From c9a2d4cca8a1a9d77684caa680ab059ad94da2b0 Mon Sep 17 00:00:00 2001
From: baldurk <baldurk@baldurk.org>
Date: Tue, 13 Feb 2018 19:33:37 +0000
Subject: [PATCH] Fetch declared #version for each shader (will be needed on
 GLES)

---
 renderdoc/driver/gl/gl_driver.h               |  3 +-
 renderdoc/driver/gl/gl_shader_refl.cpp        | 20 +++++
 renderdoc/driver/gl/gl_shader_refl.h          |  1 +
 .../driver/gl/wrappers/gl_shader_funcs.cpp    | 81 +++++++++++++++++++
 4 files changed, 104 insertions(+), 1 deletion(-)

diff --git a/renderdoc/driver/gl/gl_driver.h b/renderdoc/driver/gl/gl_driver.h
index 11a68391b..2bc7fe10c 100644
--- a/renderdoc/driver/gl/gl_driver.h
+++ b/renderdoc/driver/gl/gl_driver.h
@@ -288,7 +288,7 @@ private:
 
   struct ShaderData
   {
-    ShaderData() : type(eGL_NONE), prog(0) {}
+    ShaderData() : type(eGL_NONE), prog(0), version(0) {}
     GLenum type;
     vector<string> sources;
     vector<string> includepaths;
@@ -296,6 +296,7 @@ private:
     std::string disassembly;
     ShaderReflection reflection;
     GLuint prog;
+    int version;
 
     void Compile(WrappedOpenGL &gl, ResourceId id, GLuint realShader);
   };
diff --git a/renderdoc/driver/gl/gl_shader_refl.cpp b/renderdoc/driver/gl/gl_shader_refl.cpp
index a04c59a42..d822de364 100644
--- a/renderdoc/driver/gl/gl_shader_refl.cpp
+++ b/renderdoc/driver/gl/gl_shader_refl.cpp
@@ -835,6 +835,26 @@ void ReconstructVarTree(const GLHookSet &gl, GLenum query, GLuint sepProg, GLuin
   }
 }
 
+int ParseVersionStatement(const char *version)
+{
+  if(strncmp(version, "#version", 8))
+    return 0;
+
+  version += 8;
+  while(isspace(*version))
+    version++;
+
+  int ret = 0;
+  while(*version >= '0' && *version <= '9')
+  {
+    ret *= 10;
+    ret += int(*version) - int('0');
+    version++;
+  }
+
+  return ret;
+}
+
 void MakeShaderReflection(const GLHookSet &gl, GLenum shadType, GLuint sepProg,
                           ShaderReflection &refl, bool pointSizeUsed, bool clipDistanceUsed)
 {
diff --git a/renderdoc/driver/gl/gl_shader_refl.h b/renderdoc/driver/gl/gl_shader_refl.h
index 55b40a0ba..b352d41ac 100644
--- a/renderdoc/driver/gl/gl_shader_refl.h
+++ b/renderdoc/driver/gl/gl_shader_refl.h
@@ -27,6 +27,7 @@
 
 class WrappedOpenGL;
 
+int ParseVersionStatement(const char *version);
 void MakeShaderReflection(const GLHookSet &gl, GLenum shadType, GLuint sepProg,
                           ShaderReflection &refl, bool pointSizeUsed, bool clipDistanceUsed);
 GLuint MakeSeparableShaderProgram(WrappedOpenGL &gl, GLenum type, std::vector<std::string> sources,
diff --git a/renderdoc/driver/gl/wrappers/gl_shader_funcs.cpp b/renderdoc/driver/gl/wrappers/gl_shader_funcs.cpp
index 9841dea8d..2227be1df 100644
--- a/renderdoc/driver/gl/wrappers/gl_shader_funcs.cpp
+++ b/renderdoc/driver/gl/wrappers/gl_shader_funcs.cpp
@@ -77,6 +77,87 @@ void WrappedOpenGL::ShaderData::Compile(WrappedOpenGL &gl, ResourceId id, GLuint
     concatenated += sources[i];
   }
 
+  size_t offs = concatenated.find("#version");
+
+  if(offs == std::string::npos)
+  {
+    // if there's no #version it's assumed to be 100 which we set below
+    version = 0;
+  }
+  else
+  {
+    // see if we find a second result after the first
+    size_t offs2 = concatenated.find("#version", offs + 1);
+
+    if(offs2 == std::string::npos)
+    {
+      version = ParseVersionStatement(concatenated.c_str() + offs);
+    }
+    else
+    {
+      // slow path, multiple #version matches so the first one might be in a comment. We need to
+      // search from the start, past comments and whitespace, to find the first real #version.
+      const char *search = concatenated.c_str();
+      const char *end = search + concatenated.size();
+
+      while(search < end)
+      {
+        // skip whitespace
+        if(isspace(*search))
+        {
+          search++;
+          continue;
+        }
+
+        // skip single-line C++ style comments
+        if(search + 1 < end && search[0] == '/' && search[1] == '/')
+        {
+          // continue until the next newline
+          while(search < end && search[0] != '\r' && search[0] != '\n')
+            search++;
+
+          // continue, the whitespace skip above will skip the newline
+          continue;
+        }
+
+        // skip multi-line C style comments
+        if(search + 1 < end && search[0] == '/' && search[1] == '*')
+        {
+          // continue until the ending marker
+          while(search + 1 < end && (search[0] != '*' || search[1] != '/'))
+            search++;
+
+          // skip the end marker
+          search += 2;
+
+          // continue, the whitespace skip above will skip the newline
+          continue;
+        }
+
+        // missing #version is valid, so just exit
+        if(search + sizeof("#version") > end)
+        {
+          RDCERR("Bad shader - reached end of text after skipping all comments and whitespace");
+          break;
+        }
+
+        std::string versionText(search, search + sizeof("#version") - 1);
+
+        // if we found the version, parse it
+        if(versionText == "#version")
+          version = ParseVersionStatement(search);
+
+        // otherwise break - a missing #version is valid, and a legal #version cannot occur anywhere
+        // after this point.
+        break;
+      }
+    }
+  }
+
+  // default to version 100
+  if(version == 0)
+    version = 100;
+
   reflection.encoding = ShaderEncoding::GLSL;
   reflection.rawBytes.assign((byte *)concatenated.c_str(), concatenated.size());