Fix the build system.

The improvements are:

- use most of the default "Makefile" for standard packaging;
- also use the default ".gitignore" with for the derived assets;
- don't impose so many $CFLAGS on the user.  GCC still needs to be given
  the `-ffreestanding` flag explicitly for us to get a good binary;
- stop using ad-hoc tools/* scripts, and avoid the code-generation
  anti-pattern overall on the build.  Some of the generated files were
  checked-in, and some were removed;
- remove empty files;
- use POSIX make(1) over gmake;
- add fuzz targets;
- partial "install" and "uninstall" targets;
- complete "clean" target.

The shortcomings are:
- only working on x86_64.  More platforms coming soon;
- code is still messy: way too many warnings, GNU/BSD specific
  extensions, inline assembly, and all kinds of unportable code;
- still only works with GCC and GCC-like compilers, and completly fails
  with tcc(1) and cproc(1);
- the `deps.mk` file is being maintained manually.  As I work on the
  source files I'll finish automating its generation with `mkdeps.sh`;
- still seems to be coupled with Linux;
- still is missing tests setup;
- still uses `#include <$NAME.h>` instead of the correct
  `#include "$NAME.h"` form.

The generated libgrovel.a did match the previous lib/libc.a 100%.

1 files changed, 126 insertions, 0 deletions

diff --git a/tools/manpages.sh b/tools/manpages.sh
new file mode 100755
index 00000000..755ff777
--- /dev/null
+++ b/tools/manpages.sh
@@ -0,0 +1,126 @@
+#!/bin/sh
+set -eu
+
+. tools/lib.sh
+
+
+usage() {
+	cat <<-'EOF'
+		Usage:
+		  sh doc/manpages.sh -i|-u -p MANDIR FILE...
+		  sh doc/manpages.sh -h
+	EOF
+}
+
+help() {
+	cat <<-'EOF'
+
+
+		Options:
+		  -i            set ACTION=install
+		  -u            set ACTION=uninstall
+		  -p MANDIR     use $MANDIR as the prefix directory
+		  -h, --help    show this message
+
+
+		Installs/uninstalls manpage files into MANDIR using the original
+		filename as a hint towards which subdirectory to pick: the
+		`prog.ru.1` file is installed under the `man1/` directory
+		hierarchy under the `ru/` language folder.  When then language
+		is `en`, a the toplevel `man1/` gets a symlink to the `en/`
+		language folder:
+
+		  man/
+		    en/
+		      man1/
+		        prog.1
+		    ru/
+		      man1/
+		        prog.1
+		    man1/
+		      prog.1 -> ../en/man1/prog.1
+
+
+		Examples:
+
+		  Install prog.en.1 under `/usr/man`:
+
+		    $ sh doc/manpages.sh -ip/usr/man prog.en.1
+
+
+		  Uninstall all files listed under doc/ from `$PREFIX`:
+
+		    sh doc/manpages.sh -up "$PREFIX" doc/*.[0-9]
+	EOF
+}
+
+
+for flag in "$@"; do
+	case "$flag" in
+		(--)
+			break
+			;;
+		(--help)
+			usage
+			help
+			exit
+			;;
+		(*)
+			;;
+	esac
+done
+
+while getopts 'iup:h' flag; do
+	case "$flag" in
+		(i)
+			ACTION=install
+			;;
+		(u)
+			ACTION=uninstall
+			;;
+		(p)
+			MANDIR="$OPTARG"
+			;;
+		(h)
+			usage
+			help
+			exit
+			;;
+		(*)
+			usage >&2
+			exit 2
+			;;
+	esac
+done
+shift $((OPTIND - 1))
+
+eval "$(assert_arg "${ACTION:-}" '-[iu] for choosing action')"
+eval "$(assert_arg "${MANDIR:-}" '-p MANDIR')"
+eval "$(assert_arg "${1:-}"      'FILE...')"
+
+
+for f in "$@"; do
+	l="$(echo "$f" | awk -F. '{print $(NF-1)}')"
+	n="$(echo "$f" | awk -F. '{print $NF}')"
+	case "$ACTION" in
+		(install)
+			to_name="$(basename "${f%."$l"."$n"}.$n")"
+			mkdir -p "$MANDIR/$l/man$n" "$MANDIR/man$n"
+			cp "$f" "$MANDIR/$l/man$n/$to_name"
+			if [ "$l" = 'en' ]; then
+				ln -fs "../en/man$n/$to_name" \
+					"$MANDIR/man$n/$to_name"
+			fi
+			;;
+		(uninstall)
+			to_name="$(basename "${f%."$l"."$n"}.$n")"
+			rm -f \
+				"$MANDIR/$l/man$n/$to_name" \
+				"$MANDIR/man$n/$to_name"
+			;;
+		(*)
+			echo "Bad ACTION: $ACTION"
+			exit 1
+			;;
+	esac
+done