1 files changed, 156 insertions, 0 deletions
diff --git a/ext/fiddle/lib/fiddle/cparser.rb b/ext/fiddle/lib/fiddle/cparser.rb
new file mode 100644
index 0000000000..ede88ae668
--- /dev/null
+++ b/ext/fiddle/lib/fiddle/cparser.rb
@@ -0,0 +1,156 @@
+module Fiddle
+  # Methods for parsing C struct and C prototype signatures.
+  module CParser
+    # Parses a C struct's members
+    #
+    # Example:
+    #
+    #   parse_struct_signature(['int i', 'char c'])
+    #   => [[Fiddle::TYPE_INT, Fiddle::TYPE_CHAR], ["i", "c"]]
+    #
+    def parse_struct_signature(signature, tymap=nil)
+      if( signature.is_a?(String) )
+        signature = signature.split(/\s*,\s*/)
+      end
+      mems = []
+      tys  = []
+      signature.each{|msig|
+        tks = msig.split(/\s+(\*)?/)
+        ty = tks[0..-2].join(" ")
+        member = tks[-1]
+
+        case ty
+        when /\[(\d+)\]/
+          n = $1.to_i
+          ty.gsub!(/\s*\[\d+\]/,"")
+          ty = [ty, n]
+        when /\[\]/
+          ty.gsub!(/\s*\[\]/, "*")
+        end
+
+        case member
+        when /\[(\d+)\]/
+          ty = [ty, $1.to_i]
+          member.gsub!(/\s*\[\d+\]/,"")
+        when /\[\]/
+          ty = ty + "*"
+          member.gsub!(/\s*\[\]/, "")
+        end
+
+        mems.push(member)
+        tys.push(parse_ctype(ty,tymap))
+      }
+      return tys, mems
+    end
+
+    # Parses a C prototype signature
+    #
+    # Example:
+    #
+    #   include Fiddle::CParser
+    #   => Object
+    #
+    #   parse_signature('double sum(double, double)')
+    #   => ["sum", Fiddle::TYPE_DOUBLE, [Fiddle::TYPE_DOUBLE, Fiddle::TYPE_DOUBLE]]
+    #
+    def parse_signature(signature, tymap=nil)
+      tymap ||= {}
+      signature = signature.gsub(/\s+/, " ").strip
+      case signature
+      when /^([\w@\*\s]+)\(([\w\*\s\,\[\]]*)\)$/
+        ret = $1
+        (args = $2).strip!
+        ret = ret.split(/\s+/)
+        args = args.split(/\s*,\s*/)
+        func = ret.pop
+        if( func =~ /^\*/ )
+          func.gsub!(/^\*+/,"")
+          ret.push("*")
+        end
+        ret  = ret.join(" ")
+        return [func, parse_ctype(ret, tymap), args.collect{|arg| parse_ctype(arg, tymap)}]
+      else
+        raise(RuntimeError,"can't parse the function prototype: #{signature}")
+      end
+    end
+
+    # Given a String of C type +ty+, return the corresponding DL constant.
+    #
+    # +ty+ can also accept an Array of C type Strings, and will returned in a
+    # corresponding Array.
+    #
+    # If Hash +tymap+ is provided, +ty+ is expected to be the key, and the
+    # value will be the C type to be looked up.
+    #
+    # Example:
+    #
+    #   parse_ctype('int')
+    #   => Fiddle::TYPE_INT
+    #
+    #   parse_ctype('double')
+    #   => Fiddle::TYPE_DOUBLE
+    #
+    #   parse_ctype('unsigned char')
+    #   => -Fiddle::TYPE_CHAR
+    #
+    def parse_ctype(ty, tymap=nil)
+      tymap ||= {}
+      case ty
+      when Array
+        return [parse_ctype(ty[0], tymap), ty[1]]
+      when "void"
+        return TYPE_VOID
+      when "char"
+        return TYPE_CHAR
+      when "unsigned char"
+        return  -TYPE_CHAR
+      when "short"
+        return TYPE_SHORT
+      when "unsigned short"
+        return -TYPE_SHORT
+      when "int"
+        return TYPE_INT
+      when "unsigned int", 'uint'
+        return -TYPE_INT
+      when "long"
+        return TYPE_LONG
+      when "unsigned long"
+        return -TYPE_LONG
+      when "long long"
+        if( defined?(TYPE_LONG_LONG) )
+          return TYPE_LONG_LONG
+        else
+          raise(RuntimeError, "unsupported type: #{ty}")
+        end
+      when "unsigned long long"
+        if( defined?(TYPE_LONG_LONG) )
+          return -TYPE_LONG_LONG
+        else
+          raise(RuntimeError, "unsupported type: #{ty}")
+        end
+      when "float"
+        return TYPE_FLOAT
+      when "double"
+        return TYPE_DOUBLE
+      when "size_t"
+        return TYPE_SIZE_T
+      when "ssize_t"
+        return TYPE_SSIZE_T
+      when "ptrdiff_t"
+        return TYPE_PTRDIFF_T
+      when "intptr_t"
+        return TYPE_INTPTR_T
+      when "uintptr_t"
+        return TYPE_UINTPTR_T
+      when /\*/, /\[\s*\]/
+        return TYPE_VOIDP
+      else
+        if( tymap[ty] )
+          return parse_ctype(tymap[ty], tymap)
+        else
+          raise(DLError, "unknown type: #{ty}")
+        end
+      end
+    end
+  end
+end