2018-03-06 15:07:00

1 files changed, 39 insertions, 18 deletions

diff --git a/tex/context/base/mkiv/util-fil.lua b/tex/context/base/mkiv/util-fil.lua
index b44dbc3fe..0e8ed4e57 100644
--- a/tex/context/base/mkiv/util-fil.lua
+++ b/tex/context/base/mkiv/util-fil.lua
@@ -6,11 +6,8 @@ if not modules then modules = { } end modules ['util-fil'] = {
     license   = "see context related readme files"
 }
 
-local byte    = string.byte
-local char    = string.char
-local extract = bit32.extract
-local rshift  = bit32.rshift
-local band    = bit32.band
+local byte = string.byte
+local char = string.char
 
 -- Here are a few helpers (the starting point were old ones I used for parsing
 -- flac files). In Lua 5.3 we can probably do this better. Some code will move
@@ -239,15 +236,22 @@ end
 
 -- (real) ((n<<16)>>(16+14)) + ((n&0x3fff)/16384.0))
 
-function files.read2dot14(f)
-    local a, b = byte(f:read(2),1,2)
-    if a >= 0x80 then
-        local n = -(0x100 * a + b)
-        return - (extract(n,14,2) + (band(n,0x3FFF) / 16384.0))
-    else
-        local n =   0x100 * a + b
-        return   (extract(n,14,2) + (band(n,0x3FFF) / 16384.0))
+if bit32 then
+
+    local extract = bit32.extract
+    local band    = bit32.band
+
+    function files.read2dot14(f)
+        local a, b = byte(f:read(2),1,2)
+        if a >= 0x80 then
+            local n = -(0x100 * a + b)
+            return - (extract(n,14,2) + (band(n,0x3FFF) / 16384.0))
+        else
+            local n =   0x100 * a + b
+            return   (extract(n,14,2) + (band(n,0x3FFF) / 16384.0))
+        end
     end
+
 end
 
 function files.skipshort(f,n)
@@ -260,11 +264,28 @@ end
 
 -- writers (kind of slow)
 
-function files.writecardinal2(f,n)
-    local a = char(n % 256)
-    n = rshift(n,8)
-    local b = char(n % 256)
-    f:write(b,a)
+if bit32 then
+
+    local rshift  = bit32.rshift
+
+    function files.writecardinal2(f,n)
+        local a = char(n % 256)
+        n = rshift(n,8)
+        local b = char(n % 256)
+        f:write(b,a)
+    end
+
+else
+
+    local floor = math.floor
+
+    function files.writecardinal2(f,n)
+        local a = char(n % 256)
+        n = floor(n/256)
+        local b = char(n % 256)
+        f:write(b,a)
+    end
+
 end
 
 function files.writecardinal4(f,n)