FreeCalypso > hg > freecalypso-sw
annotate miscutil/imei-luhn.c @ 949:df1dccc0ef9c
c139explore: GPIO init and backlight on/off control implemented
author | Mychaela Falconia <falcon@ivan.Harhan.ORG> |
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date | Wed, 04 Nov 2015 00:46:36 +0000 |
parents | cd043e690621 |
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rev | line source |
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271
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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1 /* |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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2 * This program computes the Luhn check digit for an IMEI number given |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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3 * the first 14 digits, or verifies the correctness of this check digit |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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4 * given a 15-digit number as input. |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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5 * |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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6 * The number given on the command line may optionally include punctuation, |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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7 * which is skipped and ignored. |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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8 */ |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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9 |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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10 #include <stdio.h> |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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11 #include <ctype.h> |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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12 #include <stdlib.h> |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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13 |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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14 char digits[15]; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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15 |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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16 compute_cd() |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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17 { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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18 int i, dig, sum; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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19 |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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20 sum = 0; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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21 for (i = 0; i < 14; i++) { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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22 dig = digits[i]; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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23 if (i & 1) { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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24 dig *= 2; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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25 if (dig > 9) |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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26 dig -= 9; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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27 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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28 sum += dig; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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29 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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30 dig = sum % 10; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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31 if (dig) |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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32 dig = 10 - dig; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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33 return dig; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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34 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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35 |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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36 main(argc, argv) |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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37 char **argv; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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38 { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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39 char *cp; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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40 int i; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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41 |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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42 if (argc != 2) { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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43 usage: fprintf(stderr, "usage: %s number\n", argv[0]); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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44 exit(2); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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45 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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46 cp = argv[1]; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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47 if (!isdigit(*cp)) |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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48 goto usage; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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49 for (i = 0; *cp; ) { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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50 if (ispunct(*cp)) |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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51 cp++; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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52 if (!isdigit(*cp)) |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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53 goto usage; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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54 if (i >= 15) { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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55 wrong_len: fprintf(stderr, |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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56 "error: argument must have 14 or 15 digits\n"); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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57 exit(2); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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58 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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59 digits[i++] = *cp++ - '0'; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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60 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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61 switch (i) { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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62 case 14: |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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63 printf("%d\n", compute_cd()); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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64 exit(0); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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65 case 15: |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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66 if (digits[14] == compute_cd()) { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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67 printf("IMEI OK\n"); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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68 exit(0); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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69 } else { |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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70 printf("Check digit mismatch!\n"); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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71 exit(1); |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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72 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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73 default: |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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74 goto wrong_len; |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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75 } |
cd043e690621
imei-luhn utility written
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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76 } |