Class: Rubycc::Pkgconf::Resolver

Inherits:
Object
  • Object
show all
Defined in:
lib/rubycc/pkgconf/resolver.rb

Overview

Loads .pc files by name from a search path and walks their Requires chain to produce the token lists --cflags/--libs need. A module is loaded at most once per Resolver (a memoizing cache doubling as the cycle guard for a Requires loop); within a single module's own Cflags/Libs value, tokens are kept exactly as written — no de-duplication is attempted (see the Step 59 report: this cannot be measured against the real pkg-config in this environment, so the simplest order-preserving concatenation is used, which is all mkmf's pkg_config() needs).

Instance Method Summary collapse

Constructor Details

#initialize(directories: SearchPath.directories) ⇒ Resolver

Returns a new instance of Resolver.



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# File 'lib/rubycc/pkgconf/resolver.rb', line 16

def initialize(directories: SearchPath.directories)
  @directories = directories
  @cache = {}
end

Instance Method Details

#cflags_tokens(name, visited = {}) ⇒ Object

Own Cflags, then each public Requires recursively, then each Requires.private recursively — a private dependency's compiler flags are still needed to build against name, they are just not exposed to its dependents (that asymmetry is Requires.private's whole point).



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# File 'lib/rubycc/pkgconf/resolver.rb', line 44

def cflags_tokens(name, visited = {})
  return [] if visited[name]

  visited[name] = true
  pkg = load(name)
  tokens = Shellwords.split(pkg.cflags)
  pkg.requires.each { |dep| tokens.concat(cflags_tokens(dep, visited)) }
  pkg.requires_private.each { |dep| tokens.concat(cflags_tokens(dep, visited)) }
  tokens
end

#exists?(name) ⇒ Boolean

True if name and its whole Requires/Requires.private chain resolve — the same thing pkg-config --exists has to check, since it must load every dependency's .pc file to answer the question.

Returns:

  • (Boolean) 


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# File 'lib/rubycc/pkgconf/resolver.rb', line 24

def exists?(name)
  cflags_tokens(name)
  true
rescue PkgconfError
  false
end

#libs_tokens(name, visited = {}) ⇒ Object

Own Libs, then each public Requires recursively. Requires.private never contributes here — pkg-config only pulls a private dependency's Libs into the static-link case (Libs.private via --static), which mkmf's pkg_config() never requests, so it is out of scope.



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# File 'lib/rubycc/pkgconf/resolver.rb', line 59

def libs_tokens(name, visited = {})
  return [] if visited[name]

  visited[name] = true
  pkg = load(name)
  tokens = Shellwords.split(pkg.libs)
  pkg.requires.each { |dep| tokens.concat(libs_tokens(dep, visited)) }
  tokens
end

#load(name) ⇒ Object

Raises:



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# File 'lib/rubycc/pkgconf/resolver.rb', line 31

def load(name)
  return @cache[name] if @cache.key?(name)

  path = SearchPath.find(name, directories: @directories)
  raise NotFoundError, "package '#{name}' not found (searched #{@directories.join(File::PATH_SEPARATOR)})" unless path

  @cache[name] = Parser.parse(File.read(path), path: path)
end