Relocate bottles using install_name_tool.

This has two parts:

1. Bottles are temporarily relocated on bottling and tested if that is
sufficient for them to contain no longer reference the prefix or
cellar. If so, they are marked as relocatable.
2. On installation if bottles are marked as relocatable they will be
relocated using install_name_tool to the current prefix and cellar.

Closes Homebrew/homebrew#18374.

Library/Homebrew/cmd/bottle.rb

@@ -1,8 +1,13 @@
 require 'formula'
 require 'bottles'
 require 'tab'
+require 'keg'
 
 module Homebrew extend self
+  def keg_contains string, keg
+    quiet_system 'fgrep', '--recursive', '--quiet', '--max-count=1', string, keg
+  end
+
   def bottle_formula f
     unless f.installed?
       return ofail "Formula not installed: #{f.name}"
@@ -18,23 +23,48 @@ module Homebrew extend self
     bottle_path = Pathname.pwd/filename
     sha1 = nil
 
+    prefix = HOMEBREW_PREFIX.to_s
+    tmp_prefix = '/tmp'
+    cellar = HOMEBREW_CELLAR.to_s
+    tmp_cellar = '/tmp/Cellar'
+
     HOMEBREW_CELLAR.cd do
       ohai "Bottling #{f.name} #{f.version}..."
-      bottle_relocatable = !quiet_system(
-        'grep', '--recursive', '--quiet', '--max-count=1',
-                HOMEBREW_CELLAR, "#{f.name}/#{f.version}")
-      cellar = nil
-      if bottle_relocatable
-        cellar = ':any'
-      elsif HOMEBREW_CELLAR.to_s != '/usr/local/Cellar'
-        cellar = "'#{HOMEBREW_CELLAR}'"
-      end
       # Use gzip, faster to compress than bzip2, faster to uncompress than bzip2
       # or an uncompressed tarball (and more bandwidth friendly).
       safe_system 'tar', 'czf', bottle_path, "#{f.name}/#{f.version}"
       sha1 = bottle_path.sha1
+      relocatable = false
+
+      keg = Keg.new f.prefix
+      keg.lock do
+        # Relocate bottle library references before testing for built-in
+        # references to the Cellar e.g. Qt's QMake annoyingly does this.
+        keg.relocate_install_names prefix, tmp_prefix, cellar, tmp_cellar
+
+        relocatable = !keg_contains(HOMEBREW_PREFIX, keg)
+        relocatable = !keg_contains(HOMEBREW_CELLAR, keg) if relocatable
+
+        # And do the same thing in reverse to change the library references
+        # back to how they were.
+        keg.relocate_install_names tmp_prefix, prefix, tmp_cellar, cellar
+      end
+
+      prefix = cellar = nil
+      if relocatable
+        cellar = ':any'
+      else
+        if HOMEBREW_PREFIX.to_s != '/usr/local'
+          prefix = "'#{HOMEBREW_PREFIX}"
+        end
+        if HOMEBREW_CELLAR.to_s != '/usr/local/Cellar'
+          cellar = "'#{HOMEBREW_CELLAR}'"
+        end
+      end
+
       puts "./#{filename}"
       puts "bottle do"
+      puts "  prefix #{prefix}" if prefix
       puts "  cellar #{cellar}" if cellar
       puts "  revision #{bottle_revision}" if bottle_revision > 0
       puts "  sha1 '#{sha1}' => :#{MacOS.cat}"

Library/Homebrew/formula_installer.rb

@@ -96,13 +96,13 @@ class FormulaInstaller
     begin
       if pour_bottle?
         pour
-        poured_bottle = true
+        @poured_bottle = true
       end
     rescue
       opoo "Bottle installation failed: building from source."
     end
 
-    unless poured_bottle
+    unless @poured_bottle
       build
       clean
     end
@@ -353,6 +353,17 @@ class FormulaInstaller
 
   def fix_install_names
     Keg.new(f.prefix).fix_install_names
+    if @poured_bottle
+      old_prefix = f.bottle.prefix
+      new_prefix = HOMEBREW_PREFIX.to_s
+      old_cellar = f.bottle.cellar
+      new_cellar = HOMEBREW_CELLAR.to_s
+
+      if old_prefix != new_prefix or old_cellar != new_cellar
+        Keg.new(f.prefix).relocate_install_names \
+          old_prefix, new_prefix, old_cellar, new_cellar
+      end
+    end
   rescue Exception => e
     onoe "Failed to fix install names"
     puts "The formula built, but you may encounter issues using it or linking other"

Library/Homebrew/formula_support.rb

@@ -85,6 +85,7 @@ class Bottle < SoftwareSpec
   def initialize
     super
     @revision = 0
+    @prefix = '/usr/local'
     @cellar = '/usr/local/Cellar'
     @cat_without_underscores = false
   end
@@ -117,6 +118,10 @@ class Bottle < SoftwareSpec
     val.nil? ? @root_url : @root_url = val
   end
 
+  def prefix val=nil
+    val.nil? ? @prefix : @prefix = val
+  end
+
   def cellar val=nil
     val.nil? ? @cellar : @cellar = val
   end

Library/Homebrew/keg_fix_install_names.rb

@@ -2,7 +2,7 @@ class Keg
   def fix_install_names
     return unless MACOS
     mach_o_files.each do |file|
-      bad_install_names_for file do |id, bad_names|
+      install_names_for file do |id, bad_names|
         file.ensure_writable do
           system MacOS.locate("install_name_tool"), "-id", id, file if file.dylib?
 
@@ -31,13 +31,50 @@ class Keg
     end
   end
 
+  def relocate_install_names old_prefix, new_prefix, old_cellar, new_cellar
+    mach_o_files.each do |file|
+      install_names_for(file, relocate_reject_proc(old_prefix)) do |id, old_prefix_names|
+        file.ensure_writable do
+          new_prefix_id = id.to_s.gsub old_prefix, new_prefix
+          system MacOS.locate("install_name_tool"), "-id", new_prefix_id, file if file.dylib?
+
+          old_prefix_names.each do |old_prefix_name|
+            new_prefix_name = old_prefix_name.to_s.gsub old_prefix, new_prefix
+            system MacOS.locate("install_name_tool"), "-change", old_prefix_name, new_prefix_name, file
+          end
+        end
+      end
+
+      install_names_for(file, relocate_reject_proc(old_cellar)) do |id, old_cellar_names|
+        file.ensure_writable do
+          old_cellar_names.each do |old_cellar_name|
+            new_cellar_name = old_cellar_name.to_s.gsub old_cellar, new_cellar
+            system MacOS.locate("install_name_tool"), "-change", old_cellar_name, new_cellar_name, file
+          end
+        end
+      end
+    end
+  end
+
   private
 
   OTOOL_RX = /\t(.*) \(compatibility version (\d+\.)*\d+, current version (\d+\.)*\d+\)/
 
   def lib; join 'lib' end
 
-  def bad_install_names_for file
+  def default_reject_proc
+    Proc.new do |fn|
+      # Don't fix absolute paths unless they are rooted in the build directory
+      tmp = ENV['HOMEBREW_TEMP'] ? Regexp.escape(ENV['HOMEBREW_TEMP']) : '/tmp'
+      fn[0,1] == '/' and not %r[^#{tmp}] === fn
+    end
+  end
+
+  def relocate_reject_proc(path)
+    Proc.new { |fn| not fn.start_with?(path) }
+  end
+
+  def install_names_for file, reject_proc=default_reject_proc
     ENV['HOMEBREW_MACH_O_FILE'] = file.to_s # solves all shell escaping problems
     install_names = `#{MacOS.locate("otool")} -L "$HOMEBREW_MACH_O_FILE"`.split "\n"
 
@@ -49,12 +86,7 @@ class Keg
 
     install_names.compact!
     install_names.reject!{ |fn| fn =~ /^@(loader_|executable_|r)path/ }
-
-    # Don't fix absolute paths unless they are rooted in the build directory
-    install_names.reject! do |fn|
-      tmp = ENV['HOMEBREW_TEMP'] ? Regexp.escape(ENV['HOMEBREW_TEMP']) : '/tmp'
-      fn[0,1] == '/' and not %r[^#{tmp}] === fn
-    end
+    install_names.reject!{ |fn| reject_proc.call(fn) }
 
     # the shortpath ensures that library upgrades don’t break installed tools
     relative_path = Pathname.new(file).relative_path_from(self)

Library/Homebrew/test/testball.rb

@@ -221,6 +221,7 @@ class AllCatsBottleSpecTestBall < Formula
   sha1 '482e737739d946b7c8cbaf127d9ee9c148b999f5'
 
   bottle do
+    prefix '/private/tmp/testbrew/prefix'
     cellar '/private/tmp/testbrew/cellar'
     sha1 'deadbeefdeadbeefdeadbeefdeadbeefdeadbeef' => :snow_leopard_32
     sha1 'faceb00cfaceb00cfaceb00cfaceb00cfaceb00c' => :snow_leopard