Ports: Add libmpg123 port

Add `libmpg123` port, for dependant projects to be able to use it.

This port doesn't include the entire `mpg123` project, just the
`libmpg123` library.

Ports/AvailablePorts.md

@@ -97,6 +97,7 @@ Please make sure to keep this list up to date when adding and updating ports. :^
 | [`libmad`](libmad/)                    | libmad                                                          | 0.15.1b                  | https://www.underbit.com/products/mad/                                         |
 | [`libmodplug`](libmodplug/)            | libmodplug                                                      | 0.8.8.5                  | http://modplug-xmms.sourceforge.net/                                           |
 | [`libmpeg2`](libmpeg2/)                | libmpeg2                                                        | 0.5.1                    | https://libmpeg2.sourceforge.io/                                               |
+| [`libmpg123`](libmpg123/)              | libmpg123                                                       | 1.29.3                   | https://www.mpg123.de/                                                         |
 | [`libogg`](libogg/)                    | libogg                                                          | 1.3.5                    | https://github.com/xiph/ogg                                                    |
 | [`liboggz`](liboggz/)                  | liboggz                                                         | 1.1.1                    | https://www.xiph.org/oggz/                                                     |
 | [`libopenal`](libopenal/)              | OpenAL soft                                                     | 1.21.1                   | https://openal-soft.org/                                                       |

Ports/libmpg123/package.sh

@@ -0,0 +1,13 @@
+#!/usr/bin/env -S bash ../.port_include.sh
+port=libmpg123
+version=1.29.3
+useconfigure=true
+workdir=mpg123-${version}
+use_fresh_config_sub=true
+config_sub_path=build/config.sub
+files="https://download.sourceforge.net/project/mpg123/mpg123/${version}/mpg123-${version}.tar.bz2 mpg123-${version}.tar.bz2
+https://download.sourceforge.net/project/mpg123/mpg123/${version}/mpg123-${version}.tar.bz2.sig mpg123-${version}.tar.bz2.sig"
+
+auth_type="sig"
+auth_import_key="D021FF8ECF4BE09719D61A27231C4CBC60D5CAFE"
+auth_opts=("mpg123-${version}.tar.bz2.sig")

Ports/libmpg123/patches/ReadMe.md

@@ -0,0 +1,5 @@
+# Patches for mpg123 on SerenityOS
+
+## `add-serenity-target.patch`
+
+Add `serenity` as a valid target.

Ports/libmpg123/patches/add-serenity-target.patch

@@ -0,0 +1,121 @@
+diff --git a/configure b/configure
+index d3404be..809a412 100755
+--- a/configure
++++ b/configure
+@@ -14826,11 +14826,11 @@ case $host in
+     cpu_type="x86"
+     newoldwritesample=enabled
+   ;;
+-  i686-*-linux*|i686-*-kfreebsd*-gnu)
++  i686-*-linux*|i686-*-kfreebsd*-gnu|i686-*-serenity*)
+     cpu_type="x86"
+     newoldwritesample=enabled
+   ;;
+-  x86_64-*-linux*|x86_64-*-kfreebsd*-gnu)
++  x86_64-*-linux*|x86_64-*-kfreebsd*-gnu|x86_64-*-serenity*)
+     cpu_type="x86-64"
+   ;;
+   *-*-linux*|*-*-kfreebsd*-gnu)
+diff --git a/configure.ac b/configure.ac
+index 3ca8766..383120e 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -709,11 +709,11 @@ case $host in
+     cpu_type="x86"
+     newoldwritesample=enabled
+   ;;
+-  i686-*-linux*|i686-*-kfreebsd*-gnu)
++  i686-*-linux*|i686-*-kfreebsd*-gnu|i686-*-serenity*)
+     cpu_type="x86"
+     newoldwritesample=enabled
+   ;;
+-  x86_64-*-linux*|x86_64-*-kfreebsd*-gnu)
++  x86_64-*-linux*|x86_64-*-kfreebsd*-gnu|x86_64-*-serenity*)
+     cpu_type="x86-64"
+   ;;
+   *-*-linux*|*-*-kfreebsd*-gnu)
+diff --git a/m4/libtool.m4 b/m4/libtool.m4
+index a6d21ae..44d3c98 100644
+--- a/m4/libtool.m4
++++ b/m4/libtool.m4
+@@ -2836,7 +2836,7 @@ linux*android*)
+   ;;
+
+ # This must be glibc/ELF.
+-linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu*)
++linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu* | serenity*)
+   version_type=linux # correct to gnu/linux during the next big refactor
+   need_lib_prefix=no
+   need_version=no
+@@ -3553,7 +3553,7 @@ irix5* | irix6* | nonstopux*)
+   ;;
+
+ # This must be glibc/ELF.
+-linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu*)
++linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu* | serenity*)
+   lt_cv_deplibs_check_method=pass_all
+   ;;
+
+@@ -4372,7 +4372,7 @@ m4_if([$1], [CXX], [
+ 	    ;;
+ 	esac
+ 	;;
+-      linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu*)
++      linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu* | serenity*)
+ 	case $cc_basename in
+ 	  KCC*)
+ 	    # KAI C++ Compiler
+@@ -4696,7 +4696,7 @@ m4_if([$1], [CXX], [
+       _LT_TAGVAR(lt_prog_compiler_static, $1)='-non_shared'
+       ;;
+
+-    linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu*)
++    linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu* | serenity*)
+       case $cc_basename in
+       # old Intel for x86_64, which still supported -KPIC.
+       ecc*)
+@@ -4954,7 +4954,7 @@ m4_if([$1], [CXX], [
+       ;;
+     esac
+     ;;
+-  linux* | k*bsd*-gnu | gnu*)
++  linux* | k*bsd*-gnu | gnu* | serenity*)
+     _LT_TAGVAR(link_all_deplibs, $1)=no
+     ;;
+   *)
+@@ -5019,7 +5019,7 @@ dnl Note also adjust exclude_expsyms for C++ above.
+   openbsd* | bitrig*)
+     with_gnu_ld=no
+     ;;
+-  linux* | k*bsd*-gnu | gnu*)
++  linux* | k*bsd*-gnu | gnu* | serenity*)
+     _LT_TAGVAR(link_all_deplibs, $1)=no
+     ;;
+   esac
+@@ -5197,7 +5197,7 @@ _LT_EOF
+       _LT_TAGVAR(archive_expsym_cmds, $1)='sed "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
+       ;;
+
+-    gnu* | linux* | tpf* | k*bsd*-gnu | kopensolaris*-gnu)
++    gnu* | linux* | tpf* | k*bsd*-gnu | kopensolaris*-gnu | serenity*)
+       tmp_diet=no
+       if test linux-dietlibc = "$host_os"; then
+ 	case $cc_basename in
+@@ -5809,7 +5809,7 @@ _LT_EOF
+       _LT_TAGVAR(link_all_deplibs, $1)=yes
+       ;;
+
+-    linux*)
++    linux* | serenity*)
+       case $cc_basename in
+       tcc*)
+ 	# Fabrice Bellard et al's Tiny C Compiler
+@@ -6952,7 +6952,7 @@ if test yes != "$_lt_caught_CXX_error"; then
+         _LT_TAGVAR(inherit_rpath, $1)=yes
+         ;;
+
+-      linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu*)
++      linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu* | serenity*)
+         case $cc_basename in
+           KCC*)
+ 	    # Kuck and Associates, Inc. (KAI) C++ Compiler