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mkdep.c revision 1.41
      1  1.41      jmmv /* $NetBSD: mkdep.c,v 1.41 2012/08/26 22:37:19 jmmv Exp $ */
      2   1.1      tron 
      3   1.1      tron /*-
      4   1.1      tron  * Copyright (c) 1999 The NetBSD Foundation, Inc.
      5   1.1      tron  * All rights reserved.
      6   1.1      tron  *
      7   1.1      tron  * This code is derived from software contributed to The NetBSD Foundation
      8   1.1      tron  * by Matthias Scheler.
      9   1.1      tron  *
     10   1.1      tron  * Redistribution and use in source and binary forms, with or without
     11   1.1      tron  * modification, are permitted provided that the following conditions
     12   1.1      tron  * are met:
     13   1.1      tron  * 1. Redistributions of source code must retain the above copyright
     14   1.1      tron  *    notice, this list of conditions and the following disclaimer.
     15   1.1      tron  * 2. Redistributions in binary form must reproduce the above copyright
     16   1.1      tron  *    notice, this list of conditions and the following disclaimer in the
     17   1.1      tron  *    documentation and/or other materials provided with the distribution.
     18   1.1      tron  *
     19   1.1      tron  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20   1.1      tron  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21   1.1      tron  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22   1.8       cgd  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23   1.1      tron  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24   1.1      tron  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25   1.1      tron  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26   1.1      tron  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27   1.1      tron  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28   1.1      tron  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29   1.1      tron  * POSSIBILITY OF SUCH DAMAGE.
     30   1.1      tron  */
     31   1.1      tron 
     32  1.17     lukem #if HAVE_NBTOOL_CONFIG_H
     33  1.17     lukem #include "nbtool_config.h"
     34  1.17     lukem #endif
     35  1.17     lukem 
     36   1.1      tron #include <sys/cdefs.h>
     37  1.17     lukem #if !defined(lint)
     38  1.32     lukem __COPYRIGHT("@(#) Copyright (c) 1999 The NetBSD Foundation, Inc.\
     39  1.32     lukem  All rights reserved.");
     40  1.41      jmmv __RCSID("$NetBSD: mkdep.c,v 1.41 2012/08/26 22:37:19 jmmv Exp $");
     41   1.1      tron #endif /* not lint */
     42  1.10        tv 
     43  1.18       dsl #include <sys/mman.h>
     44   1.1      tron #include <sys/param.h>
     45   1.1      tron #include <sys/wait.h>
     46   1.1      tron #include <ctype.h>
     47  1.10        tv #include <err.h>
     48  1.18       dsl #include <fcntl.h>
     49  1.36  christos #include <getopt.h>
     50   1.1      tron #include <locale.h>
     51   1.1      tron #include <paths.h>
     52   1.1      tron #include <stdio.h>
     53   1.1      tron #include <stdlib.h>
     54   1.1      tron #include <string.h>
     55   1.1      tron #include <unistd.h>
     56   1.1      tron 
     57  1.11    simonb #include "findcc.h"
     58  1.11    simonb 
     59  1.21       dsl typedef struct opt opt_t;
     60  1.21       dsl struct opt {
     61  1.21       dsl 	opt_t	*left;
     62  1.21       dsl 	opt_t	*right;
     63  1.21       dsl 	int	len;
     64  1.21       dsl 	int	count;
     65  1.21       dsl 	char	name[4];
     66  1.21       dsl };
     67  1.21       dsl 
     68  1.37  christos typedef struct suff_list {
     69  1.33     lukem 	size_t	len;
     70  1.37  christos 	char	*suff;
     71  1.37  christos 	struct suff_list *next;
     72  1.22       dsl } suff_list_t;
     73  1.22       dsl 
     74  1.21       dsl /* tree of includes for -o processing */
     75  1.40     joerg static opt_t *opt;
     76  1.40     joerg static int width;
     77  1.21       dsl 
     78   1.1      tron #define DEFAULT_PATH		_PATH_DEFPATH
     79   1.1      tron #define DEFAULT_FILENAME	".depend"
     80   1.1      tron 
     81  1.21       dsl static void save_for_optional(const char *, const char *);
     82  1.21       dsl static int write_optional(int, opt_t *, int);
     83  1.21       dsl 
     84  1.18       dsl static inline void *
     85  1.18       dsl deconst(const void *p)
     86  1.18       dsl {
     87  1.18       dsl 	return (const char *)p - (const char *)0 + (char *)0;
     88  1.18       dsl }
     89   1.1      tron 
     90  1.40     joerg __dead static void
     91  1.18       dsl usage(void)
     92   1.1      tron {
     93   1.1      tron 	(void)fprintf(stderr,
     94  1.41      jmmv 	    "usage: %s [-aDdopq] [-f file] [-P prefix] [-s suffixes] "
     95  1.41      jmmv 	    "-- [flags] file ...\n",
     96   1.6       cgd 	    getprogname());
     97   1.1      tron 	exit(EXIT_FAILURE);
     98   1.1      tron }
     99   1.1      tron 
    100  1.18       dsl static int
    101  1.18       dsl run_cc(int argc, char **argv, const char **fname)
    102  1.12   msaitoh {
    103  1.28  christos 	const char *CC, *tmpdir;
    104  1.29  christos 	char * volatile pathname;
    105  1.18       dsl 	static char tmpfilename[MAXPATHLEN];
    106  1.18       dsl 	char **args;
    107  1.18       dsl 	int tmpfd;
    108  1.18       dsl 	pid_t pid, cpid;
    109  1.18       dsl 	int status;
    110   1.1      tron 
    111   1.1      tron 	if ((CC = getenv("CC")) == NULL)
    112   1.1      tron 		CC = DEFAULT_CC;
    113   1.1      tron 	if ((pathname = findcc(CC)) == NULL)
    114   1.1      tron 		if (!setenv("PATH", DEFAULT_PATH, 1))
    115   1.1      tron 			pathname = findcc(CC);
    116  1.18       dsl 	if (pathname == NULL)
    117  1.18       dsl 		err(EXIT_FAILURE, "%s: not found", CC);
    118  1.18       dsl 	if ((args = malloc((argc + 3) * sizeof(char *))) == NULL)
    119  1.18       dsl 		err(EXIT_FAILURE, "malloc");
    120   1.1      tron 
    121  1.18       dsl 	args[0] = deconst(CC);
    122  1.18       dsl 	args[1] = deconst("-M");
    123   1.1      tron 	(void)memcpy(&args[2], argv, (argc + 1) * sizeof(char *));
    124   1.1      tron 
    125   1.4    kleink 	if ((tmpdir = getenv("TMPDIR")) == NULL)
    126   1.4    kleink 		tmpdir = _PATH_TMP;
    127   1.4    kleink 	(void)snprintf(tmpfilename, sizeof (tmpfilename), "%s/%s", tmpdir,
    128   1.4    kleink 	    "mkdepXXXXXX");
    129  1.37  christos 	if ((tmpfd = mkstemp(tmpfilename)) < 0)
    130  1.37  christos 		err(EXIT_FAILURE,  "Unable to create temporary file %s",
    131  1.37  christos 		    tmpfilename);
    132  1.18       dsl 	(void)unlink(tmpfilename);
    133  1.18       dsl 	*fname = tmpfilename;
    134   1.1      tron 
    135   1.1      tron 	switch (cpid = vfork()) {
    136   1.1      tron 	case 0:
    137   1.7       cgd 		(void)dup2(tmpfd, STDOUT_FILENO);
    138   1.7       cgd 		(void)close(tmpfd);
    139   1.1      tron 
    140   1.7       cgd 		(void)execv(pathname, args);
    141   1.7       cgd 		_exit(EXIT_FAILURE);
    142   1.7       cgd 		/* NOTREACHED */
    143   1.1      tron 
    144   1.1      tron 	case -1:
    145  1.18       dsl 		err(EXIT_FAILURE, "unable to fork");
    146   1.1      tron 	}
    147   1.1      tron 
    148  1.27      elad 	free(pathname);
    149  1.27      elad 	free(args);
    150  1.27      elad 
    151   1.7       cgd 	while (((pid = wait(&status)) != cpid) && (pid >= 0))
    152   1.7       cgd 		continue;
    153   1.1      tron 
    154  1.18       dsl 	if (status)
    155  1.18       dsl 		errx(EXIT_FAILURE, "compile failed.");
    156  1.18       dsl 
    157  1.18       dsl 	return tmpfd;
    158  1.18       dsl }
    159  1.18       dsl 
    160  1.25       dsl static const char *
    161  1.25       dsl read_fname(void)
    162  1.25       dsl {
    163  1.25       dsl 	static char *fbuf;
    164  1.25       dsl 	static int fbuflen;
    165  1.25       dsl 	int len, ch;
    166  1.25       dsl 
    167  1.25       dsl 	for (len = 0; (ch = getchar()) != EOF; len++) {
    168  1.25       dsl 		if (isspace(ch)) {
    169  1.25       dsl 			if (len != 0)
    170  1.25       dsl 				break;
    171  1.25       dsl 			len--;
    172  1.25       dsl 			continue;
    173  1.25       dsl 		}
    174  1.25       dsl 		if (len >= fbuflen - 1) {
    175  1.25       dsl 			fbuf = realloc(fbuf, fbuflen += 32);
    176  1.25       dsl 			if (fbuf == NULL)
    177  1.25       dsl 				err(EXIT_FAILURE, "no memory");
    178  1.25       dsl 		}
    179  1.25       dsl 		fbuf[len] = ch;
    180  1.25       dsl 	}
    181  1.25       dsl 	if (len == 0)
    182  1.25       dsl 		return NULL;
    183  1.25       dsl 	fbuf[len] = 0;
    184  1.25       dsl 	return fbuf;
    185  1.25       dsl }
    186  1.25       dsl 
    187  1.36  christos static struct option longopt[] = {
    188  1.36  christos 	{ "sysroot", 1, NULL, 'R' },
    189  1.36  christos 	{ NULL, 0, NULL, '\0' },
    190  1.36  christos };
    191  1.36  christos 
    192  1.37  christos static void
    193  1.37  christos addsuff(suff_list_t **l, const char *s, size_t len)
    194  1.37  christos {
    195  1.37  christos 	suff_list_t *p = calloc(1, sizeof(*p));
    196  1.37  christos 	if (p == NULL)
    197  1.37  christos 		err(1, "calloc");
    198  1.37  christos 	p->suff = malloc(len + 1);
    199  1.37  christos 	if (p->suff == NULL)
    200  1.37  christos 		err(1, "malloc");
    201  1.37  christos 	memcpy(p->suff, s, len);
    202  1.37  christos 	p->suff[len] = '\0';
    203  1.37  christos 	p->len = len;
    204  1.37  christos 	p->next = *l;
    205  1.37  christos 	*l = p;
    206  1.37  christos }
    207  1.37  christos 
    208  1.18       dsl int
    209  1.18       dsl main(int argc, char **argv)
    210  1.18       dsl {
    211  1.18       dsl 	int 	aflag, dflag, oflag, qflag;
    212  1.18       dsl 	const char *filename;
    213  1.18       dsl 	int	dependfile;
    214  1.20       dsl 	char	*buf, *lim, *ptr, *line, *suf, *colon, *eol;
    215  1.18       dsl 	int	ok_ind, ch;
    216  1.33     lukem 	size_t	sz;
    217  1.18       dsl 	int	fd;
    218  1.34  christos 	size_t  slen;
    219  1.18       dsl 	const char *fname;
    220  1.41      jmmv 	const char *prefix = NULL;
    221  1.22       dsl 	const char *suffixes = NULL, *s;
    222  1.22       dsl 	suff_list_t *suff_list = NULL, *sl;
    223  1.18       dsl 
    224  1.24        he 	suf = NULL;		/* XXXGCC -Wuninitialized [sun2] */
    225  1.24        he 	sl = NULL;		/* XXXGCC -Wuninitialized [sun2] */
    226  1.24        he 
    227  1.18       dsl 	setlocale(LC_ALL, "");
    228  1.18       dsl 	setprogname(argv[0]);
    229   1.1      tron 
    230  1.18       dsl 	aflag = O_WRONLY | O_APPEND | O_CREAT | O_TRUNC;
    231  1.18       dsl 	dflag = 0;
    232  1.18       dsl 	oflag = 0;
    233  1.18       dsl 	qflag = 0;
    234  1.18       dsl 	filename = DEFAULT_FILENAME;
    235  1.18       dsl 	dependfile = -1;
    236   1.1      tron 
    237  1.18       dsl 	opterr = 0;	/* stop getopt() bleating about errors. */
    238  1.20       dsl 	for (;;) {
    239  1.20       dsl 		ok_ind = optind;
    240  1.41      jmmv 		ch = getopt_long(argc, argv, "aDdf:oP:pqRs:", longopt, NULL);
    241  1.18       dsl 		switch (ch) {
    242  1.20       dsl 		case -1:
    243  1.20       dsl 			ok_ind = optind;
    244  1.20       dsl 			break;
    245  1.18       dsl 		case 'a':	/* Append to output file */
    246  1.18       dsl 			aflag &= ~O_TRUNC;
    247  1.18       dsl 			continue;
    248  1.25       dsl 		case 'D':	/* Process *.d files (don't run cc -M) */
    249  1.25       dsl 			dflag = 2;	/* Read names from stdin */
    250  1.25       dsl 			opterr = 1;
    251  1.25       dsl 			continue;
    252  1.18       dsl 		case 'd':	/* Process *.d files (don't run cc -M) */
    253  1.18       dsl 			dflag = 1;
    254  1.18       dsl 			opterr = 1;
    255  1.18       dsl 			continue;
    256  1.18       dsl 		case 'f':	/* Name of output file */
    257  1.18       dsl 			filename = optarg;
    258  1.18       dsl 			continue;
    259  1.39       wiz 		case 'o':	/* Mark dependent files .OPTIONAL */
    260  1.18       dsl 			oflag = 1;
    261  1.18       dsl 			continue;
    262  1.41      jmmv 		case 'P':	/* Prefix for each target filename */
    263  1.41      jmmv 			prefix = optarg;
    264  1.41      jmmv 			continue;
    265  1.18       dsl 		case 'p':	/* Program mode (x.o: -> x:) */
    266  1.18       dsl 			suffixes = "";
    267  1.18       dsl 			continue;
    268  1.18       dsl 		case 'q':	/* Quiet */
    269  1.18       dsl 			qflag = 1;
    270  1.18       dsl 			continue;
    271  1.36  christos 		case 'R':
    272  1.36  christos 			/* sysroot = optarg */
    273  1.36  christos 			continue;
    274  1.18       dsl 		case 's':	/* Suffix list */
    275  1.18       dsl 			suffixes = optarg;
    276  1.18       dsl 			continue;
    277  1.18       dsl 		default:
    278  1.18       dsl 			if (dflag)
    279  1.18       dsl 				usage();
    280  1.18       dsl 			/* Unknown arguments are passed to "${CC} -M" */
    281  1.18       dsl 			break;
    282  1.18       dsl 		}
    283  1.18       dsl 		break;
    284   1.1      tron 	}
    285   1.1      tron 
    286  1.18       dsl 	argc -= ok_ind;
    287  1.18       dsl 	argv += ok_ind;
    288  1.25       dsl 	if ((argc == 0 && !dflag) || (argc != 0 && dflag == 2))
    289  1.18       dsl 		usage();
    290   1.1      tron 
    291  1.22       dsl 	if (suffixes != NULL) {
    292  1.37  christos 		if (*suffixes) {
    293  1.37  christos 			for (s = suffixes; (sz = strcspn(s, ", ")) != 0;) {
    294  1.37  christos 				addsuff(&suff_list, s, sz);
    295  1.37  christos 				s += sz;
    296  1.37  christos 				while (*s && strchr(", ", *s))
    297  1.37  christos 					s++;
    298  1.37  christos 			}
    299  1.37  christos 		} else
    300  1.37  christos 			addsuff(&suff_list, "", 0);
    301  1.22       dsl 	}
    302  1.22       dsl 
    303  1.18       dsl 	dependfile = open(filename, aflag, 0666);
    304  1.18       dsl 	if (dependfile == -1)
    305  1.18       dsl 		err(EXIT_FAILURE, "unable to %s to file %s\n",
    306  1.18       dsl 		    aflag & O_TRUNC ? "write" : "append", filename);
    307  1.18       dsl 
    308  1.25       dsl 	while (dflag == 2 || *argv != NULL) {
    309  1.18       dsl 		if (dflag) {
    310  1.25       dsl 			if (dflag == 2) {
    311  1.25       dsl 				fname = read_fname();
    312  1.25       dsl 				if (fname == NULL)
    313  1.25       dsl 					break;
    314  1.25       dsl 			} else
    315  1.25       dsl 				fname = *argv++;
    316  1.18       dsl 			fd = open(fname, O_RDONLY, 0);
    317  1.18       dsl 			if (fd == -1) {
    318  1.18       dsl 				if (!qflag)
    319  1.18       dsl 					warn("ignoring %s", fname);
    320  1.18       dsl 				continue;
    321  1.18       dsl 			}
    322  1.18       dsl 		} else {
    323  1.18       dsl 			fd = run_cc(argc, argv, &fname);
    324  1.18       dsl 			/* consume all args... */
    325  1.25       dsl 			argv += argc;
    326  1.18       dsl 		}
    327   1.1      tron 
    328  1.18       dsl 		sz = lseek(fd, 0, SEEK_END);
    329  1.18       dsl 		if (sz == 0) {
    330  1.18       dsl 			close(fd);
    331  1.18       dsl 			continue;
    332   1.1      tron 		}
    333  1.18       dsl 		buf = mmap(NULL, sz, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
    334  1.18       dsl 		close(fd);
    335   1.1      tron 
    336  1.18       dsl 		if (buf == MAP_FAILED)
    337  1.25       dsl 			err(EXIT_FAILURE, "unable to mmap file %s", fname);
    338  1.20       dsl 		lim = buf + sz - 1;
    339  1.18       dsl 
    340  1.18       dsl 		/* Remove leading "./" from filenames */
    341  1.20       dsl 		for (ptr = buf; ptr < lim; ptr++) {
    342  1.20       dsl 			if (ptr[1] != '.' || ptr[2] != '/'
    343  1.20       dsl 			    || !isspace((unsigned char)ptr[0]))
    344  1.18       dsl 				continue;
    345  1.18       dsl 			ptr[1] = ' ';
    346  1.20       dsl 			ptr[2] = ' ';
    347   1.7       cgd 		}
    348   1.1      tron 
    349  1.20       dsl 		for (line = eol = buf; eol <= lim;) {
    350  1.20       dsl 			while (eol <= lim && *eol++ != '\n')
    351  1.22       dsl 				/* Find end of this line */
    352  1.20       dsl 				continue;
    353  1.19       dsl 			if (line == eol - 1) {
    354  1.18       dsl 				/* empty line - ignore */
    355  1.19       dsl 				line = eol;
    356  1.18       dsl 				continue;
    357  1.19       dsl 			}
    358  1.18       dsl 			if (eol[-2] == '\\')
    359  1.18       dsl 				/* Assemble continuation lines */
    360  1.18       dsl 				continue;
    361  1.20       dsl 			for (colon = line; *colon != ':'; colon++) {
    362  1.20       dsl 				if (colon >= eol) {
    363  1.20       dsl 					colon = NULL;
    364  1.20       dsl 					break;
    365  1.20       dsl 				}
    366  1.20       dsl 			}
    367  1.22       dsl 			if (isspace((unsigned char)*line) || colon == NULL) {
    368  1.21       dsl 				/* No dependency - just transcribe line */
    369  1.21       dsl 				write(dependfile, line, eol - line);
    370  1.21       dsl 				line = eol;
    371  1.21       dsl 				continue;
    372  1.21       dsl 			}
    373  1.22       dsl 			if (suff_list != NULL) {
    374  1.18       dsl 				/* Find the .o: */
    375  1.22       dsl 				/* First allow for any whitespace */
    376  1.29  christos 				for (suf = colon; suf > buf; suf--) {
    377  1.22       dsl 					if (!isspace((unsigned char)suf[-1]))
    378  1.22       dsl 						break;
    379  1.22       dsl 				}
    380  1.29  christos 				if (suf == buf)
    381  1.29  christos 					errx(EXIT_FAILURE,
    382  1.29  christos 					    "Corrupted file `%s'", fname);
    383  1.22       dsl 				/* Then look for any valid suffix */
    384  1.37  christos 				for (sl = suff_list; sl != NULL;
    385  1.37  christos 				    sl = sl->next) {
    386  1.38     enami 					if (sl->len && buf <= suf - sl->len &&
    387  1.37  christos 					    !memcmp(suf - sl->len, sl->suff,
    388  1.22       dsl 						    sl->len))
    389  1.18       dsl 						break;
    390  1.18       dsl 				}
    391  1.34  christos 				/*
    392  1.34  christos 				 * Not found, check for .o, since the
    393  1.34  christos 				 * original file will have it.
    394  1.34  christos 				 */
    395  1.37  christos 				if (sl == NULL) {
    396  1.34  christos 					if (memcmp(suf - 2, ".o", 2) == 0)
    397  1.34  christos 						slen = 2;
    398  1.34  christos 					else
    399  1.34  christos 						slen = 0;
    400  1.34  christos 				} else
    401  1.34  christos 					slen = sl->len;
    402  1.18       dsl 			}
    403  1.34  christos 			if (suff_list != NULL && slen != 0) {
    404  1.34  christos 				suf -= slen;
    405  1.37  christos 				for (sl = suff_list; sl != NULL; sl = sl->next)
    406  1.37  christos 				{
    407  1.22       dsl 					if (sl != suff_list)
    408  1.22       dsl 						write(dependfile, " ", 1);
    409  1.41      jmmv 					if (prefix != NULL)
    410  1.41      jmmv 						write(dependfile, prefix,
    411  1.41      jmmv 						    strlen(prefix));
    412  1.18       dsl 					write(dependfile, line, suf - line);
    413  1.22       dsl 					write(dependfile, sl->suff, sl->len);
    414  1.18       dsl 				}
    415  1.18       dsl 				write(dependfile, colon, eol - colon);
    416  1.41      jmmv 			} else {
    417  1.41      jmmv 				if (prefix != NULL)
    418  1.41      jmmv 					write(dependfile, prefix, strlen(prefix));
    419  1.18       dsl 				write(dependfile, line, eol - line);
    420  1.41      jmmv 			}
    421  1.18       dsl 
    422  1.21       dsl 			if (oflag)
    423  1.21       dsl 				save_for_optional(colon + 1, eol);
    424  1.19       dsl 			line = eol;
    425  1.18       dsl 		}
    426  1.18       dsl 		munmap(buf, sz);
    427   1.1      tron 	}
    428  1.21       dsl 
    429  1.21       dsl 	if (oflag && opt != NULL) {
    430  1.21       dsl 		write(dependfile, ".OPTIONAL:", 10);
    431  1.21       dsl 		width = 9;
    432  1.21       dsl 		sz = write_optional(dependfile, opt, 0);
    433  1.21       dsl 		/* 'depth' is about 39 for an i386 kernel */
    434  1.21       dsl 		/* fprintf(stderr, "Recursion depth %d\n", sz); */
    435  1.21       dsl 	}
    436  1.18       dsl 	close(dependfile);
    437   1.1      tron 
    438   1.7       cgd 	exit(EXIT_SUCCESS);
    439  1.21       dsl }
    440  1.21       dsl 
    441  1.21       dsl 
    442  1.21       dsl /*
    443  1.21       dsl  * Only save each file once - the kernel .depend is 3MB and there is
    444  1.21       dsl  * no point doubling its size.
    445  1.21       dsl  * The data seems to be 'random enough' so the simple binary tree
    446  1.21       dsl  * only has a reasonable depth.
    447  1.21       dsl  */
    448  1.21       dsl static void
    449  1.21       dsl save_for_optional(const char *start, const char *limit)
    450  1.21       dsl {
    451  1.21       dsl 	opt_t **l, *n;
    452  1.21       dsl 	const char *name, *end;
    453  1.21       dsl 	int c;
    454  1.21       dsl 
    455  1.21       dsl 	while (start < limit && strchr(" \t\n\\", *start))
    456  1.21       dsl 		start++;
    457  1.21       dsl 	for (name = start; ; name = end) {
    458  1.21       dsl 		while (name < limit && strchr(" \t\n\\", *name))
    459  1.21       dsl 			name++;
    460  1.21       dsl 		for (end = name; end < limit && !strchr(" \t\n\\", *end);)
    461  1.21       dsl 			end++;
    462  1.21       dsl 		if (name >= limit)
    463  1.21       dsl 			break;
    464  1.21       dsl 		if (end[-1] == 'c' && end[-2] == '.' && name == start)
    465  1.21       dsl 			/* ignore dependency on the files own .c */
    466  1.21       dsl 			continue;
    467  1.21       dsl 		for (l = &opt;;) {
    468  1.21       dsl 			n = *l;
    469  1.21       dsl 			if (n == NULL) {
    470  1.21       dsl 				n = malloc(sizeof *n + (end - name));
    471  1.21       dsl 				n->left = n->right = 0;
    472  1.21       dsl 				n->len = end - name;
    473  1.21       dsl 				n->count = 1;
    474  1.21       dsl 				n->name[0] = ' ';
    475  1.21       dsl 				memcpy(n->name + 1, name, end - name);
    476  1.21       dsl 				*l = n;
    477  1.21       dsl 				break;
    478  1.21       dsl 			}
    479  1.21       dsl 			c = (end - name) - n->len;
    480  1.21       dsl 			if (c == 0)
    481  1.21       dsl 				c = memcmp(n->name + 1, name, (end - name));
    482  1.21       dsl 			if (c == 0) {
    483  1.21       dsl 				/* Duplicate */
    484  1.21       dsl 				n->count++;
    485  1.21       dsl 				break;
    486  1.21       dsl 			}
    487  1.21       dsl 			if (c < 0)
    488  1.21       dsl 				l = &n->left;
    489  1.21       dsl 			else
    490  1.21       dsl 				l = &n->right;
    491  1.21       dsl 		}
    492  1.21       dsl 	}
    493  1.21       dsl }
    494  1.21       dsl 
    495  1.21       dsl static int
    496  1.21       dsl write_optional(int fd, opt_t *node, int depth)
    497  1.21       dsl {
    498  1.21       dsl 	int d1 = ++depth;
    499  1.21       dsl 
    500  1.21       dsl 	if (node->left)
    501  1.21       dsl 		d1 = write_optional(fd, node->left, d1);
    502  1.21       dsl 	if (width > 76 - node->len) {
    503  1.21       dsl 		write(fd, " \\\n ", 4);
    504  1.21       dsl 		width = 1;
    505  1.21       dsl 	}
    506  1.21       dsl 	width += 1 + node->len;
    507  1.21       dsl 	write(fd, node->name, 1 + node->len);
    508  1.21       dsl 	if (node->right)
    509  1.21       dsl 		depth = write_optional(fd, node->right, depth);
    510  1.21       dsl 	return d1 > depth ? d1 : depth;
    511   1.1      tron }
    512