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         char            d_buf[21];
  48         char            d_attribute;
  49         unsigned short  d_time;
  50         unsigned short  d_date;
  51         long            d_size;
  52         char            d_name[13];
  53 } Dta_buf;
  54
  55 static  char    *getdirent();
  56 static  void    mysetdta();
  57 static  void    free_dircontents();
  58
  59 static  Dta_buf         dtabuf;
  60 static  Dta_buf         *dtapnt = &dtabuf;
  61 static  union REGS      reg, nreg;
  62
  63 #if     defined(M_I86LM)
  64 static  struct SREGS    sreg;
  65 #endif
  66
  67 DIR     *
  68 opendir(name)
  69         char    *name;
  70 {
  71         struct  stat            statb;
  72         DIR                     *dirp;
  73         char                    c;
  74         char                    *s;
  75         struct _dircontents     *dp;
  76         char                    nbuf[MAXPATHLEN + 1];
  77
  78         if (stat(name, &statb) < 0 || (statb.st_mode & S_IFMT) != S_IFDIR)
  79                 return (DIR *) NULL;
  80         if (Newisnull(dirp, DIR))
  81                 return (DIR *) NULL;
  82         if (*name && (c = name[strlen(name) - 1]) != '\\' && c != '/')
  83                 (void) strcat(strcpy(nbuf, name), "\\*.*");
  84         else
  85                 (void) strcat(strcpy(nbuf, name), "*.*");
  86         dirp->dd_loc = 0;
  87         mysetdta();
  88         dirp->dd_contents = dirp->dd_cp = (struct _dircontents *) NULL;
  89         if ((s = getdirent(nbuf)) == (char *) NULL)
  90                 return dirp;
  91         do {
  92                 if (Newisnull(dp, struct _dircontents) || (dp->_d_entry =
  93                         malloc((unsigned) (strlen(s) + 1))) == (char *) NULL)
  94                 {
  95                         if (dp)
  96                                 free((char *) dp);
  97                         free_dircontents(dirp->dd_contents);
  98                         return (DIR *) NULL;
  99                 }
 100                 if (dirp->dd_contents)
 101                         dirp->dd_cp = dirp->dd_cp->_d_next = dp;
 102                 else
 103                         dirp->dd_contents = dirp->dd_cp = dp;
 104                 (void) strcpy(dp->_d_entry, s);
 105                 dp->_d_next = (struct _dircontents *) NULL;
 106         } while ((s = getdirent((char *) NULL)) != (char *) NULL);
 107         dirp->dd_cp = dirp->dd_contents;
 108
 109         return dirp;
 110 }
 111
 112 void
 113 closedir(dirp)
 114         DIR     *dirp;
 115 {
 116         free_dircontents(dirp->dd_contents);
 117         free((char *) dirp);
 118 }
 119
 120 struct dirent   *
 121 readdir(dirp)
 122         DIR     *dirp;
 123 {
 124         static  struct dirent   dp;
 125
 126         if (dirp->dd_cp == (struct _dircontents *) NULL)
 127                 return (struct dirent *) NULL;
 128         dp.d_namlen = dp.d_reclen =
 129                 strlen(strcpy(dp.d_name, dirp->dd_cp->_d_entry));
 130         strlwr(dp.d_name);              /* JF */
 131         dp.d_ino = 0;
 132         dirp->dd_cp = dirp->dd_cp->_d_next;
 133         dirp->dd_loc++;
 134
 135         return &dp;
 136 }
 137
 138 void
 139 seekdir(dirp, off)
 140         DIR     *dirp;
 141         long    off;
 142 {
 143         long                    i = off;
 144         struct _dircontents     *dp;
 145
 146         if (off < 0)
 147                 return;
 148         for (dp = dirp->dd_contents ; --i >= 0 && dp ; dp = dp->_d_next)
 149                 ;
 150         dirp->dd_loc = off - (i + 1);
 151         dirp->dd_cp = dp;
 152 }
 153
 154 long
 155 telldir(dirp)
 156         DIR     *dirp;
 157 {
 158         return dirp->dd_loc;
 159 }
 160
 161 static  void
 162 free_dircontents(dp)
 163         struct  _dircontents    *dp;
 164 {
 165         struct _dircontents     *odp;
 166
 167         while (dp) {
 168                 if (dp->_d_entry)
 169                         free(dp->_d_entry);
 170                 dp = (odp = dp)->_d_next;
 171                 free((char *) odp);
 172         }
 173 }
 174
 175 static  char    *
 176 getdirent(dir)
 177         char    *dir;
 178 {
 179         if (dir != (char *) NULL) {             /* get first entry */
 180                 reg.h.ah = DOSI_FINDF;
 181                 reg.h.cl = ATTRIBUTES;
 182 #if     defined(M_I86LM)
 183                 reg.x.dx = FP_OFF(dir);
 184                 sreg.ds = FP_SEG(dir);
 185 #else
 186                 reg.x.dx = (unsigned) dir;
 187 #endif
 188         } else {                                /* get next entry */
 189                 reg.h.ah = DOSI_FINDN;
 190 #if     defined(M_I86LM)
 191                 reg.x.dx = FP_OFF(dtapnt);
 192                 sreg.ds = FP_SEG(dtapnt);
 193 #else
 194                 reg.x.dx = (unsigned) dtapnt;
 195 #endif
 196         }
 197 #if     defined(M_I86LM)
 198         intdosx(&reg, &nreg, &sreg);
 199 #else
 200         intdos(&reg, &nreg);
 201 #endif
 202         if (nreg.x.cflag)
 203                 return (char *) NULL;
 204
 205         return dtabuf.d_name;
 206 }
 207
 208 static  void
 209 mysetdta()
 210 {
 211         reg.h.ah = DOSI_SDTA;
 212 #if     defined(M_I86LM)
 213         reg.x.dx = FP_OFF(dtapnt);
 214         sreg.ds = FP_SEG(dtapnt);
 215         intdosx(&reg, &nreg, &sreg);
 216 #else
 217         reg.x.dx = (int) dtapnt;
 218         intdos(&reg, &nreg);
 219 #endif
 220 }