diplodocus.org Git - nmh/blob - h/fmt_scan.h

   1
   2 /*
   3  * fmt_scan.h -- definitions for fmt_scan()
   4  */
   5
   6 /*
   7  * This structure describes an "interesting" component.  It holds
   8  * the name & text from the component (if found) and one piece of
   9  * auxilary info.  The structure for a particular component is located
  10  * by (open) hashing the name and using it as an index into the ptr array
  11  * "wantcomp".  All format entries that reference a particular component
  12  * point to its comp struct (so we only have to do component specific
  13  * processing once.  e.g., parse an address.).
  14  */
  15 struct comp {
  16     char        *c_name;        /* component name (in lower case) */
  17     char        *c_text;        /* component text (if found)      */
  18     struct comp *c_next;        /* hash chain linkage             */
  19     short        c_flags;       /* misc. flags (from fmt_scan)    */
  20     short        c_type;        /* type info   (from fmt_compile) */
  21     union {
  22         struct tws *c_u_tws;
  23         struct mailname *c_u_mn;
  24     } c_un;
  25 };
  26
  27 #define c_tws c_un.c_u_tws
  28 #define c_mn  c_un.c_u_mn
  29
  30 /*
  31  * c_type bits
  32  */
  33 #define CT_ADDR       (1<<0)    /* referenced as address    */
  34 #define CT_DATE       (1<<1)    /* referenced as date       */
  35
  36 /*
  37  * c_flags bits
  38  */
  39 #define CF_TRUE       (1<<0)    /* usually means component is present */
  40 #define CF_PARSED     (1<<1)    /* address/date has been parsed */
  41 #define CF_DATEFAB    (1<<2)    /* datefield fabricated */
  42
  43 extern int fmt_norm;
  44
  45 /*
  46  * Hash table for deciding if a component is "interesting".
  47  */
  48 extern struct comp *wantcomp[128];
  49
  50 /*
  51  * Hash function for component name.  The function should be
  52  * case independent and probably shouldn't involve a routine
  53  * call.  This function is pretty good but will not work on
  54  * single character component names.
  55  */
  56 #define CHASH(nm) (((((nm)[0]) - ((nm)[1])) & 0x1f) + (((nm)[2]) & 0x5f))
  57
  58 /*
  59  * Find a component in the hash table.
  60  */
  61 #define FINDCOMP(comp,name) \
  62                 for (comp = wantcomp[CHASH(name)]; \
  63                      comp && strcmp(comp->c_name,name); \
  64                      comp = comp->c_next) ;
  65
  66 /*
  67  * This structure defines one formatting instruction.
  68  */
  69 struct format {
  70     unsigned char f_type;
  71     char          f_fill;
  72     short         f_width;      /* output field width   */
  73     union {
  74         struct comp *f_u_comp;  /* associated component */
  75         char        *f_u_text;  /* literal text         */
  76         char         f_u_char;  /* literal character    */
  77         int          f_u_value; /* literal value        */
  78     } f_un;
  79 };
  80
  81 #define f_skip f_width          /* instr to skip (false "if") */
  82
  83 #define f_comp  f_un.f_u_comp
  84 #define f_text  f_un.f_u_text
  85 #define f_char  f_un.f_u_char
  86 #define f_value f_un.f_u_value
  87
  88 /*
  89  * prototypes
  90  */
  91 struct format *fmt_scan (struct format *, char *, int, int *);
  92 char *new_fs (char *, char *, char *);
  93 int fmt_compile (char *, struct format **);