From 54e6788267c0dac43ec9cb234c711eaa73a3d92b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?S=C3=B6ren=20Tempel?= Date: Sun, 17 Sep 2023 17:21:49 +0200 Subject: [PATCH] syscalls: Add support for musl libc. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit allows using Guix on a foreign distro which uses musl libc, for example, Alpine Linux. Usage of musl libc is detected via a new musl-libc? variable using the Guile %host-type. Using the new musl-libc? variable, we can now implement musl-specific quirks. The two compatibility problems I encountered in this regard are that musl dose not export a readdir64 and statfs64 symbol. On musl, these two functions are implemented as CPP macros that expand to readdir/statfs. To workaround that, a case-distinction was added. The existing linux? variable has been modified to return true if the %host-system contains "linux-" in order to ensure it is true for both linux-gnu as well as linux-musl host systems. The patch has been tested on Alpine Linux and is already used for the downstream Guix package shipped in Alpine Linux's package repository. * guix/build/syscalls.scm (musl-libc?): New variable. (linux?): Truth value on any linux system. (statfs, readdir-procedure): Support musl libc. Signed-off-by: Sören Tempel Signed-off-by: Ludovic Courtès Change-Id: Icc4101a062381240f977f4550344bde696513c52 --- guix/build/syscalls.scm | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/guix/build/syscalls.scm b/guix/build/syscalls.scm index d947b010d3..e02ed07cd4 100644 --- a/guix/build/syscalls.scm +++ b/guix/build/syscalls.scm @@ -836,7 +836,8 @@ fdatasync(2) on the underlying file descriptor." (define-syntax fsword ;fsword_t (identifier-syntax long)) -(define linux? (string-contains %host-type "linux-gnu")) +(define musl-libc? (string-contains %host-type "linux-musl")) +(define linux? (string-contains %host-type "linux-")) (define-syntax define-statfs-flags (syntax-rules (linux hurd) @@ -905,7 +906,7 @@ fdatasync(2) on the underlying file descriptor." (spare (array fsword 4))) (define statfs - (let ((proc (syscall->procedure int "statfs64" '(* *)))) + (let ((proc (syscall->procedure int (if musl-libc? "statfs" "statfs64") '(* *)))) (lambda (file) "Return a data structure describing the file system mounted at FILE." @@ -1232,7 +1233,7 @@ system to PUT-OLD." (define (readdir-procedure name-field-offset sizeof-dirent-header read-dirent-header) - (let ((proc (syscall->procedure '* "readdir64" '(*)))) + (let ((proc (syscall->procedure '* (if musl-libc? "readdir" "readdir64") '(*)))) (lambda* (directory #:optional (pointer->string pointer->string/utf-8)) (let ((ptr (proc directory))) (and (not (null-pointer? ptr))