Improve the TSMgmtUpdateRegister with an optional file name

doc/developer-guide/api/functions/TSMgmtUpdateRegister.en.rst

@@ -28,7 +28,7 @@ Synopsis
 
     #include <ts/ts.h>
 
-.. function:: void TSMgmtUpdateRegister(TSCont contp, const char * plugin_name)
+.. function:: void TSMgmtUpdateRegister(TSCont contp, const char *plugin_name, const char *plugin_file_name=nullptr)
 
 Description
 ===========

include/api/InkAPIInternal.h

@@ -37,6 +37,7 @@
 #include "api/APIHooks.h"
 #include "api/FeatureAPIHooks.h"
 
+#include "swoc/swoc_file.h"
 #include "ts/InkAPIPrivateIOCore.h"
 #include "ts/experimental.h"
 
@@ -143,12 +144,12 @@ class ConfigUpdateCbTable
   ConfigUpdateCbTable();
   ~ConfigUpdateCbTable();
 
-  void insert(INKContInternal *contp, const char *name);
-  void invoke(const char *name);
+  void insert(INKContInternal *contp, const char *name, const char *file_name = nullptr);
+  void invoke();
   void invoke(INKContInternal *contp);
 
 private:
-  std::unordered_map<std::string, INKContInternal *> cb_table;
+  std::unordered_map<std::string, std::tuple<INKContInternal *, swoc::file::path, swoc::file::file_time_type>> cb_table;
 };
 
 #include "HttpAPIHooks.h"

include/ts/ts.h

@@ -1255,7 +1255,7 @@ namespace c
 
   /* --------------------------------------------------------------------------
      Management */
-  void TSMgmtUpdateRegister(TSCont contp, const char *plugin_name);
+  void TSMgmtUpdateRegister(TSCont contp, const char *plugin_name, const char *plugin_file_name = nullptr);
   TSReturnCode TSMgmtIntGet(const char *var_name, TSMgmtInt *result);
   TSReturnCode TSMgmtCounterGet(const char *var_name, TSMgmtCounter *result);
   TSReturnCode TSMgmtFloatGet(const char *var_name, TSMgmtFloat *result);

src/api/ConfigUpdateCbTable.cc

@@ -28,31 +28,46 @@ ConfigUpdateCbTable::ConfigUpdateCbTable() {}
 ConfigUpdateCbTable::~ConfigUpdateCbTable() {}
 
 void
-ConfigUpdateCbTable::insert(INKContInternal *contp, const char *name)
+ConfigUpdateCbTable::insert(INKContInternal *contp, const char *name, const char *file_name)
 {
-  if (contp && name) {
-    cb_table.emplace(name, contp);
+  ink_assert(contp != nullptr);
+  ink_assert(name != nullptr);
+
+  if (nullptr != file_name) {
+    swoc::file::path file_path{file_name};
+    std::error_code ec;
+    auto timestamp = swoc::file::last_write_time(file_path, ec);
+
+    if (!ec) {
+      cb_table.emplace(name, std::make_tuple(contp, file_path, timestamp));
+    } else {
+      Error("Failed to stat %s: %s", file_path.c_str(), ec.message().c_str());
+    }
+  } else {
+    cb_table.emplace(name, std::make_tuple(contp, swoc::file::path{}, swoc::file::file_time_type{}));
   }
 }
 
 void
-ConfigUpdateCbTable::invoke(const char *name)
+ConfigUpdateCbTable::invoke()
 {
-  INKContInternal *contp;
+  for (auto &&it : cb_table) {
+    auto &[contp, file_path, timestamp] = it.second;
+
+    if (!file_path.empty()) {
+      std::error_code ec;
+      auto newtime = swoc::file::last_write_time(file_path, ec);
 
-  if (name != nullptr) {
-    if (strcmp(name, "*") == 0) {
-      for (auto &&it : cb_table) {
-        contp = it.second;
-        ink_assert(contp != nullptr);
-        invoke(contp);
+      if (!ec) {
+        if (newtime > timestamp) {
+          timestamp = newtime;
+          invoke(contp);
+        }
+      } else {
+        Error("Failed to stat %s: %s", file_path.c_str(), ec.message().c_str());
       }
     } else {
-      if (auto it = cb_table.find(name); it != cb_table.end()) {
-        contp = it->second;
-        ink_assert(contp != nullptr);
-        invoke(contp);
-      }
+      invoke(contp);
     }
   }
 }

src/api/InkAPI.cc

@@ -4096,12 +4096,12 @@ tsapi::c::TSConfigDataGet(TSConfig configp)
 ////////////////////////////////////////////////////////////////////
 
 void
-tsapi::c::TSMgmtUpdateRegister(TSCont contp, const char *plugin_name)
+tsapi::c::TSMgmtUpdateRegister(TSCont contp, const char *plugin_name, const char *plugin_file_name)
 {
   sdk_assert(sdk_sanity_check_iocore_structure(contp) == TS_SUCCESS);
   sdk_assert(sdk_sanity_check_null_ptr((void *)plugin_name) == TS_SUCCESS);
 
-  global_config_cbs->insert((INKContInternal *)contp, plugin_name);
+  global_config_cbs->insert((INKContInternal *)contp, plugin_name, plugin_file_name);
 }
 
 TSReturnCode

src/mgmt/config/FileManager.cc

@@ -193,9 +193,8 @@ void
 FileManager::invokeConfigPluginCallbacks()
 {
   Debug("filemanager", "invoke plugin callbacks");
-  static const std::string_view s{"*"};
   if (_pluginCallbackList) {
-    _pluginCallbackList->invoke(s.data());
+    _pluginCallbackList->invoke();
   }
 }