nsz Git - musl/blob - src/stdio/vfscanf.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <stdarg.h>
   4 #include <ctype.h>
   5 #include <wchar.h>
   6 #include <wctype.h>
   7 #include <limits.h>
   8 #include <string.h>
   9 #include <errno.h>
  10 #include <math.h>
  11 #include <float.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 static int readwc(int c, wchar_t **wcs, mbstate_t *st)
  60 {
  61         char ch = c;
  62         wchar_t wc;
  63         switch (mbrtowc(&wc, &ch, 1, st)) {
  64         case -1:
  65                 return -1;
  66         case -2:
  67                 break;
  68         default:
  69                 if (*wcs) *(*wcs)++ = wc;
  70         }
  71         return 0;
  72 }
  73
  74 int vfscanf(FILE *f, const char *fmt, va_list ap)
  75 {
  76         int width;
  77         int size;
  78         int alloc;
  79         int base;
  80         const unsigned char *p;
  81         int c, t;
  82         char *s;
  83         wchar_t *wcs;
  84         mbstate_t st;
  85         void *dest=NULL;
  86         int invert;
  87         int matches=0;
  88         unsigned long long x;
  89         long double y;
  90         off_t pos = 0;
  91
  92         FLOCK(f);
  93
  94         for (p=(const unsigned char *)fmt; *p; p++) {
  95
  96                 if (isspace(*p)) {
  97                         while (isspace(p[1])) p++;
  98                         shlim(f, 0);
  99                         while (isspace(shgetc(f)));
 100                         shunget(f);
 101                         pos += shcnt(f);
 102                         continue;
 103                 }
 104                 if (*p != '%' || p[1] == '%') {
 105                         p += *p=='%';
 106                         c = shgetc(f);
 107                         if (c!=*p) {
 108                                 shunget(f);
 109                                 if (c<0) goto input_fail;
 110                                 goto match_fail;
 111                         }
 112                         pos++;
 113                         continue;
 114                 }
 115
 116                 p++;
 117                 if (*p=='*') {
 118                         dest = 0; p++;
 119                 } else if (isdigit(*p) && p[1]=='$') {
 120                         dest = arg_n(ap, *p-'0'); p+=2;
 121                 } else {
 122                         dest = va_arg(ap, void *);
 123                 }
 124
 125                 for (width=0; isdigit(*p); p++) {
 126                         width = 10*width + *p - '0';
 127                 }
 128
 129                 if (*p=='m') {
 130                         alloc = 1;
 131                         p++;
 132                 } else {
 133                         alloc = 0;
 134                 }
 135
 136                 size = SIZE_def;
 137                 switch (*p++) {
 138                 case 'h':
 139                         if (*p == 'h') p++, size = SIZE_hh;
 140                         else size = SIZE_h;
 141                         break;
 142                 case 'l':
 143                         if (*p == 'l') p++, size = SIZE_ll;
 144                         else size = SIZE_l;
 145                         break;
 146                 case 'j':
 147                         size = SIZE_ll;
 148                         break;
 149                 case 'z':
 150                 case 't':
 151                         size = SIZE_l;
 152                         break;
 153                 case 'L':
 154                         size = SIZE_L;
 155                         break;
 156                 case 'd': case 'i': case 'o': case 'u': case 'x':
 157                 case 'a': case 'e': case 'f': case 'g':
 158                 case 'A': case 'E': case 'F': case 'G': case 'X':
 159                 case 's': case 'c': case '[':
 160                 case 'S': case 'C':
 161                 case 'p': case 'n':
 162                         p--;
 163                         break;
 164                 default:
 165                         goto fmt_fail;
 166                 }
 167
 168                 t = *p;
 169
 170                 switch (t) {
 171                 case 'C':
 172                 case 'c':
 173                         if (width < 1) width = 1;
 174                 case 's':
 175                         if (size == SIZE_l) t &= ~0x20;
 176                 case 'd': case 'i': case 'o': case 'u': case 'x':
 177                 case 'a': case 'e': case 'f': case 'g':
 178                 case 'A': case 'E': case 'F': case 'G': case 'X':
 179                 case '[': case 'S':
 180                 case 'p': case 'n':
 181                         if (width < 1) width = 0;
 182                         break;
 183                 default:
 184                         goto fmt_fail;
 185                 }
 186
 187                 shlim(f, width);
 188
 189                 if (t != 'n') {
 190                         if (shgetc(f) < 0) goto input_fail;
 191                         shunget(f);
 192                 }
 193
 194                 switch (t) {
 195                 case 'n':
 196                         store_int(dest, size, pos);
 197                         /* do not increment match count, etc! */
 198                         continue;
 199                 case 'C':
 200                         wcs = dest;
 201                         st = (mbstate_t){ 0 };
 202                         while ((c=shgetc(f)) >= 0) {
 203                                 if (readwc(c, &wcs, &st) < 0)
 204                                         goto input_fail;
 205                         }
 206                         if (!mbsinit(&st)) goto input_fail;
 207                         if (shcnt(f) != width) goto match_fail;
 208                         break;
 209                 case 'c':
 210                         if (dest) {
 211                                 s = dest;
 212                                 while ((c=shgetc(f)) >= 0) *s++ = c;
 213                         } else {
 214                                 while (shgetc(f)>=0);
 215                         }
 216                         if (shcnt(f) < width) goto match_fail;
 217                         break;
 218                 case '[':
 219                         s = dest;
 220                         wcs = dest;
 221
 222                         if (*++p == '^') p++, invert = 1;
 223                         else invert = 0;
 224
 225                         unsigned char scanset[257];
 226                         memset(scanset, invert, sizeof scanset);
 227
 228                         scanset[0] = 0;
 229                         if (*p == '-') p++, scanset[1+'-'] = 1-invert;
 230                         if (*p == ']') p++, scanset[1+']'] = 1-invert;
 231                         for (; *p && *p != ']'; p++) {
 232                                 if (*p=='-' && p[1] != ']')
 233                                         for (c=p++[-1]; c<*p; c++)
 234                                                 scanset[1+c] = 1-invert;
 235                                 scanset[1+*p] = 1-invert;
 236                         }
 237                         if (!*p) goto fmt_fail;
 238
 239                         if (size == SIZE_l) {
 240                                 st = (mbstate_t){0};
 241                                 while (scanset[(c=shgetc(f))+1]) {
 242                                         if (readwc(c, &wcs, &st) < 0)
 243                                                 goto input_fail;
 244                                 }
 245                                 if (!mbsinit(&st)) goto input_fail;
 246                                 s = 0;
 247                         } else if (s) {
 248                                 while (scanset[(c=shgetc(f))+1])
 249                                         *s++ = c;
 250                                 wcs = 0;
 251                         } else {
 252                                 while (scanset[(c=shgetc(f))+1]);
 253                         }
 254                         shunget(f);
 255                         if (!shcnt(f)) goto match_fail;
 256                         if (s) *s = 0;
 257                         if (wcs) *wcs = 0;
 258                         break;
 259                 default:
 260                         shlim(f, 0);
 261                         while (isspace(shgetc(f)));
 262                         shunget(f);
 263                         pos += shcnt(f);
 264                         shlim(f, width);
 265                         if (shgetc(f) < 0) goto input_fail;
 266                         shunget(f);
 267                 }
 268
 269                 switch (t) {
 270                 case 'p':
 271                 case 'X':
 272                 case 'x':
 273                         base = 16;
 274                         goto int_common;
 275                 case 'o':
 276                         base = 8;
 277                         goto int_common;
 278                 case 'd':
 279                 case 'u':
 280                         base = 10;
 281                         goto int_common;
 282                 case 'i':
 283                         base = 0;
 284                 int_common:
 285                         x = __intscan(f, base, 0, ULLONG_MAX);
 286                         if (!shcnt(f)) goto match_fail;
 287                         if (t=='p' && dest) *(void **)dest = (void *)(uintptr_t)x;
 288                         else store_int(dest, size, x);
 289                         break;
 290                 case 'a': case 'A':
 291                 case 'e': case 'E':
 292                 case 'f': case 'F':
 293                 case 'g': case 'G':
 294                         y = __floatscan(f, -1, size, 0);
 295                         if (!shcnt(f)) goto match_fail;
 296                         if (dest) switch (size) {
 297                         case SIZE_def:
 298                                 *(float *)dest = y;
 299                                 break;
 300                         case SIZE_l:
 301                                 *(double *)dest = y;
 302                                 break;
 303                         case SIZE_L:
 304                                 *(long double *)dest = y;
 305                                 break;
 306                         }
 307                         break;
 308                 case 'S':
 309                         wcs = dest;
 310                         st = (mbstate_t){ 0 };
 311                         while (!isspace(c=shgetc(f)) && c!=EOF) {
 312                                 if (readwc(c, &wcs, &st) < 0)
 313                                         goto input_fail;
 314                         }
 315                         if (!mbsinit(&st)) goto input_fail;
 316                         if (dest) *wcs++ = 0;
 317                         break;
 318                 case 's':
 319                         if (dest) {
 320                                 s = dest;
 321                                 while (!isspace(c=shgetc(f)) && c!=EOF)
 322                                         *s++ = c;
 323                                 *s = 0;
 324                         } else {
 325                                 while (!isspace(c=shgetc(f)) && c!=EOF);
 326                         }
 327                         shunget(f);
 328                         break;
 329                 }
 330
 331                 pos += shcnt(f);
 332                 if (dest) matches++;
 333         }
 334         if (0) {
 335 fmt_fail:
 336 input_fail:
 337                 if (!matches) matches--;
 338         }
 339 match_fail:
 340         FUNLOCK(f);
 341         return matches;
 342 }