一下是unix网络编程中的包裹函数，同样适用与windows 编程：
Writen 和Readn 等等
/* include readn */#include "unp.h"
ssize_t /* Read "n" bytes from a descriptor. */readn(int fd, void *vptr, size_t n){ size_t nleft; ssize_t nread; char *ptr;
ptr = vptr; nleft = n; while (nleft > 0) { if ( (nread = read(fd, ptr, nleft)) < 0) { if (errno == EINTR) nread = 0; /* and call read() again */ else return(-1); } else if (nread == 0) break; /* EOF */
nleft -= nread; ptr += nread; } return(n - nleft); /* return >= 0 */}/* end readn */
ssize_tReadn(int fd, void *ptr, size_t nbytes){ ssize_t n;
if ( (n = readn(fd, ptr, nbytes)) < 0) err_sys("readn error"); return(n);}
/* include writen */#include "unp.h"
ssize_t /* Write "n" bytes to a descriptor. */writen(int fd, const void *vptr, size_t n){ size_t nleft; ssize_t nwritten; const char *ptr;
ptr = vptr; nleft = n; while (nleft > 0) { if ( (nwritten = write(fd, ptr, nleft)) <= 0) { if (errno == EINTR) nwritten = 0; /* and call write() again */ else return(-1); /* error */ }
nleft -= nwritten; ptr += nwritten; } return(n);}/* end writen */
voidWriten(int fd, void *ptr, size_t nbytes){ if (writen(fd, ptr, nbytes) != nbytes) err_sys("writen error");}
/* * Socket wrapper functions. * These could all go into separate files, so only the ones needed cause * the corresponding function to be added to the executable. If sockets * are a library (SVR4) this might make a difference (?), but if sockets * are in the kernel (BSD) it doesn't matter. * * These wrapper functions also use the same prototypes as POSIX.1g, * which might differ from many implementations (i.e., POSIX.1g specifies * the fourth argument to getsockopt() as "void *", not "char *"). * * If your system's headers are not correct [i.e., the Solaris 2.5 * <sys/socket.h> omits the "const" from the second argument to both * bind() and connect()], you'll get warnings of the form: *warning: passing arg 2 of `bind' discards `const' from pointer target type *warning: passing arg 2 of `connect' discards `const' from pointer target type */
#include "unp.h"
intAccept(int fd, struct sockaddr *sa, socklen_t *salenptr){ int n;
again: if ( (n = accept(fd, sa, salenptr)) < 0) {#ifdef EPROTO if (errno == EPROTO || errno == ECONNABORTED)#else if (errno == ECONNABORTED)#endif goto again; else err_sys("accept error"); } return(n);}
voidBind(int fd, const struct sockaddr *sa, socklen_t salen){ if (bind(fd, sa, salen) < 0) err_sys("bind error");}
voidConnect(int fd, const struct sockaddr *sa, socklen_t salen){ if (connect(fd, sa, salen) < 0) err_sys("connect error");}
voidGetpeername(int fd, struct sockaddr *sa, socklen_t *salenptr){ if (getpeername(fd, sa, salenptr) < 0) err_sys("getpeername error");}
voidGetsockname(int fd, struct sockaddr *sa, socklen_t *salenptr){ if (getsockname(fd, sa, salenptr) < 0) err_sys("getsockname error");}
voidGetsockopt(int fd, int level, int optname, void *optval, socklen_t *optlenptr){ if (getsockopt(fd, level, optname, optval, optlenptr) < 0) err_sys("getsockopt error");}
intIsfdtype(int fd, int fdtype){ int n;
if ( (n = isfdtype(fd, fdtype)) < 0) err_sys("isfdtype error"); return(n);}
/* include Listen */voidListen(int fd, int backlog){ char *ptr;
/*4can override 2nd argument with environment variable */ if ( (ptr = getenv("LISTENQ")) != NULL) backlog = atoi(ptr);
if (listen(fd, backlog) < 0) err_sys("listen error");}/* end Listen */
#ifdef HAVE_POLLintPoll(struct pollfd *fdarray, unsigned long nfds, int timeout){ int n;
if ( (n = poll(fdarray, nfds, timeout)) < 0) err_sys("poll error");
return(n);}#endif
ssize_tRecv(int fd, void *ptr, size_t nbytes, int flags){ ssize_t n;
if ( (n = recv(fd, ptr, nbytes, flags)) < 0) err_sys("recv error"); return(n);}
ssize_tRecvfrom(int fd, void *ptr, size_t nbytes, int flags, struct sockaddr *sa, socklen_t *salenptr){ ssize_t n;
if ( (n = recvfrom(fd, ptr, nbytes, flags, sa, salenptr)) < 0) err_sys("recvfrom error"); return(n);}
ssize_tRecvmsg(int fd, struct msghdr *msg, int flags){ ssize_t n;
if ( (n = recvmsg(fd, msg, flags)) < 0) err_sys("recvmsg error"); return(n);}
intSelect(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout){ int n;
if ( (n = select(nfds, readfds, writefds, exceptfds, timeout)) < 0) err_sys("select error"); return(n); /* can return 0 on timeout */}
voidSend(int fd, const void *ptr, size_t nbytes, int flags){ if (send(fd, ptr, nbytes, flags) != nbytes) err_sys("send error");}
voidSendto(int fd, const void *ptr, size_t nbytes, int flags, const struct sockaddr *sa, socklen_t salen){ if (sendto(fd, ptr, nbytes, flags, sa, salen) != nbytes) err_sys("sendto error");}
voidSendmsg(int fd, const struct msghdr *msg, int flags){ int i; ssize_t nbytes;
nbytes = 0; /* must first figure out what return value should be */ for (i = 0; i < msg->msg_iovlen; i++) nbytes += msg->msg_iov[i].iov_len;
if (sendmsg(fd, msg, flags) != nbytes) err_sys("sendmsg error");}
voidSetsockopt(int fd, int level, int optname, const void *optval, socklen_t optlen){ if (setsockopt(fd, level, optname, optval, optlen) < 0) err_sys("setsockopt error");}
voidShutdown(int fd, int how){ if (shutdown(fd, how) < 0) err_sys("shutdown error");}
intSockatmark(int fd){ int n;
if ( (n = sockatmark(fd)) < 0) err_sys("sockatmark error"); return(n);}
/* include Socket */intSocket(int family, int type, int protocol){ int n;
if ( (n = socket(family, type, protocol)) < 0) err_sys("socket error"); return(n);}/* end Socket */
voidSocketpair(int family, int type, int protocol, int *fd){ int n;
if ( (n = socketpair(family, type, protocol, fd)) < 0) err_sys("socketpair error");}
/*
unp,h
*/
/* include unph *//* Our own header. Tabs are set for 4 spaces, not 8 */
#ifndef __unp_h#define __unp_h
#include "../config.h" /* configuration options for current OS */ /* "../config.h" is generated by configure */
/* If anything changes in the following list of #includes, must change acsite.m4 also, for configure's tests. */
#include <sys/types.h> /* basic system data types */#include <sys/socket.h> /* basic socket definitions */#include <sys/time.h> /* timeval{} for select() */#include <time.h> /* timespec{} for pselect() */#include <netinet/in.h> /* sockaddr_in{} and other Internet defns */#include <arpa/inet.h> /* inet(3) functions */#include <errno.h>#include <fcntl.h> /* for nonblocking */#include <netdb.h>#include <signal.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <sys/stat.h> /* for S_xxx file mode constants */#include <sys/uio.h> /* for iovec{} and readv/writev */#include <unistd.h>#include <sys/wait.h>#include <sys/un.h> /* for Unix domain sockets */
#ifdef HAVE_SYS_SELECT_H# include <sys/select.h> /* for convenience */#endif
#ifdef HAVE_POLL_H# include <poll.h> /* for convenience */#endif
#ifdef HAVE_STRINGS_H# include <strings.h> /* for convenience */#endif
/* Three headers are normally needed for socket/file ioctl's: * <sys/ioctl.h>, <sys/filio.h>, and <sys/sockio.h>. */#ifdef HAVE_SYS_IOCTL_H# include <sys/ioctl.h>#endif#ifdef HAVE_SYS_FILIO_H# include <sys/filio.h>#endif#ifdef HAVE_SYS_SOCKIO_H# include <sys/sockio.h>#endif
#ifdef HAVE_PTHREAD_H# include <pthread.h>#endif
/* OSF/1 actually disables recv() and send() in <sys/socket.h> */#ifdef __osf__#undef recv#undef send#define recv(a,b,c,d) recvfrom(a,b,c,d,0,0)#define send(a,b,c,d) sendto(a,b,c,d,0,0)#endif
#ifndef INADDR_NONE/* $$.Ic INADDR_NONE$$ */#define INADDR_NONE 0xffffffff /* should have been in <netinet/in.h> */#endif
#ifndef SHUT_RD /* these three Posix.1g names are quite new */#define SHUT_RD 0 /* shutdown for reading */#define SHUT_WR 1 /* shutdown for writing */#define SHUT_RDWR 2 /* shutdown for reading and writing *//* $$.Ic SHUT_RD$$ *//* $$.Ic SHUT_WR$$ *//* $$.Ic SHUT_RDWR$$ */#endif
/* *INDENT-OFF* */#ifndef INET_ADDRSTRLEN/* $$.Ic INET_ADDRSTRLEN$$ */#define INET_ADDRSTRLEN 16 /* "ddd.ddd.ddd.ddd/0" 1234567890123456 */#endif
/* Define following even if IPv6 not supported, so we can always allocate an adequately-sized buffer, without #ifdefs in the code. */#ifndef INET6_ADDRSTRLEN/* $$.Ic INET6_ADDRSTRLEN$$ */#define INET6_ADDRSTRLEN 46 /* max size of IPv6 address string: "xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx" or "xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:ddd.ddd.ddd.ddd/0" 1234567890123456789012345678901234567890123456 */#endif/* *INDENT-ON* */
/* Define bzero() as a macro if it's not in standard C library. */#ifndef HAVE_BZERO#define bzero(ptr,n) memset(ptr, 0, n)/* $$.If bzero$$ *//* $$.If memset$$ */#endif
/* Older resolvers do not have gethostbyname2() */#ifndef HAVE_GETHOSTBYNAME2#define gethostbyname2(host,family) gethostbyname((host))#endif
/* The structure returned by recvfrom_flags() */struct in_pktinfo { struct in_addr ipi_addr; /* dst IPv4 address */ int ipi_ifindex;/* received interface index */};/* $$.It in_pktinfo$$ *//* $$.Ib ipi_addr$$ *//* $$.Ib ipi_ifindex$$ */
/* We need the newer CMSG_LEN() and CMSG_SPACE() macros, but few implementations support them today. These two macros really need an ALIGN() macro, but each implementation does this differently. */#ifndef CMSG_LEN/* $$.Ic CMSG_LEN$$ */#define CMSG_LEN(size) (sizeof(struct cmsghdr) + (size))#endif#ifndef CMSG_SPACE/* $$.Ic CMSG_SPACE$$ */#define CMSG_SPACE(size) (sizeof(struct cmsghdr) + (size))#endif
/* Posix.1g requires the SUN_LEN() macro but not all implementations DefinE it (yet). Note that this 4.4BSD macro works regardless whether there is a length field or not. */#ifndef SUN_LEN/* $$.Im SUN_LEN$$ */# define SUN_LEN(su) / (sizeof(*(su)) - sizeof((su)->sun_path) + strlen((su)->sun_path))#endif
/* Posix.1g renames "Unix domain" as "local IPC". But not all systems DefinE AF_LOCAL and AF_LOCAL (yet). */#ifndef AF_LOCAL#define AF_LOCAL AF_UNIX#endif#ifndef PF_LOCAL#define PF_LOCAL PF_UNIX#endif
/* Posix.1g requires that an #include of <poll.h> DefinE INFTIM, but many systems still DefinE it in <sys/stropts.h>. We don't want to include all the streams stuff if it's not needed, so we just DefinE INFTIM here. This is the standard value, but there's no guarantee it is -1. */#ifndef INFTIM#define INFTIM (-1) /* infinite poll timeout *//* $$.Ic INFTIM$$ */#ifdef HAVE_POLL_H#define INFTIM_UNPH /* tell unpxti.h we defined it */#endif#endif
/* Following could be derived from SOMAXCONN in <sys/socket.h>, but many kernels still #define it as 5, while actually supporting many more */#define LISTENQ 1024 /* 2nd argument to listen() */
/* Miscellaneous constants */#define MAXLINE 4096 /* max text line length */#define MAXSOCKADDR 128 /* max socket address structure size */#define BUFFSIZE 8192 /* buffer size for reads and writes */
/* Define some port number that can be used for client-servers */#define SERV_PORT 9877 /* TCP and UDP client-servers */#define SERV_PORT_STR "9877" /* TCP and UDP client-servers */#define UNIXSTR_PATH "/tmp/unix.str" /* Unix domain stream cli-serv */#define UNIXDG_PATH "/tmp/unix.dg" /* Unix domain datagram cli-serv *//* $$.ix [LISTENQ]~constant,~definition~of$$ *//* $$.ix [MAXLINE]~constant,~definition~of$$ *//* $$.ix [MAXSOCKADDR]~constant,~definition~of$$ *//* $$.ix [BUFFSIZE]~constant,~definition~of$$ *//* $$.ix [SERV_PORT]~constant,~definition~of$$ *//* $$.ix [UNIXSTR_PATH]~constant,~definition~of$$ *//* $$.ix [UNIXDG_PATH]~constant,~definition~of$$ */
/* Following shortens all the type casts of pointer arguments */#define SA struct sockaddr
#define FILE_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) /* default file access permissions for new files */#define DIR_MODE (FILE_MODE | S_IXUSR | S_IXGRP | S_IXOTH) /* default permissions for new directories */
typedef void Sigfunc(int); /* for signal handlers */
#define min(a,b) ((a) < (b) ? (a) : (b))#define max(a,b) ((a) > (b) ? (a) : (b))
#ifndef HAVE_ADDRINFO_STRUCT# include "../lib/addrinfo.h"#endif
#ifndef HAVE_IF_NAMEINDEX_STRUCTstruct if_nameindex { unsigned int if_index; /* 1, 2, ... */ char *if_name; /* null terminated name: "le0", ... */};/* $$.It if_nameindex$$ *//* $$.Ib if_index$$ *//* $$.Ib if_name$$ */#endif
#ifndef HAVE_TIMESPEC_STRUCTstruct timespec { time_t tv_sec; /* seconds */ long tv_nsec; /* and nanoseconds */};/* $$.It timespec$$ *//* $$.Ib tv_sec$$ *//* $$.Ib tv_nsec$$ */#endif/* end unph */
/* prototypes for our own library functions */int connect_nonb(int, const SA *, socklen_t, int);int connect_timeo(int, const SA *, socklen_t, int);void daemon_init(const char *, int);void daemon_inetd(const char *, int);void dg_cli(FILE *, int, const SA *, socklen_t);void dg_echo(int, SA *, socklen_t);char *gf_time(void);void heartbeat_cli(int, int, int);void heartbeat_serv(int, int, int);struct addrinfo *host_serv(const char *, const char *, int, int);int inet_srcrt_add(char *, int);u_char *inet_srcrt_init(void);void inet_srcrt_print(u_char *, int);char **my_addrs(int *);int readable_timeo(int, int);ssize_t readline(int, void *, size_t);ssize_t readn(int, void *, size_t);ssize_t read_fd(int, void *, size_t, int *);ssize_t recvfrom_flags(int, void *, size_t, int *, SA *, socklen_t *, struct in_pktinfo *);Sigfunc *signal_intr(int, Sigfunc *);int sock_bind_wild(int, int);int sock_cmp_addr(const SA *, const SA *, socklen_t);int sock_cmp_port(const SA *, const SA *, socklen_t);int sock_get_port(const SA *, socklen_t);void sock_set_addr(SA *, socklen_t, const void *);void sock_set_port(SA *, socklen_t, int);void sock_set_wild(SA *, socklen_t);char *sock_ntop(const SA *, socklen_t);char *sock_ntop_host(const SA *, socklen_t);int sockfd_to_family(int);void str_echo(int);void str_cli(FILE *, int);int tcp_connect(const char *, const char *);int tcp_listen(const char *, const char *, socklen_t *);void tv_sub(struct timeval *, struct timeval *);int udp_client(const char *, const char *, void **, socklen_t *);int udp_connect(const char *, const char *);int udp_server(const char *, const char *, socklen_t *);int writable_timeo(int, int);ssize_t writen(int, const void *, size_t);ssize_t write_fd(int, void *, size_t, int);
#ifdef MCASTint mcast_leave(int, const SA *, socklen_t);int mcast_join(int, const SA *, socklen_t, const char *, u_int);int mcast_get_if(int);int mcast_get_loop(int);int mcast_get_ttl(int);int mcast_set_if(int, const char *, u_int);int mcast_set_loop(int, int);int mcast_set_ttl(int, int);
void Mcast_leave(int, const SA *, socklen_t);void Mcast_join(int, const SA *, socklen_t, const char *, u_int);int Mcast_get_if(int);int Mcast_get_loop(int);int Mcast_get_ttl(int);void Mcast_set_if(int, const char *, u_int);void Mcast_set_loop(int, int);void Mcast_set_ttl(int, int);#endif
unsigned short in_cksum(unsigned short *, int);
#ifndef HAVE_GETADDRINFO_PROTOint getaddrinfo(const char *, const char *, const struct addrinfo *, struct addrinfo **);void freeaddrinfo(struct addrinfo *);char *gai_strerror(int);#endif
#ifndef HAVE_GETNAMEINFO_PROTOint getnameinfo(const SA *, socklen_t, char *, size_t, char *, size_t, int);#endif
#ifndef HAVE_GETHOSTNAME_PROTOint gethostname(char *, int);#endif
#ifndef HAVE_HSTRERROR_PROTOconst char *hstrerror(int);#endif
#ifndef HAVE_IF_NAMETOINDEX_PROTOunsigned int if_nametoindex(const char *);char *if_indextoname(unsigned int, char *);void if_freenameindex(struct if_nameindex *);struct if_nameindex *if_nameindex(void);#endif
#ifndef HAVE_INET_PTON_PROTOint inet_pton(int, const char *, void *);const char *inet_ntop(int, const void *, char *, size_t);#endif
#ifndef HAVE_INET_ATON_PROTOint inet_aton(const char *, struct in_addr *);#endif
#ifndef HAVE_ISFDTYPE_PROTOint isfdtype(int, int);#endif
#ifndef HAVE_PSELECT_PROTOint pselect(int, fd_set *, fd_set *, fd_set *, const struct timespec *, const sigset_t *);#endif
#ifndef HAVE_SOCKATMARK_PROTOint sockatmark(int);#endif
#ifndef HAVE_SNPRINTF_PROTOint snprintf(char *, size_t, const char *, ...);#endif
/* prototypes for our own library wrapper functions */void Connect_timeo(int, const SA *, socklen_t, int);struct addrinfo *Host_serv(const char *, const char *, int, int);const char *Inet_ntop(int, const void *, char *, size_t);void Inet_pton(int, const char *, void *);char *If_indextoname(unsigned int, char *);unsigned int If_nametoindex(const char *);struct if_nameindex *If_nameindex(void);char **My_addrs(int *);ssize_t Read_fd(int, void *, size_t, int *);int Readable_timeo(int, int);ssize_t Recvfrom_flags(int, void *, size_t, int *, SA *, socklen_t *, struct in_pktinfo *);Sigfunc *Signal(int, Sigfunc *);Sigfunc *Signal_intr(int, Sigfunc *);int Sock_bind_wild(int, int);char *Sock_ntop(const SA *, socklen_t);char *Sock_ntop_host(const SA *, socklen_t);int Sockfd_to_family(int);int Tcp_connect(const char *, const char *);int Tcp_listen(const char *, const char *, socklen_t *);int Udp_client(const char *, const char *, void **, socklen_t *);int Udp_connect(const char *, const char *);int Udp_server(const char *, const char *, socklen_t *);ssize_t Write_fd(int, void *, size_t, int);int Writable_timeo(int, int);
/* prototypes for our Unix wrapper functions: see {Sec errors} */void *Calloc(size_t, size_t);void Close(int);void Dup2(int, int);int Fcntl(int, int, int);void Gettimeofday(struct timeval *, void *);int Ioctl(int, int, void *);pid_t Fork(void);void *Malloc(size_t);void Mktemp(char *);void *Mmap(void *, size_t, int, int, int, off_t);int Open(const char *, int, mode_t);void Pipe(int *fds);ssize_t Read(int, void *, size_t);void Sigaddset(sigset_t *, int);void Sigdelset(sigset_t *, int);void Sigemptyset(sigset_t *);void Sigfillset(sigset_t *);int Sigismember(const sigset_t *, int);void Sigpending(sigset_t *);void Sigprocmask(int, const sigset_t *, sigset_t *);char *Strdup(const char *);long Sysconf(int);void Sysctl(int *, u_int, void *, size_t *, void *, size_t);void Unlink(const char *);pid_t Wait(int *);pid_t Waitpid(pid_t, int *, int);void Write(int, void *, size_t);
/* prototypes for our stdio wrapper functions: see {Sec errors} */void Fclose(FILE *);FILE *Fdopen(int, const char *);char *Fgets(char *, int, FILE *);FILE *Fopen(const char *, const char *);void Fputs(const char *, FILE *);
/* prototypes for our socket wrapper functions: see {Sec errors} */int Accept(int, SA *, socklen_t *);void Bind(int, const SA *, socklen_t);void Connect(int, const SA *, socklen_t);void Getpeername(int, SA *, socklen_t *);void Getsockname(int, SA *, socklen_t *);void Getsockopt(int, int, int, void *, socklen_t *);int Isfdtype(int, int);void Listen(int, int);#ifdef HAVE_POLLint Poll(struct pollfd *, unsigned long, int);#endifssize_t Readline(int, void *, size_t);ssize_t Readn(int, void *, size_t);ssize_t Recv(int, void *, size_t, int);ssize_t Recvfrom(int, void *, size_t, int, SA *, socklen_t *);ssize_t Recvmsg(int, struct msghdr *, int);int Select(int, fd_set *, fd_set *, fd_set *, struct timeval *);void Send(int, const void *, size_t, int);void Sendto(int, const void *, size_t, int, const SA *, socklen_t);void Sendmsg(int, const struct msghdr *, int);void Setsockopt(int, int, int, const void *, socklen_t);void Shutdown(int, int);int Sockatmark(int);int Socket(int, int, int);void Socketpair(int, int, int, int *);void Writen(int, void *, size_t);
void err_dump(const char *, ...);void err_msg(const char *, ...);void err_quit(const char *, ...);void err_ret(const char *, ...);void err_sys(const char *, ...);
#endif /* __unp_h */
