src/stdio/vfscanf.c

   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;
  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         for (p=(const unsigned char *)fmt; *p; p++) {
  80
  81                 alloc = 0;
  82
  83                 if (isspace(*p)) {
  84                         while (isspace(p[1])) p++;
  85                         shlim(f, 0);
  86                         while (isspace(shgetc(f)));
  87                         shunget(f);
  88                         pos += shcnt(f);
  89                         continue;
  90                 }
  91                 if (*p != '%' || p[1] == '%') {
  92                         p += *p=='%';
  93                         shlim(f, 0);
  94                         c = shgetc(f);
  95                         if (c!=*p) {
  96                                 shunget(f);
  97                                 if (c<0) goto input_fail;
  98                                 goto match_fail;
  99                         }
 100                         pos++;
 101                         continue;
 102                 }
 103
 104                 p++;
 105                 if (*p=='*') {
 106                         dest = 0; p++;
 107                 } else if (isdigit(*p) && p[1]=='$') {
 108                         dest = arg_n(ap, *p-'0'); p+=2;
 109                 } else {
 110                         dest = va_arg(ap, void *);
 111                 }
 112
 113                 for (width=0; isdigit(*p); p++) {
 114                         width = 10*width + *p - '0';
 115                 }
 116
 117                 if (*p=='m') {
 118                         wcs = 0;
 119                         s = 0;
 120                         alloc = !!dest;
 121                         p++;
 122                 } else {
 123                         alloc = 0;
 124                 }
 125
 126                 size = SIZE_def;
 127                 switch (*p++) {
 128                 case 'h':
 129                         if (*p == 'h') p++, size = SIZE_hh;
 130                         else size = SIZE_h;
 131                         break;
 132                 case 'l':
 133                         if (*p == 'l') p++, size = SIZE_ll;
 134                         else size = SIZE_l;
 135                         break;
 136                 case 'j':
 137                         size = SIZE_ll;
 138                         break;
 139                 case 'z':
 140                 case 't':
 141                         size = SIZE_l;
 142                         break;
 143                 case 'L':
 144                         size = SIZE_L;
 145                         break;
 146                 case 'd': case 'i': case 'o': case 'u': case 'x':
 147                 case 'a': case 'e': case 'f': case 'g':
 148                 case 'A': case 'E': case 'F': case 'G': case 'X':
 149                 case 's': case 'c': case '[':
 150                 case 'S': case 'C':
 151                 case 'p': case 'n':
 152                         p--;
 153                         break;
 154                 default:
 155                         goto fmt_fail;
 156                 }
 157
 158                 t = *p;
 159
 160                 /* C or S */
 161                 if ((t&0x2f) == 3) {
 162                         t |= 32;
 163                         size = SIZE_l;
 164                 }
 165
 166                 switch (t) {
 167                 case 'c':
 168                         if (width < 1) width = 1;
 169                 case '[':
 170                         break;
 171                 case 'n':
 172                         store_int(dest, size, pos);
 173                         /* do not increment match count, etc! */
 174                         continue;
 175                 default:
 176                         shlim(f, 0);
 177                         while (isspace(shgetc(f)));
 178                         shunget(f);
 179                         pos += shcnt(f);
 180                 }
 181
 182                 shlim(f, width);
 183                 if (shgetc(f) < 0) goto input_fail;
 184                 shunget(f);
 185
 186                 switch (t) {
 187                 case 's':
 188                 case 'c':
 189                 case '[':
 190                         if (t == 'c' || t == 's') {
 191                                 memset(scanset, -1, sizeof scanset);
 192                                 scanset[0] = 0;
 193                                 if (t == 's') {
 194                                         scanset[1+'\t'] = 0;
 195                                         scanset[1+'\n'] = 0;
 196                                         scanset[1+'\v'] = 0;
 197                                         scanset[1+'\f'] = 0;
 198                                         scanset[1+'\r'] = 0;
 199                                         scanset[1+' '] = 0;
 200                                 }
 201                         } else {
 202                                 if (*++p == '^') p++, invert = 1;
 203                                 else invert = 0;
 204                                 memset(scanset, invert, sizeof scanset);
 205                                 scanset[0] = 0;
 206                                 if (*p == '-') p++, scanset[1+'-'] = 1-invert;
 207                                 else if (*p == ']') p++, scanset[1+']'] = 1-invert;
 208                                 for (; *p != ']'; p++) {
 209                                         if (!*p) goto fmt_fail;
 210                                         if (*p=='-' && p[1] && p[1] != ']')
 211                                                 for (c=p++[-1]; c<*p; c++)
 212                                                         scanset[1+c] = 1-invert;
 213                                         scanset[1+*p] = 1-invert;
 214                                 }
 215                         }
 216                         wcs = 0;
 217                         s = 0;
 218                         i = 0;
 219                         k = t=='c' ? width+1U : 31;
 220                         if (size == SIZE_l) {
 221                                 if (alloc) {
 222                                         wcs = malloc(k*sizeof(wchar_t));
 223                                         if (!wcs) goto alloc_fail;
 224                                 } else {
 225                                         wcs = dest;
 226                                 }
 227                                 st = (mbstate_t){0};
 228                                 while (scanset[(c=shgetc(f))+1]) {
 229                                         switch (mbrtowc(&wc, &(char){c}, 1, &st)) {
 230                                         case -1:
 231                                                 goto input_fail;
 232                                         case -2:
 233                                                 continue;
 234                                         }
 235                                         if (wcs) wcs[i++] = wc;
 236                                         if (alloc && i==k) {
 237                                                 k+=k+1;
 238                                                 wchar_t *tmp = realloc(wcs, k*sizeof(wchar_t));
 239                                                 if (!tmp) goto alloc_fail;
 240                                                 wcs = tmp;
 241                                         }
 242                                 }
 243                                 if (!mbsinit(&st)) goto input_fail;
 244                         } else if (alloc) {
 245                                 s = malloc(k);
 246                                 if (!s) goto alloc_fail;
 247                                 while (scanset[(c=shgetc(f))+1]) {
 248                                         s[i++] = c;
 249                                         if (i==k) {
 250                                                 k+=k+1;
 251                                                 char *tmp = realloc(s, k);
 252                                                 if (!tmp) goto alloc_fail;
 253                                                 s = tmp;
 254                                         }
 255                                 }
 256                         } else if ((s = dest)) {
 257                                 while (scanset[(c=shgetc(f))+1])
 258                                         s[i++] = c;
 259                         } else {
 260                                 while (scanset[(c=shgetc(f))+1]);
 261                         }
 262                         shunget(f);
 263                         if (!shcnt(f)) goto match_fail;
 264                         if (t == 'c' && shcnt(f) != width) goto match_fail;
 265                         if (alloc) {
 266                                 if (size == SIZE_l) *(wchar_t **)dest = wcs;
 267                                 else *(char **)dest = s;
 268                         }
 269                         if (t != 'c') {
 270                                 if (wcs) wcs[i] = 0;
 271                                 if (s) s[i] = 0;
 272                         }
 273                         break;
 274                 case 'p':
 275                 case 'X':
 276                 case 'x':
 277                         base = 16;
 278                         goto int_common;
 279                 case 'o':
 280                         base = 8;
 281                         goto int_common;
 282                 case 'd':
 283                 case 'u':
 284                         base = 10;
 285                         goto int_common;
 286                 case 'i':
 287                         base = 0;
 288                 int_common:
 289                         x = __intscan(f, base, 0, ULLONG_MAX);
 290                         if (!shcnt(f)) goto match_fail;
 291                         if (t=='p' && dest) *(void **)dest = (void *)(uintptr_t)x;
 292                         else store_int(dest, size, x);
 293                         break;
 294                 case 'a': case 'A':
 295                 case 'e': case 'E':
 296                 case 'f': case 'F':
 297                 case 'g': case 'G':
 298                         y = __floatscan(f, size, 0);
 299                         if (!shcnt(f)) goto match_fail;
 300                         if (dest) switch (size) {
 301                         case SIZE_def:
 302                                 *(float *)dest = y;
 303                                 break;
 304                         case SIZE_l:
 305                                 *(double *)dest = y;
 306                                 break;
 307                         case SIZE_L:
 308                                 *(long double *)dest = y;
 309                                 break;
 310                         }
 311                         break;
 312                 }
 313
 314                 pos += shcnt(f);
 315                 if (dest) matches++;
 316         }
 317         if (0) {
 318 fmt_fail:
 319 alloc_fail:
 320 input_fail:
 321                 if (!matches) matches--;
 322 match_fail:
 323                 if (alloc) {
 324                         free(s);
 325                         free(wcs);
 326                 }
 327         }
 328         FUNLOCK(f);
 329         return matches;
 330 }
 331
 332 weak_alias(vfscanf,__isoc99_vfscanf);