devt.rb in ffi-libfuse-0.4.1

- old
+ new

@@ -1,9 +1,8 @@
 # frozen_string_literal: true
 
 require 'ffi'
-
 module FFI
   # Calculate major/minor device numbers for use with mknod etc..
   # @see makedev(3)
   module Device
     extend FFI::Library
@@ -25,14 +24,17 @@
     # @!method minor(dev)
     #  @param [Integer] dev
     #  @return [Integer] the minor component of dev
     attach_function :minor, :"#{prefix}minor", [:int], :int
   rescue FFI::NotFoundError
-    case Platform::NAME
-    when 'x86_64-darwin'
-      # From https://github.com/golang/go/issues/8106 these functions are not defined on Darwin.
-      class << self
+
+    class << self
+      # rubocop:disable Naming/MethodParameterName
+      case RUBY_PLATFORM
+      when 'x86_64-darwin'
+        # From https://github.com/golang/go/issues/8106 these functions are not defined on Darwin.
+
         # define	major(x)	((int32_t)(((u_int32_t)(x) >> 24) & 0xff))
         def major(dev)
           (dev >> 24) & 0xff
         end
 
@@ -43,11 +45,35 @@
 
         # define	makedev(x,y) ((dev_t)(((x) << 24) | (y)))
         def makedev(major, minor)
           (major << 24) | minor
         end
+
+      when 'x86_64-linux-musl' # eg alpine linux
+        # #define major(x) \
+        # 	((unsigned)( (((x)>>31>>1) & 0xfffff000) | (((x)>>8) & 0x00000fff) ))
+        def major(x)
+          ((x >> 31 >> 1) & 0xfffff000) | ((x >> 8) & 0x00000fff)
+        end
+
+        # #define minor(x) \
+        # 	((unsigned)( (((x)>>12) & 0xffffff00) | ((x) & 0x000000ff) ))
+        #
+        def minor(x)
+          ((x >> 12) & 0xffffff00) | (x & 0x000000ff)
+        end
+
+        # #define makedev(x,y) ( \
+        #         (((x)&0xfffff000ULL) << 32) | \
+        # 	(((x)&0x00000fffULL) << 8) | \
+        #         (((y)&0xffffff00ULL) << 12) | \
+        # 	(((y)&0x000000ffULL)) )
+        def makedev(x, y)
+          ((x & 0xfffff000) << 32) | ((x & 0x00000fff) << 8) | ((y & 0xffffff00) << 12) | (y & 0x000000ff)
+        end
+      else
+        raise
       end
-    else
-      raise
+      # rubocop:enable Naming/MethodParameterName
     end
   end
 end