sync_manager: Create sync watch class

Create a watch class to monitor the files and directories
specified in the synclist file.
Store the file descriptors and file names in a map to be
able to know the full path of the file that triggered the
event. The watch descriptor number does not change so it
can be a single variable.

Change-Id: I211225ddc012af85d9be39ae5d40b8258d73435d
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/sync_watch.cpp b/sync_watch.cpp
new file mode 100644
index 0000000..0fc61d8
--- /dev/null
+++ b/sync_watch.cpp
@@ -0,0 +1,89 @@
+#include <experimental/filesystem>
+#include <fstream>
+#include <phosphor-logging/log.hpp>
+#include <sys/inotify.h>
+#include <unistd.h>
+#include "config.h"
+#include "sync_watch.hpp"
+
+namespace phosphor
+{
+namespace software
+{
+namespace manager
+{
+
+using namespace phosphor::logging;
+namespace fs = std::experimental::filesystem;
+
+SyncWatch::SyncWatch(sd_event& loop,
+                     std::function<int(fs::path&)> syncCallback) :
+    syncCallback(syncCallback)
+{
+    auto syncfile = fs::path(SYNC_LIST_DIR_PATH) / SYNC_LIST_FILE_NAME;
+    if (fs::exists(syncfile))
+    {
+        std::string line;
+        std::ifstream file(syncfile.c_str());
+        while (std::getline(file, line))
+        {
+            auto fd = inotify_init1(IN_NONBLOCK);
+            if (-1 == fd)
+            {
+                log<level::ERR>("inotify_init1 failed",
+                                entry("ERRNO=%d", errno),
+                                entry("FILENAME=%s", line.c_str()),
+                                entry("SYNCFILE=%s", syncfile.c_str()));
+                continue;
+            }
+
+            auto wd = inotify_add_watch(fd, line.c_str(), IN_CLOSE_WRITE);
+            if (-1 == wd)
+            {
+                log<level::ERR>("inotify_add_watch failed",
+                                entry("ERRNO=%d", errno),
+                                entry("FILENAME=%s", line.c_str()),
+                                entry("SYNCFILE=%s", syncfile.c_str()));
+                close(fd);
+                continue;
+            }
+
+            auto rc =
+                sd_event_add_io(&loop, nullptr, fd, EPOLLIN, callback, this);
+            if (0 > rc)
+            {
+                log<level::ERR>("failed to add to event loop",
+                                entry("RC=%d", rc),
+                                entry("FILENAME=%s", line.c_str()),
+                                entry("SYNCFILE=%s", syncfile.c_str()));
+                inotify_rm_watch(fd, wd);
+                close(fd);
+                continue;
+            }
+
+            fileMap[fd].insert(std::make_pair(wd, fs::path(line)));
+        }
+    }
+}
+
+SyncWatch::~SyncWatch()
+{
+    for (const auto& fd : fileMap)
+    {
+        for (const auto& wd : fd.second)
+        {
+            inotify_rm_watch(fd.first, wd.first);
+        }
+        close(fd.first);
+    }
+}
+
+int SyncWatch::callback(sd_event_source* s, int fd, uint32_t revents,
+                        void* userdata)
+{
+    return 0;
+}
+
+} // namespace manager
+} // namespace software
+} // namespace phosphor