Add unicode bitehist!

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    rbbcc (0.1.1)
+    rbbcc (0.2.0)
 
 GEM
   remote: https://rubygems.org/

examples/charty/Gemfile

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+source "https://rubygems.org"
+
+git_source(:github) {|repo_name| "https://github.com/#{repo_name}" }
+
+gem "rbbcc", path: '../../'
+gem "charty", path: '/usr/local/ghq/github.com/udzura/charty'
+gem "unicode_plot"
+gem "numo"

examples/charty/Gemfile.lock

@@ -0,0 +1,44 @@
+PATH
+  remote: ../..
+  specs:
+    rbbcc (0.2.0)
+
+PATH
+  remote: /usr/local/ghq/github.com/udzura/charty
+  specs:
+    charty (0.2.2)
+      red-colors
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    enumerable-statistics (2.0.1)
+    numo (0.1.1)
+      numo-fftw (~> 0.1.1)
+      numo-gnuplot (~> 0.2.4)
+      numo-gsl (~> 0.1.1)
+      numo-linalg (~> 0.1.0)
+      numo-narray (~> 0.9.1)
+    numo-fftw (0.1.1)
+      numo-narray (~> 0.9.0)
+    numo-gnuplot (0.2.4)
+    numo-gsl (0.1.2)
+      numo-narray (>= 0.9.0.8)
+    numo-linalg (0.1.5)
+      numo-narray (>= 0.9.1.4)
+    numo-narray (0.9.1.6)
+    red-colors (0.1.1)
+    unicode_plot (0.0.4)
+      enumerable-statistics (>= 2.0.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  charty!
+  numo
+  rbbcc!
+  unicode_plot
+
+BUNDLED WITH
+   2.0.2

examples/charty/bitehist-unicode.rb

@@ -0,0 +1,87 @@
+#!/usr/bin/env ruby
+#
+# bitehist.rb, ported from bitehist.py. See license on that file
+#
+# Written as a basic example of using histograms to show a distribution.
+#
+# A Ctrl-C will print the gathered histogram then exit.
+#
+
+require 'rbbcc'
+include RbBCC
+
+b = BCC.new(text: <<CLANG)
+#include <uapi/linux/ptrace.h>
+#include <linux/blkdev.h>
+
+BPF_HISTOGRAM(dist);
+BPF_HISTOGRAM(dist_linear);
+
+int kprobe__blk_account_io_completion(struct pt_regs *ctx, struct request *req)
+{
+  dist.increment(bpf_log2l(req->__data_len / 1024));
+  dist_linear.increment(req->__data_len / 1024);
+  return 0;
+}
+CLANG
+
+puts "Tracing... Hit Ctrl-C to end."
+
+loop do
+  begin
+    sleep 0.1
+  rescue Interrupt
+    puts
+    break
+  end
+end
+
+require 'unicode_plot'
+def log2hist_unicode(table)
+  strip_leading_zero = true
+  vals = Array.new($log2_index_max) { 0 }
+  data = {}
+  table.each_pair do |k, v|
+    vals[k.to_bcc_value] = v.to_bcc_value
+  end
+
+  log2_dist_max = 64
+  idx_max = -1
+  val_max = 0
+
+  vals.each_with_index do |v, i|
+    idx_max = i if v > 0
+    val_max = v if v > val_max
+  end
+
+  (1...(idx_max + 1)).each do |i|
+    low = (1 << i) >> 1
+    high = (1 << i)
+    if (low == high)
+      low -= 1
+    end
+    val = vals[i]
+
+    if strip_leading_zero
+      if val
+        data["[#{low}, #{high})"] = val
+        strip_leading_zero = false
+      end
+    else
+      data["[#{low}, #{high})"] = val
+    end
+  end
+
+  unless data.empty?
+    puts UnicodePlot.barplot(data: data, title: "log2 histogram").render
+  else
+    puts "No sample found."
+  end
+end
+
+log2hist_unicode b["dist"]
+
+# puts
+# puts "linear histogram"
+# puts "~~~~~~~~~~~~~~~~"
+# b["dist_linear"].print_linear_hist("kbytes")