diff options
Diffstat (limited to 'reference/C/CONTRIB/SNIP/posixdir.c')
| -rwxr-xr-x | reference/C/CONTRIB/SNIP/posixdir.c | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/reference/C/CONTRIB/SNIP/posixdir.c b/reference/C/CONTRIB/SNIP/posixdir.c new file mode 100755 index 0000000..81f83a2 --- /dev/null +++ b/reference/C/CONTRIB/SNIP/posixdir.c @@ -0,0 +1,276 @@ +/*
+** POSIXDIR.C - POSIX-style directory processing
+**
+** Original Copyright 1988-1991 by Bob Stout as part of
+** the MicroFirm Function Library (MFL)
+**
+** This subset version is functionally identical to the
+** version originally published by the author in Tech Specialist
+** magazine and is hereby donated to the public domain.
+*/
+
+#include <string.h>
+#include <stdlib.h>
+#include <dos.h>
+#include <io.h>
+#include <errno.h>
+#include "dirent.h"
+
+#define _NDIRS 20
+#define SUCCESS 0
+#define ERROR -1
+
+#define LAST_CHAR(s) ((char *)(s))[strlen(s) - 1]
+
+int DFerr;
+DOS_DIR _DIRS[_NDIRS]; /* Initilize DOS_DIR array to zeros */
+
+/*
+** Convert Unix-style pathnames to DOS-style
+*/
+
+static char *unix2dos(char *path)
+{
+ char *p;
+
+ while (NULL != (p = strchr(path, '/')))
+ *p = '\\';
+ return path;
+}
+
+/****************************************************************/
+/* */
+/* opendir() */
+/* */
+/* Function: Open a directory for reading. */
+/* */
+/* Parameters: 1 - Directory name. May include path spec. */
+/* */
+/* Returns: Pointer to a DOS_DIR typedef'ed structure, similar */
+/* to fopen() returning a FILE pointer. */
+/* */
+/* NULL if error, DFerr set as follows: */
+/* SUCCESS - No error */
+/* ENOENT - Could not locate directory or contents */
+/* ENOTDIR - Not a directory */
+/* ENOMEM - Too many directories already open */
+/* */
+/* Side effects: The dd_size element of the DOS_DIR structure */
+/* will contain a number representing the total */
+/* number of entries in the directory. The */
+/* dd_loc element will be set to zero since */
+/* no elements have, as yet, been read. */
+/* */
+/****************************************************************/
+
+DOS_DIR *opendir(char *fname)
+{
+ int i;
+ unsigned n = 0;
+ char nametmp[13], *p;
+ struct DSTRUCT dstruct;
+
+ for (i = 0; i < _NDIRS; ++i)
+ {
+ if (!_DIRS[i].dd_fd)
+ break;
+ }
+ if (_NDIRS <= i)
+ {
+ DFerr = ENOMEM;
+ return NULL;
+ }
+
+ unix2dos(fname);
+ if (':' == fname[1] && 1 < strlen(fname))
+ p = &fname[2];
+ else p = fname;
+ while ('\\' == LAST_CHAR(p) && 1 < strlen(p))
+ LAST_CHAR(p) = '\0';
+
+ if (strcmp(p, "\\") && strlen(p))
+ {
+ if (NULL == (rfind_1st(fname, FA_ANY, &_DIRS[i].dd_buf)))
+ {
+ DFerr = ENOENT;
+ return NULL;
+ }
+ if (!(FA_DIREC & _DIRS[i].dd_buf.ATTRIBUTE))
+ {
+ DFerr = ENOTDIR;
+ return NULL;
+ }
+ }
+ strcpy(_DIRS[i].dd_dirname, fname);
+ if (!strlen(p))
+ strcat(_DIRS[i].dd_dirname, ".");
+ if ('\\' != LAST_CHAR(_DIRS[i].dd_dirname))
+ strcat(_DIRS[i].dd_dirname, "\\");
+ strcat(strupr(_DIRS[i].dd_dirname), "*.*");
+ if (NULL == rfind_1st(_DIRS[i].dd_dirname, FA_ANY, &_DIRS[i].dd_buf))
+ {
+ DFerr = ENOENT;
+ return NULL;
+ }
+ memcpy(&dstruct, &_DIRS[i].dd_buf, sizeof(struct DSTRUCT));
+ do
+ {
+ ++n;
+ } while (rfind_nxt(&_DIRS[i].dd_buf));
+ memcpy(&_DIRS[i].dd_buf, &dstruct, sizeof(struct DSTRUCT));
+ _DIRS[i].dd_size = n;
+ _DIRS[i].dd_loc = 0;
+ _DIRS[i].dd_fd = i + 1;
+ DFerr = SUCCESS;
+ return &_DIRS[i];
+}
+
+/****************************************************************/
+/* */
+/* closedir() */
+/* */
+/* Function: Close a preeviously opened directory. */
+/* */
+/* Parameters: 1 - DOS_DIR pointer of directory to close. */
+/* */
+/* Returns: SUCCESS or ERROR. */
+/* */
+/****************************************************************/
+
+int closedir(DOS_DIR *dirp)
+{
+ if (0 == dirp->dd_fd || _NDIRS < dirp->dd_fd)
+ {
+ DFerr = EBADF;
+ return ERROR;
+ }
+ memset(dirp, 0, sizeof(DOS_DIR));
+ return SUCCESS;
+}
+
+/****************************************************************/
+/* */
+/* rewinddir() */
+/* */
+/* Function: Reset an open DOS_DIR to its first entry. */
+/* */
+/* Parameters: 1 - DOS_DIR pointer of directory to rewind. */
+/* */
+/* Returns: SUCCESS or ERROR. */
+/* */
+/****************************************************************/
+
+int rewinddir(DOS_DIR *dirp)
+{
+ if (0 == dirp->dd_fd || _NDIRS < dirp->dd_fd)
+ {
+ DFerr = EBADF;
+ return ERROR;
+ }
+ rfind_1st(dirp->dd_dirname, FA_ANY, &(dirp->dd_buf));
+ dirp->dd_loc = 0;
+ return SUCCESS;
+}
+
+/****************************************************************/
+/* */
+/* seekdir() */
+/* */
+/* Function: Point to a selected entry in a DOS_DIR. */
+/* */
+/* Parameters: 1 - DOS_DIR pointer of directory to rewind. */
+/* 2 - Offset of entry to seek */
+/* 3 - Origin of offset */
+/* */
+/* Returns: A DSTRUCT pointer, same as returned by rfind_1st() */
+/* and rfind_nxt(). */
+/* */
+/* NULL if error, DFerr set as follows: */
+/* SUCCESS - No error */
+/* EBADF - Bad file (DOS_DIR) pointer */
+/* EACCES - Illegal origin specification */
+/* EOF - Attempt to seek past end of directory */
+/* */
+/****************************************************************/
+
+struct DSTRUCT *seekdir(DOS_DIR *dirp, int offset, int origin)
+{
+ int i, loc;
+
+ if (0 == dirp->dd_fd || _NDIRS < dirp->dd_fd)
+ {
+ DFerr = EBADF;
+ return NULL;
+ }
+ switch (origin)
+ {
+ case SEEK_SET:
+ loc = offset + 1;
+ break;
+ case SEEK_CUR:
+ loc = dirp->dd_loc + offset;
+ break;
+ case SEEK_END:
+ loc = dirp->dd_size + offset;
+ break;
+ default:
+ DFerr = EACCES;
+ return NULL;
+ }
+
+ if (loc > (int)dirp->dd_size || 0 >= loc)
+ {
+ DFerr = EOF;
+ return NULL;
+ }
+
+ rewinddir(dirp);
+ for (i = 0; i < loc; ++i)
+ readdir(dirp);
+
+ DFerr = SUCCESS;
+ return (&(dirp->dd_buf));
+}
+
+/****************************************************************/
+/* */
+/* readdir() */
+/* */
+/* Function: Reads entries from an open directory. */
+/* */
+/* Parameters: 1 - DOS_DIR pointer of directory to read. */
+/* */
+/* Returns: A DSTRUCT pointer, same as returned by rfind_1st() */
+/* and rfind_nxt(). */
+/* */
+/* NULL if error, DFerr set as follows: */
+/* SUCCESS - No error */
+/* EBADF - Bad file (DOS_DIR) pointer */
+/* EOF - Attempt to read past end of directory */
+/* */
+/* Side effects: The dd_loc element of the DOS_DIR structure */
+/* will contain a number representing which */
+/* element of the directory was returned. It may */
+/* range from 1 to dd_size. */
+/* */
+/****************************************************************/
+
+struct DSTRUCT *readdir(DOS_DIR *dirp)
+{
+ if (0 == dirp->dd_fd || _NDIRS < dirp->dd_fd)
+ {
+ DFerr = EBADF;
+ return NULL;
+ }
+ if (0 == dirp->dd_loc || NULL != rfind_nxt(&(dirp->dd_buf)))
+ {
+ dirp->dd_loc += 1;
+ DFerr = SUCCESS;
+ return (&(dirp->dd_buf));
+ }
+ else
+ {
+ DFerr = EOF;
+ return NULL;
+ }
+}
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