1 /*
2 * pANS stdio -- vfscanf
3 */
4 #include "iolib.h"
5 #include <stdarg.h>
6 #include <math.h>
7 #include <ctype.h>
8 static int icvt_f(FILE *f, va_list *args, int store, int width, int type);
9 static int icvt_x(FILE *f, va_list *args, int store, int width, int type);
10 static int icvt_sq(FILE *f, va_list *args, int store, int width, int type);
11 static int icvt_c(FILE *f, va_list *args, int store, int width, int type);
12 static int icvt_d(FILE *f, va_list *args, int store, int width, int type);
13 static int icvt_i(FILE *f, va_list *args, int store, int width, int type);
14 static int icvt_n(FILE *f, va_list *args, int store, int width, int type);
15 static int icvt_o(FILE *f, va_list *args, int store, int width, int type);
16 static int icvt_p(FILE *f, va_list *args, int store, int width, int type);
17 static int icvt_s(FILE *f, va_list *args, int store, int width, int type);
18 static int icvt_u(FILE *f, va_list *args, int store, int width, int type);
19 static int (*icvt[])(FILE *, va_list *, int, int, int)={
20 0, 0, 0, 0, 0, 0, 0, 0, /* ^@ ^A ^B ^C ^D ^E ^F ^G */
21 0, 0, 0, 0, 0, 0, 0, 0, /* ^H ^I ^J ^K ^L ^M ^N ^O */
22 0, 0, 0, 0, 0, 0, 0, 0, /* ^P ^Q ^R ^S ^T ^U ^V ^W */
23 0, 0, 0, 0, 0, 0, 0, 0, /* ^X ^Y ^Z ^[ ^\ ^] ^^ ^_ */
24 0, 0, 0, 0, 0, 0, 0, 0, /* sp ! " # $ % & ' */
25 0, 0, 0, 0, 0, 0, 0, 0, /* ( ) * + , - . / */
26 0, 0, 0, 0, 0, 0, 0, 0, /* 0 1 2 3 4 5 6 7 */
27 0, 0, 0, 0, 0, 0, 0, 0, /* 8 9 : ; < = > ? */
28 0, 0, 0, 0, 0, icvt_f, 0, icvt_f, /* @ A B C D E F G */
29 0, 0, 0, 0, 0, 0, 0, 0, /* H I J K L M N O */
30 0, 0, 0, 0, 0, 0, 0, 0, /* P Q R S T U V W */
31 icvt_x, 0, 0, icvt_sq,0, 0, 0, 0, /* X Y Z [ \ ] ^ _ */
32 0, 0, 0, icvt_c, icvt_d, icvt_f, icvt_f, icvt_f, /* ` a b c d e f g */
33 0, icvt_i, 0, 0, 0, 0, icvt_n, icvt_o, /* h i j k l m n o */
34 icvt_p, 0, 0, icvt_s, 0, icvt_u, 0, 0, /* p q r s t u v w */
35 icvt_x, 0, 0, 0, 0, 0, 0, 0, /* x y z { | } ~ ^? */
36
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 0, 0, 0, 0, 0, 0, 0, 0,
52 0, 0, 0, 0, 0, 0, 0, 0,
53
54 };
55 #define ngetc(f) (nread++, getc(f))
56 #define nungetc(c, f) (--nread, ungetc((c), f))
57 #define wgetc(c, f, out) if(width--==0) goto out; (c)=ngetc(f)
58 #define wungetc(c, f) (++width, nungetc(c, f))
59 static int nread, ncvt;
60 static const char *fmtp;
61
vfscanf(FILE * f,const char * s,va_list args)62 int vfscanf(FILE *f, const char *s, va_list args){
63 int c, width, type, store;
64 nread=0;
65 ncvt=0;
66 fmtp=s;
67 for(;*fmtp;fmtp++) switch(*fmtp){
68 default:
69 if(isspace(*fmtp)){
70 do
71 c=ngetc(f);
72 while(isspace(c));
73 if(c==EOF) return ncvt?ncvt:EOF;
74 nungetc(c, f);
75 break;
76 }
77 NonSpecial:
78 c=ngetc(f);
79 if(c==EOF) return ncvt?ncvt:EOF;
80 if(c!=*fmtp){
81 nungetc(c, f);
82 return ncvt;
83 }
84 break;
85 case '%':
86 fmtp++;
87 if(*fmtp!='*') store=1;
88 else{
89 store=0;
90 fmtp++;
91 }
92 if('0'<=*fmtp && *fmtp<='9'){
93 width=0;
94 while('0'<=*fmtp && *fmtp<='9') width=width*10 + *fmtp++ - '0';
95 }
96 else
97 width=-1;
98 type=*fmtp=='h' || *fmtp=='l' || *fmtp=='L'?*fmtp++:'n';
99 if(!icvt[*fmtp]) goto NonSpecial;
100 if(!(*icvt[*fmtp])(f, &args, store, width, type))
101 return ncvt?ncvt:EOF;
102 if(*fmtp=='\0') break;
103 if(store) ncvt++;
104 }
105 return ncvt;
106 }
icvt_n(FILE * f,va_list * args,int store,int width,int type)107 static int icvt_n(FILE *f, va_list *args, int store, int width, int type){
108 USED(f, width);
109 if(store){
110 --ncvt; /* this assignment doesn't count! */
111 switch(type){
112 case 'h': *va_arg(*args, short *)=nread; break;
113 case 'n': *va_arg(*args, int *)=nread; break;
114 case 'l':
115 case 'L': *va_arg(*args, long *)=nread; break;
116 }
117 }
118 return 1;
119 }
120 #define SIGNED 1
121 #define UNSIGNED 2
122 #define POINTER 3
123 /*
124 * Generic fixed-point conversion
125 * f is the input FILE *;
126 * args is the va_list * into which to store the number;
127 * store is a flag to enable storing;
128 * width is the maximum field width;
129 * type is 'h' 'l' or 'L', the scanf type modifier;
130 * unsgned is SIGNED, UNSIGNED or POINTER, giving part of the type to store in;
131 * base is the number base -- if 0, C number syntax is used.
132 */
icvt_fixed(FILE * f,va_list * args,int store,int width,int type,int unsgned,int base)133 static int icvt_fixed(FILE *f, va_list *args,
134 int store, int width, int type, int unsgned, int base){
135 unsigned long int num=0;
136 int sign=1, ndig=0, dig;
137 int c;
138 do
139 c=ngetc(f);
140 while(isspace(c));
141 if(width--==0){
142 nungetc(c, f);
143 goto Done;
144 }
145 if(c=='+'){
146 wgetc(c, f, Done);
147 }
148 else if(c=='-'){
149 sign=-1;
150 wgetc(c, f, Done);
151 }
152 switch(base){
153 case 0:
154 if(c=='0'){
155 wgetc(c, f, Done);
156 if(c=='x' || c=='X'){
157 wgetc(c, f, Done);
158 base=16;
159 }
160 else{
161 ndig=1;
162 base=8;
163 }
164 }
165 else
166 base=10;
167 break;
168 case 16:
169 if(c=='0'){
170 wgetc(c, f, Done);
171 if(c=='x' || c=='X'){
172 wgetc(c, f, Done);
173 }
174 else ndig=1;
175 }
176 break;
177 }
178 while('0'<=c && c<='9' || 'a'<=c && c<='f' || 'A'<=c && c<='F'){
179 dig='0'<=c && c<='9'?c-'0':'a'<=c && c<='f'?c-'a'+10:c-'A'+10;
180 if(dig>=base) break;
181 ndig++;
182 num=num*base+dig;
183 wgetc(c, f, Done);
184 }
185 nungetc(c, f);
186 Done:
187 if(ndig==0) return 0;
188 if(store){
189 switch(unsgned){
190 case SIGNED:
191 switch(type){
192 case 'h': *va_arg(*args, short *)=num*sign; break;
193 case 'n': *va_arg(*args, int *)=num*sign; break;
194 case 'l':
195 case 'L': *va_arg(*args, long *)=num*sign; break;
196 }
197 break;
198 case UNSIGNED:
199 switch(type){
200 case 'h': *va_arg(*args, unsigned short *)=num*sign; break;
201 case 'n': *va_arg(*args, unsigned int *)=num*sign; break;
202 case 'l':
203 case 'L': *va_arg(*args, unsigned long *)=num*sign; break;
204 }
205 break;
206 case POINTER:
207 *va_arg(*args, void **)=(void *)(num*sign); break;
208 }
209 }
210 return 1;
211 }
icvt_d(FILE * f,va_list * args,int store,int width,int type)212 static int icvt_d(FILE *f, va_list *args, int store, int width, int type){
213 return icvt_fixed(f, args, store, width, type, SIGNED, 10);
214 }
icvt_x(FILE * f,va_list * args,int store,int width,int type)215 static int icvt_x(FILE *f, va_list *args, int store, int width, int type){
216 return icvt_fixed(f, args, store, width, type, UNSIGNED, 16);
217 }
icvt_o(FILE * f,va_list * args,int store,int width,int type)218 static int icvt_o(FILE *f, va_list *args, int store, int width, int type){
219 return icvt_fixed(f, args, store, width, type, UNSIGNED, 8);
220 }
icvt_i(FILE * f,va_list * args,int store,int width,int type)221 static int icvt_i(FILE *f, va_list *args, int store, int width, int type){
222 return icvt_fixed(f, args, store, width, type, SIGNED, 0);
223 }
icvt_u(FILE * f,va_list * args,int store,int width,int type)224 static int icvt_u(FILE *f, va_list *args, int store, int width, int type){
225 return icvt_fixed(f, args, store, width, type, UNSIGNED, 10);
226 }
icvt_p(FILE * f,va_list * args,int store,int width,int type)227 static int icvt_p(FILE *f, va_list *args, int store, int width, int type){
228 return icvt_fixed(f, args, store, width, type, POINTER, 16);
229 }
230 #define NBUF 509
icvt_f(FILE * f,va_list * args,int store,int width,int type)231 static int icvt_f(FILE *f, va_list *args, int store, int width, int type){
232 char buf[NBUF+1];
233 char *s=buf;
234 int c, ndig=0, ndpt=0, nexp=1;
235 if(width<0 || NBUF<width) width=NBUF; /* bug -- no limit specified in ansi */
236 do
237 c=ngetc(f);
238 while(isspace(c));
239 if(width--==0){
240 nungetc(c, f);
241 goto Done;
242 }
243 if(c=='+' || c=='-'){
244 *s++=c;
245 wgetc(c, f, Done);
246 }
247 while('0'<=c && c<='9' || ndpt==0 && c=='.'){
248 if(c=='.') ndpt++;
249 else ndig++;
250 *s++=c;
251 wgetc(c, f, Done);
252 }
253 if(c=='e' || c=='E'){
254 *s++=c;
255 nexp=0;
256 wgetc(c, f, Done);
257 if(c=='+' || c=='-'){
258 *s++=c;
259 wgetc(c, f, Done);
260 }
261 while('0'<=c && c<='9'){
262 *s++=c;
263 nexp++;
264 wgetc(c, f, Done);
265 }
266 }
267 nungetc(c, f);
268 Done:
269 if(ndig==0 || nexp==0) return 0;
270 *s='\0';
271 if(store) switch(type){
272 case 'h':
273 case 'n': *va_arg(*args, float *)=atof(buf); break;
274 case 'L': /* bug -- should store in a long double */
275 case 'l': *va_arg(*args, double *)=atof(buf); break;
276 }
277 return 1;
278 }
icvt_s(FILE * f,va_list * args,int store,int width,int type)279 static int icvt_s(FILE *f, va_list *args, int store, int width, int type){
280 int c, nn;
281 register char *s;
282
283 USED(type);
284 s = 0;
285 if(store) s=va_arg(*args, char *);
286 do
287 c=ngetc(f);
288 while(isspace(c));
289 if(width--==0){
290 nungetc(c, f);
291 goto Done;
292 }
293 nn=0;
294 while(!isspace(c)){
295 if(c==EOF){
296 nread--;
297 if(nn==0) return 0;
298 else goto Done;
299 }
300 nn++;
301 if(store) *s++=c;
302 wgetc(c, f, Done);
303 }
304 nungetc(c, f);
305 Done:
306 if(store) *s='\0';
307 return 1;
308 }
icvt_c(FILE * f,va_list * args,int store,int width,int type)309 static int icvt_c(FILE *f, va_list *args, int store, int width, int type){
310 int c;
311 register char *s;
312
313 USED(type);
314 s = 0;
315 if(store) s=va_arg(*args, char *);
316 if(width<0) width=1;
317 for(;;){
318 wgetc(c, f, Done);
319 if(c==EOF) return 0;
320 if(store) *s++=c;
321 }
322 Done:
323 return 1;
324 }
match(int c,const char * pat)325 static int match(int c, const char *pat){
326 int ok=1;
327 if(*pat=='^'){
328 ok=!ok;
329 pat++;
330 }
331 while(pat!=fmtp){
332 if(pat+2<fmtp && pat[1]=='-'){
333 if(pat[0]<=c && c<=pat[2]
334 || pat[2]<=c && c<=pat[0])
335 return ok;
336 pat+=2;
337 }
338 else if(c==*pat) return ok;
339 pat++;
340 }
341 return !ok;
342 }
icvt_sq(FILE * f,va_list * args,int store,int width,int type)343 static int icvt_sq(FILE *f, va_list *args, int store, int width, int type){
344 int c, nn;
345 register char *s;
346 register const char *pat;
347 USED(type);
348 s = 0;
349 pat=++fmtp;
350 if(*fmtp=='^') fmtp++;
351 if(*fmtp!='\0') fmtp++;
352 while(*fmtp!='\0' && *fmtp!=']') fmtp++;
353 if(store) s=va_arg(*args, char *);
354 nn=0;
355 for(;;){
356 wgetc(c, f, Done);
357 if(c==EOF){
358 nread--;
359 if(nn==0) return 0;
360 else goto Done;
361 }
362 if(!match(c, pat)) break;
363 if(store) *s++=c;
364 nn++;
365 }
366 nungetc(c, f);
367 Done:
368 if(store) *s='\0';
369 return 1;
370 }
371