contrib/top/getopt.c

   1 /*
   2  * "getopt" routine customized for top.
   3  */
   4
   5 /*
   6  * Many modern-day Unix implementations already have this function
   7  * in libc.  The standard "getopt" is perfectly sufficient for top's
   8  * needs.  If such a function exists in libc then you certainly don't
   9  * need to compile this one in.  To prevent this function from being
  10  * compiled, define "HAVE_GETOPT".  This is usually done in the "CFLAGS"
  11  * line of the corresponding machine module.
  12  */
  13
  14 /*
  15  * This empty declaration exists solely to placate overexhuberant C
  16  * compilers that like to warn you about content-free files.
  17  */
  18 static void __empty();
  19
  20 #ifndef HAVE_GETOPT
  21
  22 /*LINTLIBRARY*/
  23
  24 #include "os.h"
  25 #ifndef NULL
  26 #define NULL    0
  27 #endif
  28 #ifndef EOF
  29 #define EOF     (-1)
  30 #endif
  31 #define ERR(s, c)       if(opterr){\
  32         extern int write();\
  33         char errbuf[2];\
  34         errbuf[0] = c; errbuf[1] = '\n';\
  35         (void) write(2, argv[0], strlen(argv[0]));\
  36         (void) write(2, s, strlen(s));\
  37         (void) write(2, errbuf, 2);}
  38
  39
  40 int     opterr = 1;
  41 int     optind = 1;
  42 int     optopt;
  43 char    *optarg;
  44
  45 int
  46 getopt(argc, argv, opts)
  47 int     argc;
  48 char    **argv, *opts;
  49 {
  50         static int sp = 1;
  51         register int c;
  52         register char *cp;
  53
  54         if(sp == 1)
  55                 if(optind >= argc ||
  56                    argv[optind][0] != '-' || argv[optind][1] == '\0')
  57                         return(EOF);
  58                 else if(strcmp(argv[optind], "--") == 0) {
  59                         optind++;
  60                         return(EOF);
  61                 }
  62         optopt = c = argv[optind][sp];
  63         if(c == ':' || (cp=strchr(opts, c)) == NULL) {
  64                 ERR(": unknown option, -", c);
  65                 if(argv[optind][++sp] == '\0') {
  66                         optind++;
  67                         sp = 1;
  68                 }
  69                 return('?');
  70         }
  71         if(*++cp == ':') {
  72                 if(argv[optind][sp+1] != '\0')
  73                         optarg = &argv[optind++][sp+1];
  74                 else if(++optind >= argc) {
  75                         ERR(": argument missing for -", c);
  76                         sp = 1;
  77                         return('?');
  78                 } else
  79                         optarg = argv[optind++];
  80                 sp = 1;
  81         } else {
  82                 if(argv[optind][++sp] == '\0') {
  83                         sp = 1;
  84                         optind++;
  85                 }
  86                 optarg = NULL;
  87         }
  88         return(c);
  89 }
  90 #endif /* HAVE_GETOPT */