gen_cxx.ml

   1 (* C++ code generation *)
   2
   3 open ExtList
   4 open ExtString
   5 open Operators
   6 open Printf
   7 open Apply
   8
   9 open Stmt
  10 open Gen
  11 open Sql
  12
  13 module Values = struct
  14
  15 let names = List.map fst
  16 let join = String.concat ", "
  17 let inline = join & names
  18 let to_string = join & (List.map (fun (n,t) -> t ^ " " ^ n))
  19
  20 end
  21
  22 let rec freshname name scope =
  23   match List.find_all ((=) name) scope with
  24   | [] -> name
  25   | _ -> freshname (name ^ "_") scope
  26
  27 let quote = String.replace_chars (function '\n' -> "\\n\\\n" | '\r' -> "" | '"' -> "\\\"" | c -> String.make 1 c)
  28 let quote s = "\"" ^ quote s ^ "\""
  29
  30 let quote_comment_inline = String.replace_chars (function '\n' -> "\n// " | c -> String.make 1 c)
  31 let comment () fmt = Printf.kprintf (indent_endline & quote_comment_inline & (^) "// ") fmt
  32 let empty_line () = print_newline ()
  33 let open_curly () = output "{"; inc_indent ()
  34 let close_curly fmt = dec_indent (); indent "}"; print fmt
  35 let start_struct name =
  36    output "struct %s" name;
  37    open_curly ()
  38 let end_struct name =
  39    close_curly "; // struct %s" name;
  40    empty_line ()
  41 let out_public () = dec_indent(); output "public:"; inc_indent()
  42 let out_private () = dec_indent(); output "private:"; inc_indent()
  43
  44 module L = struct
  45   let as_api_type = Type.to_string
  46   let as_lang_type t = "typename Traits::" ^ (as_api_type t)
  47 end
  48
  49 module T = Translate(L)
  50
  51 open L
  52 open T
  53
  54 let column_action action attr index =
  55   let typ = as_api_type attr.RA.domain in
  56   let name = name_of attr index in
  57   output "Traits::%s_column_%s(row, %u, %s);" action typ index name
  58
  59 let func head name args ?tail k =
  60   let tail = match tail with
  61   | Some s -> " " ^ s
  62   | None -> ""
  63   in
  64   let head = match head with "" -> "" | s -> s ^ " " in
  65   output "%s%s(%s)%s" head name (Values.to_string args) tail;
  66   open_curly ();
  67   k ();
  68   close_curly ""
  69
  70 let set_param arg index param =
  71   let (id,t) = param in
  72   output "Traits::set_param(%s, %s, %u);"
  73 (*     (param_type_to_string t) *)
  74     arg
  75     (param_name_to_string id index)
  76     index
  77
  78 let output_value_defs vals =
  79   vals >> List.iter (fun (name,t) -> output "%s %s;" t name)
  80
  81 let output_schema_binder index schema =
  82   out_private ();
  83   let name = "output" in
  84   output "template <class T>";
  85   start_struct name;
  86
  87   let vals = schema_to_values schema in
  88   output_value_defs vals;
  89   empty_line ();
  90
  91   output "enum { count = %u };" (List.length schema);
  92   empty_line ();
  93
  94   let mthd action active =
  95     func "void" action
  96       (["row","typename Traits::row"] @ (if active then ["result","T"] else []))
  97       (fun () ->
  98         List.iteri (fun index attr -> column_action action attr index) schema;
  99         if active then output "result(%s);" (Values.inline vals)
 100       )
 101   in
 102
 103   mthd "get" true;
 104   mthd "bind" false;
 105
 106   end_struct name;
 107   name
 108
 109 let output_schema_binder index schema =
 110   match schema with
 111   | [] -> None
 112   | _ -> Some (output_schema_binder index schema)
 113
 114 let make_const_values = List.map (fun (name,t) -> name, sprintf "%s const&" t)
 115
 116 (*
 117 let output_schema_data index schema =
 118   out_public ();
 119   let name = "data" in
 120   start_struct name;
 121   schema >> schema_to_values >> output_value_defs;
 122   end_struct name
 123 *)
 124
 125 let value_inits vals =
 126   match vals with
 127   | [] -> ""
 128   | _ -> sprintf ": %s" (String.concat "," (List.map (fun (name,_) -> sprintf "%s(%s)" name name) vals))
 129
 130 let struct_params name values k =
 131   start_struct name;
 132   output_value_defs values;
 133   empty_line ();
 134   k ();
 135   end_struct name
 136
 137 let struct_ctor name values k =
 138   struct_params name values (fun () ->
 139     func "" name values ~tail:(value_inits values) Apply.id;
 140     empty_line ();
 141     k ())
 142
 143 let output_params_binder index params =
 144   out_private ();
 145   let name = "params" in
 146   let values = params_to_values params in
 147   struct_ctor name (make_const_values values) (fun () ->
 148     comment () "binding slots in a query (one param may be bound several times)";
 149     output "enum { count = %u };" (List.length params);
 150     empty_line ();
 151     let arg = freshname "target" (name :: Values.names values) in
 152     output "template <class T>";
 153     func "void" "set_params" [arg,"T&"] (fun () -> List.iteri (set_param arg) params);
 154     empty_line ()
 155   );
 156   name
 157
 158 let output_params_binder index params =
 159   match params with
 160   | [] -> "typename Traits::no_params"
 161   | _ -> output_params_binder index params
 162
 163 type t = unit
 164
 165 let start () = ()
 166
 167 let make_stmt index stmt =
 168    let name = choose_name stmt.props stmt.kind index in
 169    let sql = quote (get_sql stmt) in
 170    struct_params name ["stmt","typename Traits::statement"] (fun () ->
 171     func "" name ["db","typename Traits::connection"] ~tail:(sprintf ": stmt(db,SQLGG_STR(%s))" sql) Apply.id;
 172    let schema_binder_name = output_schema_binder index stmt.schema in
 173    let params_binder_name = output_params_binder index stmt.params in
 174 (*    if (Option.is_some schema_binder_name) then output_schema_data index stmt.schema; *)
 175    out_public ();
 176    if (Option.is_some schema_binder_name) then output "template<class T>";
 177    let values = params_to_values stmt.params in
 178    let result = match schema_binder_name with None -> [] | Some _ -> ["result","T"] in
 179    let all_params = (make_const_values values) @ result in
 180    let inline_params = Values.inline (make_const_values values) in
 181    func "bool" "operator()" all_params (fun () ->
 182     begin match schema_binder_name with
 183     | None -> output "return stmt.execute(%s(%s));" params_binder_name inline_params
 184     | Some schema_name -> output "return stmt.select(result,%s<T>(),%s(%s));"
 185           schema_name params_binder_name inline_params
 186     end);
 187    );
 188    name
 189
 190 let make_all name names =
 191   List.iter (fun name -> output "%s %s;" name name) names;
 192   empty_line ();
 193   let tail = match names with
 194   | [] -> ""
 195   | _ -> ": " ^ (String.concat ", " (List.map (fun name -> sprintf "%s(db)" name) names))
 196   in
 197   func "" name ["db","typename Traits::connection"] ~tail Apply.id
 198
 199 let generate () name stmts =
 200   output "#pragma once";
 201   empty_line ();
 202   output "template <class Traits>";
 203   start_struct name;
 204   let stmts = List.of_enum stmts in
 205   let names = List.mapi make_stmt stmts in
 206   make_all name names;
 207   end_struct name
 208