Add InspectModule() that returns a populated ModuleInspectionResult struct

chrome/browser/conflicts/module_info_util_win.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/conflicts/module_info_util_win.h"
 
 #include <windows.h>
 
 #include <tlhelp32.h>
 #include <wincrypt.h>
 #include <wintrust.h>
 
 // This must be after wincrypt and wintrust.
 #include <mscat.h>
 
+#include <limits>
 #include <memory>
-#include <vector>
+#include <string>
 
+#include "base/environment.h"
+#include "base/i18n/case_conversion.h"
 #include "base/scoped_generic.h"
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversions.h"
 #include "base/win/scoped_handle.h"
 
 namespace {
 
 // Helper for scoped tracking an HCERTSTORE.
 struct ScopedHCERTSTORETraits {
   static HCERTSTORE InvalidValue() { return nullptr; }
   static void Free(HCERTSTORE store) { ::CertCloseStore(store, 0); }
 };
 using ScopedHCERTSTORE =
@@ skipping 201 matching lines @@
     return;
 
   base::string16 subject = GetSubjectNameInFile(filename);
   if (subject.empty())
     return;
 
   certificate_info->type = CertificateType::CERTIFICATE_IN_FILE;
   certificate_info->path = filename;
   certificate_info->subject = subject;
 }
+
+StringMapping GetEnvironmentVariablesMapping(
+    const std::vector<base::string16>& environment_variables) {
+  std::unique_ptr<base::Environment> environment(base::Environment::Create());
+
+  StringMapping string_mapping;
+  for (const base::string16& variable : environment_variables) {
+    std::string value;
+    if (environment->GetVar(base::UTF16ToASCII(variable).c_str(), &value)) {
+      string_mapping.push_back(
+          std::make_pair(base::i18n::ToLower(base::UTF8ToUTF16(value)),
+                         L"%" + base::i18n::ToLower(variable) + L"%"));
+    }
+  }
+
+  return string_mapping;
+}
+
+void CollapseMatchingPrefixInString(const StringMapping& prefix_mapping,
+                                    base::string16* string) {
+  size_t min_length = std::numeric_limits<size_t>::max();
+  const base::string16& lower_string = base::i18n::ToLower(*string);
+  for (const auto& mapping : prefix_mapping) {
+    const base::string16& prefix = base::i18n::ToLower(mapping.first);

[chrisha, 2017/02/28 18:51:28]

Could we just document that we expect StringMapping to contain lowercase strings
already? (GetEnvironmentVariablesMapping guarantees that for you, no?)

[Patrick Monette, 2017/02/28 23:37:38]

Indeed. Done.

+    if (base::StartsWith(lower_string, prefix, base::CompareCase::SENSITIVE)) {

[chrisha, 2017/02/28 18:51:29]

Do we have expectations that the paths in |prefix_mapping| have trailing
slashes? Should we? Can you document this in the .h files?

[Patrick Monette, 2017/02/28 23:37:38]

I don't think this function needs to expect paths with or without trailing
slashes. I made it so that GetEnvironmentVariablesMapping() always return
without trailing slashes so it'll be consistent.

+      base::string16 collapsed_string = lower_string;
+      base::ReplaceFirstSubstringAfterOffset(&collapsed_string, 0, prefix,
+                                             mapping.second);
+      size_t length = collapsed_string.length() - mapping.second.length();
+      if (length < min_length) {

[chrisha, 2017/02/28 18:51:28]

We're only doing the collapsing if it's shorter? We should always be doing this
as we're trying to "normalize" paths to remove the effects of localization.

[Patrick Monette, 2017/02/28 23:37:38]

Chatted offline. Ignored.

+        *string = collapsed_string;
+        min_length = length;
+      }
+    }
+  }
+}