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mariadb/sql/udf_example.c
Davi Arnaut 0eb26fdfa8 Bug#53445: Build with -Wall and fix warnings that it generates 
Apart strict-aliasing warnings, fix the remaining warnings
generated by GCC 4.4.4 -Wall and -Wextra flags.

One major source of warnings was the in-house function my_bcmp
which (unconventionally) took pointers to unsigned characters
as the byte sequences to be compared. Since my_bcmp and bcmp
are deprecated functions whose only difference with memcmp is
the return value, every use of the function is replaced with
memcmp as the special return value wasn't actually being used
by any caller.

There were also various other warnings, mostly due to type
mismatches, missing return values, missing prototypes, dead
code (unreachable) and ignored return values.

BUILD/SETUP.sh:
  Remove flags that are implied by -Wall and -Wextra.
  Do not warn about unused parameters in C++.
BUILD/check-cpu:
  Print only the compiler version instead of verbose banner.
  Although the option is gcc specific, the check was only
  being used for GCC specific checks anyway.
client/mysql.cc:
  bcmp is no longer defined.
client/mysqltest.cc:
  Pass a string to function expecting a format string.
  Replace use of bcmp with memcmp.
cmd-line-utils/readline/Makefile.am:
  Always define _GNU_SOURCE when compiling GNU readline.
  Required to make certain prototypes visible.
cmd-line-utils/readline/input.c:
  Condition for the code to be meaningful.
configure.in:
  Remove check for bcmp.
extra/comp_err.c:
  Use appropriate type.
extra/replace.c:
  Replace use of bcmp with memcmp.
extra/yassl/src/crypto_wrapper.cpp:
  Do not ignore the return value of fgets. Retrieve the file
  position if fgets succeed -- if it fails, the function will
  bail out and return a error.
extra/yassl/taocrypt/include/blowfish.hpp:
  Use a single array instead of accessing positions of the sbox_
  through a subscript to pbox_.
extra/yassl/taocrypt/include/runtime.hpp:
  One definition of such functions is enough.
extra/yassl/taocrypt/src/aes.cpp:
  Avoid potentially ambiguous conditions.
extra/yassl/taocrypt/src/algebra.cpp:
  Rename arguments to avoid shadowing related warnings.
extra/yassl/taocrypt/src/blowfish.cpp:
  Avoid potentially ambiguous conditions.
extra/yassl/taocrypt/src/integer.cpp:
  Do not define type within a anonymous union.
  Use a variable to return a value instead of
  leaving the result in a register -- compiler
  does not know the logic inside the asm.
extra/yassl/taocrypt/src/misc.cpp:
  Define handler for pure virtual functions.
  Remove unused code.
extra/yassl/taocrypt/src/twofish.cpp:
  Avoid potentially ambiguous conditions.
extra/yassl/testsuite/test.hpp:
  Function must have C language linkage.
include/m_string.h:
  Remove check which relied on bcmp being defined -- they weren't
  being used as bcmp is only visible when _BSD_SOURCE is defined.
include/my_bitmap.h:
  Remove bogus helpers which were used only in a few files and
  were causing warnings about dead code.
include/my_global.h:
  Due to G++ bug, always silence false-positive uninitialized
  variables warnings when compiling C++ code with G++.
  Remove bogus helper.
libmysql/Makefile.shared:
  Remove built-in implementation of bcmp.
mysql-test/lib/My/SafeProcess/safe_process.cc:
  Cast pid to largest possible type for a process identifier.
mysys/mf_loadpath.c:
  Leave space of the ending nul.
mysys/mf_pack.c:
  Replace bcmp with memcmp.
mysys/my_bitmap.c:
  Dead code removal.
mysys/my_gethwaddr.c:
  Remove unused variable.
mysys/my_getopt.c:
  Silence bogus uninitialized variable warning.
  Do not cast away the constant qualifier.
mysys/safemalloc.c:
  Cast to expected type.
mysys/thr_lock.c:
  Silence bogus uninitialized variable warning.
sql/field.cc:
  Replace bogus helper with a more appropriate logic which is
  used throughout the code.
sql/item.cc:
  Remove bogus logical condition which always evaluates to TRUE.
sql/item_create.cc:
  Simplify code to avoid signedness related warnings.
sql/log_event.cc:
  Replace use of bcmp with memcmp.
  No need to use helpers for simple bit operations.
sql/log_event_old.cc:
  Replace bmove_align with memcpy.
sql/mysqld.cc:
  Move use declaration of variable to the ifdef block where it
  is used. Remove now-unnecessary casts and arguments.
sql/set_var.cc:
  Replace bogus helpers with simple and classic bit operations.
sql/slave.cc:
  Cast to expected type and silence bogus warning.
sql/sql_class.h:
  Don't use enum values as bit flags, the supposed type safety is
  bogus as the combined bit flags are not a value in the enumeration.
sql/udf_example.c:
  Only declare variable when necessary.
sql/unireg.h:
  Replace use of bmove_align with memcpy.
storage/innobase/os/os0file.c:
  Silence bogus warning.
storage/myisam/mi_open.c:
  Remove bogus cast, DBUG_DUMP expects a pointer to unsigned
  char.
storage/myisam/mi_page.c:
  Remove bogus cast, DBUG_DUMP expects a pointer to unsigned
  char.
strings/bcmp.c:
  Remove built-in bcmp.
strings/ctype-ucs2.c:
  Silence bogus warning.
tests/mysql_client_test.c:
  Use a appropriate type as expected by simple_command().
2010-07-02 15:30:47 -03:00

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/* Copyright (C) 2002 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 */
/*
** example file of UDF (user definable functions) that are dynamicly loaded
** into the standard mysqld core.
**
** The functions name, type and shared library is saved in the new system
** table 'func'. To be able to create new functions one must have write
** privilege for the database 'mysql'. If one starts MySQL with
** --skip-grant, then UDF initialization will also be skipped.
**
** Syntax for the new commands are:
** create function <function_name> returns {string|real|integer}
** soname <name_of_shared_library>
** drop function <function_name>
**
** Each defined function may have a xxxx_init function and a xxxx_deinit
** function. The init function should alloc memory for the function
** and tell the main function about the max length of the result
** (for string functions), number of decimals (for double functions) and
** if the result may be a null value.
**
** If a function sets the 'error' argument to 1 the function will not be
** called anymore and mysqld will return NULL for all calls to this copy
** of the function.
**
** All strings arguments to functions are given as string pointer + length
** to allow handling of binary data.
** Remember that all functions must be thread safe. This means that one is not
** allowed to alloc any global or static variables that changes!
** If one needs memory one should alloc this in the init function and free
** this on the __deinit function.
**
** Note that the init and __deinit functions are only called once per
** SQL statement while the value function may be called many times
**
** Function 'metaphon' returns a metaphon string of the string argument.
** This is something like a soundex string, but it's more tuned for English.
**
** Function 'myfunc_double' returns summary of codes of all letters
** of arguments divided by summary length of all its arguments.
**
** Function 'myfunc_int' returns summary length of all its arguments.
**
** Function 'sequence' returns an sequence starting from a certain number.
**
** Function 'myfunc_argument_name' returns name of argument.
**
** On the end is a couple of functions that converts hostnames to ip and
** vice versa.
**
** A dynamicly loadable file should be compiled shared.
** (something like: gcc -shared -o my_func.so myfunc.cc).
** You can easily get all switches right by doing:
** cd sql ; make udf_example.o
** Take the compile line that make writes, remove the '-c' near the end of
** the line and add -shared -o udf_example.so to the end of the compile line.
** The resulting library (udf_example.so) should be copied to some dir
** searched by ld. (/usr/lib ?)
** If you are using gcc, then you should be able to create the udf_example.so
** by simply doing 'make udf_example.so'.
**
** After the library is made one must notify mysqld about the new
** functions with the commands:
**
** CREATE FUNCTION metaphon RETURNS STRING SONAME "udf_example.so";
** CREATE FUNCTION myfunc_double RETURNS REAL SONAME "udf_example.so";
** CREATE FUNCTION myfunc_int RETURNS INTEGER SONAME "udf_example.so";
** CREATE FUNCTION sequence RETURNS INTEGER SONAME "udf_example.so";
** CREATE FUNCTION lookup RETURNS STRING SONAME "udf_example.so";
** CREATE FUNCTION reverse_lookup RETURNS STRING SONAME "udf_example.so";
** CREATE AGGREGATE FUNCTION avgcost RETURNS REAL SONAME "udf_example.so";
** CREATE FUNCTION myfunc_argument_name RETURNS STRING SONAME "udf_example.so";
**
** After this the functions will work exactly like native MySQL functions.
** Functions should be created only once.
**
** The functions can be deleted by:
**
** DROP FUNCTION metaphon;
** DROP FUNCTION myfunc_double;
** DROP FUNCTION myfunc_int;
** DROP FUNCTION lookup;
** DROP FUNCTION reverse_lookup;
** DROP FUNCTION avgcost;
** DROP FUNCTION myfunc_argument_name;
**
** The CREATE FUNCTION and DROP FUNCTION update the func@mysql table. All
** Active function will be reloaded on every restart of server
** (if --skip-grant-tables is not given)
**
** If you ge problems with undefined symbols when loading the shared
** library, you should verify that mysqld is compiled with the -rdynamic
** option.
**
** If you can't get AGGREGATES to work, check that you have the column
** 'type' in the mysql.func table. If not, run 'mysql_fix_privilege_tables'.
**
*/
#ifdef STANDARD
/* STANDARD is defined, don't use any mysql functions */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#ifdef __WIN__
typedef unsigned __int64 ulonglong; /* Microsofts 64 bit types */
typedef __int64 longlong;
#else
typedef unsigned long long ulonglong;
typedef long long longlong;
#endif /*__WIN__*/
#else
#include <my_global.h>
#include <my_sys.h>
#if defined(MYSQL_SERVER)
#include <m_string.h> /* To get strmov() */
#else
/* when compiled as standalone */
#include <string.h>
#define strmov(a,b) stpcpy(a,b)
#define bzero(a,b) memset(a,0,b)
#define memcpy_fixed(a,b,c) memcpy(a,b,c)
#endif
#endif
#include <mysql.h>
#include <ctype.h>
#ifdef HAVE_DLOPEN
#if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_SOLARIS_STYLE_GETHOST)
static pthread_mutex_t LOCK_hostname;
#endif
/* These must be right or mysqld will not find the symbol! */
my_bool metaphon_init(UDF_INIT *initid, UDF_ARGS *args, char *message);
void metaphon_deinit(UDF_INIT *initid);
char *metaphon(UDF_INIT *initid, UDF_ARGS *args, char *result,
unsigned long *length, char *is_null, char *error);
my_bool myfunc_double_init(UDF_INIT *, UDF_ARGS *args, char *message);
double myfunc_double(UDF_INIT *initid, UDF_ARGS *args, char *is_null,
char *error);
my_bool myfunc_int_init(UDF_INIT *initid, UDF_ARGS *args, char *message);
longlong myfunc_int(UDF_INIT *initid, UDF_ARGS *args, char *is_null,
char *error);
my_bool sequence_init(UDF_INIT *initid, UDF_ARGS *args, char *message);
void sequence_deinit(UDF_INIT *initid);
longlong sequence(UDF_INIT *initid, UDF_ARGS *args, char *is_null,
char *error);
my_bool avgcost_init( UDF_INIT* initid, UDF_ARGS* args, char* message );
void avgcost_deinit( UDF_INIT* initid );
void avgcost_reset( UDF_INIT* initid, UDF_ARGS* args, char* is_null, char *error );
void avgcost_clear( UDF_INIT* initid, char* is_null, char *error );
void avgcost_add( UDF_INIT* initid, UDF_ARGS* args, char* is_null, char *error );
double avgcost( UDF_INIT* initid, UDF_ARGS* args, char* is_null, char *error );
my_bool is_const_init(UDF_INIT *initid, UDF_ARGS *args, char *message);
char *is_const(UDF_INIT *initid, UDF_ARGS *args, char *result, unsigned long
*length, char *is_null, char *error);
/*************************************************************************
** Example of init function
** Arguments:
** initid Points to a structure that the init function should fill.
** This argument is given to all other functions.
** my_bool maybe_null 1 if function can return NULL
** Default value is 1 if any of the arguments
** is declared maybe_null.
** unsigned int decimals Number of decimals.
** Default value is max decimals in any of the
** arguments.
** unsigned int max_length Length of string result.
** The default value for integer functions is 21
** The default value for real functions is 13+
** default number of decimals.
** The default value for string functions is
** the longest string argument.
** char *ptr; A pointer that the function can use.
**
** args Points to a structure which contains:
** unsigned int arg_count Number of arguments
** enum Item_result *arg_type Types for each argument.
** Types are STRING_RESULT, REAL_RESULT
** and INT_RESULT.
** char **args Pointer to constant arguments.
** Contains 0 for not constant argument.
** unsigned long *lengths; max string length for each argument
** char *maybe_null Information of which arguments
** may be NULL
**
** message Error message that should be passed to the user on fail.
** The message buffer is MYSQL_ERRMSG_SIZE big, but one should
** try to keep the error message less than 80 bytes long!
**
** This function should return 1 if something goes wrong. In this case
** message should contain something usefull!
**************************************************************************/
#define MAXMETAPH 8
my_bool metaphon_init(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
if (args->arg_count != 1 || args->arg_type[0] != STRING_RESULT)
{
strcpy(message,"Wrong arguments to metaphon; Use the source");
return 1;
}
initid->max_length=MAXMETAPH;
return 0;
}
/****************************************************************************
** Deinit function. This should free all resources allocated by
** this function.
** Arguments:
** initid Return value from xxxx_init
****************************************************************************/
void metaphon_deinit(UDF_INIT *initid __attribute__((unused)))
{
}
/***************************************************************************
** UDF string function.
** Arguments:
** initid Structure filled by xxx_init
** args The same structure as to xxx_init. This structure
** contains values for all parameters.
** Note that the functions MUST check and convert all
** to the type it wants! Null values are represented by
** a NULL pointer
** result Possible buffer to save result. At least 255 byte long.
** length Pointer to length of the above buffer. In this the function
** should save the result length
** is_null If the result is null, one should store 1 here.
** error If something goes fatally wrong one should store 1 here.
**
** This function should return a pointer to the result string.
** Normally this is 'result' but may also be an alloced string.
***************************************************************************/
/* Character coding array */
static char codes[26] = {
1,16,4,16,9,2,4,16,9,2,0,2,2,2,1,4,0,2,4,4,1,0,0,0,8,0
/* A B C D E F G H I J K L M N O P Q R S T U V W X Y Z*/
};
/*--- Macros to access character coding array -------------*/
#define ISVOWEL(x) (codes[(x) - 'A'] & 1) /* AEIOU */
/* Following letters are not changed */
#define NOCHANGE(x) (codes[(x) - 'A'] & 2) /* FJLMNR */
/* These form diphthongs when preceding H */
#define AFFECTH(x) (codes[(x) - 'A'] & 4) /* CGPST */
/* These make C and G soft */
#define MAKESOFT(x) (codes[(x) - 'A'] & 8) /* EIY */
/* These prevent GH from becoming F */
#define NOGHTOF(x) (codes[(x) - 'A'] & 16) /* BDH */
char *metaphon(UDF_INIT *initid __attribute__((unused)),
UDF_ARGS *args, char *result, unsigned long *length,
char *is_null, char *error __attribute__((unused)))
{
const char *word=args->args[0];
const char *w_end;
char *org_result;
char *n, *n_start, *n_end; /* pointers to string */
char *metaph_end; /* pointers to end of metaph */
char ntrans[32]; /* word with uppercase letters */
int KSflag; /* state flag for X to KS */
if (!word) /* Null argument */
{
*is_null=1;
return 0;
}
w_end=word+args->lengths[0];
org_result=result;
/*--------------------------------------------------------
* Copy word to internal buffer, dropping non-alphabetic
* characters and converting to uppercase.
*-------------------------------------------------------*/
for (n = ntrans + 1, n_end = ntrans + sizeof(ntrans)-2;
word != w_end && n < n_end; word++ )
if ( isalpha ( *word ))
*n++ = toupper ( *word );
if ( n == ntrans + 1 ) /* return empty string if 0 bytes */
{
*length=0;
return result;
}
n_end = n; /* set n_end to end of string */
ntrans[0] = 'Z'; /* ntrans[0] should be a neutral char */
n[0]=n[1]=0; /* pad with nulls */
n = ntrans + 1; /* assign pointer to start */
/*------------------------------------------------------------
* check for all prefixes:
* PN KN GN AE WR WH and X at start.
*----------------------------------------------------------*/
switch ( *n ) {
case 'P':
case 'K':
case 'G':
if ( n[1] == 'N')
*n++ = 0;
break;
case 'A':
if ( n[1] == 'E')
*n++ = 0;
break;
case 'W':
if ( n[1] == 'R' )
*n++ = 0;
else
if ( *(n + 1) == 'H')
{
n[1] = *n;
*n++ = 0;
}
break;
case 'X':
*n = 'S';
break;
}
/*------------------------------------------------------------
* Now, loop step through string, stopping at end of string
* or when the computed metaph is MAXMETAPH characters long
*----------------------------------------------------------*/
KSflag = 0; /* state flag for KS translation */
for (metaph_end = result + MAXMETAPH, n_start = n;
n < n_end && result < metaph_end; n++ )
{
if ( KSflag )
{
KSflag = 0;
*result++ = *n;
}
else
{
/* drop duplicates except for CC */
if ( *( n - 1 ) == *n && *n != 'C' )
continue;
/* check for F J L M N R or first letter vowel */
if ( NOCHANGE ( *n ) ||
( n == n_start && ISVOWEL ( *n )))
*result++ = *n;
else
switch ( *n ) {
case 'B': /* check for -MB */
if ( n < n_end || *( n - 1 ) != 'M' )
*result++ = *n;
break;
case 'C': /* C = X ("sh" sound) in CH and CIA */
/* = S in CE CI and CY */
/* dropped in SCI SCE SCY */
/* else K */
if ( *( n - 1 ) != 'S' ||
!MAKESOFT ( n[1]))
{
if ( n[1] == 'I' && n[2] == 'A' )
*result++ = 'X';
else
if ( MAKESOFT ( n[1]))
*result++ = 'S';
else
if ( n[1] == 'H' )
*result++ = (( n == n_start &&
!ISVOWEL ( n[2])) ||
*( n - 1 ) == 'S' ) ?
(char)'K' : (char)'X';
else
*result++ = 'K';
}
break;
case 'D': /* J before DGE, DGI, DGY, else T */
*result++ =
( n[1] == 'G' &&
MAKESOFT ( n[2])) ?
(char)'J' : (char)'T';
break;
case 'G': /* complicated, see table in text */
if (( n[1] != 'H' || ISVOWEL ( n[2]))
&& (
n[1] != 'N' ||
(
(n + 1) < n_end &&
(
n[2] != 'E' ||
*( n + 3 ) != 'D'
)
)
)
&& (
*( n - 1 ) != 'D' ||
!MAKESOFT ( n[1])
)
)
*result++ =
( MAKESOFT ( *( n + 1 )) &&
n[2] != 'G' ) ?
(char)'J' : (char)'K';
else
if ( n[1] == 'H' &&
!NOGHTOF( *( n - 3 )) &&
*( n - 4 ) != 'H')
*result++ = 'F';
break;
case 'H': /* H if before a vowel and not after */
/* C, G, P, S, T */
if ( !AFFECTH ( *( n - 1 )) &&
( !ISVOWEL ( *( n - 1 )) ||
ISVOWEL ( n[1])))
*result++ = 'H';
break;
case 'K': /* K = K, except dropped after C */
if ( *( n - 1 ) != 'C')
*result++ = 'K';
break;
case 'P': /* PH = F, else P = P */
*result++ = *( n + 1 ) == 'H'
? (char)'F' : (char)'P';
break;
case 'Q': /* Q = K (U after Q is already gone */
*result++ = 'K';
break;
case 'S': /* SH, SIO, SIA = X ("sh" sound) */
*result++ = ( n[1] == 'H' ||
( *(n + 1) == 'I' &&
( n[2] == 'O' ||
n[2] == 'A'))) ?
(char)'X' : (char)'S';
break;
case 'T': /* TIO, TIA = X ("sh" sound) */
/* TH = 0, ("th" sound ) */
if ( *( n + 1 ) == 'I' && ( n[2] == 'O'
|| n[2] == 'A') )
*result++ = 'X';
else
if ( n[1] == 'H' )
*result++ = '0';
else
if ( *( n + 1) != 'C' || n[2] != 'H')
*result++ = 'T';
break;
case 'V': /* V = F */
*result++ = 'F';
break;
case 'W': /* only exist if a vowel follows */
case 'Y':
if ( ISVOWEL ( n[1]))
*result++ = *n;
break;
case 'X': /* X = KS, except at start */
if ( n == n_start )
*result++ = 'S';
else
{
*result++ = 'K'; /* insert K, then S */
KSflag = 1; /* this flag will cause S to be
inserted on next pass thru loop */
}
break;
case 'Z':
*result++ = 'S';
break;
}
}
}
*length= (unsigned long) (result - org_result);
return org_result;
}
/***************************************************************************
** UDF double function.
** Arguments:
** initid Structure filled by xxx_init
** args The same structure as to xxx_init. This structure
** contains values for all parameters.
** Note that the functions MUST check and convert all
** to the type it wants! Null values are represented by
** a NULL pointer
** is_null If the result is null, one should store 1 here.
** error If something goes fatally wrong one should store 1 here.
**
** This function should return the result.
***************************************************************************/
my_bool myfunc_double_init(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
uint i;
if (!args->arg_count)
{
strcpy(message,"myfunc_double must have at least one argument");
return 1;
}
/*
** As this function wants to have everything as strings, force all arguments
** to strings.
*/
for (i=0 ; i < args->arg_count; i++)
args->arg_type[i]=STRING_RESULT;
initid->maybe_null=1; /* The result may be null */
initid->decimals=2; /* We want 2 decimals in the result */
initid->max_length=6; /* 3 digits + . + 2 decimals */
return 0;
}
double myfunc_double(UDF_INIT *initid __attribute__((unused)), UDF_ARGS *args,
char *is_null, char *error __attribute__((unused)))
{
unsigned long val = 0;
unsigned long v = 0;
uint i, j;
for (i = 0; i < args->arg_count; i++)
{
if (args->args[i] == NULL)
continue;
val += args->lengths[i];
for (j=args->lengths[i] ; j-- > 0 ;)
v += args->args[i][j];
}
if (val)
return (double) v/ (double) val;
*is_null=1;
return 0.0;
}
/***************************************************************************
** UDF long long function.
** Arguments:
** initid Return value from xxxx_init
** args The same structure as to xxx_init. This structure
** contains values for all parameters.
** Note that the functions MUST check and convert all
** to the type it wants! Null values are represented by
** a NULL pointer
** is_null If the result is null, one should store 1 here.
** error If something goes fatally wrong one should store 1 here.
**
** This function should return the result as a long long
***************************************************************************/
/* This function returns the sum of all arguments */
longlong myfunc_int(UDF_INIT *initid __attribute__((unused)), UDF_ARGS *args,
char *is_null __attribute__((unused)),
char *error __attribute__((unused)))
{
longlong val = 0;
uint i;
for (i = 0; i < args->arg_count; i++)
{
if (args->args[i] == NULL)
continue;
switch (args->arg_type[i]) {
case STRING_RESULT: /* Add string lengths */
val += args->lengths[i];
break;
case INT_RESULT: /* Add numbers */
val += *((longlong*) args->args[i]);
break;
case REAL_RESULT: /* Add numers as longlong */
val += (longlong) *((double*) args->args[i]);
break;
default:
break;
}
}
return val;
}
/*
At least one of _init/_deinit is needed unless the server is started
with --allow_suspicious_udfs.
*/
my_bool myfunc_int_init(UDF_INIT *initid __attribute__((unused)),
UDF_ARGS *args __attribute__((unused)),
char *message __attribute__((unused)))
{
return 0;
}
/*
Simple example of how to get a sequences starting from the first argument
or 1 if no arguments have been given
*/
my_bool sequence_init(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
if (args->arg_count > 1)
{
strmov(message,"This function takes none or 1 argument");
return 1;
}
if (args->arg_count)
args->arg_type[0]= INT_RESULT; /* Force argument to int */
if (!(initid->ptr=(char*) malloc(sizeof(longlong))))
{
strmov(message,"Couldn't allocate memory");
return 1;
}
bzero(initid->ptr,sizeof(longlong));
/*
sequence() is a non-deterministic function : it has different value
even if called with the same arguments.
*/
initid->const_item=0;
return 0;
}
void sequence_deinit(UDF_INIT *initid)
{
if (initid->ptr)
free(initid->ptr);
}
longlong sequence(UDF_INIT *initid __attribute__((unused)), UDF_ARGS *args,
char *is_null __attribute__((unused)),
char *error __attribute__((unused)))
{
ulonglong val=0;
if (args->arg_count)
val= *((longlong*) args->args[0]);
return ++*((longlong*) initid->ptr) + val;
}
/****************************************************************************
** Some functions that handles IP and hostname conversions
** The orignal function was from Zeev Suraski.
**
** CREATE FUNCTION lookup RETURNS STRING SONAME "udf_example.so";
** CREATE FUNCTION reverse_lookup RETURNS STRING SONAME "udf_example.so";
**
****************************************************************************/
#ifdef __WIN__
#include <winsock2.h>
#else
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#endif
my_bool lookup_init(UDF_INIT *initid, UDF_ARGS *args, char *message);
void lookup_deinit(UDF_INIT *initid);
char *lookup(UDF_INIT *initid, UDF_ARGS *args, char *result,
unsigned long *length, char *null_value, char *error);
my_bool reverse_lookup_init(UDF_INIT *initid, UDF_ARGS *args, char *message);
void reverse_lookup_deinit(UDF_INIT *initid);
char *reverse_lookup(UDF_INIT *initid, UDF_ARGS *args, char *result,
unsigned long *length, char *null_value, char *error);
/****************************************************************************
** lookup IP for an hostname.
**
** This code assumes that gethostbyname_r exists and inet_ntoa() is thread
** safe (As it is in Solaris)
****************************************************************************/
my_bool lookup_init(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
if (args->arg_count != 1 || args->arg_type[0] != STRING_RESULT)
{
strmov(message,"Wrong arguments to lookup; Use the source");
return 1;
}
initid->max_length=11;
initid->maybe_null=1;
#if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_SOLARIS_STYLE_GETHOST)
(void) pthread_mutex_init(&LOCK_hostname,MY_MUTEX_INIT_SLOW);
#endif
return 0;
}
void lookup_deinit(UDF_INIT *initid __attribute__((unused)))
{
#if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_SOLARIS_STYLE_GETHOST)
(void) pthread_mutex_destroy(&LOCK_hostname);
#endif
}
char *lookup(UDF_INIT *initid __attribute__((unused)), UDF_ARGS *args,
char *result, unsigned long *res_length, char *null_value,
char *error __attribute__((unused)))
{
uint length;
char name_buff[256];
struct hostent *hostent;
#if defined(HAVE_GETHOSTBYADDR_R) && defined(HAVE_SOLARIS_STYLE_GETHOST)
int tmp_errno;
char hostname_buff[2048];
struct hostent tmp_hostent;
#endif
struct in_addr in;
if (!args->args[0] || !(length=args->lengths[0]))
{
*null_value=1;
return 0;
}
if (length >= sizeof(name_buff))
length=sizeof(name_buff)-1;
memcpy(name_buff,args->args[0],length);
name_buff[length]=0;
#if defined(HAVE_GETHOSTBYADDR_R) && defined(HAVE_SOLARIS_STYLE_GETHOST)
if (!(hostent=gethostbyname_r(name_buff,&tmp_hostent,hostname_buff,
sizeof(hostname_buff), &tmp_errno)))
{
*null_value=1;
return 0;
}
#else
VOID(pthread_mutex_lock(&LOCK_hostname));
if (!(hostent= gethostbyname((char*) name_buff)))
{
VOID(pthread_mutex_unlock(&LOCK_hostname));
*null_value= 1;
return 0;
}
VOID(pthread_mutex_unlock(&LOCK_hostname));
#endif
memcpy_fixed((char*) &in,(char*) *hostent->h_addr_list, sizeof(in.s_addr));
*res_length= (ulong) (strmov(result, inet_ntoa(in)) - result);
return result;
}
/****************************************************************************
** return hostname for an IP number.
** The functions can take as arguments a string "xxx.xxx.xxx.xxx" or
** four numbers.
****************************************************************************/
my_bool reverse_lookup_init(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
if (args->arg_count == 1)
args->arg_type[0]= STRING_RESULT;
else if (args->arg_count == 4)
args->arg_type[0]=args->arg_type[1]=args->arg_type[2]=args->arg_type[3]=
INT_RESULT;
else
{
strmov(message,
"Wrong number of arguments to reverse_lookup; Use the source");
return 1;
}
initid->max_length=32;
initid->maybe_null=1;
#if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_SOLARIS_STYLE_GETHOST)
(void) pthread_mutex_init(&LOCK_hostname,MY_MUTEX_INIT_SLOW);
#endif
return 0;
}
void reverse_lookup_deinit(UDF_INIT *initid __attribute__((unused)))
{
#if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_SOLARIS_STYLE_GETHOST)
(void) pthread_mutex_destroy(&LOCK_hostname);
#endif
}
char *reverse_lookup(UDF_INIT *initid __attribute__((unused)), UDF_ARGS *args,
char *result, unsigned long *res_length,
char *null_value, char *error __attribute__((unused)))
{
#if defined(HAVE_GETHOSTBYADDR_R) && defined(HAVE_SOLARIS_STYLE_GETHOST)
char name_buff[256];
struct hostent tmp_hostent;
int tmp_errno;
#endif
struct hostent *hp;
unsigned long taddr;
uint length;
if (args->arg_count == 4)
{
if (!args->args[0] || !args->args[1] ||!args->args[2] ||!args->args[3])
{
*null_value=1;
return 0;
}
sprintf(result,"%d.%d.%d.%d",
(int) *((longlong*) args->args[0]),
(int) *((longlong*) args->args[1]),
(int) *((longlong*) args->args[2]),
(int) *((longlong*) args->args[3]));
}
else
{ /* string argument */
if (!args->args[0]) /* Return NULL for NULL values */
{
*null_value=1;
return 0;
}
length=args->lengths[0];
if (length >= (uint) *res_length-1)
length=(uint) *res_length;
memcpy(result,args->args[0],length);
result[length]=0;
}
taddr = inet_addr(result);
if (taddr == (unsigned long) -1L)
{
*null_value=1;
return 0;
}
#if defined(HAVE_GETHOSTBYADDR_R) && defined(HAVE_SOLARIS_STYLE_GETHOST)
if (!(hp=gethostbyaddr_r((char*) &taddr,sizeof(taddr), AF_INET,
&tmp_hostent, name_buff,sizeof(name_buff),
&tmp_errno)))
{
*null_value=1;
return 0;
}
#else
VOID(pthread_mutex_lock(&LOCK_hostname));
if (!(hp= gethostbyaddr((char*) &taddr, sizeof(taddr), AF_INET)))
{
VOID(pthread_mutex_unlock(&LOCK_hostname));
*null_value= 1;
return 0;
}
VOID(pthread_mutex_unlock(&LOCK_hostname));
#endif
*res_length=(ulong) (strmov(result,hp->h_name) - result);
return result;
}
/*
** Syntax for the new aggregate commands are:
** create aggregate function <function_name> returns {string|real|integer}
** soname <name_of_shared_library>
**
** Syntax for avgcost: avgcost( t.quantity, t.price )
** with t.quantity=integer, t.price=double
** (this example is provided by Andreas F. Bobak <bobak@relog.ch>)
*/
struct avgcost_data
{
ulonglong count;
longlong totalquantity;
double totalprice;
};
/*
** Average Cost Aggregate Function.
*/
my_bool
avgcost_init( UDF_INIT* initid, UDF_ARGS* args, char* message )
{
struct avgcost_data* data;
if (args->arg_count != 2)
{
strcpy(
message,
"wrong number of arguments: AVGCOST() requires two arguments"
);
return 1;
}
if ((args->arg_type[0] != INT_RESULT) || (args->arg_type[1] != REAL_RESULT) )
{
strcpy(
message,
"wrong argument type: AVGCOST() requires an INT and a REAL"
);
return 1;
}
/*
** force arguments to double.
*/
/*args->arg_type[0] = REAL_RESULT;
args->arg_type[1] = REAL_RESULT;*/
initid->maybe_null = 0; /* The result may be null */
initid->decimals = 4; /* We want 4 decimals in the result */
initid->max_length = 20; /* 6 digits + . + 10 decimals */
if (!(data = (struct avgcost_data*) malloc(sizeof(struct avgcost_data))))
{
strmov(message,"Couldn't allocate memory");
return 1;
}
data->totalquantity = 0;
data->totalprice = 0.0;
initid->ptr = (char*)data;
return 0;
}
void
avgcost_deinit( UDF_INIT* initid )
{
free(initid->ptr);
}
/* This is only for MySQL 4.0 compability */
void
avgcost_reset(UDF_INIT* initid, UDF_ARGS* args, char* is_null, char* message)
{
avgcost_clear(initid, is_null, message);
avgcost_add(initid, args, is_null, message);
}
/* This is needed to get things to work in MySQL 4.1.1 and above */
void
avgcost_clear(UDF_INIT* initid, char* is_null __attribute__((unused)),
char* message __attribute__((unused)))
{
struct avgcost_data* data = (struct avgcost_data*)initid->ptr;
data->totalprice= 0.0;
data->totalquantity= 0;
data->count= 0;
}
void
avgcost_add(UDF_INIT* initid, UDF_ARGS* args,
char* is_null __attribute__((unused)),
char* message __attribute__((unused)))
{
if (args->args[0] && args->args[1])
{
struct avgcost_data* data = (struct avgcost_data*)initid->ptr;
longlong quantity = *((longlong*)args->args[0]);
longlong newquantity = data->totalquantity + quantity;
double price = *((double*)args->args[1]);
data->count++;
if ( ((data->totalquantity >= 0) && (quantity < 0))
|| ((data->totalquantity < 0) && (quantity > 0)) )
{
/*
** passing from + to - or from - to +
*/
if ( ((quantity < 0) && (newquantity < 0))
|| ((quantity > 0) && (newquantity > 0)) )
{
data->totalprice = price * (double)newquantity;
}
/*
** sub q if totalq > 0
** add q if totalq < 0
*/
else
{
price = data->totalprice / (double)data->totalquantity;
data->totalprice = price * (double)newquantity;
}
data->totalquantity = newquantity;
}
else
{
data->totalquantity += quantity;
data->totalprice += price * (double)quantity;
}
if (data->totalquantity == 0)
data->totalprice = 0.0;
}
}
double
avgcost( UDF_INIT* initid, UDF_ARGS* args __attribute__((unused)),
char* is_null, char* error __attribute__((unused)))
{
struct avgcost_data* data = (struct avgcost_data*)initid->ptr;
if (!data->count || !data->totalquantity)
{
*is_null = 1;
return 0.0;
}
*is_null = 0;
return data->totalprice/(double)data->totalquantity;
}
my_bool myfunc_argument_name_init(UDF_INIT *initid, UDF_ARGS *args,
char *message);
char *myfunc_argument_name(UDF_INIT *initid, UDF_ARGS *args, char *result,
unsigned long *length, char *null_value,
char *error);
my_bool myfunc_argument_name_init(UDF_INIT *initid, UDF_ARGS *args,
char *message)
{
if (args->arg_count != 1)
{
strmov(message,"myfunc_argument_name_init accepts only one argument");
return 1;
}
initid->max_length= args->attribute_lengths[0];
initid->maybe_null= 1;
initid->const_item= 1;
return 0;
}
char *myfunc_argument_name(UDF_INIT *initid __attribute__((unused)),
UDF_ARGS *args, char *result,
unsigned long *length, char *null_value,
char *error __attribute__((unused)))
{
if (!args->attributes[0])
{
null_value= 0;
return 0;
}
(*length)--; /* space for ending \0 (for debugging purposes) */
if (*length > args->attribute_lengths[0])
*length= args->attribute_lengths[0];
memcpy(result, args->attributes[0], *length);
result[*length]= 0;
return result;
}
my_bool is_const_init(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
if (args->arg_count != 1)
{
strmov(message, "IS_CONST accepts only one argument");
return 1;
}
initid->ptr= (char*)((args->args[0] != NULL) ? 1UL : 0);
return 0;
}
char * is_const(UDF_INIT *initid, UDF_ARGS *args __attribute__((unused)),
char *result, unsigned long *length,
char *is_null, char *error __attribute__((unused)))
{
if (initid->ptr != 0) {
sprintf(result, "const");
} else {
sprintf(result, "not const");
}
*is_null= 0;
*length= (uint) strlen(result);
return result;
}
my_bool check_const_len_init(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
if (args->arg_count != 1)
{
strmov(message, "CHECK_CONST_LEN accepts only one argument");
return 1;
}
if (args->args[0] == 0)
{
initid->ptr= (char*)"Not constant";
}
else if(strlen(args->args[0]) == args->lengths[0])
{
initid->ptr= (char*)"Correct length";
}
else
{
initid->ptr= (char*)"Wrong length";
}
initid->max_length = 100;
return 0;
}
char * check_const_len(UDF_INIT *initid, UDF_ARGS *args __attribute__((unused)),
char *result, unsigned long *length,
char *is_null, char *error __attribute__((unused)))
{
strmov(result, initid->ptr);
*length= (uint) strlen(result);
*is_null= 0;
return result;
}
#endif /* HAVE_DLOPEN */
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