Allow users to replace allocator and handle OOM everywhere. (#800)

* Adds an indirection to every allocation/deallocation to allow users to 
  plug in ones of their choosing (use custom functions, jemalloc, etc).

* Gracefully handle OOM everywhere in hiredis.  This should make it possible
  for users of the library to have more flexibility in how they handle such situations.

* Changes `redisReaderTask->elements` from an `int` to a `long long` to prevent
  a possible overflow when transferring the task elements into a `redisReply`.

* Adds a configurable `max elements` member to `redisReader` that defaults to
  2^32 - 1.  This can be set to "unlimited" by setting the value to zero.

1 files changed, 10 insertions, 0 deletions

diff --git a/README.md b/README.md
index a979110..4e7b228 100644
--- a/README.md
+++ b/README.md
@@ -404,6 +404,16 @@ This should be done only in order to maximize performances when working with
 large payloads. The context should be set back to `REDIS_READER_MAX_BUF` again
 as soon as possible in order to prevent allocation of useless memory.
 
+### Reader max array elements
+
+By default the hiredis reply parser sets the maximum number of multi-bulk elements
+to 2^32 - 1 or 4,294,967,295 entries.  If you need to process multi-bulk replies
+with more than this many elements you can set the value higher or to zero, meaning
+unlimited with:
+```c
+context->reader->maxelements = 0;
+```
+
 ## SSL/TLS Support
 
 ### Building