Add callback ability for URLLoader so an asynchronous proxy can send the

current progress to another process.

Adds a DOWNLOADPROGRESS flag to track download progress to be symetrical with
the upload progress. I implemented the backend of these two flags and made it
refuse to provide progress unless these flags were set.

TEST=none
BUG=none
Review URL: http://codereview.chromium.org/4423001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@65098 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 56 insertions, 11 deletions

diff --git a/ppapi/c/dev/ppb_url_loader_dev.h b/ppapi/c/dev/ppb_url_loader_dev.h
index 44f4dc90..9d63b31 100644
--- a/ppapi/c/dev/ppb_url_loader_dev.h
+++ b/ppapi/c/dev/ppb_url_loader_dev.h
@@ -52,20 +52,27 @@ struct PPB_URLLoader_Dev {
                             struct PP_CompletionCallback callback);
 
   // Returns the current upload progress, which is meaningful after Open has
-  // been called, and the request given to Open must have been configured with
-  // PP_URLREQUESTPROPERTY_REPORTUPLOADPROGRESS set to true.  Progress only
-  // refers to the request body.  This data is only available if the
-  // PP_URLREQUESTPROPERTY_REPORTUPLOADPROGRESS was set to true on the
-  // URLRequestInfo.  This method returns false if upload progress is not
-  // available.
+  // been called. Progress only refers to the request body and does not include
+  // the headers.
+  //
+  // This data is only available if the URLRequestInfo passed to Open() had the
+  // PP_URLREQUESTPROPERTY_REPORTUPLOADPROGRESS flag set to true.
+  //
+  // This method returns false if upload progress is not available.
   bool (*GetUploadProgress)(PP_Resource loader,
                             int64_t* bytes_sent,
                             int64_t* total_bytes_to_be_sent);
 
   // Returns the current download progress, which is meaningful after Open has
-  // been called.  Progress only refers to the response body.  The total bytes
-  // to be received may be unknown, in which case -1 is returned.  This method
-  // returns false if download progress is not available.
+  // been called.  Progress only refers to the response body and does not
+  // include the headers.
+  //
+  // This data is only available if the URLRequestInfo passed to Open() had the
+  // PP_URLREQUESTPROPERTY_REPORTDOWNLOADPROGRESS flag set to true.
+  //
+  // The total bytes to be received may be unknown, in which case
+  // total_bytes_to_be_received will be set to -1. This method returns false if
+  // download progress is not available.
   bool (*GetDownloadProgress)(PP_Resource loader,
                               int64_t* bytes_received,
                               int64_t* total_bytes_to_be_received);
diff --git a/ppapi/c/dev/ppb_url_loader_trusted_dev.h b/ppapi/c/dev/ppb_url_loader_trusted_dev.h
index 4eabe14..84aff0e 100644
--- a/ppapi/c/dev/ppb_url_loader_trusted_dev.h
+++ b/ppapi/c/dev/ppb_url_loader_trusted_dev.h
@@ -5,15 +5,41 @@
 #ifndef PPAPI_C_DEV_PPB_URL_LOADER_TRUSTED_DEV_H_
 #define PPAPI_C_DEV_PPB_URL_LOADER_TRUSTED_DEV_H_
 
+#include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_resource.h"
+#include "ppapi/c/pp_stdint.h"
 
-#define PPB_URLLOADERTRUSTED_DEV_INTERFACE "PPB_URLLoaderTrusted(Dev);0.1"
+#define PPB_URLLOADERTRUSTED_DEV_INTERFACE "PPB_URLLoaderTrusted(Dev);0.2"
+
+// Callback that indicates the status of the download and upload for the
+// given URLLoader resource.
+typedef void (*PP_URLLoaderTrusted_StatusCallback)(
+      PP_Instance pp_instance,
+      PP_Resource pp_resource,
+      int64_t bytes_sent,
+      int64_t total_bytes_to_be_sent,
+      int64_t bytes_received,
+      int64_t total_bytes_to_be_received);
 
 // Available only to trusted implementations.
 struct PPB_URLLoaderTrusted_Dev {
   // Grant this URLLoader the capability to make unrestricted cross-origin
   // requests.
   void (*GrantUniversalAccess)(PP_Resource loader);
+
+  // Registers that the given function will be called when the upload or
+  // downloaded byte count has changed. This is not exposed on the untrusted
+  // interface because it can be quite chatty and encourages people to write
+  // feedback UIs that update as frequently as the progress updates.
+  //
+  // The other serious gotcha with this callback is that the callback must not
+  // mutate the URL loader or cause it to be destroyed.
+  //
+  // However, the proxy layer needs this information to push to the other
+  // process, so we expose it here. Only one callback can be set per URL
+  // Loader. Setting to a NULL callback will disable it.
+  void (*RegisterStatusCallback)(PP_Resource loader,
+                                 PP_URLLoaderTrusted_StatusCallback cb);
 };
 
 #endif  // PPAPI_C_DEV_PPB_URL_LOADER_DEV_H_
diff --git a/ppapi/c/dev/ppb_url_request_info_dev.h b/ppapi/c/dev/ppb_url_request_info_dev.h
index 2503a0c..9916804 100644
--- a/ppapi/c/dev/ppb_url_request_info_dev.h
+++ b/ppapi/c/dev/ppb_url_request_info_dev.h
@@ -18,7 +18,19 @@ typedef enum {
   PP_URLREQUESTPROPERTY_HEADERS,              // string, \n-delim
   PP_URLREQUESTPROPERTY_STREAMTOFILE,         // bool (default=false)
   PP_URLREQUESTPROPERTY_FOLLOWREDIRECTS,      // bool (default=true)
-  PP_URLREQUESTPROPERTY_RECORDUPLOADPROGRESS  // bool (default=false)
+
+  // Set to true if you want to be able to poll the download progress via the
+  // URLLoader.GetDownloadProgress function.
+  //
+  // Boolean (default = false).
+  PP_URLREQUESTPROPERTY_RECORDDOWNLOADPROGRESS,
+
+  // Set to true if you want to be able to pull the upload progress via the
+  // URLLoader.GetUploadProgress function.
+  //
+  // Boolean (default = false).
+  PP_URLREQUESTPROPERTY_RECORDUPLOADPROGRESS
+
   // TODO(darin): Add security/privacy options?
 } PP_URLRequestProperty_Dev;