Fixes bug #13377. my_open() & my_create() functions changed to use

my_sopen() on win32 which allows to use FILE_SHARE_DELETE flag to 
allow deleting opened files. my_sopen() implementation is added to
support this functionality.

2 files changed, 188 insertions, 1 deletions

diff --git a/mysys/my_create.c b/mysys/my_create.c
index 5fa97a9ca78..a85417c7701 100644
--- a/mysys/my_create.c
+++ b/mysys/my_create.c
@@ -47,13 +47,16 @@ File my_create(const char *FileName, int CreateFlags, int access_flags,
 #elif defined(VMS)
   fd = open((my_string) FileName, access_flags | O_CREAT, 0,
 	    "ctx=stm","ctx=bin");
-#elif defined(MSDOS) || defined(__WIN__) || defined(__EMX__) || defined(OS2)
+#elif defined(MSDOS) || defined(__EMX__) || defined(OS2)
   if (access_flags & O_SHARE)
     fd = sopen((my_string) FileName, access_flags | O_CREAT | O_BINARY,
 	       SH_DENYNO, MY_S_IREAD | MY_S_IWRITE);
   else
     fd =  open((my_string) FileName, access_flags | O_CREAT | O_BINARY,
 	       MY_S_IREAD | MY_S_IWRITE);
+#elif defined(__WIN__)
+  fd= my_sopen((my_string) FileName, access_flags | O_CREAT | O_BINARY,
+	       SH_DENYNO, MY_S_IREAD | MY_S_IWRITE);
 #else
   fd = open(FileName, access_flags);
 #endif
diff --git a/mysys/my_open.c b/mysys/my_open.c
index 69d63c49554..baca97450b7 100644
--- a/mysys/my_open.c
+++ b/mysys/my_open.c
@@ -56,12 +56,18 @@ File my_open(const char *FileName, int Flags, myf MyFlags)
     DBUG_RETURN(my_register_filename(-1, FileName, FILE_BY_OPEN,
                                      EE_FILENOTFOUND, MyFlags));
   }
+#ifndef __WIN__
   if (Flags & O_SHARE)
     fd = sopen((my_string) FileName, (Flags & ~O_SHARE) | O_BINARY, SH_DENYNO,
 	       MY_S_IREAD | MY_S_IWRITE);
   else
     fd = open((my_string) FileName, Flags | O_BINARY,
 	      MY_S_IREAD | MY_S_IWRITE);
+#else
+  fd= my_sopen((my_string) FileName, (Flags & ~O_SHARE) | O_BINARY, SH_DENYNO,
+	       MY_S_IREAD | MY_S_IWRITE);
+#endif
+
 #elif !defined(NO_OPEN_3)
   fd = open(FileName, Flags, my_umask);	/* Normal unix */
 #else
@@ -167,3 +173,181 @@ File my_register_filename(File fd, const char *FileName, enum file_type
 	     FileName, my_errno);
   return(fd);
 }
+
+#ifdef __WIN__
+
+extern void __cdecl _dosmaperr(unsigned long);
+
+/*
+  Open a file with sharing. Similar to _sopen() from libc, but allows managing
+  share delete on win32
+
+  SYNOPSIS
+    my_sopen()
+      path    fully qualified file name
+      oflag   operation flags
+      shflag	share flag
+      pmode   permission flags
+
+  RETURN VALUE
+    File descriptor of opened file if success
+    -1 and sets errno if fails.
+*/
+
+File my_sopen(const char *path, int oflag, int shflag, int pmode)
+{
+  int  fh;                                /* handle of opened file */
+  int mask;
+  HANDLE osfh;                            /* OS handle of opened file */
+  DWORD fileaccess;                       /* OS file access (requested) */
+  DWORD fileshare;                        /* OS file sharing mode */
+  DWORD filecreate;                       /* OS method of opening/creating */
+  DWORD fileattrib;                       /* OS file attribute flags */
+  SECURITY_ATTRIBUTES SecurityAttributes;
+
+  SecurityAttributes.nLength= sizeof(SecurityAttributes);
+  SecurityAttributes.lpSecurityDescriptor= NULL;
+  SecurityAttributes.bInheritHandle= !(oflag & _O_NOINHERIT);
+
+  /*
+   * decode the access flags
+   */
+  switch (oflag & (_O_RDONLY | _O_WRONLY | _O_RDWR)) {
+    case _O_RDONLY:         /* read access */
+      fileaccess= GENERIC_READ;
+      break;
+    case _O_WRONLY:         /* write access */
+      fileaccess= GENERIC_WRITE;
+      break;
+    case _O_RDWR:           /* read and write access */
+      fileaccess= GENERIC_READ | GENERIC_WRITE;
+      break;
+    default:                /* error, bad oflag */
+      errno= EINVAL;
+      _doserrno= 0L;        /* not an OS error */
+      return -1;
+  }
+
+  /*
+   * decode sharing flags
+   */
+  switch (shflag) {
+    case _SH_DENYRW:        /* exclusive access except delete */
+      fileshare= FILE_SHARE_DELETE;
+      break;
+    case _SH_DENYWR:        /* share read and delete access */
+      fileshare= FILE_SHARE_READ | FILE_SHARE_DELETE;
+      break;
+    case _SH_DENYRD:        /* share write and delete access */
+      fileshare= FILE_SHARE_WRITE | FILE_SHARE_DELETE;
+      break;
+    case _SH_DENYNO:        /* share read, write and delete access */
+      fileshare= FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
+      break;
+    case _SH_DENYRWD:       /* exclusive access */
+      fileshare= 0L;
+      break;
+    case _SH_DENYWRD:       /* share read access */
+      fileshare= FILE_SHARE_READ;
+      break;
+    case _SH_DENYRDD:       /* share write access */
+      fileshare= FILE_SHARE_WRITE;
+      break;
+    case _SH_DENYDEL:       /* share read and write access */
+      fileshare= FILE_SHARE_READ | FILE_SHARE_WRITE;
+      break;
+    default:                /* error, bad shflag */
+      errno= EINVAL;
+      _doserrno= 0L;        /* not an OS error */
+      return -1;
+  }
+
+  /*
+   * decode open/create method flags
+   */
+  switch (oflag & (_O_CREAT | _O_EXCL | _O_TRUNC)) {
+    case 0:
+    case _O_EXCL:                   // ignore EXCL w/o CREAT
+      filecreate= OPEN_EXISTING;
+      break;
+
+    case _O_CREAT:
+      filecreate= OPEN_ALWAYS;
+      break;
+
+    case _O_CREAT | _O_EXCL:
+    case _O_CREAT | _O_TRUNC | _O_EXCL:
+      filecreate= CREATE_NEW;
+      break;
+
+    case _O_TRUNC:
+    case _O_TRUNC | _O_EXCL:        // ignore EXCL w/o CREAT
+      filecreate= TRUNCATE_EXISTING;
+      break;
+
+    case _O_CREAT | _O_TRUNC:
+      filecreate= CREATE_ALWAYS;
+      break;
+
+    default:
+      // this can't happen ... all cases are covered
+      errno= EINVAL;
+      _doserrno= 0L;
+      return -1;
+  }
+
+  /*
+   * decode file attribute flags if _O_CREAT was specified
+   */
+  fileattrib= FILE_ATTRIBUTE_NORMAL;     /* default */
+  if (oflag & _O_CREAT) 
+  {
+    _umask((mask= _umask(0)));
+    
+    if (!((pmode & ~mask) & _S_IWRITE))
+      fileattrib= FILE_ATTRIBUTE_READONLY;
+  }
+
+  /*
+   * Set temporary file (delete-on-close) attribute if requested.
+   */
+  if (oflag & _O_TEMPORARY) 
+  {
+    fileattrib|= FILE_FLAG_DELETE_ON_CLOSE;
+    fileaccess|= DELETE;
+  }
+
+  /*
+   * Set temporary file (delay-flush-to-disk) attribute if requested.
+   */
+  if (oflag & _O_SHORT_LIVED)
+    fileattrib|= FILE_ATTRIBUTE_TEMPORARY;
+
+  /*
+   * Set sequential or random access attribute if requested.
+   */
+  if (oflag & _O_SEQUENTIAL)
+    fileattrib|= FILE_FLAG_SEQUENTIAL_SCAN;
+  else if (oflag & _O_RANDOM)
+    fileattrib|= FILE_FLAG_RANDOM_ACCESS;
+
+  /*
+   * try to open/create the file
+   */
+  if ((osfh= CreateFile(path, fileaccess, fileshare, &SecurityAttributes, 
+                        filecreate, fileattrib, NULL)) == (HANDLE)0xffffffff)
+  {
+    /*
+     * OS call to open/create file failed! map the error, release
+     * the lock, and return -1. note that it's not necessary to
+     * call _free_osfhnd (it hasn't been used yet).
+     */
+    _dosmaperr(GetLastError());     /* map error */
+    return -1;                      /* return error to caller */
+  }
+
+  fh= _open_osfhandle((long)osfh, oflag & (_O_APPEND | _O_RDONLY | _O_TEXT));
+
+  return fh;                        /* return handle */
+}
+#endif /* __WIN__ */