Add m-esr52 at 52.6.0

1 files changed, 1537 insertions, 0 deletions

diff --git a/uriloader/exthandler/unix/nsOSHelperAppService.cpp b/uriloader/exthandler/unix/nsOSHelperAppService.cpp
new file mode 100644
index 000000000..84e1cf5b0
--- /dev/null
+++ b/uriloader/exthandler/unix/nsOSHelperAppService.cpp
@@ -0,0 +1,1537 @@
+/* -*- Mode: C++; tab-width: 3; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#if defined(MOZ_ENABLE_CONTENTACTION)
+#include <contentaction/contentaction.h>
+#include <QString>
+#endif
+
+#include "nsOSHelperAppService.h"
+#include "nsMIMEInfoUnix.h"
+#ifdef MOZ_WIDGET_GTK
+#include "nsGNOMERegistry.h"
+#endif
+#include "nsISupports.h"
+#include "nsString.h"
+#include "nsReadableUtils.h"
+#include "nsUnicharUtils.h"
+#include "nsXPIDLString.h"
+#include "nsIURL.h"
+#include "nsIFileStreams.h"
+#include "nsILineInputStream.h"
+#include "nsIFile.h"
+#include "nsIProcess.h"
+#include "nsNetCID.h"
+#include "nsXPCOM.h"
+#include "nsISupportsPrimitives.h"
+#include "nsCRT.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsDirectoryServiceUtils.h"
+#include "prenv.h"      // for PR_GetEnv()
+#include "nsAutoPtr.h"
+#include "mozilla/Preferences.h"
+
+using namespace mozilla;
+
+#define LOG(args) MOZ_LOG(mLog, mozilla::LogLevel::Debug, args)
+#define LOG_ENABLED() MOZ_LOG_TEST(mLog, mozilla::LogLevel::Debug)
+
+static nsresult
+FindSemicolon(nsAString::const_iterator& aSemicolon_iter,
+              const nsAString::const_iterator& aEnd_iter);
+static nsresult
+ParseMIMEType(const nsAString::const_iterator& aStart_iter,
+              nsAString::const_iterator& aMajorTypeStart,
+              nsAString::const_iterator& aMajorTypeEnd,
+              nsAString::const_iterator& aMinorTypeStart,
+              nsAString::const_iterator& aMinorTypeEnd,
+              const nsAString::const_iterator& aEnd_iter);
+
+inline bool
+IsNetscapeFormat(const nsACString& aBuffer);
+
+nsOSHelperAppService::nsOSHelperAppService() : nsExternalHelperAppService()
+{
+  mode_t mask = umask(0777);
+  umask(mask);
+  mPermissions = 0666 & ~mask;
+}
+
+nsOSHelperAppService::~nsOSHelperAppService()
+{}
+
+/*
+ * Take a command with all the mailcap escapes in it and unescape it
+ * Ideally this needs the mime type, mime type options, and location of the
+ * temporary file, but this last can't be got from here
+ */
+// static
+nsresult
+nsOSHelperAppService::UnescapeCommand(const nsAString& aEscapedCommand,
+                                      const nsAString& aMajorType,
+                                      const nsAString& aMinorType,
+                                      nsACString& aUnEscapedCommand) {
+  LOG(("-- UnescapeCommand"));
+  LOG(("Command to escape: '%s'\n",
+       NS_LossyConvertUTF16toASCII(aEscapedCommand).get()));
+  //  XXX This function will need to get the mime type and various stuff like that being passed in to work properly
+
+  LOG(("UnescapeCommand really needs some work -- it should actually do some unescaping\n"));
+
+  CopyUTF16toUTF8(aEscapedCommand, aUnEscapedCommand);
+  LOG(("Escaped command: '%s'\n",
+       PromiseFlatCString(aUnEscapedCommand).get()));
+  return NS_OK;
+}
+
+/* Put aSemicolon_iter at the first non-escaped semicolon after
+ * aStart_iter but before aEnd_iter
+ */
+
+static nsresult
+FindSemicolon(nsAString::const_iterator& aSemicolon_iter,
+              const nsAString::const_iterator& aEnd_iter) {
+  bool semicolonFound = false;
+  while (aSemicolon_iter != aEnd_iter && !semicolonFound) {
+    switch(*aSemicolon_iter) {
+    case '\\':
+      aSemicolon_iter.advance(2);
+      break;
+    case ';':
+      semicolonFound = true;
+      break;
+    default:
+      ++aSemicolon_iter;
+      break;
+    }
+  }
+  return NS_OK;
+}
+
+static nsresult
+ParseMIMEType(const nsAString::const_iterator& aStart_iter,
+              nsAString::const_iterator& aMajorTypeStart,
+              nsAString::const_iterator& aMajorTypeEnd,
+              nsAString::const_iterator& aMinorTypeStart,
+              nsAString::const_iterator& aMinorTypeEnd,
+              const nsAString::const_iterator& aEnd_iter) {
+  nsAString::const_iterator iter(aStart_iter);
+
+  // skip leading whitespace
+  while (iter != aEnd_iter && nsCRT::IsAsciiSpace(*iter)) {
+    ++iter;
+  }
+
+  if (iter == aEnd_iter) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  aMajorTypeStart = iter;
+
+  // find major/minor separator ('/')
+  while (iter != aEnd_iter && *iter != '/') {
+    ++iter;
+  }
+
+  if (iter == aEnd_iter) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  aMajorTypeEnd = iter;
+
+  // skip '/'
+  ++iter;
+
+  if (iter == aEnd_iter) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  aMinorTypeStart = iter;
+
+  // find end of minor type, delimited by whitespace or ';'
+  while (iter != aEnd_iter && !nsCRT::IsAsciiSpace(*iter) && *iter != ';') {
+    ++iter;
+  }
+
+  aMinorTypeEnd = iter;
+
+  return NS_OK;
+}
+
+// static
+nsresult
+nsOSHelperAppService::GetFileLocation(const char* aPrefName,
+                                      const char* aEnvVarName,
+                                      nsAString& aFileLocation) {
+  LOG(("-- GetFileLocation.  Pref: '%s'  EnvVar: '%s'\n",
+       aPrefName,
+       aEnvVarName));
+  NS_PRECONDITION(aPrefName, "Null pref name passed; don't do that!");
+
+  aFileLocation.Truncate();
+  /* The lookup order is:
+     1) user pref
+     2) env var
+     3) pref
+  */
+  NS_ENSURE_TRUE(Preferences::GetRootBranch(), NS_ERROR_FAILURE);
+
+  /*
+    If we have an env var we should check whether the pref is a user
+    pref.  If we do not, we don't care.
+  */
+  if (Preferences::HasUserValue(aPrefName) &&
+      NS_SUCCEEDED(Preferences::GetString(aPrefName, &aFileLocation))) {
+    return NS_OK;
+  }
+
+  if (aEnvVarName && *aEnvVarName) {
+    char* prefValue = PR_GetEnv(aEnvVarName);
+    if (prefValue && *prefValue) {
+      // the pref is in the system charset and it's a filepath... The
+      // natural way to do the charset conversion is by just initing
+      // an nsIFile with the native path and asking it for the Unicode
+      // version.
+      nsresult rv;
+      nsCOMPtr<nsIFile> file(do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv));
+      NS_ENSURE_SUCCESS(rv, rv);
+
+      rv = file->InitWithNativePath(nsDependentCString(prefValue));
+      NS_ENSURE_SUCCESS(rv, rv);
+
+      rv = file->GetPath(aFileLocation);
+      NS_ENSURE_SUCCESS(rv, rv);
+
+      return NS_OK;
+    }
+  }
+
+  return Preferences::GetString(aPrefName, &aFileLocation);
+}
+
+
+/* Get the mime.types file names from prefs and look up info in them
+   based on extension */
+// static
+nsresult
+nsOSHelperAppService::LookUpTypeAndDescription(const nsAString& aFileExtension,
+                                               nsAString& aMajorType,
+                                               nsAString& aMinorType,
+                                               nsAString& aDescription,
+                                               bool aUserData) {
+  LOG(("-- LookUpTypeAndDescription for extension '%s'\n",
+       NS_LossyConvertUTF16toASCII(aFileExtension).get()));
+  nsresult rv = NS_OK;
+  nsAutoString mimeFileName;
+
+  const char* filenamePref = aUserData ?
+    "helpers.private_mime_types_file" : "helpers.global_mime_types_file";
+
+  rv = GetFileLocation(filenamePref, nullptr, mimeFileName);
+  if (NS_SUCCEEDED(rv) && !mimeFileName.IsEmpty()) {
+    rv = GetTypeAndDescriptionFromMimetypesFile(mimeFileName,
+                                                aFileExtension,
+                                                aMajorType,
+                                                aMinorType,
+                                                aDescription);
+  } else {
+    rv = NS_ERROR_NOT_AVAILABLE;
+  }
+
+  return rv;
+}
+
+inline bool
+IsNetscapeFormat(const nsACString& aBuffer) {
+  return StringBeginsWith(aBuffer, NS_LITERAL_CSTRING("#--Netscape Communications Corporation MIME Information")) ||
+         StringBeginsWith(aBuffer, NS_LITERAL_CSTRING("#--MCOM MIME Information"));
+}
+
+/*
+ * Create a file stream and line input stream for the filename.
+ * Leaves the first line of the file in aBuffer and sets the format to
+ *  true for netscape files and false for normail ones
+ */
+// static
+nsresult
+nsOSHelperAppService::CreateInputStream(const nsAString& aFilename,
+                                        nsIFileInputStream ** aFileInputStream,
+                                        nsILineInputStream ** aLineInputStream,
+                                        nsACString& aBuffer,
+                                        bool * aNetscapeFormat,
+                                        bool * aMore) {
+  LOG(("-- CreateInputStream"));
+  nsresult rv = NS_OK;
+
+  nsCOMPtr<nsIFile> file(do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv));
+  if (NS_FAILED(rv))
+    return rv;
+  rv = file->InitWithPath(aFilename);
+  if (NS_FAILED(rv))
+    return rv;
+
+  nsCOMPtr<nsIFileInputStream> fileStream(do_CreateInstance(NS_LOCALFILEINPUTSTREAM_CONTRACTID, &rv));
+  if (NS_FAILED(rv))
+    return rv;
+  rv = fileStream->Init(file, -1, -1, false);
+  if (NS_FAILED(rv))
+    return rv;
+
+  nsCOMPtr<nsILineInputStream> lineStream(do_QueryInterface(fileStream, &rv));
+
+  if (NS_FAILED(rv)) {
+    LOG(("Interface trouble in stream land!"));
+    return rv;
+  }
+
+  rv = lineStream->ReadLine(aBuffer, aMore);
+  if (NS_FAILED(rv)) {
+    fileStream->Close();
+    return rv;
+  }
+
+  *aNetscapeFormat = IsNetscapeFormat(aBuffer);
+
+  *aFileInputStream = fileStream;
+  NS_ADDREF(*aFileInputStream);
+  *aLineInputStream = lineStream;
+  NS_ADDREF(*aLineInputStream);
+
+  return NS_OK;
+}
+
+/* Open the file, read the first line, decide what type of file it is,
+   then get info based on extension */
+// static
+nsresult
+nsOSHelperAppService::GetTypeAndDescriptionFromMimetypesFile(const nsAString& aFilename,
+                                                             const nsAString& aFileExtension,
+                                                             nsAString& aMajorType,
+                                                             nsAString& aMinorType,
+                                                             nsAString& aDescription) {
+  LOG(("-- GetTypeAndDescriptionFromMimetypesFile\n"));
+  LOG(("Getting type and description from types file '%s'\n",
+       NS_LossyConvertUTF16toASCII(aFilename).get()));
+  LOG(("Using extension '%s'\n",
+       NS_LossyConvertUTF16toASCII(aFileExtension).get()));
+  nsresult rv = NS_OK;
+  nsCOMPtr<nsIFileInputStream> mimeFile;
+  nsCOMPtr<nsILineInputStream> mimeTypes;
+  bool netscapeFormat;
+  nsAutoString buf;
+  nsAutoCString cBuf;
+  bool more = false;
+  rv = CreateInputStream(aFilename, getter_AddRefs(mimeFile), getter_AddRefs(mimeTypes),
+                         cBuf, &netscapeFormat, &more);
+
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+
+  nsAutoString extensions;
+  nsString entry;
+  entry.SetCapacity(100);
+  nsAString::const_iterator majorTypeStart, majorTypeEnd,
+                            minorTypeStart, minorTypeEnd,
+                            descriptionStart, descriptionEnd;
+
+  do {
+    CopyASCIItoUTF16(cBuf, buf);
+    // read through, building up an entry.  If we finish an entry, check for
+    // a match and return out of the loop if we match
+
+    // skip comments and empty lines
+    if (!buf.IsEmpty() && buf.First() != '#') {
+      entry.Append(buf);
+      if (entry.Last() == '\\') {
+        entry.Truncate(entry.Length() - 1);
+        entry.Append(char16_t(' '));  // in case there is no trailing whitespace on this line
+      } else {  // we have a full entry
+        LOG(("Current entry: '%s'\n",
+             NS_LossyConvertUTF16toASCII(entry).get()));
+        if (netscapeFormat) {
+          rv = ParseNetscapeMIMETypesEntry(entry,
+                                           majorTypeStart, majorTypeEnd,
+                                           minorTypeStart, minorTypeEnd,
+                                           extensions,
+                                           descriptionStart, descriptionEnd);
+          if (NS_FAILED(rv)) {
+            // We sometimes get things like RealPlayer appending
+            // "normal" entries to "Netscape" .mime.types files.  Try
+            // to handle that.  Bug 106381.
+            LOG(("Bogus entry; trying 'normal' mode\n"));
+            rv = ParseNormalMIMETypesEntry(entry,
+                                           majorTypeStart, majorTypeEnd,
+                                           minorTypeStart, minorTypeEnd,
+                                           extensions,
+                                           descriptionStart, descriptionEnd);
+          }
+        } else {
+          rv = ParseNormalMIMETypesEntry(entry,
+                                         majorTypeStart, majorTypeEnd,
+                                         minorTypeStart, minorTypeEnd,
+                                         extensions,
+                                         descriptionStart, descriptionEnd);
+          if (NS_FAILED(rv)) {
+            // We sometimes get things like StarOffice prepending
+            // "normal" entries to "Netscape" .mime.types files.  Try
+            // to handle that.  Bug 136670.
+            LOG(("Bogus entry; trying 'Netscape' mode\n"));
+            rv = ParseNetscapeMIMETypesEntry(entry,
+                                             majorTypeStart, majorTypeEnd,
+                                             minorTypeStart, minorTypeEnd,
+                                             extensions,
+                                             descriptionStart, descriptionEnd);
+          }
+        }
+
+        if (NS_SUCCEEDED(rv)) { // entry parses
+          nsAString::const_iterator start, end;
+          extensions.BeginReading(start);
+          extensions.EndReading(end);
+          nsAString::const_iterator iter(start);
+
+          while (start != end) {
+            FindCharInReadable(',', iter, end);
+            if (Substring(start, iter).Equals(aFileExtension,
+                                              nsCaseInsensitiveStringComparator())) {
+              // it's a match.  Assign the type and description and run
+              aMajorType.Assign(Substring(majorTypeStart, majorTypeEnd));
+              aMinorType.Assign(Substring(minorTypeStart, minorTypeEnd));
+              aDescription.Assign(Substring(descriptionStart, descriptionEnd));
+              mimeFile->Close();
+              return NS_OK;
+            }
+            if (iter != end) {
+              ++iter;
+            }
+            start = iter;
+          }
+        } else {
+          LOG(("Failed to parse entry: %s\n", NS_LossyConvertUTF16toASCII(entry).get()));
+        }
+        // truncate the entry for the next iteration
+        entry.Truncate();
+      }
+    }
+    if (!more) {
+      rv = NS_ERROR_NOT_AVAILABLE;
+      break;
+    }
+    // read the next line
+    rv = mimeTypes->ReadLine(cBuf, &more);
+  } while (NS_SUCCEEDED(rv));
+
+  mimeFile->Close();
+  return rv;
+}
+
+/* Get the mime.types file names from prefs and look up info in them
+   based on mimetype  */
+// static
+nsresult
+nsOSHelperAppService::LookUpExtensionsAndDescription(const nsAString& aMajorType,
+                                                     const nsAString& aMinorType,
+                                                     nsAString& aFileExtensions,
+                                                     nsAString& aDescription) {
+  LOG(("-- LookUpExtensionsAndDescription for type '%s/%s'\n",
+       NS_LossyConvertUTF16toASCII(aMajorType).get(),
+       NS_LossyConvertUTF16toASCII(aMinorType).get()));
+  nsresult rv = NS_OK;
+  nsAutoString mimeFileName;
+
+  rv = GetFileLocation("helpers.private_mime_types_file", nullptr, mimeFileName);
+  if (NS_SUCCEEDED(rv) && !mimeFileName.IsEmpty()) {
+    rv = GetExtensionsAndDescriptionFromMimetypesFile(mimeFileName,
+                                                      aMajorType,
+                                                      aMinorType,
+                                                      aFileExtensions,
+                                                      aDescription);
+  } else {
+    rv = NS_ERROR_NOT_AVAILABLE;
+  }
+  if (NS_FAILED(rv) || aFileExtensions.IsEmpty()) {
+    rv = GetFileLocation("helpers.global_mime_types_file",
+                         nullptr, mimeFileName);
+    if (NS_SUCCEEDED(rv) && !mimeFileName.IsEmpty()) {
+      rv = GetExtensionsAndDescriptionFromMimetypesFile(mimeFileName,
+                                                        aMajorType,
+                                                        aMinorType,
+                                                        aFileExtensions,
+                                                        aDescription);
+    } else {
+      rv = NS_ERROR_NOT_AVAILABLE;
+    }
+  }
+  return rv;
+}
+
+/* Open the file, read the first line, decide what type of file it is,
+   then get info based on extension */
+// static
+nsresult
+nsOSHelperAppService::GetExtensionsAndDescriptionFromMimetypesFile(const nsAString& aFilename,
+                                                                   const nsAString& aMajorType,
+                                                                   const nsAString& aMinorType,
+                                                                   nsAString& aFileExtensions,
+                                                                   nsAString& aDescription) {
+  LOG(("-- GetExtensionsAndDescriptionFromMimetypesFile\n"));
+  LOG(("Getting extensions and description from types file '%s'\n",
+       NS_LossyConvertUTF16toASCII(aFilename).get()));
+  LOG(("Using type '%s/%s'\n",
+       NS_LossyConvertUTF16toASCII(aMajorType).get(),
+       NS_LossyConvertUTF16toASCII(aMinorType).get()));
+
+  nsresult rv = NS_OK;
+  nsCOMPtr<nsIFileInputStream> mimeFile;
+  nsCOMPtr<nsILineInputStream> mimeTypes;
+  bool netscapeFormat;
+  nsAutoCString cBuf;
+  nsAutoString buf;
+  bool more = false;
+  rv = CreateInputStream(aFilename, getter_AddRefs(mimeFile), getter_AddRefs(mimeTypes),
+                         cBuf, &netscapeFormat, &more);
+
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+
+  nsAutoString extensions;
+  nsString entry;
+  entry.SetCapacity(100);
+  nsAString::const_iterator majorTypeStart, majorTypeEnd,
+                            minorTypeStart, minorTypeEnd,
+                            descriptionStart, descriptionEnd;
+
+  do {
+    CopyASCIItoUTF16(cBuf, buf);
+    // read through, building up an entry.  If we finish an entry, check for
+    // a match and return out of the loop if we match
+
+    // skip comments and empty lines
+    if (!buf.IsEmpty() && buf.First() != '#') {
+      entry.Append(buf);
+      if (entry.Last() == '\\') {
+        entry.Truncate(entry.Length() - 1);
+        entry.Append(char16_t(' '));  // in case there is no trailing whitespace on this line
+      } else {  // we have a full entry
+        LOG(("Current entry: '%s'\n",
+             NS_LossyConvertUTF16toASCII(entry).get()));
+        if (netscapeFormat) {
+          rv = ParseNetscapeMIMETypesEntry(entry,
+                                           majorTypeStart, majorTypeEnd,
+                                           minorTypeStart, minorTypeEnd,
+                                           extensions,
+                                           descriptionStart, descriptionEnd);
+
+          if (NS_FAILED(rv)) {
+            // We sometimes get things like RealPlayer appending
+            // "normal" entries to "Netscape" .mime.types files.  Try
+            // to handle that.  Bug 106381.
+            LOG(("Bogus entry; trying 'normal' mode\n"));
+            rv = ParseNormalMIMETypesEntry(entry,
+                                           majorTypeStart, majorTypeEnd,
+                                           minorTypeStart, minorTypeEnd,
+                                           extensions,
+                                           descriptionStart, descriptionEnd);
+          }
+        } else {
+          rv = ParseNormalMIMETypesEntry(entry,
+                                         majorTypeStart, majorTypeEnd,
+                                         minorTypeStart,
+                                         minorTypeEnd, extensions,
+                                         descriptionStart, descriptionEnd);
+
+          if (NS_FAILED(rv)) {
+            // We sometimes get things like StarOffice prepending
+            // "normal" entries to "Netscape" .mime.types files.  Try
+            // to handle that.  Bug 136670.
+            LOG(("Bogus entry; trying 'Netscape' mode\n"));
+            rv = ParseNetscapeMIMETypesEntry(entry,
+                                             majorTypeStart, majorTypeEnd,
+                                             minorTypeStart, minorTypeEnd,
+                                             extensions,
+                                             descriptionStart, descriptionEnd);
+          }
+        }
+
+        if (NS_SUCCEEDED(rv) &&
+            Substring(majorTypeStart,
+                      majorTypeEnd).Equals(aMajorType,
+                                           nsCaseInsensitiveStringComparator())&&
+            Substring(minorTypeStart,
+                      minorTypeEnd).Equals(aMinorType,
+                                           nsCaseInsensitiveStringComparator())) {
+          // it's a match
+          aFileExtensions.Assign(extensions);
+          aDescription.Assign(Substring(descriptionStart, descriptionEnd));
+          mimeFile->Close();
+          return NS_OK;
+        } else if (NS_FAILED(rv)) {
+          LOG(("Failed to parse entry: %s\n", NS_LossyConvertUTF16toASCII(entry).get()));
+        }
+
+        entry.Truncate();
+      }
+    }
+    if (!more) {
+      rv = NS_ERROR_NOT_AVAILABLE;
+      break;
+    }
+    // read the next line
+    rv = mimeTypes->ReadLine(cBuf, &more);
+  } while (NS_SUCCEEDED(rv));
+
+  mimeFile->Close();
+  return rv;
+}
+
+/*
+ * This parses a Netscape format mime.types entry.  There are two
+ * possible formats:
+ *
+ * type=foo/bar; options exts="baz" description="Some type"
+ *
+ * and
+ *
+ * type=foo/bar; options description="Some type" exts="baz"
+ */
+// static
+nsresult
+nsOSHelperAppService::ParseNetscapeMIMETypesEntry(const nsAString& aEntry,
+                                                  nsAString::const_iterator& aMajorTypeStart,
+                                                  nsAString::const_iterator& aMajorTypeEnd,
+                                                  nsAString::const_iterator& aMinorTypeStart,
+                                                  nsAString::const_iterator& aMinorTypeEnd,
+                                                  nsAString& aExtensions,
+                                                  nsAString::const_iterator& aDescriptionStart,
+                                                  nsAString::const_iterator& aDescriptionEnd) {
+  LOG(("-- ParseNetscapeMIMETypesEntry\n"));
+  NS_ASSERTION(!aEntry.IsEmpty(), "Empty Netscape MIME types entry being parsed.");
+
+  nsAString::const_iterator start_iter, end_iter, match_start, match_end;
+
+  aEntry.BeginReading(start_iter);
+  aEntry.EndReading(end_iter);
+
+  // skip trailing whitespace
+  do {
+    --end_iter;
+  } while (end_iter != start_iter &&
+           nsCRT::IsAsciiSpace(*end_iter));
+  // if we're pointing to a quote, don't advance -- we don't want to
+  // include the quote....
+  if (*end_iter != '"')
+    ++end_iter;
+  match_start = start_iter;
+  match_end = end_iter;
+
+  // Get the major and minor types
+  // First the major type
+  if (! FindInReadable(NS_LITERAL_STRING("type="), match_start, match_end)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  match_start = match_end;
+
+  while (match_end != end_iter &&
+         *match_end != '/') {
+    ++match_end;
+  }
+  if (match_end == end_iter) {
+    return NS_ERROR_FAILURE;
+  }
+
+  aMajorTypeStart = match_start;
+  aMajorTypeEnd = match_end;
+
+  // now the minor type
+  if (++match_end == end_iter) {
+    return NS_ERROR_FAILURE;
+  }
+
+  match_start = match_end;
+
+  while (match_end != end_iter &&
+         !nsCRT::IsAsciiSpace(*match_end) &&
+         *match_end != ';') {
+    ++match_end;
+  }
+  if (match_end == end_iter) {
+    return NS_ERROR_FAILURE;
+  }
+
+  aMinorTypeStart = match_start;
+  aMinorTypeEnd = match_end;
+
+  // ignore everything up to the end of the mime type from here on
+  start_iter = match_end;
+
+  // get the extensions
+  match_start = match_end;
+  match_end = end_iter;
+  if (FindInReadable(NS_LITERAL_STRING("exts="), match_start, match_end)) {
+    nsAString::const_iterator extStart, extEnd;
+
+    if (match_end == end_iter ||
+        (*match_end == '"' && ++match_end == end_iter)) {
+      return NS_ERROR_FAILURE;
+    }
+
+    extStart = match_end;
+    match_start = extStart;
+    match_end = end_iter;
+    if (FindInReadable(NS_LITERAL_STRING("desc=\""), match_start, match_end)) {
+      // exts= before desc=, so we have to find the actual end of the extensions
+      extEnd = match_start;
+      if (extEnd == extStart) {
+        return NS_ERROR_FAILURE;
+      }
+
+      do {
+        --extEnd;
+      } while (extEnd != extStart &&
+               nsCRT::IsAsciiSpace(*extEnd));
+
+      if (extEnd != extStart && *extEnd == '"') {
+        --extEnd;
+      }
+    } else {
+      // desc= before exts=, so we can use end_iter as the end of the extensions
+      extEnd = end_iter;
+    }
+    aExtensions = Substring(extStart, extEnd);
+  } else {
+    // no extensions
+    aExtensions.Truncate();
+  }
+
+  // get the description
+  match_start = start_iter;
+  match_end = end_iter;
+  if (FindInReadable(NS_LITERAL_STRING("desc=\""), match_start, match_end)) {
+    aDescriptionStart = match_end;
+    match_start = aDescriptionStart;
+    match_end = end_iter;
+    if (FindInReadable(NS_LITERAL_STRING("exts="), match_start, match_end)) {
+      // exts= after desc=, so have to find actual end of description
+      aDescriptionEnd = match_start;
+      if (aDescriptionEnd == aDescriptionStart) {
+        return NS_ERROR_FAILURE;
+      }
+
+      do {
+        --aDescriptionEnd;
+      } while (aDescriptionEnd != aDescriptionStart &&
+               nsCRT::IsAsciiSpace(*aDescriptionEnd));
+
+      if (aDescriptionStart != aDescriptionStart && *aDescriptionEnd == '"') {
+        --aDescriptionEnd;
+      }
+    } else {
+      // desc= after exts=, so use end_iter for the description end
+      aDescriptionEnd = end_iter;
+    }
+  } else {
+    // no description
+    aDescriptionStart = start_iter;
+    aDescriptionEnd = start_iter;
+  }
+
+  return NS_OK;
+}
+
+/*
+ * This parses a normal format mime.types entry.  The format is:
+ *
+ * major/minor    ext1 ext2 ext3
+ */
+// static
+nsresult
+nsOSHelperAppService::ParseNormalMIMETypesEntry(const nsAString& aEntry,
+                                                nsAString::const_iterator& aMajorTypeStart,
+                                                nsAString::const_iterator& aMajorTypeEnd,
+                                                nsAString::const_iterator& aMinorTypeStart,
+                                                nsAString::const_iterator& aMinorTypeEnd,
+                                                nsAString& aExtensions,
+                                                nsAString::const_iterator& aDescriptionStart,
+                                                nsAString::const_iterator& aDescriptionEnd) {
+  LOG(("-- ParseNormalMIMETypesEntry\n"));
+  NS_ASSERTION(!aEntry.IsEmpty(), "Empty Normal MIME types entry being parsed.");
+
+  nsAString::const_iterator start_iter, end_iter, iter;
+
+  aEntry.BeginReading(start_iter);
+  aEntry.EndReading(end_iter);
+
+  // no description
+  aDescriptionStart = start_iter;
+  aDescriptionEnd = start_iter;
+
+  // skip leading whitespace
+  while (start_iter != end_iter && nsCRT::IsAsciiSpace(*start_iter)) {
+    ++start_iter;
+  }
+  if (start_iter == end_iter) {
+    return NS_ERROR_FAILURE;
+  }
+  // skip trailing whitespace
+  do {
+    --end_iter;
+  } while (end_iter != start_iter && nsCRT::IsAsciiSpace(*end_iter));
+
+  ++end_iter; // point to first whitespace char (or to end of string)
+  iter = start_iter;
+
+  // get the major type
+  if (! FindCharInReadable('/', iter, end_iter))
+    return NS_ERROR_FAILURE;
+
+  nsAString::const_iterator equals_sign_iter(start_iter);
+  if (FindCharInReadable('=', equals_sign_iter, iter))
+    return NS_ERROR_FAILURE; // see bug 136670
+
+  aMajorTypeStart = start_iter;
+  aMajorTypeEnd = iter;
+
+  // get the minor type
+  if (++iter == end_iter) {
+    return NS_ERROR_FAILURE;
+  }
+  start_iter = iter;
+
+  while (iter != end_iter && !nsCRT::IsAsciiSpace(*iter)) {
+    ++iter;
+  }
+  aMinorTypeStart = start_iter;
+  aMinorTypeEnd = iter;
+
+  // get the extensions
+  aExtensions.Truncate();
+  while (iter != end_iter) {
+    while (iter != end_iter && nsCRT::IsAsciiSpace(*iter)) {
+      ++iter;
+    }
+
+    start_iter = iter;
+    while (iter != end_iter && !nsCRT::IsAsciiSpace(*iter)) {
+      ++iter;
+    }
+    aExtensions.Append(Substring(start_iter, iter));
+    if (iter != end_iter) { // not the last extension
+      aExtensions.Append(char16_t(','));
+    }
+  }
+
+  return NS_OK;
+}
+
+// static
+nsresult
+nsOSHelperAppService::LookUpHandlerAndDescription(const nsAString& aMajorType,
+                                                  const nsAString& aMinorType,
+                                                  nsAString& aHandler,
+                                                  nsAString& aDescription,
+                                                  nsAString& aMozillaFlags) {
+
+  // The mailcap lookup is two-pass to handle the case of mailcap files
+  // that have something like:
+  //
+  // text/*; emacs %s
+  // text/rtf; soffice %s
+  //
+  // in that order.  We want to pick up "soffice" for text/rtf in such cases
+  nsresult rv = DoLookUpHandlerAndDescription(aMajorType,
+                                              aMinorType,
+                                              aHandler,
+                                              aDescription,
+                                              aMozillaFlags,
+                                              true);
+  if (NS_FAILED(rv)) {
+    rv = DoLookUpHandlerAndDescription(aMajorType,
+                                       aMinorType,
+                                       aHandler,
+                                       aDescription,
+                                       aMozillaFlags,
+                                       false);
+  }
+
+  // maybe we have an entry for "aMajorType/*"?
+  if (NS_FAILED(rv)) {
+    rv = DoLookUpHandlerAndDescription(aMajorType,
+                                       NS_LITERAL_STRING("*"),
+                                       aHandler,
+                                       aDescription,
+                                       aMozillaFlags,
+                                       true);
+  }
+
+  if (NS_FAILED(rv)) {
+    rv = DoLookUpHandlerAndDescription(aMajorType,
+                                       NS_LITERAL_STRING("*"),
+                                       aHandler,
+                                       aDescription,
+                                       aMozillaFlags,
+                                       false);
+  }
+
+  return rv;
+}
+
+// static
+nsresult
+nsOSHelperAppService::DoLookUpHandlerAndDescription(const nsAString& aMajorType,
+                                                    const nsAString& aMinorType,
+                                                    nsAString& aHandler,
+                                                    nsAString& aDescription,
+                                                    nsAString& aMozillaFlags,
+                                                    bool aUserData) {
+  LOG(("-- LookUpHandlerAndDescription for type '%s/%s'\n",
+       NS_LossyConvertUTF16toASCII(aMajorType).get(),
+       NS_LossyConvertUTF16toASCII(aMinorType).get()));
+  nsresult rv = NS_OK;
+  nsAutoString mailcapFileName;
+
+  const char * filenamePref = aUserData ?
+    "helpers.private_mailcap_file" : "helpers.global_mailcap_file";
+  const char * filenameEnvVar = aUserData ?
+    "PERSONAL_MAILCAP" : "MAILCAP";
+
+  rv = GetFileLocation(filenamePref, filenameEnvVar, mailcapFileName);
+  if (NS_SUCCEEDED(rv) && !mailcapFileName.IsEmpty()) {
+    rv = GetHandlerAndDescriptionFromMailcapFile(mailcapFileName,
+                                                 aMajorType,
+                                                 aMinorType,
+                                                 aHandler,
+                                                 aDescription,
+                                                 aMozillaFlags);
+  } else {
+    rv = NS_ERROR_NOT_AVAILABLE;
+  }
+
+  return rv;
+}
+
+// static
+nsresult
+nsOSHelperAppService::GetHandlerAndDescriptionFromMailcapFile(const nsAString& aFilename,
+                                                              const nsAString& aMajorType,
+                                                              const nsAString& aMinorType,
+                                                              nsAString& aHandler,
+                                                              nsAString& aDescription,
+                                                              nsAString& aMozillaFlags) {
+
+  LOG(("-- GetHandlerAndDescriptionFromMailcapFile\n"));
+  LOG(("Getting handler and description from mailcap file '%s'\n",
+       NS_LossyConvertUTF16toASCII(aFilename).get()));
+  LOG(("Using type '%s/%s'\n",
+       NS_LossyConvertUTF16toASCII(aMajorType).get(),
+       NS_LossyConvertUTF16toASCII(aMinorType).get()));
+
+  nsresult rv = NS_OK;
+  bool more = false;
+
+  nsCOMPtr<nsIFile> file(do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv));
+  if (NS_FAILED(rv))
+    return rv;
+  rv = file->InitWithPath(aFilename);
+  if (NS_FAILED(rv))
+    return rv;
+
+  nsCOMPtr<nsIFileInputStream> mailcapFile(do_CreateInstance(NS_LOCALFILEINPUTSTREAM_CONTRACTID, &rv));
+  if (NS_FAILED(rv))
+    return rv;
+  rv = mailcapFile->Init(file, -1, -1, false);
+  if (NS_FAILED(rv))
+    return rv;
+
+  nsCOMPtr<nsILineInputStream> mailcap (do_QueryInterface(mailcapFile, &rv));
+
+  if (NS_FAILED(rv)) {
+    LOG(("Interface trouble in stream land!"));
+    return rv;
+  }
+
+  nsString entry, buffer;
+  nsAutoCString cBuffer;
+  entry.SetCapacity(128);
+  cBuffer.SetCapacity(80);
+  rv = mailcap->ReadLine(cBuffer, &more);
+  if (NS_FAILED(rv)) {
+    mailcapFile->Close();
+    return rv;
+  }
+
+  do {  // return on end-of-file in the loop
+
+    CopyASCIItoUTF16(cBuffer, buffer);
+    if (!buffer.IsEmpty() && buffer.First() != '#') {
+      entry.Append(buffer);
+      if (entry.Last() == '\\') {  // entry continues on next line
+        entry.Truncate(entry.Length()-1);
+        entry.Append(char16_t(' ')); // in case there is no trailing whitespace on this line
+      } else {  // we have a full entry in entry.  Check it for the type
+        LOG(("Current entry: '%s'\n",
+             NS_LossyConvertUTF16toASCII(entry).get()));
+
+        nsAString::const_iterator semicolon_iter,
+                                  start_iter, end_iter,
+                                  majorTypeStart, majorTypeEnd,
+                                  minorTypeStart, minorTypeEnd;
+        entry.BeginReading(start_iter);
+        entry.EndReading(end_iter);
+        semicolon_iter = start_iter;
+        FindSemicolon(semicolon_iter, end_iter);
+        if (semicolon_iter != end_iter) { // we have something resembling a valid entry
+          rv = ParseMIMEType(start_iter, majorTypeStart, majorTypeEnd,
+                             minorTypeStart, minorTypeEnd, semicolon_iter);
+          if (NS_SUCCEEDED(rv) &&
+              Substring(majorTypeStart,
+                        majorTypeEnd).Equals(aMajorType,
+                                             nsCaseInsensitiveStringComparator()) &&
+              Substring(minorTypeStart,
+                        minorTypeEnd).Equals(aMinorType,
+                                             nsCaseInsensitiveStringComparator())) { // we have a match
+            bool match = true;
+            ++semicolon_iter;             // point at the first char past the semicolon
+            start_iter = semicolon_iter;  // handler string starts here
+            FindSemicolon(semicolon_iter, end_iter);
+            while (start_iter != semicolon_iter &&
+                   nsCRT::IsAsciiSpace(*start_iter)) {
+              ++start_iter;
+            }
+
+            LOG(("The real handler is: '%s'\n",
+                 NS_LossyConvertUTF16toASCII(Substring(start_iter,
+                                                      semicolon_iter)).get()));
+
+            // XXX ugly hack.  Just grab the executable name
+            nsAString::const_iterator end_handler_iter = semicolon_iter;
+            nsAString::const_iterator end_executable_iter = start_iter;
+            while (end_executable_iter != end_handler_iter &&
+                   !nsCRT::IsAsciiSpace(*end_executable_iter)) {
+              ++end_executable_iter;
+            }
+            // XXX End ugly hack
+
+            aHandler = Substring(start_iter, end_executable_iter);
+
+            nsAString::const_iterator start_option_iter, end_optionname_iter, equal_sign_iter;
+            bool equalSignFound;
+            while (match &&
+                   semicolon_iter != end_iter &&
+                   ++semicolon_iter != end_iter) { // there are options left and we still match
+              start_option_iter = semicolon_iter;
+              // skip over leading whitespace
+              while (start_option_iter != end_iter &&
+                     nsCRT::IsAsciiSpace(*start_option_iter)) {
+                ++start_option_iter;
+              }
+              if (start_option_iter == end_iter) { // nothing actually here
+                break;
+              }
+              semicolon_iter = start_option_iter;
+              FindSemicolon(semicolon_iter, end_iter);
+              equal_sign_iter = start_option_iter;
+              equalSignFound = false;
+              while (equal_sign_iter != semicolon_iter && !equalSignFound) {
+                switch(*equal_sign_iter) {
+                case '\\':
+                  equal_sign_iter.advance(2);
+                  break;
+                case '=':
+                  equalSignFound = true;
+                  break;
+                default:
+                  ++equal_sign_iter;
+                  break;
+                }
+              }
+              end_optionname_iter = start_option_iter;
+              // find end of option name
+              while (end_optionname_iter != equal_sign_iter &&
+                     !nsCRT::IsAsciiSpace(*end_optionname_iter)) {
+                ++end_optionname_iter;
+              }
+              nsDependentSubstring optionName(start_option_iter, end_optionname_iter);
+              if (equalSignFound) {
+                // This is an option that has a name and value
+                if (optionName.EqualsLiteral("description")) {
+                  aDescription = Substring(++equal_sign_iter, semicolon_iter);
+                } else if (optionName.EqualsLiteral("x-mozilla-flags")) {
+                  aMozillaFlags = Substring(++equal_sign_iter, semicolon_iter);
+                } else if (optionName.EqualsLiteral("test")) {
+                  nsAutoCString testCommand;
+                  rv = UnescapeCommand(Substring(++equal_sign_iter, semicolon_iter),
+                                       aMajorType,
+                                       aMinorType,
+                                       testCommand);
+                  if (NS_FAILED(rv))
+                    continue;
+                  nsCOMPtr<nsIProcess> process = do_CreateInstance(NS_PROCESS_CONTRACTID, &rv);
+                  if (NS_FAILED(rv))
+                    continue;
+                  nsCOMPtr<nsIFile> file(do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv));
+                  if (NS_FAILED(rv))
+                    continue;
+                  rv = file->InitWithNativePath(NS_LITERAL_CSTRING("/bin/sh"));
+                  if (NS_FAILED(rv))
+                    continue;
+                  rv = process->Init(file);
+                  if (NS_FAILED(rv))
+                    continue;
+                  const char *args[] = { "-c", testCommand.get() };
+                  LOG(("Running Test: %s\n", testCommand.get()));
+                  rv = process->Run(true, args, 2);
+                  if (NS_FAILED(rv))
+                    continue;
+                  int32_t exitValue;
+                  rv = process->GetExitValue(&exitValue);
+                  if (NS_FAILED(rv))
+                    continue;
+                  LOG(("Exit code: %d\n", exitValue));
+                  if (exitValue) {
+                    match = false;
+                  }
+                }
+              } else {
+                // This is an option that just has a name but no value (eg "copiousoutput")
+                if (optionName.EqualsLiteral("needsterminal")) {
+                  match = false;
+                }
+              }
+            }
+
+
+            if (match) { // we did not fail any test clauses; all is good
+              // get out of here
+              mailcapFile->Close();
+              return NS_OK;
+            } else { // pretend that this match never happened
+              aDescription.Truncate();
+              aMozillaFlags.Truncate();
+              aHandler.Truncate();
+            }
+          }
+        }
+        // zero out the entry for the next cycle
+        entry.Truncate();
+      }
+    }
+    if (!more) {
+      rv = NS_ERROR_NOT_AVAILABLE;
+      break;
+    }
+    rv = mailcap->ReadLine(cBuffer, &more);
+  } while (NS_SUCCEEDED(rv));
+  mailcapFile->Close();
+  return rv;
+}
+
+nsresult nsOSHelperAppService::OSProtocolHandlerExists(const char * aProtocolScheme, bool * aHandlerExists)
+{
+  LOG(("-- nsOSHelperAppService::OSProtocolHandlerExists for '%s'\n",
+       aProtocolScheme));
+  *aHandlerExists = false;
+
+#if defined(MOZ_ENABLE_CONTENTACTION)
+  // libcontentaction requires character ':' after scheme
+  ContentAction::Action action =
+    ContentAction::Action::defaultActionForScheme(QString(aProtocolScheme) + ':');
+
+  if (action.isValid())
+    *aHandlerExists = true;
+#endif
+
+#ifdef MOZ_WIDGET_GTK
+  // Check the GNOME registry for a protocol handler
+  *aHandlerExists = nsGNOMERegistry::HandlerExists(aProtocolScheme);
+#endif
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsOSHelperAppService::GetApplicationDescription(const nsACString& aScheme, nsAString& _retval)
+{
+#ifdef MOZ_WIDGET_GTK
+  nsGNOMERegistry::GetAppDescForScheme(aScheme, _retval);
+  return _retval.IsEmpty() ? NS_ERROR_NOT_AVAILABLE : NS_OK;
+#else
+  return NS_ERROR_NOT_AVAILABLE;
+#endif
+}
+
+nsresult nsOSHelperAppService::GetFileTokenForPath(const char16_t * platformAppPath, nsIFile ** aFile)
+{
+  LOG(("-- nsOSHelperAppService::GetFileTokenForPath: '%s'\n",
+       NS_LossyConvertUTF16toASCII(platformAppPath).get()));
+  if (! *platformAppPath) { // empty filename--return error
+    NS_WARNING("Empty filename passed in.");
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  // first check if the base class implementation finds anything
+  nsresult rv = nsExternalHelperAppService::GetFileTokenForPath(platformAppPath, aFile);
+  if (NS_SUCCEEDED(rv))
+    return rv;
+  // If the reason for failure was that the file doesn't exist, return too
+  // (because it means the path was absolute, and so that we shouldn't search in
+  // the path)
+  if (rv == NS_ERROR_FILE_NOT_FOUND)
+    return rv;
+
+  // If we get here, we really should have a relative path.
+  NS_ASSERTION(*platformAppPath != char16_t('/'), "Unexpected absolute path");
+
+  nsCOMPtr<nsIFile> localFile (do_CreateInstance(NS_LOCAL_FILE_CONTRACTID));
+
+  if (!localFile) return NS_ERROR_NOT_INITIALIZED;
+
+  bool exists = false;
+  // ugly hack.  Walk the PATH variable...
+  char* unixpath = PR_GetEnv("PATH");
+  nsAutoCString path(unixpath);
+
+  const char* start_iter = path.BeginReading(start_iter);
+  const char* colon_iter = start_iter;
+  const char* end_iter = path.EndReading(end_iter);
+
+  while (start_iter != end_iter && !exists) {
+    while (colon_iter != end_iter && *colon_iter != ':') {
+      ++colon_iter;
+    }
+    localFile->InitWithNativePath(Substring(start_iter, colon_iter));
+    rv = localFile->AppendRelativePath(nsDependentString(platformAppPath));
+    // Failing AppendRelativePath is a bad thing - it should basically always
+    // succeed given a relative path. Show a warning if it does fail.
+    // To prevent infinite loops when it does fail, return at this point.
+    NS_ENSURE_SUCCESS(rv, rv);
+    localFile->Exists(&exists);
+    if (!exists) {
+      if (colon_iter == end_iter) {
+        break;
+      }
+      ++colon_iter;
+      start_iter = colon_iter;
+    }
+  }
+
+  if (exists) {
+    rv = NS_OK;
+  } else {
+    rv = NS_ERROR_NOT_AVAILABLE;
+  }
+
+  *aFile = localFile;
+  NS_IF_ADDREF(*aFile);
+
+  return rv;
+}
+
+already_AddRefed<nsMIMEInfoBase>
+nsOSHelperAppService::GetFromExtension(const nsCString& aFileExt) {
+  // if the extension is empty, return immediately
+  if (aFileExt.IsEmpty())
+    return nullptr;
+
+  LOG(("Here we do an extension lookup for '%s'\n", aFileExt.get()));
+
+  nsAutoString majorType, minorType,
+               mime_types_description, mailcap_description,
+               handler, mozillaFlags;
+
+  nsresult rv = LookUpTypeAndDescription(NS_ConvertUTF8toUTF16(aFileExt),
+                                         majorType,
+                                         minorType,
+                                         mime_types_description,
+                                         true);
+
+  if (NS_FAILED(rv) || majorType.IsEmpty()) {
+
+#ifdef MOZ_WIDGET_GTK
+    LOG(("Looking in GNOME registry\n"));
+    RefPtr<nsMIMEInfoBase> gnomeInfo =
+      nsGNOMERegistry::GetFromExtension(aFileExt);
+    if (gnomeInfo) {
+      LOG(("Got MIMEInfo from GNOME registry\n"));
+      return gnomeInfo.forget();
+    }
+#endif
+
+    rv = LookUpTypeAndDescription(NS_ConvertUTF8toUTF16(aFileExt),
+                                  majorType,
+                                  minorType,
+                                  mime_types_description,
+                                  false);
+  }
+
+  if (NS_FAILED(rv))
+    return nullptr;
+
+  NS_LossyConvertUTF16toASCII asciiMajorType(majorType);
+  NS_LossyConvertUTF16toASCII asciiMinorType(minorType);
+
+  LOG(("Type/Description results:  majorType='%s', minorType='%s', description='%s'\n",
+          asciiMajorType.get(),
+          asciiMinorType.get(),
+          NS_LossyConvertUTF16toASCII(mime_types_description).get()));
+
+  if (majorType.IsEmpty() && minorType.IsEmpty()) {
+    // we didn't get a type mapping, so we can't do anything useful
+    return nullptr;
+  }
+
+  nsAutoCString mimeType(asciiMajorType + NS_LITERAL_CSTRING("/") + asciiMinorType);
+  RefPtr<nsMIMEInfoUnix> mimeInfo = new nsMIMEInfoUnix(mimeType);
+
+  mimeInfo->AppendExtension(aFileExt);
+  rv = LookUpHandlerAndDescription(majorType, minorType,
+                                   handler, mailcap_description,
+                                   mozillaFlags);
+  LOG(("Handler/Description results:  handler='%s', description='%s', mozillaFlags='%s'\n",
+          NS_LossyConvertUTF16toASCII(handler).get(),
+          NS_LossyConvertUTF16toASCII(mailcap_description).get(),
+          NS_LossyConvertUTF16toASCII(mozillaFlags).get()));
+  mailcap_description.Trim(" \t\"");
+  mozillaFlags.Trim(" \t");
+  if (!mime_types_description.IsEmpty()) {
+    mimeInfo->SetDescription(mime_types_description);
+  } else {
+    mimeInfo->SetDescription(mailcap_description);
+  }
+
+  if (NS_SUCCEEDED(rv) && handler.IsEmpty()) {
+    rv = NS_ERROR_NOT_AVAILABLE;
+  }
+
+  if (NS_SUCCEEDED(rv)) {
+    nsCOMPtr<nsIFile> handlerFile;
+    rv = GetFileTokenForPath(handler.get(), getter_AddRefs(handlerFile));
+
+    if (NS_SUCCEEDED(rv)) {
+      mimeInfo->SetDefaultApplication(handlerFile);
+      mimeInfo->SetPreferredAction(nsIMIMEInfo::useSystemDefault);
+      mimeInfo->SetDefaultDescription(handler);
+    }
+  }
+
+  if (NS_FAILED(rv)) {
+    mimeInfo->SetPreferredAction(nsIMIMEInfo::saveToDisk);
+  }
+
+  return mimeInfo.forget();
+}
+
+already_AddRefed<nsMIMEInfoBase>
+nsOSHelperAppService::GetFromType(const nsCString& aMIMEType) {
+  // if the type is empty, return immediately
+  if (aMIMEType.IsEmpty())
+    return nullptr;
+
+  LOG(("Here we do a mimetype lookup for '%s'\n", aMIMEType.get()));
+
+  // extract the major and minor types
+  NS_ConvertASCIItoUTF16 mimeType(aMIMEType);
+  nsAString::const_iterator start_iter, end_iter,
+                            majorTypeStart, majorTypeEnd,
+                            minorTypeStart, minorTypeEnd;
+
+  mimeType.BeginReading(start_iter);
+  mimeType.EndReading(end_iter);
+
+  // XXX FIXME: add typeOptions parsing in here
+  nsresult rv = ParseMIMEType(start_iter, majorTypeStart, majorTypeEnd,
+                              minorTypeStart, minorTypeEnd, end_iter);
+
+  if (NS_FAILED(rv)) {
+    return nullptr;
+  }
+
+  nsDependentSubstring majorType(majorTypeStart, majorTypeEnd);
+  nsDependentSubstring minorType(minorTypeStart, minorTypeEnd);
+
+  // First check the user's private mailcap file
+  nsAutoString mailcap_description, handler, mozillaFlags;
+  DoLookUpHandlerAndDescription(majorType,
+                                minorType,
+                                handler,
+                                mailcap_description,
+                                mozillaFlags,
+                                true);
+
+  LOG(("Private Handler/Description results:  handler='%s', description='%s'\n",
+          NS_LossyConvertUTF16toASCII(handler).get(),
+          NS_LossyConvertUTF16toASCII(mailcap_description).get()));
+
+  // Now look up our extensions
+  nsAutoString extensions, mime_types_description;
+  LookUpExtensionsAndDescription(majorType,
+                                 minorType,
+                                 extensions,
+                                 mime_types_description);
+
+#ifdef MOZ_WIDGET_GTK
+  if (handler.IsEmpty()) {
+    RefPtr<nsMIMEInfoBase> gnomeInfo = nsGNOMERegistry::GetFromType(aMIMEType);
+    if (gnomeInfo) {
+      LOG(("Got MIMEInfo from GNOME registry without extensions; setting them "
+           "to %s\n", NS_LossyConvertUTF16toASCII(extensions).get()));
+
+      NS_ASSERTION(!gnomeInfo->HasExtensions(), "How'd that happen?");
+      gnomeInfo->SetFileExtensions(NS_ConvertUTF16toUTF8(extensions));
+      return gnomeInfo.forget();
+    }
+  }
+#endif
+
+  if (handler.IsEmpty()) {
+    DoLookUpHandlerAndDescription(majorType,
+                                  minorType,
+                                  handler,
+                                  mailcap_description,
+                                  mozillaFlags,
+                                  false);
+  }
+
+  if (handler.IsEmpty()) {
+    DoLookUpHandlerAndDescription(majorType,
+                                  NS_LITERAL_STRING("*"),
+                                  handler,
+                                  mailcap_description,
+                                  mozillaFlags,
+                                  true);
+  }
+
+  if (handler.IsEmpty()) {
+    DoLookUpHandlerAndDescription(majorType,
+                                  NS_LITERAL_STRING("*"),
+                                  handler,
+                                  mailcap_description,
+                                  mozillaFlags,
+                                  false);
+  }
+
+  LOG(("Handler/Description results:  handler='%s', description='%s', mozillaFlags='%s'\n",
+          NS_LossyConvertUTF16toASCII(handler).get(),
+          NS_LossyConvertUTF16toASCII(mailcap_description).get(),
+          NS_LossyConvertUTF16toASCII(mozillaFlags).get()));
+
+  mailcap_description.Trim(" \t\"");
+  mozillaFlags.Trim(" \t");
+
+  if (handler.IsEmpty() && extensions.IsEmpty() &&
+      mailcap_description.IsEmpty() && mime_types_description.IsEmpty()) {
+    // No real useful info
+    return nullptr;
+  }
+
+  RefPtr<nsMIMEInfoUnix> mimeInfo = new nsMIMEInfoUnix(aMIMEType);
+
+  mimeInfo->SetFileExtensions(NS_ConvertUTF16toUTF8(extensions));
+  if (! mime_types_description.IsEmpty()) {
+    mimeInfo->SetDescription(mime_types_description);
+  } else {
+    mimeInfo->SetDescription(mailcap_description);
+  }
+
+  rv = NS_ERROR_NOT_AVAILABLE;
+  nsCOMPtr<nsIFile> handlerFile;
+  if (!handler.IsEmpty()) {
+    rv = GetFileTokenForPath(handler.get(), getter_AddRefs(handlerFile));
+  }
+
+  if (NS_SUCCEEDED(rv)) {
+    mimeInfo->SetDefaultApplication(handlerFile);
+    mimeInfo->SetPreferredAction(nsIMIMEInfo::useSystemDefault);
+    mimeInfo->SetDefaultDescription(handler);
+  } else {
+    mimeInfo->SetPreferredAction(nsIMIMEInfo::saveToDisk);
+  }
+
+  return mimeInfo.forget();
+}
+
+
+already_AddRefed<nsIMIMEInfo>
+nsOSHelperAppService::GetMIMEInfoFromOS(const nsACString& aType,
+                                        const nsACString& aFileExt,
+                                        bool       *aFound) {
+  *aFound = true;
+  RefPtr<nsMIMEInfoBase> retval = GetFromType(PromiseFlatCString(aType));
+  bool hasDefault = false;
+  if (retval)
+    retval->GetHasDefaultHandler(&hasDefault);
+  if (!retval || !hasDefault) {
+    RefPtr<nsMIMEInfoBase> miByExt = GetFromExtension(PromiseFlatCString(aFileExt));
+    // If we had no extension match, but a type match, use that
+    if (!miByExt && retval)
+      return retval.forget();
+    // If we had an extension match but no type match, set the mimetype and use
+    // it
+    if (!retval && miByExt) {
+      if (!aType.IsEmpty())
+        miByExt->SetMIMEType(aType);
+      miByExt.swap(retval);
+
+      return retval.forget();
+    }
+    // If we got nothing, make a new mimeinfo
+    if (!retval) {
+      *aFound = false;
+      retval = new nsMIMEInfoUnix(aType);
+      if (retval) {
+        if (!aFileExt.IsEmpty())
+          retval->AppendExtension(aFileExt);
+      }
+
+      return retval.forget();
+    }
+
+    // Copy the attributes of retval (mimeinfo from type) onto miByExt, to
+    // return it
+    // but reset to just collected mDefaultAppDescription (from ext)
+    nsAutoString byExtDefault;
+    miByExt->GetDefaultDescription(byExtDefault);
+    retval->SetDefaultDescription(byExtDefault);
+    retval->CopyBasicDataTo(miByExt);
+
+    miByExt.swap(retval);
+  }
+  return retval.forget();
+}
+
+NS_IMETHODIMP
+nsOSHelperAppService::GetProtocolHandlerInfoFromOS(const nsACString &aScheme,
+                                                   bool *found,
+                                                   nsIHandlerInfo **_retval)
+{
+  NS_ASSERTION(!aScheme.IsEmpty(), "No scheme was specified!");
+
+  nsresult rv = OSProtocolHandlerExists(nsPromiseFlatCString(aScheme).get(),
+                                        found);
+  if (NS_FAILED(rv))
+    return rv;
+
+  nsMIMEInfoUnix *handlerInfo =
+    new nsMIMEInfoUnix(aScheme, nsMIMEInfoBase::eProtocolInfo);
+  NS_ENSURE_TRUE(handlerInfo, NS_ERROR_OUT_OF_MEMORY);
+  NS_ADDREF(*_retval = handlerInfo);
+
+  if (!*found) {
+    // Code that calls this requires an object regardless if the OS has
+    // something for us, so we return the empty object.
+    return NS_OK;
+  }
+
+  nsAutoString desc;
+  GetApplicationDescription(aScheme, desc);
+  handlerInfo->SetDefaultDescription(desc);
+
+  return NS_OK;
+}