add directory study

study/linux-travel/MINIX-1.5/1.5/Source/commands/traverse.c

@@ -0,0 +1,91 @@
+/* traverse - traverse a tree		Author:	Gary Perlman */
+
+#include <sys/types.h>
+#include <sys/dir.h>
+#include <stdio.h>
+
+#define STANDALONE
+
+#define	DIR	FILE
+#define	MAXNAME (DIRSIZ+2)
+#define	opendir(path) fopen (path, "r")
+#define closedir(dirp) fclose (dirp)
+
+struct direct *readdir(dirp)
+DIR *dirp;
+{
+  static struct direct entry;
+  if (dirp == NULL) return((struct direct *) NULL);
+  for (;;) {
+	if (fread(&entry, sizeof(struct direct), 1, dirp) == 0)
+		return((struct direct *) NULL);
+	if (entry.d_ino) return(&entry);
+  }
+}
+
+char *strncpy();
+
+char *namedir(entry)
+struct direct *entry;
+{
+  static char name[MAXNAME];
+  return(strncpy(name, entry->d_name, DIRSIZ));
+}
+
+
+#include <sys/stat.h>
+#define	isdir(path) (stat(path, &buf) ? 0 : (buf.st_mode&S_IFMT)==S_IFDIR)
+
+traverse(path, func)
+char *path;
+int (*func) ();
+{
+  DIR *dirp;
+  struct direct *entry;
+  struct stat buf;
+  int filetype = isdir(path) ? 'd' : 'f';
+  (*func) (path, filetype, 0);
+  if (filetype == 'd') {
+	if (chdir(path) == 0) {
+		if (dirp = opendir(".")) {
+			while (entry = readdir(dirp)) {
+				char name[MAXNAME];
+				(void) strcpy(name, namedir(entry));
+				if (strcmp(name, ".") && strcmp(name, ".."))
+					traverse(name, func);
+			}
+			(void) closedir(dirp);
+		}
+		(void) chdir("..");
+	}
+  }
+  (*func) (path, filetype, 1);
+}
+
+#ifdef STANDALONE
+
+static Indent = 0;
+tryverse(file, type, pos)
+char *file;
+{
+  int in;
+  if (pos == 0) {
+	for (in = 0; in < Indent; in++) putchar('\t');
+	if (type == 'd') {
+		printf("%s/\n", file);
+		Indent++;
+	} else
+		puts(file);
+  } else if (type == 'd')
+	Indent--;
+}
+
+main(argc, argv)
+char **argv;
+{
+  int tryverse();
+  char *root = argc > 1 ? argv[1] : ".";
+  traverse(root, tryverse);
+}
+
+#endif