Merge pull request #126 from benbuckman/benbuckman-max-interval

ArgumentError on interval <1 or >1m

Author: tmm1

ext/stackprof/stackprof.c

@@ -16,6 +16,7 @@
 #include <pthread.h>
 
 #define BUF_SIZE 2048
+#define MICROSECONDS_IN_SECOND 1000000
 
 #define FAKE_FRAME_GC    INT2FIX(0)
 #define FAKE_FRAME_MARK  INT2FIX(1)
@@ -120,6 +121,10 @@ stackprof_start(int argc, VALUE *argv, VALUE self)
     }
     if (!RTEST(mode)) mode = sym_wall;
 
+    if (!NIL_P(interval) && (NUM2INT(interval) < 1 || NUM2INT(interval) >= MICROSECONDS_IN_SECOND)) {
+        rb_raise(rb_eArgError, "interval is a number of microseconds between 1 and 1 million");
+    }
+
     if (!_stackprof.frames) {
 	_stackprof.frames = st_init_numtable();
 	_stackprof.overall_signals = 0;

test/test_stackprof.rb

@@ -232,6 +232,15 @@ def test_pathname_out
     refute_empty profile[:frames]
   end
 
+  def test_min_max_interval
+    [-1, 0, 1_000_000, 1_000_001].each do |invalid_interval|
+      err = assert_raises(ArgumentError, "invalid interval #{invalid_interval}") do
+        StackProf.run(interval: invalid_interval, debug: true) {}
+      end
+      assert_match(/microseconds/, err.message)
+    end
+  end
+
   def math
     250_000.times do
       2 ** 10