#define EV_TESTED 02 /* exit status is checked; ignore -e flag */
#define EV_BACKCMD 04 /* command executing within back quotes */
-
static void evalloop(union node *, int);
static void evalfor(union node *, int);
static void evalcase(union node *, int);
static void prehash(union node *);
static int bltincmd(int, char **);
-
static const struct builtincmd bltin = {
"\0\0", bltincmd
};
-
/*
* Evaluate a parse tree. The value is left in the global variable
* exitstatus.
/* number of presumed living untracked jobs */
static int jobless;
-#if JOBS
-static char *commandtext(union node *);
-static void cmdlist(union node *, int);
-static void cmdtxt(union node *);
-static void cmdputs(const char *);
-#endif
-
static void
set_curjob(struct job *jp, unsigned mode)
{
col += sizeof("Running") - 1;
} else {
int status = psend[-1].status;
-#if JOBS
if (jp->state == JOBSTOPPED)
status = jp->stopstatus;
-#endif
col += sprint_status(s + col, status, 0);
}
return jp;
}
+#if JOBS
/*
- * 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.
+ * Return a string identifying a command (to be printed by the
+ * jobs command).
*/
+static char *cmdnextc;
+
static void
-forkchild(struct job *jp, union node *n, int mode)
+cmdputs(const char *s)
{
- 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;
+ const char *p, *str;
+ char c, cc[2] = " ";
+ char *nextc;
+ int subtype = 0;
+ int quoted = 0;
+ static const char vstype[VSTYPE + 1][4] = {
+ "", "}", "-", "+", "?", "=",
+ "%", "%%", "#", "##"
+ };
- 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
+ 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 = "${#";
+ else
+ str = "${";
+ if (!(subtype & VSQUOTE) == !(quoted & 1))
+ goto dostr;
+ quoted ^= 1;
+ c = '"';
+ break;
+ case CTLENDVAR:
+ str = "\"}" + !(quoted & 1);
+ quoted >>= 1;
+ subtype = 0;
+ goto dostr;
+ case CTLBACKQ:
+ str = "$(...)";
+ goto dostr;
+ case CTLBACKQ+CTLQUOTE:
+ str = "\"$(...)\"";
+ goto dostr;
+#if ENABLE_ASH_MATH_SUPPORT
+ case CTLARI:
+ str = "$((";
+ goto dostr;
+ case CTLENDARI:
+ str = "))";
+ goto dostr;
#endif
- if (mode == FORK_BG) {
- ignoresig(SIGINT);
- ignoresig(SIGQUIT);
- if (jp->nprocs == 0) {
- close(0);
- if (open(bb_dev_null, O_RDONLY) != 0)
- ash_msg_and_raise_error("Can't open %s", bb_dev_null);
+ case CTLQUOTEMARK:
+ quoted ^= 1;
+ c = '"';
+ break;
+ case '=':
+ if (subtype == 0)
+ break;
+ if ((subtype & VSTYPE) != VSNORMAL)
+ quoted <<= 1;
+ str = vstype[subtype & VSTYPE];
+ if (subtype & VSNUL)
+ c = ':';
+ else
+ goto checkstr;
+ break;
+ case '\'':
+ case '\\':
+ case '"':
+ case '$':
+ /* 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 (!oldlvl && iflag) {
- setsignal(SIGINT);
- setsignal(SIGQUIT);
- setsignal(SIGTERM);
+ if (quoted & 1) {
+ USTPUTC('"', nextc);
}
- for (jp = curjob; jp; jp = jp->prev_job)
- freejob(jp);
- jobless = 0;
+ *nextc = 0;
+ cmdnextc = nextc;
}
-static 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 */
- 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 JOBS
- if (jobctl && n)
- ps->cmd = commandtext(n);
-#endif
- }
-}
+/* cmdtxt() and cmdlist() call each other */
+static void cmdtxt(union node *n);
-static int
-forkshell(struct job *jp, union node *n, int mode)
+static void
+cmdlist(union node *np, int sep)
{
- 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);
- ash_msg_and_raise_error("Cannot fork");
+ for (; np; np = np->narg.next) {
+ if (!sep)
+ cmdputs(spcstr);
+ cmdtxt(np);
+ if (sep && np->narg.next)
+ cmdputs(spcstr);
}
- 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
- * 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.
- *
- * Called with interrupts off.
- */
-static int
-waitforjob(struct job *jp)
+static void
+cmdtxt(union node *n)
{
- 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);
- }
- if (jp->state == JOBDONE)
-#endif
- freejob(jp);
- return st;
-}
-
-/*
- * return 1 if there are stopped jobs, otherwise 0
- */
-static 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).
- */
-#if JOBS
-static char *cmdnextc;
-
-static char *
-commandtext(union node *n)
-{
- char *name;
-
- STARTSTACKSTR(cmdnextc);
- cmdtxt(n);
- name = stackblock();
- TRACE(("commandtext: name %p, end %p\n\t\"%s\"\n",
- name, cmdnextc, cmdnextc));
- return ckstrdup(name);
-}
-
-static void
-cmdtxt(union node *n)
-{
- union node *np;
- struct nodelist *lp;
- const char *p;
- char s[2];
+ union node *np;
+ struct nodelist *lp;
+ const char *p;
+ char s[2];
if (!n)
return;
}
}
+static char *
+commandtext(union node *n)
+{
+ char *name;
+
+ STARTSTACKSTR(cmdnextc);
+ cmdtxt(n);
+ name = stackblock();
+ TRACE(("commandtext: name %p, end %p\n\t\"%s\"\n",
+ name, cmdnextc, cmdnextc));
+ return ckstrdup(name);
+}
+#endif /* JOBS */
+
+/*
+ * 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 void
-cmdlist(union node *np, int sep)
+forkchild(struct job *jp, union node *n, int mode)
{
- for (; np; np = np->narg.next) {
- if (!sep)
- cmdputs(spcstr);
- cmdtxt(np);
- if (sep && np->narg.next)
- cmdputs(spcstr);
+ 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(bb_dev_null, O_RDONLY) != 0)
+ ash_msg_and_raise_error("Can't open %s", bb_dev_null);
+ }
}
+ if (!oldlvl && iflag) {
+ setsignal(SIGINT);
+ setsignal(SIGQUIT);
+ setsignal(SIGTERM);
+ }
+ for (jp = curjob; jp; jp = jp->prev_job)
+ freejob(jp);
+ jobless = 0;
}
static void
-cmdputs(const char *s)
+forkparent(struct job *jp, union node *n, int mode, pid_t pid)
{
- const char *p, *str;
- char c, cc[2] = " ";
- char *nextc;
- int subtype = 0;
- int quoted = 0;
- static const char vstype[VSTYPE + 1][4] = {
- "", "}", "-", "+", "?", "=",
- "%", "%%", "#", "##"
- };
+ 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;
- 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 = "${";
- if (!(subtype & VSQUOTE) == !(quoted & 1))
- goto dostr;
- quoted ^= 1;
- c = '"';
- break;
- case CTLENDVAR:
- str = "\"}" + !(quoted & 1);
- quoted >>= 1;
- subtype = 0;
- goto dostr;
- case CTLBACKQ:
- str = "$(...)";
- goto dostr;
- case CTLBACKQ+CTLQUOTE:
- str = "\"$(...)\"";
- goto dostr;
-#if ENABLE_ASH_MATH_SUPPORT
- case CTLARI:
- str = "$((";
- goto dostr;
- case CTLENDARI:
- str = "))";
- goto dostr;
+ if (jp->nprocs == 0)
+ pgrp = pid;
+ else
+ pgrp = jp->ps[0].pid;
+ /* This can fail because we are doing it in the child also */
+ setpgid(pid, pgrp);
+ }
#endif
- 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 (mode == FORK_BG) {
+ backgndpid = pid; /* set $! */
+ set_curjob(jp, CUR_RUNNING);
}
- if (quoted & 1) {
- USTPUTC('"', nextc);
+ if (jp) {
+ struct procstat *ps = &jp->ps[jp->nprocs++];
+ ps->pid = pid;
+ ps->status = -1;
+ ps->cmd = nullstr;
+#if JOBS
+ if (jobctl && n)
+ ps->cmd = commandtext(n);
+#endif
}
- *nextc = 0;
- cmdnextc = nextc;
}
-#endif /* JOBS */
+
+static 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);
+ ash_msg_and_raise_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
+ * 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.
+ *
+ * Called with interrupts off.
+ */
+static 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);
+ }
+ if (jp->state == JOBDONE)
+#endif
+ freejob(jp);
+ return st;
+}
+
+/*
+ * return 1 if there are stopped jobs, otherwise 0
+ */
+static 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;
+}
+
#if ENABLE_ASH_MAIL
/* mail.c */
/* trap.c */
-
-
/*
* The trap builtin.
*/
projects / oweals / busybox.git / commitdiff