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
7 * This code is derived from software contributed to Berkeley by
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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
38 * @(#) Copyright (c) 1988, 1989, 1990, 1993 The Regents of the University of California. All rights reserved.
39 * @(#)main.c 8.3 (Berkeley) 3/19/94
40 * $FreeBSD: src/usr.bin/make/main.c,v 1.118 2005/02/13 13:33:56 harti Exp $
41 * $DragonFly: src/usr.bin/make/main.c,v 1.64 2005/03/19 00:19:55 okumoto Exp $
46 * The main file for this entire program. Exit routines etc
49 * Utility functions defined in this file:
50 * Main_ParseArgLine Takes a line of arguments, breaks them and
51 * treats them as if they were given when first
52 * invoked. Used by the parse module to implement
57 #include <sys/utsname.h>
59 #include <sys/param.h>
62 #include <sys/resource.h>
81 #include "pathnames.h"
88 #define WANT_ENV_MKLVL 1
89 #define MKLVL_MAXVAL 500
90 #define MKLVL_ENVVAR "__MKLVL__"
92 #define MAKEFLAGS ".MAKEFLAGS"
94 /* Targets to be made */
95 Lst create = Lst_Initializer(create);
97 time_t now; /* Time at start of make */
98 struct GNode *DEFAULT; /* .DEFAULT node */
99 Boolean allPrecious; /* .PRECIOUS given on line by itself */
101 static Boolean noBuiltins; /* -r flag */
103 /* ordered list of makefiles to read */
104 static Lst makefiles = Lst_Initializer(makefiles);
106 static Boolean expandVars; /* fully expand printed variables */
108 /* list of variables to print */
109 static Lst variables = Lst_Initializer(variables);
111 int maxJobs; /* -j argument */
112 static Boolean forceJobs; /* -j argument given */
113 Boolean compatMake; /* -B argument */
114 Boolean debug; /* -d flag */
115 Boolean noExecute; /* -n flag */
116 Boolean keepgoing; /* -k flag */
117 Boolean queryFlag; /* -q flag */
118 Boolean touchFlag; /* -t flag */
119 Boolean usePipes; /* !-P flag */
120 Boolean ignoreErrors; /* -i flag */
121 Boolean beSilent; /* -s flag */
122 Boolean beVerbose; /* -v flag */
123 Boolean oldVars; /* variable substitution style */
124 Boolean checkEnvFirst; /* -e flag */
126 /* (-E) vars to override from env */
127 Lst envFirstVars = Lst_Initializer(envFirstVars);
129 Boolean jobsRunning; /* TRUE if the jobs might be running */
131 static void MainParseArgs(int, char **);
132 char *chdir_verify_path(const char *, char *);
133 static int ReadMakefile(const char *);
134 static void usage(void);
136 static char *curdir; /* startup directory */
137 static char *objdir; /* where we chdir'ed to */
140 * Append a flag with an optional argument to MAKEFLAGS and MFLAGS
143 MFLAGS_append(const char *flag, char *arg)
147 Var_Append(MAKEFLAGS, flag, VAR_GLOBAL);
149 str = MAKEFLAGS_quote(arg);
150 Var_Append(MAKEFLAGS, str, VAR_GLOBAL);
154 Var_Append("MFLAGS", flag, VAR_GLOBAL);
156 str = MAKEFLAGS_quote(arg);
157 Var_Append("MFLAGS", str, VAR_GLOBAL);
164 * Parse a given argument vector. Called from main() and from
165 * Main_ParseArgLine() when the .MAKEFLAGS target is used.
167 * XXX: Deal with command line overriding .MAKEFLAGS in makefile
173 * Various global and local flags will be set depending on the flags
177 MainParseArgs(int argc, char **argv)
181 optind = 1; /* since we're called more than once */
182 #define OPTFLAGS "BC:D:E:I:PSV:Xd:ef:ij:km:nqrstv"
183 rearg: while((c = getopt(argc, argv, OPTFLAGS)) != -1) {
186 if (chdir(optarg) == -1)
187 err(1, "chdir %s", optarg);
190 Var_Set(optarg, "1", VAR_GLOBAL);
191 MFLAGS_append("-D", optarg);
194 Parse_AddIncludeDir(optarg);
195 MFLAGS_append("-I", optarg);
198 Lst_AtEnd(&variables, estrdup(optarg));
199 MFLAGS_append("-V", optarg);
206 MFLAGS_append("-B", NULL);
207 unsetenv("MAKE_JOBS_FIFO");
211 MFLAGS_append("-P", NULL);
215 MFLAGS_append("-S", NULL);
218 char *modules = optarg;
220 for (; *modules; ++modules)
238 if (modules[1] == '1') {
239 debug |= DEBUG_GRAPH1;
242 else if (modules[1] == '2') {
243 debug |= DEBUG_GRAPH2;
266 warnx("illegal argument to d option -- %c", *modules);
269 MFLAGS_append("-d", optarg);
273 Lst_AtEnd(&envFirstVars, estrdup(optarg));
274 MFLAGS_append("-E", optarg);
277 checkEnvFirst = TRUE;
278 MFLAGS_append("-e", NULL);
281 Lst_AtEnd(&makefiles, estrdup(optarg));
285 MFLAGS_append("-i", NULL);
291 maxJobs = strtol(optarg, &endptr, 10);
292 if (maxJobs <= 0 || *endptr != '\0') {
293 warnx("illegal number, -j argument -- %s",
297 MFLAGS_append("-j", optarg);
302 MFLAGS_append("-k", NULL);
305 Dir_AddDir(&sysIncPath, optarg);
306 MFLAGS_append("-m", optarg);
310 MFLAGS_append("-n", NULL);
314 /* Kind of nonsensical, wot? */
315 MFLAGS_append("-q", NULL);
319 MFLAGS_append("-r", NULL);
323 MFLAGS_append("-s", NULL);
327 MFLAGS_append("-t", NULL);
331 MFLAGS_append("-v", NULL);
342 * See if the rest of the arguments are variable assignments and
343 * perform them if so. Else take them to be targets and stuff them
344 * on the end of the "create" list.
346 for (argv += optind, argc -= optind; *argv; ++argv, --argc)
347 if (Parse_IsVar(*argv)) {
348 char *ptr = MAKEFLAGS_quote(*argv);
350 Var_Append(MAKEFLAGS, ptr, VAR_GLOBAL);
353 Parse_DoVar(*argv, VAR_CMD);
356 Punt("illegal (null) argument.");
359 optind = 0; /* -flag... */
364 Lst_AtEnd(&create, estrdup(*argv));
369 * Main_ParseArgLine --
370 * Used by the parse module when a .MFLAGS or .MAKEFLAGS target
371 * is encountered and by main() when reading the .MAKEFLAGS envariable.
372 * Takes a line of arguments and breaks it into its
373 * component words and passes those words and the number of them to the
374 * MainParseArgs function.
375 * The line should have all its leading whitespace removed.
381 * Only those that come from the various arguments.
384 Main_ParseArgLine(char *line, int mflags)
386 char **argv; /* Manufactured argument vector */
387 int argc; /* Number of arguments in argv */
391 for (; *line == ' '; ++line)
397 argv = MAKEFLAGS_break(line, &argc);
399 argv = brk_string(line, &argc, TRUE);
401 MainParseArgs(argc, argv);
405 chdir_verify_path(const char *path, char *obpath)
409 if (stat(path, &sb) == 0 && S_ISDIR(sb.st_mode)) {
410 if (chdir(path) == -1 || getcwd(obpath, MAXPATHLEN) == NULL) {
411 warn("warning: %s", path);
421 catch_child(int sig __unused)
426 * In lieu of a good way to prevent every possible looping in
427 * make(1), stop there from being more than MKLVL_MAXVAL processes forked
428 * by make(1), to prevent a forkbomb from happening, in a dumb and
432 check_make_level(void)
434 #ifdef WANT_ENV_MKLVL
435 char *value = getenv(MKLVL_ENVVAR);
436 int level = (value == NULL) ? 0 : atoi(value);
439 errc(2, EAGAIN, "Invalid value for recursion level (%d).", level);
440 } else if (level > MKLVL_MAXVAL) {
441 errc(2, EAGAIN, "Max recursion level (%d) exceeded.", MKLVL_MAXVAL);
444 sprintf(new_value, "%d", level + 1);
445 setenv(MKLVL_ENVVAR, new_value, 1);
447 #endif /* WANT_ENV_MKLVL */
452 * The main function, for obvious reasons. Initializes variables
453 * and a few modules, then parses the arguments give it in the
454 * environment and on the command line. Reads the system makefile
455 * followed by either Makefile, makefile or the file given by the
456 * -f argument. Sets the .MAKEFLAGS PMake variable based on all the
457 * flags it has received by then uses either the Make or the Compat
458 * module to create the initial list of targets.
461 * If -q was given, exits -1 if anything was out-of-date. Else it exits
465 * The program exits when done. Targets are created. etc. etc. etc.
468 main(int argc, char **argv)
470 Boolean outOfDate = TRUE; /* FALSE if all targets up to date */
474 char mdpath[MAXPATHLEN];
475 char obpath[MAXPATHLEN];
476 char cdpath[MAXPATHLEN];
477 const char *machine = getenv("MACHINE");
478 const char *machine_arch = getenv("MACHINE_ARCH");
479 const char *machine_cpu = getenv("MACHINE_CPU");
480 char *cp = NULL, *start;
482 /* avoid faults on read-only strings */
483 static char syspath[] = PATH_DEFSYSPATH;
487 * Catch SIGCHLD so that we get kicked out of select() when we
488 * need to look at a child. This is only known to matter for the
489 * -j case (perhaps without -P).
491 * XXX this is intentionally misplaced.
495 sigemptyset(&sa.sa_mask);
496 sa.sa_flags = SA_RESTART | SA_NOCLDSTOP;
497 sa.sa_handler = catch_child;
498 sigaction(SIGCHLD, &sa, NULL);
505 * Turn off ENV to make ksh happier.
512 * get rid of resource limit on file descriptors
516 if (getrlimit(RLIMIT_NOFILE, &rl) != -1 &&
517 rl.rlim_cur != rl.rlim_max) {
518 rl.rlim_cur = rl.rlim_max;
519 setrlimit(RLIMIT_NOFILE, &rl);
524 * Get the name of this type of MACHINE from utsname
525 * so we can share an executable for similar machines.
526 * (i.e. m68k: amiga hp300, mac68k, sun3, ...)
528 * Note that while MACHINE is decided at run-time,
529 * MACHINE_ARCH is always known at compile time.
533 static struct utsname utsname;
535 if (uname(&utsname) == -1)
537 machine = utsname.machine;
545 machine_arch = "unknown";
547 machine_arch = MACHINE_ARCH;
552 * Set machine_cpu to the minumum supported CPU revision based
553 * on the target architecture, if not already set.
556 if (!strcmp(machine_arch, "i386"))
557 machine_cpu = "i386";
558 else if (!strcmp(machine_arch, "alpha"))
561 machine_cpu = "unknown";
565 beSilent = FALSE; /* Print commands as executed */
566 ignoreErrors = FALSE; /* Pay attention to non-zero returns */
567 noExecute = FALSE; /* Execute all commands */
568 keepgoing = FALSE; /* Stop on error */
569 allPrecious = FALSE; /* Remove targets when interrupted */
570 queryFlag = FALSE; /* This is not just a check-run */
571 noBuiltins = FALSE; /* Read the built-in rules */
572 touchFlag = FALSE; /* Actually update targets */
573 usePipes = TRUE; /* Catch child output in pipes */
574 debug = 0; /* No debug verbosity, please. */
577 maxJobs = DEFMAXJOBS;
578 forceJobs = FALSE; /* No -j flag */
579 compatMake = FALSE; /* No compat mode */
582 * Initialize the parsing, directory and variable modules to prepare
583 * for the reading of inclusion paths and variable settings on the
586 Dir_Init(); /* Initialize directory structures so -I flags
587 * can be processed correctly */
588 Parse_Init(); /* Need to initialize the paths of #include
590 Var_Init(); /* As well as the lists of variables for
591 * parsing arguments */
595 * Initialize various variables.
596 * MAKE also gets this name, for compatibility
597 * .MAKEFLAGS gets set to the empty string just in case.
598 * MFLAGS also gets initialized empty, for compatibility.
600 Var_Set("MAKE", argv[0], VAR_GLOBAL);
601 Var_Set(MAKEFLAGS, "", VAR_GLOBAL);
602 Var_Set("MFLAGS", "", VAR_GLOBAL);
603 Var_Set("MACHINE", machine, VAR_GLOBAL);
604 Var_Set("MACHINE_ARCH", machine_arch, VAR_GLOBAL);
605 Var_Set("MACHINE_CPU", machine_cpu, VAR_GLOBAL);
607 Var_Set("MAKE_VERSION", MAKE_VERSION, VAR_GLOBAL);
611 * First snag any flags out of the MAKE environment variable.
612 * (Note this is *not* MAKEFLAGS since /bin/make uses that and it's
613 * in a different format).
615 Main_ParseArgLine(getenv("MAKEFLAGS"), 1);
617 MainParseArgs(argc, argv);
620 * Find where we are...
621 * All this code is so that we know where we are when we start up
622 * on a different machine with pmake.
625 if (getcwd(curdir, MAXPATHLEN) == NULL)
631 if (stat(curdir, &sa) == -1)
632 err(2, "%s", curdir);
636 * The object directory location is determined using the
637 * following order of preference:
639 * 1. MAKEOBJDIRPREFIX`cwd`
641 * 3. PATH_OBJDIR.${MACHINE}
643 * 5. PATH_OBJDIRPREFIX`cwd`
645 * If one of the first two fails, use the current directory.
646 * If the remaining three all fail, use the current directory.
648 * Once things are initted,
649 * have to add the original directory to the search path,
650 * and modify the paths for the Makefiles apropriately. The
651 * current directory is also placed as a variable for make scripts.
653 if (!(pathp = getenv("MAKEOBJDIRPREFIX"))) {
654 if (!(path = getenv("MAKEOBJDIR"))) {
656 pathp = PATH_OBJDIRPREFIX;
657 snprintf(mdpath, MAXPATHLEN, "%s.%s",
659 if (!(objdir = chdir_verify_path(mdpath, obpath)))
660 if (!(objdir=chdir_verify_path(path, obpath))) {
661 snprintf(mdpath, MAXPATHLEN,
662 "%s%s", pathp, curdir);
663 if (!(objdir=chdir_verify_path(mdpath,
668 else if (!(objdir = chdir_verify_path(path, obpath)))
672 snprintf(mdpath, MAXPATHLEN, "%s%s", pathp, curdir);
673 if (!(objdir = chdir_verify_path(mdpath, obpath)))
676 Dir_InitDot(); /* Initialize the "." directory */
677 if (objdir != curdir)
678 Dir_AddDir(&dirSearchPath, curdir);
679 Var_Set(".DIRECTIVE_MAKEENV", "YES", VAR_GLOBAL);
680 Var_Set(".CURDIR", curdir, VAR_GLOBAL);
681 Var_Set(".OBJDIR", objdir, VAR_GLOBAL);
683 if (getenv("MAKE_JOBS_FIFO") != NULL)
686 * Be compatible if user did not specify -j and did not explicitly
687 * turned compatibility on
689 if (!compatMake && !forceJobs)
693 * Initialize archive, target and suffix modules in preparation for
694 * parsing the makefile(s)
704 * Set up the .TARGETS variable to contain the list of targets to be
705 * created. If none specified, make the variable empty -- the parser
706 * will fill the thing in with the default or .MAIN target.
708 if (!Lst_IsEmpty(&create)) {
711 for (ln = Lst_First(&create); ln != NULL; ln = Lst_Succ(ln)) {
712 char *name = Lst_Datum(ln);
714 Var_Append(".TARGETS", name, VAR_GLOBAL);
717 Var_Set(".TARGETS", "", VAR_GLOBAL);
721 * If no user-supplied system path was given (through the -m option)
722 * add the directories from the DEFSYSPATH (more than one may be given
723 * as dir1:...:dirn) to the system include path.
725 if (Lst_IsEmpty(&sysIncPath)) {
726 for (start = syspath; *start != '\0'; start = cp) {
727 for (cp = start; *cp != '\0' && *cp != ':'; cp++)
730 Dir_AddDir(&sysIncPath, start);
733 Dir_AddDir(&sysIncPath, start);
739 * Read in the built-in rules first, followed by the specified
740 * makefile, if it was (makefile != (char *) NULL), or the default
741 * Makefile and makefile, in that order, if it wasn't.
745 Lst sysMkPath = Lst_Initializer(sysMkPath);
748 Dir_Expand(PATH_DEFSYSMK, &sysIncPath, &sysMkPath);
749 if (Lst_IsEmpty(&sysMkPath))
750 Fatal("make: no system rules (%s).", PATH_DEFSYSMK);
751 LST_FOREACH(ln, &sysMkPath) {
752 if (!ReadMakefile(Lst_Datum(ln)))
756 Fatal("make: cannot open %s.", (char *)Lst_Datum(ln));
757 Lst_Destroy(&sysMkPath, free);
760 if (!Lst_IsEmpty(&makefiles)) {
763 LST_FOREACH(ln, &makefiles) {
764 if (!ReadMakefile(Lst_Datum(ln)))
768 Fatal("make: cannot open %s.", (char *)Lst_Datum(ln));
769 } else if (!ReadMakefile("BSDmakefile"))
770 if (!ReadMakefile("makefile"))
771 ReadMakefile("Makefile");
773 ReadMakefile(".depend");
775 /* Install all the flags into the MAKE envariable. */
776 if (((p = Var_Value(MAKEFLAGS, VAR_GLOBAL, &p1)) != NULL) && *p)
777 setenv("MAKEFLAGS", p, 1);
781 * For compatibility, look at the directories in the VPATH variable
782 * and add them to the search path, if the variable is defined. The
783 * variable's value is in the same format as the PATH envariable, i.e.
784 * <directory>:<directory>:<directory>...
786 if (Var_Exists("VPATH", VAR_CMD)) {
788 * GCC stores string constants in read-only memory, but
789 * Var_Subst will want to write this thing, so store it
792 static char VPATH[] = "${VPATH}";
798 buf = Var_Subst(NULL, VPATH, VAR_CMD, FALSE);
800 vpath = Buf_Data(buf);
802 /* skip to end of directory */
803 for (ptr = vpath; *ptr != ':' && *ptr != '\0'; ptr++)
806 /* Save terminator character so know when to stop */
810 /* Add directory to search path */
811 Dir_AddDir(&dirSearchPath, vpath);
814 } while (savec != '\0');
816 Buf_Destroy(buf, TRUE);
820 * Now that all search paths have been read for suffixes et al, it's
821 * time to add the default search path to their lists...
825 /* print the initial graph, if the user requested it */
829 /* print the values of any variables requested by the user */
830 if (Lst_IsEmpty(&variables)) {
832 * Since the user has not requested that any variables
833 * be printed, we can build targets.
835 * Have read the entire graph and need to make a list of targets
836 * to create. If none was given on the command line, we consult
837 * the parsing module to find the main target(s) to create.
839 Lst targs = Lst_Initializer(targs);
841 if (Lst_IsEmpty(&create))
842 Parse_MainName(&targs);
844 Targ_FindList(&targs, &create, TARG_CREATE);
848 * Compat_Init will take care of creating
849 * all the targets as well as initializing
856 * Initialize job module before traversing
857 * the graph, now that any .BEGIN and .END
858 * targets have been read. This is done
859 * only if the -q flag wasn't given (to
860 * prevent the .BEGIN from being executed
868 /* Traverse the graph, checking on all the targets */
869 outOfDate = Make_Run(&targs);
871 Lst_Destroy(&targs, NOFREE);
875 * Print the values of any variables requested by
880 LST_FOREACH(n, &variables) {
881 const char *name = Lst_Datum(n);
886 v = emalloc(strlen(name) + 1 + 3);
887 sprintf(v, "${%s}", name);
889 value = Buf_Peel(Var_Subst(NULL, v,
891 printf("%s\n", value);
898 value = Var_Value(name, VAR_GLOBAL, &v);
899 printf("%s\n", value != NULL ? value : "");
906 Lst_Destroy(&variables, free);
907 Lst_Destroy(&makefiles, free);
908 Lst_Destroy(&create, free);
910 /* print the graph now it's been processed if the user requested it */
914 if (queryFlag && outOfDate)
922 * Open and parse the given makefile.
925 * TRUE if ok. FALSE if couldn't open file.
931 ReadMakefile(const char *p)
933 char *fname; /* makefile to read */
935 char *name, path[MAXPATHLEN];
939 /* XXX - remove this once constification is done */
942 if (!strcmp(fname, "-")) {
943 Parse_File("(stdin)", stdin);
944 Var_Set("MAKEFILE", "", VAR_GLOBAL);
946 setMAKEFILE = strcmp(fname, ".depend");
948 /* if we've chdir'd, rebuild the path name */
949 if (curdir != objdir && *fname != '/') {
950 snprintf(path, MAXPATHLEN, "%s/%s", curdir, fname);
952 * XXX The realpath stuff breaks relative includes
953 * XXX in some cases. The problem likely is in
954 * XXX parse.c where it does special things in
955 * XXX ParseDoInclude if the file is relateive
956 * XXX or absolute and not a system file. There
957 * XXX it assumes that if the current file that's
958 * XXX being included is absolute, that any files
959 * XXX that it includes shouldn't do the -I path
960 * XXX stuff, which is inconsistant with historical
961 * XXX behavior. However, I can't pentrate the mists
962 * XXX further, so I'm putting this workaround in
963 * XXX here until such time as the underlying bug
966 #if THIS_BREAKS_THINGS
967 if (realpath(path, path) != NULL &&
968 (stream = fopen(path, "r")) != NULL) {
973 } else if (realpath(fname, path) != NULL) {
976 if ((stream = fopen(fname, "r")) != NULL)
980 if ((stream = fopen(path, "r")) != NULL) {
987 if ((stream = fopen(fname, "r")) != NULL)
991 /* look in -I and system include directories. */
992 name = Dir_FindFile(fname, &parseIncPath);
994 name = Dir_FindFile(fname, &sysIncPath);
995 if (!name || !(stream = fopen(name, "r")))
997 MAKEFILE = fname = name;
999 * set the MAKEFILE variable desired by System V fans -- the
1000 * placement of the setting here means it gets set to the last
1001 * makefile specified, as it is set by SysV make.
1005 Var_Set("MAKEFILE", MAKEFILE, VAR_GLOBAL);
1006 Parse_File(fname, stream);
1014 * Execute the command in cmd, and return the output of that command
1018 * A string containing the output of the command, or the empty string
1019 * If error is not NULL, it contains the reason for the command failure
1022 * The string must be freed by the caller.
1025 Cmd_Exec(const char *cmd, const char **error)
1027 int fds[2]; /* Pipe streams */
1028 int cpid; /* Child PID */
1029 int pid; /* PID from wait() */
1030 int status; /* command exit status */
1031 Buffer *buf; /* buffer to store the result */
1037 if (shellPath == NULL)
1040 * Open a pipe for fetching its output
1042 if (pipe(fds) == -1) {
1043 *error = "Couldn't create pipe for \"%s\"";
1050 switch (cpid = vfork()) {
1053 * Close input side of pipe
1058 * Duplicate the output stream to the shell's output, then
1059 * shut the extra thing down. Note we don't fetch the error
1060 * stream...why not? Why?
1068 /* Set up arguments for shell */
1069 args[0] = shellName;
1074 execv(shellPath, args);
1080 *error = "Couldn't exec \"%s\"";
1085 * No need for the writing half
1090 char result[BUFSIZ];
1091 rcnt = read(fds[0], result, sizeof(result));
1093 Buf_AddBytes(buf, (size_t)rcnt, (Byte *)result);
1094 } while (rcnt > 0 || (rcnt == -1 && errno == EINTR));
1097 *error = "Error reading shell's output for \"%s\"";
1100 * Close the input side of the pipe.
1105 * Wait for the process to exit.
1107 while (((pid = wait(&status)) != cpid) && (pid >= 0))
1111 *error = "\"%s\" returned non-zero status";
1113 Buf_StripNewlines(buf);
1122 * exit with usage message
1127 fprintf(stderr, "%s\n%s\n%s\n",
1128 "usage: make [-BPSXeiknqrstv] [-C directory] [-D variable] [-d flags]",
1129 " [-E variable] [-f makefile] [-I directory] [-j max_jobs]",
1130 " [-m directory] [-V variable] [variable=value] [target ...]");