Bug 785124 - Pt 3 - Modify the updater to support update.link file. r=rstrong

From 76c70c31f5362f7c91d567ca04329195d8126f26 Mon Sep 17 00:00:00 2001
 file. Prefer sdcard for download
---
 toolkit/mozapps/update/updater/updater.cpp |   53 +++++++++++++++++++++++++---
 toolkit/xre/nsUpdateDriver.cpp             |   13 +++++--
 2 files changed, 60 insertions(+), 6 deletions(-)

toolkit/mozapps/update/updater/updater.cpp

@@ -2085,6 +2085,50 @@ ReadMARChannelIDs(const NS_tchar *path, MARChannelStringTable *results)
 }
 #endif
 
+static int
+GetUpdateFileName(NS_tchar *fileName, int maxChars)
+{
+#if defined(MOZ_WIDGET_GONK)
+  // If an update.link file exists, then it will contain the name
+  // of the update file (terminated by a newline).
+
+  NS_tchar linkFileName[MAXPATHLEN];
+  NS_tsnprintf(linkFileName, sizeof(linkFileName)/sizeof(linkFileName[0]),
+               NS_T("%s/update.link"), gSourcePath);
+  AutoFile linkFile = NS_tfopen(linkFileName, NS_T("rb"));
+  if (linkFile == NULL) {
+    NS_tsnprintf(fileName, maxChars,
+                 NS_T("%s/update.mar"), gSourcePath);
+    return OK;
+  }
+
+  char dataFileName[MAXPATHLEN];
+  size_t bytesRead;
+
+  if ((bytesRead = fread(dataFileName, 1, sizeof(dataFileName)-1, linkFile)) <= 0) {
+    *fileName = NS_T('\0');
+    return READ_ERROR;
+  }
+  if (dataFileName[bytesRead-1] == '\n') {
+    // Strip trailing newline (for \n and \r\n)
+    bytesRead--;
+  }
+  if (dataFileName[bytesRead-1] == '\r') {
+    // Strip trailing CR (for \r, \r\n)
+    bytesRead--;
+  }
+  dataFileName[bytesRead] = '\0';
+
+  strncpy(fileName, dataFileName, maxChars-1);
+  fileName[maxChars-1] = '\0';
+#else
+  // We currently only support update.link files under GONK
+  NS_tsnprintf(fileName, maxChars,
+               NS_T("%s/update.mar"), gSourcePath);
+#endif
+  return OK;
+}
+
 static void
 UpdateThreadFunc(void *param)
 {
@@ -2094,10 +2138,10 @@ UpdateThreadFunc(void *param)
     rv = ProcessReplaceRequest();
   } else {
     NS_tchar dataFile[MAXPATHLEN];
-    NS_tsnprintf(dataFile, sizeof(dataFile)/sizeof(dataFile[0]),
-                 NS_T("%s/update.mar"), gSourcePath);
-
-    rv = gArchiveReader.Open(dataFile);
+    rv = GetUpdateFileName(dataFile, sizeof(dataFile)/sizeof(dataFile[0]));
+    if (rv == OK) {
+      rv = gArchiveReader.Open(dataFile);
+    }
 
 #ifdef MOZ_VERIFY_MAR_SIGNATURE
     if (rv == OK) {

toolkit/xre/nsUpdateDriver.cpp

@@ -987,8 +987,17 @@ nsUpdateProcessor::ProcessUpdate(nsIUpdate* aUpdate)
   if (dirProvider) { // Normal code path
     // Check for and process any available updates
     bool persistent;
-    nsresult rv = dirProvider->GetFile(XRE_UPDATE_ROOT_DIR, &persistent,
-                                       getter_AddRefs(updRoot));
+    nsresult rv = NS_ERROR_FAILURE; // Take the NS_FAILED path when non-GONK
+#ifdef MOZ_WIDGET_GONK
+    // Check in the sdcard for updates first, since that's our preferred
+    // download location.
+    rv = dirProvider->GetFile(XRE_UPDATE_ARCHIVE_DIR, &persistent,
+                              getter_AddRefs(updRoot));
+#endif
+    if (NS_FAILED(rv)) {
+      rv = dirProvider->GetFile(XRE_UPDATE_ROOT_DIR, &persistent,
+                                getter_AddRefs(updRoot));
+    }
     // XRE_UPDATE_ROOT_DIR may fail. Fallback to appDir if failed
     if (NS_FAILED(rv))
       updRoot = dirProvider->GetAppDir();

xpcom/build/nsXULAppAPI.h

@@ -123,6 +123,14 @@
  */
 #define XRE_UPDATE_ROOT_DIR "UpdRootD"
 
+/**
+ * A directory service key which provides an alternate location 
+ * to UpdRootD to  to store large files. This key is currently 
+ * only implemented in the Gonk directory service provider. 
+ */
+
+#define XRE_UPDATE_ARCHIVE_DIR "UpdArchD"
+
 /**
  * A directory service key which provides the directory where an OS update is
 *  applied.