From b1d478defc7f3e794974be2b9665cd4a58030569 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?S=C3=B6ren=20Tempel?= Date: Thu, 14 Sep 2023 12:35:38 +0000 Subject: [PATCH] syscalls: Add support for musl libc 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. * guix/build/syscalls.scm (linux?): Truth value on any linux system. * guix/build/syscalls.scm (readdir-procedure): Support musl libc. * guix/build/syscalls.scm (statfs): Support musl libc. --- 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 c9c0bf594d..b845b8aab9 100644 --- a/guix/build/syscalls.scm +++ b/guix/build/syscalls.scm @@ -836,7 +836,8 @@ (define-record-type (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 @@ (define-c-struct %statfs ; (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 @@ (define closedir* (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))