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Member "ngrep-1_47/win32/support/getopt.c" (7 Sep 2017, 4687 Bytes) of package /linux/misc/ngrep-1_47.tar.gz:

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    1 
    2 #include <stdio.h>                  /* for EOF */ 
    3 #include <string.h>                 /* for strchr() */ 
    4 
    5 #include <getopt.h> 
    6  
    7 /* static (global) variables that are specified as exported by getopt() */ 
    8 char *optarg = NULL;    /* pointer to the start of the option argument  */ 
    9 int   optind = 1;       /* number of the next argv[] to be evaluated    */ 
   10 int   opterr = 1;       /* non-zero if a question mark should be returned 
   11                            when a non-valid option character is detected */
   12 
   13 int getopt(int argc, char *argv[], char *opstring) { 
   14   static char *pIndexPosition = NULL; /* place inside current argv string */ 
   15   char *pArgString = NULL;        /* where to start from next */ 
   16   char *pOptString;               /* the string in our program */ 
   17  
   18   if (pIndexPosition != NULL) { 
   19     /* we last left off inside an argv string */ 
   20     if (*(++pIndexPosition)) { 
   21       /* there is more to come in the most recent argv */ 
   22       pArgString = pIndexPosition; 
   23     } 
   24   } 
   25  
   26   if (pArgString == NULL) { 
   27     /* we didn't leave off in the middle of an argv string */ 
   28     if (optind >= argc) { 
   29       /* more command-line arguments than the argument count */ 
   30       pIndexPosition = NULL;  /* not in the middle of anything */ 
   31       return EOF;             /* used up all command-line arguments */ 
   32     } 
   33  
   34     /*--------------------------------------------------------------------- 
   35      * If the next argv[] is not an option, there can be no more options. 
   36      *-------------------------------------------------------------------*/ 
   37     pArgString = argv[optind++]; /* set this to the next argument ptr */ 
   38  
   39     if (('/' != *pArgString) && /* doesn't start with a slash or a dash? */ 
   40     ('-' != *pArgString)) { 
   41       --optind;               /* point to current arg once we're done */ 
   42       optarg = NULL;          /* no argument follows the option */ 
   43       pIndexPosition = NULL;  /* not in the middle of anything */ 
   44       return EOF;             /* used up all the command-line flags */ 
   45     } 
   46 
   47     /* check for special end-of-flags markers */ 
   48     if ((strcmp(pArgString, "-") == 0) || 
   49     (strcmp(pArgString, "--") == 0)) { 
   50       optarg = NULL;          /* no argument follows the option */ 
   51       pIndexPosition = NULL;  /* not in the middle of anything */ 
   52       return EOF;             /* encountered the special flag */ 
   53     } 
   54  
   55     pArgString++;               /* look past the / or - */ 
   56   } 
   57  
   58   if (':' == *pArgString) {       /* is it a colon? */ 
   59     /*--------------------------------------------------------------------- 
   60      * Rare case: if opterr is non-zero, return a question mark; 
   61      * otherwise, just return the colon we're on. 
   62      *-------------------------------------------------------------------*/ 
   63     return (opterr ? (int)'?' : (int)':'); 
   64   } else if ((pOptString = strchr(opstring, *pArgString)) == 0) { 
   65     /*--------------------------------------------------------------------- 
   66      * The letter on the command-line wasn't any good. 
   67      *-------------------------------------------------------------------*/ 
   68     optarg = NULL;              /* no argument follows the option */ 
   69     pIndexPosition = NULL;      /* not in the middle of anything */ 
   70     return (opterr ? (int)'?' : (int)*pArgString); 
   71   } else { 
   72     /*--------------------------------------------------------------------- 
   73      * The letter on the command-line matches one we expect to see 
   74      *-------------------------------------------------------------------*/ 
   75     if (':' == _next_char(pOptString)) { /* is the next letter a colon? */ 
   76       /* It is a colon.  Look for an argument string. */ 
   77       if ('\0' != _next_char(pArgString))  /* argument in this argv? */ 
   78     optarg = &pArgString[1];   /* Yes, it is */ 
   79       else { 
   80     /*------------------------------------------------------------- 
   81      * The argument string must be in the next argv. 
   82      * But, what if there is none (bad input from the user)? 
   83      * In that case, return the letter, and optarg as NULL. 
   84      *-----------------------------------------------------------*/ 
   85     if (optind < argc) 
   86       optarg = argv[optind++]; 
   87     else { 
   88       optarg = NULL; 
   89       return (opterr ? (int)'?' : (int)*pArgString); 
   90     } 
   91       } 
   92 
   93       pIndexPosition = NULL;  /* not in the middle of anything */ 
   94     } else { 
   95       /* it's not a colon, so just return the letter */ 
   96       optarg = NULL;          /* no argument follows the option */ 
   97       pIndexPosition = pArgString;    /* point to the letter we're on */ 
   98     } 
   99     return (int)*pArgString;    /* return the letter that matched */ 
  100   } 
  101 }