1 /* 2 * pANS stdio -- vfscanf 3 */ 4 #include "iolib.h" 5 #include <ctype.h> 6 static int icvt_f(FILE *f, va_list *args, int store, int width, int type); 7 static int icvt_x(FILE *f, va_list *args, int store, int width, int type); 8 static int icvt_sq(FILE *f, va_list *args, int store, int width, int type); 9 static int icvt_c(FILE *f, va_list *args, int store, int width, int type); 10 static int icvt_d(FILE *f, va_list *args, int store, int width, int type); 11 static int icvt_i(FILE *f, va_list *args, int store, int width, int type); 12 static int icvt_n(FILE *f, va_list *args, int store, int width, int type); 13 static int icvt_o(FILE *f, va_list *args, int store, int width, int type); 14 static int icvt_p(FILE *f, va_list *args, int store, int width, int type); 15 static int icvt_s(FILE *f, va_list *args, int store, int width, int type); 16 static int icvt_u(FILE *f, va_list *args, int store, int width, int type); 17 static int (*icvt[])(FILE *, va_list *, int, int, int)={ 18 0, 0, 0, 0, 0, 0, 0, 0, /* ^@ ^A ^B ^C ^D ^E ^F ^G */ 19 0, 0, 0, 0, 0, 0, 0, 0, /* ^H ^I ^J ^K ^L ^M ^N ^O */ 20 0, 0, 0, 0, 0, 0, 0, 0, /* ^P ^Q ^R ^S ^T ^U ^V ^W */ 21 0, 0, 0, 0, 0, 0, 0, 0, /* ^X ^Y ^Z ^[ ^\ ^] ^^ ^_ */ 22 0, 0, 0, 0, 0, 0, 0, 0, /* sp ! " # $ % & ' */ 23 0, 0, 0, 0, 0, 0, 0, 0, /* ( ) * + , - . / */ 24 0, 0, 0, 0, 0, 0, 0, 0, /* 0 1 2 3 4 5 6 7 */ 25 0, 0, 0, 0, 0, 0, 0, 0, /* 8 9 : ; < = > ? */ 26 0, 0, 0, 0, 0, icvt_f, 0, icvt_f, /* @ A B C D E F G */ 27 0, 0, 0, 0, 0, 0, 0, 0, /* H I J K L M N O */ 28 0, 0, 0, 0, 0, 0, 0, 0, /* P Q R S T U V W */ 29 icvt_x, 0, 0, icvt_sq,0, 0, 0, 0, /* X Y Z [ \ ] ^ _ */ 30 0, 0, 0, icvt_c, icvt_d, icvt_f, icvt_f, icvt_f, /* ` a b c d e f g */ 31 0, icvt_i, 0, 0, 0, 0, icvt_n, icvt_o, /* h i j k l m n o */ 32 icvt_p, 0, 0, icvt_s, 0, icvt_u, 0, 0, /* p q r s t u v w */ 33 icvt_x, 0, 0, 0, 0, 0, 0, 0, /* x y z { | } ~ ^? */ 34 35 0, 0, 0, 0, 0, 0, 0, 0, 36 0, 0, 0, 0, 0, 0, 0, 0, 37 0, 0, 0, 0, 0, 0, 0, 0, 38 0, 0, 0, 0, 0, 0, 0, 0, 39 0, 0, 0, 0, 0, 0, 0, 0, 40 0, 0, 0, 0, 0, 0, 0, 0, 41 0, 0, 0, 0, 0, 0, 0, 0, 42 0, 0, 0, 0, 0, 0, 0, 0, 43 0, 0, 0, 0, 0, 0, 0, 0, 44 0, 0, 0, 0, 0, 0, 0, 0, 45 0, 0, 0, 0, 0, 0, 0, 0, 46 0, 0, 0, 0, 0, 0, 0, 0, 47 0, 0, 0, 0, 0, 0, 0, 0, 48 0, 0, 0, 0, 0, 0, 0, 0, 49 0, 0, 0, 0, 0, 0, 0, 0, 50 0, 0, 0, 0, 0, 0, 0, 0, 51 52 }; 53 #define ngetc(f) (nread++, getc(f)) 54 #define nungetc(c, f) (--nread, ungetc((c), f)) 55 #define wgetc(c, f, out) if(width--==0) goto out; (c)=ngetc(f) 56 #define wungetc(c, f) (++width, nungetc(c, f)) 57 static int nread, ncvt; 58 static const char *fmtp; 59 60 int vfscanf(FILE *f, const char *s, va_list args){ 61 int c, width, type, store; 62 nread=0; 63 ncvt=0; 64 fmtp=s; 65 for(;*fmtp;fmtp++) switch(*fmtp){ 66 default: 67 if(isspace(*fmtp)){ 68 do 69 c=ngetc(f); 70 while(isspace(c)); 71 if(c==EOF) return ncvt?ncvt:EOF; 72 nungetc(c, f); 73 break; 74 } 75 NonSpecial: 76 c=ngetc(f); 77 if(c==EOF) return ncvt?ncvt:EOF; 78 if(c!=*fmtp){ 79 nungetc(c, f); 80 return ncvt; 81 } 82 break; 83 case '%': 84 fmtp++; 85 if(*fmtp!='*') store=1; 86 else{ 87 store=0; 88 fmtp++; 89 } 90 if('0'<=*fmtp && *fmtp<='9'){ 91 width=0; 92 while('0'<=*fmtp && *fmtp<='9') width=width*10 + *fmtp++ - '0'; 93 } 94 else 95 width=-1; 96 type=*fmtp=='h' || *fmtp=='l' || *fmtp=='L'?*fmtp++:'n'; 97 if(!icvt[*fmtp]) goto NonSpecial; 98 if(!(*icvt[*fmtp])(f, &args, store, width, type)) 99 return ncvt?ncvt:EOF; 100 if(*fmtp=='\0') break; 101 if(store) ncvt++; 102 } 103 return ncvt; 104 } 105 static int icvt_n(FILE *f, va_list *args, int store, int width, int type){ 106 #pragma ref f 107 #pragma ref width 108 if(store){ 109 --ncvt; /* this assignment doesn't count! */ 110 switch(type){ 111 case 'h': *va_arg(*args, short *)=nread; break; 112 case 'n': *va_arg(*args, int *)=nread; break; 113 case 'l': 114 case 'L': *va_arg(*args, long *)=nread; break; 115 } 116 } 117 return 1; 118 } 119 #define SIGNED 1 120 #define UNSIGNED 2 121 #define POINTER 3 122 /* 123 * Generic fixed-point conversion 124 * f is the input FILE *; 125 * args is the va_list * into which to store the number; 126 * store is a flag to enable storing; 127 * width is the maximum field width; 128 * type is 'h' 'l' or 'L', the scanf type modifier; 129 * unsgned is SIGNED, UNSIGNED or POINTER, giving part of the type to store in; 130 * base is the number base -- if 0, C number syntax is used. 131 */ 132 static int icvt_fixed(FILE *f, va_list *args, 133 int store, int width, int type, int unsgned, int base){ 134 unsigned long int num=0; 135 int sign=1, ndig=0, dig; 136 int c; 137 do 138 c=ngetc(f); 139 while(isspace(c)); 140 if(width--==0){ 141 nungetc(c, f); 142 goto Done; 143 } 144 if(c=='+'){ 145 wgetc(c, f, Done); 146 } 147 else if(c=='-'){ 148 sign=-1; 149 wgetc(c, f, Done); 150 } 151 switch(base){ 152 case 0: 153 if(c=='0'){ 154 wgetc(c, f, Done); 155 if(c=='x' || c=='X'){ 156 wgetc(c, f, Done); 157 base=16; 158 } 159 else{ 160 ndig=1; 161 base=8; 162 } 163 } 164 else 165 base=10; 166 break; 167 case 16: 168 if(c=='0'){ 169 wgetc(c, f, Done); 170 if(c=='x' || c=='X'){ 171 wgetc(c, f, Done); 172 } 173 else ndig=1; 174 } 175 break; 176 } 177 while('0'<=c && c<='9' || 'a'<=c && c<='f' || 'A'<=c && c<='F'){ 178 dig='0'<=c && c<='9'?c-'0':'a'<=c && c<='f'?c-'a'+10:c-'A'+10; 179 if(dig>=base) break; 180 ndig++; 181 num=num*base+dig; 182 wgetc(c, f, Done); 183 } 184 nungetc(c, f); 185 Done: 186 if(ndig==0) return 0; 187 if(store){ 188 switch(unsgned){ 189 case SIGNED: 190 switch(type){ 191 case 'h': *va_arg(*args, short *)=num*sign; break; 192 case 'n': *va_arg(*args, int *)=num*sign; break; 193 case 'l': 194 case 'L': *va_arg(*args, long *)=num*sign; break; 195 } 196 break; 197 case UNSIGNED: 198 switch(type){ 199 case 'h': *va_arg(*args, unsigned short *)=num*sign; break; 200 case 'n': *va_arg(*args, unsigned int *)=num*sign; break; 201 case 'l': 202 case 'L': *va_arg(*args, unsigned long *)=num*sign; break; 203 } 204 break; 205 case POINTER: 206 *va_arg(*args, void **)=(void *)(num*sign); break; 207 } 208 } 209 return 1; 210 } 211 static int icvt_d(FILE *f, va_list *args, int store, int width, int type){ 212 return icvt_fixed(f, args, store, width, type, SIGNED, 10); 213 } 214 static int icvt_x(FILE *f, va_list *args, int store, int width, int type){ 215 return icvt_fixed(f, args, store, width, type, UNSIGNED, 16); 216 } 217 static int icvt_o(FILE *f, va_list *args, int store, int width, int type){ 218 return icvt_fixed(f, args, store, width, type, UNSIGNED, 8); 219 } 220 static int icvt_i(FILE *f, va_list *args, int store, int width, int type){ 221 return icvt_fixed(f, args, store, width, type, SIGNED, 0); 222 } 223 static int icvt_u(FILE *f, va_list *args, int store, int width, int type){ 224 return icvt_fixed(f, args, store, width, type, UNSIGNED, 10); 225 } 226 static int icvt_p(FILE *f, va_list *args, int store, int width, int type){ 227 return icvt_fixed(f, args, store, width, type, POINTER, 16); 228 } 229 #define NBUF 509 230 static int icvt_f(FILE *f, va_list *args, int store, int width, int type){ 231 char buf[NBUF+1]; 232 char *s=buf; 233 int c, ndig=0, ndpt=0, nexp=1; 234 if(width<0 || NBUF<width) width=NBUF; /* bug -- no limit specified in ansi */ 235 do 236 c=ngetc(f); 237 while(isspace(c)); 238 if(width--==0){ 239 nungetc(c, f); 240 goto Done; 241 } 242 if(c=='+' || c=='-'){ 243 *s++=c; 244 wgetc(c, f, Done); 245 } 246 while('0'<=c && c<='9' || ndpt==0 && c=='.'){ 247 if(c=='.') ndpt++; 248 else ndig++; 249 *s++=c; 250 wgetc(c, f, Done); 251 } 252 if(c=='e' || c=='E'){ 253 *s++=c; 254 nexp=0; 255 wgetc(c, f, Done); 256 if(c=='+' || c=='-'){ 257 *s++=c; 258 wgetc(c, f, Done); 259 } 260 while('0'<=c && c<='9'){ 261 *s++=c; 262 nexp++; 263 wgetc(c, f, Done); 264 } 265 } 266 nungetc(c, f); 267 Done: 268 if(ndig==0 || nexp==0) return 0; 269 *s='\0'; 270 if(store) switch(type){ 271 case 'h': 272 case 'n': *va_arg(*args, float *)=atof(buf); break; 273 case 'L': /* bug -- should store in a long double */ 274 case 'l': *va_arg(*args, double *)=atof(buf); break; 275 } 276 return 1; 277 } 278 static int icvt_s(FILE *f, va_list *args, int store, int width, int type){ 279 #pragma ref type 280 int c, nn; 281 register char *s; 282 if(store) s=va_arg(*args, char *); 283 do 284 c=ngetc(f); 285 while(isspace(c)); 286 if(width--==0){ 287 nungetc(c, f); 288 goto Done; 289 } 290 nn=0; 291 while(!isspace(c)){ 292 if(c==EOF){ 293 if(nn==0) return 0; 294 else goto Done; 295 } 296 nn++; 297 if(store) *s++=c; 298 wgetc(c, f, Done); 299 } 300 nungetc(c, f); 301 Done: 302 if(store) *s='\0'; 303 return 1; 304 } 305 static int icvt_c(FILE *f, va_list *args, int store, int width, int type){ 306 #pragma ref type 307 int c; 308 register char *s; 309 if(store) s=va_arg(*args, char *); 310 if(width<0) width=1; 311 for(;;){ 312 wgetc(c, f, Done); 313 if(c==EOF) return 0; 314 if(store) *s++=c; 315 } 316 Done: 317 return 1; 318 } 319 static int match(int c, const char *pat){ 320 int ok=1; 321 if(*pat=='^'){ 322 ok=!ok; 323 pat++; 324 } 325 while(pat!=fmtp){ 326 if(pat+2<fmtp && pat[1]=='-'){ 327 if(pat[0]<=c && c<=pat[2] 328 || pat[2]<=c && c<=pat[0]) 329 return ok; 330 pat+=2; 331 } 332 else if(c==*pat) return ok; 333 pat++; 334 } 335 return !ok; 336 } 337 static int icvt_sq(FILE *f, va_list *args, int store, int width, int type){ 338 #pragma ref type 339 int c, nn; 340 register char *s; 341 register const char *pat; 342 pat=++fmtp; 343 if(*fmtp=='^') fmtp++; 344 if(*fmtp!='\0') fmtp++; 345 while(*fmtp!='\0' && *fmtp!=']') fmtp++; 346 if(store) s=va_arg(*args, char *); 347 nn=0; 348 for(;;){ 349 wgetc(c, f, Done); 350 if(c==EOF){ 351 if(nn==0) return 0; 352 else goto Done; 353 } 354 if(!match(c, pat)) break; 355 if(store) *s++=c; 356 nn++; 357 } 358 nungetc(c, f); 359 Done: 360 if(store) *s='\0'; 361 return 1; 362 } 363