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