stdlib/FreeBSD/realpath.c.patch

   1 --- realpath.c.orig     Fri Aug 15 19:22:17 2003
   2 +++ realpath.c  Tue Dec  9 14:36:32 2003
   3 @@ -40,8 +40,27 @@
   4  #include <stdlib.h>
   5  #include <string.h>
   6  #include <unistd.h>
   7 +#include <sys/attr.h>
   8 +#include <sys/vnode.h>
   9  #include "un-namespace.h"
  10
  11 +struct attrs {
  12 +       u_int32_t len;
  13 +       attrreference_t name;
  14 +       fsobj_type_t type;
  15 +       char buf[PATH_MAX];
  16 +};
  17 +
  18 +static struct attrlist alist = {
  19 +       ATTR_BIT_MAP_COUNT,
  20 +       0,
  21 +       ATTR_CMN_NAME | ATTR_CMN_OBJTYPE,
  22 +       0,
  23 +       0,
  24 +       0,
  25 +       0,
  26 +};
  27 +
  28  /*
  29   * char *realpath(const char *path, char resolved[PATH_MAX]);
  30   *
  31 @@ -52,11 +71,12 @@
  32  char *
  33  realpath(const char *path, char resolved[PATH_MAX])
  34  {
  35 +       struct attrs attrs;
  36         struct stat sb;
  37         char *p, *q, *s;
  38 -       size_t left_len, resolved_len;
  39 +       size_t left_len, resolved_len, save_resolved_len;
  40         unsigned symlinks;
  41 -       int serrno, slen;
  42 +       int serrno, slen, useattrs, islink;
  43         char left[PATH_MAX], next_token[PATH_MAX], symlink[PATH_MAX];
  44
  45         serrno = errno;
  46 @@ -127,6 +147,13 @@
  47                 }
  48
  49                 /*
  50 +                * Save resolved_len, so that we can later null out
  51 +                * the the appended next_token, and replace with the
  52 +                * real name (matters on case-insensitive filesystems).
  53 +                */
  54 +               save_resolved_len = resolved_len;
  55 +
  56 +               /*
  57                  * Append the next path component and lstat() it. If
  58                  * lstat() fails we still can return successfully if
  59                  * there are no more path components left.
  60 @@ -136,14 +163,22 @@
  61                         errno = ENAMETOOLONG;
  62                         return (NULL);
  63                 }
  64 -               if (lstat(resolved, &sb) != 0) {
  65 +               if (getattrlist(resolved, &alist, &attrs, sizeof(attrs), FSOPT_NOFOLLOW) == 0) {
  66 +                       useattrs = 1;
  67 +                       islink = (attrs.type == VLNK);
  68 +               } else if (errno == EOPNOTSUPP || errno == EINVAL) {
  69 +                       if ((useattrs = lstat(resolved, &sb)) == 0)
  70 +                               islink = S_ISLNK(sb.st_mode);
  71 +               } else
  72 +                       useattrs = -1;
  73 +               if (useattrs < 0) {
  74                         if (errno == ENOENT && p == NULL) {
  75                                 errno = serrno;
  76                                 return (resolved);
  77                         }
  78                         return (NULL);
  79                 }
  80 -               if (S_ISLNK(sb.st_mode)) {
  81 +               if (islink) {
  82                         if (symlinks++ > MAXSYMLINKS) {
  83                                 errno = ELOOP;
  84                                 return (NULL);
  85 @@ -184,7 +219,30 @@
  86                                 }
  87                         }
  88                         left_len = strlcpy(left, symlink, sizeof(left));
  89 +               } else if (useattrs) {
  90 +                       /*
  91 +                        * attrs already has the real name.
  92 +                        */
  93 +
  94 +                       resolved[save_resolved_len] = '\0';
  95 +                       resolved_len = strlcat(resolved, (const char *)&attrs.name + attrs.name.attr_dataoffset, PATH_MAX);
  96 +                       if (resolved_len >= PATH_MAX) {
  97 +                               errno = ENAMETOOLONG;
  98 +                               return (NULL);
  99 +                       }
 100                 }
 101 +               /*
 102 +                * For the case of useattrs == 0, we could scan the directory
 103 +                * and try to match the inode.  There are many problems with
 104 +                * this: (1) the directory may not be readable, (2) for multiple
 105 +                * hard links, we would find the first, but not necessarily
 106 +                * the one specified in the path, (3) we can't try to do
 107 +                * a case-insensitive search to match the right one in (2),
 108 +                * because the underlying filesystem may do things like
 109 +                * decompose composed characters.  For most cases, doing
 110 +                * nothing is the right thing when useattrs == 0, so we punt
 111 +                * for now.
 112 +                */
 113         }
 114
 115         /*