Add RISC-V 64-bit support and builds

Signed-off-by: MichaIng <micha@dietpi.com>

.github/workflows/build.yml

@@ -53,7 +53,7 @@ jobs:
 
     needs: smoke-tests
 
-    container: ghcr.io/pi-hole/ftl-build:v1.23-${{ matrix.arch }}
+    container: ghcr.io/pi-hole/ftl-build:v1.26-${{ matrix.arch }}
 
     strategy:
       fail-fast: false
@@ -81,6 +81,8 @@ jobs:
             bin_name: pihole-FTL-armv8-linux-gnueabihf
           - arch: aarch64
             bin_name: pihole-FTL-aarch64-linux-gnu
+          - arch: riscv64
+            bin_name: pihole-FTL-riscv64-linux-gnu
 
     env:
       CI_ARCH: ${{ matrix.arch }}${{ matrix.arch_extra }}

src/struct_size.c

@@ -29,6 +29,9 @@ int check_one_struct(const char *struct_name, const size_t found_size, const siz
 #elif defined(__arm__)
 	const size_t expected_size = size32;
 	const char *arch = "arm";
+#elif defined(__riscv) && __riscv_xlen == 64
+	const size_t expected_size = size64;
+	const char *arch = "riscv64";
 #else
 	const size_t expected_size = 0;
 	const char *arch = NULL;

test/arch_test.sh

@@ -147,6 +147,12 @@ elif [[ "${CI_ARCH}" == "armv8a" ]]; then
   check_CPU_arch "v8"
   check_FP_arch "VFPv3-D16"
 
+elif [[ "${CI_ARCH}" == "riscv64" ]]; then
+
+  check_machine "ELF64" "RISC-V"
+  check_libs "[libm.so.6] [libc.so.6] [ld-linux-riscv64-lp64d.so.1]"
+  check_file "ELF 64-bit LSB pie executable, UCB RISC-V, RVC, double-float ABI, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv64-lp64d.so.1, for GNU/Linux 4.15.0, with debug_info, not stripped"
+
 else
 
   echo "Invalid job ${CI_ARCH}"