vfscanf.c raw
1 #include <stdlib.h>
2 #include <stdarg.h>
3 #include <ctype.h>
4 #include <wchar.h>
5 #include <wctype.h>
6 #include <limits.h>
7 #include <string.h>
8 #include <stdint.h>
9
10 #include "stdio_impl.h"
11 #include "shgetc.h"
12 #include "intscan.h"
13 #include "floatscan.h"
14
15 #define SIZE_hh -2
16 #define SIZE_h -1
17 #define SIZE_def 0
18 #define SIZE_l 1
19 #define SIZE_L 2
20 #define SIZE_ll 3
21
22 static void store_int(void *dest, int size, unsigned long long i)
23 {
24 if (!dest) return;
25 switch (size) {
26 case SIZE_hh:
27 *(char *)dest = i;
28 break;
29 case SIZE_h:
30 *(short *)dest = i;
31 break;
32 case SIZE_def:
33 *(int *)dest = i;
34 break;
35 case SIZE_l:
36 *(long *)dest = i;
37 break;
38 case SIZE_ll:
39 *(long long *)dest = i;
40 break;
41 }
42 }
43
44 static void *arg_n(va_list ap, unsigned int n)
45 {
46 void *p;
47 unsigned int i;
48 va_list ap2;
49 va_copy(ap2, ap);
50 for (i=n; i>1; i--) va_arg(ap2, void *);
51 p = va_arg(ap2, void *);
52 va_end(ap2);
53 return p;
54 }
55
56 int vfscanf(FILE *restrict f, const char *restrict fmt, va_list ap)
57 {
58 int width;
59 int size;
60 int alloc = 0;
61 int base;
62 const unsigned char *p;
63 int c, t;
64 char *s;
65 wchar_t *wcs;
66 mbstate_t st;
67 void *dest=NULL;
68 int invert;
69 int matches=0;
70 unsigned long long x;
71 long double y;
72 off_t pos = 0;
73 unsigned char scanset[257];
74 size_t i, k;
75 wchar_t wc;
76
77 FLOCK(f);
78
79 if (!f->rpos) __toread(f);
80 if (!f->rpos) goto input_fail;
81
82 for (p=(const unsigned char *)fmt; *p; p++) {
83
84 alloc = 0;
85
86 if (isspace(*p)) {
87 while (isspace(p[1])) p++;
88 shlim(f, 0);
89 while (isspace(shgetc(f)));
90 shunget(f);
91 pos += shcnt(f);
92 continue;
93 }
94 if (*p != '%' || p[1] == '%') {
95 shlim(f, 0);
96 if (*p == '%') {
97 p++;
98 while (isspace((c=shgetc(f))));
99 } else {
100 c = shgetc(f);
101 }
102 if (c!=*p) {
103 shunget(f);
104 if (c<0) goto input_fail;
105 goto match_fail;
106 }
107 pos += shcnt(f);
108 continue;
109 }
110
111 p++;
112 if (*p=='*') {
113 dest = 0; p++;
114 } else if (isdigit(*p) && p[1]=='$') {
115 dest = arg_n(ap, *p-'0'); p+=2;
116 } else {
117 dest = va_arg(ap, void *);
118 }
119
120 for (width=0; isdigit(*p); p++) {
121 width = 10*width + *p - '0';
122 }
123
124 if (*p=='m') {
125 wcs = 0;
126 s = 0;
127 alloc = !!dest;
128 p++;
129 } else {
130 alloc = 0;
131 }
132
133 size = SIZE_def;
134 switch (*p++) {
135 case 'h':
136 if (*p == 'h') p++, size = SIZE_hh;
137 else size = SIZE_h;
138 break;
139 case 'l':
140 if (*p == 'l') p++, size = SIZE_ll;
141 else size = SIZE_l;
142 break;
143 case 'j':
144 size = SIZE_ll;
145 break;
146 case 'z':
147 case 't':
148 size = SIZE_l;
149 break;
150 case 'L':
151 size = SIZE_L;
152 break;
153 case 'd': case 'i': case 'o': case 'u': case 'x':
154 case 'a': case 'e': case 'f': case 'g':
155 case 'A': case 'E': case 'F': case 'G': case 'X':
156 case 's': case 'c': case '[':
157 case 'S': case 'C':
158 case 'p': case 'n':
159 p--;
160 break;
161 default:
162 goto fmt_fail;
163 }
164
165 t = *p;
166
167 /* C or S */
168 if ((t&0x2f) == 3) {
169 t |= 32;
170 size = SIZE_l;
171 }
172
173 switch (t) {
174 case 'c':
175 if (width < 1) width = 1;
176 case '[':
177 break;
178 case 'n':
179 store_int(dest, size, pos);
180 /* do not increment match count, etc! */
181 continue;
182 default:
183 shlim(f, 0);
184 while (isspace(shgetc(f)));
185 shunget(f);
186 pos += shcnt(f);
187 }
188
189 shlim(f, width);
190 if (shgetc(f) < 0) goto input_fail;
191 shunget(f);
192
193 switch (t) {
194 case 's':
195 case 'c':
196 case '[':
197 if (t == 'c' || t == 's') {
198 memset(scanset, -1, sizeof scanset);
199 scanset[0] = 0;
200 if (t == 's') {
201 scanset[1+'\t'] = 0;
202 scanset[1+'\n'] = 0;
203 scanset[1+'\v'] = 0;
204 scanset[1+'\f'] = 0;
205 scanset[1+'\r'] = 0;
206 scanset[1+' '] = 0;
207 }
208 } else {
209 if (*++p == '^') p++, invert = 1;
210 else invert = 0;
211 memset(scanset, invert, sizeof scanset);
212 scanset[0] = 0;
213 if (*p == '-') p++, scanset[1+'-'] = 1-invert;
214 else if (*p == ']') p++, scanset[1+']'] = 1-invert;
215 for (; *p != ']'; p++) {
216 if (!*p) goto fmt_fail;
217 if (*p=='-' && p[1] && p[1] != ']')
218 for (c=p++[-1]; c<*p; c++)
219 scanset[1+c] = 1-invert;
220 scanset[1+*p] = 1-invert;
221 }
222 }
223 wcs = 0;
224 s = 0;
225 i = 0;
226 k = t=='c' ? width+1U : 31;
227 if (size == SIZE_l) {
228 if (alloc) {
229 wcs = malloc(k*sizeof(wchar_t));
230 if (!wcs) goto alloc_fail;
231 } else {
232 wcs = dest;
233 }
234 st = (mbstate_t){0};
235 while (scanset[(c=shgetc(f))+1]) {
236 switch (mbrtowc(&wc, &(char){c}, 1, &st)) {
237 case -1:
238 goto input_fail;
239 case -2:
240 continue;
241 }
242 if (wcs) wcs[i++] = wc;
243 if (alloc && i==k) {
244 k+=k+1;
245 wchar_t *tmp = realloc(wcs, k*sizeof(wchar_t));
246 if (!tmp) goto alloc_fail;
247 wcs = tmp;
248 }
249 }
250 if (!mbsinit(&st)) goto input_fail;
251 } else if (alloc) {
252 s = malloc(k);
253 if (!s) goto alloc_fail;
254 while (scanset[(c=shgetc(f))+1]) {
255 s[i++] = c;
256 if (i==k) {
257 k+=k+1;
258 char *tmp = realloc(s, k);
259 if (!tmp) goto alloc_fail;
260 s = tmp;
261 }
262 }
263 } else if ((s = dest)) {
264 while (scanset[(c=shgetc(f))+1])
265 s[i++] = c;
266 } else {
267 while (scanset[(c=shgetc(f))+1]);
268 }
269 shunget(f);
270 if (!shcnt(f)) goto match_fail;
271 if (t == 'c' && shcnt(f) != width) goto match_fail;
272 if (alloc) {
273 if (size == SIZE_l) *(wchar_t **)dest = wcs;
274 else *(char **)dest = s;
275 }
276 if (t != 'c') {
277 if (wcs) wcs[i] = 0;
278 if (s) s[i] = 0;
279 }
280 break;
281 case 'p':
282 case 'X':
283 case 'x':
284 base = 16;
285 goto int_common;
286 case 'o':
287 base = 8;
288 goto int_common;
289 case 'd':
290 case 'u':
291 base = 10;
292 goto int_common;
293 case 'i':
294 base = 0;
295 int_common:
296 x = __intscan(f, base, 0, ULLONG_MAX);
297 if (!shcnt(f)) goto match_fail;
298 if (t=='p' && dest) *(void **)dest = (void *)(uintptr_t)x;
299 else store_int(dest, size, x);
300 break;
301 case 'a': case 'A':
302 case 'e': case 'E':
303 case 'f': case 'F':
304 case 'g': case 'G':
305 y = __floatscan(f, size, 0);
306 if (!shcnt(f)) goto match_fail;
307 if (dest) switch (size) {
308 case SIZE_def:
309 *(float *)dest = y;
310 break;
311 case SIZE_l:
312 *(double *)dest = y;
313 break;
314 case SIZE_L:
315 *(long double *)dest = y;
316 break;
317 }
318 break;
319 }
320
321 pos += shcnt(f);
322 if (dest) matches++;
323 }
324 if (0) {
325 fmt_fail:
326 alloc_fail:
327 input_fail:
328 if (!matches) matches--;
329 match_fail:
330 if (alloc) {
331 free(s);
332 free(wcs);
333 }
334 }
335 FUNLOCK(f);
336 return matches;
337 }
338
339 weak_alias(vfscanf,__isoc99_vfscanf);
340