require 'set'

LIBRUBY_SO = 'libruby.so'

PROBES_D = 'probes.d'

###

# Detect SystemTap section headers presence.

stap_headers = [

  '\.stapsdt\.base',

  '\.note\.stapsdt'

]

header_regexp = %r{ (#{stap_headers.join('|')}) }

section_headers = `readelf -S "#{LIBRUBY_SO}"`

detected_stap_headers = section_headers.scan(header_regexp).flatten

# Assume there are both headers until this is proven wrong ;)

unless detected_stap_headers.size == 2

  puts 'ERROR: SystemTap (DTrace) headers were not detected in resulting library.'

  exit false

end

###

# Find if every declared probe is propagated to resulting library.

# Colect probes specified in probes.d file.

probes = []

File.open(PROBES_D) do |file|

  file.each_line do |line|

    if probe = line[/probe (\S+)\(.*\);/, 1]

      probes << probe

    end

  end

end

probes = Set.new probes

# These probes are excluded by VM_COLLECT_USAGE_DETAILS ifdef.

EXCLUDE_PROBES = Set.new %w(insn insn__operand)

unless EXCLUDE_PROBES.subset? probes

  puts 'ERROR: Change in SystemTap (DTrace) probes definition file detected.'

  exit false

end

probes -= EXCLUDE_PROBES

# Detect probes in resulting library.

probe_regexp = %r{

^\s*stapsdt\s*0[xX][0-9a-fA-F]+\tNT_STAPSDT \(SystemTap probe descriptors\)$

^\s*Provider: ruby$

^\s*Name: (\S+)$

}

notes = `readelf -n "#{LIBRUBY_SO}"`

detected_probes = Set.new notes.scan(probe_regexp).flatten

# Both sets must be equal, otherwise something is wrong.

unless probes == detected_probes

  puts 'ERROR: SystemTap (DTrace) probes were not correctly propagated into resulting library.'

  exit false

end