Subversion Repositories SvarDOS

/* translates a version string into a array of integer values. The array must be 8-position long.

   returns 0 if parsing was successful, non-zero otherwise.

   Accepted formats follow:

    300.12.1

    1

    12.2.34.2-4.5

    1.2c

    1.01

    2013-12-31   */

static int versiontointarr(char *verstr, int *arr) {

  int i, vlen, dotcounter = 1, firstcharaftersep = 0;

  char *digits[8];

  char verstrcopy[16];

  /* fill the array with zeroes first */

  for (i = 0; i < 8; i++) arr[i] = 0;

  /* first extensively validate the input */

  if (verstr == NULL) return(-1);

  vlen = strlen(verstr);

  if (vlen == 0) return(-1);

  if (vlen > 15) return(-1);

  if ((verstr[0] < '0') || (verstr[0] > '9')) return(-1); /* a version string must start with a 0..9 digit */

  if ((tolower(verstr[vlen - 1]) >= 'a') && (tolower(verstr[vlen - 1]) <= 'z') && (vlen > 1)) { /* remove any letter from the end, and use it as a (very) minor differenciator */

    vlen -= 1;

    arr[7] = tolower(verstr[vlen]);

  }

  if ((verstr[vlen - 1] < '0') || (verstr[vlen - 1] > '9')) return(-1); /* a version string must end with a 0..9 digit */

  digits[0] = verstrcopy;

  for (i = 0; i < vlen; i++) {

    verstrcopy[i] = verstr[i];

    switch (verstr[i]) {

      case '.':

      case '-':

        if (i == 0) return(-1);

        if (verstrcopy[i-1] == 0) return(-1); /* do not allow two separators in a row */

        if (dotcounter > 6) return(-1);

        digits[dotcounter++] = &verstrcopy[i + 1];

        verstrcopy[i] = 0;

        firstcharaftersep = 1;

        break;

      case '0':

        /* if this is a zero right after a separator, and trailed with a digit

         * (as in '1.01'), then enforce a separator first */

        if ((firstcharaftersep != 0) && (verstr[i+1] >= '0') && (verstr[i+1] <= '9')) {

          if (dotcounter > 6) return(-1);

          digits[dotcounter++] = &verstrcopy[i + 1];

          verstrcopy[i] = 0;

        }

        break;

      case '1':

      case '2':

      case '3':

      case '4':

      case '5':

      case '6':

      case '7':

      case '8':

      case '9':

        firstcharaftersep = 0;

        break;

      default: /* do not allow any character different than 0..9 or '.' */

        return(-1);

        break;

    }

  }

  verstrcopy[i] = 0;

  /* now that we know the input is sane, let's process it */

  for (i = 0; i < dotcounter; i++) {

    int tmpint;

    tmpint = atoi(digits[i]);

    if ((tmpint < 0) || (tmpint > 32000)) return(-1);

    arr[i] = tmpint;

  }

  return(0);

}

/* compares version strings v1 and v2. Returns 1 if v2 is newer than v1, 0 otherwise, and -1 if comparison is unable to tell */

int isversionnewer(char *v1, char *v2) {

  int x1[8], x2[8], i;

  if ((v1 == NULL) || (v2 == NULL)) return(-1); /* if input is invalid (NULL), don't continue */

  if (strcasecmp(v1, v2) == 0) return(0);  /* if both versions are the same, don't continue */

  /* check versions of the decimal format 1.23... */

  if ((versiontointarr(v1, x1) != 0) || (versiontointarr(v2, x2) != 0)) return(-1);

  for (i = 0; i < 8; i++) {

    if (x2[i] > x1[i]) return(1);

    if (x2[i] < x1[i]) return(0);

  }

  return(0);

}