main.c revision 146060 
1/*-
2 * Copyright (c) 1988, 1989, 1990, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 * Copyright (c) 1989 by Berkeley Softworks
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Adam de Boor.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the University of
21 *	California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)main.c      8.3 (Berkeley) 3/19/94
39 */
40
41#ifndef lint
42#if 0
43static char copyright[] =
44"@(#) Copyright (c) 1988, 1989, 1990, 1993\n\
45	The Regents of the University of California.  All rights reserved.\n";
46#endif
47#endif /* not lint */
48#include <sys/cdefs.h>
49__FBSDID("$FreeBSD: head/usr.bin/make/main.c 146060 2005-05-10 14:10:44Z harti $");
50
51/*
52 * main.c
53 *	The main file for this entire program. Exit routines etc
54 *	reside here.
55 *
56 * Utility functions defined in this file:
57 *	Main_ParseArgLine
58 *			Takes a line of arguments, breaks them and
59 *			treats them as if they were given when first
60 *			invoked. Used by the parse module to implement
61 *			the .MFLAGS target.
62 */
63
64#ifndef MACHINE
65#include <sys/utsname.h>
66#endif
67#include <sys/param.h>
68#include <sys/stat.h>
69#include <sys/sysctl.h>
70#include <sys/time.h>
71#include <sys/queue.h>
72#include <sys/resource.h>
73#include <sys/wait.h>
74#include <err.h>
75#include <errno.h>
76#include <signal.h>
77#include <stdlib.h>
78#include <string.h>
79#include <unistd.h>
80
81#include "arch.h"
82#include "buf.h"
83#include "config.h"
84#include "dir.h"
85#include "globals.h"
86#include "job.h"
87#include "make.h"
88#include "parse.h"
89#include "pathnames.h"
90#include "str.h"
91#include "suff.h"
92#include "targ.h"
93#include "util.h"
94#include "var.h"
95
96#define WANT_ENV_MKLVL	1
97#define	MKLVL_MAXVAL	500
98#define	MKLVL_ENVVAR	"__MKLVL__"
99
100#define	MAKEFLAGS	".MAKEFLAGS"
101
102extern char **environ;	/* XXX what header declares this variable? */
103
104/* Targets to be made */
105Lst create = Lst_Initializer(create);
106
107time_t		now;		/* Time at start of make */
108struct GNode	*DEFAULT;	/* .DEFAULT node */
109Boolean		allPrecious;	/* .PRECIOUS given on line by itself */
110uint32_t	warn_flags;	/* actual warning flags */
111uint32_t	warn_cmd;	/* command line warning flags */
112uint32_t	warn_nocmd;	/* command line no-warning flags */
113
114static Boolean	noBuiltins;	/* -r flag */
115
116/* ordered list of makefiles to read */
117static Lst makefiles = Lst_Initializer(makefiles);
118
119static Boolean	expandVars;	/* fully expand printed variables */
120
121/* list of variables to print */
122static Lst variables = Lst_Initializer(variables);
123
124int		maxJobs;	/* -j argument */
125static Boolean	forceJobs;      /* -j argument given */
126Boolean		compatMake;	/* -B argument */
127Boolean		debug;		/* -d flag */
128Boolean		noExecute;	/* -n flag */
129Boolean		keepgoing;	/* -k flag */
130Boolean		queryFlag;	/* -q flag */
131Boolean		touchFlag;	/* -t flag */
132Boolean		usePipes;	/* !-P flag */
133Boolean		ignoreErrors;	/* -i flag */
134Boolean		beSilent;	/* -s flag */
135Boolean		beVerbose;	/* -v flag */
136Boolean		oldVars;	/* variable substitution style */
137Boolean		checkEnvFirst;	/* -e flag */
138
139/* (-E) vars to override from env */
140Lst envFirstVars = Lst_Initializer(envFirstVars);
141
142Boolean		jobsRunning;	/* TRUE if the jobs might be running */
143
144char		*chdir_verify_path(const char *, char *);
145static int	ReadMakefile(const char *);
146static void	usage(void);
147
148static char	*curdir;	/* startup directory */
149static char	*objdir;	/* where we chdir'ed to */
150
151/**
152 * MFLAGS_append
153 *	Append a flag with an optional argument to MAKEFLAGS and MFLAGS
154 */
155static void
156MFLAGS_append(const char *flag, char *arg)
157{
158	char *str;
159
160	Var_Append(MAKEFLAGS, flag, VAR_GLOBAL);
161	if (arg != NULL) {
162		str = MAKEFLAGS_quote(arg);
163		Var_Append(MAKEFLAGS, str, VAR_GLOBAL);
164		free(str);
165	}
166
167	Var_Append("MFLAGS", flag, VAR_GLOBAL);
168	if (arg != NULL) {
169		str = MAKEFLAGS_quote(arg);
170		Var_Append("MFLAGS", str, VAR_GLOBAL);
171		free(str);
172	}
173}
174
175/**
176 * Main_ParseWarn
177 *
178 *	Handle argument to warning option.
179 */
180int
181Main_ParseWarn(const char *arg, int iscmd)
182{
183	int i, neg;
184
185	static const struct {
186		const char	*option;
187		uint32_t	flag;
188	} options[] = {
189		{ "dirsyntax",	WARN_DIRSYNTAX },
190		{ NULL,		0 }
191	};
192
193	neg = 0;
194	if (arg[0] == 'n' && arg[1] == 'o') {
195		neg = 1;
196		arg += 2;
197	}
198
199	for (i = 0; options[i].option != NULL; i++)
200		if (strcmp(arg, options[i].option) == 0)
201			break;
202
203	if (options[i].option == NULL)
204		/* unknown option */
205		return (-1);
206
207	if (iscmd) {
208		if (!neg) {
209			warn_cmd |= options[i].flag;
210			warn_nocmd &= ~options[i].flag;
211			warn_flags |= options[i].flag;
212		} else {
213			warn_nocmd |= options[i].flag;
214			warn_cmd &= ~options[i].flag;
215			warn_flags &= ~options[i].flag;
216		}
217	} else {
218		if (!neg) {
219			warn_flags |= (options[i].flag & ~warn_nocmd);
220		} else {
221			warn_flags &= ~(options[i].flag | warn_cmd);
222		}
223	}
224	return (0);
225}
226
227/**
228 * MainParseArgs
229 *	Parse a given argument vector. Called from main() and from
230 *	Main_ParseArgLine() when the .MAKEFLAGS target is used.
231 *
232 *	XXX: Deal with command line overriding .MAKEFLAGS in makefile
233 *
234 * Side Effects:
235 *	Various global and local flags will be set depending on the flags
236 *	given
237 */
238static void
239MainParseArgs(int argc, char **argv)
240{
241	int c;
242	Boolean	found_dd = FALSE;
243
244rearg:
245	optind = 1;	/* since we're called more than once */
246	optreset = 1;
247#define OPTFLAGS "ABC:D:E:I:PSV:Xd:ef:ij:km:nqrstvx:"
248	for (;;) {
249		if ((optind < argc) && strcmp(argv[optind], "--") == 0) {
250			found_dd = TRUE;
251		}
252		if ((c = getopt(argc, argv, OPTFLAGS)) == -1) {
253			break;
254		}
255		switch(c) {
256
257		case 'A':
258			arch_fatal = FALSE;
259			MFLAGS_append("-A", NULL);
260			break;
261		case 'C':
262			if (chdir(optarg) == -1)
263				err(1, "chdir %s", optarg);
264			break;
265		case 'D':
266			Var_Set(optarg, "1", VAR_GLOBAL);
267			MFLAGS_append("-D", optarg);
268			break;
269		case 'I':
270			Parse_AddIncludeDir(optarg);
271			MFLAGS_append("-I", optarg);
272			break;
273		case 'V':
274			Lst_AtEnd(&variables, estrdup(optarg));
275			MFLAGS_append("-V", optarg);
276			break;
277		case 'X':
278			expandVars = FALSE;
279			break;
280		case 'B':
281			compatMake = TRUE;
282			MFLAGS_append("-B", NULL);
283			unsetenv("MAKE_JOBS_FIFO");
284			break;
285		case 'P':
286			usePipes = FALSE;
287			MFLAGS_append("-P", NULL);
288			break;
289		case 'S':
290			keepgoing = FALSE;
291			MFLAGS_append("-S", NULL);
292			break;
293		case 'd': {
294			char *modules = optarg;
295
296			for (; *modules; ++modules)
297				switch (*modules) {
298				case 'A':
299					debug = ~0;
300					break;
301				case 'a':
302					debug |= DEBUG_ARCH;
303					break;
304				case 'c':
305					debug |= DEBUG_COND;
306					break;
307				case 'd':
308					debug |= DEBUG_DIR;
309					break;
310				case 'f':
311					debug |= DEBUG_FOR;
312					break;
313				case 'g':
314					if (modules[1] == '1') {
315						debug |= DEBUG_GRAPH1;
316						++modules;
317					}
318					else if (modules[1] == '2') {
319						debug |= DEBUG_GRAPH2;
320						++modules;
321					}
322					break;
323				case 'j':
324					debug |= DEBUG_JOB;
325					break;
326				case 'l':
327					debug |= DEBUG_LOUD;
328					break;
329				case 'm':
330					debug |= DEBUG_MAKE;
331					break;
332				case 's':
333					debug |= DEBUG_SUFF;
334					break;
335				case 't':
336					debug |= DEBUG_TARG;
337					break;
338				case 'v':
339					debug |= DEBUG_VAR;
340					break;
341				default:
342					warnx("illegal argument to d option "
343					    "-- %c", *modules);
344					usage();
345				}
346			MFLAGS_append("-d", optarg);
347			break;
348		}
349		case 'E':
350			Lst_AtEnd(&envFirstVars, estrdup(optarg));
351			MFLAGS_append("-E", optarg);
352			break;
353		case 'e':
354			checkEnvFirst = TRUE;
355			MFLAGS_append("-e", NULL);
356			break;
357		case 'f':
358			Lst_AtEnd(&makefiles, estrdup(optarg));
359			break;
360		case 'i':
361			ignoreErrors = TRUE;
362			MFLAGS_append("-i", NULL);
363			break;
364		case 'j': {
365			char *endptr;
366
367			forceJobs = TRUE;
368			maxJobs = strtol(optarg, &endptr, 10);
369			if (maxJobs <= 0 || *endptr != '\0') {
370				warnx("illegal number, -j argument -- %s",
371				    optarg);
372				usage();
373			}
374			MFLAGS_append("-j", optarg);
375			break;
376		}
377		case 'k':
378			keepgoing = TRUE;
379			MFLAGS_append("-k", NULL);
380			break;
381		case 'm':
382			Path_AddDir(&sysIncPath, optarg);
383			MFLAGS_append("-m", optarg);
384			break;
385		case 'n':
386			noExecute = TRUE;
387			MFLAGS_append("-n", NULL);
388			break;
389		case 'q':
390			queryFlag = TRUE;
391			/* Kind of nonsensical, wot? */
392			MFLAGS_append("-q", NULL);
393			break;
394		case 'r':
395			noBuiltins = TRUE;
396			MFLAGS_append("-r", NULL);
397			break;
398		case 's':
399			beSilent = TRUE;
400			MFLAGS_append("-s", NULL);
401			break;
402		case 't':
403			touchFlag = TRUE;
404			MFLAGS_append("-t", NULL);
405			break;
406		case 'v':
407			beVerbose = TRUE;
408			MFLAGS_append("-v", NULL);
409			break;
410		case 'x':
411			if (Main_ParseWarn(optarg, 1) != -1)
412				MFLAGS_append("-x", optarg);
413			break;
414
415		default:
416		case '?':
417			usage();
418		}
419	}
420	argv += optind;
421	argc -= optind;
422
423	oldVars = TRUE;
424
425	/*
426	 * Parse the rest of the arguments.
427	 *	o Check for variable assignments and perform them if so.
428	 *	o Check for more flags and restart getopt if so.
429	 *      o Anything else is taken to be a target and added
430	 *	  to the end of the "create" list.
431	 */
432	for (; *argv != NULL; ++argv, --argc) {
433		if (Parse_IsVar(*argv)) {
434			char *ptr = MAKEFLAGS_quote(*argv);
435
436			Var_Append(MAKEFLAGS, ptr, VAR_GLOBAL);
437			Parse_DoVar(*argv, VAR_CMD);
438			free(ptr);
439
440		} else if ((*argv)[0] == '-') {
441			if ((*argv)[1] == '\0') {
442				/*
443				 * (*argv) is a single dash, so we
444				 * just ignore it.
445				 */
446			} else if (found_dd) {
447				/*
448				 * Double dash has been found, ignore
449				 * any more options.  But what do we do
450				 * with it?  For now treat it like a target.
451				 */
452				Lst_AtEnd(&create, estrdup(*argv));
453			} else {
454				/*
455				 * (*argv) is a -flag, so backup argv and
456				 * argc.  getopt() expects options to start
457				 * in the 2nd position.
458				 */
459				argc++;
460				argv--;
461				goto rearg;
462			}
463
464		} else if ((*argv)[0] == '\0') {
465			Punt("illegal (null) argument.");
466
467		} else {
468			Lst_AtEnd(&create, estrdup(*argv));
469		}
470	}
471}
472
473/**
474 * Main_ParseArgLine
475 *  	Used by the parse module when a .MFLAGS or .MAKEFLAGS target
476 *	is encountered and by main() when reading the .MAKEFLAGS envariable.
477 *	Takes a line of arguments and breaks it into its
478 * 	component words and passes those words and the number of them to the
479 *	MainParseArgs function.
480 *	The line should have all its leading whitespace removed.
481 *
482 * Side Effects:
483 *	Only those that come from the various arguments.
484 */
485void
486Main_ParseArgLine(char *line, int mflags)
487{
488	char **argv;			/* Manufactured argument vector */
489	int argc;			/* Number of arguments in argv */
490
491	if (line == NULL)
492		return;
493	for (; *line == ' '; ++line)
494		continue;
495	if (!*line)
496		return;
497
498	if (mflags)
499		argv = MAKEFLAGS_break(line, &argc);
500	else
501		argv = brk_string(line, &argc, TRUE);
502
503	MainParseArgs(argc, argv);
504}
505
506char *
507chdir_verify_path(const char *path, char *obpath)
508{
509	struct stat sb;
510
511	if (stat(path, &sb) == 0 && S_ISDIR(sb.st_mode)) {
512		if (chdir(path) == -1 || getcwd(obpath, MAXPATHLEN) == NULL) {
513			warn("warning: %s", path);
514			return (NULL);
515		}
516		return (obpath);
517	}
518
519	return (NULL);
520}
521
522static void
523catch_child(int sig __unused)
524{
525}
526
527/*
528 * In lieu of a good way to prevent every possible looping in
529 * make(1), stop there from being more than MKLVL_MAXVAL processes forked
530 * by make(1), to prevent a forkbomb from happening, in a dumb and
531 * mechanical way.
532 */
533static void
534check_make_level(void)
535{
536#ifdef WANT_ENV_MKLVL
537	char	*value = getenv(MKLVL_ENVVAR);
538	int	level = (value == NULL) ? 0 : atoi(value);
539
540	if (level < 0) {
541		errc(2, EAGAIN, "Invalid value for recursion level (%d).",
542		    level);
543	} else if (level > MKLVL_MAXVAL) {
544		errc(2, EAGAIN, "Max recursion level (%d) exceeded.",
545		    MKLVL_MAXVAL);
546	} else {
547		char new_value[32];
548		sprintf(new_value, "%d", level + 1);
549		setenv(MKLVL_ENVVAR, new_value, 1);
550	}
551#endif /* WANT_ENV_MKLVL */
552}
553
554/**
555 * main
556 *	The main function, for obvious reasons. Initializes variables
557 *	and a few modules, then parses the arguments give it in the
558 *	environment and on the command line. Reads the system makefile
559 *	followed by either Makefile, makefile or the file given by the
560 *	-f argument. Sets the .MAKEFLAGS PMake variable based on all the
561 *	flags it has received by then uses either the Make or the Compat
562 *	module to create the initial list of targets.
563 *
564 * Results:
565 *	If -q was given, exits -1 if anything was out-of-date. Else it exits
566 *	0.
567 *
568 * Side Effects:
569 *	The program exits when done. Targets are created. etc. etc. etc.
570 */
571int
572main(int argc, char **argv)
573{
574	Boolean outOfDate = TRUE; 	/* FALSE if all targets up to date */
575	char *p, *p1, *pathp;
576	char *path;
577	char mdpath[MAXPATHLEN];
578	char obpath[MAXPATHLEN];
579	char cdpath[MAXPATHLEN];
580    	const char *machine = getenv("MACHINE");
581	const char *machine_arch = getenv("MACHINE_ARCH");
582	const char *machine_cpu = getenv("MACHINE_CPU");
583	char *cp = NULL, *start;
584
585	/* avoid faults on read-only strings */
586	static char syspath[] = PATH_DEFSYSPATH;
587
588	{
589	/*
590	 * Catch SIGCHLD so that we get kicked out of select() when we
591	 * need to look at a child.  This is only known to matter for the
592	 * -j case (perhaps without -P).
593	 *
594	 * XXX this is intentionally misplaced.
595	 */
596	struct sigaction sa;
597
598	sigemptyset(&sa.sa_mask);
599	sa.sa_flags = SA_RESTART | SA_NOCLDSTOP;
600	sa.sa_handler = catch_child;
601	sigaction(SIGCHLD, &sa, NULL);
602	}
603
604	check_make_level();
605
606#if DEFSHELL == 2
607	/*
608	 * Turn off ENV to make ksh happier.
609	 */
610	unsetenv("ENV");
611#endif
612
613#ifdef RLIMIT_NOFILE
614	/*
615	 * get rid of resource limit on file descriptors
616	 */
617	{
618		struct rlimit rl;
619		if (getrlimit(RLIMIT_NOFILE, &rl) != -1 &&
620		    rl.rlim_cur != rl.rlim_max) {
621			rl.rlim_cur = rl.rlim_max;
622			setrlimit(RLIMIT_NOFILE, &rl);
623		}
624	}
625#endif
626
627	/*
628	 * PC-98 kernel sets the `i386' string to the utsname.machine and
629	 * it cannot be distinguished from IBM-PC by uname(3).  Therefore,
630	 * we check machine.ispc98 and adjust the machine variable before
631	 * using usname(3) below.
632	 * NOTE: machdep.ispc98 was defined on 1998/8/31. At that time,
633	 * __FreeBSD_version was defined as 300003. So, this check can
634	 * safely be done with any kernel with version > 300003.
635	 */
636	if (!machine) {
637		int	ispc98;
638		size_t	len;
639
640		len = sizeof(ispc98);
641		if (!sysctlbyname("machdep.ispc98", &ispc98, &len, NULL, 0)) {
642			if (ispc98)
643				machine = "pc98";
644		}
645	}
646
647	/*
648	 * Get the name of this type of MACHINE from utsname
649	 * so we can share an executable for similar machines.
650	 * (i.e. m68k: amiga hp300, mac68k, sun3, ...)
651	 *
652	 * Note that while MACHINE is decided at run-time,
653	 * MACHINE_ARCH is always known at compile time.
654	 */
655	if (!machine) {
656#ifndef MACHINE
657		static struct utsname utsname;
658
659		if (uname(&utsname) == -1)
660			err(2, "uname");
661		machine = utsname.machine;
662#else
663		machine = MACHINE;
664#endif
665	}
666
667	if (!machine_arch) {
668#ifndef MACHINE_ARCH
669		machine_arch = "unknown";
670#else
671		machine_arch = MACHINE_ARCH;
672#endif
673	}
674
675	/*
676	 * Set machine_cpu to the minumum supported CPU revision based
677	 * on the target architecture, if not already set.
678	 */
679	if (!machine_cpu) {
680		if (!strcmp(machine_arch, "i386"))
681			machine_cpu = "i386";
682		else if (!strcmp(machine_arch, "alpha"))
683			machine_cpu = "ev4";
684		else
685			machine_cpu = "unknown";
686	}
687
688	expandVars = TRUE;
689	beSilent = FALSE;		/* Print commands as executed */
690	ignoreErrors = FALSE;		/* Pay attention to non-zero returns */
691	noExecute = FALSE;		/* Execute all commands */
692	keepgoing = FALSE;		/* Stop on error */
693	allPrecious = FALSE;		/* Remove targets when interrupted */
694	queryFlag = FALSE;		/* This is not just a check-run */
695	noBuiltins = FALSE;		/* Read the built-in rules */
696	touchFlag = FALSE;		/* Actually update targets */
697	usePipes = TRUE;		/* Catch child output in pipes */
698	debug = 0;			/* No debug verbosity, please. */
699	jobsRunning = FALSE;
700
701	maxJobs = DEFMAXJOBS;
702	forceJobs = FALSE;              /* No -j flag */
703	compatMake = FALSE;		/* No compat mode */
704
705	/*
706	 * Initialize the parsing, directory and variable modules to prepare
707	 * for the reading of inclusion paths and variable settings on the
708	 * command line
709	 */
710	Dir_Init();		/* Initialize directory structures so -I flags
711				 * can be processed correctly */
712	Var_Init(environ);	/* As well as the lists of variables for
713				 * parsing arguments */
714        str_init();
715
716	/*
717	 * Initialize various variables.
718	 *	MAKE also gets this name, for compatibility
719	 *	.MAKEFLAGS gets set to the empty string just in case.
720	 *	MFLAGS also gets initialized empty, for compatibility.
721	 */
722	Var_Set("MAKE", argv[0], VAR_GLOBAL);
723	Var_Set(MAKEFLAGS, "", VAR_GLOBAL);
724	Var_Set("MFLAGS", "", VAR_GLOBAL);
725	Var_Set("MACHINE", machine, VAR_GLOBAL);
726	Var_Set("MACHINE_ARCH", machine_arch, VAR_GLOBAL);
727	Var_Set("MACHINE_CPU", machine_cpu, VAR_GLOBAL);
728#ifdef MAKE_VERSION
729	Var_Set("MAKE_VERSION", MAKE_VERSION, VAR_GLOBAL);
730#endif
731
732	/*
733	 * First snag things out of the MAKEFLAGS environment
734	 * variable.  Then parse the command line arguments.
735	 */
736	Main_ParseArgLine(getenv("MAKEFLAGS"), 1);
737
738	MainParseArgs(argc, argv);
739
740	/*
741	 * Find where we are...
742	 */
743	curdir = cdpath;
744	if (getcwd(curdir, MAXPATHLEN) == NULL)
745		err(2, NULL);
746
747	{
748	struct stat sa;
749
750	if (stat(curdir, &sa) == -1)
751	    err(2, "%s", curdir);
752	}
753
754	/*
755	 * The object directory location is determined using the
756	 * following order of preference:
757	 *
758	 *	1. MAKEOBJDIRPREFIX`cwd`
759	 *	2. MAKEOBJDIR
760	 *	3. PATH_OBJDIR.${MACHINE}
761	 *	4. PATH_OBJDIR
762	 *	5. PATH_OBJDIRPREFIX`cwd`
763	 *
764	 * If one of the first two fails, use the current directory.
765	 * If the remaining three all fail, use the current directory.
766	 *
767	 * Once things are initted,
768	 * have to add the original directory to the search path,
769	 * and modify the paths for the Makefiles apropriately.  The
770	 * current directory is also placed as a variable for make scripts.
771	 */
772	if (!(pathp = getenv("MAKEOBJDIRPREFIX"))) {
773		if (!(path = getenv("MAKEOBJDIR"))) {
774			path = PATH_OBJDIR;
775			pathp = PATH_OBJDIRPREFIX;
776			snprintf(mdpath, MAXPATHLEN, "%s.%s",
777					path, machine);
778			if (!(objdir = chdir_verify_path(mdpath, obpath)))
779				if (!(objdir=chdir_verify_path(path, obpath))) {
780					snprintf(mdpath, MAXPATHLEN,
781							"%s%s", pathp, curdir);
782					if (!(objdir=chdir_verify_path(mdpath,
783								       obpath)))
784						objdir = curdir;
785				}
786		}
787		else if (!(objdir = chdir_verify_path(path, obpath)))
788			objdir = curdir;
789	}
790	else {
791		snprintf(mdpath, MAXPATHLEN, "%s%s", pathp, curdir);
792		if (!(objdir = chdir_verify_path(mdpath, obpath)))
793			objdir = curdir;
794	}
795	Dir_InitDot();		/* Initialize the "." directory */
796	if (objdir != curdir)
797		Path_AddDir(&dirSearchPath, curdir);
798	Var_Set(".ST_EXPORTVAR", "YES", VAR_GLOBAL);
799	Var_Set(".CURDIR", curdir, VAR_GLOBAL);
800	Var_Set(".OBJDIR", objdir, VAR_GLOBAL);
801
802	if (getenv("MAKE_JOBS_FIFO") != NULL)
803		forceJobs = TRUE;
804	/*
805	 * Be compatible if user did not specify -j and did not explicitly
806	 * turned compatibility on
807	 */
808	if (!compatMake && !forceJobs)
809		compatMake = TRUE;
810
811	/*
812	 * Initialize target and suffix modules in preparation for
813	 * parsing the makefile(s)
814	 */
815	Targ_Init();
816	Suff_Init();
817
818	DEFAULT = NULL;
819	time(&now);
820
821	/*
822	 * Set up the .TARGETS variable to contain the list of targets to be
823	 * created. If none specified, make the variable empty -- the parser
824	 * will fill the thing in with the default or .MAIN target.
825	 */
826	if (!Lst_IsEmpty(&create)) {
827		LstNode *ln;
828
829		for (ln = Lst_First(&create); ln != NULL; ln = Lst_Succ(ln)) {
830			char *name = Lst_Datum(ln);
831
832			Var_Append(".TARGETS", name, VAR_GLOBAL);
833		}
834	} else
835		Var_Set(".TARGETS", "", VAR_GLOBAL);
836
837
838	/*
839	 * If no user-supplied system path was given (through the -m option)
840	 * add the directories from the DEFSYSPATH (more than one may be given
841	 * as dir1:...:dirn) to the system include path.
842	 */
843	if (TAILQ_EMPTY(&sysIncPath)) {
844		for (start = syspath; *start != '\0'; start = cp) {
845			for (cp = start; *cp != '\0' && *cp != ':'; cp++)
846				continue;
847			if (*cp == '\0') {
848				Path_AddDir(&sysIncPath, start);
849			} else {
850				*cp++ = '\0';
851				Path_AddDir(&sysIncPath, start);
852			}
853		}
854	}
855
856	/*
857	 * Read in the built-in rules first, followed by the specified
858	 * makefile, if it was (makefile != (char *) NULL), or the default
859	 * Makefile and makefile, in that order, if it wasn't.
860	 */
861	if (!noBuiltins) {
862		/* Path of sys.mk */
863		Lst sysMkPath = Lst_Initializer(sysMkPath);
864		LstNode *ln;
865
866		Path_Expand(PATH_DEFSYSMK, &sysIncPath, &sysMkPath);
867		if (Lst_IsEmpty(&sysMkPath))
868			Fatal("make: no system rules (%s).", PATH_DEFSYSMK);
869		LST_FOREACH(ln, &sysMkPath) {
870			if (!ReadMakefile(Lst_Datum(ln)))
871				break;
872		}
873		if (ln != NULL)
874			Fatal("make: cannot open %s.", (char *)Lst_Datum(ln));
875		Lst_Destroy(&sysMkPath, free);
876	}
877
878	if (!Lst_IsEmpty(&makefiles)) {
879		LstNode *ln;
880
881		LST_FOREACH(ln, &makefiles) {
882			if (!ReadMakefile(Lst_Datum(ln)))
883				break;
884		}
885		if (ln != NULL)
886			Fatal("make: cannot open %s.", (char *)Lst_Datum(ln));
887	} else if (!ReadMakefile("BSDmakefile"))
888	    if (!ReadMakefile("makefile"))
889		ReadMakefile("Makefile");
890
891	ReadMakefile(".depend");
892
893	/* Install all the flags into the MAKE envariable. */
894	if (((p = Var_Value(MAKEFLAGS, VAR_GLOBAL, &p1)) != NULL) && *p)
895		setenv("MAKEFLAGS", p, 1);
896	free(p1);
897
898	/*
899	 * For compatibility, look at the directories in the VPATH variable
900	 * and add them to the search path, if the variable is defined. The
901	 * variable's value is in the same format as the PATH envariable, i.e.
902	 * <directory>:<directory>:<directory>...
903	 */
904	if (Var_Exists("VPATH", VAR_CMD)) {
905		/*
906		 * GCC stores string constants in read-only memory, but
907		 * Var_Subst will want to write this thing, so store it
908		 * in an array
909		 */
910		static char VPATH[] = "${VPATH}";
911		Buffer	*buf;
912		char	*vpath;
913		char	*ptr;
914		char	savec;
915
916		buf = Var_Subst(VPATH, VAR_CMD, FALSE);
917
918		vpath = Buf_Data(buf);
919		do {
920			/* skip to end of directory */
921			for (ptr = vpath; *ptr != ':' && *ptr != '\0'; ptr++)
922				;
923
924			/* Save terminator character so know when to stop */
925			savec = *ptr;
926			*ptr = '\0';
927
928			/* Add directory to search path */
929			Path_AddDir(&dirSearchPath, vpath);
930
931			vpath = ptr + 1;
932		} while (savec != '\0');
933
934		Buf_Destroy(buf, TRUE);
935	}
936
937	/*
938	 * Now that all search paths have been read for suffixes et al, it's
939	 * time to add the default search path to their lists...
940	 */
941	Suff_DoPaths();
942
943	/* print the initial graph, if the user requested it */
944	if (DEBUG(GRAPH1))
945		Targ_PrintGraph(1);
946
947	/* print the values of any variables requested by the user */
948	if (Lst_IsEmpty(&variables)) {
949		/*
950		 * Since the user has not requested that any variables
951		 * be printed, we can build targets.
952		 *
953		 * Have read the entire graph and need to make a list of targets
954		 * to create. If none was given on the command line, we consult
955		 * the parsing module to find the main target(s) to create.
956		 */
957		Lst targs = Lst_Initializer(targs);
958
959		if (Lst_IsEmpty(&create))
960			Parse_MainName(&targs);
961		else
962			Targ_FindList(&targs, &create, TARG_CREATE);
963
964		if (compatMake) {
965			/*
966			 * Compat_Init will take care of creating
967			 * all the targets as well as initializing
968			 * the module.
969			 */
970			Compat_Run(&targs);
971			outOfDate = 0;
972		} else {
973			/*
974			 * Initialize job module before traversing
975			 * the graph, now that any .BEGIN and .END
976			 * targets have been read.  This is done
977			 * only if the -q flag wasn't given (to
978			 * prevent the .BEGIN from being executed
979			 * should it exist).
980			 */
981			if (!queryFlag) {
982				Job_Init(maxJobs);
983				jobsRunning = TRUE;
984			}
985
986			/* Traverse the graph, checking on all the targets */
987			outOfDate = Make_Run(&targs);
988		}
989		Lst_Destroy(&targs, NOFREE);
990
991	} else {
992		/*
993		 * Print the values of any variables requested by
994		 * the user.
995		 */
996		LstNode		*n;
997		const char	*name;
998		char		*v;
999		char		*value;
1000
1001		LST_FOREACH(n, &variables) {
1002			name = Lst_Datum(n);
1003			if (expandVars) {
1004				v = emalloc(strlen(name) + 1 + 3);
1005				sprintf(v, "${%s}", name);
1006
1007				value = Buf_Peel(Var_Subst(v,
1008				    VAR_GLOBAL, FALSE));
1009				printf("%s\n", value);
1010
1011				free(v);
1012				free(value);
1013			} else {
1014				value = Var_Value(name, VAR_GLOBAL, &v);
1015				printf("%s\n", value != NULL ? value : "");
1016				if (v != NULL)
1017					free(v);
1018			}
1019		}
1020	}
1021
1022	Lst_Destroy(&variables, free);
1023	Lst_Destroy(&makefiles, free);
1024	Lst_Destroy(&create, free);
1025
1026	/* print the graph now it's been processed if the user requested it */
1027	if (DEBUG(GRAPH2))
1028		Targ_PrintGraph(2);
1029
1030	if (queryFlag && outOfDate)
1031		return (1);
1032	else
1033		return (0);
1034}
1035
1036/**
1037 * ReadMakefile
1038 *	Open and parse the given makefile.
1039 *
1040 * Results:
1041 *	TRUE if ok. FALSE if couldn't open file.
1042 *
1043 * Side Effects:
1044 *	lots
1045 */
1046static Boolean
1047ReadMakefile(const char *p)
1048{
1049	char *fname;			/* makefile to read */
1050	FILE *stream;
1051	char *name, path[MAXPATHLEN];
1052	char *MAKEFILE;
1053	int setMAKEFILE;
1054
1055	/* XXX - remove this once constification is done */
1056	fname = estrdup(p);
1057
1058	if (!strcmp(fname, "-")) {
1059		Parse_File("(stdin)", stdin);
1060		Var_Set("MAKEFILE", "", VAR_GLOBAL);
1061	} else {
1062		setMAKEFILE = strcmp(fname, ".depend");
1063
1064		/* if we've chdir'd, rebuild the path name */
1065		if (curdir != objdir && *fname != '/') {
1066			snprintf(path, MAXPATHLEN, "%s/%s", curdir, fname);
1067			/*
1068			 * XXX The realpath stuff breaks relative includes
1069			 * XXX in some cases.   The problem likely is in
1070			 * XXX parse.c where it does special things in
1071			 * XXX ParseDoInclude if the file is relateive
1072			 * XXX or absolute and not a system file.  There
1073			 * XXX it assumes that if the current file that's
1074			 * XXX being included is absolute, that any files
1075			 * XXX that it includes shouldn't do the -I path
1076			 * XXX stuff, which is inconsistant with historical
1077			 * XXX behavior.  However, I can't pentrate the mists
1078			 * XXX further, so I'm putting this workaround in
1079			 * XXX here until such time as the underlying bug
1080			 * XXX can be fixed.
1081			 */
1082#if THIS_BREAKS_THINGS
1083			if (realpath(path, path) != NULL &&
1084			    (stream = fopen(path, "r")) != NULL) {
1085				MAKEFILE = fname;
1086				fname = path;
1087				goto found;
1088			}
1089		} else if (realpath(fname, path) != NULL) {
1090			MAKEFILE = fname;
1091			fname = path;
1092			if ((stream = fopen(fname, "r")) != NULL)
1093				goto found;
1094		}
1095#else
1096			if ((stream = fopen(path, "r")) != NULL) {
1097				MAKEFILE = fname;
1098				fname = path;
1099				goto found;
1100			}
1101		} else {
1102			MAKEFILE = fname;
1103			if ((stream = fopen(fname, "r")) != NULL)
1104				goto found;
1105		}
1106#endif
1107		/* look in -I and system include directories. */
1108		name = Path_FindFile(fname, &parseIncPath);
1109		if (!name)
1110			name = Path_FindFile(fname, &sysIncPath);
1111		if (!name || !(stream = fopen(name, "r")))
1112			return (FALSE);
1113		MAKEFILE = fname = name;
1114		/*
1115		 * set the MAKEFILE variable desired by System V fans -- the
1116		 * placement of the setting here means it gets set to the last
1117		 * makefile specified, as it is set by SysV make.
1118		 */
1119found:
1120		if (setMAKEFILE)
1121			Var_Set("MAKEFILE", MAKEFILE, VAR_GLOBAL);
1122		Parse_File(fname, stream);
1123		fclose(stream);
1124	}
1125	return (TRUE);
1126}
1127
1128/*
1129 * usage --
1130 *	exit with usage message
1131 */
1132static void
1133usage(void)
1134{
1135	fprintf(stderr, "%s\n%s\n%s\n%s\n",
1136"usage: make [-ABPSXeiknqrstv] [-C directory] [-D variable] [-d flags]",
1137"            [-E variable] [-f makefile] [-I directory] [-j max_jobs]",
1138"            [-m directory] [-V variable] [variable=value] [-x warn_flag]",
1139"            [target ...]");
1140	exit(2);
1141}
1142