commands/basename/basename.c

   1 /* basename - print last part of a path      Authors: B. Garfolo & P. Nelson */
   2
   3 /* Basename - print the last part of a path.
   4  *
   5  *    For MINIX  --  Conforms to POSIX - P1003.2/D10
   6  *      Exception -- it ignores the LC environment variables.
   7  *
   8  *    Original MINIX author:  Blaine Garfolo
   9  *    POSIX rewrite author:   Philip A. Nelson
  10  *
  11  *    POSIX version - October 20, 1990
  12  *      Feb 14, 1991: changed rindex to strrchr. (PAN)
  13  *
  14  */
  15
  16
  17 #include <string.h>
  18 #include <stdlib.h>
  19 #include <stdio.h>
  20
  21 #define EOS '\0'
  22
  23 int main(int argc, char **argv);
  24
  25 int main(argc, argv)
  26 int argc;
  27 char *argv[];
  28 {
  29   char *result_string;          /* The pointer into argv[1]. */
  30   char *temp;                   /* Used to move around in argv[1]. */
  31   int suffix_len;               /* Length of the suffix. */
  32   int suffix_start;             /* Where the suffix should start. */
  33
  34
  35   /* Check for the correct number of arguments. */
  36   if ((argc < 2) || (argc > 3)) {
  37         fprintf(stderr, "Usage: basename string [suffix] \n");
  38         exit(1);
  39   }
  40
  41   /* Check for all /'s */
  42   for (temp = argv[1]; *temp == '/'; temp++)    /* Move to next char. */
  43         ;
  44   if (*temp == EOS) {
  45         printf("/\n");
  46         exit(0);
  47   }
  48
  49   /* Build the basename. */
  50   result_string = argv[1];
  51
  52   /* Find the last /'s */
  53   temp = strrchr(result_string, '/');
  54
  55   if (temp != NULL) {
  56         /* Remove trailing /'s. */
  57         while ((*(temp + 1) == EOS) && (*temp == '/')) *temp-- = EOS;
  58
  59         /* Set result_string to last part of path. */
  60         if (*temp != '/') temp = strrchr(result_string, '/');
  61         if (temp != NULL && *temp == '/') result_string = temp + 1;
  62   }
  63
  64   /* Remove the suffix, if any. */
  65   if (argc > 2) {
  66         suffix_len = strlen(argv[2]);
  67         suffix_start = strlen(result_string) - suffix_len;
  68         if (suffix_start > 0)
  69                 if (strcmp(result_string + suffix_start, argv[2]) == EOS)
  70                         *(result_string + suffix_start) = EOS;
  71   }
  72
  73   /* Print the resultant string. */
  74   printf("%s\n", result_string);
  75   return(0);
  76 }