gfx/thebes/gfxEnv.h

   1 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef GFX_ENV_H
   7 #define GFX_ENV_H
   8
   9 #include "mozilla/Attributes.h"
  10 #include "nsDebug.h"
  11 #include "prenv.h"
  12
  13 #include <sstream>
  14 #include <string_view>
  15
  16 // To register the check for an environment variable existence (and not empty),
  17 // add a line in this file using the DECL_GFX_ENV macro.
  18 //
  19 // For example this line in the .h:
  20 //   DECL_GFX_ENV(MOZ_GL_SPEW);
  21
  22 // means that you can call e.g.
  23 //   if (gfxEnv::MOZ_GL_SPEW()) { ... }
  24 //   if (gfxEnv::MOZ_GL_SPEW().as_str == "2") { ... }
  25 // and that the value will be checked only once, first time we call it, then
  26 // cached.
  27
  28 struct EnvVal {
  29   std::string_view as_str;
  30
  31   static auto From(const char* const raw) {
  32     auto ret = EnvVal{};
  33
  34     ret.as_str = std::string_view{};
  35     // Empty string counts as missing.
  36     if (raw) {
  37       ret.as_str = raw;
  38     }
  39
  40     return ret;
  41   }
  42
  43   MOZ_IMPLICIT operator bool() const {
  44     return !as_str.empty();  // Warning, this means ENV=0" -> true!
  45   }
  46 };
  47
  48 class gfxEnv final {
  49  public:
  50   gfxEnv() = delete;
  51
  52   static EnvVal Uncached(const char* name) {
  53     const auto raw = PR_GetEnv(name);
  54     const auto ret = EnvVal::From(raw);
  55     if (ret && ret.as_str == "0") {
  56       auto msg = std::stringstream{};
  57       msg << name << "=" << ret.as_str << " -> true!";
  58       NS_WARNING(msg.str().c_str());
  59     }
  60     return ret;
  61   }
  62
  63 #define DECL_GFX_ENV(Name)                      \
  64   static const EnvVal& Name() {                 \
  65     static const auto cached = Uncached(#Name); \
  66     return cached;                              \
  67   }
  68
  69   // This is where DECL_GFX_ENV for each of the environment variables should go.
  70   // We will keep these in an alphabetical order by the environment variable,
  71   // to make it easier to see if a method accessing an entry already exists.
  72   // Just insert yours in the list.
  73
  74   // OpenGL shader debugging in OGLShaderProgram, in DEBUG only
  75   DECL_GFX_ENV(MOZ_DEBUG_SHADERS)
  76
  77   // Disabling the crash guard in DriverCrashGuard
  78   DECL_GFX_ENV(MOZ_DISABLE_CRASH_GUARD)
  79   DECL_GFX_ENV(MOZ_FORCE_CRASH_GUARD_NIGHTLY)
  80
  81   // We force present to work around some Windows bugs - disable that if this
  82   // environment variable is set.
  83   DECL_GFX_ENV(MOZ_DISABLE_FORCE_PRESENT)
  84
  85   // Together with paint dumping, only when MOZ_DUMP_PAINTING is defined.
  86   // Dumping compositor textures is broken pretty badly. For example,
  87   // on Linux it crashes TextureHost::GetAsSurface() returns null.
  88   // Expect to have to fix things like this if you turn it on.
  89   // Meanwhile, content-side texture dumping
  90   // (conditioned on DebugDumpPainting()) is a good replacement.
  91   DECL_GFX_ENV(MOZ_DUMP_COMPOSITOR_TEXTURES)
  92
  93   // Dump GLBlitHelper shader source text.
  94   DECL_GFX_ENV(MOZ_DUMP_GLBLITHELPER)
  95
  96   // Paint dumping, only when MOZ_DUMP_PAINTING is defined.
  97   DECL_GFX_ENV(MOZ_DUMP_PAINT)
  98   DECL_GFX_ENV(MOZ_DUMP_PAINT_ITEMS)
  99   DECL_GFX_ENV(MOZ_DUMP_PAINT_TO_FILE)
 100
 101   // Force gfxDevCrash to use MOZ_CRASH in Beta and Release
 102   DECL_GFX_ENV(MOZ_GFX_CRASH_MOZ_CRASH)
 103   // Force gfxDevCrash to use telemetry in Nightly and Aurora
 104   DECL_GFX_ENV(MOZ_GFX_CRASH_TELEMETRY)
 105
 106   // Debugging in GLContext
 107   DECL_GFX_ENV(MOZ_GL_DEBUG)
 108   DECL_GFX_ENV(MOZ_GL_DEBUG_VERBOSE)
 109   DECL_GFX_ENV(MOZ_GL_DEBUG_ABORT_ON_ERROR)
 110   DECL_GFX_ENV(MOZ_GL_RELEASE_ASSERT_CONTEXT_OWNERSHIP)
 111   DECL_GFX_ENV(MOZ_EGL_RELEASE_ASSERT_CONTEXT_OWNERSHIP)
 112
 113   // Count GL extensions
 114   DECL_GFX_ENV(MOZ_GL_DUMP_EXTS)
 115
 116   // Very noisy GLContext and GLContextProviderEGL
 117   DECL_GFX_ENV(MOZ_GL_SPEW)
 118
 119   // Do extra work before and after each GLX call in GLContextProviderGLX
 120   DECL_GFX_ENV(MOZ_GLX_DEBUG)
 121
 122   // GL compositing on Windows
 123   DECL_GFX_ENV(MOZ_LAYERS_PREFER_EGL)
 124
 125   // Offscreen GL context for main layer manager
 126   DECL_GFX_ENV(MOZ_LAYERS_PREFER_OFFSCREEN)
 127
 128   // WebGL workarounds
 129   DECL_GFX_ENV(MOZ_WEBGL_WORKAROUND_FIRST_AFFECTS_INSTANCE_ID)
 130
 131   // WARNING:
 132   // For readability reasons, please make sure that you've added your new envvar
 133   // to the list above in alphabetical order.
 134   // Please do not just append it to the end of the list!
 135
 136 #undef DECL_GFX_ENV
 137 };
 138
 139 #endif /* GFX_ENV_H */