libc/stdio/doscanf.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2008  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 #include <_printf.h> /* fnptr_t */
  21 #include <string.h> /* strlen() */
  22 #include <stdarg.h> /* va_list, va_arg() */
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25
  26 static int scanf_getint (int *n)
  27 {
  28         char *str = (char *) malloc (sizeof (char) * 128);
  29
  30         if (!str)
  31                 return 0;
  32
  33         unsigned i = 0;
  34
  35         while (1) {
  36                 schedule ();
  37
  38                 char c = getch ();
  39
  40                 if (!c)
  41                         continue;
  42
  43                 if (c == '\n' || i > 127)
  44                         break;
  45
  46                 putch (c);
  47
  48                 if (c == ' ' && i)
  49                         break;
  50
  51                 str[i] = c;
  52
  53                 if (c == '\b' && i)
  54                         i --;
  55                 else
  56                         i ++;
  57         }
  58
  59         if (!i)
  60                 return 0;
  61
  62         str[i] = '\0';
  63
  64         i = 0;
  65
  66         *n = atoi (str);
  67
  68         free (str);
  69
  70         return 1;
  71 }
  72
  73 /* TODO: implement real floatint point format */
  74 static int scanf_getfloat (float *n)
  75 {
  76         char *str = (char *) malloc (sizeof (char) * 128);
  77
  78         if (!str)
  79                 return 0;
  80
  81         unsigned i = 0;
  82
  83         while (1) {
  84                 schedule ();
  85
  86                 char c = getch ();
  87
  88                 if (!c)
  89                         continue;
  90
  91                 if (c == '\n' || i > 127)
  92                         break;
  93
  94                 putch (c);
  95
  96                 if (c == ' ' && i)
  97                         break;
  98
  99                 str[i] = c;
 100
 101                 if (c == '\b' && i)
 102                         i --;
 103                 else
 104                         i ++;
 105         }
 106
 107         if (!i)
 108                 return 0;
 109
 110         str[i] = '\0';
 111
 112         i = 0;
 113
 114         *n = (float) atoi (str);
 115
 116         free (str);
 117
 118         return 1;
 119 }
 120
 121 static int scanf_gethex (int *n)
 122 {
 123         char *str = (char *) malloc (sizeof (char) * 128);
 124
 125         if (!str)
 126                 return 0;
 127
 128         unsigned i = 0;
 129
 130         while (1) {
 131                 schedule ();
 132
 133                 char c = getch ();
 134
 135                 if (!c)
 136                         continue;
 137
 138                 if (c == '\n' || i > 127)
 139                         break;
 140
 141                 putch (c);
 142
 143                 if (c == ' ' && i)
 144                         break;
 145
 146                 str[i] = c;
 147
 148                 if (c == '\b' && i)
 149                         i --;
 150                 else
 151                         i ++;
 152         }
 153
 154         if (!i)
 155                 return 0;
 156
 157         str[i] = '\0';
 158
 159         i = 0;
 160
 161         char *endptr;
 162
 163         *n = strtol (str, &endptr, 16);
 164
 165         free (str);
 166
 167         return 1;
 168 }
 169
 170 static int scanf_getstring (unsigned char *n)
 171 {
 172         unsigned i = 0;
 173
 174         while (1) {
 175                 schedule ();
 176
 177                 char c = getch ();
 178
 179                 if (!c)
 180                         continue;
 181
 182                 if (c == '\n')
 183                         break;
 184
 185                 putch (c);
 186
 187                 if (c == ' ' && i)
 188                         break;
 189
 190                 n[i] = c;
 191
 192                 if (c == '\b' && i)
 193                         i --;
 194                 else
 195                         i ++;
 196         }
 197
 198         if (!i)
 199                 return 0;
 200
 201         n[i] = '\0';
 202
 203         return 1;
 204 }
 205
 206 static int scanf_getchar (unsigned char *n)
 207 {
 208         unsigned i = 0;
 209
 210         while (1) {
 211                 schedule ();
 212
 213                 char c = getch ();
 214
 215                 if (!c)
 216                         continue;
 217
 218                 if (c == '\n')
 219                         break;
 220
 221                 putch (c);
 222
 223                 if (c == ' ' && i)
 224                         break;
 225
 226                 if (i == 0)
 227                         n[i] = c;
 228
 229                 if (c == '\b' && i)
 230                         i --;
 231                 else
 232                         i ++;
 233         }
 234
 235         if (!i)
 236                 return 0;
 237
 238         return 1;
 239 }
 240
 241 int do_scanf (const char *fmt, va_list args)
 242 {
 243         unsigned count = 0;
 244         int *num = 0;
 245         float *fp = 0;
 246         unsigned char *buf = 0;
 247
 248         for (; *fmt; fmt ++) {
 249                 /* probably argument is here */
 250                 if (*fmt == '%') {
 251                         fmt ++;
 252
 253                         if (!*fmt)
 254                                 break;
 255
 256                         if (*fmt == 'd' || *fmt == 'i' || *fmt == 'u') {
 257                                 num = va_arg (args, int *);
 258
 259                                 if (scanf_getint (num))
 260                                         count ++;
 261
 262                                 continue;
 263                         }
 264
 265                         if (*fmt == 'x' || *fmt == 'X') {
 266                                 num = va_arg (args, int *);
 267
 268                                 if (scanf_gethex (num))
 269                                         count ++;
 270
 271                                 continue;
 272                         }
 273
 274                         if (*fmt == 'c') {
 275                                 buf = va_arg (args, unsigned char *);
 276
 277                                 if (scanf_getchar (buf))
 278                                         count ++;
 279
 280                                 continue;
 281                         }
 282
 283                         if (*fmt == 'f') {
 284                                 fp = va_arg (args, float *);
 285
 286                                 if (scanf_getfloat (fp))
 287                                         count ++;
 288
 289                                 continue;
 290                         }
 291
 292                         if (*fmt == 's') {
 293                                 buf = va_arg (args, unsigned char *);
 294
 295                                 if (scanf_getstring (buf))
 296                                         count ++;
 297
 298                                 continue;
 299                         }
 300
 301                         continue;
 302                 }
 303
 304                 count ++;
 305
 306         }
 307
 308         return count;
 309 }
 310