usr/src/cmd/sh/expand.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1995 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31 /*
  32  *      UNIX shell
  33  *
  34  */
  35
  36 #include        "defs.h"
  37 #include        <sys/types.h>
  38 #include        <sys/stat.h>
  39 #include        <dirent.h>
  40
  41
  42
  43 /*
  44  * globals (file name generation)
  45  *
  46  * "*" in params matches r.e ".*"
  47  * "?" in params matches r.e. "."
  48  * "[...]" in params matches character class
  49  * "[...a-z...]" in params matches a through z.
  50  *
  51  */
  52 static void addg(unsigned char *, unsigned char *, unsigned char *,
  53     unsigned char *);
  54 void makearg(struct argnod *);
  55
  56 int
  57 expand(unsigned char    *as, int rcnt)
  58 {
  59         int     count;
  60         DIR     *dirf;
  61         BOOL    dir = 0;
  62         unsigned char   *rescan = 0;
  63         unsigned char   *slashsav = 0;
  64         unsigned char   *s, *cs;
  65         unsigned char *s2 = 0;
  66         struct argnod   *schain = gchain;
  67         BOOL    slash;
  68         int     len;
  69         wchar_t wc;
  70
  71         if (trapnote & SIGSET)
  72                 return (0);
  73         s = cs = as;
  74         /*
  75          * check for meta chars
  76          */
  77         {
  78                 BOOL open;
  79
  80                 slash = 0;
  81                 open = 0;
  82                 do
  83                 {
  84                         if ((len = mbtowc(&wc, (char *)cs, MB_LEN_MAX)) <= 0) {
  85                                 len = 1;
  86                                 wc = (unsigned char)*cs;
  87                         }
  88
  89                         cs += len;
  90                         switch (wc) {
  91                         case 0:
  92                                 if (rcnt && slash)
  93                                         break;
  94                                 else
  95                                         return (0);
  96
  97                         case '/':
  98                                 slash++;
  99                                 open = 0;
 100                                 continue;
 101
 102                         case '[':
 103                                 open++;
 104                                 continue;
 105
 106                         case ']':
 107                                 if (open == 0)
 108                                         continue;
 109
 110                         case '?':
 111                         case '*':
 112                                 if (rcnt > slash)
 113                                         continue;
 114                                 else
 115                                         cs--;
 116                                 break;
 117
 118                         case '\\':
 119                                 cs++;
 120                         default:
 121                                 continue;
 122                         }
 123                         break;
 124                 } while (TRUE);
 125         }
 126
 127         for (;;) {
 128                 if (cs == s) {
 129                         s = (unsigned char *)nullstr;
 130                         break;
 131                 } else if (*--cs == '/') {
 132                         *cs = 0;
 133                         if (s == cs)
 134                                 s = (unsigned char *)"/";
 135                         else {
 136                                 /*
 137                                  * push trimmed copy of directory prefix
 138                                  * onto stack
 139                                  */
 140                                 s2 = cpystak(s);
 141                                 trim(s2);
 142                                 s = s2;
 143                         }
 144                         break;
 145                 }
 146         }
 147
 148         if ((dirf = opendir(*s ? (char *)s : (char *)".")) != 0)
 149                 dir++;
 150
 151         /* Let s point to original string because it will be trimmed later */
 152         if (s2)
 153                 s = as;
 154         count = 0;
 155         if (*cs == 0)
 156                 slashsav = cs++; /* remember where first slash in as is */
 157
 158         /* check for rescan */
 159         if (dir) {
 160                 unsigned char *rs;
 161                 struct dirent *e;
 162
 163                 rs = cs;
 164                 do /* find next / in as */
 165                 {
 166                         if (*rs == '/') {
 167                                 rescan = rs;
 168                                 *rs = 0;
 169                                 gchain = 0;
 170                         }
 171                 } while (*rs++);
 172
 173                 while ((e = readdir(dirf)) && (trapnote & SIGSET) == 0) {
 174                         if (e->d_name[0] == '.' && *cs != '.')
 175                                 continue;
 176
 177                         if (gmatch(e->d_name, cs)) {
 178                                 addg(s, (unsigned char *)e->d_name, rescan,
 179                                     slashsav);
 180                                 count++;
 181                         }
 182                 }
 183                 (void) closedir(dirf);
 184
 185                 if (rescan) {
 186                         struct argnod   *rchain;
 187
 188                         rchain = gchain;
 189                         gchain = schain;
 190                         if (count) {
 191                                 count = 0;
 192                                 while (rchain) {
 193                                         count += expand(rchain->argval,
 194                                                         slash + 1);
 195                                         rchain = rchain->argnxt;
 196                                 }
 197                         }
 198                         *rescan = '/';
 199                 }
 200         }
 201
 202         if (slashsav)
 203                 *slashsav = '/';
 204         return (count);
 205 }
 206
 207 static void
 208 addg(unsigned char *as1, unsigned char *as2, unsigned char *as3,
 209     unsigned char *as4)
 210 {
 211         unsigned char   *s1, *s2;
 212         int     c;
 213         int             len;
 214         wchar_t         wc;
 215
 216         s2 = locstak() + BYTESPERWORD;
 217         s1 = as1;
 218         if (as4) {
 219                 while (c = *s1++) {
 220                         if (s2 >= brkend)
 221                                 growstak(s2);
 222                         *s2++ = c;
 223                 }
 224                 /*
 225                  * Restore first slash before the first metacharacter
 226                  * if as1 is not "/"
 227                  */
 228                 if (as4 + 1 == s1) {
 229                         if (s2 >= brkend)
 230                                 growstak(s2);
 231                         *s2++ = '/';
 232                 }
 233         }
 234 /* add matched entries, plus extra \\ to escape \\'s */
 235         s1 = as2;
 236         for (;;) {
 237                 if ((len = mbtowc(&wc, (char *)s1, MB_LEN_MAX)) <= 0) {
 238                         len = 1;
 239                         wc = (unsigned char)*s1;
 240                 }
 241                 if (s2 >= brkend)
 242                         growstak(s2);
 243
 244                 if (wc == 0) {
 245                         *s2 = *s1++;
 246                         break;
 247                 }
 248
 249                 if (wc == '\\') {
 250                         *s2++ = '\\';
 251                         if (s2 >= brkend)
 252                                 growstak(s2);
 253                         *s2++ = '\\';
 254                         s1++;
 255                         continue;
 256                 }
 257                 if ((s2 + len) >= brkend)
 258                         growstak(s2 + len);
 259                 memcpy(s2, s1, len);
 260                 s2 += len;
 261                 s1 += len;
 262         }
 263         if (s1 = as3) {
 264                 if (s2 >= brkend)
 265                         growstak(s2);
 266                 *s2++ = '/';
 267                 do
 268                 {
 269                         if (s2 >= brkend)
 270                                 growstak(s2);
 271                 }
 272                 while (*s2++ = *++s1);
 273         }
 274         makearg((struct argnod *)endstak(s2));
 275 }
 276
 277 void
 278 makearg(struct argnod *args)
 279 {
 280         args->argnxt = gchain;
 281         gchain = args;
 282 }