diff options
author | Ludovic Courtès <ludo@gnu.org> | 2018-08-21 22:39:41 +0200 |
---|---|---|
committer | Ludovic Courtès <ludo@gnu.org> | 2018-08-24 18:01:05 +0200 |
commit | 93c333895a4e2dc9baabec8ade60d9d2ac0a91e2 (patch) | |
tree | bcf3902e7435df4334792fa59e5039776ff4bba0 | |
parent | e4297aa8b95cefa32e2595ce58886fc03b0561f7 (diff) | |
download | gnu-guix-93c333895a4e2dc9baabec8ade60d9d2ac0a91e2.tar gnu-guix-93c333895a4e2dc9baabec8ade60d9d2ac0a91e2.tar.gz |
grafts: Add (guix build debug-link) and use it.
Fixes <https://bugs.gnu.org/19973>.
Reported by Mark H Weaver <mhw@netris.org>.
* guix/build/debug-link.scm: New file.
* guix/build/graft.scm (%graft-hooks): New variable.
(graft): Add #:hooks and honor it.
* guix/grafts.scm (graft-derivation/shallow): Add (guix build
debug-link) and (guix elf) to #:modules.
* tests/debug-link.scm: New file.
* Makefile.am (MODULES): Add guix/build/debug-link.scm.
(SCM_TESTS): Add tests/debug-link.scm.
-rw-r--r-- | Makefile.am | 2 | ||||
-rw-r--r-- | guix/build/debug-link.scm | 210 | ||||
-rw-r--r-- | guix/build/graft.scm | 14 | ||||
-rw-r--r-- | guix/grafts.scm | 4 | ||||
-rw-r--r-- | tests/debug-link.scm | 158 |
5 files changed, 385 insertions, 3 deletions
diff --git a/Makefile.am b/Makefile.am index bdf1c63cee..324674a60e 100644 --- a/Makefile.am +++ b/Makefile.am @@ -171,6 +171,7 @@ MODULES = \ guix/build/svn.scm \ guix/build/syscalls.scm \ guix/build/gremlin.scm \ + guix/build/debug-link.scm \ guix/build/emacs-utils.scm \ guix/build/java-utils.scm \ guix/build/lisp-utils.scm \ @@ -363,6 +364,7 @@ SCM_TESTS = \ tests/syscalls.scm \ tests/inferior.scm \ tests/gremlin.scm \ + tests/debug-link.scm \ tests/bournish.scm \ tests/lint.scm \ tests/publish.scm \ diff --git a/guix/build/debug-link.scm b/guix/build/debug-link.scm new file mode 100644 index 0000000000..9167737fb3 --- /dev/null +++ b/guix/build/debug-link.scm @@ -0,0 +1,210 @@ +;;; GNU Guix --- Functional package management for GNU +;;; Copyright © 2018 Ludovic Courtès <ludo@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 (guix build debug-link) + #:use-module (guix elf) + #:use-module ((guix build utils) + #:select (find-files elf-file? make-file-writable)) + #:use-module (rnrs bytevectors) + #:use-module (rnrs io ports) + #:use-module (srfi srfi-1) + #:use-module (system foreign) + #:use-module (ice-9 match) + #:export (debuglink-crc32 + elf-debuglink + set-debuglink-crc + + graft-debug-links)) + +;;; Commentary: +;;; +;;; This module provides tools to deal with '.gnu_debuglink' sections in ELF +;;; files. These sections are created by 'objcopy --add-gnu-debuglink' to +;;; create separate debug files (info "(gdb) Separate Debug Files"). +;;; +;;; The main facility of this module is 'graft-debug-links', which allows us +;;; to update the CRC that appears in '.gnu_debuglink' sections when grafting, +;;; such that separate debug files remain usable after grafting. Failing to +;;; do that, GDB would complain about CRC mismatch---see +;;; <https://bugs.gnu.org/19973>. +;;; +;;; Code: + +(define %crc32-table + ;; CRC table taken from "(gdb) Separate Debug Files". + ;; TODO: Wouldn't it be nice to generate it "from source" with a macro? + #(#x00000000 #x77073096 #xee0e612c #x990951ba #x076dc419 + #x706af48f #xe963a535 #x9e6495a3 #x0edb8832 #x79dcb8a4 + #xe0d5e91e #x97d2d988 #x09b64c2b #x7eb17cbd #xe7b82d07 + #x90bf1d91 #x1db71064 #x6ab020f2 #xf3b97148 #x84be41de + #x1adad47d #x6ddde4eb #xf4d4b551 #x83d385c7 #x136c9856 + #x646ba8c0 #xfd62f97a #x8a65c9ec #x14015c4f #x63066cd9 + #xfa0f3d63 #x8d080df5 #x3b6e20c8 #x4c69105e #xd56041e4 + #xa2677172 #x3c03e4d1 #x4b04d447 #xd20d85fd #xa50ab56b + #x35b5a8fa #x42b2986c #xdbbbc9d6 #xacbcf940 #x32d86ce3 + #x45df5c75 #xdcd60dcf #xabd13d59 #x26d930ac #x51de003a + #xc8d75180 #xbfd06116 #x21b4f4b5 #x56b3c423 #xcfba9599 + #xb8bda50f #x2802b89e #x5f058808 #xc60cd9b2 #xb10be924 + #x2f6f7c87 #x58684c11 #xc1611dab #xb6662d3d #x76dc4190 + #x01db7106 #x98d220bc #xefd5102a #x71b18589 #x06b6b51f + #x9fbfe4a5 #xe8b8d433 #x7807c9a2 #x0f00f934 #x9609a88e + #xe10e9818 #x7f6a0dbb #x086d3d2d #x91646c97 #xe6635c01 + #x6b6b51f4 #x1c6c6162 #x856530d8 #xf262004e #x6c0695ed + #x1b01a57b #x8208f4c1 #xf50fc457 #x65b0d9c6 #x12b7e950 + #x8bbeb8ea #xfcb9887c #x62dd1ddf #x15da2d49 #x8cd37cf3 + #xfbd44c65 #x4db26158 #x3ab551ce #xa3bc0074 #xd4bb30e2 + #x4adfa541 #x3dd895d7 #xa4d1c46d #xd3d6f4fb #x4369e96a + #x346ed9fc #xad678846 #xda60b8d0 #x44042d73 #x33031de5 + #xaa0a4c5f #xdd0d7cc9 #x5005713c #x270241aa #xbe0b1010 + #xc90c2086 #x5768b525 #x206f85b3 #xb966d409 #xce61e49f + #x5edef90e #x29d9c998 #xb0d09822 #xc7d7a8b4 #x59b33d17 + #x2eb40d81 #xb7bd5c3b #xc0ba6cad #xedb88320 #x9abfb3b6 + #x03b6e20c #x74b1d29a #xead54739 #x9dd277af #x04db2615 + #x73dc1683 #xe3630b12 #x94643b84 #x0d6d6a3e #x7a6a5aa8 + #xe40ecf0b #x9309ff9d #x0a00ae27 #x7d079eb1 #xf00f9344 + #x8708a3d2 #x1e01f268 #x6906c2fe #xf762575d #x806567cb + #x196c3671 #x6e6b06e7 #xfed41b76 #x89d32be0 #x10da7a5a + #x67dd4acc #xf9b9df6f #x8ebeeff9 #x17b7be43 #x60b08ed5 + #xd6d6a3e8 #xa1d1937e #x38d8c2c4 #x4fdff252 #xd1bb67f1 + #xa6bc5767 #x3fb506dd #x48b2364b #xd80d2bda #xaf0a1b4c + #x36034af6 #x41047a60 #xdf60efc3 #xa867df55 #x316e8eef + #x4669be79 #xcb61b38c #xbc66831a #x256fd2a0 #x5268e236 + #xcc0c7795 #xbb0b4703 #x220216b9 #x5505262f #xc5ba3bbe + #xb2bd0b28 #x2bb45a92 #x5cb36a04 #xc2d7ffa7 #xb5d0cf31 + #x2cd99e8b #x5bdeae1d #x9b64c2b0 #xec63f226 #x756aa39c + #x026d930a #x9c0906a9 #xeb0e363f #x72076785 #x05005713 + #x95bf4a82 #xe2b87a14 #x7bb12bae #x0cb61b38 #x92d28e9b + #xe5d5be0d #x7cdcefb7 #x0bdbdf21 #x86d3d2d4 #xf1d4e242 + #x68ddb3f8 #x1fda836e #x81be16cd #xf6b9265b #x6fb077e1 + #x18b74777 #x88085ae6 #xff0f6a70 #x66063bca #x11010b5c + #x8f659eff #xf862ae69 #x616bffd3 #x166ccf45 #xa00ae278 + #xd70dd2ee #x4e048354 #x3903b3c2 #xa7672661 #xd06016f7 + #x4969474d #x3e6e77db #xaed16a4a #xd9d65adc #x40df0b66 + #x37d83bf0 #xa9bcae53 #xdebb9ec5 #x47b2cf7f #x30b5ffe9 + #xbdbdf21c #xcabac28a #x53b39330 #x24b4a3a6 #xbad03605 + #xcdd70693 #x54de5729 #x23d967bf #xb3667a2e #xc4614ab8 + #x5d681b02 #x2a6f2b94 #xb40bbe37 #xc30c8ea1 #x5a05df1b + #x2d02ef8d)) + +(define (debuglink-crc32 port) + "Compute the 32-bit CRC used in in '.gnu_debuglink' over the data read from +PORT and return it." ;(info "(gdb) Separate Debug Files") + (let loop ((crc #xffffffff)) + (let ((byte (get-u8 port))) + (if (eof-object? byte) + (logand (lognot crc) #xffffffff) + (let* ((index (logand (logxor crc byte) #xff)) + (lhs (vector-ref %crc32-table index))) + (loop (logxor lhs (ash crc -8)))))))) + +(define (section-contents elf section) ;XXX: copied from linux-modules.scm + "Return the contents of SECTION in ELF as a bytevector." + (let* ((contents (make-bytevector (elf-section-size section)))) + (bytevector-copy! (elf-bytes elf) (elf-section-offset section) + contents 0 + (elf-section-size section)) + contents)) + +(define null-terminated-bytevector->string + (compose pointer->string bytevector->pointer)) + +(define (elf-debuglink elf) + "Return two values: the '.gnu_debuglink' file name of ELF and its CRC. +Return #f for both if ELF lacks a '.gnu_debuglink' section." + (let ((section (elf-section-by-name elf ".gnu_debuglink"))) + (if section + (let ((size (elf-section-size section)) + (bv (section-contents elf section)) + (endianness (elf-byte-order elf))) + (values (null-terminated-bytevector->string bv) + (bytevector-u32-ref bv (- size 4) endianness))) + (values #f #f)))) + +(define (elf-debuglink-crc-offset elf) + "Return the offset of the '.gnu_debuglink' 32-bit CRC, or #f if ELF lacks a +'.gnu_debuglink' section." + (let ((section (elf-section-by-name elf ".gnu_debuglink"))) + (and section + (+ (elf-section-offset section) + (elf-section-size section) + -4)))) + +(define (set-debuglink-crc file debug-file) + "Compute the CRC of DEBUG-FILE and set it as the '.gnu_debuglink' CRC in +FILE." + (let* ((elf (parse-elf (call-with-input-file file get-bytevector-all))) + (offset (elf-debuglink-crc-offset elf))) + (and offset + (let* ((crc (call-with-input-file debug-file debuglink-crc32)) + (bv (make-bytevector 4))) + (bytevector-u32-set! bv 0 crc (elf-byte-order elf)) + (let ((port (open file O_RDWR))) + (set-port-position! port offset) + (put-bytevector port bv) + (close-port port)))))) + + +;;; +;;; Updating debuglink CRC. +;;; + +(define (find-elf-files outputs) + "Return the list of ELF files found in OUTPUTS, a list of top-level store +directories." + (define directories + (append-map (lambda (output) + (list (string-append output "/bin") + (string-append output "/sbin") + (string-append output "/lib") + (string-append output "/libexec"))) + outputs)) + + (append-map (lambda (directory) + (filter elf-file? + (with-error-to-port (%make-void-port "w") + (lambda () + (find-files directory))))) + directories)) + +(define* (graft-debug-links old-outputs new-outputs mapping + #:key (log-port (current-error-port))) + "Update the '.gnu_debuglink' CRCs found in ELF files of NEW-OUTPUTS, +provided NEW-OUTPUTS contains a \"debug\" output, such that those CRCs match +those of the corresponding '.debug' files found in the \"debug\" output. + +This procedure is meant to be used as a \"grafting hook\" by (guix build +graft)." + (match (assoc-ref new-outputs "debug") + (#f #t) ;nothing to do + (debug-directory + (let ((files (find-elf-files (filter-map (match-lambda + (("debug" . _) + #f) + ((name . directory) + directory)) + new-outputs)))) + (for-each (lambda (file) + (let ((debug (string-append debug-directory + "/lib/debug" file ".debug"))) + (when (file-exists? debug) + (format log-port + "updating '.gnu_debuglink' CRC in '~a'~%" + file) + (make-file-writable file) + (set-debuglink-crc file debug)))) + files))))) diff --git a/guix/build/graft.scm b/guix/build/graft.scm index 8d79e8a50e..c119ee71d1 100644 --- a/guix/build/graft.scm +++ b/guix/build/graft.scm @@ -19,6 +19,7 @@ (define-module (guix build graft) #:use-module (guix build utils) + #:use-module (guix build debug-link) #:use-module (rnrs bytevectors) #:use-module (ice-9 vlist) #:use-module (ice-9 match) @@ -322,8 +323,13 @@ file name pairs." #:directories? #t)) (rename-matching-files output mapping)) +(define %graft-hooks + ;; Default list of hooks run after grafting. + (list graft-debug-links)) + (define* (graft old-outputs new-outputs mapping - #:key (log-port (current-output-port))) + #:key (log-port (current-output-port)) + (hooks %graft-hooks)) "Apply the grafts described by MAPPING on OLD-OUTPUTS, leading to NEW-OUTPUTS. MAPPING must be a list of file name pairs; OLD-OUTPUTS and NEW-OUTPUTS are lists of output name/file name pairs." @@ -336,6 +342,10 @@ NEW-OUTPUTS are lists of output name/file name pairs." files)) (match new-outputs (((names . files) ...) - files)))) + files))) + (for-each (lambda (hook) + (hook old-outputs new-outputs mapping + #:log-port log-port)) + hooks)) ;;; graft.scm ends here diff --git a/guix/grafts.scm b/guix/grafts.scm index 4b10b3efd7..f303e925f1 100644 --- a/guix/grafts.scm +++ b/guix/grafts.scm @@ -130,7 +130,9 @@ are not recursively applied to dependencies of DRV." #:system system #:guile-for-build guile #:modules '((guix build graft) - (guix build utils)) + (guix build utils) + (guix build debug-link) + (guix elf)) #:inputs `(,@(map (lambda (out) `("x" ,drv ,out)) outputs) diff --git a/tests/debug-link.scm b/tests/debug-link.scm new file mode 100644 index 0000000000..2dde3cb460 --- /dev/null +++ b/tests/debug-link.scm @@ -0,0 +1,158 @@ +;;; GNU Guix --- Functional package management for GNU +;;; Copyright © 2018 Ludovic Courtès <ludo@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 (test-debug-link) + #:use-module (guix elf) + #:use-module (guix build utils) + #:use-module (guix build debug-link) + #:use-module (guix gexp) + #:use-module (guix store) + #:use-module (guix tests) + #:use-module (guix monads) + #:use-module (guix derivations) + #:use-module (gnu packages bootstrap) + #:use-module (srfi srfi-1) + #:use-module (srfi srfi-26) + #:use-module (srfi srfi-64) + #:use-module (rnrs io ports) + #:use-module (ice-9 match)) + +(define %guile-executable + (match (false-if-exception (readlink "/proc/self/exe")) + ((? string? program) + (and (file-exists? program) (elf-file? program) + program)) + (_ + #f))) + +(define read-elf + (compose parse-elf get-bytevector-all)) + +(define %store + (open-connection-for-tests)) + +(define-syntax-rule (test-assertm name exp) + (test-assert name + (run-with-store %store exp + #:guile-for-build (%guile-for-build)))) + + +(test-begin "debug-link") + +(unless %guile-executable (test-skip 1)) +(test-assert "elf-debuglink" + (let ((elf (call-with-input-file %guile-executable read-elf))) + (match (call-with-values (lambda () (elf-debuglink elf)) list) + ((#f #f) ;no '.gnu_debuglink' section + (pk 'no-debuglink #t)) + (((? string? file) (? integer? crc)) + (string-suffix? ".debug" file))))) + +;; Since we need %BOOTSTRAP-GCC and co., we have to skip the following tests +;; when networking is unreachable because we'd fail to download it. +(unless (network-reachable?) (test-skip 1)) +(test-assertm "elf-debuglink" + ;; Check whether we can compute the CRC just like objcopy, and whether we + ;; can retrieve it. + (let* ((code (plain-file "test.c" "int main () { return 42; }")) + (exp (with-imported-modules '((guix build utils) + (guix build debug-link) + (guix elf)) + #~(begin + (use-modules (guix build utils) + (guix build debug-link) + (guix elf) + (rnrs io ports)) + + (define read-elf + (compose parse-elf get-bytevector-all)) + + (setenv "PATH" (string-join '(#$%bootstrap-gcc + #$%bootstrap-binutils) + "/bin:" 'suffix)) + (invoke "gcc" "-O0" "-g" #$code "-o" "exe") + (copy-file "exe" "exe.debug") + (invoke "strip" "--only-keep-debug" "exe.debug") + (invoke "strip" "--strip-debug" "exe") + (invoke "objcopy" "--add-gnu-debuglink=exe.debug" + "exe") + (call-with-values (lambda () + (elf-debuglink + (call-with-input-file "exe" + read-elf))) + (lambda (file crc) + (call-with-output-file #$output + (lambda (port) + (let ((expected (call-with-input-file "exe.debug" + debuglink-crc32))) + (write (list file (= crc expected)) + port)))))))))) + (mlet* %store-monad ((drv (gexp->derivation "debuglink" exp)) + (x (built-derivations (list drv)))) + (call-with-input-file (derivation->output-path drv) + (lambda (port) + (return (match (read port) + (("exe.debug" #t) #t) + (x (pk 'fail x #f))))))))) + +(unless (network-reachable?) (test-skip 1)) +(test-assertm "set-debuglink-crc" + ;; Check whether 'set-debuglink-crc' successfully updates the CRC. + (let* ((code (plain-file "test.c" "int main () { return 42; }")) + (debug (plain-file "exe.debug" "a")) + (exp (with-imported-modules '((guix build utils) + (guix build debug-link) + (guix elf)) + #~(begin + (use-modules (guix build utils) + (guix build debug-link) + (guix elf) + (rnrs io ports)) + + (define read-elf + (compose parse-elf get-bytevector-all)) + + (setenv "PATH" (string-join '(#$%bootstrap-gcc + #$%bootstrap-binutils) + "/bin:" 'suffix)) + (invoke "gcc" "-O0" "-g" #$code "-o" "exe") + (copy-file "exe" "exe.debug") + (invoke "strip" "--only-keep-debug" "exe.debug") + (invoke "strip" "--strip-debug" "exe") + (invoke "objcopy" "--add-gnu-debuglink=exe.debug" + "exe") + (set-debuglink-crc "exe" #$debug) + (call-with-values (lambda () + (elf-debuglink + (call-with-input-file "exe" + read-elf))) + (lambda (file crc) + (call-with-output-file #$output + (lambda (port) + (write (list file crc) port))))))))) + (mlet* %store-monad ((drv (gexp->derivation "debuglink" exp)) + (x (built-derivations (list drv)))) + (call-with-input-file (derivation->output-path drv) + (lambda (port) + (return (match (read port) + (("exe.debug" crc) + (= crc (debuglink-crc32 (open-input-string "a")))) + (x + (pk 'fail x #f))))))))) + +(test-end "debug-link") |