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
vfscanf(FILE * f,const char * s,va_list args)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 }
icvt_n(FILE * f,va_list * args,int store,int width,int type)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 */
icvt_fixed(FILE * f,va_list * args,int store,int width,int type,int unsgned,int base)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 }
icvt_d(FILE * f,va_list * args,int store,int width,int type)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 }
icvt_x(FILE * f,va_list * args,int store,int width,int type)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 }
icvt_o(FILE * f,va_list * args,int store,int width,int type)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 }
icvt_i(FILE * f,va_list * args,int store,int width,int type)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 }
icvt_u(FILE * f,va_list * args,int store,int width,int type)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 }
icvt_p(FILE * f,va_list * args,int store,int width,int type)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
icvt_f(FILE * f,va_list * args,int store,int width,int type)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 }
icvt_s(FILE * f,va_list * args,int store,int width,int type)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 nread--;
294 if(nn==0) return 0;
295 else goto Done;
296 }
297 nn++;
298 if(store) *s++=c;
299 wgetc(c, f, Done);
300 }
301 nungetc(c, f);
302 Done:
303 if(store) *s='\0';
304 return 1;
305 }
icvt_c(FILE * f,va_list * args,int store,int width,int type)306 static int icvt_c(FILE *f, va_list *args, int store, int width, int type){
307 #pragma ref type
308 int c;
309 register char *s;
310 if(store) s=va_arg(*args, char *);
311 if(width<0) width=1;
312 for(;;){
313 wgetc(c, f, Done);
314 if(c==EOF) return 0;
315 if(store) *s++=c;
316 }
317 Done:
318 return 1;
319 }
match(int c,const char * pat)320 static int match(int c, const char *pat){
321 int ok=1;
322 if(*pat=='^'){
323 ok=!ok;
324 pat++;
325 }
326 while(pat!=fmtp){
327 if(pat+2<fmtp && pat[1]=='-'){
328 if(pat[0]<=c && c<=pat[2]
329 || pat[2]<=c && c<=pat[0])
330 return ok;
331 pat+=2;
332 }
333 else if(c==*pat) return ok;
334 pat++;
335 }
336 return !ok;
337 }
icvt_sq(FILE * f,va_list * args,int store,int width,int type)338 static int icvt_sq(FILE *f, va_list *args, int store, int width, int type){
339 #pragma ref type
340 int c, nn;
341 register char *s;
342 register const char *pat;
343 pat=++fmtp;
344 if(*fmtp=='^') fmtp++;
345 if(*fmtp!='\0') fmtp++;
346 while(*fmtp!='\0' && *fmtp!=']') fmtp++;
347 if(store) s=va_arg(*args, char *);
348 nn=0;
349 for(;;){
350 wgetc(c, f, Done);
351 if(c==EOF){
352 nread--;
353 if(nn==0) return 0;
354 else goto Done;
355 }
356 if(!match(c, pat)) break;
357 if(store) *s++=c;
358 nn++;
359 }
360 nungetc(c, f);
361 Done:
362 if(store) *s='\0';
363 return 1;
364 }
365