nl: new applet; also implement cat -nb (similar functionality to nl)

function                                             old     new   delta
nl_main                                                -     201    +201
print_numbered_lines                                   -     115    +115
cat_main                                              36     149    +113
static.nl_longopts                                     -     106    +106
packed_usage                                       31081   31182    +101
applet_main                                         1488    1492      +4
applet_names                                        2575    2578      +3
applet_suid                                           93      94      +1
applet_install_loc                                   186     187      +1
------------------------------------------------------------------------------
(add/remove: 4/0 grow/shrink: 6/0 up/down: 645/0)             Total: 645 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 139 insertions, 4 deletions

diff --git a/coreutils/cat.c b/coreutils/cat.c
index 65978887e..4169d9516 100644
--- a/coreutils/cat.c
+++ b/coreutils/cat.c
@@ -15,15 +15,31 @@
 
 //applet:IF_CAT(APPLET_NOFORK(cat, cat, BB_DIR_BIN, BB_SUID_DROP, cat))
 
-//kbuild:lib-$(CONFIG_CAT)     += cat.o
+//kbuild:lib-$(CONFIG_CAT) += cat.o
+// For -n:
+//kbuild:lib-$(CONFIG_CAT) += nl.o
 
 /* BB_AUDIT SUSv3 compliant */
 /* http://www.opengroup.org/onlinepubs/007904975/utilities/cat.html */
 
 //usage:#define cat_trivial_usage
-//usage:       "[FILE]..."
+//usage:       "[-n] [FILE]..."
 //usage:#define cat_full_usage "\n\n"
 //usage:       "Concatenate FILEs and print them to stdout"
+//usage:     "\n        -n      Number output lines"
+/*
+  Longopts not implemented yet:
+     --number-nonblank    number nonempty output lines, overrides -n
+     --number             number all output lines
+  Not implemented yet:
+  -A, --show-all           equivalent to -vET
+  -e                       equivalent to -vE
+  -E, --show-ends          display $ at end of each line
+  -s, --squeeze-blank      suppress repeated empty output lines
+  -t                       equivalent to -vT
+  -T, --show-tabs          display TAB characters as ^I
+  -v, --show-nonprinting   use ^ and M- notation, except for LFD and TAB
+*/
 //usage:
 //usage:#define cat_example_usage
 //usage:       "$ cat /proc/uptime\n"
@@ -61,7 +77,26 @@ int bb_cat(char **argv)
 int cat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int cat_main(int argc UNUSED_PARAM, char **argv)
 {
-        getopt32(argv, "u");
+        struct number_state ns;
+        unsigned opt;
+
+        /* -u is ignored */
+        opt = getopt32(argv, "nbu");
         argv += optind;
-        return bb_cat(argv);
+        if (!(opt & 3)) /* no -n or -b */
+                return bb_cat(argv);
+
+        if (!*argv)
+                *--argv = (char*)"-";
+        ns.width = 6;
+        ns.start = 1;
+        ns.inc = 1;
+        ns.sep = "\t";
+        ns.empty_str = "\n";
+        ns.all = !(opt & 2); /* -n without -b */
+        ns.nonempty = (opt & 2); /* -b (with or without -n) */
+        do {
+                print_numbered_lines(&ns, *argv);
+        } while (*++argv);
+        fflush_stdout_and_exit(EXIT_SUCCESS);
 }
diff --git a/coreutils/nl.c b/coreutils/nl.c
new file mode 100644
index 000000000..97931f334
--- /dev/null
+++ b/coreutils/nl.c
@@ -0,0 +1,100 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+//config:config NL
+//config:       bool "nl"
+//config:       default y
+//config:       help
+//config:         nl is used to number lines of files.
+
+//applet:IF_UNIQ(APPLET(nl, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_UNIQ) += nl.o
+
+//usage:#define nl_trivial_usage
+//usage:       "[OPTIONS] [FILE]..."
+//usage:#define nl_full_usage "\n\n"
+//usage:       "Write FILEs to standard output with line numbers added\n"
+//usage:     "\n        -b STYLE        Which lines to number - a: all, t: nonempty, n: none"
+//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^TODO: support "pBRE": number only lines thatmatch regexp BRE"
+////usage:     "\n      -f STYLE        footer lines"
+////usage:     "\n      -h STYLE        header lines"
+////usage:     "\n      -d CC           use CC for separating logical pages"
+//usage:     "\n        -i N            Line number increment"
+////usage:     "\n      -l NUMBER       group of NUMBER empty lines counted as one"
+////usage:     "\n      -n FORMAT       lneft justified, no leading zeros; rn or rz"
+////usage:     "\n      -p              do not reset line numbers at logical pages (huh?)"
+//usage:     "\n        -s STRING       Use STRING as line number separator"
+//usage:     "\n        -v N            Start from N"
+//usage:     "\n        -w N            Width of line numbers"
+
+/* By default, selects -v1 -i1 -l1 -sTAB -w6 -nrn -hn -bt -fn */
+
+#include "libbb.h"
+
+void FAST_FUNC print_numbered_lines(struct number_state *ns, const char *filename)
+{
+        FILE *fp = fopen_or_warn_stdin(filename);
+        unsigned N = ns->start;
+        char *line;
+
+        while ((line = xmalloc_fgetline(fp)) != NULL) {
+                if (ns->all
+                 || (ns->nonempty && line[0])
+                ) {
+                        printf("%*u%s%s\n", ns->width, N, ns->sep, line);
+                        N += ns->inc;
+                } else if (ns->empty_str)
+                        fputs(ns->empty_str, stdout);
+                free(line);
+        }
+
+        fclose(fp);
+}
+
+int nl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int nl_main(int argc UNUSED_PARAM, char **argv)
+{
+        unsigned opt;
+        struct number_state ns;
+        const char *opt_b = "t";
+        enum {
+                OPT_p = (1 << 0),
+        };
+#if ENABLE_LONG_OPTS
+        static const char nl_longopts[] ALIGN1 =
+                "body-numbering\0"      Required_argument "b"
+        //      "footer-numbering\0"    Required_argument "f" - not implemented yet
+        //      "header-numbering\0"    Required_argument "h" - not implemented yet
+        //      "section-delimiter\0"   Required_argument "d" - not implemented yet
+                "line-increment\0"      Required_argument "i"
+        //      "join-blank-lines\0"    Required_argument "l" - not implemented yet
+        //      "number-format\0"       Required_argument "n" - not implemented yet
+                "no-renumber\0"         No_argument       "p" // no-op so far
+                "number-separator\0"    Required_argument "s"
+                "starting-line-number\0"Required_argument "v"
+                "number-width\0"        Required_argument "w"
+        ;
+
+        applet_long_options = nl_longopts;
+#endif
+        ns.width = 6;
+        ns.start = 1;
+        ns.inc = 1;
+        ns.sep = "\t";
+        opt = getopt32(argv, "pw:+s:v:+i:+b:", &ns.width, &ns.sep, &ns.start, &ns.inc, &opt_b);
+        ns.all = (opt_b[0] == 'a');
+        ns.nonempty = (opt_b[0] == 't');
+        ns.empty_str = xasprintf("%*s\n", ns.width + strlen(ns.sep), "");
+
+        argv += optind;
+        if (!*argv)
+                *--argv = (char*)"-";
+
+        do {
+                print_numbered_lines(&ns, *argv);
+        } while (*++argv);
+
+        fflush_stdout_and_exit(EXIT_SUCCESS);
+}