[PATCH] Makefile, seccomp.sh: Fix cross-builds, adjust syscalls list to compiler

[Stefano Brivio <sbrivio@redhat.com>]

Debian cross-building automatic checks:

  http://crossqa.debian.net/src/passt

currently fail because we don't use the right target architecture and
compiler while building the system call lists and resolving their
numbers in seccomp.sh. Pass ARCH and CC to seccomp.sh and use them.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
 Makefile   | 2 +-
 seccomp.sh | 7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index 667ddfb..e5723a7 100644
--- a/Makefile
+++ b/Makefile
@@ -105,7 +105,7 @@ static: FLAGS += -static -DGLIBC_NO_STATIC_NSS
 static: clean all
 
 seccomp.h: seccomp.sh $(PASST_SRCS) $(PASST_HEADERS)
-	@ EXTRA_SYSCALLS="$(EXTRA_SYSCALLS)" ./seccomp.sh $(PASST_SRCS) $(PASST_HEADERS)
+	@ EXTRA_SYSCALLS="$(EXTRA_SYSCALLS)" ARCH="$(TARGET_ARCH)" CC="$(CC)" ./seccomp.sh $(PASST_SRCS) $(PASST_HEADERS)
 
 passt: $(PASST_SRCS) $(HEADERS)
 	$(CC) $(FLAGS) $(CFLAGS) $(CPPFLAGS) $(PASST_SRCS) -o passt $(LDFLAGS)
diff --git a/seccomp.sh b/seccomp.sh
index 31ea8da..b075efd 100755
--- a/seccomp.sh
+++ b/seccomp.sh
@@ -17,6 +17,9 @@ TMP="$(mktemp)"
 IN="$@"
 OUT="seccomp.h"
 
+[ -z "${ARCH}" ] && ARCH="$(uname -m)"
+[ -z "${CC}" ] && CC="cc"
+
 HEADER="/* This file was automatically generated by $(basename ${0}) */
 
 #ifndef AUDIT_ARCH_PPC64LE
@@ -110,7 +113,7 @@ log2() {
 # $1:	Name of syscall
 syscall_nr() {
 	__in="$(printf "#include <asm-generic/unistd.h>\n#include <sys/syscall.h>\n__NR_%s" ${1})"
-	__out="$(echo "${__in}" | cc -E -xc - -o - | tail -1)"
+	__out="$(echo "${__in}" | ${CC} -E -xc - -o - | tail -1)"
 	[ "${__out}" = "__NR_$1" ] && return 1
 
 	# Output might be in the form "(x + y)" (seen on armv6l, armv7l)
@@ -125,7 +128,7 @@ filter() {
 		case ${__c} in
 		*:*)
 			case ${__c} in
-			$(uname -m):*)
+			${ARCH}:*)
 				__arch_match=1
 				__c=${__c##*:}
 				;;
-- 
@@ -17,6 +17,9 @@ TMP="$(mktemp)"
 IN="$@"
 OUT="seccomp.h"
 
+[ -z "${ARCH}" ] && ARCH="$(uname -m)"
+[ -z "${CC}" ] && CC="cc"
+
 HEADER="/* This file was automatically generated by $(basename ${0}) */
 
 #ifndef AUDIT_ARCH_PPC64LE
@@ -110,7 +113,7 @@ log2() {
 # $1:	Name of syscall
 syscall_nr() {
 	__in="$(printf "#include <asm-generic/unistd.h>\n#include <sys/syscall.h>\n__NR_%s" ${1})"
-	__out="$(echo "${__in}" | cc -E -xc - -o - | tail -1)"
+	__out="$(echo "${__in}" | ${CC} -E -xc - -o - | tail -1)"
 	[ "${__out}" = "__NR_$1" ] && return 1
 
 	# Output might be in the form "(x + y)" (seen on armv6l, armv7l)
@@ -125,7 +128,7 @@ filter() {
 		case ${__c} in
 		*:*)
 			case ${__c} in
-			$(uname -m):*)
+			${ARCH}:*)
 				__arch_match=1
 				__c=${__c##*:}
 				;;
-- 
2.39.1