* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.

/* $NetBSD: job.c,v 1.516 2025/06/13 06:13:19 rillig Exp $ */

/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Adam de Boor.
*
* 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.
*/

/*
* Copyright (c) 1988, 1989 by Adam de Boor
* Copyright (c) 1989 by Berkeley Softworks
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Adam de Boor.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/

/*
* Create child processes and collect their output.
*
* Interface:
* Job_Init Initialize this module and make the .BEGIN target.
*
* Job_End Clean up any memory used.
*
* Job_Make Start making the given target.
*
* Job_CatchChildren
* Handle the termination of any children.
*
* Job_CatchOutput
* Print any output the child processes have produced.
*
* Job_ParseShell Given a special dependency line with target '.SHELL',
* define the shell that is used for the creation
* commands in jobs mode.
*
* Job_Finish Make the .END target. Must only be called when the
* job table is empty.
*
* Job_AbortAll Kill all currently running jobs, in an emergency.
*
* Job_CheckCommands
* Add fallback commands to a target, if necessary.
*
* Job_Touch Update a target without really updating it.
*
* Job_Wait Wait for all currently-running jobs to finish.
*/

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/wait.h>

#include <errno.h>
#ifndef USE_SELECT
#include <poll.h>
#endif
#include <signal.h>
#include <utime.h>

#include "make.h"
#include "dir.h"
#include "job.h"
#ifdef USE_META
# include "meta.h"
#endif
#include "pathnames.h"
#include "trace.h"

/* "@(#)job.c 8.2 (Berkeley) 3/19/94" */
MAKE_RCSID("$NetBSD: job.c,v 1.516 2025/06/13 06:13:19 rillig Exp $");

#ifdef USE_SELECT
/*
* Emulate poll() in terms of select(). This is not a complete
* emulation but it is sufficient for make's purposes.
*/

#define poll emul_poll
#define pollfd emul_pollfd

struct emul_pollfd {
int fd;
short events;
short revents;
};

#define POLLIN 0x0001
#define POLLOUT 0x0004

int emul_poll(struct pollfd *, int, int);
#endif

struct pollfd;

enum JobStatus {
JOB_ST_FREE, /* Job is available */
JOB_ST_SET_UP, /* Job is allocated but otherwise invalid */
JOB_ST_RUNNING, /* Job is running, pid valid */
JOB_ST_FINISHED /* Job is done (i.e. after SIGCHLD) */
};

static const char JobStatus_Name[][9] = {
"free",
"set-up",
"running",
"finished",
};

/*
* A Job manages the shell commands that are run to create a single target.
* Each job is run in a separate subprocess by a shell. Several jobs can run
* in parallel.
*
* The shell commands for the target are written to a temporary file,
* then the shell is run with the temporary file as stdin, and the output
* of that shell is captured via a pipe.
*
* When a job is finished, Make_Update updates all parents of the node
* that was just remade, marking them as ready to be made next if all
* other dependencies are finished as well.
*/
struct Job {
/* The process ID of the shell running the commands */
int pid;

/* The target the child is making */
GNode *node;

/*
* If one of the shell commands is "...", all following commands are
* delayed until the .END node is made. This list node points to the
* first of these commands, if any.
*/
StringListNode *tailCmds;

/* This is where the shell commands go. */
FILE *cmdFILE;

int exit_status; /* from wait4() in signal handler */

enum JobStatus status;

bool suspended;

/* Ignore non-zero exits */
bool ignerr;
/* Output the command before or instead of running it. */
bool echo;
/* Target is a special one. */
bool special;

int inPipe; /* Pipe for reading output from job */
int outPipe; /* Pipe for writing control commands */
struct pollfd *inPollfd; /* pollfd associated with inPipe */

#define JOB_BUFSIZE 1024
/* Buffer for storing the output of the job, line by line. */
char outBuf[JOB_BUFSIZE + 1];
size_t outBufLen;

#ifdef USE_META
struct BuildMon bm;
#endif
};

/*
* A shell defines how the commands are run. All commands for a target are
* written into a single file, which is then given to the shell to execute
* the commands from it. The commands are written to the file using a few
* templates for echo control and error control.
*
* The name of the shell is the basename for the predefined shells, such as
* "sh", "csh", "bash". For custom shells, it is the full pathname, and its
* basename is used to select the type of shell; the longest match wins.
* So /usr/pkg/bin/bash has type sh, /usr/local/bin/tcsh has type csh.
*
* The echoing of command lines is controlled using hasEchoCtl, echoOff,
* echoOn, noPrint and noPrintLen. When echoOff is executed by the shell, it
* still outputs something, but this something is not interesting, therefore
* it is filtered out using noPrint and noPrintLen.
*
* The error checking for individual commands is controlled using hasErrCtl,
* errOn, errOff and runChkTmpl.
*
* In case a shell doesn't have error control, echoTmpl is a printf template
* for echoing the command, should echoing be on; runIgnTmpl is another
* printf template for executing the command while ignoring the return
* status. Finally runChkTmpl is a printf template for running the command and
* causing the shell to exit on error. If any of these strings are empty when
* hasErrCtl is false, the command will be executed anyway as is, and if it
* causes an error, so be it. Any templates set up to echo the command will
* escape any '$ ` \ "' characters in the command string to avoid unwanted
* shell code injection, the escaped command is safe to use in double quotes.
*
* The command-line flags "echo" and "exit" also control the behavior. The
* "echo" flag causes the shell to start echoing commands right away. The
* "exit" flag causes the shell to exit when an error is detected in one of
* the commands.
*/
typedef struct Shell {

/*
* The name of the shell. For Bourne and C shells, this is used only
* to find the shell description when used as the single source of a
* .SHELL target. For user-defined shells, this is the full path of
* the shell.
*/
const char *name;

bool hasEchoCtl; /* whether both echoOff and echoOn are there */
const char *echoOff; /* command to turn echoing off */
const char *echoOn; /* command to turn echoing back on */
const char *noPrint; /* text to skip when printing output from the
* shell. This is usually the same as echoOff */
size_t noPrintLen; /* length of noPrint command */

bool hasErrCtl; /* whether error checking can be controlled
* for individual commands */
const char *errOn; /* command to turn on error checking */
const char *errOff; /* command to turn off error checking */

const char *echoTmpl; /* template to echo a command */
const char *runIgnTmpl; /* template to run a command without error
* checking */
const char *runChkTmpl; /* template to run a command with error
* checking */

/*
* A string literal that results in a newline character when it
* occurs outside of any 'quote' or "quote" characters.
*/
const char *newline;
char commentChar; /* character used by shell for comment lines */

const char *echoFlag; /* shell flag to echo commands */
const char *errFlag; /* shell flag to exit on error */
} Shell;

typedef struct CommandFlags {
/* Whether to echo the command before or instead of running it. */
bool echo;

/* Run the command even in -n or -N mode. */
bool always;

/*
* true if we turned error checking off before writing the command to
* the commands file and need to turn it back on
*/
bool ignerr;
} CommandFlags;

/*
* Write shell commands to a file.
*
* TODO: keep track of whether commands are echoed.
* TODO: keep track of whether error checking is active.
*/
typedef struct ShellWriter {
FILE *f;

/* we've sent 'set -x' */
bool xtraced;

} ShellWriter;

/* error handling variables */
static int job_errors = 0; /* number of errors reported */
static enum { /* Why is the make aborting? */
ABORT_NONE,
ABORT_ERROR, /* Aborted because of an error */
ABORT_INTERRUPT, /* Aborted because it was interrupted */
ABORT_WAIT /* Waiting for jobs to finish */
} aborting = ABORT_NONE;
#define JOB_TOKENS "+EI+" /* Token to requeue for each abort state */

static const char aborting_name[][6] = { "NONE", "ERROR", "INTR", "WAIT" };

/* Tracks the number of tokens currently "out" to build jobs. */
int jobTokensRunning = 0;

/*
* Descriptions for various shells.
*
* The build environment may set DEFSHELL_INDEX to one of
* DEFSHELL_INDEX_SH, DEFSHELL_INDEX_KSH, or DEFSHELL_INDEX_CSH, to
* select one of the predefined shells as the default shell.
*
* Alternatively, the build environment may set DEFSHELL_CUSTOM to the
* name or the full path of a sh-compatible shell, which will be used as
* the default shell.
*
* ".SHELL" lines in Makefiles can choose the default shell from the
* set defined here, or add additional shells.
*/

#ifdef DEFSHELL_CUSTOM
#define DEFSHELL_INDEX_CUSTOM 0
#define DEFSHELL_INDEX_SH 1
#define DEFSHELL_INDEX_KSH 2
#define DEFSHELL_INDEX_CSH 3
#else
#define DEFSHELL_INDEX_SH 0
#define DEFSHELL_INDEX_KSH 1
#define DEFSHELL_INDEX_CSH 2
#endif

#ifndef DEFSHELL_INDEX
#define DEFSHELL_INDEX 0 /* DEFSHELL_INDEX_CUSTOM or DEFSHELL_INDEX_SH */
#endif

static Shell shells[] = {
#ifdef DEFSHELL_CUSTOM
/*
* An sh-compatible shell with a non-standard name.
*
* Keep this in sync with the "sh" description below, but avoid
* non-portable features that might not be supplied by all
* sh-compatible shells.
*/
{
DEFSHELL_CUSTOM, /* .name */
false, /* .hasEchoCtl */
"", /* .echoOff */
"", /* .echoOn */
"", /* .noPrint */
0, /* .noPrintLen */
false, /* .hasErrCtl */
"", /* .errOn */
"", /* .errOff */
"echo \"%s\"\n", /* .echoTmpl */
"%s\n", /* .runIgnTmpl */
"{ %s \n} || exit $?\n", /* .runChkTmpl */
"'\n'", /* .newline */
'#', /* .commentChar */
"", /* .echoFlag */
"", /* .errFlag */
},
#endif /* DEFSHELL_CUSTOM */
/*
* SH description. Echo control is also possible and, under
* sun UNIX anyway, one can even control error checking.
*/
{
"sh", /* .name */
false, /* .hasEchoCtl */
"", /* .echoOff */
"", /* .echoOn */
"", /* .noPrint */
0, /* .noPrintLen */
false, /* .hasErrCtl */
"", /* .errOn */
"", /* .errOff */
"echo \"%s\"\n", /* .echoTmpl */
"%s\n", /* .runIgnTmpl */
"{ %s \n} || exit $?\n", /* .runChkTmpl */
"'\n'", /* .newline */
'#', /* .commentChar*/
#if defined(MAKE_NATIVE) && defined(__NetBSD__)
/* XXX: -q is not really echoFlag, it's more like noEchoInSysFlag. */
"q", /* .echoFlag */
#else
"", /* .echoFlag */
#endif
"", /* .errFlag */
},
/*
* KSH description.
*/
{
"ksh", /* .name */
true, /* .hasEchoCtl */
"set +v", /* .echoOff */
"set -v", /* .echoOn */
"set +v", /* .noPrint */
6, /* .noPrintLen */
false, /* .hasErrCtl */
"", /* .errOn */
"", /* .errOff */
"echo \"%s\"\n", /* .echoTmpl */
"%s\n", /* .runIgnTmpl */
"{ %s \n} || exit $?\n", /* .runChkTmpl */
"'\n'", /* .newline */
'#', /* .commentChar */
"v", /* .echoFlag */
"", /* .errFlag */
},
/*
* CSH description. The csh can do echo control by playing
* with the setting of the 'echo' shell variable. Sadly,
* however, it is unable to do error control nicely.
*/
{
"csh", /* .name */
true, /* .hasEchoCtl */
"unset verbose", /* .echoOff */
"set verbose", /* .echoOn */
"unset verbose", /* .noPrint */
13, /* .noPrintLen */
false, /* .hasErrCtl */
"", /* .errOn */
"", /* .errOff */
"echo \"%s\"\n", /* .echoTmpl */
"csh -c \"%s || exit 0\"\n", /* .runIgnTmpl */
"", /* .runChkTmpl */
"'\\\n'", /* .newline */
'#', /* .commentChar */
"v", /* .echoFlag */
"e", /* .errFlag */
}
};

/*
* This is the shell to which we pass all commands in the Makefile.
* It is set by the Job_ParseShell function.
*/
static Shell *shell = &shells[DEFSHELL_INDEX];
char *shellPath; /* full pathname of executable image */
const char *shellName = NULL; /* last component of shellPath */
char *shellErrFlag = NULL;
static char *shell_freeIt = NULL; /* Allocated memory for custom .SHELL */

static Job *job_table; /* The structures that describe them */
static Job *job_table_end; /* job_table + maxJobs */
static bool wantToken;
static bool lurking_children = false;
static bool make_suspended = false; /* Whether we've seen a SIGTSTP (etc) */

/*
* Set of descriptors of pipes connected to
* the output channels of children
*/
static struct pollfd *fds = NULL;
static Job **jobByFdIndex = NULL;
static nfds_t fdsLen = 0;
static void watchfd(Job *);
static void clearfd(Job *);

static char *targPrefix = NULL; /* To identify a job change in the output. */

static Job tokenPoolJob; /* token wait pseudo-job */

static Job childExitJob; /* child exit pseudo-job */
#define CEJ_CHILD_EXITED '.'
#define CEJ_RESUME_JOBS 'R'

enum {
npseudojobs = 2 /* number of pseudo-jobs */
};

static sigset_t caught_signals; /* Set of signals we handle */
static volatile sig_atomic_t caught_sigchld;

static void CollectOutput(Job *, bool);
static void JobInterrupt(bool, int) MAKE_ATTR_DEAD;
static void JobSigReset(void);

static void
SwitchOutputTo(GNode *gn)
{
/* The node for which output was most recently produced. */
static GNode *lastNode = NULL;

if (gn == lastNode)
return;
lastNode = gn;

if (opts.maxJobs != 1 && targPrefix != NULL && targPrefix[0] != '\0')
(void)fprintf(stdout, "%s %s ---\n", targPrefix, gn->name);
}

static unsigned
nfds_per_job(void)
{
#if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
if (useMeta)
return 2;
#endif
return 1;
}

void
Job_FlagsToString(const Job *job, char *buf, size_t bufsize)
{
snprintf(buf, bufsize, "%c%c%c",
job->ignerr ? 'i' : '-',
!job->echo ? 's' : '-',
job->special ? 'S' : '-');
}

#ifdef USE_META
struct BuildMon *
Job_BuildMon(Job *job)
{
return &job->bm;
}
#endif

GNode *
Job_Node(Job *job)
{
return job->node;
}

int
Job_Pid(Job *job)
{
return job->pid;
}

static void
DumpJobs(const char *where)
{
const Job *job;
char flags[4];

debug_printf("%s, job table:\n", where);
for (job = job_table; job < job_table_end; job++) {
Job_FlagsToString(job, flags, sizeof flags);
debug_printf("job %d, status %s, flags %s, pid %d\n",
(int)(job - job_table), JobStatus_Name[job->status],
flags, job->pid);
}
}

/*
* Delete the target of a failed, interrupted, or otherwise
* unsuccessful job unless inhibited by .PRECIOUS.
*/
static void
JobDeleteTarget(GNode *gn)
{
const char *file;

if (gn->type & OP_JOIN)
return;
if (gn->type & OP_PHONY)
return;
if (GNode_IsPrecious(gn))
return;
if (opts.noExecute)
return;

file = GNode_Path(gn);
if (unlink_file(file) == 0)
Error("*** %s removed", file);
}

/* Lock the jobs table and the jobs therein. */
static void
JobsTable_Lock(sigset_t *omaskp)
{
if (sigprocmask(SIG_BLOCK, &caught_signals, omaskp) != 0)
Punt("JobsTable_Lock: %s", strerror(errno));
}

/* Unlock the jobs table and the jobs therein. */
static void
JobsTable_Unlock(sigset_t *omaskp)
{
(void)sigprocmask(SIG_SETMASK, omaskp, NULL);
}

static void
SetNonblocking(int fd)
{
int flags = fcntl(fd, F_GETFL, 0);
if (flags == -1)
Punt("SetNonblocking.get: %s", strerror(errno));
flags |= O_NONBLOCK;
if (fcntl(fd, F_SETFL, flags) == -1)
Punt("SetNonblocking.set: %s", strerror(errno));
}

static void
JobCreatePipe(Job *job, int minfd)
{
int i;
int pipe_fds[2];

if (pipe(pipe_fds) == -1)
Punt("JobCreatePipe: %s", strerror(errno));

for (i = 0; i < 2; i++) {
/* Avoid using low-numbered fds */
int fd = fcntl(pipe_fds[i], F_DUPFD, minfd);
if (fd != -1) {
close(pipe_fds[i]);
pipe_fds[i] = fd;
}
}

job->inPipe = pipe_fds[0];
job->outPipe = pipe_fds[1];

if (fcntl(job->inPipe, F_SETFD, FD_CLOEXEC) == -1)
Punt("SetCloseOnExec: %s", strerror(errno));
if (fcntl(job->outPipe, F_SETFD, FD_CLOEXEC) == -1)
Punt("SetCloseOnExec: %s", strerror(errno));

/*
* We mark the input side of the pipe non-blocking; we poll(2) the
* pipe when we're waiting for a job token, but we might lose the
* race for the token when a new one becomes available, so the read
* from the pipe should not block.
*/
SetNonblocking(job->inPipe);
}

/* Pass the signal to each running job. */
static void
JobCondPassSig(int signo)
{
Job *job;

DEBUG1(JOB, "JobCondPassSig: signal %d\n", signo);

for (job = job_table; job < job_table_end; job++) {
if (job->status != JOB_ST_RUNNING)
continue;
DEBUG2(JOB, "JobCondPassSig passing signal %d to pid %d\n",
signo, job->pid);
KILLPG(job->pid, signo);
}
}

static void
WriteOrDie(int fd, char ch)
{
if (write(fd, &ch, 1) != 1)
execDie("write", "child");
}

static void
HandleSIGCHLD(int signo MAKE_ATTR_UNUSED)
{
caught_sigchld = 1;
/* Wake up from poll(). */
WriteOrDie(childExitJob.outPipe, CEJ_CHILD_EXITED);
}

static void
HandleSIGCONT(int signo MAKE_ATTR_UNUSED)
{
WriteOrDie(childExitJob.outPipe, CEJ_RESUME_JOBS);
}

/*
* Pass a signal on to all jobs, then resend to ourselves.
* We die by the same signal.
*/
MAKE_ATTR_DEAD static void
JobPassSig_int(int signo)
{
/* Run .INTERRUPT target then exit */
JobInterrupt(true, signo);
}

/*
* Pass a signal on to all jobs, then resend to ourselves.
* We die by the same signal.
*/
MAKE_ATTR_DEAD static void
JobPassSig_term(int signo)
{
/* Dont run .INTERRUPT target then exit */
JobInterrupt(false, signo);
}

static void
JobPassSig_suspend(int signo)
{
sigset_t nmask, omask;
struct sigaction act;

/* Suppress job started/continued messages */
make_suspended = true;

/* Pass the signal onto every job */
JobCondPassSig(signo);

/*
* Send ourselves the signal now we've given the message to everyone
* else. Note we block everything else possible while we're getting
* the signal. This ensures that all our jobs get continued when we
* wake up before we take any other signal.
*/
sigfillset(&nmask);
sigdelset(&nmask, signo);
(void)sigprocmask(SIG_SETMASK, &nmask, &omask);

act.sa_handler = SIG_DFL;
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
(void)sigaction(signo, &act, NULL);

DEBUG1(JOB, "JobPassSig_suspend passing signal %d to self\n", signo);

(void)kill(getpid(), signo);

/*
* We've been continued.
*
* A whole host of signals is going to happen!
* SIGCHLD for any processes that actually suspended themselves.
* SIGCHLD for any processes that exited while we were asleep.
* The SIGCONT that actually caused us to wake up.
*
* Since we defer passing the SIGCONT on to our children until
* the main processing loop, we can be sure that all the SIGCHLD
* events will have happened by then - and that the waitpid() will
* collect the child 'suspended' events.
* For correct sequencing we just need to ensure we process the
* waitpid() before passing on the SIGCONT.
*
* In any case nothing else is needed here.
*/

/* Restore handler and signal mask */
act.sa_handler = JobPassSig_suspend;
(void)sigaction(signo, &act, NULL);
(void)sigprocmask(SIG_SETMASK, &omask, NULL);
}

static Job *
JobFindPid(int pid, enum JobStatus status, bool isJobs)
{
Job *job;

for (job = job_table; job < job_table_end; job++) {
if (job->status == status && job->pid == pid)
return job;
}
if (DEBUG(JOB) && isJobs)
DumpJobs("no pid");
return NULL;
}

/* Parse leading '@', '-' and '+', which control the exact execution mode. */
static void
ParseCommandFlags(char **pp, CommandFlags *out_cmdFlags)
{
char *p = *pp;
out_cmdFlags->echo = true;
out_cmdFlags->ignerr = false;
out_cmdFlags->always = false;

for (;;) {
if (*p == '@')
out_cmdFlags->echo = DEBUG(LOUD);
else if (*p == '-')
out_cmdFlags->ignerr = true;
else if (*p == '+')
out_cmdFlags->always = true;
else if (!ch_isspace(*p))
/* Ignore whitespace for compatibility with GNU make */
break;
p++;
}

*pp = p;
}

/* Escape a string for a double-quoted string literal in sh, csh and ksh. */
static char *
EscapeShellDblQuot(const char *cmd)
{
size_t i, j;

/* Worst that could happen is every char needs escaping. */
char *esc = bmake_malloc(strlen(cmd) * 2 + 1);
for (i = 0, j = 0; cmd[i] != '\0'; i++, j++) {
if (cmd[i] == '$' || cmd[i] == '`' || cmd[i] == '\\' ||
cmd[i] == '"')
esc[j++] = '\\';
esc[j] = cmd[i];
}
esc[j] = '\0';

return esc;
}

static void
ShellWriter_WriteFmt(ShellWriter *wr, const char *fmt, const char *arg)
{
DEBUG1(JOB, fmt, arg);

(void)fprintf(wr->f, fmt, arg);
if (wr->f == stdout)
(void)fflush(wr->f);
}

static void
ShellWriter_WriteLine(ShellWriter *wr, const char *line)
{
ShellWriter_WriteFmt(wr, "%s\n", line);
}

static void
ShellWriter_EchoOff(ShellWriter *wr)
{
if (shell->hasEchoCtl)
ShellWriter_WriteLine(wr, shell->echoOff);
}

static void
ShellWriter_EchoCmd(ShellWriter *wr, const char *escCmd)
{
ShellWriter_WriteFmt(wr, shell->echoTmpl, escCmd);
}

static void
ShellWriter_EchoOn(ShellWriter *wr)
{
if (shell->hasEchoCtl)
ShellWriter_WriteLine(wr, shell->echoOn);
}

static void
ShellWriter_TraceOn(ShellWriter *wr)
{
if (!wr->xtraced) {
ShellWriter_WriteLine(wr, "set -x");
wr->xtraced = true;
}
}

static void
ShellWriter_ErrOff(ShellWriter *wr, bool echo)
{
if (echo)
ShellWriter_EchoOff(wr);
ShellWriter_WriteLine(wr, shell->errOff);
if (echo)
ShellWriter_EchoOn(wr);
}

static void
ShellWriter_ErrOn(ShellWriter *wr, bool echo)
{
if (echo)
ShellWriter_EchoOff(wr);
ShellWriter_WriteLine(wr, shell->errOn);
if (echo)
ShellWriter_EchoOn(wr);
}

/*
* The shell has no built-in error control, so emulate error control by
* enclosing each shell command in a template like "{ %s \n } || exit $?"
* (configurable per shell).
*/
static void
JobWriteSpecialsEchoCtl(Job *job, ShellWriter *wr, CommandFlags *inout_cmdFlags,
const char *escCmd, const char **inout_cmdTemplate)
{
/* XXX: Why is the whole job modified at this point? */
job->ignerr = true;

if (job->echo && inout_cmdFlags->echo) {
ShellWriter_EchoOff(wr);
ShellWriter_EchoCmd(wr, escCmd);

/*
* Leave echoing off so the user doesn't see the commands
* for toggling the error checking.
*/
inout_cmdFlags->echo = false;
}
*inout_cmdTemplate = shell->runIgnTmpl;

/*
* The template runIgnTmpl already takes care of ignoring errors,
* so pretend error checking is still on.
* XXX: What effects does this have, and why is it necessary?
*/
inout_cmdFlags->ignerr = false;
}

static void
JobWriteSpecials(Job *job, ShellWriter *wr, const char *escCmd, bool run,
CommandFlags *inout_cmdFlags, const char **inout_cmdTemplate)
{
if (!run)
inout_cmdFlags->ignerr = false;
else if (shell->hasErrCtl)
ShellWriter_ErrOff(wr, job->echo && inout_cmdFlags->echo);
else if (shell->runIgnTmpl != NULL && shell->runIgnTmpl[0] != '\0') {
JobWriteSpecialsEchoCtl(job, wr, inout_cmdFlags, escCmd,
inout_cmdTemplate);
} else
inout_cmdFlags->ignerr = false;
}

/*
* Write a shell command to the job's commands file, to be run later.
*
* If the command starts with '@' and neither the -s nor the -n flag was
* given to make, stick a shell-specific echoOff command in the script.
*
* If the command starts with '-' and the shell has no error control (none
* of the predefined shells has that), ignore errors for the rest of the job.
*
* XXX: Why ignore errors for the entire job? This is documented in the
* manual page, but without giving a rationale.
*
* If the command is just "...", attach all further commands of this job to
* the .END node instead, see Job_Finish.
*/
static void
JobWriteCommand(Job *job, ShellWriter *wr, StringListNode *ln, const char *ucmd)
{
bool run;

CommandFlags cmdFlags;
/* Template for writing a command to the shell file */
const char *cmdTemplate;
char *xcmd; /* The expanded command */
char *xcmdStart;
char *escCmd; /* xcmd escaped to be used in double quotes */

run = GNode_ShouldExecute(job->node);

xcmd = Var_SubstInTarget(ucmd, job->node);
/* TODO: handle errors */
xcmdStart = xcmd;

cmdTemplate = "%s\n";

ParseCommandFlags(&xcmd, &cmdFlags);

/* The '+' command flag overrides the -n or -N options. */
if (cmdFlags.always && !run) {
/*
* We're not actually executing anything...
* but this one needs to be - use compat mode just for it.
*/
(void)Compat_RunCommand(ucmd, job->node, ln);
free(xcmdStart);
return;
}

/*
* If the shell doesn't have error control, the alternate echoing
* will be done (to avoid showing additional error checking code)
* and this needs some characters escaped.
*/
escCmd = shell->hasErrCtl ? NULL : EscapeShellDblQuot(xcmd);

if (!cmdFlags.echo) {
if (job->echo && run && shell->hasEchoCtl)
ShellWriter_EchoOff(wr);
else if (shell->hasErrCtl)
cmdFlags.echo = true;
}

if (cmdFlags.ignerr) {
JobWriteSpecials(job, wr, escCmd, run, &cmdFlags, &cmdTemplate);
} else {

/*
* If errors are being checked and the shell doesn't have
* error control but does supply an runChkTmpl template, then
* set up commands to run through it.
*/

if (!shell->hasErrCtl && shell->runChkTmpl != NULL &&
shell->runChkTmpl[0] != '\0') {
if (job->echo && cmdFlags.echo) {
ShellWriter_EchoOff(wr);
ShellWriter_EchoCmd(wr, escCmd);
cmdFlags.echo = false;
}
/*
* If it's a comment line or blank, avoid the possible
* syntax error generated by "{\n} || exit $?".
*/
cmdTemplate = escCmd[0] == shell->commentChar ||
escCmd[0] == '\0'
? shell->runIgnTmpl
: shell->runChkTmpl;
cmdFlags.ignerr = false;
}
}

if (DEBUG(SHELL) && strcmp(shellName, "sh") == 0)
ShellWriter_TraceOn(wr);

ShellWriter_WriteFmt(wr, cmdTemplate, xcmd);
free(xcmdStart);
free(escCmd);

if (cmdFlags.ignerr)
ShellWriter_ErrOn(wr, cmdFlags.echo && job->echo);

if (!cmdFlags.echo)
ShellWriter_EchoOn(wr);
}

/*
* Write all commands to the shell file that is later executed.
*
* The special command "..." stops writing and saves the remaining commands
* to be executed later, when the target '.END' is made.
*
* Return whether at least one command was written to the shell file.
*/
static bool
JobWriteCommands(Job *job)
{
StringListNode *ln;
bool seen = false;
ShellWriter wr;

wr.f = job->cmdFILE;
wr.xtraced = false;

for (ln = job->node->commands.first; ln != NULL; ln = ln->next) {
const char *cmd = ln->datum;

if (strcmp(cmd, "...") == 0) {
job->node->type |= OP_SAVE_CMDS;
job->tailCmds = ln->next;
break;
}

JobWriteCommand(job, &wr, ln, ln->datum);
seen = true;
}

return seen;
}

/*
* Save the delayed commands (those after '...'), to be executed later in
* the '.END' node, when everything else is done.
*/
static void
JobSaveCommands(Job *job)
{
StringListNode *ln;

for (ln = job->tailCmds; ln != NULL; ln = ln->next) {
const char *cmd = ln->datum;
char *expanded_cmd;
/*
* XXX: This Var_Subst is only intended to expand the dynamic
* variables such as .TARGET, .IMPSRC. It is not intended to
* expand the other variables as well; see deptgt-end.mk.
*/
expanded_cmd = Var_SubstInTarget(cmd, job->node);
/* TODO: handle errors */
Lst_Append(&Targ_GetEndNode()->commands, expanded_cmd);
Parse_RegisterCommand(expanded_cmd);
}
}

/* Close both input and output pipes when a job is finished. */
static void
JobClosePipes(Job *job)
{
clearfd(job);
(void)close(job->outPipe);
job->outPipe = -1;

CollectOutput(job, true);
(void)close(job->inPipe);
job->inPipe = -1;
}

static void
DebugFailedJob(const Job *job)
{
const StringListNode *ln;

if (!DEBUG(ERROR))
return;

debug_printf("\n");
debug_printf("*** Failed target: %s\n", job->node->name);
debug_printf("*** In directory: %s\n", curdir);
debug_printf("*** Failed commands:\n");
for (ln = job->node->commands.first; ln != NULL; ln = ln->next) {
const char *cmd = ln->datum;
debug_printf("\t%s\n", cmd);

if (strchr(cmd, '$') != NULL) {
char *xcmd = Var_Subst(cmd, job->node, VARE_EVAL);
debug_printf("\t=> %s\n", xcmd);
free(xcmd);
}
}
}

static void
JobFinishDoneExitedError(Job *job, int *inout_status)
{
SwitchOutputTo(job->node);
#ifdef USE_META
if (useMeta) {
meta_job_error(job, job->node,
job->ignerr, WEXITSTATUS(*inout_status));
}
#endif
if (!shouldDieQuietly(job->node, -1)) {
DebugFailedJob(job);
(void)printf("*** [%s] Error code %d%s\n",
job->node->name, WEXITSTATUS(*inout_status),
job->ignerr ? " (ignored)" : "");
}

if (job->ignerr)
*inout_status = 0;
else {
if (deleteOnError)
JobDeleteTarget(job->node);
PrintOnError(job->node, "\n");
}
}

static void
JobFinishDoneExited(Job *job, int *inout_status)
{
DEBUG2(JOB, "Target %s, pid %d exited\n",
job->node->name, job->pid);

if (WEXITSTATUS(*inout_status) != 0)
JobFinishDoneExitedError(job, inout_status);
else if (DEBUG(JOB)) {
SwitchOutputTo(job->node);
(void)printf("Target %s, pid %d exited successfully\n",
job->node->name, job->pid);
}
}

static void
JobFinishDoneSignaled(Job *job, int status)
{
SwitchOutputTo(job->node);
DebugFailedJob(job);
(void)printf("*** [%s] Signal %d\n", job->node->name, WTERMSIG(status));
if (deleteOnError)
JobDeleteTarget(job->node);
}

static void
JobFinishDone(Job *job, int *inout_status)
{
if (WIFEXITED(*inout_status))
JobFinishDoneExited(job, inout_status);
else
JobFinishDoneSignaled(job, *inout_status);

(void)fflush(stdout);
}

/*
* Finish the job, add deferred commands to the .END node, mark the job as
* free, update parent nodes and start new jobs as available/necessary.
*/
static void
JobFinish(Job *job, int status)
{
bool done, return_job_token;

DEBUG3(JOB, "JobFinish: target %s, pid %d, status %#x\n",
job->node->name, job->pid, status);

if ((WIFEXITED(status) &&
((WEXITSTATUS(status) != 0 && !job->ignerr))) ||
WIFSIGNALED(status)) {
/* Finished because of an error. */

JobClosePipes(job);
if (job->cmdFILE != NULL && job->cmdFILE != stdout) {
if (fclose(job->cmdFILE) != 0)
Punt("Cannot write shell script for \"%s\": %s",
job->node->name, strerror(errno));
job->cmdFILE = NULL;
}
done = true;

} else if (WIFEXITED(status)) {
/*
* Deal with ignored errors in -B mode. We need to print a
* message telling of the ignored error as well as to run
* the next command.
*/
done = WEXITSTATUS(status) != 0;

JobClosePipes(job);

} else {
/* No need to close things down or anything. */
done = false;
}

if (done)
JobFinishDone(job, &status);

#ifdef USE_META
if (useMeta) {
int meta_status = meta_job_finish(job);
if (meta_status != 0 && status == 0)
status = meta_status;
}
#endif

return_job_token = false;

Trace_Log(JOBEND, job);
if (!job->special) {
if (status != 0 ||
(aborting == ABORT_ERROR) || aborting == ABORT_INTERRUPT)
return_job_token = true;
}

if (aborting != ABORT_ERROR && aborting != ABORT_INTERRUPT &&
status == 0) {
JobSaveCommands(job);
job->node->made = MADE;
if (!job->special)
return_job_token = true;
Make_Update(job->node);
job->status = JOB_ST_FREE;
} else if (status != 0) {
job_errors++;
job->status = JOB_ST_FREE;
}

if (job_errors > 0 && !opts.keepgoing && aborting != ABORT_INTERRUPT) {
/* Prevent more jobs from getting started. */
aborting = ABORT_ERROR;
}

if (return_job_token)
TokenPool_Return();

if (aborting == ABORT_ERROR && jobTokensRunning == 0) {
if (shouldDieQuietly(NULL, -1))
exit(2);
Fatal("%d error%s", job_errors, job_errors == 1 ? "" : "s");
}
}

static void
TouchRegular(GNode *gn)
{
const char *file = GNode_Path(gn);
struct utimbuf times;
int fd;
char c;

times.actime = now;
times.modtime = now;
if (utime(file, &times) >= 0)
return;

fd = open(file, O_RDWR | O_CREAT, 0666);
if (fd < 0) {
(void)fprintf(stderr, "*** couldn't touch %s: %s\n",
file, strerror(errno));
(void)fflush(stderr);
return; /* XXX: What about propagating the error? */
}

/*
* Last resort: update the file's time stamps in the traditional way.
* XXX: This doesn't work for empty files, which are sometimes used
* as marker files.
*/
if (read(fd, &c, 1) == 1) {
(void)lseek(fd, 0, SEEK_SET);
while (write(fd, &c, 1) == -1 && errno == EAGAIN)
continue;
}
(void)close(fd); /* XXX: What about propagating the error? */
}

/*
* Touch the given target. Called by Job_Make when the -t flag was given.
*
* The modification date of the file is changed.
* If the file did not exist, it is created.
*/
void
Job_Touch(GNode *gn, bool echo)
{
if (gn->type &
(OP_JOIN | OP_USE | OP_USEBEFORE | OP_EXEC | OP_OPTIONAL |
OP_SPECIAL | OP_PHONY)) {
/*
* These are "virtual" targets and should not really be
* created.
*/
return;
}

if (echo || !GNode_ShouldExecute(gn)) {
(void)fprintf(stdout, "touch %s\n", gn->name);
(void)fflush(stdout);
}

if (!GNode_ShouldExecute(gn))
return;

if (gn->type & OP_ARCHV)
Arch_Touch(gn);
else if (gn->type & OP_LIB)
Arch_TouchLib(gn);
else
TouchRegular(gn);
}

/*
* Make sure the given node has all the commands it needs.
*
* The node will have commands from the .DEFAULT rule added to it if it
* needs them.
*
* Input:
* gn The target whose commands need verifying
* abortProc Function to abort with message
*
* Results:
* true if the commands are ok.
*/
bool
Job_CheckCommands(GNode *gn, void (*abortProc)(const char *, ...))
{
if (GNode_IsTarget(gn))
return true;
if (!Lst_IsEmpty(&gn->commands))
return true;
if ((gn->type & OP_LIB) && !Lst_IsEmpty(&gn->children))
return true;

/*
* No commands. Look for .DEFAULT rule from which we might infer
* commands.
*/
if (defaultNode != NULL && !Lst_IsEmpty(&defaultNode->commands) &&
!(gn->type & OP_SPECIAL)) {
/*
* The traditional Make only looks for a .DEFAULT if the node
* was never the target of an operator, so that's what we do
* too.
*
* The .DEFAULT node acts like a transformation rule, in that
* gn also inherits any attributes or sources attached to
* .DEFAULT itself.
*/
Make_HandleUse(defaultNode, gn);
Var_Set(gn, IMPSRC, GNode_VarTarget(gn));
return true;
}

Dir_UpdateMTime(gn, false);
if (gn->mtime != 0 || (gn->type & OP_SPECIAL))
return true;

/*
* The node wasn't the target of an operator. We have no .DEFAULT
* rule to go on and the target doesn't already exist. There's
* nothing more we can do for this branch. If the -k flag wasn't
* given, we stop in our tracks, otherwise we just don't update
* this node's parents so they never get examined.
*/

if (gn->flags.fromDepend) {
if (!Job_RunTarget(".STALE", gn->fname))
fprintf(stdout,
"%s: %s:%u: ignoring stale %s for %s\n",
progname, gn->fname, gn->lineno, makeDependfile,
gn->name);
return true;
}

if (gn->type & OP_OPTIONAL) {
(void)fprintf(stdout, "%s: don't know how to make %s (%s)\n",
progname, gn->name, "ignored");
(void)fflush(stdout);
return true;
}

if (opts.keepgoing) {
(void)fprintf(stdout, "%s: don't know how to make %s (%s)\n",
progname, gn->name, "continuing");
(void)fflush(stdout);
return false;
}

abortProc("don't know how to make %s. Stop", gn->name);
return false;
}

/*
* Execute the shell for the given job.
*
* See Job_CatchOutput for handling the output of the shell.
*/
static void
JobExec(Job *job, char **argv)
{
int cpid; /* ID of new child */
sigset_t mask;

if (DEBUG(JOB)) {
int i;

debug_printf("Running %s\n", job->node->name);
debug_printf("\tCommand:");
for (i = 0; argv[i] != NULL; i++) {
debug_printf(" %s", argv[i]);
}
debug_printf("\n");
}

/*
* Some jobs produce no output, and it's disconcerting to have
* no feedback of their running (since they produce no output, the
* banner with their name in it never appears). This is an attempt to
* provide that feedback, even if nothing follows it.
*/
if (job->echo)
SwitchOutputTo(job->node);

/* No interruptions until this job is in the jobs table. */
JobsTable_Lock(&mask);

/* Pre-emptively mark job running, pid still zero though */
job->status = JOB_ST_RUNNING;

Var_ReexportVars(job->node);
Var_ExportStackTrace(job->node->name, NULL);

cpid = FORK_FUNCTION();
if (cpid == -1)
Punt("fork: %s", strerror(errno));

if (cpid == 0) {
/* Child */
sigset_t tmask;

#ifdef USE_META
if (useMeta)
meta_job_child(job);
#endif
/*
* Reset all signal handlers; this is necessary because we
* also need to unblock signals before we exec(2).
*/
JobSigReset();

sigemptyset(&tmask);
JobsTable_Unlock(&tmask);

if (dup2(fileno(job->cmdFILE), STDIN_FILENO) == -1)
execDie("dup2", "job->cmdFILE");
if (fcntl(STDIN_FILENO, F_SETFD, 0) == -1)
execDie("clear close-on-exec", "stdin");
if (lseek(STDIN_FILENO, 0, SEEK_SET) == -1)
execDie("lseek to 0", "stdin");

if (job->node->type & (OP_MAKE | OP_SUBMAKE)) {
/* Pass job token pipe to submakes. */
if (fcntl(tokenPoolJob.inPipe, F_SETFD, 0) == -1)
execDie("clear close-on-exec",
"tokenPoolJob.inPipe");
if (fcntl(tokenPoolJob.outPipe, F_SETFD, 0) == -1)
execDie("clear close-on-exec",
"tokenPoolJob.outPipe");
}

if (dup2(job->outPipe, STDOUT_FILENO) == -1)
execDie("dup2", "job->outPipe");

/*
* The output channels are marked close on exec. This bit
* was duplicated by dup2 (on some systems), so we have
* to clear it before routing the shell's error output to
* the same place as its standard output.
*/
if (fcntl(STDOUT_FILENO, F_SETFD, 0) == -1)
execDie("clear close-on-exec", "stdout");
if (dup2(STDOUT_FILENO, STDERR_FILENO) == -1)
execDie("dup2", "1, 2");

/*
* We want to switch the child into a different process
* family so we can kill it and all its descendants in
* one fell swoop, by killing its process family, but not
* commit suicide.
*/
#if defined(MAKE_NATIVE) || defined(HAVE_SETPGID)
# if defined(SYSV)
/* XXX: dsl - I'm sure this should be setpgrp()... */
(void)setsid();
# else
(void)setpgid(0, getpid());
# endif
#endif

(void)execv(shellPath, argv);
execDie("exec", shellPath);
}

/* Parent, continuing after the child exec */
job->pid = cpid;

Trace_Log(JOBSTART, job);

#ifdef USE_META
if (useMeta)
meta_job_parent(job, cpid);
#endif

job->outBufLen = 0;

watchfd(job);

if (job->cmdFILE != NULL && job->cmdFILE != stdout) {
if (fclose(job->cmdFILE) != 0)
Punt("Cannot write shell script for \"%s\": %s",
job->node->name, strerror(errno));
job->cmdFILE = NULL;
}

if (DEBUG(JOB)) {
debug_printf(
"JobExec: target %s, pid %d added to jobs table\n",
job->node->name, job->pid);
DumpJobs("job started");
}
JobsTable_Unlock(&mask);
}

static void
BuildArgv(Job *job, char **argv)
{
int argc;
static char args[10];

argv[0] = UNCONST(shellName);
argc = 1;

if ((shell->errFlag != NULL && shell->errFlag[0] != '-') ||
(shell->echoFlag != NULL && shell->echoFlag[0] != '-')) {
/*
* At least one of the flags doesn't have a minus before it,
* so merge them together. Have to do this because the Bourne
* shell thinks its second argument is a file to source.
* Grrrr. Note the ten-character limitation on the combined
* arguments.
*
* TODO: Research until when the above comments were
* practically relevant.
*/
(void)snprintf(args, sizeof args, "-%s%s",
!job->ignerr && shell->errFlag != NULL
? shell->errFlag : "",
job->echo && shell->echoFlag != NULL
? shell->echoFlag : "");
if (args[1] != '\0') {
argv[argc] = args;
argc++;
}
} else {
if (!job->ignerr && shell->errFlag != NULL) {
argv[argc] = UNCONST(shell->errFlag);
argc++;
}
if (job->echo && shell->echoFlag != NULL) {
argv[argc] = UNCONST(shell->echoFlag);
argc++;
}
}
argv[argc] = NULL;
}

static void
JobWriteShellCommands(Job *job, GNode *gn, bool *out_run)
{
char fname[MAXPATHLEN];
int fd;

fd = Job_TempFile(NULL, fname, sizeof fname);

job->cmdFILE = fdopen(fd, "w+");
if (job->cmdFILE == NULL)
Punt("Could not fdopen %s", fname);

(void)fcntl(fd, F_SETFD, FD_CLOEXEC);

#ifdef USE_META
if (useMeta) {
meta_job_start(job, gn);
if (gn->type & OP_SILENT) /* might have changed */
job->echo = false;
}
#endif

*out_run = JobWriteCommands(job);
}

void
Job_Make(GNode *gn)
{
Job *job;
char *argv[10];
bool cmdsOK; /* true if the nodes commands were all right */
bool run;

for (job = job_table; job < job_table_end; job++) {
if (job->status == JOB_ST_FREE)
break;
}
if (job >= job_table_end)
Punt("Job_Make no job slots vacant");

memset(job, 0, sizeof *job);
job->node = gn;
job->tailCmds = NULL;
job->status = JOB_ST_SET_UP;

job->special = (gn->type & OP_SPECIAL) != OP_NONE;
job->ignerr = opts.ignoreErrors || gn->type & OP_IGNORE;
job->echo = !(opts.silent || gn->type & OP_SILENT);

/*
* Check the commands now so any attributes from .DEFAULT have a
* chance to migrate to the node.
*/
cmdsOK = Job_CheckCommands(gn, Error);

job->inPollfd = NULL;

if (Lst_IsEmpty(&gn->commands)) {
job->cmdFILE = stdout;
run = false;

if (!cmdsOK) {
PrintOnError(gn, "\n");
DieHorribly();
}
} else if (((gn->type & OP_MAKE) && !opts.noRecursiveExecute) ||
(!opts.noExecute && !opts.touch)) {
int parseErrorsBefore;

if (!cmdsOK) {
PrintOnError(gn, "\n");
DieHorribly();
}

parseErrorsBefore = parseErrors;
JobWriteShellCommands(job, gn, &run);
if (parseErrors != parseErrorsBefore)
run = false;
(void)fflush(job->cmdFILE);
} else if (!GNode_ShouldExecute(gn)) {
SwitchOutputTo(gn);
job->cmdFILE = stdout;
if (cmdsOK)
JobWriteCommands(job);
run = false;
(void)fflush(job->cmdFILE);
} else {
Job_Touch(gn, job->echo);
run = false;
}

if (!run) {
if (!job->special)
TokenPool_Return();

if (job->cmdFILE != NULL && job->cmdFILE != stdout) {
(void)fclose(job->cmdFILE);
job->cmdFILE = NULL;
}

if (cmdsOK && aborting == ABORT_NONE) {
JobSaveCommands(job);
job->node->made = MADE;
Make_Update(job->node);
}
job->status = JOB_ST_FREE;
return;
}

BuildArgv(job, argv);
JobCreatePipe(job, 3);
JobExec(job, argv);
}

/*
* If the shell has an output filter (which only csh and ksh have by default),
* print the output of the child process, skipping the noPrint text of the
* shell.
*
* Return the part of the output that the calling function needs to output by
* itself.
*/
static const char *
PrintFilteredOutput(Job *job, size_t len)
{
const char *p = job->outBuf, *ep, *endp;

if (shell->noPrint == NULL || shell->noPrint[0] == '\0')
return p;

endp = p + len;
while ((ep = strstr(p, shell->noPrint)) != NULL && ep < endp) {
if (ep > p) {
if (!opts.silent)
SwitchOutputTo(job->node);
(void)fwrite(p, 1, (size_t)(ep - p), stdout);
(void)fflush(stdout);
}
p = ep + shell->noPrintLen;
if (p == endp)
break;
p++; /* skip over the (XXX: assumed) newline */
cpp_skip_whitespace(&p);
}
return p;
}

/*
* Collect output from the job. Print any complete lines.
*
* In the output of the shell, the 'noPrint' lines are removed. If the
* command is not alone on the line (the character after it is not \0 or
* \n), we do print whatever follows it.
*
* If finish is true, collect all remaining output for the job.
*/
static void
CollectOutput(Job *job, bool finish)
{
const char *p;
size_t nr; /* number of bytes read */
size_t i; /* auxiliary index into outBuf */
size_t max; /* limit for i (end of current data) */

again:
nr = (size_t)read(job->inPipe, job->outBuf + job->outBufLen,
JOB_BUFSIZE - job->outBufLen);
if (nr == (size_t)-1) {
if (errno == EAGAIN)
return;
if (DEBUG(JOB))
perror("CollectOutput(piperead)");
nr = 0;
}

if (nr == 0)
finish = false; /* stop looping */

if (nr == 0 && job->outBufLen > 0) {
job->outBuf[job->outBufLen] = '\n';
nr = 1;
}

max = job->outBufLen + nr;
job->outBuf[max] = '\0';

for (i = job->outBufLen; i < max; i++)
if (job->outBuf[i] == '\0')
job->outBuf[i] = ' ';

for (i = max; i > job->outBufLen; i--)
if (job->outBuf[i - 1] == '\n')
break;

if (i == job->outBufLen) {
job->outBufLen = max;
if (max < JOB_BUFSIZE)
goto unfinished_line;
i = max;
}

p = PrintFilteredOutput(job, i);
if (*p != '\0') {
if (!opts.silent)
SwitchOutputTo(job->node);
#ifdef USE_META
if (useMeta)
meta_job_output(job, p);
#endif
(void)fwrite(p, 1, (size_t)(job->outBuf + i - p), stdout);
(void)fflush(stdout);
}
memmove(job->outBuf, job->outBuf + i, max - i);
job->outBufLen = max - i;

unfinished_line:
if (finish)
goto again;
}

static void
JobRun(GNode *target)
{
/* Don't let these special jobs overlap with other unrelated jobs. */
Compat_Make(target, target);
if (GNode_IsError(target)) {
PrintOnError(target, "\n\nStop.\n");
exit(1);
}
}

void
Job_CatchChildren(void)
{
int pid;
int status;

if (jobTokensRunning == 0)
return;
if (caught_sigchld == 0)
return;
caught_sigchld = 0;

while ((pid = waitpid((pid_t)-1, &status, WNOHANG | WUNTRACED)) > 0) {
DEBUG2(JOB,
"Process with pid %d exited/stopped with status %#x.\n",
pid, status);
JobReapChild(pid, status, true);
}
}

/*
* It is possible that wait[pid]() was called from elsewhere,
* this lets us reap jobs regardless.
*/
void
JobReapChild(pid_t pid, int status, bool isJobs)
{
Job *job;

if (jobTokensRunning == 0)
return;

job = JobFindPid(pid, JOB_ST_RUNNING, isJobs);
if (job == NULL) {
if (isJobs && !lurking_children)
Error("Child with pid %d and status %#x not in table?",
pid, status);
return;
}

if (WIFSTOPPED(status)) {
DEBUG2(JOB, "Process for target %s, pid %d stopped\n",
job->node->name, job->pid);
if (!make_suspended) {
switch (WSTOPSIG(status)) {
case SIGTSTP:
(void)printf("*** [%s] Suspended\n",
job->node->name);
break;
case SIGSTOP:
(void)printf("*** [%s] Stopped\n",
job->node->name);
break;
default:
(void)printf("*** [%s] Stopped -- signal %d\n",
job->node->name, WSTOPSIG(status));
}
job->suspended = true;
}
(void)fflush(stdout);
return;
}

job->status = JOB_ST_FINISHED;
job->exit_status = status;
if (WIFEXITED(status))
job->node->exit_status = WEXITSTATUS(status);

JobFinish(job, status);
}

static void
Job_Continue(Job *job)
{
DEBUG1(JOB, "Continuing pid %d\n", job->pid);
if (job->suspended) {
(void)printf("*** [%s] Continued\n", job->node->name);
(void)fflush(stdout);
job->suspended = false;
}
if (KILLPG(job->pid, SIGCONT) != 0)
DEBUG1(JOB, "Failed to send SIGCONT to pid %d\n", job->pid);
}

static void
ContinueJobs(void)
{
Job *job;

for (job = job_table; job < job_table_end; job++) {
if (job->status == JOB_ST_RUNNING &&
(make_suspended || job->suspended))
Job_Continue(job);
else if (job->status == JOB_ST_FINISHED)
JobFinish(job, job->exit_status);
}
make_suspended = false;
}

void
Job_CatchOutput(void)
{
int nready;
Job *job;
unsigned i;

(void)fflush(stdout);

do {
/* Maybe skip the job token pipe. */
nfds_t skip = wantToken ? 0 : 1;
nready = poll(fds + skip, fdsLen - skip, -1);
} while (nready < 0 && errno == EINTR);

if (nready < 0)
Punt("poll: %s", strerror(errno));

if (nready > 0 && childExitJob.inPollfd->revents & POLLIN) {
char token;
ssize_t count = read(childExitJob.inPipe, &token, 1);
if (count != 1)
Punt("childExitJob.read: %s",
count == 0 ? "EOF" : strerror(errno));
if (token == CEJ_RESUME_JOBS)
ContinueJobs();
nready--;
}

Job_CatchChildren();
if (nready == 0)
return;

for (i = npseudojobs * nfds_per_job(); i < fdsLen; i++) {
if (fds[i].revents == 0)
continue;
job = jobByFdIndex[i];
if (job->status == JOB_ST_RUNNING)
CollectOutput(job, false);
#if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
/*
* With meta mode, we may have activity on the job's filemon
* descriptor too, which at the moment is any pollfd other
* than job->inPollfd.
*/
if (useMeta && job->inPollfd != &fds[i]) {
if (meta_job_event(job) <= 0)
fds[i].events = 0; /* never mind */
}
#endif
if (--nready == 0)
return;
}
}

static void
InitShellNameAndPath(void)
{
shellName = shell->name;

#ifdef DEFSHELL_CUSTOM
if (shellName[0] == '/') {
shellPath = bmake_strdup(shellName);
shellName = str_basename(shellPath);
return;
}
#endif

shellPath = str_concat3(_PATH_DEFSHELLDIR, "/", shellName);
}

void
Shell_Init(void)
{
if (shellPath == NULL)
InitShellNameAndPath();

Var_SetWithFlags(SCOPE_CMDLINE, ".SHELL", shellPath,
VAR_SET_INTERNAL|VAR_SET_READONLY);
if (shell->errFlag == NULL)
shell->errFlag = "";
if (shell->echoFlag == NULL)
shell->echoFlag = "";
if (shell->hasErrCtl && shell->errFlag[0] != '\0') {
if (shellErrFlag != NULL &&
strcmp(shell->errFlag, &shellErrFlag[1]) != 0) {
free(shellErrFlag);
shellErrFlag = NULL;
}
if (shellErrFlag == NULL)
shellErrFlag = str_concat2("-", shell->errFlag);
} else if (shellErrFlag != NULL) {
free(shellErrFlag);
shellErrFlag = NULL;
}
}

/* Return the shell string literal that results in a newline character. */
const char *
Shell_GetNewline(void)
{
return shell->newline;
}

void
Job_SetPrefix(void)
{
if (targPrefix != NULL)
free(targPrefix);
else if (!Var_Exists(SCOPE_GLOBAL, ".MAKE.JOB.PREFIX"))
Global_Set(".MAKE.JOB.PREFIX", "---");

targPrefix = Var_Subst("${.MAKE.JOB.PREFIX}",
SCOPE_GLOBAL, VARE_EVAL);
/* TODO: handle errors */
}

static void
AddSig(int sig, SignalProc handler)
{
if (bmake_signal(sig, SIG_IGN) != SIG_IGN) {
sigaddset(&caught_signals, sig);
(void)bmake_signal(sig, handler);
}
}

void
Job_Init(void)
{
Job_SetPrefix();

job_table = bmake_malloc((size_t)opts.maxJobs * sizeof *job_table);
memset(job_table, 0, (size_t)opts.maxJobs * sizeof *job_table);
job_table_end = job_table + opts.maxJobs;
wantToken = false;
caught_sigchld = 0;

aborting = ABORT_NONE;
job_errors = 0;

/*
* There is a non-zero chance that we already have children,
* e.g. after 'make -f- <<EOF'.
* Since their termination causes a 'Child (pid) not in table'
* message, Collect the status of any that are already dead, and
* suppress the error message if there are any undead ones.
*/
for (;;) {
int rval, status;
rval = waitpid((pid_t)-1, &status, WNOHANG);
if (rval > 0)
continue;
if (rval == 0)
lurking_children = true;
break;
}

Shell_Init();

JobCreatePipe(&childExitJob, 3);

{
size_t nfds = (npseudojobs + (size_t)opts.maxJobs) *
nfds_per_job();
fds = bmake_malloc(sizeof *fds * nfds);
jobByFdIndex = bmake_malloc(sizeof *jobByFdIndex * nfds);
}

/* These are permanent entries and take slots 0 and 1 */
watchfd(&tokenPoolJob);
watchfd(&childExitJob);

sigemptyset(&caught_signals);
(void)bmake_signal(SIGCHLD, HandleSIGCHLD);
sigaddset(&caught_signals, SIGCHLD);

/* Handle the signals specified by POSIX. */
AddSig(SIGINT, JobPassSig_int);
AddSig(SIGHUP, JobPassSig_term);
AddSig(SIGTERM, JobPassSig_term);
AddSig(SIGQUIT, JobPassSig_term);

/*
* These signals need to be passed to the jobs, as each job has its
* own process group and thus the terminal driver doesn't forward the
* signals itself.
*/
AddSig(SIGTSTP, JobPassSig_suspend);
AddSig(SIGTTOU, JobPassSig_suspend);
AddSig(SIGTTIN, JobPassSig_suspend);
AddSig(SIGWINCH, JobCondPassSig);
AddSig(SIGCONT, HandleSIGCONT);

(void)Job_RunTarget(".BEGIN", NULL);
/* Create the .END node, see Targ_GetEndNode in Compat_MakeAll. */
(void)Targ_GetEndNode();
}

static void
DelSig(int sig)
{
if (sigismember(&caught_signals, sig) != 0)
(void)bmake_signal(sig, SIG_DFL);
}

static void
JobSigReset(void)
{
DelSig(SIGINT);
DelSig(SIGHUP);
DelSig(SIGQUIT);
DelSig(SIGTERM);
DelSig(SIGTSTP);
DelSig(SIGTTOU);
DelSig(SIGTTIN);
DelSig(SIGWINCH);
DelSig(SIGCONT);
(void)bmake_signal(SIGCHLD, SIG_DFL);
}

static Shell *
FindShellByName(const char *name)
{
Shell *sh = shells;
const Shell *shellsEnd = sh + sizeof shells / sizeof shells[0];

for (sh = shells; sh < shellsEnd; sh++) {
if (strcmp(name, sh->name) == 0)
return sh;
}
return NULL;
}

/*
* Parse a shell specification and set up 'shell', shellPath and
* shellName appropriately.
*
* Input:
* line The shell spec
*
* Results:
* Returns false if the specification was incorrect.
* If successful, 'shell' is usable, shellPath is the full path of the
* shell described by 'shell', and shellName is the final component of
* shellPath.
*
* Notes:
* A shell specification has the form ".SHELL: keyword=value...". Double
* quotes can be used to enclose blanks in words. A backslash escapes
* anything (most notably a double-quote and a space) and
* provides the usual escape sequences from C. There should be no
* unnecessary spaces in the word. The keywords are:
* name Name of shell.
* path Location of shell.
* quiet Command to turn off echoing.
* echo Command to turn echoing on
* filter The output from the shell command that turns off
* echoing, to be filtered from the final output.
* echoFlag Flag to turn echoing on at the start.
* errFlag Flag to turn error checking on at the start.
* hasErrCtl True if the shell has error checking control.
* newline String literal to represent a newline character.
* check If hasErrCtl is true: The command to turn on error
* checking. If hasErrCtl is false: The template for a
* shell command that echoes a command for which error
* checking is off.
* ignore If hasErrCtl is true: The command to turn off error
* checking. If hasErrCtl is false: The template for a
* shell command that executes a command so as to ignore
* any errors it returns.
*/
bool
Job_ParseShell(char *line)
{
Words wordsList;
char **words;
char **argv;
size_t argc;
char *path;
Shell newShell;
bool fullSpec = false;
Shell *sh;

/* XXX: don't use line as an iterator variable */
pp_skip_whitespace(&line);

free(shell_freeIt);

memset(&newShell, 0, sizeof newShell);

wordsList = Str_Words(line, true);
words = wordsList.words;
argc = wordsList.len;
path = wordsList.freeIt;
if (words == NULL) {
Error("Unterminated quoted string [%s]", line);
return false;
}
shell_freeIt = path;

for (path = NULL, argv = words; argc != 0; argc--, argv++) {
char *arg = *argv;
if (strncmp(arg, "path=", 5) == 0) {
path = arg + 5;
} else if (strncmp(arg, "name=", 5) == 0) {
newShell.name = arg + 5;
} else {
if (strncmp(arg, "quiet=", 6) == 0) {
newShell.echoOff = arg + 6;
} else if (strncmp(arg, "echo=", 5) == 0) {
newShell.echoOn = arg + 5;
} else if (strncmp(arg, "filter=", 7) == 0) {
newShell.noPrint = arg + 7;
newShell.noPrintLen = strlen(newShell.noPrint);
} else if (strncmp(arg, "echoFlag=", 9) == 0) {
newShell.echoFlag = arg + 9;
} else if (strncmp(arg, "errFlag=", 8) == 0) {
newShell.errFlag = arg + 8;
} else if (strncmp(arg, "hasErrCtl=", 10) == 0) {
char c = arg[10];
newShell.hasErrCtl = c == 'Y' || c == 'y' ||
c == 'T' || c == 't';
} else if (strncmp(arg, "newline=", 8) == 0) {
newShell.newline = arg + 8;
} else if (strncmp(arg, "check=", 6) == 0) {
/*
* Before 2020-12-10, these two variables had
* been a single variable.
*/
newShell.errOn = arg + 6;
newShell.echoTmpl = arg + 6;
} else if (strncmp(arg, "ignore=", 7) == 0) {
/*
* Before 2020-12-10, these two variables had
* been a single variable.
*/
newShell.errOff = arg + 7;
newShell.runIgnTmpl = arg + 7;
} else if (strncmp(arg, "errout=", 7) == 0) {
newShell.runChkTmpl = arg + 7;
} else if (strncmp(arg, "comment=", 8) == 0) {
newShell.commentChar = arg[8];
} else {
Parse_Error(PARSE_FATAL,
"Unknown keyword \"%s\"", arg);
free(words);
return false;
}
fullSpec = true;
}
}

if (path == NULL) {
if (newShell.name == NULL) {
Parse_Error(PARSE_FATAL,
"Neither path nor name specified");
free(words);
return false;
} else {
if ((sh = FindShellByName(newShell.name)) == NULL) {
Parse_Error(PARSE_WARNING,
"%s: No matching shell", newShell.name);
free(words);
return false;
}
shell = sh;
shellName = newShell.name;
if (shellPath != NULL) {
free(shellPath);
shellPath = NULL;
Shell_Init();
}
}
} else {
free(shellPath);
shellPath = bmake_strdup(path);
shellName = newShell.name != NULL ? newShell.name
: str_basename(path);
if (!fullSpec) {
if ((sh = FindShellByName(shellName)) == NULL) {
Parse_Error(PARSE_WARNING,
"%s: No matching shell", shellName);
free(words);
return false;
}
shell = sh;
} else {
shell = bmake_malloc(sizeof *shell);
*shell = newShell;
}
/* This will take care of shellErrFlag. */
Shell_Init();
}

if (shell->echoOn != NULL && shell->echoOff != NULL)
shell->hasEchoCtl = true;

if (!shell->hasErrCtl) {
if (shell->echoTmpl == NULL)
shell->echoTmpl = "";
if (shell->runIgnTmpl == NULL)
shell->runIgnTmpl = "%s\n";
}

/*
* Do not free up the words themselves, since they may be in use
* by the shell specification.
*/
free(words);
return true;
}

/*
* After receiving an interrupt signal, terminate all child processes and if
* necessary make the .INTERRUPT target.
*/
static void
JobInterrupt(bool runINTERRUPT, int signo)
{
Job *job;
GNode *interrupt;
sigset_t mask;

aborting = ABORT_INTERRUPT;

JobsTable_Lock(&mask);

for (job = job_table; job < job_table_end; job++) {
if (job->status == JOB_ST_RUNNING && job->pid != 0) {
DEBUG2(JOB,
"JobInterrupt passing signal %d to child %d.\n",
signo, job->pid);
KILLPG(job->pid, signo);
}
}

for (job = job_table; job < job_table_end; job++) {
if (job->status == JOB_ST_RUNNING && job->pid != 0) {
int status;
(void)waitpid(job->pid, &status, 0);
JobDeleteTarget(job->node);
}
}

JobsTable_Unlock(&mask);

if (runINTERRUPT && !opts.touch) {
interrupt = Targ_FindNode(".INTERRUPT");
if (interrupt != NULL) {
opts.ignoreErrors = false;
JobRun(interrupt);
}
}
Trace_Log(MAKEINTR, NULL);
exit(signo); /* XXX: why signo? */
}

/* Make the .END target, returning the number of job-related errors. */
int
Job_Finish(void)
{
GNode *endNode = Targ_GetEndNode();
if (!Lst_IsEmpty(&endNode->commands) ||
!Lst_IsEmpty(&endNode->children)) {
if (job_errors != 0)
Error("Errors reported so .END ignored");
else
JobRun(endNode);
}
return job_errors;
}

#ifdef CLEANUP
void
Job_End(void)
{
free(shell_freeIt);
}
#endif

/* Waits for all running jobs to finish. */
void
Job_Wait(void)
{
aborting = ABORT_WAIT; /* Prevent other jobs from starting. */
while (jobTokensRunning != 0)
Job_CatchOutput();
aborting = ABORT_NONE;
}

/*
* Abort all currently running jobs without handling output or anything.
* This function is to be called only in the event of a major error.
* Most definitely NOT to be called from JobInterrupt.
*/
void
Job_AbortAll(void)
{
Job *job;
int status;

aborting = ABORT_ERROR;

if (jobTokensRunning != 0) {
for (job = job_table; job < job_table_end; job++) {
if (job->status != JOB_ST_RUNNING)
continue;
KILLPG(job->pid, SIGINT);
KILLPG(job->pid, SIGKILL);
}
}

while (waitpid((pid_t)-1, &status, WNOHANG) > 0)
continue;
}

static void
watchfd(Job *job)
{
if (job->inPollfd != NULL)
Punt("Watching watched job");

fds[fdsLen].fd = job->inPipe;
fds[fdsLen].events = POLLIN;
jobByFdIndex[fdsLen] = job;
job->inPollfd = &fds[fdsLen];
fdsLen++;
#if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
if (useMeta) {
fds[fdsLen].fd = meta_job_fd(job);
fds[fdsLen].events = fds[fdsLen].fd == -1 ? 0 : POLLIN;
jobByFdIndex[fdsLen] = job;
fdsLen++;
}
#endif
}

static void
clearfd(Job *job)
{
size_t i;
if (job->inPollfd == NULL)
Punt("Unwatching unwatched job");
i = (size_t)(job->inPollfd - fds);
fdsLen--;
#if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
if (useMeta) {
assert(nfds_per_job() == 2);
if (i % 2 != 0)
Punt("odd-numbered fd with meta");
fdsLen--;
}
#endif
/* Move last job in table into hole made by dead job. */
if (fdsLen != i) {
fds[i] = fds[fdsLen];
jobByFdIndex[i] = jobByFdIndex[fdsLen];
jobByFdIndex[i]->inPollfd = &fds[i];
#if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
if (useMeta) {
fds[i + 1] = fds[fdsLen + 1];
jobByFdIndex[i + 1] = jobByFdIndex[fdsLen + 1];
}
#endif
}
job->inPollfd = NULL;
}

int
Job_TempFile(const char *pattern, char *tfile, size_t tfile_sz)
{
int fd;
sigset_t mask;

JobsTable_Lock(&mask);
fd = mkTempFile(pattern, tfile, tfile_sz);
if (tfile != NULL && !DEBUG(SCRIPT))
unlink(tfile);
JobsTable_Unlock(&mask);

return fd;
}

static void
TokenPool_Write(char tok)
{
if (write(tokenPoolJob.outPipe, &tok, 1) != 1)
Punt("Cannot write \"%c\" to the token pool: %s",
tok, strerror(errno));
}

/*
* Put a token (back) into the job token pool.
* This allows a make process to start a build job.
*/
static void
TokenPool_Add(void)
{
char tok = JOB_TOKENS[aborting], tok1;

/* If we are depositing an error token, flush everything else. */
while (tok != '+' && read(tokenPoolJob.inPipe, &tok1, 1) == 1)
continue;

DEBUG3(JOB, "TokenPool_Add: pid %d, aborting %s, token %c\n",
getpid(), aborting_name[aborting], tok);
TokenPool_Write(tok);
}

static void
TokenPool_InitClient(int tokenPoolReader, int tokenPoolWriter)
{
tokenPoolJob.inPipe = tokenPoolReader;
tokenPoolJob.outPipe = tokenPoolWriter;
(void)fcntl(tokenPoolReader, F_SETFD, FD_CLOEXEC);
(void)fcntl(tokenPoolWriter, F_SETFD, FD_CLOEXEC);
}

/* Prepare the job token pipe in the root make process. */
static void
TokenPool_InitServer(int maxJobTokens)
{
int i;
char jobarg[64];

JobCreatePipe(&tokenPoolJob, 15);

snprintf(jobarg, sizeof jobarg, "%d,%d",
tokenPoolJob.inPipe, tokenPoolJob.outPipe);

Global_Append(MAKEFLAGS, "-J");
Global_Append(MAKEFLAGS, jobarg);

/*
* Preload the job pipe with one token per job, save the one
* "extra" token for the primary job.
*/
SetNonblocking(tokenPoolJob.outPipe);
for (i = 1; i < maxJobTokens; i++)
TokenPool_Add();
}

void
TokenPool_Init(int maxJobTokens, int tokenPoolReader, int tokenPoolWriter)
{
if (tokenPoolReader >= 0 && tokenPoolWriter >= 0)
TokenPool_InitClient(tokenPoolReader, tokenPoolWriter);
else
TokenPool_InitServer(maxJobTokens);
}

/* Return a taken token to the pool. */
void
TokenPool_Return(void)
{
jobTokensRunning--;
if (jobTokensRunning < 0)
Punt("token botch");
if (jobTokensRunning != 0 || JOB_TOKENS[aborting] != '+')
TokenPool_Add();
}

/*
* Attempt to take a token from the pool.
*
* If the pool is empty, set wantToken so that we wake up when a token is
* released.
*
* Returns true if a token was taken, and false if the pool is currently
* empty.
*/
bool
TokenPool_Take(void)
{
char tok, tok1;
ssize_t count;

wantToken = false;
DEBUG3(JOB, "TokenPool_Take: pid %d, aborting %s, running %d\n",
getpid(), aborting_name[aborting], jobTokensRunning);

if (aborting != ABORT_NONE || jobTokensRunning >= opts.maxJobs)
return false;

count = read(tokenPoolJob.inPipe, &tok, 1);
if (count == 0)
Fatal("eof on job pipe");
if (count < 0 && jobTokensRunning != 0) {
if (errno != EAGAIN)
Fatal("job pipe read: %s", strerror(errno));
DEBUG1(JOB, "TokenPool_Take: pid %d blocked for token\n",
getpid());
wantToken = true;
return false;
}

if (count == 1 && tok != '+') {
/* make being aborted - remove any other job tokens */
DEBUG2(JOB, "TokenPool_Take: pid %d aborted by token %c\n",
getpid(), tok);
while (read(tokenPoolJob.inPipe, &tok1, 1) == 1)
continue;
/* And put the stopper back */
TokenPool_Write(tok);
if (shouldDieQuietly(NULL, 1)) {
Job_Wait();
exit(6);
}
Fatal("A failure has been detected "
"in another branch of the parallel make");
}

if (count == 1 && jobTokensRunning == 0)
/* We didn't want the token really */
TokenPool_Write(tok);

jobTokensRunning++;
DEBUG1(JOB, "TokenPool_Take: pid %d took a token\n", getpid());
return true;
}

/* Make the named target if found, exit if the target fails. */
bool
Job_RunTarget(const char *target, const char *fname)
{
GNode *gn = Targ_FindNode(target);
if (gn == NULL)
return false;

if (fname != NULL)
Var_Set(gn, ALLSRC, fname);

JobRun(gn);
return true;
}

#ifdef USE_SELECT
int
emul_poll(struct pollfd *fd, int nfd, int timeout)
{
fd_set rfds, wfds;
int i, maxfd, nselect, npoll;
struct timeval tv, *tvp;
long usecs;

FD_ZERO(&rfds);
FD_ZERO(&wfds);

maxfd = -1;
for (i = 0; i < nfd; i++) {
fd[i].revents = 0;

if (fd[i].events & POLLIN)
FD_SET(fd[i].fd, &rfds);

if (fd[i].events & POLLOUT)
FD_SET(fd[i].fd, &wfds);

if (fd[i].fd > maxfd)
maxfd = fd[i].fd;
}

if (maxfd >= FD_SETSIZE) {
Punt("Ran out of fd_set slots; "
"recompile with a larger FD_SETSIZE.");
}

if (timeout < 0) {
tvp = NULL;
} else {
usecs = timeout * 1000;
tv.tv_sec = usecs / 1000000;
tv.tv_usec = usecs % 1000000;
tvp = &tv;
}

nselect = select(maxfd + 1, &rfds, &wfds, NULL, tvp);

if (nselect <= 0)
return nselect;

npoll = 0;
for (i = 0; i < nfd; i++) {
if (FD_ISSET(fd[i].fd, &rfds))
fd[i].revents |= POLLIN;

if (FD_ISSET(fd[i].fd, &wfds))
fd[i].revents |= POLLOUT;

if (fd[i].revents)
npoll++;
}

return npoll;
}
#endif /* USE_SELECT */