*
* Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
*
- * Licensed under GPLv2, see file License in this tarball for details.
+ * Licensed under GPLv2, see file LICENSE in this source tree.
*/
+//config:config CAT
+//config: bool "cat (5.6 kb)"
+//config: default y
+//config: help
+//config: cat is used to concatenate files and print them to the standard
+//config: output. Enable this option if you wish to enable the 'cat' utility.
+//config:
+//config:config FEATURE_CATN
+//config: bool "Enable -n and -b options"
+//config: default y
+//config: depends on CAT
+//config: help
+//config: -n numbers all output lines while -b numbers nonempty output lines.
+//config:
+//config:config FEATURE_CATV
+//config: bool "cat -v[etA]"
+//config: default y
+//config: depends on CAT
+//config: help
+//config: Display nonprinting characters as escape sequences
+
+//applet:IF_CAT(APPLET(cat, BB_DIR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_CAT) += cat.o
/* BB_AUDIT SUSv3 compliant */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/cat.html */
-#include "libbb.h"
-
-/* This is a NOFORK applet. Be very careful! */
+//usage:#if ENABLE_FEATURE_CATN || ENABLE_FEATURE_CATV
+//usage:#define cat_trivial_usage
+//usage: "[-" IF_FEATURE_CATN("nb") IF_FEATURE_CATV("vteA") "] [FILE]..."
+//usage:#else
+//usage:#define cat_trivial_usage
+//usage: "[FILE]..."
+//usage:#endif
+//usage:#define cat_full_usage "\n\n"
+//usage: "Print FILEs to stdout\n"
+//usage: IF_FEATURE_CATN(
+//usage: "\n -n Number output lines"
+//usage: "\n -b Number nonempty lines"
+//usage: )
+//usage: IF_FEATURE_CATV(
+//usage: "\n -v Show nonprinting characters as ^x or M-x"
+//usage: "\n -t ...and tabs as ^I"
+//usage: "\n -e ...and end lines with $"
+//usage: "\n -A Same as -vte"
+//usage: )
+/*
+ Longopts not implemented yet:
+ --number-nonblank number nonempty output lines, overrides -n
+ --number number all output lines
+ --show-nonprinting use ^ and M- notation, except for LFD and TAB
+ --show-all equivalent to -vet
+ Not implemented yet:
+ -E, --show-ends display $ at end of each line (-e sans -v)
+ -T, --show-tabs display TAB characters as ^I (-t sans -v)
+ -s, --squeeze-blank suppress repeated empty output lines
+*/
+//usage:
+//usage:#define cat_example_usage
+//usage: "$ cat /proc/uptime\n"
+//usage: "110716.72 17.67"
+#include "libbb.h"
+#include "common_bufsiz.h"
-int bb_cat(char **argv)
+#if ENABLE_FEATURE_CATV
+/*
+ * cat -v implementation for busybox
+ *
+ * Copyright (C) 2006 Rob Landley <rob@landley.net>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+/* Rob had "cat -v" implemented as a separate applet, catv.
+ * See "cat -v considered harmful" at
+ * http://cm.bell-labs.com/cm/cs/doc/84/kp.ps.gz
+ * From USENIX Summer Conference Proceedings, 1983
+ * """
+ * The talk reviews reasons for UNIX's popularity and shows, using UCB cat
+ * as a primary example, how UNIX has grown fat. cat isn't for printing
+ * files with line numbers, it isn't for compressing multiple blank lines,
+ * it's not for looking at non-printing ASCII characters, it's for
+ * concatenating files.
+ * We are reminded that ls isn't the place for code to break a single column
+ * into multiple ones, and that mailnews shouldn't have its own more
+ * processing or joke encryption code.
+ * """
+ *
+ * I agree with the argument. Unfortunately, this ship has sailed (1983...).
+ * There are dozens of Linux distros and each of them has "cat" which supports -v.
+ * It's unrealistic for us to "reeducate" them to use our, incompatible way
+ * to achieve "cat -v" effect. The actual effect would be "users pissed off
+ * by gratuitous incompatibility".
+ */
+#define CAT_OPT_e (1<<0)
+#define CAT_OPT_t (1<<1)
+#define CAT_OPT_v (1<<2)
+/* -A occupies bit (1<<3) */
+#define CAT_OPT_n ((1<<4) * ENABLE_FEATURE_CATN)
+#define CAT_OPT_b ((1<<5) * ENABLE_FEATURE_CATN)
+static int catv(unsigned opts, char **argv)
{
- static const char *const argv_dash[] = { "-", NULL };
-
- int fd;
int retval = EXIT_SUCCESS;
+ int fd;
+#if ENABLE_FEATURE_CATN
+ bool eol_seen = (opts & (CAT_OPT_n|CAT_OPT_b));
+ unsigned eol_char = (eol_seen ? '\n' : 0x100);
+ unsigned skip_num_on = (opts & CAT_OPT_b) ? '\n' : 0x100;
+ unsigned lineno = 0;
+#endif
- if (!*argv)
- argv = (char**) &argv_dash;
+ BUILD_BUG_ON(CAT_OPT_e != VISIBLE_ENDLINE);
+ BUILD_BUG_ON(CAT_OPT_t != VISIBLE_SHOW_TABS);
+#if 0 /* These consts match, we can just pass "opts" to visible() */
+ if (opts & CAT_OPT_e)
+ flags |= VISIBLE_ENDLINE;
+ if (opts & CAT_OPT_t)
+ flags |= VISIBLE_SHOW_TABS;
+#endif
+#define read_buf bb_common_bufsiz1
+ setup_common_bufsiz();
do {
- fd = STDIN_FILENO;
- if (!LONE_DASH(*argv))
- fd = open_or_warn(*argv, O_RDONLY);
- if (fd >= 0) {
- /* This is not an xfunc - never exits */
- off_t r = bb_copyfd_eof(fd, STDOUT_FILENO);
- if (fd != STDIN_FILENO)
- close(fd);
- if (r >= 0)
- continue;
+ fd = open_or_warn_stdin(*argv);
+ if (fd < 0) {
+ retval = EXIT_FAILURE;
+ continue;
}
- retval = EXIT_FAILURE;
+ for (;;) {
+ int i, res;
+
+ res = read(fd, read_buf, COMMON_BUFSIZE);
+ if (res < 0)
+ retval = EXIT_FAILURE;
+ if (res <= 0)
+ break;
+ for (i = 0; i < res; i++) {
+ unsigned char c = read_buf[i];
+ char buf[sizeof("M-^c")];
+#if ENABLE_FEATURE_CATN
+ if (eol_seen && c != skip_num_on)
+ printf("%6u ", ++lineno);
+ eol_seen = (c == eol_char);
+#endif
+ visible(c, buf, opts);
+ fputs(buf, stdout);
+ }
+ }
+ if (ENABLE_FEATURE_CLEAN_UP && fd)
+ close(fd);
} while (*++argv);
- return retval;
+ fflush_stdout_and_exit(retval);
}
+#undef CAT_OPT_n
+#undef CAT_OPT_b
+#endif
int cat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int cat_main(int argc, char **argv)
+int cat_main(int argc UNUSED_PARAM, char **argv)
{
- getopt32(argv, "u");
+#if ENABLE_FEATURE_CATV || ENABLE_FEATURE_CATN
+ unsigned opts;
+
+ opts =
+#endif
+ getopt32(argv, IF_FEATURE_CATV("^")
+ /* -u is ignored ("unbuffered") */
+ IF_FEATURE_CATV("etvA")IF_FEATURE_CATN("nb")"u"
+ IF_FEATURE_CATV("\0" "Aetv" /* -A == -vet */)
+ );
argv += optind;
+
+ /* Read from stdin if there's nothing else to do. */
+ if (!argv[0])
+ *--argv = (char*)"-";
+
+#if ENABLE_FEATURE_CATV
+ if (opts & 7)
+ return catv(opts, argv);
+ opts >>= 4;
+#endif
+
+#if ENABLE_FEATURE_CATN
+# define CAT_OPT_n (1<<0)
+# define CAT_OPT_b (1<<1)
+ if (opts & (CAT_OPT_n|CAT_OPT_b)) { /* -n or -b */
+ struct number_state ns;
+
+ ns.width = 6;
+ ns.start = 1;
+ ns.inc = 1;
+ ns.sep = "\t";
+ ns.empty_str = "\n";
+ ns.all = !(opts & CAT_OPT_b); /* -n without -b */
+ ns.nonempty = (opts & CAT_OPT_b); /* -b (with or without -n) */
+ do {
+ print_numbered_lines(&ns, *argv);
+ } while (*++argv);
+ fflush_stdout_and_exit(EXIT_SUCCESS);
+ }
+ /*opts >>= 2;*/
+#endif
+
return bb_cat(argv);
}