stdlib/FreeBSD/realpath.c.patch

   1 --- realpath.c.orig     2006-09-16 19:12:28.000000000 -0700
   2 +++ realpath.c  2006-09-16 20:18:25.000000000 -0700
   3 @@ -35,13 +35,41 @@
   4  #include "namespace.h"
   5  #include <sys/param.h>
   6  #include <sys/stat.h>
   7 +#include <sys/mount.h>
   8
   9  #include <errno.h>
  10  #include <stdlib.h>
  11  #include <string.h>
  12  #include <unistd.h>
  13 +#include <sys/attr.h>
  14 +#include <sys/vnode.h>
  15  #include "un-namespace.h"
  16
  17 +struct attrs {
  18 +       u_int32_t len;
  19 +       attrreference_t name;
  20 +       dev_t dev;
  21 +       fsobj_type_t type;
  22 +       fsobj_id_t id;
  23 +       char buf[PATH_MAX];
  24 +};
  25 +
  26 +#ifndef BUILDING_VARIANT
  27 +__private_extern__ struct attrlist _rp_alist = {
  28 +       ATTR_BIT_MAP_COUNT,
  29 +       0,
  30 +       ATTR_CMN_NAME | ATTR_CMN_DEVID | ATTR_CMN_OBJTYPE | ATTR_CMN_OBJID,
  31 +       0,
  32 +       0,
  33 +       0,
  34 +       0,
  35 +};
  36 +#else /* BUILDING_VARIANT */
  37 +__private_extern__ struct attrlist _rp_alist;
  38 +#endif /* BUILDING_VARIANT */
  39 +
  40 +extern char * __private_getcwd(char *, size_t, int);
  41 +
  42  /*
  43   * char *realpath(const char *path, char resolved[PATH_MAX]);
  44   *
  45 @@ -52,24 +80,55 @@
  46  char *
  47  realpath(const char *path, char resolved[PATH_MAX])
  48  {
  49 +       struct attrs attrs;
  50         struct stat sb;
  51         char *p, *q, *s;
  52 -       size_t left_len, resolved_len;
  53 +       size_t left_len, resolved_len, save_resolved_len;
  54         unsigned symlinks;
  55 -       int serrno, slen;
  56 +       int serrno, slen, useattrs, islink;
  57         char left[PATH_MAX], next_token[PATH_MAX], symlink[PATH_MAX];
  58 +       dev_t dev, lastdev;
  59 +       struct statfs sfs;
  60 +       static dev_t rootdev;
  61 +       static int rootdev_inited = 0;
  62 +       ino_t inode;
  63
  64 +       if (path == NULL) {
  65 +               errno = EINVAL;
  66 +               return (NULL);
  67 +       }
  68 +#if __DARWIN_UNIX03
  69 +       if (*path == 0) {
  70 +               errno = ENOENT;
  71 +               return (NULL);
  72 +       }
  73 +#endif /* __DARWIN_UNIX03 */
  74 +       if (!rootdev_inited) {
  75 +               rootdev_inited = 1;
  76 +               if (stat("/", &sb) < 0) {
  77 +                       return (NULL);
  78 +                       }
  79 +               rootdev = sb.st_dev;
  80 +       }
  81         serrno = errno;
  82         symlinks = 0;
  83         if (path[0] == '/') {
  84                 resolved[0] = '/';
  85                 resolved[1] = '\0';
  86 -               if (path[1] == '\0')
  87 +               if (path[1] == '\0') {
  88                         return (resolved);
  89 +               }
  90                 resolved_len = 1;
  91                 left_len = strlcpy(left, path + 1, sizeof(left));
  92         } else {
  93 -               if (getcwd(resolved, PATH_MAX) == NULL) {
  94 +#if !defined(VARIANT_DARWINEXTSN) && __DARWIN_UNIX03
  95 +               /* 4447159: don't use GETPATH, so this will fail if */
  96 +               /* if parent directories are not readable, as per POSIX */
  97 +               if (__private_getcwd(resolved, PATH_MAX, 0) == NULL)
  98 +#else /* VARIANT_DARWINEXTSN || !__DARWIN_UNIX03 */
  99 +               if (__private_getcwd(resolved, PATH_MAX, 1) == NULL)
 100 +#endif /* !VARIANT_DARWINEXTSN && __DARWIN_UNIX03 */
 101 +               {
 102                         strlcpy(resolved, ".", PATH_MAX);
 103                         return (NULL);
 104                 }
 105 @@ -80,6 +139,13 @@
 106                 errno = ENAMETOOLONG;
 107                 return (NULL);
 108         }
 109 +       if (resolved_len > 1) {
 110 +               if (stat(resolved, &sb) < 0) {
 111 +                       return (NULL);
 112 +               }
 113 +               lastdev = sb.st_dev;
 114 +       } else
 115 +               lastdev = rootdev;
 116
 117         /*
 118          * Iterate over path components in `left'.
 119 @@ -127,6 +193,13 @@
 120                 }
 121
 122                 /*
 123 +                * Save resolved_len, so that we can later null out
 124 +                * the the appended next_token, and replace with the
 125 +                * real name (matters on case-insensitive filesystems).
 126 +                */
 127 +               save_resolved_len = resolved_len;
 128 +
 129 +               /*
 130                  * Append the next path component and lstat() it. If
 131                  * lstat() fails we still can return successfully if
 132                  * there are no more path components left.
 133 @@ -136,25 +209,87 @@
 134                         errno = ENAMETOOLONG;
 135                         return (NULL);
 136                 }
 137 -               if (lstat(resolved, &sb) != 0) {
 138 +               if (getattrlist(resolved, &_rp_alist, &attrs, sizeof(attrs), FSOPT_NOFOLLOW) == 0) {
 139 +                       useattrs = 1;
 140 +                       islink = (attrs.type == VLNK);
 141 +                       dev = attrs.dev;
 142 +                       inode = attrs.id.fid_objno;
 143 +               } else if (errno == ENOTSUP || errno == EINVAL) {
 144 +                       if ((useattrs = lstat(resolved, &sb)) == 0) {
 145 +                               islink = S_ISLNK(sb.st_mode);
 146 +                               dev = sb.st_dev;
 147 +                               inode = sb.st_ino;
 148 +                       }
 149 +               } else
 150 +                       useattrs = -1;
 151 +               if (useattrs < 0) {
 152 +#if !__DARWIN_UNIX03
 153                         if (errno == ENOENT && p == NULL) {
 154                                 errno = serrno;
 155                                 return (resolved);
 156                         }
 157 +#endif /* !__DARWIN_UNIX03 */
 158                         return (NULL);
 159                 }
 160 -               if (S_ISLNK(sb.st_mode)) {
 161 +               if (dev != lastdev) {
 162 +                       /*
 163 +                        * We have crossed a mountpoint.  For volumes like UDF
 164 +                        * the getattrlist name may not match the actual
 165 +                        * mountpoint, so we just copy the mountpoint directly.
 166 +                        * (3703138).  However, the mountpoint may not be
 167 +                        * accessible, as when chroot-ed, so check first.
 168 +                        * There may be a file on the chroot-ed volume with
 169 +                        * the same name as the mountpoint, so compare device
 170 +                        * and inode numbers.
 171 +                        */
 172 +                       lastdev = dev;
 173 +                       if (statfs(resolved, &sfs) == 0 && lstat(sfs.f_mntonname, &sb) == 0 && dev == sb.st_dev && inode == sb.st_ino) {
 174 +                               /*
 175 +                                * However, it's possible that the mountpoint
 176 +                                * path matches, even though it isn't the real
 177 +                                * path in the chroot-ed environment, so check
 178 +                                * that each component of the mountpoint
 179 +                                * is a directory (and not a symlink)
 180 +                                */
 181 +                               char temp[MNAMELEN];
 182 +                               char *cp;
 183 +                               int ok = 1;
 184 +
 185 +                               strcpy(temp, sfs.f_mntonname);
 186 +                               for(;;) {
 187 +                                       if ((cp = strrchr(temp, '/')) == NULL) {
 188 +                                               ok = 0;
 189 +                                               break;
 190 +                                       }
 191 +                                       if (cp <= temp)
 192 +                                               break;
 193 +                                       *cp = 0;
 194 +                                       if (lstat(temp, &sb) < 0 || (sb.st_mode & S_IFMT) != S_IFDIR) {
 195 +                                               ok = 0;
 196 +                                               break;
 197 +                                       }
 198 +                               }
 199 +                               if (ok) {
 200 +                                       resolved_len = strlcpy(resolved, sfs.f_mntonname, PATH_MAX);
 201 +                                       continue;
 202 +                               }
 203 +                       }
 204 +                       /* if we fail, use the other methods. */
 205 +               }
 206 +               if (islink) {
 207                         if (symlinks++ > MAXSYMLINKS) {
 208                                 errno = ELOOP;
 209                                 return (NULL);
 210                         }
 211                         slen = readlink(resolved, symlink, sizeof(symlink) - 1);
 212 -                       if (slen < 0)
 213 +                       if (slen < 0) {
 214                                 return (NULL);
 215 +                       }
 216                         symlink[slen] = '\0';
 217                         if (symlink[0] == '/') {
 218                                 resolved[1] = 0;
 219                                 resolved_len = 1;
 220 +                               lastdev = rootdev;
 221                         } else if (resolved_len > 1) {
 222                                 /* Strip the last path component. */
 223                                 resolved[resolved_len - 1] = '\0';
 224 @@ -184,7 +319,30 @@
 225                                 }
 226                         }
 227                         left_len = strlcpy(left, symlink, sizeof(left));
 228 +               } else if (useattrs) {
 229 +                       /*
 230 +                        * attrs already has the real name.
 231 +                        */
 232 +
 233 +                       resolved[save_resolved_len] = '\0';
 234 +                       resolved_len = strlcat(resolved, (const char *)&attrs.name + attrs.name.attr_dataoffset, PATH_MAX);
 235 +                       if (resolved_len >= PATH_MAX) {
 236 +                               errno = ENAMETOOLONG;
 237 +                               return (NULL);
 238 +                       }
 239                 }
 240 +               /*
 241 +                * For the case of useattrs == 0, we could scan the directory
 242 +                * and try to match the inode.  There are many problems with
 243 +                * this: (1) the directory may not be readable, (2) for multiple
 244 +                * hard links, we would find the first, but not necessarily
 245 +                * the one specified in the path, (3) we can't try to do
 246 +                * a case-insensitive search to match the right one in (2),
 247 +                * because the underlying filesystem may do things like
 248 +                * decompose composed characters.  For most cases, doing
 249 +                * nothing is the right thing when useattrs == 0, so we punt
 250 +                * for now.
 251 +                */
 252         }
 253
 254         /*