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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 */
-
- /* Written by Sinisa Milivojevic <sinisa@mysql.com> */
-
- #include <my_global.h>
- #include <mysys_priv.h>
- #ifdef HAVE_COMPRESS
- #include <my_sys.h>
- #include <m_string.h>
- #include <zlib.h>
-
- /*
- This replaces the packet with a compressed packet
-
- SYNOPSIS
- my_compress()
- packet Data to compress. This is is replaced with the compressed data.
- len Length of data to compress at 'packet'
- complen out: 0 if packet was not compressed
-
- RETURN
- 1 error. 'len' is not changed'
- 0 ok. In this case 'len' contains the size of the compressed packet
- */
-
- my_bool my_compress(uchar *packet, size_t *len, size_t *complen)
- {
- DBUG_ENTER("my_compress");
- if (*len < MIN_COMPRESS_LENGTH)
- {
- *complen=0;
- DBUG_PRINT("note",("Packet too short: Not compressed"));
- }
- else
- {
- uchar *compbuf=my_compress_alloc(packet,len,complen);
- if (!compbuf)
- DBUG_RETURN(*complen ? 0 : 1);
- memcpy(packet,compbuf,*len);
- my_free(compbuf);
- }
- DBUG_RETURN(0);
- }
-
-
- uchar *my_compress_alloc(const uchar *packet, size_t *len, size_t *complen)
- {
- uchar *compbuf;
- uLongf tmp_complen;
- int res;
- *complen= *len * 120 / 100 + 12;
-
- if (!(compbuf= (uchar *) my_malloc(key_memory_my_compress_alloc,
- *complen, MYF(MY_WME))))
- return 0; /* Not enough memory */
-
- tmp_complen= (uint) *complen;
- res= compress((Bytef*) compbuf, &tmp_complen, (Bytef*) packet, (uLong) *len);
- *complen= tmp_complen;
-
- if (res != Z_OK)
- {
- my_free(compbuf);
- return 0;
- }
-
- if (*complen >= *len)
- {
- *complen= 0;
- my_free(compbuf);
- DBUG_PRINT("note",("Packet got longer on compression; Not compressed"));
- return 0;
- }
- /* Store length of compressed packet in *len */
- swap_variables(size_t, *len, *complen);
- return compbuf;
- }
-
-
- /*
- Uncompress packet
-
- SYNOPSIS
- my_uncompress()
- packet Compressed data. This is is replaced with the orignal data.
- len Length of compressed data
- complen Length of the packet buffer (must be enough for the original
- data)
-
- RETURN
- 1 error
- 0 ok. In this case 'complen' contains the updated size of the
- real data.
- */
-
- my_bool my_uncompress(uchar *packet, size_t len, size_t *complen)
- {
- uLongf tmp_complen;
- DBUG_ENTER("my_uncompress");
-
- if (*complen) /* If compressed */
- {
- uchar *compbuf= (uchar *) my_malloc(key_memory_my_compress_alloc,
- *complen,MYF(MY_WME));
- int error;
- if (!compbuf)
- DBUG_RETURN(1); /* Not enough memory */
-
- tmp_complen= (uint) *complen;
- error= uncompress((Bytef*) compbuf, &tmp_complen, (Bytef*) packet,
- (uLong) len);
- *complen= tmp_complen;
- if (error != Z_OK)
- { /* Probably wrong packet */
- DBUG_PRINT("error",("Can't uncompress packet, error: %d",error));
- my_free(compbuf);
- DBUG_RETURN(1);
- }
- memcpy(packet, compbuf, *complen);
- my_free(compbuf);
- }
- else
- *complen= len;
- DBUG_RETURN(0);
- }
-
- /*
- Internal representation of the frm blob is:
-
- ver 4 bytes
- orglen 4 bytes
- complen 4 bytes
- */
-
- #define BLOB_HEADER 12
-
-
- /*
- packfrm is a method used to compress the frm file for storage in a
- handler. This method was developed for the NDB handler and has been moved
- here to serve also other uses.
-
- SYNOPSIS
- packfrm()
- data Data reference to frm file data.
- len Length of frm file data
- out:pack_data Reference to the pointer to the packed frm data
- out:pack_len Length of packed frm file data
-
- NOTES
- data is replaced with compressed content
-
- RETURN VALUES
- 0 Success
- >0 Failure
- */
-
- int packfrm(uchar *data, size_t len,
- uchar **pack_data, size_t *pack_len)
- {
- int error;
- size_t org_len, comp_len, blob_len;
- uchar *blob;
- DBUG_ENTER("packfrm");
- DBUG_PRINT("enter", ("data: 0x%lx len: %lu", (long) data, (ulong) len));
-
- error= 1;
- org_len= len;
- if (my_compress((uchar*)data, &org_len, &comp_len))
- goto err;
-
- DBUG_PRINT("info", ("org_len: %lu comp_len: %lu", (ulong) org_len,
- (ulong) comp_len));
- DBUG_DUMP("compressed", data, org_len);
-
- error= 2;
- blob_len= BLOB_HEADER + org_len;
- if (!(blob= (uchar*) my_malloc(key_memory_pack_frm,
- blob_len,MYF(MY_WME))))
- goto err;
-
- /* Store compressed blob in machine independent format */
- int4store(blob, 1);
- int4store(blob+4, (uint32) len);
- int4store(blob+8, (uint32) org_len); /* compressed length */
-
- /* Copy frm data into blob, already in machine independent format */
- memcpy(blob+BLOB_HEADER, data, org_len);
-
- *pack_data= blob;
- *pack_len= blob_len;
- error= 0;
-
- DBUG_PRINT("exit", ("pack_data: 0x%lx pack_len: %lu",
- (long) *pack_data, (ulong) *pack_len));
- err:
- DBUG_RETURN(error);
-
- }
-
- /*
- unpackfrm is a method used to decompress the frm file received from a
- handler. This method was developed for the NDB handler and has been moved
- here to serve also other uses for other clustered storage engines.
-
- SYNOPSIS
- unpackfrm()
- pack_data Data reference to packed frm file data
- out:unpack_data Reference to the pointer to the unpacked frm data
- out:unpack_len Length of unpacked frm file data
-
- RETURN VALUES¨
- 0 Success
- >0 Failure
- */
-
- int unpackfrm(uchar **unpack_data, size_t *unpack_len,
- const uchar *pack_data)
- {
- uchar *data;
- size_t complen, orglen;
- ulong ver;
- DBUG_ENTER("unpackfrm");
- DBUG_PRINT("enter", ("pack_data: 0x%lx", (long) pack_data));
-
- ver= uint4korr(pack_data);
- orglen= uint4korr(pack_data+4);
- complen= uint4korr(pack_data+8);
-
- DBUG_PRINT("blob",("ver: %lu complen: %lu orglen: %lu",
- ver, (ulong) complen, (ulong) orglen));
- DBUG_DUMP("blob->data", pack_data + BLOB_HEADER, complen);
-
- if (ver != 1)
- DBUG_RETURN(1);
- if (!(data= my_malloc(key_memory_pack_frm,
- MY_MAX(orglen, complen), MYF(MY_WME))))
- DBUG_RETURN(2);
- memcpy(data, pack_data + BLOB_HEADER, complen);
-
- if (my_uncompress(data, complen, &orglen))
- {
- my_free(data);
- DBUG_RETURN(3);
- }
-
- *unpack_data= data;
- *unpack_len= orglen;
-
- DBUG_PRINT("exit", ("frmdata: 0x%lx len: %lu", (long) *unpack_data,
- (ulong) *unpack_len));
- DBUG_RETURN(0);
- }
- #endif /* HAVE_COMPRESS */
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