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- /* Copyright (c) 2000, 2021, Oracle and/or its affiliates.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License, version 2.0,
- as published by the Free Software Foundation.
-
- This program is also distributed with certain software (including
- but not limited to OpenSSL) that is licensed under separate terms,
- as designated in a particular file or component or in included license
- documentation. The authors of MySQL hereby grant you an additional
- permission to link the program and your derivative works with the
- separately licensed software that they have included with MySQL.
-
- Without limiting anything contained in the foregoing, this file,
- which is part of C Driver for MySQL (Connector/C), is also subject to the
- Universal FOSS Exception, version 1.0, a copy of which can be found at
- http://oss.oracle.com/licenses/universal-foss-exception.
-
- 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, version 2.0, 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 02110-1301 USA */
-
- #include "mysys_priv.h"
- #include "my_sys.h"
- #include "mysys_err.h"
- #include <my_base.h>
- #include <errno.h>
- #include "my_thread_local.h"
-
- /*
- Read a chunk of bytes from a file with retry's if needed
-
- The parameters are:
- File descriptor
- Buffer to hold at least Count bytes
- Bytes to read
- Flags on what to do on error
-
- Return:
- -1 on error
- 0 if flag has bits MY_NABP or MY_FNABP set
- N number of bytes read.
- */
-
- size_t my_read(File Filedes, uchar *Buffer, size_t Count, myf MyFlags)
- {
- size_t readbytes, save_count;
- DBUG_ENTER("my_read");
- DBUG_PRINT("my",("fd: %d Buffer: %p Count: %lu MyFlags: %d",
- Filedes, Buffer, (ulong) Count, MyFlags));
- save_count= Count;
-
- for (;;)
- {
- errno= 0; /* Linux, Windows don't reset this on EOF/success */
- #ifdef _WIN32
- readbytes= my_win_read(Filedes, Buffer, Count);
- #else
- readbytes= read(Filedes, Buffer, Count);
- #endif
- DBUG_EXECUTE_IF ("simulate_file_read_error",
- {
- errno= ENOSPC;
- readbytes= (size_t) -1;
- DBUG_SET("-d,simulate_file_read_error");
- DBUG_SET("-d,simulate_my_b_fill_error");
- });
-
- if (readbytes != Count)
- {
- set_my_errno(errno);
- if (errno == 0 || (readbytes != (size_t) -1 &&
- (MyFlags & (MY_NABP | MY_FNABP))))
- set_my_errno(HA_ERR_FILE_TOO_SHORT);
- DBUG_PRINT("warning",("Read only %d bytes off %lu from %d, errno: %d",
- (int) readbytes, (ulong) Count, Filedes,
- my_errno()));
-
- if ((readbytes == 0 || (int) readbytes == -1) && errno == EINTR)
- {
- DBUG_PRINT("debug", ("my_read() was interrupted and returned %ld",
- (long) readbytes));
- continue; /* Interrupted */
- }
-
- if (MyFlags & (MY_WME | MY_FAE | MY_FNABP))
- {
- char errbuf[MYSYS_STRERROR_SIZE];
- if (readbytes == (size_t) -1)
- my_error(EE_READ, MYF(0), my_filename(Filedes),
- my_errno(), my_strerror(errbuf, sizeof(errbuf), my_errno()));
- else if (MyFlags & (MY_NABP | MY_FNABP))
- my_error(EE_EOFERR, MYF(0), my_filename(Filedes),
- my_errno(), my_strerror(errbuf, sizeof(errbuf), my_errno()));
- }
- if (readbytes == (size_t) -1 ||
- ((MyFlags & (MY_FNABP | MY_NABP)) && !(MyFlags & MY_FULL_IO)))
- DBUG_RETURN(MY_FILE_ERROR); /* Return with error */
- if (readbytes != (size_t) -1 && (MyFlags & MY_FULL_IO))
- {
- Buffer+= readbytes;
- Count-= readbytes;
- continue;
- }
- }
-
- if (MyFlags & (MY_NABP | MY_FNABP))
- readbytes= 0; /* Ok on read */
- else if (MyFlags & MY_FULL_IO)
- readbytes= save_count;
- break;
- }
- DBUG_RETURN(readbytes);
- } /* my_read */
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