;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013, 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2014, 2015 Mark H Weaver <mhw@netris.org>
;;; Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

(define-module (gnu packages cross-base)
  #:use-module ((guix licenses) #:prefix license:)
  #:use-module (gnu packages)
  #:use-module (gnu packages base)
  #:use-module (gnu packages bash)
  #:use-module (gnu packages gawk)
  #:use-module (gnu packages gcc)
  #:use-module (gnu packages commencement)
  #:use-module (gnu packages compression)
  #:use-module (gnu packages linux)
  #:use-module (gnu packages mingw)
  #:use-module (gnu packages multiprecision)
  #:use-module (guix packages)
  #:use-module (guix download)
  #:use-module (guix utils)
  #:use-module (guix build-system gnu)
  #:use-module (guix build-system trivial)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 match)
  #:export (cross-binutils
            cross-libc
            cross-gcc
            cross-newlib?))

(define %xgcc
  ;; GCC package used as the basis for cross-compilation.  It doesn't have to
  ;; be 'gcc' and can be a specific variant such as 'gcc-4.8'.
  gcc)

(define (cross p target)
  (package (inherit p)
    (name (string-append (package-name p) "-cross-" target))
    (arguments
     (substitute-keyword-arguments (package-arguments p)
       ((#:configure-flags flags)
        `(cons ,(string-append "--target=" target)
               ,flags))))))

(define (package-with-patch original patch)
  "Return package ORIGINAL with PATCH applied."
  (package (inherit original)
    (source (origin (inherit (package-source original))
              (patches (list patch))))))

(define (cross-binutils target)
  "Return a cross-Binutils for TARGET."
  (let ((binutils (package (inherit binutils)
                    (arguments
                     (substitute-keyword-arguments (package-arguments
                                                    binutils)
                       ((#:configure-flags flags)
                        ;; Build with `--with-sysroot' so that ld honors
                        ;; DT_RUNPATH entries when searching for a needed
                        ;; library.  This works because as a side effect
                        ;; `genscripts.sh' sets `USE_LIBPATH=yes', which tells
                        ;; elf32.em to use DT_RUNPATH in its search list.
                        ;; See <http://sourceware.org/ml/binutils/2013-05/msg00312.html>.
                        ;;
                        ;; In theory choosing / as the sysroot could lead ld
                        ;; to pick up native libs instead of target ones.  In
                        ;; practice the RUNPATH of target libs only refers to
                        ;; target libs, not native libs, so this is safe.
                        `(cons "--with-sysroot=/" ,flags)))))))

    ;; For Xtensa, apply Qualcomm's patch.
    (cross (if (string-prefix? "xtensa-" target)
               (package-with-patch binutils
                                   (search-patch
                                    "ath9k-htc-firmware-binutils.patch"))
               binutils)
           target)))

(define (cross-gcc-arguments target libc)
  "Return build system arguments for a cross-gcc for TARGET, using LIBC (which
may be either a libc package or #f.)"
  ;; Set the current target system so that 'glibc-dynamic-linker' returns the
  ;; right name.
  (parameterize ((%current-target-system target))
    ;; Disable stripping as this can break binaries, with object files of
    ;; libgcc.a showing up as having an unknown architecture.  See
    ;; <http://lists.fedoraproject.org/pipermail/arm/2010-August/000663.html>
    ;; for instance.
    (let ((args `(#:strip-binaries? #f
                  ,@(package-arguments %xgcc))))
     (substitute-keyword-arguments args
       ((#:configure-flags flags)
        `(append (list ,(string-append "--target=" target)
                       ,@(if libc
                             `( ;; Disable libcilkrts because it is not
                                ;; ported to GNU/Hurd. 
                               "--disable-libcilkrts")
                             `( ;; Disable features not needed at this stage.
                               "--disable-shared" "--enable-static"
                               "--enable-languages=c,c++"

                               ;; libstdc++ cannot be built at this stage
                               ;; ("Link tests are not allowed after
                               ;; GCC_NO_EXECUTABLES.").
                               "--disable-libstdc++-v3"

                               "--disable-threads" ;libgcc, would need libc
                               "--disable-libatomic"
                               "--disable-libmudflap"
                               "--disable-libgomp"
                               "--disable-libssp"
                               "--disable-libquadmath"
                               "--disable-decimal-float" ;would need libc
                               "--disable-libcilkrts"
                                ))

                       ;; For a newlib (non-glibc) target
                       ,@(if (cross-newlib? target)
                             '("--with-newlib")
                             '()))

                 ,(if libc
                      flags
                      `(remove (cut string-match "--enable-languages.*" <>)
                               ,flags))))
       ((#:make-flags flags)
        (if libc
            `(let ((libc (assoc-ref %build-inputs "libc")))
               ;; FLAGS_FOR_TARGET are needed for the target libraries to receive
               ;; the -Bxxx for the startfiles.
               (cons (string-append "FLAGS_FOR_TARGET=-B" libc "/lib")
                     ,flags))
            flags))
       ((#:phases phases)
        (let ((phases
               `(alist-cons-after
                 'install 'make-cross-binutils-visible
                 (lambda* (#:key outputs inputs #:allow-other-keys)
                   (let* ((out      (assoc-ref outputs "out"))
                          (libexec  (string-append out "/libexec/gcc/"
                                                   ,target))
                          (binutils (string-append
                                     (assoc-ref inputs "binutils-cross")
                                     "/bin/" ,target "-"))
                          (wrapper  (string-append
                                     (assoc-ref inputs "ld-wrapper-cross")
                                     "/bin/" ,target "-ld")))
                     (for-each (lambda (file)
                                 (symlink (string-append binutils file)
                                          (string-append libexec "/"
                                                         file)))
                               '("as" "nm"))
                     (symlink wrapper (string-append libexec "/ld"))
                     #t))
                 (alist-replace
                  'install
                  (lambda _
                    ;; Unlike our 'strip' phase, this will do the right thing
                    ;; for cross-compilers.
                    (zero? (system* "make" "install-strip")))
                  ,phases))))
           (cond
            ((mingw-target? target)
             `(modify-phases ,phases
                (add-before
                 'configure 'set-cross-path
                 (lambda* (#:key inputs #:allow-other-keys)
                   ;; Add the cross mingw headers to CROSS_C_*_INCLUDE_PATH,
                   ;; and remove them from C_*INCLUDE_PATH.
                   (let ((libc (assoc-ref inputs "libc"))
                         (gcc (assoc-ref inputs "gcc")))
                     (define (cross? x)
                       (and libc (string-prefix? libc x)))
                     (if libc
                         (let ((cpath (string-append
                                       libc "/include"
                                       ":" libc "/i686-w64-mingw32/include")))
                           (for-each (cut setenv <> cpath)
                                     '("CROSS_C_INCLUDE_PATH"
                                       "CROSS_CPLUS_INCLUDE_PATH"
                                       "CROSS_OBJC_INCLUDE_PATH"
                                       "CROSS_OBJCPLUS_INCLUDE_PATH")))
                         (let ((mingw-source (assoc-ref inputs "mingw-source"))
                               (mingw-headers
                                (string-append (getcwd) "/mingw-w64-v5.0-rc2/mingw-w64-headers")))
                           (system* "tar" "xf" mingw-source)
                           (copy-file (string-append mingw-headers "/crt/_mingw.h.in")
                                      (string-append mingw-headers "/crt/_mingw.h"))
                           (substitute* (string-append mingw-headers "/crt/_mingw.h")
                             (("@MINGW_HAS_SECURE_API@") "#define MINGW_HAS_SECURE_API 1"))
                           (let ((cpath (string-append
                                         mingw-headers "/include"
                                         ":" mingw-headers "/crt"
                                         ":" mingw-headers "/defaults/include")))
                             (for-each (cut setenv <> cpath)
                                       '("CROSS_C_INCLUDE_PATH"
                                         "CROSS_CPLUS_INCLUDE_PATH"
                                         "CROSS_OBJC_INCLUDE_PATH"
                                         "CROSS_OBJCPLUS_INCLUDE_PATH"
                                         "CROSS_LIBRARY_PATH")))))
                     (when libc
                       (setenv "CROSS_LIBRARY_PATH"
                               (string-append
                                libc "/lib"
                                ":" libc "/i686-w64-mingw32/lib")))
                     (setenv "CPP" (string-append gcc "/bin/cpp"))
                     (for-each
                      (lambda (var)
                        (and=> (getenv var)
                               (lambda (value)
                                 (let* ((path (search-path-as-string->list
                                               value))
                                        (native-path (list->search-path-as-string
                                                      (remove cross? path) ":")))
                                   (setenv var native-path)))))
                      '("C_INCLUDE_PATH"
                        "CPLUS_INCLUDE_PATH"
                        "OBJC_INCLUDE_PATH"
                        "OBJCPLUS_INCLUDE_PATH"
                        "LIBRARY_PATH"))
                     #t)))))
            (libc
              `(alist-cons-before
                'configure 'set-cross-path
                (lambda* (#:key inputs #:allow-other-keys)
                  ;; Add the cross Linux headers to CROSS_C_*_INCLUDE_PATH,
                  ;; and remove them from C_*INCLUDE_PATH.
                  (let ((libc  (assoc-ref inputs "libc"))
                        (linux (assoc-ref inputs "xlinux-headers")))
                    (define (cross? x)
                      ;; Return #t if X is a cross-libc or cross Linux.
                      (or (string-prefix? libc x)
                          (string-prefix? linux x)))
                    (let ((cpath (string-append
                                  libc "/include"
                                  ":" linux "/include")))
                      (for-each (cut setenv <> cpath)
                                '("CROSS_C_INCLUDE_PATH"
                                  "CROSS_CPLUS_INCLUDE_PATH"
                                  "CROSS_OBJC_INCLUDE_PATH"
                                  "CROSS_OBJCPLUS_INCLUDE_PATH")))
                    (setenv "CROSS_LIBRARY_PATH"
                            (string-append libc "/lib"))
                    (for-each
                     (lambda (var)
                       (and=> (getenv var)
                              (lambda (value)
                                (let* ((path (search-path-as-string->list value))
                                       (native-path (list->search-path-as-string
                                                     (remove cross? path) ":")))
                                  (setenv var native-path)))))
                              '("C_INCLUDE_PATH"
                                "CPLUS_INCLUDE_PATH"
                                "OBJC_INCLUDE_PATH"
                                "OBJCPLUS_INCLUDE_PATH"
                                "LIBRARY_PATH"))
                    #t))
                ,phases))
          (else phases))))))))

(define (cross-gcc-patches target)
  "Return GCC patches needed for TARGET."
  (cond ((string-prefix? "xtensa-" target)
         ;; Patch by Qualcomm needed to build the ath9k-htc firmware.
         (search-patches "ath9k-htc-firmware-gcc.patch"))
        ((mingw-target? target)
         (search-patches "gcc-4.9.3-mingw-gthr-default.patch"))
        (else '())))

(define (cross-gcc-snippet target)
  "Return GCC snippet needed for TARGET."
  (cond ((mingw-target? target)
         '(copy-recursively "libstdc++-v3/config/os/mingw32-w64"
                            "libstdc++-v3/config/os/newlib"))
        (else '())))

(define* (cross-gcc target
                    #:optional (xbinutils (cross-binutils target)) (libc #f))
  "Return a cross-compiler for TARGET, where TARGET is a GNU triplet.  Use
XBINUTILS as the associated cross-Binutils.  If LIBC is false, then build a
GCC that does not target a libc; otherwise, target that libc."
  (package (inherit %xgcc)
    (name (string-append "gcc-cross-"
                         (if libc "" "sans-libc-")
                         target))
    (source (origin (inherit (package-source %xgcc))
              (patches
               (append
                (origin-patches (package-source %xgcc))
                (cons (search-patch "gcc-cross-environment-variables.patch")
                      (cross-gcc-patches target))))
              (modules '((guix build utils)))
              (snippet
               (cross-gcc-snippet target))))

    ;; For simplicity, use a single output.  Otherwise libgcc_s & co. are not
    ;; found by default, etc.
    (outputs '("out"))

    (arguments
     `(#:implicit-inputs? #f
       #:modules ((guix build gnu-build-system)
                  (guix build utils)
                  (ice-9 regex)
                  (srfi srfi-1)
                  (srfi srfi-26))

       ,@(cross-gcc-arguments target libc)))

    (native-inputs
     `(("ld-wrapper-cross" ,(make-ld-wrapper
                             (string-append "ld-wrapper-" target)
                             #:target target
                             #:binutils xbinutils))
       ("binutils-cross" ,xbinutils)
       ("gcc" ,gcc)

       ;; Call it differently so that the builder can check whether the "libc"
       ;; input is #f.
       ("libc-native" ,@(assoc-ref %final-inputs "libc"))

       ;; Remaining inputs.
       ,@(let ((inputs (append (package-inputs %xgcc)
                               (alist-delete "libc" %final-inputs))))
           (cond
            ((mingw-target? target)
             (if libc
                 `(("libc" ,mingw-w64)
                   ,@inputs)
                 `(("mingw-source" ,(package-source mingw-w64))
                   ,@inputs)))
            (libc
               `(("libc" ,libc)
                 ("xlinux-headers"                ;the target headers
                  ,@(assoc-ref (package-propagated-inputs libc)
                               "linux-headers"))
               ,@inputs))
            (else inputs)))))

    (inputs '())

    ;; Only search target inputs, not host inputs.
    (search-paths
     (list (search-path-specification
            (variable "CROSS_C_INCLUDE_PATH")
            (files '("include")))
           (search-path-specification
            (variable "CROSS_CPLUS_INCLUDE_PATH")
            (files '("include")))
           (search-path-specification
            (variable "CROSS_OBJC_INCLUDE_PATH")
            (files '("include")))
           (search-path-specification
            (variable "CROSS_OBJCPLUS_INCLUDE_PATH")
            (files '("include")))
           (search-path-specification
            (variable "CROSS_LIBRARY_PATH")
            (files '("lib" "lib64")))))
    (native-search-paths '())))

(define* (cross-libc target
                     #:optional
                     (xgcc (cross-gcc target))
                     (xbinutils (cross-binutils target)))
  "Return a libc cross-built for TARGET, a GNU triplet.  Use XGCC and
XBINUTILS and the cross tool chain."
  (cond
   ((cross-newlib? target)
    (cross-newlib? target))
   (else
    (let ((xlinux-headers
           (package (inherit linux-libre-headers)
             (name (string-append (package-name linux-libre-headers)
                                  "-cross-" target))
             (arguments
              (substitute-keyword-arguments
                  `(#:implicit-cross-inputs? #f
                    ,@(package-arguments linux-libre-headers))
                ((#:phases phases)
                 `(alist-replace
                   'build
                   (lambda _
                     (setenv "ARCH" ,(system->linux-architecture target))
                     (format #t "`ARCH' set to `~a' (cross compiling)~%"
                             (getenv "ARCH"))

                     (and (zero? (system* "make" "defconfig"))
                          (zero? (system* "make" "mrproper" "headers_check"))))
                   ,phases))))
             (native-inputs `(("cross-gcc" ,xgcc)
                              ("cross-binutils" ,xbinutils)
                              ,@(package-native-inputs linux-libre-headers))))))
      (package (inherit glibc)
        (name (string-append "glibc-cross-" target))
        (arguments
         (substitute-keyword-arguments
             `(;; Disable stripping (see above.)
               #:strip-binaries? #f

               ;; This package is used as a target input, but it should not have
               ;; the usual cross-compilation inputs since that would include
               ;; itself.
               #:implicit-cross-inputs? #f

               ,@(package-arguments glibc))
           ((#:configure-flags flags)
            `(cons ,(string-append "--host=" target)
                   ,flags))
           ((#:phases phases)
            `(alist-cons-before
              'configure 'set-cross-linux-headers-path
              (lambda* (#:key inputs #:allow-other-keys)
                (let* ((linux (assoc-ref inputs "linux-headers"))
                       (cpath (string-append linux "/include")))
                  (for-each (cut setenv <> cpath)
                            '("CROSS_C_INCLUDE_PATH"
                              "CROSS_CPLUS_INCLUDE_PATH"
                              "CROSS_OBJC_INCLUDE_PATH"
                              "CROSS_OBJCPLUS_INCLUDE_PATH"))              
                  #t))
              ,phases))))

        ;; Shadow the native "linux-headers" because glibc's recipe expects the
        ;; "linux-headers" input to point to the right thing.
        (propagated-inputs `(("linux-headers" ,xlinux-headers)))

        ;; FIXME: 'static-bash' should really be an input, not a native input,
        ;; but to do that will require building an intermediate cross libc.
        (inputs '())

        (native-inputs `(("cross-gcc" ,xgcc)
                         ("cross-binutils" ,xbinutils)
                         ,@(package-inputs glibc)     ;FIXME: static-bash
                         ,@(package-native-inputs glibc))))))))

(define (native-libc target)
  (if (mingw-target? target)
      mingw-w64
      glibc))

(define (cross-newlib? target)
  (and (not (eq? (native-libc target) glibc))
       (native-libc target)))


;;;
;;; Concrete cross toolchains.
;;;

(define-public xgcc-mips64el
  (let* ((triplet "mips64el-linux-gnuabi64")      ;N64 ABI
         (xgcc    (cross-gcc triplet
                             (cross-binutils triplet)
                             (cross-libc triplet))))
    ;; Don't attempt to build this cross-compiler on i686;
    ;; see <http://bugs.gnu.org/19598>.
    (package (inherit xgcc)
      (supported-systems (fold delete
                               (package-supported-systems xgcc)
                               '("mips64el-linux" "i686-linux"))))))

(define-public xgcc-avr
  ;; AVR cross-compiler, used to build AVR-Libc.
  (let ((triplet "avr"))
    (cross-gcc triplet
               (cross-binutils triplet))))

(define-public xgcc-xtensa
  ;; Bare-bones Xtensa cross-compiler, used to build the Atheros firmware.
  (cross-gcc "xtensa-elf"))

(define-public xgcc-armhf
  (let* ((triplet "arm-linux-gnueabihf")
         (xgcc    (cross-gcc triplet
                             (cross-binutils triplet)
                             (cross-libc triplet))))
    (package (inherit xgcc)
      (supported-systems (delete "armhf-linux" %supported-systems)))))

;; (define-public xgcc-armel
;;   (let ((triplet "armel-linux-gnueabi"))
;;     (cross-gcc triplet
;;                (cross-binutils triplet)
;;                (cross-libc triplet))))

(define-public xgcc-sans-libc-i686-w64-mingw32
  (let ((triplet "i686-w64-mingw32"))
    (cross-gcc triplet
               (cross-binutils triplet))))

(define-public xbinutils-i686-w64-mingw32
  (let ((triplet "i686-w64-mingw32"))
    (cross-binutils triplet)))

(define-public xgcc-i686-w64-mingw32
  (let ((triplet "i686-w64-mingw32"))
    (cross-gcc triplet
               (cross-binutils triplet)
               (cross-newlib? triplet))))