Set up NaClChromeMainArgs number_of_cores member so apps can size threadpools appropriately

chrome/test/nacl/nacl_browsertest.cc

Index: chrome/test/nacl/nacl_browsertest.cc
diff --git a/chrome/test/nacl/nacl_browsertest.cc b/chrome/test/nacl/nacl_browsertest.cc
index 9336311d21664d7352a6c4da9046a2b8fabcf4c8..3e34870b67eb175679d729c8fafb2cca824aab99 100644
--- a/chrome/test/nacl/nacl_browsertest.cc
+++ b/chrome/test/nacl/nacl_browsertest.cc
@@ -2,6 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <stdio.h>
+#if defined(OS_POSIX)
+#include <unistd.h>
+#elif defined(OS_WIN)
+#include <windows.h>
+#endif
+
 #include "chrome/test/nacl/nacl_browsertest_util.h"
 
 namespace {
@@ -18,6 +25,7 @@ namespace {
 #define MAYBE_CrossOriginFail DISABLED_CrossOriginFail
 #define MAYBE_SameOriginCookie DISABLED_SameOriginCookie
 #define MAYBE_CORSNoCookie DISABLED_CORSNoCookie
+#define MAYBE_SysconfNprocessorsOnln DISABLED_SysconfNprocessorsOnln
 #else
 #define MAYBE_SimpleLoad SimpleLoad
 #define MAYBE_ExitStatus0 ExitStatus0
@@ -29,6 +37,7 @@ namespace {
 #define MAYBE_CrossOriginFail CrossOriginFail
 #define MAYBE_SameOriginCookie SameOriginCookie
 #define MAYBE_CORSNoCookie CORSNoCookie
+#define MAYBE_SysconfNprocessorsOnln SysconfNprocessorsOnln
 #endif
 
 NACL_BROWSER_TEST_F(NaClBrowserTest, MAYBE_SimpleLoad, {
@@ -58,6 +67,36 @@ NACL_BROWSER_TEST_F(NaClBrowserTest, MAYBE_ProgressEvents, {
   RunNaClIntegrationTest(FILE_PATH_LITERAL("ppapi_progress_events.html"));
 })
 
+// Visual Studio does not like preprocessor conditionals inside the
+// argument of a macro, so we put the conditionals on a helper
+// function.  We are already in an anonymous namespace, so the name of
+// the helper is not visible in external scope.
+//
+// The string buffer is sufficient sized: 2**64 < 8**22 < 10**22.
+#if defined(OS_POSIX)
+base::FilePath::StringType NumberOfCoresAsFilePathString() {
+  char string_rep[23];
+  snprintf(string_rep, sizeof string_rep, "%ld", sysconf(_SC_NPROCESSORS_ONLN));
+  return string_rep;
+}
+#elif defined(OS_WIN)
+base::FilePath::StringType NumberOfCoresAsFilePathString() {
+  wchar_t string_rep[23];
+  SYSTEM_INFO system_info;
+  GetSystemInfo(&system_info);
+  _snwprintf_s(string_rep, sizeof string_rep, _TRUNCATE, L"%u",
+               system_info.dwNumberOfProcessors);
+  return string_rep;
+}
+#endif
+
+NACL_BROWSER_TEST_F(NaClBrowserTest, MAYBE_SysconfNprocessorsOnln, {
+    base::FilePath::StringType path =
+        FILE_PATH_LITERAL("sysconf_nprocessors_onln_test.html?cpu_count=");
+    path = path + NumberOfCoresAsFilePathString();
+    RunNaClIntegrationTest(path);
+})
+
 IN_PROC_BROWSER_TEST_F(NaClBrowserTestStatic, MAYBE_CrossOriginCORS) {
   RunLoadTest(FILE_PATH_LITERAL("cross_origin/cors.html"));
 }