Fix some mis-usages of NULL.
[dragonfly.git] / usr.bin / rdist / expand.c
1 /*
2  * Copyright (c) 1983, 1993
3  *      The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *      This product includes software developed by the University of
16  *      California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#)expand.c 8.1 (Berkeley) 6/9/93
34  * $FreeBSD: src/usr.bin/rdist/expand.c,v 1.8 1999/08/28 01:05:06 peter Exp $
35  * $DragonFly: src/usr.bin/rdist/expand.c,v 1.5 2007/11/25 18:10:07 swildner Exp $
36  */
37
38 #include "defs.h"
39
40 #define GAVSIZ  NCARGS / 6
41 #define LC '{'
42 #define RC '}'
43
44 #define sort()  qsort((char *)sortbase, &eargv[eargc] - sortbase, \
45                       sizeof(*sortbase), argcmp), sortbase = &eargv[eargc]
46
47 static char     shchars[] = "${[*?";
48
49 int     which;          /* bit mask of types to expand */
50 int     eargc;          /* expanded arg count */
51 char    **eargv;        /* expanded arg vectors */
52 char    *path;
53 char    *pathp;
54 char    *lastpathp;
55 char    *tilde;         /* "~user" if not expanding tilde, else "" */
56 char    *tpathp;
57 int     nleft;
58
59 int     expany;         /* any expansions done? */
60 char    *entp;
61 char    **sortbase;
62
63 static void     Cat(char *, char *);
64 static void     addpath(int);
65 static int      amatch(char *, char *);
66 static int      argcmp(const void *, const void *);
67 static int      execbrc(char *, char *);
68 static void     expsh(char *);
69 static void     expstr(char *);
70 static int      match(char *, char *);
71 static void     matchdir(char *);
72 static int      smatch(char *, char *);
73
74 /*
75  * Take a list of names and expand any macros, etc.
76  * wh = E_VARS if expanding variables.
77  * wh = E_SHELL if expanding shell characters.
78  * wh = E_TILDE if expanding `~'.
79  * or any of these or'ed together.
80  *
81  * Major portions of this were snarfed from csh/sh.glob.c.
82  */
83 struct namelist *
84 expand(struct namelist *list, int wh)
85 {
86         register struct namelist *nl, *prev;
87         register int n;
88         char pathbuf[BUFSIZ];
89         char *argvbuf[GAVSIZ];
90
91         if (debug) {
92                 printf("expand(%p, %d)\nlist = ", list, wh);
93                 prnames(list);
94         }
95
96         if (wh == 0) {
97                 register char *cp;
98
99                 for (nl = list; nl != NULL; nl = nl->n_next)
100                         for (cp = nl->n_name; *cp; cp++)
101                                 *cp = *cp & TRIM;
102                 return(list);
103         }
104
105         which = wh;
106         path = tpathp = pathp = pathbuf;
107         *pathp = '\0';
108         lastpathp = &path[sizeof pathbuf - 2];
109         tilde = "";
110         eargc = 0;
111         eargv = sortbase = argvbuf;
112         *eargv = 0;
113         nleft = NCARGS - 4;
114         /*
115          * Walk the name list and expand names into eargv[];
116          */
117         for (nl = list; nl != NULL; nl = nl->n_next)
118                 expstr(nl->n_name);
119         /*
120          * Take expanded list of names from eargv[] and build a new list.
121          */
122         list = prev = NULL;
123         for (n = 0; n < eargc; n++) {
124                 nl = makenl(NULL);
125                 nl->n_name = eargv[n];
126                 if (prev == NULL)
127                         list = prev = nl;
128                 else {
129                         prev->n_next = nl;
130                         prev = nl;
131                 }
132         }
133         if (debug) {
134                 printf("expanded list = ");
135                 prnames(list);
136         }
137         return(list);
138 }
139
140 static void
141 expstr(char *s)
142 {
143         register char *cp, *cp1;
144         register struct namelist *tp;
145         char *tail;
146         char buf[BUFSIZ];
147         int savec, oeargc;
148         extern char homedir[];
149
150         if (s == NULL || *s == '\0')
151                 return;
152
153         if ((which & E_VARS) && (cp = index(s, '$')) != NULL) {
154                 *cp++ = '\0';
155                 if (*cp == '\0') {
156                         yyerror("no variable name after '$'");
157                         return;
158                 }
159                 if (*cp == LC) {
160                         cp++;
161                         if ((tail = index(cp, RC)) == NULL) {
162                                 yyerror("unmatched '{'");
163                                 return;
164                         }
165                         *tail++ = savec = '\0';
166                         if (*cp == '\0') {
167                                 yyerror("no variable name after '$'");
168                                 return;
169                         }
170                 } else {
171                         tail = cp + 1;
172                         savec = *tail;
173                         *tail = '\0';
174                 }
175                 tp = lookup(cp, 0, NULL);
176                 if (savec != '\0')
177                         *tail = savec;
178                 if (tp != NULL) {
179                         for (; tp != NULL; tp = tp->n_next) {
180                                 snprintf(buf, sizeof(buf), 
181                                     "%s%s%s", s, tp->n_name, tail);
182                                 expstr(buf);
183                         }
184                         return;
185                 }
186                 snprintf(buf, sizeof(buf), "%s%s", s, tail);
187                 expstr(buf);
188                 return;
189         }
190         if ((which & ~E_VARS) == 0 || !strcmp(s, "{") || !strcmp(s, "{}")) {
191                 Cat(s, "");
192                 sort();
193                 return;
194         }
195         if (*s == '~') {
196                 cp = ++s;
197                 if (*cp == '\0' || *cp == '/') {
198                         tilde = "~";
199                         cp1 = homedir;
200                 } else {
201                         tilde = cp1 = buf;
202                         *cp1++ = '~';
203                         do
204                                 *cp1++ = *cp++;
205                         while (*cp && *cp != '/');
206                         *cp1 = '\0';
207                         if (pw == NULL || strcmp(pw->pw_name, buf+1) != 0) {
208                                 if ((pw = getpwnam(buf+1)) == NULL) {
209                                         strcat(buf, ": unknown user name");
210                                         yyerror(buf+1);
211                                         return;
212                                 }
213                         }
214                         cp1 = pw->pw_dir;
215                         s = cp;
216                 }
217                 for (cp = path; (*cp++ = *cp1++); )
218                         ;
219                 tpathp = pathp = cp - 1;
220         } else {
221                 tpathp = pathp = path;
222                 tilde = "";
223         }
224         *pathp = '\0';
225         if (!(which & E_SHELL)) {
226                 if (which & E_TILDE)
227                         Cat(path, s);
228                 else
229                         Cat(tilde, s);
230                 sort();
231                 return;
232         }
233         oeargc = eargc;
234         expany = 0;
235         expsh(s);
236         if (eargc == oeargc)
237                 Cat(s, "");             /* "nonomatch" is set */
238         sort();
239 }
240
241 static int
242 argcmp(const void *a1, const void *a2)
243 {
244
245         return (strcmp(*(char **)a1, *(char **)a2));
246 }
247
248 /*
249  * If there are any Shell meta characters in the name,
250  * expand into a list, after searching directory
251  */
252 static void
253 expsh(char *s)
254 {
255         register char *cp;
256         register char *spathp, *oldcp;
257         struct stat stb;
258
259         spathp = pathp;
260         cp = s;
261         while (!any(*cp, shchars)) {
262                 if (*cp == '\0') {
263                         if (!expany || stat(path, &stb) >= 0) {
264                                 if (which & E_TILDE)
265                                         Cat(path, "");
266                                 else
267                                         Cat(tilde, tpathp);
268                         }
269                         goto endit;
270                 }
271                 addpath(*cp++);
272         }
273         oldcp = cp;
274         while (cp > s && *cp != '/')
275                 cp--, pathp--;
276         if (*cp == '/')
277                 cp++, pathp++;
278         *pathp = '\0';
279         if (*oldcp == '{') {
280                 execbrc(cp, NULL);
281                 return;
282         }
283         matchdir(cp);
284 endit:
285         pathp = spathp;
286         *pathp = '\0';
287 }
288
289 static void
290 matchdir(char *pattern)
291 {
292         struct stat stb;
293         register struct dirent *dp;
294         DIR *dirp;
295
296         dirp = opendir(path);
297         if (dirp == NULL) {
298                 if (expany)
299                         return;
300                 goto patherr2;
301         }
302         if (fstat(dirp->dd_fd, &stb) < 0)
303                 goto patherr1;
304         if (!ISDIR(stb.st_mode)) {
305                 errno = ENOTDIR;
306                 goto patherr1;
307         }
308         while ((dp = readdir(dirp)) != NULL)
309                 if (match(dp->d_name, pattern)) {
310                         if (which & E_TILDE)
311                                 Cat(path, dp->d_name);
312                         else {
313                                 strcpy(pathp, dp->d_name);
314                                 Cat(tilde, tpathp);
315                                 *pathp = '\0';
316                         }
317                 }
318         closedir(dirp);
319         return;
320
321 patherr1:
322         closedir(dirp);
323 patherr2:
324         strcat(path, ": ");
325         strcat(path, strerror(errno));
326         yyerror(path);
327 }
328
329 static int
330 execbrc(char *p, char *s)
331 {
332         char restbuf[BUFSIZ + 2];
333         register char *pe, *pm, *pl;
334         int brclev;
335         char *lm, savec, *spathp;
336
337         brclev = 0;
338
339         for (lm = restbuf; *p != '{'; *lm++ = *p++)
340                 continue;
341         for (pe = ++p; *pe; pe++)
342                 switch (*pe) {
343
344                 case '{':
345                         brclev++;
346                         continue;
347
348                 case '}':
349                         if (brclev == 0)
350                                 goto pend;
351                         brclev--;
352                         continue;
353
354                 case '[':
355                         for (pe++; *pe && *pe != ']'; pe++)
356                                 continue;
357                         if (!*pe)
358                                 yyerror("Missing ']'");
359                         continue;
360                 }
361 pend:
362         if (brclev || !*pe) {
363                 yyerror("Missing '}'");
364                 return (0);
365         }
366         for (pl = pm = p; pm <= pe; pm++)
367                 switch (*pm & (QUOTE|TRIM)) {
368
369                 case '{':
370                         brclev++;
371                         continue;
372
373                 case '}':
374                         if (brclev) {
375                                 brclev--;
376                                 continue;
377                         }
378                         goto doit;
379
380                 case ',':
381                         if (brclev)
382                                 continue;
383 doit:
384                         savec = *pm;
385                         *pm = 0;
386                         strcpy(lm, pl);
387                         strcat(restbuf, pe + 1);
388                         *pm = savec;
389                         if (s == 0) {
390                                 spathp = pathp;
391                                 expsh(restbuf);
392                                 pathp = spathp;
393                                 *pathp = 0;
394                         } else if (amatch(s, restbuf))
395                                 return (1);
396                         sort();
397                         pl = pm + 1;
398                         continue;
399
400                 case '[':
401                         for (pm++; *pm && *pm != ']'; pm++)
402                                 continue;
403                         if (!*pm)
404                                 yyerror("Missing ']'");
405                         continue;
406                 }
407         return (0);
408 }
409
410 static int
411 match(char *s, char *p)
412 {
413         register int c;
414         register char *sentp;
415         char sexpany;
416
417         sexpany = expany;
418         if (*s == '.' && *p != '.')
419                 return (0);
420         sentp = entp;
421         entp = s;
422         c = amatch(s, p);
423         entp = sentp;
424         expany = sexpany;
425         return (c);
426 }
427
428 static int
429 amatch(register char *s, register char *p)
430 {
431         register int scc;
432         int ok, lc, c, cc;
433         char *spathp;
434         struct stat stb;
435
436         expany = 1;
437         for (;;) {
438                 scc = *s++ & TRIM;
439                 switch (c = *p++) {
440
441                 case '{':
442                         return (execbrc(p - 1, s - 1));
443
444                 case '[':
445                         ok = 0;
446                         lc = 077777;
447                         while ((cc = *p++)) {
448                                 if (cc == ']') {
449                                         if (ok)
450                                                 break;
451                                         return (0);
452                                 }
453                                 if (cc == '-') {
454                                         if (lc <= scc && scc <= *p++)
455                                                 ok++;
456                                 } else
457                                         if (scc == (lc = cc))
458                                                 ok++;
459                         }
460                         if (cc == 0) {
461                                 yyerror("Missing ']'");
462                                 return (0);
463                         }
464                         continue;
465
466                 case '*':
467                         if (!*p)
468                                 return (1);
469                         if (*p == '/') {
470                                 p++;
471                                 goto slash;
472                         }
473                         for (s--; *s; s++)
474                                 if (amatch(s, p))
475                                         return (1);
476                         return (0);
477
478                 case '\0':
479                         return (scc == '\0');
480
481                 default:
482                         if ((c & TRIM) != scc)
483                                 return (0);
484                         continue;
485
486                 case '?':
487                         if (scc == '\0')
488                                 return (0);
489                         continue;
490
491                 case '/':
492                         if (scc)
493                                 return (0);
494 slash:
495                         s = entp;
496                         spathp = pathp;
497                         while (*s)
498                                 addpath(*s++);
499                         addpath('/');
500                         if (stat(path, &stb) == 0 && ISDIR(stb.st_mode)) {
501                                 if (*p == '\0') {
502                                         if (which & E_TILDE)
503                                                 Cat(path, "");
504                                         else
505                                                 Cat(tilde, tpathp);
506                                 } else
507                                         expsh(p);
508                         }
509                         pathp = spathp;
510                         *pathp = '\0';
511                         return (0);
512                 }
513         }
514 }
515
516 static int
517 smatch(register char *s, register char *p)
518 {
519         register int scc;
520         int ok, lc, c, cc;
521
522         for (;;) {
523                 scc = *s++ & TRIM;
524                 switch (c = *p++) {
525
526                 case '[':
527                         ok = 0;
528                         lc = 077777;
529                         while ((cc = *p++)) {
530                                 if (cc == ']') {
531                                         if (ok)
532                                                 break;
533                                         return (0);
534                                 }
535                                 if (cc == '-') {
536                                         if (lc <= scc && scc <= *p++)
537                                                 ok++;
538                                 } else
539                                         if (scc == (lc = cc))
540                                                 ok++;
541                         }
542                         if (cc == 0) {
543                                 yyerror("Missing ']'");
544                                 return (0);
545                         }
546                         continue;
547
548                 case '*':
549                         if (!*p)
550                                 return (1);
551                         for (s--; *s; s++)
552                                 if (smatch(s, p))
553                                         return (1);
554                         return (0);
555
556                 case '\0':
557                         return (scc == '\0');
558
559                 default:
560                         if ((c & TRIM) != scc)
561                                 return (0);
562                         continue;
563
564                 case '?':
565                         if (scc == 0)
566                                 return (0);
567                         continue;
568
569                 }
570         }
571 }
572
573 static void
574 Cat(register char *s1, register char *s2)
575 {
576         int len;
577         register char *s;
578
579         len = strlen(s1) + strlen(s2) + 1;
580         nleft -= len;
581         if (nleft <= 0 || ++eargc >= GAVSIZ)
582                 yyerror("Arguments too long");
583         eargv[eargc] = 0;
584         eargv[eargc - 1] = s = malloc(len);
585         if (s == NULL)
586                 fatal("ran out of memory\n");
587         while ((*s++ = *s1++ & TRIM))
588                 ;
589         s--;
590         while ((*s++ = *s2++ & TRIM))
591                 ;
592 }
593
594 static void
595 addpath(int c)
596 {
597
598         if (pathp >= lastpathp)
599                 yyerror("Pathname too long");
600         else {
601                 *pathp++ = c & TRIM;
602                 *pathp = '\0';
603         }
604 }
605
606 /*
607  * Expand file names beginning with `~' into the
608  * user's home directory path name. Return a pointer in buf to the
609  * part corresponding to `file'.
610  */
611 char *
612 exptilde(char buf[], register char *file, int maxlen)
613 {
614         register char *s1, *s2, *s3;
615         extern char homedir[];
616
617         if (strlen(file) >= maxlen)
618            return(NULL);
619         if (*file != '~') {
620                 strcpy(buf, file);
621                 return(buf);
622         }
623         if (*++file == '\0') {
624                 s2 = homedir;
625                 s3 = NULL;
626         } else if (*file == '/') {
627                 s2 = homedir;
628                 s3 = file;
629         } else {
630                 s3 = file;
631                 while (*s3 && *s3 != '/')
632                         s3++;
633                 if (*s3 == '/')
634                         *s3 = '\0';
635                 else
636                         s3 = NULL;
637                 if (pw == NULL || strcmp(pw->pw_name, file) != 0) {
638                         if ((pw = getpwnam(file)) == NULL) {
639                                 error("%s: unknown user name\n", file);
640                                 if (s3 != NULL)
641                                         *s3 = '/';
642                                 return(NULL);
643                         }
644                 }
645                 if (s3 != NULL)
646                         *s3 = '/';
647                 s2 = pw->pw_dir;
648         }
649         for (s1 = buf; (*s1++ = *s2++) && s1 < buf+maxlen; )
650                 ;
651         s2 = --s1;
652         if (s3 != NULL && s1 < buf+maxlen) {
653                 s2++;
654                 while ((*s1++ = *s3++) && s1 < buf+maxlen)
655                         ;
656         }
657         if (s1 == buf+maxlen)
658                 return(NULL);
659         return(s2);
660 }