/*->h.zmodem */

/*
 *   Z M O D E M . H     Manifest constants for ZMODEM
 *    application to application file transfer protocol
 *    05-23-87  Chuck Forsberg Omen Technology Inc
 */

#define ZPAD '*'       /* 052 Padding character begins frames */
#define ZDLE 030       /* Ctrl-X Zmodem escape - `ala BISYNC DLE */
#define ZDLEE (ZDLE~0100)      /* Escaped ZDLE as transmitted */
#define ZBIN 'A'       /* Binary frame indicator */
#define ZHEX 'B'       /* HEX frame indicator */
#define ZBIN32 'C'     /* Binary frame with 32 bit FCS */

/* Frame types (see array "frametypes" in zm.c) */
#define ZRQINIT        0       /* Request receive init */
#define ZRINIT 1       /* Receive init */
#define ZSINIT 2       /* Send init sequence (optional) */
#define ZACK 3         /* ACK to above */
#define ZFILE 4        /* File name from sender */
#define ZSKIP 5        /* To sender: skip this file */
#define ZNAK 6         /* Last packet was garbled */
#define ZABORT 7       /* Abort batch transfers */
#define ZFIN 8         /* Finish session */
#define ZRPOS 9                /* Resume data trans at this position */
#define ZDATA 10       /* Data packet(s) follow */
#define ZEOF 11                /* End of file */
#define ZFERR 12       /* Fatal Read or Write error Detected */
#define ZCRC 13                /* Request for file CRC and response */
#define ZCHALLENGE 14  /* Receiver's Challenge */
#define ZCOMPL 15      /* Request is complete */
#define ZCAN 16                /* Other end canned session with CAN*5 */
#define ZFREECNT 17    /* Request for free bytes on filesystem */
#define ZCOMMAND 18    /* Command from sending program */
#define ZSTDERR 19     /* Output to standard error, data follows */

/* ZDLE sequences */
#define ZCRCE 'h'      /* CRC next, frame ends, header packet follows */
#define ZCRCG 'i'      /* CRC next, frame continues nonstop */
#define ZCRCQ 'j'      /* CRC next, frame continues, ZACK expected */
#define ZCRCW 'k'      /* CRC next, ZACK expected, end of frame */
#define ZRUB0 'l'      /* Translate to rubout 0177 */
#define ZRUB1 'm'      /* Translate to rubout 0377 */

/* zdlread return values (internal) */
/* -1 is general error, -2 is timeout */
#define GOTOR 0400
#define GOTCRCE (ZCRCE|GOTOR)  /* ZDLE-ZCRCE received */
#define GOTCRCG (ZCRCG|GOTOR)  /* ZDLE-ZCRCG received */
#define GOTCRCQ (ZCRCQ|GOTOR)  /* ZDLE-ZCRCQ received */
#define GOTCRCW (ZCRCW|GOTOR)  /* ZDLE-ZCRCW received */
#define GOTCAN (GOTOR|030)     /* CAN*5 seen */

/* Byte positions within header array */
#define ZF0    3       /* First flags byte */
#define ZF1    2
#define ZF2    1
#define ZF3    0
#define ZP0    0       /* Low order 8 bits of position */
#define ZP1    1
#define ZP2    2
#define ZP3    3       /* High order 8 bits of file position */

/* Bit Masks for ZRINIT flags byte ZF0 */
#define CANFDX 01      /* Rx can send and receive true FDX */
#define CANOVIO        02      /* Rx can receive data during disk I/O */
#define CANBRK 04      /* Rx can send a break signal */
#define CANCRY 010     /* Receiver can decrypt */
#define CANLZW 020     /* Receiver can uncompress */
#define CANFC32        040     /* Receiver can use 32 bit Frame Check */
#define ESCCTL 0100    /* Receiver expects ctl chars to be escaped */
#define ESC8   0200    /* Receiver expects 8th bit to be escaped */

/* Parameters for ZSINIT frame */

#define ZATTNLEN 32    /* Max length of attention string */


/* Bit Masks for ZSINIT flags byte ZF0 */

#define TESCCTL 0100   /* Transmitter expects ctl chars to be escaped */
#define TESC8   0200   /* Transmitter expects 8th bit to be escaped */



/* Parameters for ZFILE frame */
/* Conversion options one of these in ZF0 */

#define ZCBIN  1       /* Binary transfer - inhibit conversion */
#define ZCNL   2       /* Convert NL to local end of line convention */
#define ZCRESUM        3       /* Resume interrupted file transfer */


/* Management include options, one of these ored in ZF1 */

#define ZMSKNOLOC      0200    /* Skip file if not present at rx */


/* Management options, one of these ored in ZF1 */

#define ZMMASK 037     /* Mask for the choices below */
#define ZMNEWL 1       /* Transfer if source newer or longer */
#define ZMCRC  2       /* Transfer if different file CRC or length */
#define ZMAPND 3       /* Append contents to existing file (if any) */
#define ZMCLOB 4       /* Replace existing file */
#define ZMNEW  5       /* Transfer if source newer */


       /* Number 5 is alive ... */
#define ZMDIFF 6       /* Transfer if dates or lengths different */
#define ZMPROT 7       /* Protect destination file */


/* Transport options, one of these in ZF2 */

#define ZTLZW  1       /* Lempel-Ziv compression */
#define ZTCRYPT        2       /* Encryption */
#define ZTRLE  3       /* Run Length encoding */


/* Extended options for ZF3, bit encoded */

#define ZXSPARS        64      /* Encoding for sparse file operations */

/* Parameters for ZCOMMAND frame ZF0 (otherwise 0) */

#define ZCACK1 1       /* Acknowledge, then do command */



extern long rclhdr(char * hdr);


/* Globals used by ZMODEM functions */

extern Rxframeind;      /* ZBIN ZBIN32, or ZHEX type of frame received */
extern Rxtype;          /* Type of header received */
extern Rxcount;         /* Count of data bytes received */
extern Zrwindow;        /* RX window size (controls garbage count) */
extern Rxtimeout;       /* Tenths of seconds to wait for something */
extern char Rxhdr[4];   /* Received header */
extern char Txhdr[4];   /* Transmitted header */
extern long Rxpos;      /* Received file position */
extern long Txpos;      /* Transmitted file position */
extern Txfcs32;         /* TURE means send binary frames with 32 bit FCS */
extern Crc32t;          /* Display flag indicating 32 bit CRC being sent */
extern Crc32;           /* Display flag indicating 32 bit CRC being received */
extern Znulls;          /* Number of nulls to send at beginning of ZDATA hdr */
extern char Attn[ZATTNLEN+1];   /* Attention string rx sends to tx on err */

/* End of ZMODEM.H */


extern int zgethdr(char * hdr,int eflag);
extern void zsbhdr(int type,char * hdr);
extern void zshhdr(int type,char * hdr);
extern void zsdata(char * buf,int length,int frameend);
extern int zrdata(char * buf,int length);
extern void stohdr(long pos);
extern long rclhdr(char * hdr);


