Dogcows Code - chaz/tar/blob - src/msd_dir.c

   1 /*
   2  * @(#)msd_dir.c 1.4 87/11/06   Public Domain.
   3  *
   4  *  A public domain implementation of BSD directory routines for
   5  *  MS-DOS.  Written by Michael Rendell ({uunet,utai}michael@garfield),
   6  *  August 1897
   7  */
   8
   9 #include        <sys/types.h>
  10 #include        <sys/stat.h>
  11 #include        "msd_dir.h"
  12 #ifndef __TURBOC__
  13 #include        <malloc.h>
  14 #else
  15 #include        <stdlib.h>
  16 #endif
  17 #include        <string.h>
  18 #include        <dos.h>
  19
  20 #ifndef NULL
  21 # define        NULL    0
  22 #endif /* NULL */
  23
  24 #ifndef MAXPATHLEN
  25 # define        MAXPATHLEN      255
  26 #endif /* MAXPATHLEN */
  27
  28 /* attribute stuff */
  29 #define A_RONLY         0x01
  30 #define A_HIDDEN        0x02
  31 #define A_SYSTEM        0x04
  32 #define A_LABEL         0x08
  33 #define A_DIR           0x10
  34 #define A_ARCHIVE       0x20
  35
  36 /* dos call values */
  37 #define DOSI_FINDF      0x4e
  38 #define DOSI_FINDN      0x4f
  39 #define DOSI_SDTA       0x1a
  40
  41 #define Newisnull(a, t)         ((a = (t *) malloc(sizeof(t))) == (t *) NULL)
  42 /* #define      ATTRIBUTES              (A_DIR | A_HIDDEN | A_SYSTEM) */
  43 #define ATTRIBUTES      (A_RONLY | A_SYSTEM | A_DIR)
  44
  45 /* what find first/next calls look use */
  46 typedef struct
  47   {
  48     char d_buf[21];
  49     char d_attribute;
  50     unsigned short d_time;
  51     unsigned short d_date;
  52     long d_size;
  53     char d_name[13];
  54   }
  55
  56 Dta_buf;
  57
  58 static char *getdirent ();
  59 static void mysetdta ();
  60 static void free_dircontents ();
  61
  62 static Dta_buf dtabuf;
  63 static Dta_buf *dtapnt = &dtabuf;
  64 static union REGS reg, nreg;
  65
  66 #if     defined(M_I86LM)
  67 static struct SREGS sreg;
  68 #endif
  69
  70 DIR *
  71 opendir (name)
  72      char *name;
  73 {
  74   struct stat statb;
  75   DIR *dirp;
  76   char c;
  77   char *s;
  78   struct _dircontents *dp;
  79   char nbuf[MAXPATHLEN + 1];
  80
  81   if (stat (name, &statb) < 0 || (statb.st_mode & S_IFMT) != S_IFDIR)
  82     return (DIR *) NULL;
  83   if (Newisnull (dirp, DIR))
  84     return (DIR *) NULL;
  85   if (*name && (c = name[strlen (name) - 1]) != '\\' && c != '/')
  86     (void) strcat (strcpy (nbuf, name), "\\*.*");
  87   else
  88     (void) strcat (strcpy (nbuf, name), "*.*");
  89   dirp->dd_loc = 0;
  90   mysetdta ();
  91   dirp->dd_contents = dirp->dd_cp = (struct _dircontents *) NULL;
  92   if ((s = getdirent (nbuf)) == (char *) NULL)
  93     return dirp;
  94   do
  95     {
  96       if (Newisnull (dp, struct _dircontents) || (dp->_d_entry =
  97                      malloc ((unsigned) (strlen (s) + 1))) == (char *) NULL)
  98         {
  99           if (dp)
 100             free ((char *) dp);
 101           free_dircontents (dirp->dd_contents);
 102           return (DIR *) NULL;
 103         }
 104       if (dirp->dd_contents)
 105         dirp->dd_cp = dirp->dd_cp->_d_next = dp;
 106       else
 107         dirp->dd_contents = dirp->dd_cp = dp;
 108       (void) strcpy (dp->_d_entry, s);
 109       dp->_d_next = (struct _dircontents *) NULL;
 110     }
 111   while ((s = getdirent ((char *) NULL)) != (char *) NULL);
 112   dirp->dd_cp = dirp->dd_contents;
 113
 114   return dirp;
 115 }
 116
 117 void
 118 closedir (dirp)
 119      DIR *dirp;
 120 {
 121   free_dircontents (dirp->dd_contents);
 122   free ((char *) dirp);
 123 }
 124
 125 struct dirent *
 126 readdir (dirp)
 127      DIR *dirp;
 128 {
 129   static struct dirent dp;
 130
 131   if (dirp->dd_cp == (struct _dircontents *) NULL)
 132     return (struct dirent *) NULL;
 133   dp.d_namlen = dp.d_reclen =
 134     strlen (strcpy (dp.d_name, dirp->dd_cp->_d_entry));
 135   strlwr (dp.d_name);           /* JF */
 136   dp.d_ino = 0;
 137   dirp->dd_cp = dirp->dd_cp->_d_next;
 138   dirp->dd_loc++;
 139
 140   return &dp;
 141 }
 142
 143 void
 144 seekdir (dirp, off)
 145      DIR *dirp;
 146      long off;
 147 {
 148   long i = off;
 149   struct _dircontents *dp;
 150
 151   if (off < 0)
 152     return;
 153   for (dp = dirp->dd_contents; --i >= 0 && dp; dp = dp->_d_next)
 154     ;
 155   dirp->dd_loc = off - (i + 1);
 156   dirp->dd_cp = dp;
 157 }
 158
 159 long
 160 telldir (dirp)
 161      DIR *dirp;
 162 {
 163   return dirp->dd_loc;
 164 }
 165
 166 static void
 167 free_dircontents (dp)
 168      struct _dircontents *dp;
 169 {
 170   struct _dircontents *odp;
 171
 172   while (dp)
 173     {
 174       if (dp->_d_entry)
 175         free (dp->_d_entry);
 176       dp = (odp = dp)->_d_next;
 177       free ((char *) odp);
 178     }
 179 }
 180
 181 static char *
 182 getdirent (dir)
 183      char *dir;
 184 {
 185   if (dir != (char *) NULL)
 186     {                           /* get first entry */
 187       reg.h.ah = DOSI_FINDF;
 188       reg.h.cl = ATTRIBUTES;
 189 #if     defined(M_I86LM)
 190       reg.x.dx = FP_OFF (dir);
 191       sreg.ds = FP_SEG (dir);
 192 #else
 193       reg.x.dx = (unsigned) dir;
 194 #endif
 195     }
 196   else
 197     {                           /* get next entry */
 198       reg.h.ah = DOSI_FINDN;
 199 #if     defined(M_I86LM)
 200       reg.x.dx = FP_OFF (dtapnt);
 201       sreg.ds = FP_SEG (dtapnt);
 202 #else
 203       reg.x.dx = (unsigned) dtapnt;
 204 #endif
 205     }
 206 #if     defined(M_I86LM)
 207   intdosx (&reg, &nreg, &sreg);
 208 #else
 209   intdos (&reg, &nreg);
 210 #endif
 211   if (nreg.x.cflag)
 212     return (char *) NULL;
 213
 214   return dtabuf.d_name;
 215 }
 216
 217 static void
 218 mysetdta ()
 219 {
 220   reg.h.ah = DOSI_SDTA;
 221 #if     defined(M_I86LM)
 222   reg.x.dx = FP_OFF (dtapnt);
 223   sreg.ds = FP_SEG (dtapnt);
 224   intdosx (&reg, &nreg, &sreg);
 225 #else
 226   reg.x.dx = (int) dtapnt;
 227   intdos (&reg, &nreg);
 228 #endif
 229 }