stable 2007.08.07 01:37

1 files changed, 157 insertions, 0 deletions

diff --git a/tex/context/base/luat-iop.lua b/tex/context/base/luat-iop.lua
new file mode 100644
index 000000000..469b7c034
--- /dev/null
+++ b/tex/context/base/luat-iop.lua
@@ -0,0 +1,157 @@
+-- filename : luat-iop.lua
+-- comment  : companion to luat-lib.tex
+-- author   : Hans Hagen, PRAGMA-ADE, Hasselt NL
+-- copyright: PRAGMA ADE / ConTeXt Development Team
+-- license  : see context related readme files
+
+-- this paranoid stuff in web2c ... we cannot hook checks into the
+-- input functions because one can always change the callback but
+-- we can feed back specific patterns and paths into the next
+-- mechanism
+
+if not versions  then versions = { } end versions['luat-exe'] = 1.001
+
+if not io.inp then io.inp = { } end
+if not io.out then io.out = { } end
+
+io.inp.blocked      = { }
+io.out.blocked      = { }
+io.inp.permitted    = { }
+io.out.permitted    = { }
+io.inp.modes        = { } -- functions
+io.out.modes        = { } -- functions
+
+io.blocked_openers  = { } -- *.open(name,method)
+
+function io.inp.inhibit  (name) table.insert(io.inp.blocked,   name) end
+function io.out.inhibit  (name) table.insert(io.out.blocked,   name) end
+function io.inp.permit   (name) table.insert(io.inp.permitted, name) end
+function io.out.permit   (name) table.insert(io.out.permitted, name) end
+
+function io.register_opener(func) table.insert(io.blocked_openers,   func) end
+
+function io.finalize_openers(func)
+    if (#io.out.blocked > 0) or (#io.inp.blocked > 0) then
+        do
+            local open          = func
+            local out_permitted = io.out.permitted
+            local inp_permitted = io.inp.permitted
+            local out_blocked   = io.out.blocked
+            local inp_blocked   = io.inp.blocked
+            return function(name,method)
+                local function checked(blocked, permitted)
+                    local n = string.lower(name)
+                    for _,b in pairs(blocked) do
+                        if string.find(n,b) then
+                            for _,p in pairs(permitted) do
+                                if string.find(n,p) then
+                                    return true
+                                end
+                            end
+                            return false
+                        end
+                    end
+                    return true
+                end
+                if method and string.find(method,'[wa]') then
+                    if #out.blocked > 0 then
+                        if not checked(out_blocked, out_permitted) then
+                            -- print("writing to " .. name .. " is not permitted")
+                            return nil
+                        end
+                    end
+                else
+                    if #inp.blocked > 0 then
+                        if not checked(inp_blocked, inp_permitted) then
+                            -- print("reading from " .. name .. " is not permitted")
+                            return nil
+                        end
+                    end
+                end
+                return open(name,method)
+            end
+        end
+    else
+        return func
+    end
+end
+
+--~ io.inp.inhibit('^%.')
+--~ io.inp.inhibit('^/etc')
+--~ io.inp.inhibit('/windows/')
+--~ io.inp.inhibit('/winnt/')
+--~ io.inp.permit('c:/windows/wmsetup.log')
+
+--~ io.open = io.finalize_openers(io.open)
+
+--~ f = io.open('.tex')                   print(f)
+--~ f = io.open('tufte.tex')              print(f)
+--~ f = io.open('t:/sources/tufte.tex')   print(f)
+--~ f = io.open('/etc/passwd')            print(f)
+--~ f = io.open('c:/windows/crap.log')    print(f)
+--~ f = io.open('c:/windows/wmsetup.log') print(f)
+
+function io.set_opener_modes(i,o)
+    for _,v in pairs({'inp','out'}) do
+        if io[v][i] then
+            io[v][i]()
+        elseif io[v][string.sub(i,1,1)] then
+            io[v][string.sub(i,1,1)]()
+        end
+    end
+    io.open = io.finalize_openers(io.open)
+end
+
+function io.set_opener_modes(i,o)
+    local f
+    for _,v in pairs({'inp','out'}) do
+        f = io[v][i] or io[v][string.sub(i,1,1)]
+        if f then f() end
+    end
+    io.open = io.finalize_openers(io.open)
+end
+
+-- restricted
+
+function io.inp.modes.restricted()
+    io.inp.inhibit('^%.[%a]')
+end
+function io.out.modes.restricted()
+    io.out.inhibit('^%.[%a]')
+end
+
+-- paranoid
+
+function io.inp.modes.paranoid()
+    io.inp.inhibit('.*')
+    io.inp.inhibit('%.%.')
+    io.inp.permit('^%./')
+    io.inp.permit('[^/]')
+    input.do_with_path('TEXMF',io.inp.permit)
+end
+function io.out.modes.paranoid()
+    io.out.inhibit('.*')
+    input.do_with_path('TEXMFOUTPUT',io.out.permit)
+end
+
+-- handy
+
+function io.inp.modes.handy()
+    io.inp.inhibit('%.%.')
+    if os.platform == 'linux' then
+        io.inp.inhibit('^/etc')
+    else
+        io.inp.inhibit('/windows/')
+        io.inp.inhibit('/winnt/')
+    end
+end
+function io.out.modes.handy()
+    io.out.inhibit('.*')
+    io.out.permit('%./')
+    io.out.permit('^%./')
+    io.out.permit('[^/]')
+end
+
+--~ io.set_opener_modes('p','p')
+--~ io.set_opener_modes('r','r')
+--~ io.set_opener_modes('h','h')