config: allow {get,set}_val on subsystem debug levels

This mimics the allows you to get and set subsystem debug levels via the
normal config access methods.  Among other things, this allows librados
users to set debug levels.

Fixes: #2350
Signed-off-by: Sage Weil <sage.weil@dreamhost.com>

2 files changed, 37 insertions, 3 deletions

diff --git a/src/common/config.cc b/src/common/config.cc
index b904a8973e2..870b8bf977c 100644
--- a/src/common/config.cc
+++ b/src/common/config.cc
@@ -591,6 +591,26 @@ int md_config_t::set_val(const char *key, const char *val)
 
   string k(ConfFile::normalize_key_name(key));
 
+  // subsystems?
+  if (strncmp(k.c_str(), "debug_", 6) == 0) {
+    for (int o = 0; o < subsys.get_num(); o++) {
+      std::string as_option = "debug_" + subsys.get_name(o);
+      if (k == as_option) {
+	int log, gather;
+	int r = sscanf(v.c_str(), "%d/%d", &log, &gather);
+	if (r >= 1) {
+	  if (r < 2)
+	    gather = log;
+	  //	  cout << "subsys " << subsys.get_name(o) << " log " << log << " gather " << gather << std::endl;
+	  subsys.set_log_level(o, log);
+	  subsys.set_gather_level(o, gather);
+	  return 0;
+	}
+	return -EINVAL;
+      }
+    }	
+  }
+
   for (int i = 0; i < NUM_CONFIG_OPTIONS; ++i) {
     config_option *opt = &config_optionsp[i];
     if (strcmp(opt->name, k.c_str()) == 0) {
@@ -681,6 +701,20 @@ int md_config_t::_get_val(const char *key, char **buf, int len) const
     snprintf(*buf, len, "%s", str.c_str());
     return (l > len) ? -ENAMETOOLONG : 0;
   }
+
+  // subsys?
+  for (int o = 0; o < subsys.get_num(); o++) {
+    std::string as_option = "debug_" + subsys.get_name(o);
+    if (k == as_option) {
+      if (len == -1) {
+	*buf = (char*)malloc(20);
+	len = 20;
+      }
+      int l = snprintf(*buf, len, "%d/%d", subsys.get_log_level(o), subsys.get_gather_level(o));
+      return (l == len) ? -ENAMETOOLONG : 0;
+    }
+  }
+
   // couldn't find a configuration option with key 'k'
   return -ENOENT;
 }
diff --git a/src/log/SubsystemMap.h b/src/log/SubsystemMap.h
index af1430dca0c..31233e0e1c6 100644
--- a/src/log/SubsystemMap.h
+++ b/src/log/SubsystemMap.h
@@ -52,19 +52,19 @@ public:
     m_subsys[subsys].gather_level = gather;
   }
 
-  int get_log_level(unsigned subsys) {
+  int get_log_level(unsigned subsys) const {
     if (subsys >= m_subsys.size())
       subsys = 0;
     return m_subsys[subsys].log_level;
   }
 
-  int get_gather_level(unsigned subsys) {
+  int get_gather_level(unsigned subsys) const {
     if (subsys >= m_subsys.size())
       subsys = 0;
     return m_subsys[subsys].gather_level;
   }
 
-  const string& get_name(unsigned subsys) {
+  const string& get_name(unsigned subsys) const {
     if (subsys >= m_subsys.size())
       subsys = 0;
     return m_subsys[subsys].name;