1 /* $OpenBSD: expand.h,v 1.6 2005/03/30 17:16:37 deraadt Exp $ */ 2 3 /* 4 * Expanding strings 5 */ 6 7 #define X_EXTRA 8 /* this many extra bytes in X string */ 8 9 #if 0 /* Usage */ 10 XString xs; 11 char *xp; 12 13 Xinit(xs, xp, 128, ATEMP); /* allocate initial string */ 14 while ((c = generate()) { 15 Xcheck(xs, xp); /* expand string if necessary */ 16 Xput(xs, xp, c); /* add character */ 17 } 18 return Xclose(xs, xp); /* resize string */ 19 /* 20 * NOTE: 21 * The Xcheck and Xinit macros have a magic + X_EXTRA in the lengths. 22 * This is so that you can put up to X_EXTRA characters in a XString 23 * before calling Xcheck. (See yylex in lex.c) 24 */ 25 #endif /* 0 */ 26 27 typedef struct XString { 28 char *end, *beg; /* end, begin of string */ 29 size_t len; /* length */ 30 Area *areap; /* area to allocate/free from */ 31 } XString; 32 33 typedef char * XStringP; 34 35 /* initialize expandable string */ 36 #define Xinit(xs, xp, length, area) do { \ 37 (xs).len = length; \ 38 (xs).areap = (area); \ 39 (xs).beg = alloc((xs).len + X_EXTRA, (xs).areap); \ 40 (xs).end = (xs).beg + (xs).len; \ 41 xp = (xs).beg; \ 42 } while (0) 43 44 /* stuff char into string */ 45 #define Xput(xs, xp, c) (*xp++ = (c)) 46 47 /* check if there are at least n bytes left */ 48 #define XcheckN(xs, xp, n) do { \ 49 int more = ((xp) + (n)) - (xs).end; \ 50 if (more > 0) \ 51 xp = Xcheck_grow_(&xs, xp, more); \ 52 } while (0) 53 54 /* check for overflow, expand string */ 55 #define Xcheck(xs, xp) XcheckN(xs, xp, 1) 56 57 /* free string */ 58 #define Xfree(xs, xp) afree((void*) (xs).beg, (xs).areap) 59 60 /* close, return string */ 61 #define Xclose(xs, xp) (char*) aresize((void*)(xs).beg, \ 62 (size_t)((xp) - (xs).beg), (xs).areap) 63 /* begin of string */ 64 #define Xstring(xs, xp) ((xs).beg) 65 66 #define Xnleft(xs, xp) ((xs).end - (xp)) /* may be less than 0 */ 67 #define Xlength(xs, xp) ((xp) - (xs).beg) 68 #define Xsize(xs, xp) ((xs).end - (xs).beg) 69 #define Xsavepos(xs, xp) ((xp) - (xs).beg) 70 #define Xrestpos(xs, xp, n) ((xs).beg + (n)) 71 72 char * Xcheck_grow_(XString *xsp, char *xp, int more); 73 74 /* 75 * expandable vector of generic pointers 76 */ 77 78 typedef struct XPtrV { 79 void **cur; /* next avail pointer */ 80 void **beg, **end; /* begin, end of vector */ 81 } XPtrV; 82 83 #define XPinit(x, n) do { \ 84 void **vp__; \ 85 vp__ = (void**) alloc(sizeofN(void*, n), ATEMP); \ 86 (x).cur = (x).beg = vp__; \ 87 (x).end = vp__ + n; \ 88 } while (0) 89 90 #define XPput(x, p) do { \ 91 if ((x).cur >= (x).end) { \ 92 int n = XPsize(x); \ 93 (x).beg = (void**) aresize((void*) (x).beg, \ 94 sizeofN(void*, n*2), ATEMP); \ 95 (x).cur = (x).beg + n; \ 96 (x).end = (x).cur + n; \ 97 } \ 98 *(x).cur++ = (p); \ 99 } while (0) 100 101 #define XPptrv(x) ((x).beg) 102 #define XPsize(x) ((x).cur - (x).beg) 103 104 #define XPclose(x) (void**) aresize((void*)(x).beg, \ 105 sizeofN(void*, XPsize(x)), ATEMP) 106 107 #define XPfree(x) afree((void*) (x).beg, ATEMP) 108