Fix: detect ICU symbols' suffix from .so file at compile time

.travis.yml

@@ -1,12 +1,61 @@
 ---
 language: crystal
-dist: trusty
 sudo: required
 
-before_install:
-- sudo apt-get -qq update
-- sudo apt-get install -y pkg-config libicu52
+matrix:
+  allow_failures: # FIXME: temporary fix, see https://github.com/olbat/icu.cr/issues/2
+  - os: osx
+  include:
+  # Linux
+  - os: linux
+    dist: precise
+  - os: linux
+    dist: trusty
+  - os: linux
+    dist: xenial
+  - os: linux
+    dist: trusty
+    env: GENERATE_LIB=1 # regenerate the binding
+  # OSX
+  - os: osx
+    osx_image: xcode8.3
+  - os: osx
+    osx_image: xcode8.3
+    env: GENERATE_LIB=1 # regenerate the binding
+
+before_install: |
+  case $TRAVIS_OS_NAME in
+  linux)
+    sudo apt-get -qq update
+    if [[ -n $GENERATE_LIB ]]; then
+      sudo apt-get install -y llvm-3.5-dev libclang-3.5-dev
+    fi
+    sudo apt-get install -y libicu-dev
+    ;;
+  osx)
+    brew update
+
+    # FIXME: ugly fix for the CI's image, crystal-lang should not be reinstalled
+    rm -f /usr/local/bin/shards
+    brew install crystal-lang
+
+    if [[ -n $GENERATE_LIB ]]; then
+      # install LLVM and Clang 3.7
+      brew install [email protected]
+      # FIXME: ugly fix since the libclang.dylib is not symlinked correctly
+      brew list --verbose [email protected] | grep "\.dylib$" | xargs -n1 -I{} ln -sf {} $(brew --prefix)/lib
+    fi
+
+    brew install icu4c
+    brew link --force icu4c
+    ;;
+  *)
+    exit 1;;
+  esac
+
+before_script:
+- "[ -z $GENERATE_LIB ] || make"
 
 script:
-- crystal tool format --check
+- crystal tool format --check src spec
 - crystal spec

Makefile

@@ -0,0 +1,21 @@
+CRBIN=crystal
+LGBIN=lib/libgen/bin/libgen
+LGCONF=lib.yml
+GENSRC=src/lib_generator.cr
+
+generate_lib: $(LGBIN) $(LGCONF)
+	rm -rf src/lib_icu
+	$(LGBIN) $(LGCONF)
+	$(CRBIN) run $(GENSRC)
+
+$(LGBIN): lib/libgen
+	cd lib/libgen && $(CRBIN) deps build
+
+lib/libgen: shard.yml
+	$(CRBIN) deps install
+
+clean:
+	rm -rf lib
+	rm -rf .crystal
+
+.PHONY: clean

lib.yml

@@ -1,7 +1,7 @@
 ---
 name: LibICU
-ldflags: "-licuio -licui18n -liculx -licule -licuuc -licudata"
-packages: "icu-uc icu-i18n icu-io icu-lx icu-le"
+ldflags: "-licuio -licui18n -licuuc -licudata"
+packages: "icu-uc icu-i18n icu-io"
 destdir: src/lib_icu/
 rename:
   rules:

shard.yml

@@ -10,6 +10,11 @@ description: |
   A binding to the ICU library
 
 libraries:
-  libicu: "~> 52.0" # FIXME: see https://github.com/olbat/icu.cr/issues/1
+  libicu: ">= 4.8"
+
+development_dependencies:
+  libgen:
+    github: olbat/libgen
+    #version: ~> 0.1
 
 license: GPLv3

spec/currencies_spec.cr

@@ -13,6 +13,7 @@ describe "ICU::Currencies" do
     end
   end
 
+  {% if compare_versions(LibICU::VERSION, "49.0.0") >= 0 %}
   describe "numeric_code" do
     it "returns the code associated to a currency" do
       ICU::Currencies.numeric_code("EUR").should eq(978)
@@ -24,4 +25,5 @@ describe "ICU::Currencies" do
       end
     end
   end
+  {% end %}
 end

spec/icu_info_spec.cr

@@ -0,0 +1,20 @@
+require "./spec_helper"
+require "../src/icu_info"
+
+describe "icu_version" do
+  it "returns the version of the ICU lib" do
+    icu_version().should match(/^[0-9][0-9\.]*$/)
+  end
+end
+
+describe "icu_sem_version" do
+  it "returns the version of the ICU lib in semantic versioning format" do
+    icu_sem_version().should match(/^[0-9]+\.[0-9]+\.[0-9]+$/)
+  end
+end
+
+describe "icu_so_symbols_suffix" do
+  it "returns the version suffix added to symbols in so files of the ICU lib" do
+    icu_so_symbols_suffix().should match(/^[0-9_]*$/)
+  end
+end

spec/region_spec.cr

@@ -1,5 +1,6 @@
 require "./spec_helper"
 
+{% if compare_versions(LibICU::VERSION, "52.0.0") >= 0 %}
 describe "ICU::Region" do
   describe "initialize" do
     it "creates a new region from a code" do
@@ -57,3 +58,4 @@ describe "ICU::Region" do
     end
   end
 end
+{% end %}

src/icu/currencies.cr

@@ -16,9 +16,11 @@ class ICU::Currencies
     ICU.uchars_to_string(buff, len)
   end
 
+  {% if compare_versions(LibICU::VERSION, "49.0.0") >= 0 %}
   def self.numeric_code(currency : String) : Int32
     num = LibICU.ucurr_get_numeric_code(ICU.string_to_uchars(currency))
     raise ICU::Error.new(%(Unknown currency "#{currency}")) if num == 0
     num
   end
+  {% end %}
 end

src/icu/region.cr

@@ -1,3 +1,4 @@
+{% if compare_versions(LibICU::VERSION, "52.0.0") >= 0 %}
 class ICU::Region
   @uregion : LibICU::URegion
   @code : String?
@@ -47,3 +48,4 @@ class ICU::Region
     regions.map { |r| self.class.new(r) }
   end
 end
+{% end %}

src/icu_info.cr

@@ -0,0 +1,101 @@
+require "xml"
+require "c/dlfcn"
+
+PKGNAME  = "icu-uc"
+TESTFUNC = "u_init"
+{% if flag?(:darwin) %}
+SOFILE   = "libicuuc.dylib"
+{% elsif flag?(:windows) %}
+SOFILE   = "libicuuc.dll"
+{% else %}
+SOFILE   = "libicuuc.so"
+{% end %}
+
+def icu_version : String
+  version = nil
+  if system("command -v icuinfo > /dev/null")
+    icuinfo = `icuinfo -v`
+    begin
+      doc = XML.parse(icuinfo)
+      if params = doc.first_element_child
+        if params.name == "icuSystemParams" # ICU >= 49.0
+          params.children.select(&.element?).each do |param|
+            if param.name == "param" && param["name"]? == "version"
+              version = param.content.strip
+              break
+            end
+          end
+        elsif params.name == "ICUINFO" # ICU < 49.0
+          if v = params.content.match(/Compiled-Version\s*:\s*([0-9\.]+)/)
+            version = v[1]
+          end
+        end
+      end
+    rescue XML::Error
+    end
+  else
+    STDERR.puts %(WARNING: cannot find the "icuinfo" tool in PATH)
+    {% if flag?(:darwin) %}
+    STDERR.puts %(\t(on OSX, please check that you've run "brew link icu4c"))
+    {% end %}
+  end
+
+  if !version && system("command -v pkg-config > /dev/null")
+    version = `pkg-config --modversion #{PKGNAME}`.strip
+  end
+
+  abort("cannot find ICU version", 3) if !version || version.empty?
+
+  version
+end
+
+def icu_sem_version : String
+  # convert ICU version to semantic versioning
+  version = icu_version()
+  v = version.split(".")
+  if v.size == 3
+    version
+  elsif v.size > 3
+    v[0..2].join(".")
+  else
+    3.times.map { |i| v[i]? || "0" }.join(".")
+  end
+end
+
+def icu_possible_suffixes(version : String) : Array(String)
+  v = version.split(".")
+  [
+    "",
+    "_#{version}",
+    "_#{v[0]}",
+    "_#{v[0]}#{v[1]}",
+    "_#{v[0]}_#{v[1]}",
+    "_#{v[0][0]}_#{v[0][1]? || v[1][0]}",
+  ].uniq
+end
+
+def icu_so_symbols_suffix
+  suffixes = icu_possible_suffixes(icu_version())
+
+  handle = LibC.dlopen(SOFILE, LibC::RTLD_LAZY)
+  abort("cannot load the #{SOFILE} file", 1) if handle.null?
+
+  begin
+    suffixes.each do |suffix|
+      LibC.dlsym(handle, "#{TESTFUNC}#{suffix}")
+      return suffix if LibC.dlerror.null?
+    end
+    abort("cannot find so symbols suffix", 2)
+  ensure
+    LibC.dlclose(handle)
+  end
+end
+
+case ARGV[0]?
+when "--version"
+  puts icu_version()
+when "--sem-version"
+  puts icu_sem_version()
+when "--so-symbols-suffix"
+  puts icu_so_symbols_suffix()
+end

src/lib_generator.cr

@@ -0,0 +1,34 @@
+require "compiler/crystal/tools/formatter"
+
+LIB_DIR  = "lib_icu"
+ICU_INFO = "icu_info.cr"
+
+Dir[File.join(File.dirname(__FILE__), LIB_DIR, "**", "*.cr")].each do |file|
+  abort "cannot read #{file}" unless File.readable?(file)
+  src = File.read(file)
+  src = Crystal.format(src)
+
+  # run the suffix finder program to initialize the SYMS_SUFFIX constant
+  # in the common lib file
+  if File.basename(file) == "#{LIB_DIR}.cr"
+    constdef = <<-EOS
+      VERSION={{ run("../#{ICU_INFO}", "--sem-version").strip.stringify }}
+      SYMS_SUFFIX={{ run("../#{ICU_INFO}", "--so-symbols-suffix").strip.stringify }}
+      {% end %}
+
+      {% begin %}
+
+    EOS
+  else
+    constdef = ""
+  end
+
+  # add macro blocks in the body of every lib files
+  src = src.gsub(/^(lib \w+)\n(.+)end$/m, "\\1\n  {% begin %}\n#{constdef}\\2  {% end %}\nend")
+
+  # replace the current suffix by the SYMS_SUFFIX constant (macro)
+  src = src.gsub(/^(\s*fun\s+\w+\s*=\s*\w+?)(_[0-9_]+)?([\(\s:]|$)/m, "\\1{{SYMS_SUFFIX.id}}\\3")
+
+  abort "cannot write #{file}" unless File.writable?(file)
+  File.write(file, Crystal.format(src))
+end