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 
store_int(void * dest,int size,unsigned long long i)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 
arg_n(va_list ap,unsigned int n)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 
vfscanf(FILE * restrict f,const char * restrict fmt,va_list ap)56 int vfscanf(FILE *restrict f, const char *restrict fmt, va_list ap)
57 {
58 	int width;
59 	int size;
60 	int alloc;
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 #if !WITH_NO_FP
72 	long double y;
73 #endif
74 	off_t pos = 0;
75 	unsigned char scanset[257];
76 	size_t i, k;
77 	wchar_t wc;
78 
79 	FLOCK(f);
80 
81 	for (p=(const unsigned char *)fmt; *p; p++) {
82 
83 		alloc = 0;
84 
85 		if (isspace(*p)) {
86 			while (isspace(p[1])) p++;
87 			shlim(f, 0);
88 			while (isspace(shgetc(f)));
89 			shunget(f);
90 			pos += shcnt(f);
91 			continue;
92 		}
93 		if (*p != '%' || p[1] == '%') {
94 			shlim(f, 0);
95 			if (*p == '%') {
96 				p++;
97 				while (isspace((c=shgetc(f))));
98 			} else {
99 				c = shgetc(f);
100 			}
101 			if (c!=*p) {
102 				shunget(f);
103 				if (c<0) goto input_fail;
104 				goto match_fail;
105 			}
106 			pos += shcnt(f);
107 			continue;
108 		}
109 
110 		p++;
111 		if (*p=='*') {
112 			dest = 0; p++;
113 		} else if (isdigit(*p) && p[1]=='$') {
114 			dest = arg_n(ap, *p-'0'); p+=2;
115 		} else {
116 			dest = va_arg(ap, void *);
117 		}
118 
119 		for (width=0; isdigit(*p); p++) {
120 			width = 10*width + *p - '0';
121 		}
122 
123 		if (*p=='m') {
124 			wcs = 0;
125 			s = 0;
126 			alloc = !!dest;
127 			p++;
128 		} else {
129 			alloc = 0;
130 		}
131 
132 		size = SIZE_def;
133 		switch (*p++) {
134 		case 'h':
135 			if (*p == 'h') p++, size = SIZE_hh;
136 			else size = SIZE_h;
137 			break;
138 		case 'l':
139 			if (*p == 'l') p++, size = SIZE_ll;
140 			else size = SIZE_l;
141 			break;
142 		case 'j':
143 			size = SIZE_ll;
144 			break;
145 		case 'z':
146 		case 't':
147 			size = SIZE_l;
148 			break;
149 		case 'L':
150 			size = SIZE_L;
151 			break;
152 		case 'd': case 'i': case 'o': case 'u': case 'x':
153 		case 'a': case 'e': case 'f': case 'g':
154 		case 'A': case 'E': case 'F': case 'G': case 'X':
155 		case 's': case 'c': case '[':
156 		case 'S': case 'C':
157 		case 'p': case 'n':
158 			p--;
159 			break;
160 		default:
161 			goto fmt_fail;
162 		}
163 
164 		t = *p;
165 
166 		/* C or S */
167 		if ((t&0x2f) == 3) {
168 			t |= 32;
169 			size = SIZE_l;
170 		}
171 
172 		switch (t) {
173 		case 'c':
174 			if (width < 1) width = 1;
175 		case '[':
176 			break;
177 		case 'n':
178 			store_int(dest, size, pos);
179 			/* do not increment match count, etc! */
180 			continue;
181 		default:
182 			shlim(f, 0);
183 			while (isspace(shgetc(f)));
184 			shunget(f);
185 			pos += shcnt(f);
186 		}
187 
188 		shlim(f, width);
189 		if (shgetc(f) < 0) goto input_fail;
190 		shunget(f);
191 
192 		switch (t) {
193 		case 's':
194 		case 'c':
195 		case '[':
196 			if (t == 'c' || t == 's') {
197 				memset(scanset, -1, sizeof scanset);
198 				scanset[0] = 0;
199 				if (t == 's') {
200 					scanset[1+'\t'] = 0;
201 					scanset[1+'\n'] = 0;
202 					scanset[1+'\v'] = 0;
203 					scanset[1+'\f'] = 0;
204 					scanset[1+'\r'] = 0;
205 					scanset[1+' '] = 0;
206 				}
207 			} else {
208 				if (*++p == '^') p++, invert = 1;
209 				else invert = 0;
210 				memset(scanset, invert, sizeof scanset);
211 				scanset[0] = 0;
212 				if (*p == '-') p++, scanset[1+'-'] = 1-invert;
213 				else if (*p == ']') p++, scanset[1+']'] = 1-invert;
214 				for (; *p != ']'; p++) {
215 					if (!*p) goto fmt_fail;
216 					if (*p=='-' && p[1] && p[1] != ']')
217 						for (c=p++[-1]; c<*p; c++)
218 							scanset[1+c] = 1-invert;
219 					scanset[1+*p] = 1-invert;
220 				}
221 			}
222 			wcs = 0;
223 			s = 0;
224 			i = 0;
225 			k = t=='c' ? width+1U : 31;
226 			if (size == SIZE_l) {
227 				if (alloc) {
228 					wcs = malloc(k*sizeof(wchar_t));
229 					if (!wcs) goto alloc_fail;
230 				} else {
231 					wcs = dest;
232 				}
233 				st = (mbstate_t){0};
234 				while (scanset[(c=shgetc(f))+1]) {
235 					switch (mbrtowc(&wc, &(char){c}, 1, &st)) {
236 					case -1:
237 						goto input_fail;
238 					case -2:
239 						continue;
240 					}
241 					if (wcs) wcs[i++] = wc;
242 					if (alloc && i==k) {
243 						k+=k+1;
244 						wchar_t *tmp = realloc(wcs, k*sizeof(wchar_t));
245 						if (!tmp) goto alloc_fail;
246 						wcs = tmp;
247 					}
248 				}
249 				if (!mbsinit(&st)) goto input_fail;
250 			} else if (alloc) {
251 				s = malloc(k);
252 				if (!s) goto alloc_fail;
253 				while (scanset[(c=shgetc(f))+1]) {
254 					s[i++] = c;
255 					if (i==k) {
256 						k+=k+1;
257 						char *tmp = realloc(s, k);
258 						if (!tmp) goto alloc_fail;
259 						s = tmp;
260 					}
261 				}
262 			} else if ((s = dest)) {
263 				while (scanset[(c=shgetc(f))+1])
264 					s[i++] = c;
265 			} else {
266 				while (scanset[(c=shgetc(f))+1]);
267 			}
268 			shunget(f);
269 			if (!shcnt(f)) goto match_fail;
270 			if (t == 'c' && shcnt(f) != width) goto match_fail;
271 			if (alloc) {
272 				if (size == SIZE_l) *(wchar_t **)dest = wcs;
273 				else *(char **)dest = s;
274 			}
275 			if (t != 'c') {
276 				if (wcs) wcs[i] = 0;
277 				if (s) s[i] = 0;
278 			}
279 			break;
280 		case 'p':
281 		case 'X':
282 		case 'x':
283 			base = 16;
284 			goto int_common;
285 		case 'o':
286 			base = 8;
287 			goto int_common;
288 		case 'd':
289 		case 'u':
290 			base = 10;
291 			goto int_common;
292 		case 'i':
293 			base = 0;
294 		int_common:
295 			x = __intscan(f, base, 0, ULLONG_MAX);
296 			if (!shcnt(f)) goto match_fail;
297 			if (t=='p' && dest) *(void **)dest = (void *)(uintptr_t)x;
298 			else store_int(dest, size, x);
299 			break;
300 		case 'a': case 'A':
301 		case 'e': case 'E':
302 		case 'f': case 'F':
303 		case 'g': case 'G':
304 #if !WITH_NO_FP
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 #else
319 			fputs("Floating point code is not supported\n", stderr);
320 			abort();
321 #endif
322 			break;
323 		}
324 
325 		pos += shcnt(f);
326 		if (dest) matches++;
327 	}
328 	if (0) {
329 fmt_fail:
330 alloc_fail:
331 input_fail:
332 		if (!matches) matches--;
333 match_fail:
334 		if (alloc) {
335 			free(s);
336 			free(wcs);
337 		}
338 	}
339 	FUNLOCK(f);
340 	return matches;
341 }
342 
343 weak_alias(vfscanf,__isoc99_vfscanf);
344