Big comment and naming cleanup. Ready for prime-time.

Add to-do list to _httpinternal.h to guide anyone who
wants to pitch in and help.

1 files changed, 73 insertions, 20 deletions

diff --git a/indra/llcorehttp/_httpinternal.h b/indra/llcorehttp/_httpinternal.h
index 97ec5ee1d6..465e2036b3 100644
--- a/indra/llcorehttp/_httpinternal.h
+++ b/indra/llcorehttp/_httpinternal.h
@@ -32,12 +32,65 @@
 // something wrong is probably happening.
 
 
+// --------------------------------------------------------------------
+// General library to-do list
+//
+// - Implement policy classes.  Structure is mostly there just didn't
+//   need it for the first consumer.
+// - Consider Removing 'priority' from the request interface.  Its use
+//   in an always active class can lead to starvation of low-priority
+//   requests.  Requires coodination of priority values across all
+//   components that share a class.  Changing priority across threads
+//   is slightly expensive (relative to gain) and hasn't been completely
+//   implemented.  And the major user of priority, texture fetches,
+//   may not really need it.
+// - Set/get for global policy and policy classes is clumsy.  Rework
+//   it heading in a direction that allows for more dynamic behavior.
+// - Move HttpOpRequest::prepareRequest() to HttpLibcurl for the
+//   pedantic.
+// - Update downloader and other long-duration services are going to
+//   need a progress notification.  Initial idea is to introduce a
+//   'repeating request' which can piggyback on another request and
+//   persist until canceled or carrier completes.  Current queue
+//   structures allow an HttpOperation object to be enqueued
+//   repeatedly, so...
+// - Investigate making c-ares' re-implementation of a resolver library
+//   more resilient or more intelligent on Mac.  Part of the DNS failure
+//   lies in here.  The mechanism also looks a little less dynamic
+//   than needed in an environments where networking is changing.
+// - Global optimizations:  'borrowing' connections from other classes,
+//   HTTP pipelining.
+// - Dynamic/control system stuff:  detect problems and self-adjust.
+//   This won't help in the face of the router problems we've looked
+//   at, however.  Detect starvation due to UDP activity and provide
+//   feedback to it.
+//
+// Integration to-do list
+// - LLTextureFetch still needs a major refactor.  The use of
+//   LLQueuedThread makes it hard to inspect workers and do the
+//   resource waiting we're now doing.  Rebuild along simpler lines
+//   some of which are suggested in new commentary at the top of
+//   the main source file.
+// - Expand areas of usage eventually leading to the removal of LLCurl.
+//   Rough order of expansion:
+//   .  Mesh fetch
+//   .  Avatar names
+//   .  Group membership lists
+//   .  Caps access in general
+//   .  'The rest'
+// - Adapt texture cache, image decode and other image consumers to
+//   the BufferArray model to reduce data copying.  Alternatively,
+//   adapt this library to something else.
+//
+// --------------------------------------------------------------------
+
+
 // If '1', internal ready queues will not order ready
 // requests by priority, instead it's first-come-first-served.
 // Reprioritization requests have the side-effect of then
 // putting the modified request at the back of the ready queue.
 
-#define	LLCORE_READY_QUEUE_IGNORES_PRIORITY		1
+#define	LLCORE_HTTP_READY_QUEUE_IGNORES_PRIORITY		1
 
 
 namespace LLCore
@@ -45,48 +98,48 @@ namespace LLCore
 
 // Maxium number of policy classes that can be defined.
 // *TODO:  Currently limited to the default class, extend.
-const int POLICY_CLASS_LIMIT = 1;
+const int HTTP_POLICY_CLASS_LIMIT = 1;
 
 // Debug/informational tracing.  Used both
 // as a global option and in per-request traces.
-const int TRACE_OFF = 0;
-const int TRACE_LOW = 1;
-const int TRACE_CURL_HEADERS = 2;
-const int TRACE_CURL_BODIES = 3;
+const int HTTP_TRACE_OFF = 0;
+const int HTTP_TRACE_LOW = 1;
+const int HTTP_TRACE_CURL_HEADERS = 2;
+const int HTTP_TRACE_CURL_BODIES = 3;
 
-const int TRACE_MIN = TRACE_OFF;
-const int TRACE_MAX = TRACE_CURL_BODIES;
+const int HTTP_TRACE_MIN = HTTP_TRACE_OFF;
+const int HTTP_TRACE_MAX = HTTP_TRACE_CURL_BODIES;
 
 // Request retry limits
-const int DEFAULT_RETRY_COUNT = 5;
-const int LIMIT_RETRY_MIN = 0;
-const int LIMIT_RETRY_MAX = 100;
+const int HTTP_RETRY_COUNT_DEFAULT = 5;
+const int HTTP_RETRY_COUNT_MIN = 0;
+const int HTTP_RETRY_COUNT_MAX = 100;
 
-const int DEFAULT_HTTP_REDIRECTS = 10;
+const int HTTP_REDIRECTS_DEFAULT = 10;
 
 // Timeout value used for both connect and protocol exchange.
 // Retries and time-on-queue are not included and aren't
 // accounted for.
-const long DEFAULT_TIMEOUT = 30L;
-const long LIMIT_TIMEOUT_MIN = 0L;
-const long LIMIT_TIMEOUT_MAX = 3600L;
+const long HTTP_REQUEST_TIMEOUT_DEFAULT = 30L;
+const long HTTP_REQUEST_TIMEOUT_MIN = 0L;
+const long HTTP_REQUEST_TIMEOUT_MAX = 3600L;
 
 // Limits on connection counts
-const int DEFAULT_CONNECTIONS = 8;
-const int LIMIT_CONNECTIONS_MIN = 1;
-const int LIMIT_CONNECTIONS_MAX = 256;
+const int HTTP_CONNECTION_LIMIT_DEFAULT = 8;
+const int HTTP_CONNECTION_LIMIT_MIN = 1;
+const int HTTP_CONNECTION_LIMIT_MAX = 256;
 
 // Tuning parameters
 
 // Time worker thread sleeps after a pass through the
 // request, ready and active queues.
-const int LOOP_SLEEP_NORMAL_MS = 2;
+const int HTTP_SERVICE_LOOP_SLEEP_NORMAL_MS = 2;
 
 // Block allocation size (a tuning parameter) is found
 // in bufferarray.h.
 
 // Compatibility controls
-const bool ENABLE_LINKSYS_WRT54G_V5_DNS_FIX = true;
+const bool HTTP_ENABLE_LINKSYS_WRT54G_V5_DNS_FIX = true;
 
 }  // end namespace LLCore