + pid_t pgid; + + INTOFF; + if (jp->state == JOBDONE) + goto out; + jp->state = JOBRUNNING; + pgid = jp->ps->pid; + if (mode == FORK_FG) + xtcsetpgrp(ttyfd, pgid); + killpg(pgid, SIGCONT); + ps = jp->ps; + i = jp->nprocs; + do { + if (WIFSTOPPED(ps->status)) { + ps->status = -1; + } + } while (ps++, --i); +out: + status = (mode == FORK_FG) ? waitforjob(jp) : 0; + INTON; + return status; +} +#endif + +STATIC int +sprint_status(char *s, int status, int sigonly) +{ + int col; + int st; + + col = 0; + st = WEXITSTATUS(status); + if (!WIFEXITED(status)) { +#if JOBS + st = WSTOPSIG(status); + if (!WIFSTOPPED(status)) +#endif + st = WTERMSIG(status); + if (sigonly) { + if (st == SIGINT || st == SIGPIPE) + goto out; +#if JOBS + if (WIFSTOPPED(status)) + goto out; +#endif + } + col = fmtstr(s, 32, "%s", strsignal(st)); +#ifdef WCOREDUMP + if (WCOREDUMP(status)) { + col += fmtstr(s + col, 16, " (core dumped)"); + } +#endif + } else if (!sigonly) { + if (st) + col = fmtstr(s, 16, "Done(%d)", st); + else + col = fmtstr(s, 16, "Done"); + } + +out: + return col; +} + +static void +showjob(struct output *out, struct job *jp, int mode) +{ + struct procstat *ps; + struct procstat *psend; + int col; + int indent; + char s[80]; + + ps = jp->ps; + + if (mode & SHOW_PGID) { + /* just output process (group) id of pipeline */ + outfmt(out, "%d\n", ps->pid); + return; + } + + col = fmtstr(s, 16, "[%d] ", jobno(jp)); + indent = col; + + if (jp == curjob) + s[col - 2] = '+'; + else if (curjob && jp == curjob->prev_job) + s[col - 2] = '-'; + + if (mode & SHOW_PID) + col += fmtstr(s + col, 16, "%d ", ps->pid); + + psend = ps + jp->nprocs; + + if (jp->state == JOBRUNNING) { + scopy("Running", s + col); + col += strlen("Running"); + } else { + int status = psend[-1].status; +#if JOBS + if (jp->state == JOBSTOPPED) + status = jp->stopstatus; +#endif + col += sprint_status(s + col, status, 0); + } + + goto start; + + do { + /* for each process */ + col = fmtstr(s, 48, " |\n%*c%d ", indent, ' ', ps->pid) - 3; + +start: + outfmt( + out, "%s%*c%s", + s, 33 - col >= 0 ? 33 - col : 0, ' ', ps->cmd + ); + if (!(mode & SHOW_PID)) { + showpipe(jp, out); + break; + } + if (++ps == psend) { + outcslow('\n', out); + break; + } + } while (1); + + jp->changed = 0; + + if (jp->state == JOBDONE) { + TRACE(("showjob: freeing job %d\n", jobno(jp))); + freejob(jp); + } +} + + +int +jobscmd(int argc, char **argv) +{ + int mode, m; + struct output *out; + + mode = 0; + while ((m = nextopt("lp"))) + if (m == 'l') + mode = SHOW_PID; + else + mode = SHOW_PGID; + + out = out1; + argv = argptr; + if (*argv) + do + showjob(out, getjob(*argv,0), mode); + while (*++argv); + else + showjobs(out, mode); + + return 0; +} + + +/* + * Print a list of jobs. If "change" is nonzero, only print jobs whose + * statuses have changed since the last call to showjobs. + */ + +void +showjobs(struct output *out, int mode) +{ + struct job *jp; + + TRACE(("showjobs(%x) called\n", mode)); + + /* If not even one one job changed, there is nothing to do */ + while (dowait(DOWAIT_NORMAL, NULL) > 0) + continue; + + for (jp = curjob; jp; jp = jp->prev_job) { + if (!(mode & SHOW_CHANGED) || jp->changed) + showjob(out, jp, mode); + } +} + +/* + * Mark a job structure as unused. + */ + +STATIC void +freejob(struct job *jp) +{ + struct procstat *ps; + int i; + + INTOFF; + 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; + set_curjob(jp, CUR_DELETE); + INTON; +} + + + +int +waitcmd(int argc, char **argv) +{ + struct job *job; + int retval; + struct job *jp; + + nextopt(nullstr); + retval = 0; + + argv = argptr; + if (!*argv) { + /* wait for all jobs */ + for (;;) { + jp = curjob; + while (1) { + if (!jp) { + /* no running procs */ + goto out; + } + if (jp->state == JOBRUNNING) + break; + jp->waited = 1; + jp = jp->prev_job; + } + if (dowait(DOWAIT_WAITCMD, 0) <= 0) + goto sigout; + } + } + + retval = 127; + do { + if (**argv != '%') { + pid_t pid = number(*argv); + job = curjob; + goto start; + do { + if (job->ps[job->nprocs - 1].pid == pid) + break; + job = job->prev_job; +start: + if (!job) + goto repeat; + } while (1); + } else + job = getjob(*argv, 0); + /* loop until process terminated or stopped */ + while (job->state == JOBRUNNING) + if (dowait(DOWAIT_WAITCMD, 0) <= 0) + goto sigout; + job->waited = 1; + retval = getstatus(job); +repeat: + ; + } while (*++argv); + +out: + return retval; + +sigout: + retval = 128 + pendingsigs; + goto out; +} + + + +/* + * Convert a job name to a job structure. + */ + +STATIC struct job * +getjob(const char *name, int getctl) +{ + struct job *jp; + struct job *found; + const char *err_msg = "No such job: %s"; + unsigned num; + int c; + const char *p; + char *(*match)(const char *, const char *); + + jp = curjob; + p = name; + if (!p) + goto currentjob; + + if (*p != '%') + goto err; + + c = *++p; + if (!c) + goto currentjob; + + if (!p[1]) { + if (c == '+' || c == '%') { +currentjob: + err_msg = "No current job"; + goto check; + } else if (c == '-') { + if (jp) + jp = jp->prev_job; + err_msg = "No previous job"; +check: + if (!jp) + goto err; + goto gotit; + } + } + + if (is_number(p)) { + num = atoi(p); + if (num < njobs) { + jp = jobtab + num - 1; + if (jp->used) + goto gotit; + goto err; + } + } + + match = prefix; + if (*p == '?') { + match = strstr; + p++; + } + + found = 0; + while (1) { + if (!jp) + goto err; + if (match(jp->ps[0].cmd, p)) { + if (found) + goto err; + found = jp; + err_msg = "%s: ambiguous"; + } + jp = jp->prev_job; + } + +gotit: +#if JOBS + err_msg = "job %s not created under job control"; + if (getctl && jp->jobctl == 0) + goto err; +#endif + return jp; +err: + sh_error(err_msg, name); +} + + + +/* + * Return a new job structure. + * Called with interrupts off. + */ + +struct job * +makejob(union node *node, int nprocs) +{ + int i; + struct job *jp; + + for (i = njobs, jp = jobtab ; ; jp++) { + if (--i < 0) { + jp = growjobtab(); + break; + } + if (jp->used == 0) + break; + if (jp->state != JOBDONE || !jp->waited) + continue; + if (jobctl) + continue; + freejob(jp); + break; + } + memset(jp, 0, sizeof(*jp)); +#if JOBS + if (jobctl) + jp->jobctl = 1; +#endif + jp->prev_job = curjob; + curjob = jp; + jp->used = 1; + jp->ps = &jp->ps0; + if (nprocs > 1) { + jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); + } + TRACE(("makejob(0x%lx, %d) returns %%%d\n", (long)node, nprocs, + jobno(jp))); + return jp; +} + +STATIC struct job * +growjobtab(void) +{ + size_t len; + ptrdiff_t offset; + struct job *jp, *jq; + + len = njobs * sizeof(*jp); + jq = jobtab; + jp = ckrealloc(jq, len + 4 * sizeof(*jp)); + + offset = (char *)jp - (char *)jq; + if (offset) { + /* Relocate pointers */ + size_t l = len; + + jq = (struct job *)((char *)jq + l); + while (l) { + l -= sizeof(*jp); + jq--; +#define joff(p) ((struct job *)((char *)(p) + l)) +#define jmove(p) (p) = (void *)((char *)(p) + offset) + if (likely(joff(jp)->ps == &jq->ps0)) + jmove(joff(jp)->ps); + if (joff(jp)->prev_job) + jmove(joff(jp)->prev_job); + } + if (curjob) + jmove(curjob); +#undef joff +#undef jmove + } + + njobs += 4; + jobtab = jp; + jp = (struct job *)((char *)jp + len); + jq = jp + 3; + do { + jq->used = 0; + } while (--jq >= jp); + return jp; +} + + +/* + * Fork off 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). + * + * Called with interrupts off. + */ + +STATIC inline void +forkchild(struct job *jp, union node *n, int mode) +{ + int oldlvl; + + TRACE(("Child shell %d\n", getpid())); + oldlvl = shlvl; + shlvl++; + + closescript(); + clear_traps(); +#if JOBS + /* do job control only in root shell */ + jobctl = 0; + if (mode != FORK_NOJOB && jp->jobctl && !oldlvl) { + pid_t pgrp; + + if (jp->nprocs == 0) + pgrp = getpid(); + else + pgrp = jp->ps[0].pid; + /* This can fail because we are doing it in the parent also */ + (void)setpgid(0, pgrp); + if (mode == FORK_FG) + xtcsetpgrp(ttyfd, pgrp); + setsignal(SIGTSTP); + setsignal(SIGTTOU); + } else +#endif + if (mode == FORK_BG) { + ignoresig(SIGINT); + ignoresig(SIGQUIT); + if (jp->nprocs == 0) { + close(0); + if (open(_PATH_DEVNULL, O_RDONLY) != 0) + sh_error("Can't open %s", _PATH_DEVNULL); + } + } + if (!oldlvl && iflag) { + setsignal(SIGINT); + setsignal(SIGQUIT); + setsignal(SIGTERM); + } + for (jp = curjob; jp; jp = jp->prev_job) + freejob(jp); + jobless = 0; +} + +STATIC inline void +forkparent(struct job *jp, union node *n, int mode, pid_t pid) +{ + TRACE(("In parent shell: child = %d\n", pid)); + if (!jp) { + while (jobless && dowait(DOWAIT_NORMAL, 0) > 0); + jobless++; + return; + } +#if JOBS + if (mode != FORK_NOJOB && jp->jobctl) { + int pgrp; + + if (jp->nprocs == 0) + pgrp = pid; + else + pgrp = jp->ps[0].pid; + /* This can fail because we are doing it in the child also */ + (void)setpgid(pid, pgrp); + } +#endif + if (mode == FORK_BG) { + backgndpid = pid; /* set $! */ + set_curjob(jp, CUR_RUNNING); + } + if (jp) { + struct procstat *ps = &jp->ps[jp->nprocs++]; + ps->pid = pid; + ps->status = -1; + ps->cmd = nullstr; + if (jobctl && n) + ps->cmd = commandtext(n); + } +} + +int +forkshell(struct job *jp, union node *n, int mode) +{ + int pid; + + TRACE(("forkshell(%%%d, %p, %d) called\n", jobno(jp), n, mode)); + pid = fork(); + if (pid < 0) { + TRACE(("Fork failed, errno=%d", errno)); + if (jp) + freejob(jp); + sh_error("Cannot fork"); + } + if (pid == 0) + forkchild(jp, n, mode); + else + forkparent(jp, n, mode, 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 + * forground 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. + * + * Called with interrupts off. + */ + +int +waitforjob(struct job *jp) +{ + int st; + + TRACE(("waitforjob(%%%d) called\n", jobno(jp))); + while (jp->state == JOBRUNNING) { + dowait(DOWAIT_BLOCK, jp); + } + st = getstatus(jp); +#if JOBS + if (jp->jobctl) { + xtcsetpgrp(ttyfd, rootpid); + /* + * This is truly gross. + * If we're doing job control, then we did a TIOCSPGRP which + * caused us (the shell) to no longer be in the controlling + * session -- so we wouldn't have seen any ^C/SIGINT. So, we + * intuit from the subprocess exit status whether a SIGINT + * occurred, and if so interrupt ourselves. Yuck. - mycroft + */ + if (jp->sigint) + raise(SIGINT); + } +#endif + if (! JOBS || jp->state == JOBDONE) + freejob(jp); + return st; +} + + + +/* + * Wait for a process to terminate. + */ + +STATIC int +dowait(int block, struct job *job) +{ + int pid; + int status; + struct job *jp; + struct job *thisjob = NULL; + int state; + + INTOFF; + TRACE(("dowait(%d) called\n", block)); + pid = waitproc(block, &status); + TRACE(("wait returns pid %d, status=%d\n", pid, status)); + if (pid <= 0) + goto out; + + for (jp = curjob; jp; jp = jp->prev_job) { + struct procstat *sp; + struct procstat *spend; + if (jp->state == JOBDONE) + continue; + state = JOBDONE; + spend = jp->ps + jp->nprocs; + sp = jp->ps; + do { + if (sp->pid == pid) { + TRACE(("Job %d: changing status of proc %d from 0x%x to 0x%x\n", jobno(jp), pid, sp->status, status)); + sp->status = status; + thisjob = jp; + } + if (sp->status == -1) + state = JOBRUNNING; +#if JOBS + if (state == JOBRUNNING) + continue; + if (WIFSTOPPED(sp->status)) { + jp->stopstatus = sp->status; + state = JOBSTOPPED; + } +#endif + } while (++sp < spend); + if (thisjob) + goto gotjob; + } + if (!JOBS || !WIFSTOPPED(status)) + jobless--; + goto out; + +gotjob: + if (state != JOBRUNNING) { + thisjob->changed = 1; + + if (thisjob->state != state) { + TRACE(("Job %d: changing state from %d to %d\n", jobno(thisjob), thisjob->state, state)); + thisjob->state = state; +#if JOBS + if (state == JOBSTOPPED) { + set_curjob(thisjob, CUR_STOPPED); + } +#endif + } + } + +out: + INTON; + + if (thisjob && thisjob == job) { + char s[48 + 1]; + int len; + + len = sprint_status(s, status, 1); + if (len) { + s[len] = '\n'; + s[len + 1] = 0; + outstr(s, out2); + } + } + return pid; +} + + + +/* + * Do a wait system call. If job control is compiled in, we accept + * stopped processes. If block is zero, we return a value of zero + * rather than blocking. + * + * System V doesn't have a non-blocking wait system call. It does + * have a SIGCLD signal that is sent to a process when one of it's + * children dies. The obvious way to use SIGCLD would be to install + * a handler for SIGCLD which simply bumped a counter when a SIGCLD + * was received, and have waitproc bump another counter when it got + * the status of a process. Waitproc would then know that a wait + * system call would not block if the two counters were different. + * This approach doesn't work because if a process has children that + * have not been waited for, System V will send it a SIGCLD when it + * installs a signal handler for SIGCLD. What this means is that when + * a child exits, the shell will be sent SIGCLD signals continuously + * until is runs out of stack space, unless it does a wait call before + * restoring the signal handler. The code below takes advantage of + * this (mis)feature by installing a signal handler for SIGCLD and + * then checking to see whether it was called. If there are any + * children to be waited for, it will be. + * + * If neither SYSV nor BSD is defined, we don't implement nonblocking + * waits at all. In this case, the user will not be informed when + * a background process until the next time she runs a real program + * (as opposed to running a builtin command or just typing return), + * and the jobs command may give out of date information. + */ + +#ifdef SYSV +STATIC int gotsigchild; + +STATIC int onsigchild() { + gotsigchild = 1; +} +#endif + + +STATIC int +waitproc(int block, int *status) +{ + sigset_t mask, oldmask; + int flags = block == DOWAIT_BLOCK ? 0 : WNOHANG; + int err; + +#if JOBS + if (jobctl) + flags |= WUNTRACED; +#endif + + do { + gotsigchld = 0; + err = wait3(status, flags, NULL); + if (err || !block) + break; + + block = 0; + + sigfillset(&mask); + sigprocmask(SIG_SETMASK, &mask, &oldmask); + + while (!gotsigchld && !pendingsigs) + sigsuspend(&oldmask); + + sigclearmask(); + } while (gotsigchld); + + return err; +} + +/* + * return 1 if there are stopped jobs, otherwise 0 + */ +int job_warning; +int +stoppedjobs(void) +{ + struct job *jp; + int retval; + + retval = 0; + if (job_warning) + goto out; + jp = curjob; + if (jp && jp->state == JOBSTOPPED) { + out2str("You have stopped jobs.\n"); + job_warning = 2; + retval++; + } + +out: + return retval; +} + +/* + * Return a string identifying a command (to be printed by the + * jobs command). + */ + +STATIC char *cmdnextc; + +STATIC char * +commandtext(union node *n) +{ + char *name; + + STARTSTACKSTR(cmdnextc); + cmdtxt(n); + name = stackblock(); + TRACE(("commandtext: name %p, end %p\n", name, cmdnextc)); + return savestr(name); +} + + +STATIC void +cmdtxt(union node *n) +{ + union node *np; + struct nodelist *lp; + const char *p; + char s[2]; + + if (!n) + return; + switch (n->type) { + default: +#if DEBUG + abort(); +#endif + case NPIPE: + lp = n->npipe.cmdlist; + for (;;) { + cmdtxt(lp->n); + lp = lp->next; + if (!lp) + break; + cmdputs(" | "); + } + break; + case NSEMI: + p = "; "; + goto binop; + case NAND: + p = " && "; + goto binop; + case NOR: + p = " || "; +binop: + cmdtxt(n->nbinary.ch1); + cmdputs(p); + n = n->nbinary.ch2; + goto donode; + case NREDIR: + case NBACKGND: + n = n->nredir.n; + goto donode; + case NNOT: + cmdputs("!"); + n = n->nnot.com; +donode: + cmdtxt(n); + break; + case NIF: + cmdputs("if "); + cmdtxt(n->nif.test); + cmdputs("; then "); + if (n->nif.elsepart) { + cmdtxt(n->nif.ifpart); + cmdputs("; else "); + n = n->nif.elsepart; + } else { + n = n->nif.ifpart; + } + p = "; fi"; + goto dotail; + case NSUBSHELL: + cmdputs("("); + n = n->nredir.n; + p = ")"; + goto dotail; + case NWHILE: + p = "while "; + goto until; + case NUNTIL: + p = "until "; +until: + cmdputs(p); + cmdtxt(n->nbinary.ch1); + n = n->nbinary.ch2; + p = "; done"; +dodo: + cmdputs("; do "); +dotail: + cmdtxt(n); + goto dotail2; + case NFOR: + cmdputs("for "); + cmdputs(n->nfor.var); + cmdputs(" in "); + cmdlist(n->nfor.args, 1); + n = n->nfor.body; + p = "; done"; + goto dodo; + case NDEFUN: + cmdputs(n->ndefun.text); + p = "() { ... }"; + goto dotail2; + case NCMD: + cmdlist(n->ncmd.args, 1); + cmdlist(n->ncmd.redirect, 0); + break; + case NARG: + p = n->narg.text; +dotail2: + cmdputs(p); + break; + case NHERE: + case NXHERE: + p = "<<..."; + goto dotail2; + case NCASE: + cmdputs("case "); + cmdputs(n->ncase.expr->narg.text); + cmdputs(" in "); + for (np = n->ncase.cases; np; np = np->nclist.next) { + cmdtxt(np->nclist.pattern); + cmdputs(") "); + cmdtxt(np->nclist.body); + cmdputs(";; "); + } + p = "esac"; + goto dotail2; + case NTO: + p = ">"; + goto redir; + case NCLOBBER: + p = ">|"; + goto redir; + case NAPPEND: + p = ">>"; + goto redir; + case NTOFD: + p = ">&"; + goto redir; + case NFROM: + p = "<"; + goto redir; + case NFROMFD: + p = "<&"; + goto redir; + case NFROMTO: + p = "<>"; +redir: + s[0] = n->nfile.fd + '0'; + s[1] = '\0'; + cmdputs(s); + cmdputs(p); + if (n->type == NTOFD || n->type == NFROMFD) { + s[0] = n->ndup.dupfd + '0'; + p = s; + goto dotail2; + } else { + n = n->nfile.fname; + goto donode; + } + } +} + +STATIC void +cmdlist(union node *np, int sep) +{ + for (; np; np = np->narg.next) { + if (!sep) + cmdputs(spcstr); + cmdtxt(np); + if (sep && np->narg.next) + cmdputs(spcstr); + } +} + + +STATIC void +cmdputs(const char *s) +{ + const char *p, *str; + char cc[2] = " "; + char *nextc; + signed char c; + int subtype = 0; + int quoted = 0; + static const char vstype[VSTYPE + 1][4] = { + "", "}", "-", "+", "?", "=", + "%", "%%", "#", "##", + }; + + nextc = makestrspace((strlen(s) + 1) * 8, cmdnextc); + p = s; + while ((c = *p++) != 0) { + str = 0; + switch (c) { + case CTLESC: + c = *p++; + break; + case CTLVAR: + subtype = *p++; + if ((subtype & VSTYPE) == VSLENGTH) + str = "${#"; + else + str = "${"; + goto dostr; + case CTLENDVAR: + str = "\"}"; + str += !(quoted & 1); + quoted >>= 1; + subtype = 0; + goto dostr; + case CTLBACKQ: + str = "$(...)"; + goto dostr; + case CTLARI: + str = "$(("; + goto dostr; + case CTLENDARI: + str = "))"; + goto dostr; + case CTLQUOTEMARK: + quoted ^= 1; + c = '"'; + break; + case '=': + if (subtype == 0) + break; + if ((subtype & VSTYPE) != VSNORMAL) + quoted <<= 1; + str = vstype[subtype & VSTYPE]; + if (subtype & VSNUL) + c = ':'; + else + goto checkstr; + break; + case '\'': + case '\\': + case '"': + case '$': + /* These can only happen inside quotes */ + cc[0] = c; + str = cc; + c = '\\'; + break; + default: + break; + } + USTPUTC(c, nextc); +checkstr: + if (!str) + continue; +dostr: + while ((c = *str++)) { + USTPUTC(c, nextc); + } + } + if (quoted & 1) { + USTPUTC('"', nextc); + } + *nextc = 0; + cmdnextc = nextc; +} + + +STATIC void +showpipe(struct job *jp, struct output *out) +{ + struct procstat *sp; + struct procstat *spend; + + spend = jp->ps + jp->nprocs; + for (sp = jp->ps + 1; sp < spend; sp++) + outfmt(out, " | %s", sp->cmd); + outcslow('\n', out); + flushall(); +} + + +#if JOBS +STATIC void +xtcsetpgrp(int fd, pid_t pgrp) +{ + if (tcsetpgrp(fd, pgrp)) + sh_error("Cannot set tty process group (%s)", strerror(errno)); +} +#endif + + +STATIC int +getstatus(struct job *job) { + int status; + int retval; + + status = job->ps[job->nprocs - 1].status; + retval = WEXITSTATUS(status); + if (!WIFEXITED(status)) { +#if JOBS + retval = WSTOPSIG(status); + if (!WIFSTOPPED(status)) +#endif + { + /* XXX: limits number of signals */ + retval = WTERMSIG(status); +#if JOBS + if (retval == SIGINT) + job->sigint = 1; +#endif + } + retval += 128; + } + TRACE(("getstatus: job %d, nproc %d, status %x, retval %x\n", + jobno(job), job->nprocs, status, retval)); + return retval; +} |