/*
This file is a simple wrapping layer that will transparently
attach the DPF library to a program that invokes the standard
libc network functions, when statically linked.

Note that this module has no effect and will not be included
in a program unless special flags are given to the linker.
Thus, you may safely ignore this if you are not interested.

To force transparent linking, give these flags to the compiler:

-Wl,--wrap,socket -Wl,--wrap,bind -Wl,--wrap,listen -Wl,--wrap,connect
-Wl,--wrap,accept -Wl,--wrap,select -Wl,--wrap,recv -Wl,--wrap,read
-Wl,--wrap,recvfrom -Wl,--wrap,send -Wl,--wrap,sendto -Wl,--wrap,write
-Wl,--wrap,close -Wl,--wrap,dup -Wl,--wrap,dup2 -Wl,--wrap,getsockname
-Wl,--wrap,getsockaddr -Wl,--wrap,getsockopt -Wl,--wrap,fcntl
-Wl,--wrap,fork -Wl,--wrap,execve

This will only work with the GNU linker.
*/

#include "GCB.h"

static int inside=0;

#define WRAPPER( name, params, args ) \
int __real_##name params ;\
int __wrap_##name params \
{\
	if(inside) {\
		return __real_##name args ;\
	} else {\
		int result;\
		inside = 1;\
		result = DPF_##name args ;\
		inside = 0;\
		return result;\
	}\
}

WRAPPER(socket,(int domain, int type, int protocol),(domain,type,protocol))
WRAPPER(bind,(int fd, struct sockaddr *my_addr, socklen_t addrlen),(fd,my_addr,addrlen))
WRAPPER(listen,(int fd, int backlog),(fd,backlog))
WRAPPER(connect,(int fd, const struct sockaddr *serv_addr, socklen_t addrlen),(fd,serv_addr,addrlen))
WRAPPER(accept,(int fd, struct sockaddr * peer, socklen_t *addrlen),(fd,peer,addrlen))
WRAPPER(select,(int maxfd,fd_set *readfds,fd_set *writefds,fd_set *exceptfds,struct timeval *timeout),(maxfd,readfds,writefds,exceptfds,timeout))
WRAPPER(recv,(int fd, void *buf, size_t len, int flags),(fd,buf,len,flags))
WRAPPER(read,(int fd, void *buf, size_t count),(fd,buf,count))
WRAPPER(recvfrom,(int fd,  void *buf, size_t len, int flags,struct sockaddr *from, socklen_t *fromlen),(fd,buf,len,flags,from,fromlen))
WRAPPER(send,(int fd, const void *msg, size_t len, int flags),(fd,msg,len,flags))
WRAPPER(sendto,(int fd,const void *msg, size_t len, int flags,const struct sockaddr *to, socklen_t tolen),(fd,msg,len,flags,to,tolen))
WRAPPER(write,(int fd, const void *buf, size_t count),(fd,buf,count))
WRAPPER(close,(int fd),(fd))
WRAPPER(dup,(int fd),(fd))
WRAPPER(dup2,(int oldfd, int newfd),(oldfd,newfd))
WRAPPER(getsockname,(int fd, struct sockaddr * name, socklen_t *namelen),(fd,name,namelen))
WRAPPER(getsockopt,(int fd,int level,int optname,void *opt_val,socklen_t *optlen),(fd,level,optname,opt_val,optlen))
WRAPPER(fcntl,(int fd, int cmd, long arg),(fd, cmd, (void *)arg))
WRAPPER(fork,(),())
WRAPPER(execve,(const char *path, char *const argv[], char *const envp[]),(path,argv,envp))