summaryrefslogtreecommitdiff
path: root/src/lru_cache.sml
blob: b66becb7c5170d6f2905f97c52792e8dc0bb6020 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
structure LruCache : sig
    val cache : Cache.cache
end = struct


(* Mono *)

open Mono

val dummyLoc = ErrorMsg.dummySpan
val stringTyp = (TFfi ("Basis", "string"), dummyLoc)
val optionStringTyp = (TOption stringTyp, dummyLoc)
fun withTyp typ = map (fn exp => (exp, typ))

fun ffiAppCache' (func, index, argTyps) =
    EFfiApp ("Sqlcache", func ^ Int.toString index, argTyps)

fun check (index, keys) =
    ffiAppCache' ("check", index, withTyp stringTyp keys)

fun store (index, keys, value) =
    ffiAppCache' ("store", index, (value, stringTyp) :: withTyp stringTyp keys)

fun flush (index, keys) =
    ffiAppCache' ("flush", index, withTyp optionStringTyp keys)

fun lock (index, write) =
    ffiAppCache' ((if write then "w" else "r") ^ "lock", index, [])


(* Cjr *)

open Print
open Print.PD

fun setupQuery {index, params} =
    let

        val i = Int.toString index

        fun paramRepeat itemi sep =
            let
                fun f n =
                    if n < 0 then ""
                    else if n = 0 then itemi (Int.toString 0)
                    else f (n-1) ^ sep ^ itemi (Int.toString n)
            in
                f (params - 1)
            end

        fun paramRepeatRev itemi sep =
            let
                fun f n =
                    if n < 0 then ""
                    else if n = 0 then itemi (Int.toString 0)
                    else itemi (Int.toString n) ^ sep ^ f (n-1)
            in
                f (params - 1)
            end

        fun paramRepeatInit itemi sep =
            if params = 0 then "" else sep ^ paramRepeat itemi sep

        val typedArgs = paramRepeatInit (fn p => "uw_Basis_string p" ^ p) ", "

        val revArgs = paramRepeatRev (fn p => "p" ^ p) ", "

    in
        Print.box
            [string ("static uw_Sqlcache_Cache cacheStruct" ^ i ^ " = {"),
             newline,
             string "  .lock = PTHREAD_RWLOCK_INITIALIZER,",
             newline,
             string "  .table = NULL,",
             newline,
             string ("  .numKeys = " ^ Int.toString params ^ ","),
             newline,
             string "  .timeInvalid = 0,",
             newline,
             string "  .timeNow = 0};",
             newline,
             string ("static uw_Sqlcache_Cache *cache" ^ i ^ " = &cacheStruct" ^ i ^ ";"),
             newline,
             newline,

             string ("static uw_Basis_string uw_Sqlcache_check" ^ i),
             string ("(uw_context ctx" ^ typedArgs ^ ") {"),
             newline,
             string ("  char *ks[] = {" ^ revArgs ^ "};"),
             newline,
             string ("  uw_Sqlcache_Value *v = uw_Sqlcache_check(ctx, cache" ^ i ^ ", ks);"),
             newline,
             (* If the output is null, it means we had too much recursion, so it's a miss. *)
             string "  if (v && v->output != NULL) {",
             newline,
             string ("    puts(\"SQLCACHE: hit " ^ i ^ ".\");"),
             newline,
             string "    uw_write(ctx, v->output);",
             newline,
             string "    return v->result;",
             newline,
             string "  } else {",
             newline,
             string ("    puts(\"SQLCACHE: miss " ^ i ^ ".\");"),
             newline,
             string "    uw_recordingStart(ctx);",
             newline,
             string "    return NULL;",
             newline,
             string "  }",
             newline,
             string "}",
             newline,
             newline,

             string ("static uw_unit uw_Sqlcache_store" ^ i),
             string ("(uw_context ctx, uw_Basis_string s" ^ typedArgs ^ ") {"),
             newline,
             string ("  char *ks[] = {" ^ revArgs ^ "};"),
             newline,
             string ("  uw_Sqlcache_Value *v = malloc(sizeof(uw_Sqlcache_Value));"),
             newline,
             string "  v->result = strdup(s);",
             newline,
             string "  v->output = uw_recordingRead(ctx);",
             newline,
             string ("  puts(\"SQLCACHE: stored " ^ i ^ ".\");"),
             newline,
             string ("  uw_Sqlcache_store(ctx, cache" ^ i ^ ", ks, v);"),
             newline,
             string "  return uw_unit_v;",
             newline,
             string "}",
             newline,
             newline,

             string ("static uw_unit uw_Sqlcache_flush" ^ i),
             string ("(uw_context ctx" ^ typedArgs ^ ") {"),
             newline,
             string ("  char *ks[] = {" ^ revArgs ^ "};"),
             newline,
             string ("  uw_Sqlcache_flush(ctx, cache" ^ i ^ ", ks);"),
             newline,
             string "  return uw_unit_v;",
             newline,
             string "}",
             newline,
             newline]
    end

val setupGlobal = string "/* No global setup for LRU cache. */"


(* Bundled up. *)

(* For now, use the toy implementation if there are no arguments. *)
fun toyIfNoKeys numKeys implLru implToy args =
    if numKeys args = 0
    then implToy args
    else implLru args

val cache =
    (* let *)
    (*     val {check = toyCheck, *)
    (*          store = toyStore, *)
    (*          flush = toyFlush, *)
    (*          setupQuery = toySetupQuery, *)
    (*          ...} = ToyCache.cache *)
    (* in *)
        (* {check = toyIfNoKeys (length o #2) check toyCheck, *)
        (*  store = toyIfNoKeys (length o #2) store toyStore, *)
        (*  flush = toyIfNoKeys (length o #2) flush toyFlush, *)
    {check = check, store = store, flush = flush, lock = lock,
     setupQuery = setupQuery, setupGlobal = setupGlobal}
    (* end *)

end