krata: rework cross-compilation

hack/build/cargo.sh

@@ -3,11 +3,22 @@ set -e
 
 TOOLS_DIR="$(dirname "${0}")"
 RUST_TARGET="$("${TOOLS_DIR}/target.sh")"
+CROSS_COMPILE="$("${TOOLS_DIR}/cross-compile.sh")"
 
-if [ "${RUST_LIBC}" = "musl" ] && [ -f "/etc/alpine-release" ]
+if [ "${TARGET_LIBC}" = "musl" ] && [ -f "/etc/alpine-release" ]
 then
   export RUSTFLAGS="-Ctarget-feature=-crt-static"
 fi
 
+if [ -z "${CARGO}" ]
+then
+  if [ "${CROSS_COMPILE}" = "1" ] && command -v cross > /dev/null
+  then
+    CARGO="cross"
+  else
+    CARGO="cargo"
+  fi
+fi
+
 export CARGO_BUILD_TARGET="${RUST_TARGET}"
-exec cargo "${@}"
+exec "${CARGO}" "${@}"

hack/build/cross-compile.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+set -e
+
+TOOLS_DIR="$(dirname "${0}")"
+
+RUST_TARGET="$("${TOOLS_DIR}/target.sh")"
+TARGET_ARCH="$(echo "${RUST_TARGET}" | awk -F '-' '{print $1}')"
+HOST_ARCH="$(uname -m)"
+
+if [ "${HOST_ARCH}" != "${TARGET_ARCH}" ]
+then
+  echo "1"
+else
+  echo "0"
+fi

hack/build/target.sh

@@ -1,29 +1,57 @@
 #!/bin/sh
 set -e
 
-if [ -z "${RUST_LIBC}" ]
+if [ -z "${TARGET_LIBC}" ] || [ "${KRATA_TARGET_IGNORE_LIBC}" = "1" ]
 then
-  RUST_LIBC="gnu"
+  TARGET_LIBC="gnu"
+fi
+
+if [ -z "${TARGET_ARCH}" ]
+then
+  TARGET_ARCH="$(uname -m)"
 fi
 
 if [ -z "${RUST_TARGET}" ]
 then
-  HOST_ARCH="$(uname -m)"
-  if [ "${HOST_ARCH}" = "x86_64" ]
+  if [ "${TARGET_ARCH}" = "x86_64" ]
   then
-    RUST_TARGET="x86_64-unknown-linux-${RUST_LIBC}"
+    RUST_TARGET="x86_64-unknown-linux-${TARGET_LIBC}"
   fi
 
-  if [ "${HOST_ARCH}" = "aarch64" ]
+  if [ "${TARGET_ARCH}" = "aarch64" ]
   then
-    RUST_TARGET="aarch64-unknown-linux-${RUST_LIBC}"
+    RUST_TARGET="aarch64-unknown-linux-${TARGET_LIBC}"
   fi
 fi
 
-if [ -z "${RUST_TARGET}" ]
+if [ -z "${C_TARGET}" ]
 then
-  echo "ERROR: Unable to determine RUST_TARGET, your architecture may not be supported by krata." > /dev/stderr
-  exit 1
+  if [ "${TARGET_ARCH}" = "x86_64" ]
+  then
+    C_TARGET="x86_64-linux-${TARGET_LIBC}"
+  fi
+
+  if [ "${TARGET_ARCH}" = "aarch64" ]
+  then
+    C_TARGET="aarch64-linux-${TARGET_LIBC}"
+  fi
 fi
 
-echo "${RUST_TARGET}"
+if [ "${KRATA_TARGET_C_MODE}" = "1" ]
+then
+  if [ -z "${C_TARGET}" ]
+  then
+    echo "ERROR: Unable to determine C_TARGET, your architecture may not be supported by krata." > /dev/stderr
+    exit 1
+  fi
+
+  echo "${C_TARGET}"
+else
+  if [ -z "${RUST_TARGET}" ]
+  then
+    echo "ERROR: Unable to determine RUST_TARGET, your architecture may not be supported by krata." > /dev/stderr
+    exit 1
+  fi
+
+  echo "${RUST_TARGET}"
+fi