build: don't hardcode num worker threads "make -j4"

contrib/build-linux/appimage/make_appimage.sh

@@ -61,7 +61,7 @@ tar xf "$CACHEDIR/Python-$PYTHON_VERSION.tar.xz" -C "$CACHEDIR"
         --enable-ipv6 \
         --enable-shared \
         -q
-    make -j4 -s || fail "Could not build Python"
+    make "-j$CPU_COUNT" -s || fail "Could not build Python"
 )
 info "installing python."
 (
@@ -111,7 +111,7 @@ XCB_UTIL_VERSION="acf790d7752f36e450d476ad79807d4012ec863b"
     git checkout "${XCB_UTIL_VERSION}^{commit}"
     ./autogen.sh
     ./configure --enable-shared
-    make -j4 -s || fail "Could not build libxcb-util1"
+    make "-j$CPU_COUNT" -s || fail "Could not build libxcb-util1"
 ) || fail "Could build libxcb-util1"
 cp "$CACHEDIR/libxcb-util1/util/src/.libs/libxcb-util.so.1" "$APPDIR/usr/lib/libxcb-util.so.1"
 

contrib/build_tools_util.sh

@@ -129,6 +129,7 @@ if [ -n "$GCC_TRIPLET_BUILD" ] ; then
 fi
 
 export GCC_STRIP_BINARIES="${GCC_STRIP_BINARIES:-0}"
+export CPU_COUNT="$(nproc 2> /dev/null || sysctl -n hw.ncpu)"
 
 
 function break_legacy_easy_install() {

contrib/make_libsecp256k1.sh

@@ -59,7 +59,7 @@ info "Building $pkgname..."
             --disable-static \
             --enable-shared || fail "Could not configure $pkgname. Please make sure you have a C compiler installed and try again."
     fi
-    make -j4 || fail "Could not build $pkgname"
+    make "-j$CPU_COUNT" || fail "Could not build $pkgname"
     make install || fail "Could not install $pkgname"
     . "$here/$pkgname/dist/lib/libsecp256k1.la"
     host_strip "$here/$pkgname/dist/lib/$dlname"

contrib/make_libusb.sh

@@ -47,7 +47,7 @@ info "Building $pkgname..."
             $AUTOCONF_FLAGS \
             || fail "Could not configure $pkgname. Please make sure you have a C compiler installed and try again."
     fi
-    make -j4 || fail "Could not build $pkgname"
+    make "-j$CPU_COUNT" || fail "Could not build $pkgname"
     make install || warn "Could not install $pkgname"
     . "$here/$pkgname/libusb/.libs/libusb-1.0.la"
     host_strip "$here/$pkgname/libusb/.libs/$dlname"

contrib/make_zbar.sh

@@ -81,7 +81,7 @@ info "Building $pkgname..."
             --disable-static \
             --enable-shared || fail "Could not configure $pkgname. Please make sure you have a C compiler installed and try again."
     fi
-    make -j4 || fail "Could not build $pkgname"
+    make "-j$CPU_COUNT" || fail "Could not build $pkgname"
     make install || fail "Could not install $pkgname"
     . "$here/$pkgname/dist/lib/libzbar.la"
     host_strip "$here/$pkgname/dist/lib/$dlname"