my_open.c
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:4k
- /* 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; either version 2 of the License, or
- (at your option) any later version.
- 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 */
- #define USES_TYPES
- #include "mysys_priv.h"
- #include "mysys_err.h"
- #include <my_dir.h>
- #include <errno.h>
- #if defined(MSDOS) || defined(__WIN__) || defined(__EMX__) || defined(OS2)
- #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(MSDOS) || defined(__WIN__) || defined(__EMX__) || defined(OS2)
- /*
- 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));
- }
- 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);
- #elif !defined(NO_OPEN_3)
- fd = open(FileName, Flags, my_umask); /* Normal unix */
- #else
- fd = open((my_string) 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);
- if ((err = close(fd)))
- {
- 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
- FileName
- type_file_type
- */
- File my_register_filename(File fd, const char *FileName, enum file_type
- type_of_file, uint error_message_number, myf MyFlags)
- {
- if ((int) fd >= 0)
- {
- if ((uint) fd >= my_file_limit)
- {
- #if defined(THREAD) && !defined(HAVE_PREAD)
- (void) my_close(fd,MyFlags);
- my_errno=EMFILE;
- if (MyFlags & (MY_FFNF | MY_FAE | MY_WME))
- my_error(EE_OUT_OF_FILERESOURCES, MYF(ME_BELL+ME_WAITTANG),
- FileName, my_errno);
- return(-1);
- #endif
- thread_safe_increment(my_file_opened,&THR_LOCK_open);
- return(fd); /* safeguard */
- }
- pthread_mutex_lock(&THR_LOCK_open);
- if ((my_file_info[fd].name = (char*) my_strdup(FileName,MyFlags)))
- {
- my_file_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));
- return(fd);
- }
- pthread_mutex_unlock(&THR_LOCK_open);
- (void) my_close(fd, MyFlags);
- my_errno=ENOMEM;
- }
- else
- my_errno=errno;
- DBUG_PRINT("error",("Got error %d on open",my_errno));
- if (MyFlags & (MY_FFNF | MY_FAE | MY_WME))
- my_error(error_message_number, MYF(ME_BELL+ME_WAITTANG),
- FileName, my_errno);
- return(fd);
- }