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annotate src/effectize.sml @ 1183:9d3ccb8b39ac

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author Adam Chlipala <adamc@hcoop.net>
date Tue, 09 Mar 2010 18:28:44 -0500
parents 72670131dace
children b106ca8200b1
rev   line source
adamc@732 1 (* Copyright (c) 2009, Adam Chlipala
adamc@732 2 * All rights reserved.
adamc@732 3 *
adamc@732 4 * Redistribution and use in source and binary forms, with or without
adamc@732 5 * modification, are permitted provided that the following conditions are met:
adamc@732 6 *
adamc@732 7 * - Redistributions of source code must retain the above copyright notice,
adamc@732 8 * this list of conditions and the following disclaimer.
adamc@732 9 * - Redistributions in binary form must reproduce the above copyright notice,
adamc@732 10 * this list of conditions and the following disclaimer in the documentation
adamc@732 11 * and/or other materials provided with the distribution.
adamc@732 12 * - The names of contributors may not be used to endorse or promote products
adamc@732 13 * derived from this software without specific prior written permission.
adamc@732 14 *
adamc@732 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@732 16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@732 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@732 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@732 19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
adamc@732 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@732 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@732 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@732 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@732 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@732 25 * POSSIBILITY OF SUCH DAMAGE.
adamc@732 26 *)
adamc@732 27
adamc@732 28 structure Effective :> EFFECTIZE = struct
adamc@732 29
adamc@732 30 open Core
adamc@732 31
adamc@732 32 structure U = CoreUtil
adamc@732 33
adamc@732 34 structure IM = IntBinaryMap
adamc@732 35 structure SS = BinarySetFn(struct
adamc@732 36 type ord_key = string
adamc@732 37 val compare = String.compare
adamc@732 38 end)
adamc@732 39
adamc@765 40 fun effectful x = Settings.isEffectful x andalso not (Settings.isClientOnly x)
adamc@732 41
adamc@732 42 fun effectize file =
adamc@732 43 let
adamc@782 44 fun expOnload evs e =
adamc@782 45 case e of
adamc@782 46 EFfi f => effectful f
adamc@782 47 | EFfiApp (m, x, _) => effectful (m, x)
adamc@782 48 | ENamed n => IM.inDomain (evs, n)
adamc@1020 49 | EServerCall (n, _, _) => IM.inDomain (evs, n)
adamc@782 50 | _ => false
adamc@782 51
adamc@782 52 fun couldWriteOnload evs = U.Exp.exists {kind = fn _ => false,
adamc@782 53 con = fn _ => false,
adamc@782 54 exp = expOnload evs}
adamc@782 55
adamc@732 56 fun exp evs e =
adamc@732 57 case e of
adamc@765 58 EFfi f => effectful f
adamc@765 59 | EFfiApp (m, x, _) => effectful (m, x)
adamc@732 60 | ENamed n => IM.inDomain (evs, n)
adamc@782 61 | ERecord xets => List.exists (fn ((CName "Onload", _), e, _) => couldWriteOnload evs e
adamc@782 62 | _ => false) xets
adamc@732 63 | _ => false
adamc@732 64
adamc@732 65 fun couldWrite evs = U.Exp.exists {kind = fn _ => false,
adamc@732 66 con = fn _ => false,
adamc@732 67 exp = exp evs}
adamc@732 68
adamc@1104 69 fun exp writers readers e =
adamc@1104 70 case e of
adamc@1104 71 EServerCall (n, _, _) => IM.inDomain (writers, n) andalso IM.inDomain (readers, n)
adamc@1104 72 | _ => false
adamc@1104 73
adamc@1104 74 fun couldWriteWithRpc writers readers = U.Exp.exists {kind = fn _ => false,
adamc@1104 75 con = fn _ => false,
adamc@1104 76 exp = exp writers readers}
adamc@1104 77
adamc@735 78 fun exp evs e =
adamc@735 79 case e of
adamc@735 80 EFfi ("Basis", "getCookie") => true
adamc@735 81 | ENamed n => IM.inDomain (evs, n)
adamc@1020 82 | EServerCall (n, _, _) => IM.inDomain (evs, n)
adamc@735 83 | _ => false
adamc@735 84
adamc@735 85 fun couldReadCookie evs = U.Exp.exists {kind = fn _ => false,
adamc@735 86 con = fn _ => false,
adamc@735 87 exp = exp evs}
adamc@735 88
adamc@1104 89 fun doDecl (d, evs as (writers, readers, pushers)) =
adamc@732 90 case #1 d of
adamc@732 91 DVal (x, n, t, e, s) =>
adamc@735 92 (d, (if couldWrite writers e then
adamc@735 93 IM.insert (writers, n, (#2 d, s))
adamc@735 94 else
adamc@735 95 writers,
adamc@735 96 if couldReadCookie readers e then
adamc@735 97 IM.insert (readers, n, (#2 d, s))
adamc@735 98 else
adamc@1104 99 readers,
adamc@1104 100 if couldWriteWithRpc writers readers e then
adamc@1104 101 IM.insert (pushers, n, (#2 d, s))
adamc@1104 102 else
adamc@1104 103 pushers))
adamc@732 104 | DValRec vis =>
adamc@732 105 let
adamc@732 106 fun oneRound evs =
adamc@1104 107 foldl (fn ((_, n, _, e, s), (changed, (writers, readers, pushers))) =>
adamc@735 108 let
adamc@735 109 val (changed, writers) =
adamc@735 110 if couldWrite writers e andalso not (IM.inDomain (writers, n)) then
adamc@735 111 (true, IM.insert (writers, n, (#2 d, s)))
adamc@735 112 else
adamc@735 113 (changed, writers)
adamc@735 114
adamc@735 115 val (changed, readers) =
adamc@735 116 if couldReadCookie readers e andalso not (IM.inDomain (readers, n)) then
adamc@735 117 (true, IM.insert (readers, n, (#2 d, s)))
adamc@735 118 else
adamc@735 119 (changed, readers)
adamc@1104 120
adamc@1104 121 val (changed, pushers) =
adamc@1104 122 if couldWriteWithRpc writers readers e
adamc@1104 123 andalso not (IM.inDomain (pushers, n)) then
adamc@1104 124 (true, IM.insert (pushers, n, (#2 d, s)))
adamc@1104 125 else
adamc@1104 126 (changed, pushers)
adamc@735 127 in
adamc@1104 128 (changed, (writers, readers, pushers))
adamc@735 129 end) (false, evs) vis
adamc@732 130
adamc@732 131 fun loop evs =
adamc@732 132 let
adamc@732 133 val (b, evs) = oneRound evs
adamc@732 134 in
adamc@732 135 if b then
adamc@732 136 loop evs
adamc@732 137 else
adamc@732 138 evs
adamc@732 139 end
adamc@732 140 in
adamc@1104 141 (d, loop (writers, readers, pushers))
adamc@732 142 end
adamc@1104 143 | DExport (Link, n, _) =>
adamc@735 144 (case IM.find (writers, n) of
adamc@732 145 NONE => ()
adamc@1183 146 | SOME (loc, s) =>
adamc@1183 147 if Settings.isSafeGet s then
adamc@1183 148 ()
adamc@1183 149 else
adamc@1183 150 ErrorMsg.errorAt loc ("A link (" ^ s
adamc@1183 151 ^ ") could cause side effects; try implementing it with a form instead");
adamc@1104 152 ((DExport (Link, n, IM.inDomain (pushers, n)), #2 d), evs))
adamc@1104 153 | DExport (Action _, n, _) =>
adamc@735 154 ((DExport (Action (if IM.inDomain (writers, n) then
adamc@735 155 if IM.inDomain (readers, n) then
adamc@735 156 ReadCookieWrite
adamc@735 157 else
adamc@735 158 ReadWrite
adamc@732 159 else
adamc@1104 160 ReadOnly), n, IM.inDomain (pushers, n)), #2 d),
adamc@732 161 evs)
adamc@1104 162 | DExport (Rpc _, n, _) =>
adamc@735 163 ((DExport (Rpc (if IM.inDomain (writers, n) then
adamc@735 164 if IM.inDomain (readers, n) then
adamc@735 165 ReadCookieWrite
adamc@735 166 else
adamc@735 167 ReadWrite
adamc@732 168 else
adamc@1104 169 ReadOnly), n, IM.inDomain (pushers, n)), #2 d),
adamc@732 170 evs)
adamc@732 171 | _ => (d, evs)
adamc@732 172
adamc@1104 173 val (file, _) = ListUtil.foldlMap doDecl (IM.empty, IM.empty, IM.empty) file
adamc@732 174 in
adamc@732 175 file
adamc@732 176 end
adamc@732 177
adamc@732 178 end