efivar: add musl libc compatibility

Backport patch to get efivar working with musl.

Upstream issue:
https://github.com/rhboot/efivar/issues/202

After commit meta-oe/1582f81805ee3114bc1a44bd5cf52d21f96702ca
fwupd gives an error when trying to build with musl because
efivar is not compatible. This fixes the issue.

(From OE-Core rev: 005b6aba89eaf1b79fdd7565dd028fdd9bbfcc7d)

Signed-off-by: Davide Gardenal <davide.gardenal@huawei.com>
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 185 insertions, 2 deletions

diff --git a/meta/recipes-bsp/efivar/efivar/efisecdb-fix-build-with-musl-libc.patch b/meta/recipes-bsp/efivar/efivar/efisecdb-fix-build-with-musl-libc.patch
new file mode 100644
index 0000000000..ec5b285a06
--- /dev/null
+++ b/meta/recipes-bsp/efivar/efivar/efisecdb-fix-build-with-musl-libc.patch
@@ -0,0 +1,184 @@
+From cece3ffd5be2f8641eb694513f2b73e5eb97ffd3 Mon Sep 17 00:00:00 2001
+From: Natanael Copa <ncopa@alpinelinux.org>
+Date: Fri, 28 Jan 2022 12:13:30 +0100
+Subject: [PATCH] efisecdb: fix build with musl libc
+
+Refactor code to use POSIX atexit(3) instead of the GNU specific
+on_exit(3).
+
+Resolves: #197
+Resolves: #202
+Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
+
+Upstream-Status: Backport
+https://github.com/rhboot/efivar/commit/cece3ffd5be2f8641eb694513f2b73e5eb97ffd3
+
+Signed-off-by: Davide Gardenal <davide.gardenal@huawei.com>
+---
+ src/compiler.h |  2 --
+ src/efisecdb.c | 68 +++++++++++++++++++-------------------------------
+ 2 files changed, 26 insertions(+), 44 deletions(-)
+
+diff --git a/src/compiler.h b/src/compiler.h
+index e2f18f0b..d95fb014 100644
+--- a/src/compiler.h
++++ b/src/compiler.h
+@@ -7,8 +7,6 @@
+ #ifndef COMPILER_H_
+ #define COMPILER_H_
+ 
+-#include <sys/cdefs.h>
+-
+ /* GCC version checking borrowed from glibc. */
+ #if defined(__GNUC__) && defined(__GNUC_MINOR__)
+ #  define GNUC_PREREQ(maj,min) \
+diff --git a/src/efisecdb.c b/src/efisecdb.c
+index f8823737..6bd5ad90 100644
+--- a/src/efisecdb.c
++++ b/src/efisecdb.c
+@@ -25,6 +25,10 @@
+ extern char *optarg;
+ extern int optind, opterr, optopt;
+ 
++static efi_secdb_t *secdb = NULL;
++static list_t infiles;
++static list_t actions;
++
+ struct hash_param {
+        char *name;
+        efi_secdb_type_t algorithm;
+@@ -187,12 +191,11 @@ add_action(list_t *list, action_type_t action_type, const efi_guid_t *owner,
+ }
+ 
+ static void
+-free_actions(int status UNUSED, void *actionsp)
++free_actions(void)
+ {
+-       list_t *actions = (list_t *)actionsp;
+        list_t *pos, *tmp;
+ 
+-       for_each_action_safe(pos, tmp, actions) {
++       for_each_action_safe(pos, tmp, &actions) {
+                action_t *action = list_entry(pos, action_t, list);
+ 
+                list_del(&action->list);
+@@ -202,12 +205,11 @@ free_actions(int status UNUSED, void *actionsp)
+ }
+ 
+ static void
+-free_infiles(int status UNUSED, void *infilesp)
++free_infiles(void)
+ {
+-       list_t *infiles = (list_t *)infilesp;
+        list_t *pos, *tmp;
+ 
+-       for_each_ptr_safe(pos, tmp, infiles) {
++       for_each_ptr_safe(pos, tmp, &infiles) {
+                ptrlist_t *entry = list_entry(pos, ptrlist_t, list);
+ 
+                list_del(&entry->list);
+@@ -216,27 +218,12 @@ free_infiles(int status UNUSED, void *infilesp)
+ }
+ 
+ static void
+-maybe_free_secdb(int status UNUSED, void *voidp)
++maybe_free_secdb(void)
+ {
+-       efi_secdb_t **secdbp = (efi_secdb_t **)voidp;
+-
+-       if (secdbp == NULL || *secdbp == NULL)
++       if (secdb == NULL)
+                return;
+ 
+-       efi_secdb_free(*secdbp);
+-}
+-
+-static void
+-maybe_do_unlink(int status, void *filep)
+-{
+-       char **file = (char **)filep;
+-
+-       if (status == 0)
+-               return;
+-       if (file == NULL || *file == NULL)
+-               return;
+-
+-       unlink(*file);
++       efi_secdb_free(secdb);
+ }
+ 
+ static void
+@@ -323,15 +310,6 @@ parse_input_files(list_t *infiles, char **outfile, efi_secdb_t **secdb,
+        return status;
+ }
+ 
+-/*
+- * These need to be static globals so that they're not on main's stack when
+- * on_exit() fires.
+- */
+-static efi_secdb_t *secdb = NULL;
+-static list_t infiles;
+-static list_t actions;
+-static char *outfile = NULL;
+-
+ int
+ main(int argc, char *argv[])
+ {
+@@ -351,6 +329,7 @@ main(int argc, char *argv[])
+        bool do_sort_data = false;
+        bool sort_descending = false;
+        int status = 0;
++       char *outfile = NULL;
+ 
+        const char sopts[] = ":aAc:dfg:h:i:Lo:rs:t:v?";
+        const struct option lopts[] = {
+@@ -376,10 +355,9 @@ main(int argc, char *argv[])
+        INIT_LIST_HEAD(&infiles);
+        INIT_LIST_HEAD(&actions);
+ 
+-       on_exit(free_actions, &actions);
+-       on_exit(free_infiles, &infiles);
+-       on_exit(maybe_free_secdb, &secdb);
+-       on_exit(maybe_do_unlink, &outfile);
++       atexit(free_actions);
++       atexit(free_infiles);
++       atexit(maybe_free_secdb);
+ 
+        /*
+         * parse the command line.
+@@ -587,24 +565,30 @@ main(int argc, char *argv[])
+        outfd = open(outfile, flags, 0600);
+        if (outfd < 0) {
+                char *tmpoutfile = outfile;
+-               if (errno == EEXIST)
+-                       outfile = NULL;
++               if (errno != EEXIST)
++                       unlink(outfile);
+                err(1, "could not open \"%s\"", tmpoutfile);
+        }
+ 
+        rc = ftruncate(outfd, 0);
+-       if (rc < 0)
++       if (rc < 0) {
++               unlink(outfile);
+                err(1, "could not truncate output file \"%s\"", outfile);
++       }
+ 
+        void *output;
+        size_t size = 0;
+        rc = efi_secdb_realize(secdb, &output, &size);
+-       if (rc < 0)
++       if (rc < 0) {
++               unlink(outfile);
+                secdb_err(1, "could not realize signature list");
++       }
+ 
+        rc = write(outfd, output, size);
+-       if (rc < 0)
++       if (rc < 0) {
++               unlink(outfile);
+                err(1, "could not write signature list");
++       }
+ 
+        close(outfd);
+        xfree(output);
diff --git a/meta/recipes-bsp/efivar/efivar_38.bb b/meta/recipes-bsp/efivar/efivar_38.bb
index 68c4b4b914..53fe20a95b 100644
--- a/meta/recipes-bsp/efivar/efivar_38.bb
+++ b/meta/recipes-bsp/efivar/efivar_38.bb
@@ -10,6 +10,7 @@ COMPATIBLE_HOST = "(i.86|x86_64|arm|aarch64).*-linux"
 SRC_URI = "git://github.com/rhinstaller/efivar.git;branch=main;protocol=https \
            file://0001-docs-do-not-build-efisecdb-manpage.patch \
            file://0001-src-Makefile-build-util.c-separately-for-makeguids.patch \
+           file://efisecdb-fix-build-with-musl-libc.patch \
            "
 SRCREV = "1753149d4176ebfb2b135ac0aaf79340bf0e7a93"
 
@@ -36,5 +37,3 @@ BBCLASSEXTEND = "native"
 RRECOMMENDS:${PN}:class-target = "kernel-module-efivarfs"
 
 CLEANBROKEN = "1"
-# https://github.com/rhboot/efivar/issues/202
-COMPATIBLE_HOST:libc-musl = 'null'