1 files changed, 67 insertions, 0 deletions
diff --git a/cat.c b/cat.c
new file mode 100644
index 0000000..30f2f3d
--- /dev/null
+++ b/cat.c
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/*
+ * Copyright (C) 2022, 2023 Ferass El Hafidi <vitali64pmemail@protonmail.com>
+ * Copyright (C) 2022 Leah Rowe <leah@libreboot.org>
+ */
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#define REQ_PRINT_USAGE /* Require print_usage() from common.h */
+#define REQ_ERRPRINT /* Require errprint() from common.h */
+#define DESCRIPTION "Concatenate a file to standard output. \
+	If no file is specified or file is '-', read standard input."
+#define OPERANDS    "[-u] [file] ..."
+#include "common.h"
+
+int cat(int flides, int unbuffered);
+
+#ifdef FASESBOX
+int cat_main(int argc, char *argv[]) {
+#else
+int main(int argc, char *argv[]) {
+#endif
+	int file, argument, i = 1, unbuffered, err;
+	char *argv0 = strdup(argv[0]);
+	while ((argument = getopt(argc, argv, "u")) != -1) {
+		if (argument == '?') {
+			print_usage(argv[0], DESCRIPTION, OPERANDS, VERSION);
+			return 1;
+		}
+		else if (argument == 'u')
+			unbuffered = 1;
+	} argc -= optind; argv += optind;
+
+	
+	if (argc < 1) {
+		return errprint(argv0, "-", cat(STDIN_FILENO, unbuffered));
+	}
+
+	for (i = 0; i != argc; i++) {
+		if (strcmp(argv[i], "-")) file = open(argv[i], O_RDONLY);
+		else file = STDIN_FILENO;
+		if (file == -1)
+			return errprint(argv0, argv[i], errno); /* Something went wrong */
+		err = errprint(argv0, argv[i], cat(file, unbuffered));
+		close(file);
+	}
+	return err;
+}
+
+int cat(int fildes, int unbuffered) {
+	char s[4096];
+	FILE *filstr;
+	size_t length;
+	if (unbuffered) while ((length = read(fildes, s, 4096)) > 0)
+		write(STDOUT_FILENO, s, length);
+	else {
+		if (fildes != STDIN_FILENO) filstr = fdopen(fildes, "r");
+		else filstr = stdin;
+		while ((length = fread(s, 4096, 1, filstr)) > 0)
+			fwrite(s, length, 1, stdout);
+	}
+	if (errno) return errno;
+	return 0;
+}