simplify image_readers creation implementation

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

3 files changed, 22 insertions, 156 deletions

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>;
+
 }}