From bb67f9718411fc9e485d945b8ec13a61f5fec2be Mon Sep 17 00:00:00 2001
From: Jitendra Tripathy <jitendra.kumarx.tripathy@intel.com>
Date: Fri, 24 Jun 2022 09:13:30 +0000
Subject: [PATCH] Fix for PSU2 Power-lost RedFish events

In a dual power supply system, after Removing the PSU2 power
cable/module, power-lost RedFish events are not getting logged in the
RedFish logs. Only SEL entries are getting logged for PSU2. But all the
events are getting logged for PSU1 in the redfish logs.

To get PSU2 events also, replace async_wait instead of async_read_until
while reading the hwmon files.

Tested:
1. The system should have connected with dual PSU's which are drawing
same power.
2. Verified both PSU are connected by executing below ipmitool command.
"ipmitool fru"
3. Removed one of 1600W PSU, which server holding 2 PSU's drawing 1600W.
4. Above step try for both PSU1 and PSU2 by removing and connecting.
5. Verified for both PSU1 and PSU2, eventlogs generated on Redfish
respectively.
Get: https://<BMC-IP>/redfish/v1/Systems/system/LogServices/
             EventLog/Entries

Signed-off-by: Jitendra Tripathy <jitendra.kumarx.tripathy@intel.com>
---
 include/PSUEvent.hpp |  1 -
 src/PSUEvent.cpp     | 42 +++++++++++++++++++++---------------------
 2 files changed, 21 insertions(+), 22 deletions(-)

diff --git a/include/PSUEvent.hpp b/include/PSUEvent.hpp
index 3a39164..72abbae 100644
--- a/include/PSUEvent.hpp
+++ b/include/PSUEvent.hpp
@@ -57,7 +57,6 @@ class PSUSubEvent : public std::enable_shared_from_this<PSUSubEvent>
 
     PowerState readState;
     boost::asio::deadline_timer waitTimer;
-    std::shared_ptr<boost::asio::streambuf> readBuf;
     void restartRead();
     void handleResponse(const boost::system::error_code& err);
     void updateValue(const int& newValue);
diff --git a/src/PSUEvent.cpp b/src/PSUEvent.cpp
index 44275a3..446f14f 100644
--- a/src/PSUEvent.cpp
+++ b/src/PSUEvent.cpp
@@ -157,7 +157,7 @@ PSUSubEvent::PSUSubEvent(
     {
         eventPollMs = static_cast<unsigned int>(pollRate * 1000);
     }
-    fd = open(path.c_str(), O_RDONLY);
+    fd = open(path.c_str(), O_RDONLY | O_NONBLOCK);
     if (fd < 0)
     {
         std::cerr << "PSU sub event failed to open file\n";
@@ -205,20 +205,15 @@ void PSUSubEvent::setupRead(void)
         return;
     }
 
-    std::shared_ptr<boost::asio::streambuf> buffer =
-        std::make_shared<boost::asio::streambuf>();
     std::weak_ptr<PSUSubEvent> weakRef = weak_from_this();
-    boost::asio::async_read_until(
-        inputDev, *buffer, '\n',
-        [weakRef, buffer](const boost::system::error_code& ec,
-                          std::size_t /*bytes_transfered*/) {
-            std::shared_ptr<PSUSubEvent> self = weakRef.lock();
-            if (self)
-            {
-                self->readBuf = buffer;
-                self->handleResponse(ec);
-            }
-        });
+    inputDev.async_wait(boost::asio::posix::descriptor_base::wait_read,
+                        [weakRef](const boost::system::error_code& ec) {
+                            std::shared_ptr<PSUSubEvent> self = weakRef.lock();
+                            if (self)
+                            {
+                                self->handleResponse(ec);
+                            }
+                        });
 }
 
 void PSUSubEvent::restartRead()
@@ -238,23 +233,28 @@ void PSUSubEvent::restartRead()
     });
 }
 
+// Create a buffer expected to be able to hold more characters than will be
+// present in the input file.
+static constexpr uint32_t psuBufLen = 128;
 void PSUSubEvent::handleResponse(const boost::system::error_code& err)
 {
     if ((err == boost::system::errc::bad_file_descriptor) ||
         (err == boost::asio::error::misc_errors::not_found))
     {
+        std::cerr << "Bad file descriptor for " << path << "\n";
         return;
     }
-    std::istream responseStream(readBuf.get());
-    if (!err)
+
+    std::string buffer;
+    buffer.resize(psuBufLen);
+    lseek(fd, 0, SEEK_SET);
+    int rdLen = read(fd, buffer.data(), psuBufLen);
+
+    if (rdLen > 0)
     {
-        std::string response;
         try
         {
-            std::getline(responseStream, response);
-            int nvalue = std::stoi(response);
-            responseStream.clear();
-
+            int nvalue = std::stoi(buffer);
             updateValue(nvalue);
             errCount = 0;
         }
-- 
2.17.1