Module: PyCall::LibPython::Finder

Defined in:
lib/pycall/libpython/finder.rb

Constant Summary collapse

LIBPREFIX =
libprefix || 'lib'
LIBSUFFIX =
libsuffix || 'so'
DEFAULT_PYTHON =
[
  -'python3',
  -'python',
].freeze

Class Method Summary collapse

Class Method Details

.find_libpython(python = nil) ⇒ Object



39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
# File 'lib/pycall/libpython/finder.rb', line 39

def find_libpython(python = nil)
  debug_report("find_libpython(#{python.inspect})")
  python, python_config = find_python_config(python)

  # Try LIBPYTHON environment variable first.
  if (libpython = ENV['LIBPYTHON'])
    if File.file?(libpython)
      begin
        return dlopen(libpython)
      rescue Fiddle::DLError
        debug_report "#{$!.class}: #{$!.message}"
      else
        debug_report "Success to dlopen #{libpython.inspect} from ENV['LIBPYTHON']"
      end
    end
    warn "WARNING(#{self}.#{__method__}) Ignore the wrong libpython location specified in ENV['LIBPYTHON']."
  end

  # Find libpython (we hope):
  set_PYTHONHOME(python_config)
  libs = make_libs(python_config)
  libpaths = make_libpaths(python_config)
  multiarch = python_config[:MULTIARCH] || python_config[:multiarch]
  libs.each do |lib|
    libpaths.each do |libpath|
      libpath_libs = [ File.join(libpath, lib) ]
      libpath_libs << File.join(libpath, multiarch, lib) if multiarch
      libpath_libs.each do |libpath_lib|
        [ libpath_lib, "#{libpath_lib}.#{LIBSUFFIX}" ].each do |fullname|
          unless File.file? fullname
            debug_report "Unable to find #{fullname}"
            next
          end
          begin
            return dlopen(libpath_lib)
          rescue Fiddle::DLError
            debug_report "#{$!.class}: #{$!.message}"
          else
            debug_report "Success to dlopen #{libpaht_lib}"
          end
        end
      end
    end
  end

  # Find libpython in the system path
  libs.each do |lib|
    begin
      return dlopen(lib)
    rescue Fiddle::DLError
      debug_report "#{$!.class}: #{$!.message}"
    else
      debug_report "Success to dlopen #{lib}"
    end
  end

  raise ::PyCall::PythonNotFound
end

.find_python_config(python = nil) ⇒ Object



27
28
29
30
31
32
33
34
35
36
37
# File 'lib/pycall/libpython/finder.rb', line 27

def find_python_config(python = nil)
  python ||= DEFAULT_PYTHON
  Array(python).each do |python_cmd|
    begin
      python_config = investigate_python_config(python_cmd)
      return [python_cmd, python_config] unless python_config.empty?
    rescue
    end
  end
  raise ::PyCall::PythonNotFound
end

.investigate_python_config(python) ⇒ Object



98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
# File 'lib/pycall/libpython/finder.rb', line 98

def investigate_python_config(python)
  python_env = { 'PYTHONIOENCODING' => 'UTF-8' }
  debug_report("investigate_python_config(#{python.inspect})")
  IO.popen(python_env, [python, python_investigator_py], 'r') do |io|
    {}.tap do |config|
      io.each_line do |line|
        next unless line =~ /: /
        key, value = line.chomp.split(': ', 2)
        case value
        when 'True', 'true', 'False', 'false'
          value = (value == 'True' || value == 'true')
        end
        config[key.to_sym] = value if value != 'None'
      end
    end
  end
rescue Errno::ENOENT
  raise PyCall::PythonInvestigationFailed
end

.make_libpaths(python_config) ⇒ Object



151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
# File 'lib/pycall/libpython/finder.rb', line 151

def make_libpaths(python_config)
  executable = python_config[:executable]
  libpaths = [ python_config[:LIBDIR] ]
  if Fiddle::WINDOWS
    libpaths << File.dirname(executable)
  else
    libpaths << File.expand_path('../../lib', executable)
  end
  libpaths << python_config[:PYTHONFRAMEWORKPREFIX]
  exec_prefix = python_config[:exec_prefix]
  libpaths << exec_prefix << File.join(exec_prefix, 'lib')
  libpaths.compact!

  debug_report "libpaths: #{libpaths.inspect}"
  return libpaths
end

.make_libs(python_config) ⇒ Object



133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
# File 'lib/pycall/libpython/finder.rb', line 133

def make_libs(python_config)
  libs = []
  %i(INSTSONAME LDLIBRARY).each do |key|
    lib = python_config[key]
    libs << lib << File.basename(lib) if lib
  end
  if (lib = python_config[:LIBRARY])
    libs << File.basename(lib, File.extname(lib))
  end

  v = python_config[:VERSION]
  libs << "#{LIBPREFIX}python#{v}" << "#{LIBPREFIX}python"
  libs.uniq!

  debug_report "libs: #{libs.inspect}"
  return libs
end

.python_investigator_pyObject



118
119
120
# File 'lib/pycall/libpython/finder.rb', line 118

def python_investigator_py
  File.expand_path('../../python/investigator.py', __FILE__)
end

.set_PYTHONHOME(python_config) ⇒ Object



122
123
124
125
126
127
128
129
130
131
# File 'lib/pycall/libpython/finder.rb', line 122

def set_PYTHONHOME(python_config)
  if !ENV.has_key?('PYTHONHOME')
    case RUBY_PLATFORM
    when /mingw32/, /cygwin/, /mswin/
      ENV['PYTHONHOME'] = python_config[:exec_prefix]
    else
      ENV['PYTHONHOME'] = python_config.values_at(:prefix, :exec_prefix).join(':')
    end
  end
end