source.h

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/* SOURCE.H: Entity and source control block structures and definitions.
*/
#define ENTHASH 503         /* Size of entity hash table.  Must be prime. */
/* Entity storage class values for estore member of entity structure. */
#define EST   1               /* String: Tag (usually a fixed STARTGI). */
          /* <MDENTITY sets these:> */
#define ESMD  2               /* String: Markup declaration. */
#define ESMS  3               /* String: Marked section. */
#define ESM   4               /* String: ordinary text. */
               /* <ENTOPEN treats these specially:> */
#define ESS   5               /* ETD: Start-tag. */
#define ESE   6               /* ETD: End-tag. */
#define ESI   7               /* String: PI. */
#define ESX   8               /* String: SDATA general entity. */
#define ESC   9               /* String: CDATA general entity. */
          /* </MDENTITY> <MDEXTID sets these:> */
#define ESFM 10               /* LPU: minimum external (file) storage class. */
#define ESN  10               /* XCB: N/C/SDATA or SUBDOC control block. */
               /* </ENTOPEN> */
#define ESF  11               /* LPU: General entity. */
#define ESP  12               /* LPU: Parameter entity. */
#define ESD  13               /* LPU: Document type definition. */
#define ESL  14               /* LPU: Link process definition. */
#define ESK  15               /* LPU: Data content notation. */
                      /* </MDEXTID> */

union etext {                 /* Entity text. */
     UNIV x;                  /* External ID generated by system. */
     UNCH *c;                 /* Character string. */
     struct ne *n;            /* N/C/SDATA or SUBDOC entity control block. */
};
#define ETEXTSZ sizeof(union etext)
struct entity {               /* Entity control block. */
     struct entity *enext;    /* Next entity in chain. */
     UNCH *ename;	      /* Entity name with length and EOS. */
     UNCH estore;             /* Storage class (see values above). */
     UNCH dflt;		      /* Declared as default entity. */
     UNCH mark;		      /* For use by for sgmlment. */
     union etext etx;         /* Entity text. */
};
#define ENTSZ sizeof(struct entity)
typedef struct entity *PECB;  /* Ptr to entity control block. */
typedef struct entity **TECB; /* Table of entity control blocks. */

struct source {               /* Source control block. */
     struct entity ecb;       /* Entity control block. */
     unsigned long rcnt;      /* Source record number. */
     int ccnt;                /* Source record chars since last RS. */
     int curoff;              /* Offset of curchar (chars read in this block).*/
     UNCH curchar;            /* Current character. */
     UNCH nextchar;	      /* If curchar was DELNONCH, next character. */
     UNIV fcb;                /* SGMLIO fcb ptr returned by OPEN. */
     UNCH *fbuf;              /* 1st char in buffer (0=PEND) or entity text. */
     UNCH *fpos;              /* Current char in buffer or entity text. */
     UNCH pushback;	      /* Character before pend position */
     char copied;	      /* Is this a copy of the internal entity? */
};
#define SCBSZ sizeof(struct source)
typedef struct source *PSCB;  /* Ptr to source control block. */

extern int es;                /* Index of current source in stack. */
extern struct source *scbs;  /* Stack of open sources ("SCB stack"). */

/* Member definitions for source and entity control blocks.
*/
#define SCB (scbs[es])          /* Ptr to current source control block. */

#define ECB     SCB.ecb       /* Pointer to current entity control block. */
#define FBUF    SCB.fbuf      /* Pointer to start of entity buffer. */
#define FPOS    SCB.fpos      /* Pointer to current char of current source. */
#define RSCC    SCB.ccnt      /* CCNT at start of block (across EOB/EOS/EOF). */
#define CCO     SCB.curoff    /* Offset in read buffer of current char. */
#define CC      SCB.curchar   /* Current character of current source entity. */
#define NEXTC   SCB.nextchar  /* Next character in current source entity. */
#define CCNT   (SCB.ccnt+CCO) /* Position of CC in current record (RS=0). */
#define RCNT    SCB.rcnt      /* Position of record in entity (origin=1). */
#define SCBFCB  SCB.fcb       /* Current file control block (if FILESW). */
#define ECBPTR ((ECB.enext))  /* Pointer to this entity's ECB. */
#define ENTITY ((ECB.ename))  /* Current entity name. */
#define FILESW (ECB.estore>=ESFM) /* 1=Entity is external file; 0=internal. */
#define NEWCC     (++FPOS)    /* Get next current character. */
#define REPEATCC  (--FPOS)    /* Repeat previous current character. */
#define COPIEDSW SCB.copied   /* Non-zero means entity was copied. */

struct srh {                  /* Short reference map header. */
     struct srh *enext;       /* Next short reference map in chain. */
     UNCH *ename;	      /* Short reference map name. */
     TECB srhsrm;             /* Ptr to short reference map. */
};
#define SRHSZ (sizeof(struct srh))
typedef struct srh *PSRH;     /* Ptr to short reference map header. */
#define SRMNULL (&dumpecb) /* Dummy ptr to empty short reference map. */

/* Definitions for ENTOPEN/ENTREF return codes.
*/
#define ENTUNDEF -1           /* Callers of ENTOPEN: entity undefined. */
#define ENTLOOP  -2           /* ENTOPEN: endless loop entity. */
#define ENTMAX   -3           /* ENTOPEN: too many open entities. */
#define ENTFILE  -4           /* ENTOPEN: file I/O error. */
#define ENTDATA  -5           /* ENTOPEN: CDATA or SDATA entity. */
#define ENTPI    -6           /* ENTOPEN: PI entity. */

/* Definitions for ENTDATA switches set in contersw.
*/
#define CDECONT   2           /* 0010 CDATA entity referenced. */
#define SDECONT   4           /* 0100 SDATA entity referenced. */
#define NDECONT   8           /* 1000 NDATA entity referenced. */

/* Definitions for manipulating signed source character counters.
*/
#define CTRSET(CTR) (CTR = (int) -(FPOS+1-FBUF))  /* Init source char ctr. */
#define CTRGET(CTR) (CTR + (int)  (FPOS+1-FBUF))  /* Read source char ctr. */