translate.h

   1 // -*- C++ -*-
   2 // Copyright (C) 2005, 2009 Red Hat Inc.
   3 //
   4 // This file is part of systemtap, and is free software.  You can
   5 // redistribute it and/or modify it under the terms of the GNU General
   6 // Public License (GPL); either version 2, or (at your option) any
   7 // later version.
   8
   9 #ifndef TRANSLATE_H
  10 #define TRANSLATE_H
  11
  12 #include "staptree.h"
  13 #include "parse.h"
  14 #include <iostream>
  15 #include <fstream>
  16
  17
  18 // ------------------------------------------------------------------------
  19
  20 // Output context for systemtap translation, intended to allow
  21 // pretty-printing.
  22 class translator_output
  23 {
  24   char *buf;
  25   std::ofstream* o2;
  26   std::ostream& o;
  27   unsigned tablevel;
  28
  29 public:
  30   translator_output (std::ostream& file);
  31   translator_output (const std::string& filename, size_t bufsize = 8192);
  32   ~translator_output ();
  33
  34   std::ostream& newline (int indent = 0);
  35   void indent (int indent = 0);
  36   void assert_0_indent () { o << std::flush; assert (tablevel == 0); }
  37   std::ostream& line();
  38
  39   std::ostream::pos_type tellp() { return o.tellp(); }
  40   std::ostream& seekp(std::ostream::pos_type p) { return o.seekp(p); }
  41 };
  42
  43
  44 // An unparser instance is in charge of emitting code for generic
  45 // probe bodies, functions, globals.
  46 struct unparser
  47 {
  48   virtual ~unparser () {}
  49
  50   virtual void emit_common_header () = 0;
  51   // #include<...>
  52   //
  53   // #define MAXNESTING nnn
  54   // #define MAXCONCURRENCY mmm
  55   // #define MAXSTRINGLEN ooo
  56   //
  57   // enum session_state_t {
  58   //   starting, begin, running, suspended, errored, ending, ended
  59   // };
  60   // static atomic_t session_state;
  61   //
  62   // struct context {
  63   //   unsigned errorcount;
  64   //   unsigned busy;
  65   //   ...
  66   // } context [MAXCONCURRENCY];
  67
  68   // struct {
  69   virtual void emit_global (vardecl* v) = 0;
  70   // TYPE s_NAME;  // NAME is prefixed with "s_" to avoid kernel id collisions
  71   // rwlock_t s_NAME_lock;
  72   // } global = {
  73   virtual void emit_global_init (vardecl* v) = 0;
  74   // };
  75
  76   virtual void emit_global_param (vardecl* v) = 0;
  77   // module_param_... -- at end of file
  78
  79   virtual void emit_functionsig (functiondecl* v) = 0;
  80   // static void function_NAME (context* c);
  81
  82   virtual void emit_module_init () = 0;
  83   virtual void emit_module_refresh () = 0;
  84   virtual void emit_module_exit () = 0;
  85   // startup, probe refresh/activation, shutdown
  86
  87   virtual void emit_function (functiondecl* v) = 0;
  88   // void function_NAME (struct context* c) {
  89   //   ....
  90   // }
  91
  92   virtual void emit_probe (derived_probe* v) = 0;
  93   // void probe_NUMBER (struct context* c) {
  94   //   ... lifecycle
  95   //   ....
  96   // }
  97   // ... then call over to the derived_probe's emit_probe_entries() fn
  98 };
  99
 100
 101 // Preparation done before checking the script cache, especially
 102 // anything that might affect the hashed name.
 103 int prepare_translate_pass (systemtap_session& s);
 104
 105 int translate_pass (systemtap_session& s);
 106
 107
 108 #endif // TRANSLATE_H
 109
 110 /* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */