libc/stdio/doprintf.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2007  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   4  *  Copyright (C) 2008  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   5  *
   6  *  This program is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20
  21 #include <_printf.h> /* fnptr_t */
  22 #include <string.h> /* strlen() */
  23 #include <stdarg.h> /* va_list, va_arg() */
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26
  27 int do_printf (const char *fmt, va_list args)
  28 {
  29         unsigned i = 0;
  30         unsigned count = 0;
  31         long num = 0;
  32         char str[16];
  33         unsigned char *buf = 0;
  34
  35         for (; *fmt; fmt ++) {
  36                 /* probably argument is here */
  37                 if (*fmt == '%') {
  38                         fmt ++;
  39
  40                         if (!*fmt)
  41                                 break;
  42
  43                         if (*fmt == 'd' || *fmt == 'i' || *fmt == 'u') {
  44                                 num = va_arg (args, int);
  45
  46                                 itoa (num, str, 10);
  47
  48                                 for (i = 0; str[i]; i ++)
  49                                         putch (str[i]);
  50
  51                                 count += i;
  52
  53                                 continue;
  54                         }
  55
  56                         if (*fmt == 'f') {
  57                                 num = va_arg (args, double);
  58
  59                                 int f;
  60
  61                                 if (num >= 1)
  62                                         f = (int) num;
  63                                 else {
  64                                         count += 2;
  65
  66                                         putch ('0');
  67                                         putch ('.');
  68
  69                                         f = (int) ((double) num * (double) 10000);
  70                                 }
  71
  72                                 itoa (f, str, 10);
  73
  74                                 for (i = 0; str[i]; i ++)
  75                                         putch (str[i]);
  76
  77                                 count += i;
  78
  79                                 continue;
  80                         }
  81
  82                         if (*fmt == 'x' || *fmt == 'X') {
  83                                 num = va_arg (args, int);
  84
  85                                 itoa (num, str, 16);
  86
  87                                 for (i = 0; str[i]; i ++)
  88                                         putch (str[i]);
  89
  90                                 count += i;
  91
  92                                 continue;
  93                         }
  94
  95                         if (*fmt == 'c') {
  96                                 num = va_arg (args, unsigned char);
  97
  98                                 putch ((unsigned char) num);
  99
 100                                 count ++;
 101
 102                                 continue;
 103                         }
 104
 105                         if (*fmt == 's') {
 106                                 buf = va_arg (args, unsigned char *);
 107
 108                                 for (i = 0; buf[i]; i ++)
 109                                         putch ((unsigned char) buf[i]);
 110
 111                                 count += i;
 112
 113                                 continue;
 114                         }
 115
 116                         continue;
 117                 }
 118
 119                 putch (*fmt);
 120                 count ++;
 121
 122         }
 123
 124         return count;
 125 }
 126
 127 int do_sprintf (const char *fmt, va_list args, char *ptr)
 128 {
 129         unsigned i = 0;
 130         unsigned count = 0;
 131         long num = 0;
 132         char str[16];
 133         unsigned char *buf = 0;
 134
 135         for (; *fmt; fmt ++) {
 136                 /* probably argument is here */
 137                 if (*fmt == '%') {
 138                         fmt ++;
 139
 140                         if (!*fmt)
 141                                 break;
 142
 143                         if (*fmt == 'd' || *fmt == 'i' || *fmt == 'u') {
 144                                 num = va_arg (args, int);
 145
 146                                 itoa (num, str, 10);
 147
 148                                 for (i = 0; str[i]; i ++)
 149                                         ptr[i+count] = str[i];
 150
 151                                 count += i;
 152
 153                                 continue;
 154                         }
 155
 156                         if (*fmt == 'x' || *fmt == 'X') {
 157                                 num = va_arg (args, int);
 158
 159                                 itoa (num, str, 16);
 160
 161                                 for (i = 0; str[i]; i ++)
 162                                         ptr[i+count] = str[i];
 163
 164                                 count += i;
 165
 166                                 continue;
 167                         }
 168
 169                         if (*fmt == 'c') {
 170                                 num = va_arg (args, unsigned char);
 171
 172                                 ptr[count] = (unsigned char) num;
 173
 174                                 count ++;
 175
 176                                 continue;
 177                         }
 178
 179                         if (*fmt == 's') {
 180                                 buf = va_arg (args, unsigned char *);
 181
 182                                 for (i = 0; buf[i]; i ++)
 183                                         ptr[i+count] = buf[i];
 184
 185                                 count += i;
 186
 187                                 continue;
 188                         }
 189
 190                         continue;
 191                 }
 192
 193                 ptr[count] = *fmt;
 194                 count ++;
 195
 196         }
 197
 198         return count;
 199 }
 200
 201 /*****************************************************************************
 202 SPRINTF
 203 *****************************************************************************/
 204
 205 int vsprintf (char *buffer, const char *fmt, va_list args)
 206 {
 207         int ret_val;
 208
 209         ret_val = do_sprintf (fmt, args, (char *) buffer);
 210         buffer[ret_val] = '\0';
 211         return ret_val;
 212 }
 213
 214 #if 0 /* testing */
 215 /*****************************************************************************
 216 *****************************************************************************/
 217 int sprintf(char *buffer, const char *fmt, ...)
 218 {
 219         va_list args;
 220         int ret_val;
 221
 222         va_start(args, fmt);
 223         ret_val = vsprintf(buffer, fmt, args);
 224         va_end(args);
 225         return ret_val;
 226 }
 227 /*****************************************************************************
 228 PRINTF
 229 You must write your own putchar()
 230 *****************************************************************************/
 231 int vprintf_help(unsigned c, void **ptr)
 232 {
 233         putchar(c);
 234         return 0 ;
 235 }
 236 /*****************************************************************************
 237 *****************************************************************************/
 238 int vprintf(const char *fmt, va_list args)
 239 {
 240         return do_printf(fmt, args, vprintf_help, NULL);
 241 }
 242 /*****************************************************************************
 243 *****************************************************************************/
 244 int printf(const char *fmt, ...)
 245 {
 246         va_list args;
 247         int ret_val;
 248
 249         va_start(args, fmt);
 250         ret_val = vprintf(fmt, args);
 251         va_end(args);
 252         return ret_val;
 253 }
 254 /*****************************************************************************
 255 *****************************************************************************/
 256 int main(void)
 257 {
 258         char buf[64];
 259
 260         sprintf(buf, "%u score and %i years ago...\n", 4, -7);
 261         puts(buf);
 262
 263         sprintf(buf, "-1L == 0x%lX == octal %lo\n", -1L, -1L);
 264         puts(buf);
 265
 266         printf("<%-08s> and <%08s> justified strings\n", "left", "right");
 267         return 0;
 268 }
 269 #endif