1 files changed, 78 insertions, 0 deletions
diff --git a/src/cmd/ls/ls.c b/src/cmd/ls/ls.c
new file mode 100755
index 0000000..a937457
--- /dev/null
+++ b/src/cmd/ls/ls.c
@@ -0,0 +1,78 @@
+/* TODO:
+ * - add flags
+ * - add option to print more file information
+ */
+#include <stdio.h>
+#include <sys/types.h>
+#include <dirent.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/stat.h>
+
+void dirwalk(DIR *);
+void error(char *);
+void printdirent(struct dirent *);
+void printfile(char *);
+
+/* print information about files and directories */
+int main(int argc, char **argv)
+{
+	DIR *dp;
+	if (argc == 1) {
+		if ((dp = opendir(".")) == NULL) {
+			perror("ls");
+			return -1;
+		}
+		dirwalk(dp);
+	} else if (argc == 2) {
+		if ((dp = opendir(argv[1])) == NULL) {
+			perror("ls");
+			return -1;
+		}
+		dirwalk(dp);
+	} else {
+		while (--argc > 0 && !ferror(stdout)) {
+			errno = 0;
+			if ((dp = opendir(*++argv)) == NULL) {
+				perror("ls");
+				continue;
+			}
+			dirwalk(dp);
+		}
+	}
+}
+
+/* dirwalk: read all the directory entries in a directory */
+void dirwalk(DIR *d)
+{
+	struct dirent *dir;
+	while ((dir = readdir(d)) != NULL) {
+		errno = 0;
+		if (strcmp(dir->d_name, ".") == 0 || strcmp(dir->d_name, "..") == 0)
+			continue;
+		printdirent(dir);
+	}
+	if (errno != 0) {
+		perror("ls");
+	}
+}
+
+/* printdirent: print a directory entry and any selected information */
+void printdirent(struct dirent *dir)
+{
+	printf("%s\n", dir->d_name);
+}
+
+/* printfile: print a file and any other selected information */
+void printfile(char *name)
+{
+	struct stat stbuf;
+	int e = stat(name, &stbuf);
+	if (e != 0) {
+		perror("ls");
+		return;
+	}
+	printf("%s\n", name);
+}
+