MySQL的UDF(User Defined Function)类似于一种API, 用户根据一定的规范用C/C++(或采用C调用规范的语言)编写一组函数(UDF)，然后编译成动态链接库，通过DROP FUNCTION语句来加载和卸载UDF。UDF被加载
MySQL的UDF(User Defined Function)类似于一种API, 用户根据一定的规范用C/C++(或采用C调用规范的语言)编写一组函数(UDF)，然后编译成动态链接库，通过DROP FUNCTION语句来加载和卸载UDF。UDF被加载后可以像调用MySQL的内置函数一样来调用它，并且服务器在启动时会自动加载原来存在的UDF。复制代码 代码如下:#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;#elsetypedef 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>#endif#endif#include <mysql.h>#include <m_ctype.h>#include <m_string.h>#include <stdlib.h>#include <errno.h>#include <netdb.h>#include <unistd.h>#include<fcntl.h>#include<sys time.h="">#include<sys ioctl.h="">#include <sys types.h="">#include <netinet in.h="">#include <sys socket.h="">#include <sys wait.h="">#include<arpa inet.h="">#include<unistd.h>#include <mysql.h>#include <ctype.h>#ifdef HAVE_DLOPEN
my_bool http_post_init(UDF_INIT *initid, UDF_ARGS *args, char *message);void http_post_deinit(UDF_INIT *initid);longlong http_post(UDF_INIT *initid, UDF_ARGS *args, char *is_null,char *error);/*************************************************************************** Example of init function** Arguments:** initid Points to a structure that the init function should fill.** char *ptr; A pointer that the function can use.** message Error message**RETURN This function should return 1 if something goes wrong. In this case**************************************************************************/my_bool http_post_init(UDF_INIT *initid, UDF_ARGS *args, char *message){if (args->arg_count < 3 ){ strcpy(message,"Wrong arguments to http_post; "); return 1;}
if(args->arg_count == 4 && args->args[3]!=NULL){ int flexibleLength = strlen(args->args[3]); if(flexibleLength > 160000) { int allocLength = 200 + flexibleLength; if (!(initid->ptr=(char*) malloc(allocLength) ) ) { strcpy(message,"Couldn't allocate memory in http_post_init"); return 1; } return 0; } else { initid->ptr=NULL; }
} return 0;
}
/****************************************************************************** Deinit function. This should all resources allocated by** this function.** Arguments:** initid Return value from xxxx_init****************************************************************************/void http_post_deinit(UDF_INIT *initid){ if (initid!=NULL && initid->ptr!=NULL) { free(initid->ptr); initid->ptr = NULL; }
}
/***************************************************************************** UDF string function.** Arguments:** initid Structure filled by xxx_init** args The same structure as to xxx_init. This structure** This function should return a pointer to the result string.** Normally this is 'result' but may also be an alloced string.***************************************************************************/longlong http_post( UDF_INIT *initid, UDF_ARGS *args, char *is_null __attribute__((unused)), char *error __attribute__((unused))){ int sockfd=0; int numbytes=0; int flags=0; int cycletimes=0; char* sendBuffer=NULL;
fd_set wset; struct timeval tval; tval.tv_sec = 0; tval.tv_usec = 300000;
if(initid->ptr == NULL) { char sendArray[160000] = "\0"; sendBuffer=sendArray; } else { sendBuffer = initid->ptr; }
struct sockaddr_in serv_addr; serv_addr.sin_family = AF_INET; serv_addr.sin_port = htons(atoi(args->args[1])); serv_addr.sin_addr.s_addr = inet_addr(args->args[0]); bzero(&(serv_addr.sin_zero),8);
if(args->arg_count == 4 && (args->args[3]!=NULL) ) { int argsNum = strlen(args->args[3]); sprintf(sendBuffer,"POST /?%s HTTP/1.1\r\nContent-Length:%d\r\n\r\n%s",args->args[2],argsNum,args->args[3]); } else { sprintf(sendBuffer,"POST /?%s HTTP/1.1\r\n",args->args[2]); }
if((sockfd = socket(AF_INET,SOCK_STREAM,0)) == -1) { close(sockfd); return 2; } flags = fcntl(sockfd,F_GETFL,0); fcntl(sockfd,F_SETFL,flags|O_NONBLOCK);//设置为非阻塞 do { connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(struct sockaddr)); FD_ZERO(&wset); FD_SET(sockfd,&wset); if( select(sockfd+1, NULL, &wset, NULL,&tval) <= 0 && cycletimes==5) { close(sockfd); return 5; } numbytes = send(sockfd,sendBuffer,strlen(sendBuffer),0); if(numbytes<0) { usleep(20000); } cycletimes++; }while(numbytes<0 && cycletimes!=5); if(numbytes<0) { close(sockfd); return 4; } close(sockfd); return 0;}#endif /* HAVE_DLOPEN */</ctype.h></mysql.h></unistd.h></arpa></sys></sys></netinet></sys></sys></sys></fcntl.h></unistd.h></netdb.h></errno.h></stdlib.h></m_string.h></m_ctype.h></mysql.h></string.h></m_string.h></my_sys.h></my_global.h></string.h></stdio.h></stdlib.h>
