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