MGMDB/MySQL/my_open.c
2011-10-02 20:48:43 -05:00

393 lines
10 KiB
C

/* Copyright (C) 2000 MySQL AB
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#include "mysys_priv.h"
#include "mysys_err.h"
#include <my_dir.h>
#include <errno.h>
#if defined(__WIN__)
#include <share.h>
#endif
/*
Open a file
SYNOPSIS
my_open()
FileName Fully qualified file name
Flags Read | write
MyFlags Special flags
RETURN VALUE
File descriptor
*/
File my_open(const char *FileName, int Flags, myf MyFlags)
/* Path-name of file */
/* Read | write .. */
/* Special flags */
{
File fd;
DBUG_ENTER("my_open");
DBUG_PRINT("my",("Name: '%s' Flags: %d MyFlags: %d",
FileName, Flags, MyFlags));
#if defined(__WIN__)
/*
Check that we don't try to open or create a file name that may
cause problems for us in the future (like PRN)
*/
if (check_if_legal_filename(FileName))
{
errno= EACCES;
DBUG_RETURN(my_register_filename(-1, FileName, FILE_BY_OPEN,
EE_FILENOTFOUND, MyFlags));
}
#ifndef __WIN__
if (Flags & O_SHARE)
fd = sopen((char *) FileName, (Flags & ~O_SHARE) | O_BINARY, SH_DENYNO,
MY_S_IREAD | MY_S_IWRITE);
else
fd = open((char *) FileName, Flags | O_BINARY,
MY_S_IREAD | MY_S_IWRITE);
#else
fd= my_sopen((char *) 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
fd = open((char *) FileName, Flags);
#endif
DBUG_RETURN(my_register_filename(fd, FileName, FILE_BY_OPEN,
EE_FILENOTFOUND, MyFlags));
} /* my_open */
/*
Close a file
SYNOPSIS
my_close()
fd File sescriptor
myf Special Flags
*/
int my_close(File fd, myf MyFlags)
{
int err;
DBUG_ENTER("my_close");
DBUG_PRINT("my",("fd: %d MyFlags: %d",fd, MyFlags));
pthread_mutex_lock(&THR_LOCK_open);
do
{
err= close(fd);
} while (err == -1 && errno == EINTR);
if (err)
{
DBUG_PRINT("error",("Got error %d on close",err));
my_errno=errno;
if (MyFlags & (MY_FAE | MY_WME))
my_error(EE_BADCLOSE, MYF(ME_BELL+ME_WAITTANG),my_filename(fd),errno);
}
if ((uint) fd < my_file_limit && my_file_info[fd].type != UNOPEN)
{
my_free(my_file_info[fd].name, MYF(0));
#if defined(THREAD) && !defined(HAVE_PREAD)
pthread_mutex_destroy(&my_file_info[fd].mutex);
#endif
my_file_info[fd].type = UNOPEN;
}
my_file_opened--;
pthread_mutex_unlock(&THR_LOCK_open);
DBUG_RETURN(err);
} /* my_close */
/*
Register file in my_file_info[]
SYNOPSIS
my_register_filename()
fd File number opened, -1 if error on open
FileName File name
type_file_type How file was created
error_message_number Error message number if caller got error (fd == -1)
MyFlags Flags for my_close()
RETURN
-1 error
# Filenumber
*/
File my_register_filename(File fd, const char *FileName, enum file_type
type_of_file, uint error_message_number, myf MyFlags)
{
DBUG_ENTER("my_register_filename");
if ((int) fd >= 0)
{
if ((uint) fd >= my_file_limit)
{
#if defined(THREAD) && !defined(HAVE_PREAD)
my_errno= EMFILE;
#else
thread_safe_increment(my_file_opened,&THR_LOCK_open);
DBUG_RETURN(fd); /* safeguard */
#endif
}
else
{
pthread_mutex_lock(&THR_LOCK_open);
if ((my_file_info[fd].name = (char*) my_strdup(FileName,MyFlags)))
{
my_file_opened++;
my_file_total_opened++;
my_file_info[fd].type = type_of_file;
#if defined(THREAD) && !defined(HAVE_PREAD)
pthread_mutex_init(&my_file_info[fd].mutex,MY_MUTEX_INIT_FAST);
#endif
pthread_mutex_unlock(&THR_LOCK_open);
DBUG_PRINT("exit",("fd: %d",fd));
DBUG_RETURN(fd);
}
pthread_mutex_unlock(&THR_LOCK_open);
my_errno= ENOMEM;
}
(void) my_close(fd, MyFlags);
}
else
my_errno= errno;
DBUG_PRINT("error",("Got error %d on open", my_errno));
if (MyFlags & (MY_FFNF | MY_FAE | MY_WME))
{
if (my_errno == EMFILE)
error_message_number= EE_OUT_OF_FILERESOURCES;
DBUG_PRINT("error",("print err: %d",error_message_number));
my_error(error_message_number, MYF(ME_BELL+ME_WAITTANG),
FileName, my_errno);
}
DBUG_RETURN(-1);
}
#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)) == INVALID_HANDLE_VALUE)
{
/*
* 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 */
}
if ((fh= _open_osfhandle((intptr_t)osfh,
oflag & (_O_APPEND | _O_RDONLY | _O_TEXT))) == -1)
{
_dosmaperr(GetLastError()); /* map error */
CloseHandle(osfh);
}
return fh; /* return handle */
}
#endif /* __WIN__ */
#ifdef EXTRA_DEBUG
void my_print_open_files(void)
{
if (my_file_opened | my_stream_opened)
{
uint i;
for (i= 0 ; i < my_file_limit ; i++)
{
if (my_file_info[i].type != UNOPEN)
{
fprintf(stderr, EE(EE_FILE_NOT_CLOSED), my_file_info[i].name, i);
fputc('\n', stderr);
}
}
}
}
#endif