external/ibm-public/postfix/dist/src/util/sane_basename.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      sane_basename 3
   6 /* SUMMARY
   7 /*      split pathname into last component and parent directory
   8 /* SYNOPSIS
   9 /*      #include <stringops.h>
  10 /*
  11 /*      char    *sane_basename(buf, path)
  12 /*      VSTRING *buf;
  13 /*      const char *path;
  14 /*
  15 /*      char    *sane_dirname(buf, path)
  16 /*      VSTRING *buf;
  17 /*      const char *path;
  18 /* DESCRIPTION
  19 /*      These functions split a pathname into its last component
  20 /*      and its parent directory, excluding any trailing "/"
  21 /*      characters from the input. The result is a pointer to "/"
  22 /*      when the input is all "/" characters, or a pointer to "."
  23 /*      when the input is a null pointer or zero-length string.
  24 /*
  25 /*      sane_basename() and sane_dirname() differ as follows
  26 /*      from standard basename() and dirname() implementations:
  27 /* .IP \(bu
  28 /*      They can use caller-provided storage or private storage.
  29 /* .IP \(bu
  30 /*      They never modify their input.
  31 /* .PP
  32 /*      sane_basename() returns a pointer to string with the last
  33 /*      pathname component.
  34 /*
  35 /*      sane_dirname() returns a pointer to string with the parent
  36 /*      directory. The result is a pointer to "." when the input
  37 /*      contains no '/' character.
  38 /*
  39 /*      Arguments:
  40 /* .IP buf
  41 /*      Result storage. If a null pointer is specified, each function
  42 /*      uses its own private memory that is overwritten upon each call.
  43 /* .IP path
  44 /*      The input pathname.
  45 /* LICENSE
  46 /* .ad
  47 /* .fi
  48 /*      The Secure Mailer license must be distributed with this
  49 /*      software.
  50 /* AUTHOR(S)
  51 /*      Wietse Venema
  52 /*      IBM T.J. Watson Research
  53 /*      P.O. Box 704
  54 /*      Yorktown Heights, NY 10598, USA
  55 /*--*/
  56
  57 /* System library. */
  58
  59 #include <sys_defs.h>
  60 #include <string.h>
  61
  62 /* Utility library. */
  63
  64 #include <vstring.h>
  65 #include <stringops.h>
  66
  67 #define STR(x)  vstring_str(x)
  68
  69 /* sane_basename - skip directory prefix */
  70
  71 char   *sane_basename(VSTRING *bp, const char *path)
  72 {
  73     static VSTRING *buf;
  74     const char *first;
  75     const char *last;
  76
  77     /*
  78      * Your buffer or mine?
  79      */
  80     if (bp == 0) {
  81         bp = buf;
  82         if (bp == 0)
  83             bp = buf = vstring_alloc(10);
  84     }
  85
  86     /*
  87      * Special case: return "." for null or zero-length input.
  88      */
  89     if (path == 0 || *path == 0)
  90         return (STR(vstring_strcpy(bp, ".")));
  91
  92     /*
  93      * Remove trailing '/' characters from input. Return "/" if input is all
  94      * '/' characters.
  95      */
  96     last = path + strlen(path) - 1;
  97     while (*last == '/') {
  98         if (last == path)
  99             return (STR(vstring_strcpy(bp, "/")));
 100         last--;
 101     }
 102
 103     /*
 104      * The pathname does not end in '/'. Skip to last '/' character if any.
 105      */
 106     first = last - 1;
 107     while (first >= path && *first != '/')
 108         first--;
 109
 110     return (STR(vstring_strncpy(bp, first + 1, last - first)));
 111 }
 112
 113 /* sane_dirname - keep directory prefix */
 114
 115 char   *sane_dirname(VSTRING *bp, const char *path)
 116 {
 117     static VSTRING *buf;
 118     const char *last;
 119
 120     /*
 121      * Your buffer or mine?
 122      */
 123     if (bp == 0) {
 124         bp = buf;
 125         if (bp == 0)
 126             bp = buf = vstring_alloc(10);
 127     }
 128
 129     /*
 130      * Special case: return "." for null or zero-length input.
 131      */
 132     if (path == 0 || *path == 0)
 133         return (STR(vstring_strcpy(bp, ".")));
 134
 135     /*
 136      * Remove trailing '/' characters from input. Return "/" if input is all
 137      * '/' characters.
 138      */
 139     last = path + strlen(path) - 1;
 140     while (*last == '/') {
 141         if (last == path)
 142             return (STR(vstring_strcpy(bp, "/")));
 143         last--;
 144     }
 145
 146     /*
 147      * This pathname does not end in '/'. Skip to last '/' character if any.
 148      */
 149     while (last >= path && *last != '/')
 150         last--;
 151     if (last < path)                            /* no '/' */
 152         return (STR(vstring_strcpy(bp, ".")));
 153
 154     /*
 155      * Strip trailing '/' characters from dirname (not strictly needed).
 156      */
 157     while (last > path && *last == '/')
 158         last--;
 159
 160     return (STR(vstring_strncpy(bp, path, last - path + 1)));
 161 }
 162
 163 #ifdef TEST
 164 #include <vstring_vstream.h>
 165
 166 int     main(int argc, char **argv)
 167 {
 168     VSTRING *buf = vstring_alloc(10);
 169     char   *dir;
 170     char   *base;
 171
 172     while (vstring_get_nonl(buf, VSTREAM_IN) > 0) {
 173         dir = sane_dirname((VSTRING *) 0, STR(buf));
 174         base = sane_basename((VSTRING *) 0, STR(buf));
 175         vstream_printf("input=\"%s\" dir=\"%s\" base=\"%s\"\n",
 176                        STR(buf), dir, base);
 177     }
 178     vstream_fflush(VSTREAM_OUT);
 179     vstring_free(buf);
 180     return (0);
 181 }
 182
 183 #endif