issue-411: This commit adds additional logging to the cpu profiler to warn when the profiler is run and no CPUPROFILE environment setting can be found. It also adds a new environment variable PERFTOOLS_UNITTEST to allow certain modules to take action when running under the umbrella of a unit test.

git-svn-id: http://gperftools.googlecode.com/svn/trunk@162 6b5cf1ce-ec42-a296-1ba9-69fdba395a50

2 files changed, 27 insertions, 6 deletions

diff --git a/src/profiler.cc b/src/profiler.cc
index dfb6aab..3272fa4 100644
--- a/src/profiler.cc
+++ b/src/profiler.cc
@@ -70,6 +70,12 @@ typedef int ucontext_t;   // just to quiet the compiler, mostly
 
 using std::string;
 
+DEFINE_bool(cpu_profile_unittest,
+            EnvToBool("PERFTOOLS_UNITTEST", true),
+            "Determines whether or not we are running under the \
+             control of a unit test. This allows us to include or \
+			 exclude certain behaviours.");
+
 // Collects up all profile data.  This is a singleton, which is
 // initialized by a constructor at startup.
 class CpuProfiler {
@@ -139,12 +145,19 @@ CpuProfiler::CpuProfiler()
   // is no need to limit the number of profilers.
   char fname[PATH_MAX];
   if (!GetUniquePathFromEnv("CPUPROFILE", fname)) {
+    if (!FLAGS_cpu_profile_unittest) {
+      RAW_LOG(WARNING, "CPU profiler linked but no valid CPUPROFILE environment variable found\n");
+    }
     return;
   }
   // We don't enable profiling if setuid -- it's a security risk
 #ifdef HAVE_GETEUID
-  if (getuid() != geteuid())
+  if (getuid() != geteuid()) {
+    if (!FLAGS_cpu_profile_unittest) {
+      RAW_LOG(WARNING, "Cannot perform CPU profiling when running with setuid\n");
+    }
     return;
+  }
 #endif
 
   if (!Start(fname, NULL)) {
diff --git a/src/tests/profiler_unittest.sh b/src/tests/profiler_unittest.sh
index 4668fa7..4085f2c 100755
--- a/src/tests/profiler_unittest.sh
+++ b/src/tests/profiler_unittest.sh
@@ -85,6 +85,14 @@ PROFILER4_REALNAME=`Realname "$PROFILER4"`
 # It's meaningful to the profiler, so make sure we know its state
 unset CPUPROFILE
 
+# Some output/logging in the profiler can cause issues when running the unit
+# tests. For example, logging a warning when the profiler is detected as being
+# present but no CPUPROFILE is specified in the environment. Especially when
+# we are checking for a silent run or specific timing constraints are being
+# checked. So set the env variable signifying that we are running in a unit
+# test environment.
+PERFTOOLS_UNITTEST=1 
+
 rm -rf "$TMPDIR"
 mkdir "$TMPDIR" || exit 2
 
@@ -95,11 +103,11 @@ RegisterFailure() {
 }
 
 # Takes two filenames representing profiles, with their executable scripts,
-# and a multiplier, and verifies that the 'contentful' functions in
-# each profile take the same time (possibly scaled by the given
-# multiplier).  It used to be "same" meant within 50%, after adding an 
-# noise-reducing X units to each value.  But even that would often
-# spuriously fail, so now it's "both non-zero".  We're pretty forgiving.
+# and a multiplier, and verifies that the 'contentful' functions in each
+# profile take the same time (possibly scaled by the given multiplier). It
+# used to be "same" meant within 50%, after adding an noise-reducing X units
+# to each value.  But even that would often spuriously fail, so now it's
+# "both non-zero". We're pretty forgiving.
 VerifySimilar() {
   prof1="$TMPDIR/$1"
   exec1="$2"