simplify image_readers creation implementation

* remove static callbacks registration
* link png_reader/jpeg_reader into mbgl-linux lib

11 files changed, 156 insertions, 347 deletions

diff --git a/gyp/mbgl-linux.gypi b/gyp/mbgl-linux.gypi
index a66a80ebfa..aee928685a 100644
--- a/gyp/mbgl-linux.gypi
+++ b/gyp/mbgl-linux.gypi
@@ -8,6 +8,7 @@
       'variables': {
         'cflags_cc': [
           '<@(png_cflags)',
+	  '<@(jpeg_cflags)',
           '<@(uv_cflags)',
           '<@(curl_cflags)',
           '<@(nu_cflags)',
@@ -32,6 +33,8 @@
         '../platform/default/http_request_baton_curl.cpp',
         '../platform/default/image.cpp',
         '../platform/default/image_reader.cpp',
+        '../platform/default/png_reader.cpp',
+        '../platform/default/jpeg_reader.cpp',
       ],
       'include_dirs': [
         '../include',
diff --git a/include/mbgl/util/factory.hpp b/include/mbgl/util/factory.hpp
deleted file mode 100644
index 1ffcac6f92..0000000000
--- a/include/mbgl/util/factory.hpp
+++ /dev/null
@@ -1,55 +0,0 @@
-#ifndef MBGL_UTIL_FACTORY_HPP
-#define MBGL_UTIL_FACTORY_HPP
-
-// stl
-#include <stdexcept>
-#include <mutex>
-#include <map>
-
-namespace mbgl { namespace util {
-
-template
-<
-typename product_type,
-typename key_type,
-typename ...Args >
-class factory
-{
-public:
-    using product_creator = product_type* (*) (Args...);
-    using product_map = std::map<key_type,product_creator>;
-    static product_map map_;
-    static std::mutex mutex_;
-public:
-
-    static bool register_product(key_type const& key, product_creator creator)
-    {
-        std::unique_lock<std::mutex> lock(mutex_);
-        return map_.insert(typename product_map::value_type(key,creator)).second;
-    }
-
-    static bool unregister_product(const key_type& key)
-    {
-        std::unique_lock<std::mutex> lock(mutex_);
-        return map_.erase(key)==1;
-    }
-
-    static product_type* create_object(key_type const& key, Args...args)
-    {
-        typename product_map::const_iterator pos=map_.find(key);
-        if (pos!=map_.end())
-        {
-            return (pos->second)(args...);
-        }
-        return 0;
-    }
-};
-
-template <typename product_type, typename key_type, typename ...Args>
-typename factory<product_type, key_type, Args...>::product_map factory<product_type, key_type, Args...>::map_;
-template <typename product_type, typename key_type, typename ...Args>
-typename std::mutex factory<product_type, key_type, Args...>::mutex_;
-
-}}
-
-#endif
diff --git a/include/mbgl/util/image_reader.hpp b/include/mbgl/util/image_reader.hpp
index 144127b76e..589653ec5c 100644
--- a/include/mbgl/util/image_reader.hpp
+++ b/include/mbgl/util/image_reader.hpp
@@ -1,7 +1,6 @@
 #ifndef MBGL_UTIL_IMAGE_READER_HPP
 #define MBGL_UTIL_IMAGE_READER_HPP
 
-#include "factory.hpp"
 #include "noncopyable.hpp"
 // stl
 #include <stdexcept>
@@ -35,12 +34,6 @@ struct image_reader : private noncopyable
     virtual ~image_reader() {}
 };
 
-template <typename...Args>
-bool register_image_reader(std::string const& type, image_reader* (* fun)(Args...))
-{
-    return factory<image_reader,std::string, Args...>::register_product(type, fun);
-}
-
 image_reader* get_image_reader(char const* data, size_t size);
 
 }}
diff --git a/include/mbgl/util/jpeg_reader.hpp b/include/mbgl/util/jpeg_reader.hpp
new file mode 100644
index 0000000000..77356007d8
--- /dev/null
+++ b/include/mbgl/util/jpeg_reader.hpp
@@ -0,0 +1,69 @@
+#ifndef MBGL_UTIL_JPEG_READER_HPP
+#define MBGL_UTIL_JPEG_READER_HPP
+
+#include "image_reader.hpp"
+
+// jpeg
+extern "C"
+{
+#include <jpeglib.h>
+}
+
+#include <boost/iostreams/stream.hpp>
+
+namespace mbgl { namespace util {
+
+template <typename T>
+class jpeg_reader : public image_reader
+{
+public:
+    using source_type = T;
+    using input_stream = boost::iostreams::stream<source_type>;
+    const static unsigned BUF_SIZE = 4096;
+private:
+    struct jpeg_stream_wrapper
+    {
+        jpeg_source_mgr manager;
+        input_stream * stream;
+        JOCTET buffer[BUF_SIZE];
+    };
+
+    struct jpeg_info_guard
+    {
+        jpeg_info_guard(jpeg_decompress_struct * cinfo)
+            : i_(cinfo) {}
+
+        ~jpeg_info_guard()
+        {
+            jpeg_destroy_decompress(i_);
+        }
+        jpeg_decompress_struct * i_;
+    };
+
+private:
+    source_type source_;
+    input_stream stream_;
+    unsigned width_;
+    unsigned height_;
+public:
+    jpeg_reader(char const* data, size_t size);
+    ~jpeg_reader();
+    unsigned width() const;
+    unsigned height() const;
+    inline bool has_alpha() const { return false; }
+    inline bool premultiplied_alpha() const { return true; }
+    void read(unsigned x,unsigned y, unsigned w, unsigned h, char *image);
+private:
+    void init();
+    static void on_error(j_common_ptr cinfo);
+    static void on_error_message(j_common_ptr cinfo);
+    static void init_source(j_decompress_ptr cinfo);
+    static boolean fill_input_buffer(j_decompress_ptr cinfo);
+    static void skip(j_decompress_ptr cinfo, long count);
+    static void term(j_decompress_ptr cinfo);
+    static void attach_stream(j_decompress_ptr cinfo, input_stream* in);
+};
+
+}}
+
+#endif // MBGL_UTIL_JPEG_READER_HPP
diff --git a/include/mbgl/util/png_reader.hpp b/include/mbgl/util/png_reader.hpp
new file mode 100644
index 0000000000..3d6e1db51e
--- /dev/null
+++ b/include/mbgl/util/png_reader.hpp
@@ -0,0 +1,62 @@
+#ifndef MBGL_UTIL_PNG_READER_HPP
+#define MBGL_UTIL_PNG_READER_HPP
+
+#include "mbgl/util/image_reader.hpp"
+
+extern "C"
+{
+#include <png.h>
+}
+
+#include <cstring>
+#include <memory>
+
+#include <boost/iostreams/stream.hpp>
+
+namespace mbgl { namespace util {
+
+template <typename T>
+class png_reader : public image_reader
+{
+    using source_type = T;
+    using input_stream = boost::iostreams::stream<source_type>;
+
+    struct png_struct_guard
+    {
+        png_struct_guard(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
+            : p_(png_ptr_ptr),
+              i_(info_ptr_ptr) {}
+
+        ~png_struct_guard()
+        {
+            png_destroy_read_struct(p_,i_,0);
+        }
+        png_structpp p_;
+        png_infopp i_;
+    };
+
+private:
+    source_type source_;
+    input_stream stream_;
+    unsigned width_;
+    unsigned height_;
+    int bit_depth_;
+    int color_type_;
+    bool has_alpha_;
+public:
+    png_reader(char const* data, std::size_t size);
+    ~png_reader();
+    unsigned width() const;
+    unsigned height() const;
+    inline bool has_alpha() const { return has_alpha_; }
+    bool premultiplied_alpha() const { return false; } //http://www.libpng.org/pub/png/spec/1.1/PNG-Rationale.html
+    void read(unsigned x,unsigned y, unsigned width, unsigned height, char * image);
+private:
+    void init();
+    static void png_read_data(png_structp png_ptr, png_bytep data, png_size_t length);
+};
+
+
+}}
+
+#endif // MBGL_UTIL_PNG_READER_HPP
diff --git a/include/mbgl/util/singleton.hpp b/include/mbgl/util/singleton.hpp
deleted file mode 100644
index a1c1e3ebff..0000000000
--- a/include/mbgl/util/singleton.hpp
+++ /dev/null
@@ -1,126 +0,0 @@
-#ifndef MBGL_UTIL_SINGLETON_HPP
-#define MBGL_UTIL_SINGLETON_HPP
-
-// stl
-#include <stdexcept> // std::runtime_error
-#include <cstdlib> // std::atexit
-#include <new> // operator new
-#define SINGLETON_THREADSAFE
-#ifdef SINGLETON_THREADSAFE
-#include <mutex>
-#endif
-
-namespace mbgl { namespace util {
-
-template <typename T>
-class CreateUsingNew
-{
-public:
-    static T* create()
-    {
-        return new T;
-    }
-    static void destroy(T* obj)
-    {
-        delete obj;
-    }
-};
-
-template <typename T>
-class CreateStatic
-{
-private:
-    union MaxAlign
-    {
-        char t_[sizeof(T)];
-        short int shortInt_;
-        int int_;
-        long int longInt_;
-        float float_;
-        double double_;
-        long double longDouble_;
-        struct Test;
-        int Test::* pMember_;
-        int (Test::*pMemberFn_)(int);
-    };
-
-public:
-
-    static T* create()
-    {
-        static MaxAlign staticMemory;
-        return new(&staticMemory) T;
-    }
-    static void destroy(volatile T* obj)
-    {
-        obj->~T();
-    }
-};
-
-template <typename T,
-          template <typename U> class CreatePolicy=CreateStatic> class singleton
-{
-    friend class CreatePolicy<T>;
-    static T* pInstance_;
-    static bool destroyed_;
-    singleton(const singleton &rhs);
-    singleton& operator=(const singleton&);
-
-    static void onDeadReference()
-    {
-        throw std::runtime_error("dead reference!");
-    }
-
-    static void DestroySingleton()
-    {
-        CreatePolicy<T>::destroy(pInstance_);
-        pInstance_ = 0;
-        destroyed_ = true;
-    }
-
-protected:
-
-#ifdef SINGLETON_THREADSAFE
-        static std::mutex mutex_;
-#endif
-        singleton() {}
-    public:
-        static T& instance()
-        {
-            if (! pInstance_)
-            {
-#ifdef SINGLETON_THREADSAFE
-                std::unique_lock<std::mutex> lock(mutex_);
-#endif
-                if (! pInstance_)
-                {
-                    if (destroyed_)
-                    {
-                        destroyed_ = false;
-                        onDeadReference();
-                    }
-                    else
-                    {
-                        pInstance_ = CreatePolicy<T>::create();
-                        // register destruction
-                        std::atexit(&DestroySingleton);
-                    }
-                }
-            }
-            return *pInstance_;
-        }
-};
-
-#ifdef SINGLETON_THREADSAFE
-    template <typename T,
-              template <typename U> class CreatePolicy> std::mutex singleton<T,CreatePolicy>::mutex_;
-#endif
-
-    template <typename T,
-              template <typename U> class CreatePolicy> T* singleton<T,CreatePolicy>::pInstance_=0;
-    template <typename T,
-              template <typename U> class CreatePolicy> bool singleton<T,CreatePolicy>::destroyed_=false;
-
-}}
-
-#endif //
diff --git a/linux/mapboxgl-app.gyp b/linux/mapboxgl-app.gyp
index dbcc4b4479..fbeabd74ea 100644
--- a/linux/mapboxgl-app.gyp
+++ b/linux/mapboxgl-app.gyp
@@ -12,8 +12,6 @@
         '../platform/default/settings_json.cpp',
         '../platform/default/glfw_view.cpp',
         '../platform/default/log_stderr.cpp',
-        '../platform/default/png_reader.cpp',
-        '../platform/default/jpeg_reader.cpp',
       ],
       'xcode_settings': {
         'OTHER_CPLUSPLUSFLAGS':[
diff --git a/platform/default/image_reader.cpp b/platform/default/image_reader.cpp
index 53ab5758aa..599ccb13a4 100644
--- a/platform/default/image_reader.cpp
+++ b/platform/default/image_reader.cpp
@@ -1,5 +1,9 @@
 #include "mbgl/util/image_reader.hpp"
+#include "mbgl/util/png_reader.hpp"
+#include "mbgl/util/jpeg_reader.hpp"
+
 #include <boost/optional.hpp>
+#include <boost/iostreams/device/array.hpp>
 
 namespace mbgl { namespace util {
 
@@ -43,10 +47,16 @@ image_reader* get_image_reader(char const* data, size_t size)
     boost::optional<std::string> type = type_from_bytes(data,size);
     if (type)
     {
-        return factory<image_reader,std::string,char const*,size_t>::create_object(*type, data,size);
+        if (*type == "png")
+        {
+            return new png_reader<boost::iostreams::array_source>(data, size);
+        }
+        else if (*type == "jpeg")
+        {
+            return new jpeg_reader<boost::iostreams::array_source>(data, size);
+        }
     }
-    else
-        throw image_reader_exception("image_reader: can't determine type from input data");
+    throw image_reader_exception("image_reader: can't determine type from input data");
 }
 
 }}
diff --git a/platform/default/jpeg_reader.cpp b/platform/default/jpeg_reader.cpp
index f1e9d0fdfe..b722c08fa1 100644
--- a/platform/default/jpeg_reader.cpp
+++ b/platform/default/jpeg_reader.cpp
@@ -1,15 +1,9 @@
-#include "mbgl/util/image_reader.hpp"
-
-// jpeg
-extern "C"
-{
-#include <jpeglib.h>
-}
+#include "mbgl/util/jpeg_reader.hpp"
 
 // boost
 #include <boost/iostreams/device/file.hpp>
 #include <boost/iostreams/device/array.hpp>
-#include <boost/iostreams/stream.hpp>
+
 
 // std
 #include <cstdio>
@@ -17,80 +11,7 @@ extern "C"
 
 namespace mbgl { namespace util {
 
-template <typename T>
-class jpeg_reader : public image_reader
-{
-public:
-    using source_type = T;
-    using input_stream = boost::iostreams::stream<source_type>;
-    const static unsigned BUF_SIZE = 4096;
-private:
-    struct jpeg_stream_wrapper
-    {
-        jpeg_source_mgr manager;
-        input_stream * stream;
-        JOCTET buffer[BUF_SIZE];
-    };
-
-    struct jpeg_info_guard
-    {
-        jpeg_info_guard(jpeg_decompress_struct * cinfo)
-            : i_(cinfo) {}
-
-        ~jpeg_info_guard()
-        {
-            jpeg_destroy_decompress(i_);
-        }
-        jpeg_decompress_struct * i_;
-    };
-
-private:
-    source_type source_;
-    input_stream stream_;
-    unsigned width_;
-    unsigned height_;
-public:
-    explicit jpeg_reader(std::string const& file_name);
-    explicit jpeg_reader(char const* data, size_t size);
-    ~jpeg_reader();
-    unsigned width() const;
-    unsigned height() const;
-    inline bool has_alpha() const { return false; }
-    inline bool premultiplied_alpha() const { return true; }
-    void read(unsigned x,unsigned y, unsigned w, unsigned h, char *image);
-private:
-    void init();
-    static void on_error(j_common_ptr cinfo);
-    static void on_error_message(j_common_ptr cinfo);
-    static void init_source(j_decompress_ptr cinfo);
-    static boolean fill_input_buffer(j_decompress_ptr cinfo);
-    static void skip(j_decompress_ptr cinfo, long count);
-    static void term(j_decompress_ptr cinfo);
-    static void attach_stream(j_decompress_ptr cinfo, input_stream* in);
-};
-
-namespace
-{
-image_reader* create_jpeg_reader(char const* data, size_t size)
-{
-    return new jpeg_reader<boost::iostreams::array_source>(data, size);
-}
-
-const static bool registered = register_image_reader("jpeg",create_jpeg_reader);
-}
-
-// ctors
-template <typename T>
-jpeg_reader<T>::jpeg_reader(std::string const& file_name)
-    : source_(file_name,std::ios_base::in | std::ios_base::binary),
-      stream_(source_),
-      width_(0),
-      height_(0)
-{
-    if (!stream_) throw image_reader_exception("cannot open image file "+ file_name);
-    init();
-}
-
+// ctor
 template <typename T>
 jpeg_reader<T>::jpeg_reader(char const* data, size_t size)
     : source_(data, size),
@@ -277,4 +198,6 @@ void jpeg_reader<T>::read(unsigned x0, unsigned y0, unsigned w, unsigned h, char
     jpeg_finish_decompress(&cinfo);
 }
 
+template class jpeg_reader<boost::iostreams::array_source>;
+
 }}
diff --git a/platform/default/png_reader.cpp b/platform/default/png_reader.cpp
index 838344286e..4d0abce04c 100644
--- a/platform/default/png_reader.cpp
+++ b/platform/default/png_reader.cpp
@@ -1,4 +1,4 @@
-#include "mbgl/util/image_reader.hpp"
+#include "mbgl/util/png_reader.hpp"
 #include <iostream>
 extern "C"
 {
@@ -16,61 +16,6 @@ extern "C"
 
 namespace mbgl { namespace util {
 
-template <typename T>
-class png_reader : public image_reader
-{
-    using source_type = T;
-    using input_stream = boost::iostreams::stream<source_type>;
-
-    struct png_struct_guard
-    {
-        png_struct_guard(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
-            : p_(png_ptr_ptr),
-              i_(info_ptr_ptr) {}
-
-        ~png_struct_guard()
-        {
-            png_destroy_read_struct(p_,i_,0);
-        }
-        png_structpp p_;
-        png_infopp i_;
-    };
-
-private:
-
-    source_type source_;
-    input_stream stream_;
-    unsigned width_;
-    unsigned height_;
-    int bit_depth_;
-    int color_type_;
-    bool has_alpha_;
-public:
-    explicit png_reader(std::string const& file_name);
-    png_reader(char const* data, std::size_t size);
-    ~png_reader();
-    unsigned width() const;
-    unsigned height() const;
-    inline bool has_alpha() const { return has_alpha_; }
-    bool premultiplied_alpha() const { return false; } //http://www.libpng.org/pub/png/spec/1.1/PNG-Rationale.html
-    void read(unsigned x,unsigned y, unsigned width, unsigned height, char * image);
-private:
-    void init();
-    static void png_read_data(png_structp png_ptr, png_bytep data, png_size_t length);
-};
-
-namespace
-{
-image_reader* create_png_reader(char const * data, std::size_t size)
-{
-    return new png_reader<boost::iostreams::array_source>(data, size);
-}
-
-const static bool registered = register_image_reader("png",create_png_reader);
-
-}
-
-
 void user_error_fn(png_structp /*png_ptr*/, png_const_charp error_msg)
 {
     throw image_reader_exception(std::string("failed to read invalid png: '") + error_msg + "'");
@@ -95,21 +40,6 @@ void png_reader<T>::png_read_data(png_structp png_ptr, png_bytep data, png_size_
 }
 
 template <typename T>
-png_reader<T>::png_reader(std::string const& file_name)
-    : source_(file_name,std::ios_base::in | std::ios_base::binary),
-      stream_(source_),
-      width_(0),
-      height_(0),
-      bit_depth_(0),
-      color_type_(0),
-      has_alpha_(false)
-{
-    if (!source_.is_open()) throw image_reader_exception("PNG reader: cannot open file '"+ file_name + "'");
-    if (!stream_) throw image_reader_exception("PNG reader: cannot open file '"+ file_name + "'");
-    init();
-}
-
-template <typename T>
 png_reader<T>::png_reader(char const* data, std::size_t size)
     : source_(data,size),
       stream_(source_),
@@ -263,4 +193,7 @@ void png_reader<T>::read(unsigned x0, unsigned y0, unsigned w, unsigned h, char
     }
     png_read_end(png_ptr,0);
 }
+
+template class png_reader<boost::iostreams::array_source>;
+
 }}
diff --git a/test/test.gyp b/test/test.gyp
index fecb6ed939..86dbcc08a5 100644
--- a/test/test.gyp
+++ b/test/test.gyp
@@ -163,7 +163,6 @@
       'type': 'executable',
       'sources': [
         './headless.cpp',
-        '../platform/default/png_reader.cpp',
         './fixtures/fixture_log.cpp',
       ],
       'conditions': [