bin/ksh/expand.h

   1 /*      $NetBSD: expand.h,v 1.5 2013/10/18 19:53:34 christos Exp $      */
   2
   3 /*
   4  * Expanding strings
   5  */
   6 /* $Id: expand.h,v 1.5 2013/10/18 19:53:34 christos Exp $ */
   7
   8 #define X_EXTRA         8       /* this many extra bytes in X string */
   9
  10 #if 0                           /* Usage */
  11         XString xs;
  12         char *xp;
  13
  14         Xinit(xs, xp, 128, ATEMP); /* allocate initial string */
  15         while ((c = generate()) {
  16                 Xcheck(xs, xp); /* expand string if necessary */
  17                 Xput(xs, xp, c); /* add character */
  18         }
  19         return Xclose(xs, xp);  /* resize string */
  20 /*
  21  * NOTE:
  22  *     The Xcheck and Xinit macros have a magic + X_EXTRA in the lengths.
  23  *     This is so that you can put up to X_EXTRA characters in a XString
  24  *     before calling Xcheck. (See yylex in lex.c)
  25  */
  26 #endif /* 0 */
  27
  28 typedef struct XString {
  29         char   *end, *beg;      /* end, begin of string */
  30         size_t  len;            /* length */
  31         Area    *areap;         /* area to allocate/free from */
  32 } XString;
  33
  34 typedef char * XStringP;
  35
  36 /* initialize expandable string */
  37 #define Xinit(xs, xp, length, area) do { \
  38                         (xs).len = length; \
  39                         (xs).areap = (area); \
  40                         (xs).beg = alloc((xs).len + X_EXTRA, (xs).areap); \
  41                         (xs).end = (xs).beg + (xs).len; \
  42                         xp = (xs).beg; \
  43                         __USE(xp); \
  44                 } while (0)
  45
  46 /* stuff char into string */
  47 #define Xput(xs, xp, c) (*xp++ = (c))
  48
  49 /* check if there are at least n bytes left */
  50 #define XcheckN(xs, xp, n) do { \
  51                     int more = ((xp) + (n)) - (xs).end; \
  52                     if (more > 0) \
  53                         xp = Xcheck_grow_(&xs, xp, more); \
  54                 } while (0)
  55
  56 /* check for overflow, expand string */
  57 #define Xcheck(xs, xp)  XcheckN(xs, xp, 1)
  58
  59 /* free string */
  60 #define Xfree(xs, xp)   afree((void*) (xs).beg, (xs).areap)
  61
  62 /* close, return string */
  63 #define Xclose(xs, xp)  (char*) aresize((void*)(xs).beg, \
  64                                         (size_t)((xp) - (xs).beg), (xs).areap)
  65 /* begin of string */
  66 #define Xstring(xs, xp) ((xs).beg)
  67
  68 #define Xnleft(xs, xp) ((xs).end - (xp))        /* may be less than 0 */
  69 #define Xlength(xs, xp) ((xp) - (xs).beg)
  70 #define Xsize(xs, xp) ((xs).end - (xs).beg)
  71 #define Xsavepos(xs, xp) ((xp) - (xs).beg)
  72 #define Xrestpos(xs, xp, n) ((xs).beg + (n))
  73
  74 char *  Xcheck_grow_    ARGS((XString *xsp, char *xp, int more));
  75
  76 /*
  77  * expandable vector of generic pointers
  78  */
  79
  80 typedef struct XPtrV {
  81         void  **cur;            /* next avail pointer */
  82         void  **beg, **end;     /* begin, end of vector */
  83 } XPtrV;
  84
  85 #define XPinit(x, n) do { \
  86                         register void **vp__; \
  87                         vp__ = (void**) alloc(sizeofN(void*, n), ATEMP); \
  88                         (x).cur = (x).beg = vp__; \
  89                         (x).end = vp__ + n; \
  90                     } while (0)
  91
  92 #define XPput(x, p) do { \
  93                         if ((x).cur >= (x).end) { \
  94                                 int n = XPsize(x); \
  95                                 (x).beg = (void**) aresize((void*) (x).beg, \
  96                                                    sizeofN(void*, n*2), ATEMP); \
  97                                 (x).cur = (x).beg + n; \
  98                                 (x).end = (x).cur + n; \
  99                         } \
 100                         *(x).cur++ = (p); \
 101                 } while (0)
 102
 103 #define XPptrv(x)       ((x).beg)
 104 #define XPsize(x)       ((x).cur - (x).beg)
 105
 106 #define XPclose(x)      (void**) aresize((void*)(x).beg, \
 107                                          sizeofN(void*, XPsize(x)), ATEMP)
 108
 109 #define XPfree(x)       afree((void*) (x).beg, ATEMP)