diff options
Diffstat (limited to 'Src/ns-eel/nseel-yylex.c')
| -rw-r--r-- | Src/ns-eel/nseel-yylex.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/Src/ns-eel/nseel-yylex.c b/Src/ns-eel/nseel-yylex.c new file mode 100644 index 00000000..073f449d --- /dev/null +++ b/Src/ns-eel/nseel-yylex.c @@ -0,0 +1,162 @@ +/* + Nullsoft Expression Evaluator Library (NS-EEL) + Copyright (C) 1999-2003 Nullsoft, Inc. + + nseel-yylex.c + + This software is provided 'as-is', without any express or implied + warranty. In no event will the authors be held liable for any damages + arising from the use of this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute it + freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + 3. This notice may not be removed or altered from any source distribution. +*/ + + +#include "ns-eel-int.h" + + +#define NBPW 16 +#define EOF (-1) + + +#define ERROR 256 /* yacc's value */ + +static int llset(compileContext *ctx); +static int llinp(compileContext *ctx, char **exp); +static int lexgetc(char **exp) +{ + char c= **exp; + if (c) (*exp)++; + return( c != 0 ? c : -1); +} +static int tst__b(register int c, char tab[]) +{ + return (tab[(c >> 3) & 037] & (1 << (c & 07)) ); +} + +int nseel_gettoken(compileContext *ctx, char *lltb, int lltbsiz) +{ + register char *lp, *tp, *ep; + + tp = lltb; + ep = tp+lltbsiz-1; + for (lp = ctx->llbuf; lp < ctx->llend && tp < ep;) + *tp++ = *lp++; + *tp = 0; + return(tp-lltb); +} + + +int nseel_yylex(compileContext *ctx, char **exp) +{ + register int c, st; + int final, l, llk, i; + register struct lextab *lp; + char *cp; + + while (1) + { + llk = 0; + if (llset(ctx)) return(0); + st = 0; + final = -1; + lp = &nseel_lextab; + + do { + if (lp->lllook && (l = lp->lllook[st])) { + for (c=0; c<NBPW; c++) + if (l&(1<<c)) + ctx->llsave[c] = ctx->llp1; + llk++; + } + if ((i = lp->llfinal[st]) != -1) { + final = i; + ctx->llend = ctx->llp1; + } + if ((c = llinp(ctx,exp)) < 0) + break; + if ((cp = lp->llbrk) && llk==0 && tst__b(c, cp)) { + ctx->llp1--; + break; + } + } while ((st = (*lp->llmove)(lp, c, st)) != -1); + + + if (ctx->llp2 < ctx->llp1) + ctx->llp2 = ctx->llp1; + if (final == -1) { + ctx->llend = ctx->llp1; + if (st == 0 && c < 0) + return(0); + if ((cp = lp->llill) && tst__b(c, cp)) { + continue; + } + return(ERROR); + } + if (c = (final >> 11) & 037) + ctx->llend = ctx->llsave[c-1]; + if ((c = (*lp->llactr)(ctx,final&03777)) >= 0) + return(c); + } +} + +void nseel_llinit(compileContext *ctx) +{ + ctx->llp1 = ctx->llp2 = ctx->llend = ctx->llbuf; + ctx->llebuf = ctx->llbuf + sizeof(ctx->llbuf); + ctx->lleof = ctx->yyline = 0; +} + + +static int llinp(compileContext *ctx, char **exp) +{ + register c; + register struct lextab *lp; + register char *cp; + + lp = &nseel_lextab; + cp = lp->llign; /* Ignore class */ + for (;;) { + /* + * Get the next character from the save buffer (if possible) + * If the save buffer's empty, then return EOF or the next + * input character. Ignore the character if it's in the + * ignore class. + */ + c = (ctx->llp1 < ctx->llp2) ? *ctx->llp1 & 0377 : (ctx->lleof) ? EOF : lexgetc(exp); + if (c >= 0) { /* Got a character? */ + if (cp && tst__b(c, cp)) + continue; /* Ignore it */ + if (ctx->llp1 >= ctx->llebuf) { /* No, is there room? */ + return -1; + } + *ctx->llp1++ = c; /* Store in token buff */ + } else + ctx->lleof = 1; /* Set EOF signal */ + return(c); + } +} + +static int llset(compileContext *ctx) +/* + * Return TRUE if EOF and nothing was moved in the look-ahead buffer + */ +{ + register char *lp1, *lp2; + + for (lp1 = ctx->llbuf, lp2 = ctx->llend; lp2 < ctx->llp2;) + *lp1++ = *lp2++; + ctx->llend = ctx->llp1 = ctx->llbuf; + ctx->llp2 = lp1; + return(ctx->lleof && lp1 == ctx->llbuf); +} |