usr/src/lib/libcmd/common/basename.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1992-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                                                                      *
  20 ***********************************************************************/
  21 #pragma prototyped
  22 /*
  23  * David Korn
  24  * AT&T Bell Laboratories
  25  *
  26  * namebase pathname [suffix]
  27  *
  28  * print the namebase of a pathname
  29  */
  30
  31 static const char usage[] =
  32 "[-?\n@(#)$Id: basename (AT&T Research) 1999-04-10 $\n]"
  33 USAGE_LICENSE
  34 "[+NAME?basename - strip directory and suffix from filenames]"
  35 "[+DESCRIPTION?\bbasename\b removes all leading directory components "
  36         "from the file name defined by \astring\a.  If the file name "
  37         "defined by \astring\a has a suffix that ends in \asuffix\a, "
  38         "it is removed as well.]"
  39 "[+?If \astring\a consists solely of \b/\b characters the output will "
  40         "be a single \b/\b unless \bPATH_LEADING_SLASHES\b returned by "
  41         "\bgetconf\b(1) is \b1\b and \astring\a consists of multiple "
  42         "\b/\b characters in which case \b//\b will be output.  "
  43         "Otherwise, trailing \b/\b characters are removed, and if "
  44         "there are any remaining \b/\b characters in \astring\a, "
  45         "all characters up to and including the last \b/\b are removed.  "
  46         "Finally, if \asuffix\a is specified, and is identical the end "
  47         "of \astring\a, these characters are removed.  The characters "
  48         "not removed from \astring\a will be written to standard output.]"
  49 "\n"
  50 "\n string [suffix]\n"
  51 "\n"
  52 "[+EXIT STATUS?]{"
  53         "[+0?Successful Completion.]"
  54         "[+>0?An error occurred.]"
  55 "}"
  56 "[+SEE ALSO?\bdirname\b(1), \bgetconf\b(1), \bbasename\b(3)]"
  57 ;
  58
  59
  60 #include <cmd.h>
  61
  62 static void namebase(Sfio_t *outfile, register char *pathname, char *suffix)
  63 {
  64         register char *first, *last;
  65         register int n=0;
  66         for(first=last=pathname; *last; last++);
  67         /* back over trailing '/' */
  68         if(last>first)
  69                 while(*--last=='/' && last > first);
  70         if(last==first && *last=='/')
  71         {
  72                 /* all '/' or "" */
  73                 if(*first=='/')
  74                         if(*++last=='/')        /* keep leading // */
  75                                 last++;
  76         }
  77         else
  78         {
  79                 for(first=last++;first>pathname && *first!='/';first--);
  80                 if(*first=='/')
  81                         first++;
  82                 /* check for trailing suffix */
  83                 if(suffix && (n=strlen(suffix)) && n<(last-first))
  84                 {
  85                         if(memcmp(last-n,suffix,n)==0)
  86                                 last -=n;
  87                 }
  88         }
  89         if(last>first)
  90                 sfwrite(outfile,first,last-first);
  91         sfputc(outfile,'\n');
  92 }
  93
  94 int
  95 b_basename(int argc,register char *argv[], void* context)
  96 {
  97         register int  n;
  98
  99         cmdinit(argc, argv, context, ERROR_CATALOG, 0);
 100         while (n = optget(argv, usage)) switch (n)
 101         {
 102         case ':':
 103                 error(2, "%s", opt_info.arg);
 104                 break;
 105         case '?':
 106                 error(ERROR_usage(2), "%s", opt_info.arg);
 107                 break;
 108         }
 109         argv += opt_info.index;
 110         argc -= opt_info.index;
 111         if(error_info.errors || argc < 1 || argc > 2)
 112                 error(ERROR_usage(2), "%s", optusage(NiL));
 113         namebase(sfstdout,argv[0],argv[1]);
 114         return(0);
 115 }
 116