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