Update Sphinx documentation

These changes allow the documentation to be hosted on readthedocs.io.

Also, update a code sample to avoid a nullptr access

Author: chesik-amd

docs/source/_static/theme_overrides.css

@@ -1,8 +1,5 @@
-/* This override allows text in table cells to wrap.
-   Without this override, the descritpions in the
-   command line options tables  are very long and
-   the table is displayed with a horizontal scroll
-   bar */
+/* This override allows text in table cells to wrap.*/
+
 @media screen and (min-width: 767px) {
 
    .wy-table-responsive table td {
@@ -17,5 +14,5 @@
 }
 
 table.docutils div.line-block {
-    margin-left: 0;
+    margin-left: 0 !important;
 }

docs/source/conf.py

@@ -115,11 +115,12 @@
 # so a file named "default.css" will overwrite the builtin "default.css".
 html_static_path = ['_static']
 
-html_context = {
-    'css_files': [
-        '_static/theme_overrides.css',  # override wide tables in RTD theme
-    ],
-}
+# If a function setup(app) exists, Sphinx will call this function as a normal
+# extension during application startup. This method of using the overrides css
+# file works better with read the docs (more so than specifying it via the
+# html_context tag)
+def setup(app):
+    app.add_stylesheet('theme_overrides.css')
 
 # Custom sidebar templates, must be a dictionary that maps document names
 # to template names.

docs/source/usage.rst

@@ -69,16 +69,23 @@ initialize the DirectX 12 version of GPA:
 
     GPAApiManager* GPAApiManager::m_pGpaApiManager = nullptr;
 
-    GPAFunctionTable* pGpaFunctionTable;
+    GPAFunctionTable* pGpaFunctionTable = nullptr;
 
     bool InitializeGPA()
     {
+        bool retVal = false;
+
         if (GPA_STATUS_OK == GPAApiManager::Instance()->LoadApi(GPA_API_DIRECTX_12))
         {
             pGpaFunctionTable = GPAApiManager::Instance()->GetFunctionTable(GPA_API_DIRECTX_12);
+
+            if (nullptr != pGpaFunctionTable)
+            {
+                retVal = GPA_STATUS_OK == pGpaFunctionTable->GPA_Initialize(GPA_INITIALIZE_DEFAULT_BIT);
+            }
         }
 
-        return GPA_STATUS_OK == pGpaFunctionTable->GPA_Initialize(GPA_INITIALIZE_DEFAULT_BIT);
+        return retVal;
     }
 
 Registering a Logging Callback
@@ -170,7 +177,7 @@ required type which should be passed to GPA_OpenContext:
 Querying a Context and Counters
 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
 
-After creating a Context, you can use the returned GPA_ContextId to query
+After creating a context, you can use the returned GPA_ContextId to query
 information about the context and the performance counters exposed by the
 context.