Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 263 insertions, 0 deletions

diff --git a/mysys/my_symlink.c b/mysys/my_symlink.c
new file mode 100644
index 00000000..323ae69a
--- /dev/null
+++ b/mysys/my_symlink.c
@@ -0,0 +1,263 @@
+/*
+   Copyright (c) 2001, 2011, Oracle and/or its affiliates
+   Copyright (c) 2010, 2017, MariaDB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+#include "mysys_priv.h"
+#include "mysys_err.h"
+#include <m_string.h>
+#include <errno.h>
+#ifdef HAVE_REALPATH
+#include <sys/param.h>
+#include <sys/stat.h>
+#endif
+
+static int always_valid(const char *filename __attribute__((unused)))
+{
+  return 0;
+}
+
+int (*mysys_test_invalid_symlink)(const char *filename)= always_valid;
+
+
+/*
+  Reads the content of a symbolic link
+  If the file is not a symbolic link, return the original file name in to.
+
+  RETURN
+    0  If filename was a symlink,    (to will be set to value of symlink)
+    1  If filename was a normal file (to will be set to filename)
+   -1  on error.
+*/
+
+int my_readlink(char *to, const char *filename, myf MyFlags)
+{
+#ifndef HAVE_READLINK
+  strmov(to,filename);
+  return 1;
+#else
+  int result=0;
+  int length;
+  DBUG_ENTER("my_readlink");
+
+  if ((length=readlink(filename, to, FN_REFLEN-1)) < 0)
+  {
+    /* Don't give an error if this wasn't a symlink */
+    if ((my_errno=errno) == EINVAL)
+    {
+      result= 1;
+      strmov(to,filename);
+    }
+    else
+    {
+      if (MyFlags & MY_WME)
+	my_error(EE_CANT_READLINK, MYF(0), filename, errno);
+      result= -1;
+    }
+  }
+  else
+    to[length]=0;
+  DBUG_PRINT("exit" ,("result: %d", result));
+  DBUG_RETURN(result);
+#endif /* HAVE_READLINK */
+}
+
+
+/* Create a symbolic link */
+
+int my_symlink(const char *content, const char *linkname, myf MyFlags)
+{
+#ifndef HAVE_READLINK
+  return 0;
+#else
+  int result;
+  DBUG_ENTER("my_symlink");
+  DBUG_PRINT("enter",("content: %s  linkname: %s", content, linkname));
+
+  result= 0;
+  if (symlink(content, linkname))
+  {
+    result= -1;
+    my_errno=errno;
+    if (MyFlags & MY_WME)
+      my_error(EE_CANT_SYMLINK, MYF(0), linkname, content, errno);
+  }
+  else if ((MyFlags & MY_SYNC_DIR) && my_sync_dir_by_file(linkname, MyFlags))
+    result= -1;
+  DBUG_RETURN(result);
+#endif /* HAVE_READLINK */
+}
+
+#if defined(SCO)
+#define BUFF_LEN 4097
+#elif defined(MAXPATHLEN)
+#define BUFF_LEN MAXPATHLEN
+#else
+#define BUFF_LEN FN_LEN
+#endif
+
+
+int my_is_symlink(const char *filename __attribute__((unused)))
+{
+#if defined (HAVE_LSTAT) && defined (S_ISLNK)
+  struct stat stat_buff;
+  return !lstat(filename, &stat_buff) && S_ISLNK(stat_buff.st_mode);
+#elif defined (_WIN32)
+  DWORD dwAttr = GetFileAttributes(filename);
+  return (dwAttr != INVALID_FILE_ATTRIBUTES) &&
+    (dwAttr & FILE_ATTRIBUTE_REPARSE_POINT);
+#else  /* No symlinks */
+  return 0;
+#endif
+}
+
+/*
+  Resolve all symbolic links in path
+  'to' may be equal to 'filename'
+
+  to is guaranteed to never set to a string longer than FN_REFLEN
+  (including the end \0)
+
+  On error returns -1, unless error is file not found, in which case it
+  is 1.
+
+  Sets my_errno to specific error number.
+*/
+
+int my_realpath(char *to, const char *filename, myf MyFlags)
+{
+#if defined(HAVE_REALPATH) && !defined(HAVE_BROKEN_REALPATH)
+  int result=0;
+  char buff[BUFF_LEN];
+  char *ptr;
+  DBUG_ENTER("my_realpath");
+
+  DBUG_PRINT("info",("executing realpath"));
+  if ((ptr=realpath(filename,buff)))
+    strmake(to, ptr, FN_REFLEN-1);
+  else
+  {
+    /*
+      Realpath didn't work;  Use my_load_path() which is a poor substitute
+      original name but will at least be able to resolve paths that starts
+      with '.'.
+    */
+    if (MyFlags)
+      DBUG_PRINT("error",("realpath failed with errno: %d", errno));
+    my_errno=errno;
+    if (MyFlags & MY_WME)
+      my_error(EE_REALPATH, MYF(0), filename, my_errno);
+    my_load_path(to, filename, NullS);
+    if (my_errno == ENOENT)
+      result= 1;
+    else
+      result= -1;
+  }
+  DBUG_RETURN(result);
+#elif defined(_WIN32)
+  int ret= GetFullPathName(filename,FN_REFLEN, to, NULL);
+  if (ret == 0 || ret > FN_REFLEN)
+  {
+    my_errno= (ret > FN_REFLEN) ? ENAMETOOLONG : GetLastError();
+    if (MyFlags & MY_WME)
+      my_error(EE_REALPATH, MYF(0), filename, my_errno);
+    /* 
+      GetFullPathName didn't work : use my_load_path() which is a poor 
+      substitute original name but will at least be able to resolve 
+      paths that starts with '.'.
+    */  
+    my_load_path(to, filename, NullS);
+    return -1;
+  }
+#else
+  my_load_path(to, filename, NullS);
+#endif
+  return 0;
+}
+
+#ifdef HAVE_OPEN_PARENT_DIR_NOSYMLINKS
+/** opens the parent dir. walks the path, and does not resolve symlinks
+
+   returns the pointer to the file name (basename) within the pathname
+   or NULL in case of an error
+
+   stores the parent dir (dirname) file descriptor in pdfd.
+   It can be -1 even if there was no error!
+
+   This is used for symlinked tables for DATA/INDEX DIRECTORY.
+   The paths there have been realpath()-ed. So, we can assume here that
+
+    * `pathname` is an absolute path
+    * no '.', '..', and '//' in the path
+    * file exists
+*/
+
+const char *my_open_parent_dir_nosymlinks(const char *pathname, int *pdfd)
+{
+  char buf[FN_REFLEN + 1];
+  char *s= buf, *e= buf+1, *end= strnmov(buf, pathname, sizeof(buf));
+  int fd, dfd= -1;
+
+  if (*end)
+  {
+    errno= ENAMETOOLONG;
+    return NULL;
+  }
+
+  if (*s != '/') /* not an absolute path */
+  {
+    errno= ENOENT;
+    return NULL;
+  }
+
+  for (;;)
+  {
+    if (*e == '/') /* '//' in the path */
+    {
+      errno= ENOENT;
+      goto err;
+    }
+    while (*e && *e != '/')
+      e++;
+    *e= 0;
+
+    if (!memcmp(s, ".", 2) || !memcmp(s, "..", 3))
+    {
+      errno= ENOENT;
+      goto err;
+    }
+
+    if (++e >= end)
+    {
+      *pdfd= dfd;
+      return pathname + (s - buf);
+    }
+
+    fd = openat(dfd, s, O_NOFOLLOW | O_PATH | O_CLOEXEC);
+    if (fd < 0)
+      goto err;
+
+    if (dfd >= 0)
+      close(dfd);
+
+    dfd= fd;
+    s= e;
+  }
+err:
+  if (dfd >= 0)
+    close(dfd);
+  return NULL;
+}
+#endif