external/bsd/nvi/dist/ex/ex_cd.c

   1 /*      $NetBSD: ex_cd.c,v 1.2 2013/11/22 15:52:05 christos Exp $ */
   2 /*-
   3  * Copyright (c) 1992, 1993, 1994
   4  *      The Regents of the University of California.  All rights reserved.
   5  * Copyright (c) 1992, 1993, 1994, 1995, 1996
   6  *      Keith Bostic.  All rights reserved.
   7  *
   8  * See the LICENSE file for redistribution information.
   9  */
  10
  11 #include "config.h"
  12
  13 #ifndef lint
  14 static const char sccsid[] = "Id: ex_cd.c,v 10.12 2001/06/25 15:19:14 skimo Exp  (Berkeley) Date: 2001/06/25 15:19:14 ";
  15 #endif /* not lint */
  16
  17 #include <sys/param.h>
  18 #include <sys/queue.h>
  19
  20 #include <bitstring.h>
  21 #include <errno.h>
  22 #include <limits.h>
  23 #include <pwd.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <unistd.h>
  28
  29 #include "../common/common.h"
  30
  31 /*
  32  * ex_cd -- :cd[!] [directory]
  33  *      Change directories.
  34  *
  35  * PUBLIC: int ex_cd __P((SCR *, EXCMD *));
  36  */
  37 int
  38 ex_cd(SCR *sp, EXCMD *cmdp)
  39 {
  40         struct passwd *pw;
  41         ARGS *ap;
  42         const char *p, *t;      /* XXX: END OF THE STACK, DON'T TRUST GETCWD. */
  43         const char *dir;
  44         char buf[MAXPATHLEN * 2];
  45         size_t dlen;
  46
  47         /*
  48          * !!!
  49          * Historic practice is that the cd isn't attempted if the file has
  50          * been modified, unless its name begins with a leading '/' or the
  51          * force flag is set.
  52          */
  53         if (F_ISSET(sp->ep, F_MODIFIED) &&
  54             !FL_ISSET(cmdp->iflags, E_C_FORCE) && sp->frp->name[0] != '/') {
  55                 msgq(sp, M_ERR,
  56     "120|File modified since last complete write; write or use ! to override");
  57                 return (1);
  58         }
  59
  60         switch (cmdp->argc) {
  61         case 0:
  62                 /* If no argument, change to the user's home directory. */
  63                 if ((dir = getenv("HOME")) == NULL) {
  64                         if ((pw = getpwuid(getuid())) == NULL ||
  65                             pw->pw_dir == NULL || pw->pw_dir[0] == '\0') {
  66                                 msgq(sp, M_ERR,
  67                            "121|Unable to find home directory location");
  68                                 return (1);
  69                         }
  70                         dir = pw->pw_dir;
  71                 }
  72                 break;
  73         case 1:
  74                 INT2CHAR(sp, cmdp->argv[0]->bp, cmdp->argv[0]->len + 1,
  75                          dir, dlen);
  76                 break;
  77         default:
  78                 abort();
  79         }
  80
  81         /*
  82          * Try the current directory first.  If this succeeds, don't display
  83          * a message, vi didn't historically, and it should be obvious to the
  84          * user where they are.
  85          */
  86         if (!chdir(dir))
  87                 return (0);
  88
  89         /*
  90          * If moving to the user's home directory, or, the path begins with
  91          * "/", "./" or "../", it's the only place we try.
  92          */
  93         if (cmdp->argc == 0 ||
  94             (ap = cmdp->argv[0])->bp[0] == '/' ||
  95             (ap->len == 1 && ap->bp[0] == '.') ||
  96             (ap->len >= 2 && ap->bp[0] == '.' && ap->bp[1] == '.' &&
  97             (ap->bp[2] == '/' || ap->bp[2] == '\0')))
  98                 goto err;
  99
 100         /* Try the O_CDPATH option values. */
 101         for (p = t = O_STR(sp, O_CDPATH);; ++p)
 102                 if (*p == '\0' || *p == ':') {
 103                         /*
 104                          * Empty strings specify ".".  The only way to get an
 105                          * empty string is a leading colon, colons in a row,
 106                          * or a trailing colon.  Or, to put it the other way,
 107                          * if the length is 1 or less, then we're dealing with
 108                          * ":XXX", "XXX::XXXX" , "XXX:", or "".  Since we've
 109                          * already tried dot, we ignore tham all.
 110                          */
 111                         if (t < p - 1) {
 112                                 (void)snprintf(buf,
 113                                     sizeof(buf), "%.*s/%s", (int)(p - t),
 114                                         t, dir);
 115                                 if (!chdir(buf)) {
 116                                         if (getcwd(buf, sizeof(buf)) != NULL)
 117                 msgq_str(sp, M_INFO, buf, "122|New current directory: %s");
 118                                         return (0);
 119                                 }
 120                         }
 121                         t = p + 1;
 122                         if (*p == '\0')
 123                                 break;
 124                 }
 125
 126 err:    msgq_str(sp, M_SYSERR, dir, "%s");
 127         return (1);
 128 }