socat/xio.h

/* source: xio.h */
/* Copyright Gerhard Rieger 2001-2008 */
/* Published under the GNU General Public License V.2, see file COPYING */

#ifndef __xio_h_included
#define __xio_h_included 1

#if 1 /*!*/
#include "mytypes.h"
#include "sysutils.h"
#endif

#define XIO_MAXSOCK 2

/* Linux 2.2.10 */
#define HAVE_STRUCT_LINGER 1

#define LINETERM_RAW 0
#define LINETERM_CR 1
#define LINETERM_CRNL 2

union xioaddr_desc;
struct opt;

/* the flags argument of xioopen */
#define XIO_RDONLY  O_RDONLY /* asserted to be 0 */
#define XIO_WRONLY  O_WRONLY /* asserted to be 1 */
#define XIO_RDWR    O_RDWR   /* asserted to be 2 */
#define XIO_ACCMODE O_ACCMODE	/* must be 3 */
/* 3 is undefined */
#define XIO_MAYFORK     4 /* address is allowed to fork the program (fork),
			     especially with listen and connect addresses */
#define XIO_MAYCHILD    8 /* address is allowed to fork off a child that 
			     exec's another program or calls system() */
#define XIO_MAYEXEC    16 /* address is allowed to exec a prog (exec+nofork) */
#define XIO_MAYCONVERT 32 /* address is allowed to perform modifications on the
			     stream data, e.g. SSL, READLINE; CRLF */
#define XIO_MAYCHAIN   64 /* address is allowed to consist of a chain of
			     subaddresses that are handled by socat
			     subprocesses */
#define XIO_EMBEDDED 256	/* address is nonterminal */
#define XIO_MAYALL INT_MAX	/* all features enabled */

/* the status flags of xiofile_t */
#define XIO_DOESFORK    XIO_MAYFORK
#define XIO_DOESCHILD   XIO_MAYCHILD
#define XIO_DOESEXEC    XIO_MAYEXEC
#define XIO_DOESCONVERT XIO_MAYCONVERT
#define XIO_DOESCHAIN	XIO_MAYCHAIN

/* sometimes we use a set of allowed direction(s), a bit pattern */
#define XIOBIT_RDONLY (1<<XIO_RDONLY)
#define XIOBIT_WRONLY (1<<XIO_WRONLY)
#define XIOBIT_RDWR   (1<<XIO_RDWR)
#define XIOBIT_ALL    (XIOBIT_RDONLY|XIOBIT_WRONLY|XIOBIT_RDWR)
#define XIOBIT_ALLRD  (XIOBIT_RDONLY|XIOBIT_RDWR)
#define XIOBIT_ALLWR  (XIOBIT_WRONLY|XIOBIT_RDWR)
#define XIOBIT_ONE    (XIOBIT_RDONLY|XIOBIT_WRONLY)
/* reverse the direction pattern */
#define XIOBIT_REVERSE(x) (((x)&XIOBIT_RDWR)|(((x)&XIOBIT_RDONLY)?XIOBIT_WRONLY:0)|(((x)&XIOBIT_WRONLY)?XIOBIT_RDONLY:0))

/* methods for reading and writing, and for related checks */
#define XIODATA_READMASK	0xf000	/* mask for basic r/w method */
#define XIOREAD_STREAM		0x1000	/* read() (default) */
#define XIOREAD_RECV		0x2000	/* recvfrom() */
#define XIOREAD_PTY		0x4000	/* handle EIO */
#define XIOREAD_READLINE	0x5000	/* ... */
#define XIOREAD_OPENSSL		0x6000	/* SSL_read() */
#define XIOREAD_TEST		0x7000	/* xioread_test() */
#define XIODATA_WRITEMASK	0x0f00	/* mask for basic r/w method */
#define XIOWRITE_STREAM		0x0100	/* write() (default) */
#define XIOWRITE_SENDTO		0x0200	/* sendto() */
#define XIOWRITE_PIPE		0x0300	/* write() to alternate (pipe) Fd */
#define XIOWRITE_2PIPE		0x0400	/* write() to alternate (2pipe) Fd */
#define XIOWRITE_READLINE	0x0500	/* check for prompt */
#define XIOWRITE_OPENSSL	0x0600	/* SSL_write() */
#define XIOWRITE_TEST		0x0700	/* xiowrite_test() */
#define XIOWRITE_TESTREV	0x0800	/* xiowrite_testrev() */
/* modifiers to XIODATA_READ_RECV */
#define XIOREAD_RECV_CHECKPORT	0x0001	/* recv, check peer port */
#define XIOREAD_RECV_CHECKADDR	0x0002	/* recv, check peer address */
#define XIOREAD_RECV_CHECKRANGE	0x0004	/* recv, check if peer addr in range */
#define XIOREAD_RECV_ONESHOT	0x0008	/* give EOF after first packet */
#define XIOREAD_RECV_SKIPIP	0x0010	/* recv, skip IPv4 header */
#define XIOREAD_RECV_FROM	0x0020	/* remember peer for replying */

/* combinations */
#define XIODATA_MASK		(XIODATA_READMASK|XIODATA_WRITEMASK)
#define XIODATA_STREAM		(XIOREAD_STREAM|XIOWRITE_STREAM)
#define XIODATA_RECVFROM	(XIOREAD_RECV|XIOWRITE_SENDTO|XIOREAD_RECV_CHECKPORT|XIOREAD_RECV_CHECKADDR|XIOREAD_RECV_FROM)
#define XIODATA_RECVFROM_SKIPIP	(XIODATA_RECVFROM|XIOREAD_RECV_SKIPIP)
#define XIODATA_RECVFROM_ONE	(XIODATA_RECVFROM|XIOREAD_RECV_ONESHOT)
#define XIODATA_RECVFROM_SKIPIP_ONE	(XIODATA_RECVFROM_SKIPIP|XIOREAD_RECV_ONESHOT)
#define XIODATA_RECV		(XIOREAD_RECV|XIOWRITE_SENDTO|XIOREAD_RECV_CHECKRANGE)
#define XIODATA_RECV_SKIPIP	(XIODATA_RECV|XIOREAD_RECV_SKIPIP)
#define XIODATA_PIPE		(XIOREAD_STREAM|XIOWRITE_PIPE)
#define XIODATA_2PIPE		(XIOREAD_STREAM|XIOWRITE_2PIPE)
#define XIODATA_PTY		(XIOREAD_PTY|XIOWRITE_STREAM)
#define XIODATA_READLINE	(XIOREAD_READLINE|XIOWRITE_STREAM)
#define XIODATA_OPENSSL		(XIOREAD_OPENSSL|XIOWRITE_OPENSSL)
#define XIODATA_TEST		(XIOREAD_TEST|XIOWRITE_TEST)
#define XIODATA_TESTUNI		XIOWRITE_TEST
#define XIODATA_TESTREV		XIOWRITE_TESTREV

/* XIOSHUT_* define the actions on shutdown of the address */
/*  */
#define XIOSHUTRD_MASK		0x00f0
#define XIOSHUTWR_MASK		0x000f
#define XIOSHUTSPEC_MASK	0xff00	/* specific action */
#define XIOSHUTRD_UNSPEC	0x0000
#define XIOSHUTWR_UNSPEC	0x0000
#define XIOSHUTRD_NONE		0x0010	/* no action - e.g. stdin */
#define XIOSHUTWR_NONE		0x0001	/* no action - e.g. stdout */
#define XIOSHUTRD_CLOSE		0x0020	/* close() */
#define XIOSHUTWR_CLOSE		0x0002	/* close() */
#define XIOSHUTRD_DOWN		0x0030	/* shutdown(, SHUT_RD) */
#define XIOSHUTWR_DOWN		0x0003	/* shutdown(, SHUT_WR) */
#define XIOSHUTRD_SIGHUP	0x0040	/* kill sub process */
#define XIOSHUTWR_SIGHUP	0x0004	/* flush sub process with SIGHPUP */
#define XIOSHUTRD_SIGTERM	0x0050	/* kill sub process with SIGTERM */
#define XIOSHUTWR_SIGTERM	0x0005	/* kill sub process with SIGTERM */
#define XIOSHUTWR_SIGKILL	0x0006	/* kill sub process with SIGKILL */
#define XIOSHUT_UNSPEC		(XIOSHUTRD_UNSPEC|XIOSHUTWR_UNSPEC)
#define XIOSHUT_NONE		(XIOSHUTRD_NONE|XIOSHUTWR_NONE)
#define XIOSHUT_CLOSE		(XIOSHUTRD_CLOSE|XIOSHUTWR_CLOSE)
#define XIOSHUT_DOWN		(XIOSHUTRD_DOWN|XIOSHUTWR_DOWN)
#define XIOSHUT_KILL		(XIOSHUTRD_KILL|XIOSHUTWR_KILL)
#define XIOSHUT_OPENSSL		0x0100	/* specific action on openssl */
/*!!!*/

#define XIOCLOSE_UNSPEC		0x0000	/* after init, when no end-close... option */
#define XIOCLOSE_NONE		0x0001	/* no action */
#define XIOCLOSE_CLOSE		0x0002	/* close() */
#define XIOCLOSE_SIGTERM	0x0003	/* send SIGTERM to sub process */
#define XIOCLOSE_SIGKILL	0x0004	/* send SIGKILL to sub process */
#define XIOCLOSE_CLOSE_SIGTERM	0x0005	/* close fd, then send SIGTERM */
#define XIOCLOSE_CLOSE_SIGKILL	0x0006	/* close fd, then send SIGKILL */
#define XIOCLOSE_SLEEP_SIGTERM	0x0007	/* short sleep, then SIGTERM */
#define XIOCLOSE_OPENSSL	0x0100
#define XIOCLOSE_READLINE	0x0101

/* these are the values allowed for the "enum xiotag  tag" flag of the "struct
   single" and "union bipipe" (xiofile_t) structures. */
enum xiotag {
   XIO_TAG_INVALID,	/* the record is not in use */
   XIO_TAG_RDONLY,	/* this is a single read-only stream */
   XIO_TAG_WRONLY,	/* this is a single write-only stream */
   XIO_TAG_RDWR,	/* this is a single read-write stream */
   XIO_TAG_DUAL		/* this is a dual stream, consisting of two single
			   streams */
} ;


union bipipe;


#define XIOADDR_ENDPOINT 0	/* endpoint address */
#define XIOADDR_INTER 1	/* inter address */
#define XIOADDR_SYS XIOADDR_ENDPOINT
#define XIOADDR_PROT XIOADDR_INTER

struct xioaddr_inter_desc {
   int tag;		/* 0: endpoint addr; 1: inter addr */
   const char *defname;	/* main (canonical) name of address */
   int numparams;	/* number of required parameters */
   int leftdirs;	/* set of data directions supported on left side:
			   e.g. XIOBIT_RDONLY|XIOBIT_WRONLY|XIOBIT_RDWR */
   unsigned groups;
   int howtoshut;
   int howtoclose;
   int (*func)(int argc, const char *argv[], struct opt *opts, int rw, union bipipe *fd, unsigned groups,
	       int arg1, int arg2, int arg3);
   int arg1;
   int arg2;
   int arg3;
   int rightdirs;
#if WITH_HELP
   const char *syntax;
#endif
} ;

struct xioaddr_endpoint_desc {
   int tag;		/* 0: endpoint addr; 1: inter addr */
   const char *defname;	/* main (canonical) name of address */
   int numparams;	/* number of required parameters */
   int leftdirs;
   unsigned groups;
   int howtoshut;
   int howtoclose;
   int (*func)(int argc, const char *argv[], struct opt *opts, int rw, union bipipe *fd, unsigned groups,
	       int arg1, int arg2, int arg3);
   int arg1;
   int arg2;
   int arg3;
#if WITH_HELP
   const char *syntax;
#endif
} ;


struct xioaddr_common_desc {
   int tag;		/* 0: endpoint addr; 1: inter addr */
   const char *defname;	/* main (canonical) name of address */
   int numparams;	/* number of required parameters */
   int leftdirs;
   unsigned groups;
   int howtoshut;
   int howtoclose;
} ;


union xioaddr_desc {
   int tag;		/* 0: endpoint addr; 1: inter addr */
   struct xioaddr_common_desc common_desc;
   struct xioaddr_inter_desc inter_desc;
   struct xioaddr_endpoint_desc endpoint_desc;
} ;

union xioaddr_descp {
   struct xioaddr_common_desc *common_desc;
   int *tag;		/* 0: endpoint addr; 1: inter addr */
   struct xioaddr_inter_desc *inter_desc;
   struct xioaddr_endpoint_desc *endpoint_desc;
} ;


/*!!! this to xio-sockd4.h */
struct socks4head {
   uint8_t  version;
   uint8_t  action;
   uint16_t port;
   uint32_t dest;
} ;

/* global XIO options/parameters */
typedef struct {
   bool strictopts;
   const char *pipesep;
   const char *paramsep;
   const char *optionsep;
   char ip4portsep;
   char ip6portsep;	/* do not change, might be hardcoded somewhere! */
   const char *syslogfac;	/* syslog facility (only with mixed mode) */
   char default_ip;	/* default prot.fam for IP based listen ('4' or '6') */
   char preferred_ip;	/* preferred prot.fam. for name resolution ('0' for
			   unspecified, '4', or '6') */
   char *reversechar;
   char *chainsep;
   size_t bufsiz;
   bool verbose;
   bool verbhex;
   bool debug;
   char logopt;		/* y..syslog; s..stderr; f..file; m..mixed */
   struct timeval total_timeout;/* when nothing happens, die after seconds */
   struct timeval pollintv;	/* with ignoreeof, reread after seconds */
   struct timeval closwait;	/* after close of x, die after seconds */
   bool lefttoright;	/* first addr ro, second addr wo */
   bool righttoleft;	/* first addr wo, second addr ro */
} xioopts_t;

/* pack the description of a lock file */
typedef struct {
   const char     *lockfile;	/* name of lockfile; NULL if no locking */
   bool            waitlock;	/* dont't exit when already locked */
   struct timespec intervall;	/* polling intervall */
} xiolock_t;

#define MAXARGV 8

/* a non-dual file descriptor */ 
typedef struct single {
   enum xiotag tag;	/* see  enum xiotag  */
   const union xioaddr_desc *addrdesc;
   int    flags;
   /* until here, keep consistent with bipipe.common !!! */
#if WITH_RETRY
   unsigned int retry;	/* retry opening this many times */
   bool forever;	/* retry opening forever */
   struct timespec intervall;	/* wait so long between retries */
#endif /* WITH_RETRY */
   bool   ignoreeof;	/* option ignoreeof; do not pass eof condition to app*/
   int    eof;		/* 1..exec'd child has died, but no explicit eof
			   occurred 
			   2..fd0 has reached EOF (definitely; never with
			   ignoreeof! */
   size_t wsize;	/* write always this size; 0..all available */
   size_t readbytes;	/* read only so many bytes; 0...unlimited */
   size_t actbytes;	/* so many bytes still to be read (when readbytes!=0)*/
   xiolock_t lock;	/* parameters of lockfile */
   bool      havelock;	/* we are happy owner of the above lock */
   /* until here, keep consistent with bipipe.dual ! */
   int reverse;		/* valid during parse and overload, before open:
			   will this (inter) address be integrated forward or
			   reverse? */
   const union xioaddr_desc **addrdescs;
			/* valid after parse, before overload:
			   the list of possible address descriptors derived
			   from addr keyword, one of which will be selected by
			   context and num of parameters */
   int    closing;	/* 0..write channel is up, 1..just shutdown write ch.,
			   2..counting down closing timeout, 3..no more write
			   possible */
   bool	     cool_write;	/* downlevel EPIPE, ECONNRESET to notice */
   int argc;		/* number of fields in argv */
   const char *argv[MAXARGV];	/* address keyword, required args */
   struct opt *opts;	/* the options of this address */
   int    lineterm;	/* 0..dont touch; 1..CR; 2..CRNL on extern data */
   int    fd1;
   int    fd2;
   enum {
      FDTYPE_SINGLE,	/* only fd1 is in use, for reading and/or writing */
      FDTYPE_DOUBLE	/* fd2 is in use too - for writing */
   } fdtype;
   pid_t  subaddrpid;	/* pid of subaddress (process handling next addr in
			   chain) */
   int    subaddrstat;	/* state of subaddress process
			   0...no sub address process
			   1...running
			   -1...ended (aborted?) */
   int    subaddrexit;	/* if subaddstat==-1: exit code of sub process */
   bool   opt_unlink_close;	/* option unlink_close */
   char  *unlink_close;	/* name of a symlink or unix socket to be removed */
   int dtype;
   int howtoshut;	/* method for shutting down xfds */
   int howtoclose;	/* method for closing xfds */
#if _WITH_SOCKET
   union sockaddr_union peersa;
   socklen_t salen;
#endif /* _WITH_SOCKET */
#if WITH_TERMIOS
   bool ttyvalid;		/* the following struct is valid */
   struct termios savetty;	/* save orig tty settings for later restore */
#endif /* WITH_TERMIOS */
   /*0 const char *name;*/		/* only with END_UNLINK */
   struct {			/* this was for exec only, now for embedded */
      pid_t pid;		/* child PID, with EXEC: */
      int (*sigchild)(struct single *);	/* callback after sigchild */
   } child;
   pid_t ppid;			/* parent pid, only if we send it signals */
   pthread_t subthread;		/* thread handling next inter-addr in chain */
   union {
#if 0
      struct {
	 int fdout;		/* use fd for output */
      } bipipe;
#endif
#if _WITH_SOCKET
      struct {
	 struct timeval connect_timeout; /* how long to hang in connect() */
	 union sockaddr_union la;	/* local socket address */
	 bool emptyiseof;	/* with dgram: empty packet means EOF */
	 bool dorange;
	 union xiorange_union range;	/* restrictions for peer address */
#if _WITH_IP4 || _WITH_IP6
	 struct {
	    unsigned int res_opts[2];	/* bits to be set in _res.options are
				       at [0], bits to be cleared are at [1] */
	    bool   dosourceport;
	    uint16_t sourceport;	/* host byte order */
	    bool     lowport;
#if (WITH_TCP || WITH_UDP) && WITH_LIBWRAP
	    bool   dolibwrap;
	    char    *libwrapname;
	    char    *tcpwrap_etc;
	    char    *hosts_allow_table;
	    char    *hosts_deny_table;
#endif
	 } ip;
#endif /* _WITH_IP4 || _WITH_IP6 */
      } socket;
#endif /* _WITH_SOCKET */
      struct {
	 pid_t pid;		/* child PID, with EXEC: */
	 int fdout;		/* use fd for output if two pipes */
      } exec;
#if WITH_READLINE
      struct {
	 char *history_file;
	 char *prompt;		/* static prompt, passed to readline() */
	 size_t dynbytes;	/* length of buffer for dynamic prompt */
	 char *dynprompt;	/* the dynamic prompt */
	 char *dynend;		/* current end of dynamic prompt */
#if HAVE_REGEX_H
	 bool    hasnoecho;	/* following regex is set */
	 regex_t noecho;	/* if it matches the prompt, input is silent */
#endif
      } readline;
#endif /* WITH_READLINE */
#if WITH_SOCKS4_SERVER
      struct {
	 int state;		/* state of socks4 protocol negotiation */
	 /* we cannot rely on all request data arriving at once */
	 struct socks4head head;
	 char *userid;
	 char *hostname;	/* socks4a only */
	 /* the following structs are an experiment for future synchronization
	    mechanisms */
	 struct {
	    size_t canrecv;
	    size_t wantwrite;
	    void *inbuff;
	    size_t inbuflen;	/* length of buffer */
	    size_t bytes;	/* current bytes in buffer */
	 } proto;
	 struct {
	    size_t canrecv;
	    size_t wantwrite;
	 } peer_proto;
	 struct {
	    size_t canrecv;
	    size_t wantwrite;
	    int _errno;
	 } data;
	 struct {
	    size_t canrecv;
	    size_t wantwrite;
	 } peer_data;
      } socks4d;
#endif /* WITH_SOCKS4_SERVER */
#if WITH_OPENSSL
      struct {
	 struct timeval connect_timeout; /* how long to hang in connect() */
	 SSL *ssl;
	 SSL_CTX* ctx;
      } openssl;
#endif /* WITH_OPENSSL */
#if WITH_TUN
      struct {
	 short iff_opts[2];	/* ifr flags, using OFUNC_OFFSET_MASKS */
      } tun;
#endif /* WITH_TUN */
#if _WITH_GZIP
      struct {
	 gzFile in;	/* for reading (uncompressing from stream to API) */
	 gzFile out;	/* for writing (compressing from API to stream) */
	 int level;
      } gzip;
#endif /* _WITH_GZIP */
   } para;
} xiosingle_t;

/* rw: 0..read, 1..write, 2..r/w */
/* when implementing a new address type take care of following topics:
   . be aware that xioopen_single is used for O_RDONLY, O_WRONLY, and O_RDWR data
   . which options are allowed (option groups)
   . implement application of all these options
   . set FD_CLOEXEC on new file descriptors BEFORE the cloexec option might be
     applied
   .
*/

typedef union bipipe {
   enum xiotag    tag;
   struct {
      enum xiotag tag;
      const union xioaddr_desc *addrdesc;
      int         flags;
   } common;
   struct single  stream;
   struct {
      enum xiotag tag;
      const union xioaddr_desc *addrdesc;
      int         flags;	/* compatible to fcntl(.., F_GETFL, ..) */
#if WITH_RETRY
      unsigned retry;	/* retry opening this many times */
      bool forever;	/* retry opening forever */
      struct timespec intervall;	/* wait so long between retries */
#endif /* WITH_RETRY */
      bool        ignoreeof;
      int         eof;		/* fd0 has reached EOF */
      size_t      wsize;	/* write always this size; 0..all available */
      size_t readbytes;	/* read only so many bytes; 0...unlimited */
      size_t actbytes;	/* so many bytes still to be read */
      xiolock_t lock;	/* parameters of lockfile */
      bool      havelock;	/* we are happy owner of the above lock */
      /* until here, keep consistent with struct single ! */
      xiosingle_t *stream[2];	/* input stream, output stream */
   } dual;
} xiofile_t;


#define XIO_WRITABLE(s) (((s)->common.flags+1)&2)
#define XIO_READABLE(s) (((s)->common.flags+1)&1)
#define XIO_RDSTREAM(s) (((s)->tag==XIO_TAG_DUAL)?(s)->dual.stream[0]:&(s)->stream)
#define XIO_WRSTREAM(s) (((s)->tag==XIO_TAG_DUAL)?(s)->dual.stream[1]:&(s)->stream)
#define XIO_GETRDFD(s) (((s)->tag==XIO_TAG_DUAL)?(s)->dual.stream[0]->fd1:(s)->stream.fd1)
#define _XIO_GETWRFD(s) (((s)->fdtype==FDTYPE_DOUBLE)?(s)->fd2:(s)->fd1)
#define XIO_GETWRFD(s) (((s)->tag==XIO_TAG_DUAL)?_XIO_GETWRFD((s)->dual.stream[1]):_XIO_GETWRFD(&(s)->stream))
#define XIO_EOF(s) (XIO_RDSTREAM(s)->eof && !XIO_RDSTREAM(s)->ignoreeof)

typedef unsigned long flags_t;

union integral {
   int            u_bool;
   uint8_t        u_byte;
   gid_t          u_gidt;
   int	          u_int;
   long           u_long;
#if HAVE_TYPE_LONGLONG
   long long      u_longlong;
#endif
   double         u_double;
   mode_t         u_modet;
   short          u_short;
   size_t         u_sizet;
   char          *u_string;
   uid_t          u_uidt;
   unsigned int   u_uint;
   unsigned long  u_ulong;
   unsigned short u_ushort;
   uint16_t       u_2bytes;
   void          *u_ptr;
   flags_t        u_flag;
   struct {
      uint8_t    *b_data;
      size_t      b_len;
   }              u_bin;
   struct timeval u_timeval;
#if HAVE_STRUCT_LINGER
   struct linger  u_linger;
#endif /* HAVE_STRUCT_LINGER */
#if HAVE_STRUCT_TIMESPEC	
   struct timespec u_timespec;
#endif /* HAVE_STRUCT_TIMESPEC */
#if HAVE_STRUCT_IP_MREQ || HAVE_STRUCT_IP_MREQN
   struct {
      char *multiaddr;
      char *param2;	/* address, interface */
#if HAVE_STRUCT_IP_MREQN
      char ifindex[IF_NAMESIZE+1];
#endif
   } u_ip_mreq;
#endif
#if WITH_IP4
   in_addr_t  u_ip4addr;
#endif
} ;

/* some aliases */
#define u_off u_long	/* please report when this causes problems */

#if defined(HAVE_BASIC_OFF64_T) && HAVE_BASIC_OFF64_T
#  if HAVE_BASIC_OFF64_T==5
#     define u_off64 u_long
#  elif HAVE_BASIC_OFF64_T==7
#     define u_off64 u_longlong
#  else
#     error "unexpected size of off64_t, please report this as bug"
#  endif
#endif /* defined(HAVE_BASIC_OFF64_T) && HAVE_BASIC_OFF64_T */


/* this handles option instances, for communication between subroutines */
struct opt {
   const struct optdesc *desc;
   union integral value;
} ;

/* with threading, the arguments indirectly passed to xioengine() */
struct threadarg_struct {
   xiofile_t *xfd1;
   xiofile_t *xfd2;
} ;

extern const char *PIPESEP;
extern xiofile_t *sock[XIO_MAXSOCK];

/* return values of xioopensingle */
#define STAT_OK		0
#define STAT_WARNING	1
#define STAT_EXIT	2
#define STAT_NOACTION	3	/* by retropt_* when option not applied */
#define STAT_RETRYNOW	-1	/* only after timeouts useful ? */
#define STAT_RETRYLATER	-2	/* address cannot be opened, but user might
				   change something in the filesystem etc. to
				   make this process succeed later. */
#define STAT_NORETRY	-3	/* address syntax error, not implemented etc;
				   not even by external changes correctable */

extern int xioinitialize(int xioflags);
extern int xio_forked_inchild(void);
extern int xiosetopt(char what, const char *arg);
extern int xioinqopt(char what, char *arg, size_t n);
extern xiofile_t *xioopen(const char *args, int xioflags);
extern xiofile_t *xioopenx(const char *addr, int xioflags, int infd, int outfd);extern int xiosocketpair(xiofile_t **xfd1p, xiofile_t **xfd2p, int how, ...);

extern int xioopensingle(char *addr, xiosingle_t *fd, int xioflags);
extern int xioopenhelp(FILE *of, int level);

/* must be outside function for use by childdied handler */
extern xiofile_t *xioallocfd(void);
extern void xiofreefd(xiofile_t *xfd);

extern int xiosetsigchild(xiofile_t *xfd, int (*callback)(struct single *));
extern int xiosetchilddied(void);
extern int xio_opt_signal(pid_t pid, int signum);

extern void *xioengine(void *thread_arg);
extern int _socat(xiofile_t *xfd1, xiofile_t *xfd2);
extern ssize_t xioread(xiofile_t *sock1, void *buff, size_t bufsiz);
extern ssize_t xiopending(xiofile_t *sock1);
extern ssize_t xiowrite(xiofile_t *sock1, const void *buff, size_t bufsiz);
extern int xiotransfer(xiofile_t *inpipe, xiofile_t *outpipe,
		unsigned char **buff, size_t bufsiz, bool righttoleft);
extern int xioshutdown(xiofile_t *sock, int how);

extern int xioclose(xiofile_t *sock);
extern void xioexit(void);

extern int (*xiohook_newchild)(void);	/* xio calls this function from a new child process */
extern int socat_sigchild(struct single *file);


extern xioopts_t xioopts, *xioparams;


#endif /* !defined(__xio_h_included) */