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