Avoid using streams in ELFIO to massively reduce the binary size

source/elfio/elfio.hpp

@@ -24,8 +24,6 @@ THE SOFTWARE.
 #define ELFIO_HPP
 
 #include <string>
-#include <iostream>
-#include <fstream>
 #include <functional>
 #include <algorithm>
 #include <array>
@@ -131,37 +129,20 @@ class elfio
     }
 
     //------------------------------------------------------------------------------
-    bool load( const std::string& file_name, bool is_lazy = false )
+    bool load(const char * pBuffer, size_t pBufferSize)
-    {
-        pstream = std::make_unique<std::ifstream>();
-        pstream->open( file_name.c_str(), std::ios::in | std::ios::binary );
-        if ( pstream == nullptr || !*pstream ) {
-            return false;
-        }
-
-        bool ret = load( *pstream, is_lazy );
-
-        if ( !is_lazy ) {
-            pstream.release();
-        }
-
-        return ret;
-    }
-
-    //------------------------------------------------------------------------------
-    bool load( std::istream& stream, bool is_lazy = false )
     {
         sections_.clear();
         segments_.clear();
 
-        std::array<char, EI_NIDENT> e_ident = { 0 };
+        std::array<char, EI_NIDENT> e_ident = { };
         // Read ELF file signature
-        stream.seekg( 0 );
+        if(sizeof( e_ident ) > pBufferSize) {
-        stream.read( e_ident.data(), sizeof( e_ident ) );
+            return false;
+        }
+        memcpy( e_ident.data(), pBuffer, sizeof( e_ident ) );
 
         // Is it ELF file?
-        if ( stream.gcount() != sizeof( e_ident ) ||
+        if (e_ident[EI_MAG0] != ELFMAG0 || e_ident[EI_MAG1] != ELFMAG1 ||
-             e_ident[EI_MAG0] != ELFMAG0 || e_ident[EI_MAG1] != ELFMAG1 ||
             e_ident[EI_MAG2] != ELFMAG2 || e_ident[EI_MAG3] != ELFMAG3 ) {
             return false;
         }
@@ -181,12 +162,12 @@ class elfio
         if ( nullptr == header ) {
             return false;
         }
-        if ( !header->load( stream ) ) {
+        if ( !header->load( pBuffer, pBufferSize ) ) {
             return false;
         }
 
-        load_sections( stream, is_lazy );
+        load_sections( pBuffer, pBufferSize );
-        bool is_still_good = load_segments( stream, is_lazy );
+        bool is_still_good = load_segments( pBuffer, pBufferSize );
         return is_still_good;
     }
 
@@ -313,7 +294,7 @@ class elfio
     }
 
     //------------------------------------------------------------------------------
-    bool load_sections( std::istream& stream, bool is_lazy )
+    bool load_sections( const char * pBuffer, size_t pBufferSize )
     {
         unsigned char file_class = header->get_class();
         Elf_Half      entry_size = header->get_section_entry_size();
@@ -329,10 +310,9 @@ class elfio
 
         for ( Elf_Half i = 0; i < num; ++i ) {
             section* sec = create_section();
-            sec->load( stream,
+            sec->load( pBuffer, pBufferSize,
-                       static_cast<std::streamoff>( offset ) +
+                       static_cast<off_t>( offset ) +
-                           static_cast<std::streampos>( i ) * entry_size,
+                           static_cast<off_t>( i ) * entry_size);
-                       is_lazy );
             // To mark that the section is not permitted to reassign address
             // during layout calculation
             sec->set_address( sec->get_address() );
@@ -372,7 +352,7 @@ class elfio
     }
 
     //------------------------------------------------------------------------------
-    bool load_segments( std::istream& stream, bool is_lazy )
+    bool load_segments( const char * pBuffer, size_t pBufferSize )
     {
         unsigned char file_class = header->get_class();
         Elf_Half      entry_size = header->get_segment_entry_size();
@@ -404,11 +384,9 @@ class elfio
 
             segment* seg = segments_.back().get();
 
-            if ( !seg->load( stream,
+            if ( !seg->load( pBuffer, pBufferSize,
-                             static_cast<std::streamoff>( offset ) +
+                             static_cast<off_t>( offset ) +
-                                 static_cast<std::streampos>( i ) * entry_size,
+                                 static_cast<off_t>( i ) * entry_size)) {
-                             is_lazy ) ||
-                 stream.fail() ) {
                 segments_.pop_back();
                 return false;
             }
@@ -580,7 +558,6 @@ class elfio
 
     //------------------------------------------------------------------------------
   private:
-    std::unique_ptr<std::ifstream>         pstream = nullptr;
     std::unique_ptr<elf_header>            header  = nullptr;
     std::vector<std::unique_ptr<section>>  sections_;
     std::vector<std::unique_ptr<segment>>  segments_;

source/elfio/elfio_dump.hpp

@@ -25,8 +25,6 @@ THE SOFTWARE.
 
 #include <algorithm>
 #include <string>
-#include <ostream>
-#include <sstream>
 #include <iomanip>
 #include <elfio/elfio.hpp>
 

source/elfio/elfio_header.hpp

@@ -23,7 +23,7 @@ THE SOFTWARE.
 #ifndef ELF_HEADER_HPP
 #define ELF_HEADER_HPP
 
-#include <iostream>
+#include <cstring>
 
 namespace ELFIO {
 
@@ -32,7 +32,7 @@ class elf_header
   public:
     virtual ~elf_header() = default;
 
-    virtual bool load( std::istream& stream )       = 0;
+    virtual bool load( const char * pBuffer, size_t pBufferSize )       = 0;
 
     // ELF header functions
     ELFIO_GET_ACCESS_DECL( unsigned char, class );
@@ -98,12 +98,14 @@ template <class T> class elf_header_impl : public elf_header
     }
 
     //------------------------------------------------------------------------------
-    bool load( std::istream& stream ) override
+    bool load( const char * pBuffer, size_t pBufferSize ) override
     {
-        stream.seekg(0);
+        if(sizeof( header ) > pBufferSize) {
-        stream.read( reinterpret_cast<char*>( &header ), sizeof( header ) );
+            return false;
+        }
+        memcpy( reinterpret_cast<char*>( &header ), pBuffer, sizeof( header ));
 
-        return ( stream.gcount() == sizeof( header ) );
+        return true;
     }
 
     //------------------------------------------------------------------------------

source/elfio/elfio_section.hpp

@@ -24,7 +24,6 @@ THE SOFTWARE.
 #define ELFIO_SECTION_HPP
 
 #include <string>
-#include <iostream>
 #include <new>
 #include <limits>
 
@@ -58,16 +57,13 @@ class section
     virtual void
     insert_data( Elf_Xword pos, const char* raw_data, Elf_Word size )    = 0;
     virtual void   insert_data( Elf_Xword pos, const std::string& data ) = 0;
-    virtual size_t get_stream_size() const                               = 0;
-    virtual void   set_stream_size( size_t value )                       = 0;
 
   protected:
     ELFIO_SET_ACCESS_DECL( Elf64_Off, offset );
     ELFIO_SET_ACCESS_DECL( Elf_Half, index );
 
-    virtual bool load( std::istream&  stream,
+    virtual bool load( const char * pBuffer, size_t pBufferSize,
-                       std::streampos header_offset,
+                       off_t header_offset)               = 0;
-                       bool           is_lazy )               = 0;
     virtual bool is_address_initialized() const     = 0;
 };
 
@@ -118,9 +114,6 @@ template <class T> class section_impl : public section
     //------------------------------------------------------------------------------
     const char* get_data() const override
     {
-        if ( is_lazy ) {
-            load_data();
-        }
         return data.get();
     }
 
@@ -198,11 +191,6 @@ template <class T> class section_impl : public section
         return insert_data( pos, str_data.c_str(), (Elf_Word)str_data.size() );
     }
 
-    size_t get_stream_size() const override { return stream_size; }
-
-    //------------------------------------------------------------------------------
-    void set_stream_size( size_t value ) override { stream_size = value; }
-
     //------------------------------------------------------------------------------
   protected:
     //------------------------------------------------------------------------------
@@ -219,22 +207,19 @@ template <class T> class section_impl : public section
     }
 
     //------------------------------------------------------------------------------
-    bool load( std::istream&  stream,
+    bool load( const char * pBuffer, size_t pBufferSize,
-               std::streampos header_offset,
+               off_t header_offset) override
-               bool           is_lazy_ ) override
     {
-        pstream = &stream;
+        header  = { };
-        is_lazy = is_lazy_;
-        header  = { 0 };
 
-        stream.seekg( header_offset);
+        if( header_offset + sizeof( header ) > pBufferSize ) {
-        stream.read( reinterpret_cast<char*>( &header ), sizeof( header ) );
+            return false;
+        }
+        memcpy( reinterpret_cast<char*>( &header ), pBuffer + header_offset, sizeof( header ) );
 
-        if ( !is_lazy || is_compressed() ) {
+        bool ret = load_data(pBuffer, pBufferSize);
 
-            bool ret = load_data();
+        if (ret && is_compressed() ) {
-
-            if ( is_compressed() ) {
             Elf_Xword size              = get_size();
             Elf_Xword uncompressed_size = 0;
             auto      decompressed_data = compression->inflate(
@@ -248,24 +233,20 @@ template <class T> class section_impl : public section
         return ret;
     }
 
-        return true;
+    bool load_data(const char * pBuffer, size_t pBufferSize) const
-    }
-
-    bool load_data() const
     {
-        is_lazy        = false;
         Elf_Xword size = get_size();
         if ( nullptr == data && SHT_NULL != get_type() &&
-             SHT_NOBITS != get_type() && size < get_stream_size() ) {
+             SHT_NOBITS != get_type() && size < pBufferSize ) {
             data.reset( new ( std::nothrow ) char[size_t( size ) + 1] );
 
             if ( ( 0 != size ) && ( nullptr != data ) ) {
-                pstream->seekg(( *convertor )( header.sh_offset ));
+                auto offset = ( *convertor )( header.sh_offset );
-                pstream->read( data.get(), size );
+                if(offset + size > pBufferSize) {
-                if ( static_cast<Elf_Xword>( pstream->gcount() ) != size ) {
                     data = nullptr;
                     return false;
                 }
+                memcpy( data.get(), pBuffer + offset, size );
 
                 // refresh size because it may have changed if we had to decompress data
                 size = get_size();
@@ -287,7 +268,6 @@ template <class T> class section_impl : public section
 
     //------------------------------------------------------------------------------
   private:
-    mutable std::istream*                        pstream = nullptr;
     T                                            header  = {};
     Elf_Half                                     index   = 0;
     std::string                                  name;
@@ -296,8 +276,6 @@ template <class T> class section_impl : public section
     const endianess_convertor*                   convertor      = nullptr;
     const std::shared_ptr<compression_interface> compression    = nullptr;
     bool                                         is_address_set = false;
-    size_t                                       stream_size    = 0;
-    mutable bool                                 is_lazy        = false;
 };
 
 } // namespace ELFIO

source/elfio/elfio_segment.hpp

@@ -23,7 +23,6 @@ THE SOFTWARE.
 #ifndef ELFIO_SEGMENT_HPP
 #define ELFIO_SEGMENT_HPP
 
-#include <iostream>
 #include <vector>
 #include <new>
 #include <limits>
@@ -62,9 +61,8 @@ class segment
 
     virtual const std::vector<Elf_Half>& get_sections() const = 0;
 
-    virtual bool load( std::istream&  stream,
+    virtual bool load( const char * pBuffer, size_t pBufferSize,
-                       std::streampos header_offset,
+                       off_t header_offset )               = 0;
-                       bool           is_lazy )               = 0;
 };
 
 //------------------------------------------------------------------------------
@@ -94,9 +92,6 @@ template <class T> class segment_impl : public segment
     //------------------------------------------------------------------------------
     const char* get_data() const override
     {
-        if ( is_lazy ) {
-            load_data();
-        }
         return data.get();
     }
 
@@ -159,43 +154,35 @@ template <class T> class segment_impl : public segment
     void set_index( const Elf_Half& value ) override { index = value; }
 
     //------------------------------------------------------------------------------
-    bool load( std::istream&  stream,
+    bool load( const char * pBuffer, size_t pBufferSize,
-               std::streampos header_offset,
+               off_t header_offset) override
-               bool           is_lazy_ ) override
     {
-        pstream = &stream;
+        if( header_offset + sizeof( ph ) > pBufferSize ) {
-        is_lazy = is_lazy_;
+            return false;
-
+        }
-        stream.seekg( header_offset);
+        memcpy( reinterpret_cast<char*>( &ph ), pBuffer + header_offset, sizeof( ph ) );
-        stream.read( reinterpret_cast<char*>( &ph ), sizeof( ph ) );
         is_offset_set = true;
 
-        if ( !is_lazy ) {
+        return load_data(pBuffer, pBufferSize);
-            return load_data();
-        }
-
-        return true;
     }
 
     //------------------------------------------------------------------------------
-    bool load_data() const
+    bool load_data(const char * pBuffer, size_t pBufferSize) const
     {
-        is_lazy = false;
         if ( PT_NULL == get_type() || 0 == get_file_size() ) {
             return true;
         }
-
+        auto offset = ( *convertor )( ph.p_offset );
-        pstream->seekg(( *convertor )( ph.p_offset ));
         Elf_Xword size = get_file_size();
 
-        if ( size > get_stream_size() ) {
+        if ( size > pBufferSize ) {
             data = nullptr;
         }
         else {
             data.reset( new ( std::nothrow ) char[(size_t)size + 1] );
 
-            if ( nullptr != data.get() && pstream->read( data.get(), size ) ) {
+            if ( nullptr != data.get()) {
-                data.get()[size] = 0;
+                memcpy(data.get(), pBuffer + offset, size);
             }
             else {
                 data = nullptr;
@@ -206,23 +193,14 @@ template <class T> class segment_impl : public segment
         return true;
     }
 
-    //------------------------------------------------------------------------------
-    size_t get_stream_size() const { return stream_size; }
-
-    //------------------------------------------------------------------------------
-    void set_stream_size( size_t value ) { stream_size = value; }
-
     //------------------------------------------------------------------------------
   private:
-    mutable std::istream*           pstream = nullptr;
     T                               ph      = {};
     Elf_Half                        index   = 0;
     mutable std::unique_ptr<char[]> data;
     std::vector<Elf_Half>           sections;
     const endianess_convertor*      convertor     = nullptr;
-    size_t                          stream_size   = 0;
     bool                            is_offset_set = false;
-    mutable bool                    is_lazy       = false;
 };
 
 } // namespace ELFIO

source/elfio/elfio_symbols.hpp

@@ -54,8 +54,7 @@ template <class S> class symbol_section_accessor_template
             return nRet;
         }
 
-        if ( symbol_section->get_entry_size() >= minimum_symbol_size &&
+        if ( symbol_section->get_entry_size() >= minimum_symbol_size ) {
-             symbol_section->get_size() <= symbol_section->get_stream_size() ) {
             nRet =
                 symbol_section->get_size() / symbol_section->get_entry_size();
         }

source/elfio/elfio_utils.hpp

@@ -24,7 +24,6 @@ THE SOFTWARE.
 #define ELFIO_UTILS_HPP
 
 #include <cstdint>
-#include <ostream>
 
 #define ELFIO_GET_ACCESS_DECL( TYPE, NAME ) virtual TYPE get_##NAME() const = 0
 

source/plugin/PluginInformationFactory.cpp

@@ -18,7 +18,6 @@
 #include "PluginInformationFactory.h"
 #include "../utils/ElfUtils.h"
 #include "../utils/utils.h"
-#include "utils/membuf.hpp"
 #include "utils/wiiu_zlib.hpp"
 #include <coreinit/cache.h>
 #include <map>
@@ -36,10 +35,8 @@ PluginInformationFactory::load(const std::shared_ptr<PluginData> &pluginData, re
         return {};
     }
     elfio reader(new wiiu_zlib);
-    membuf sbuf((char *) pluginData->buffer.get(), (char *) pluginData->buffer.get() + pluginData->length);
-    std::istream in(&sbuf);
 
-    if (!reader.load(in)) {
+    if (!reader.load(reinterpret_cast<const char *>(pluginData->buffer.get()), pluginData->length)) {
         DEBUG_FUNCTION_LINE_ERR("Can't process PluginData in elfio");
         return {};
     }

source/plugin/PluginMetaInformationFactory.cpp

@@ -19,7 +19,6 @@
 #include "elfio/elfio.hpp"
 #include "fs/FSUtils.h"
 #include "utils/logger.h"
-#include "utils/membuf.hpp"
 #include "utils/wiiu_zlib.hpp"
 #include <memory>
 
@@ -29,9 +28,7 @@ std::optional<std::unique_ptr<PluginMetaInformation>> PluginMetaInformationFacto
         return {};
     }
     ELFIO::elfio reader(new wiiu_zlib);
-    membuf sbuf((char *) pluginData->buffer.get(), (char *) pluginData->buffer.get() + pluginData->length);
+    if (!reader.load(reinterpret_cast<const char *>(pluginData->buffer.get()), pluginData->length)) {
-    std::istream in(&sbuf);
-    if (!reader.load(in)) {
         DEBUG_FUNCTION_LINE_ERR("Can't process PluginData in elfio");
         return {};
     }
@@ -48,10 +45,7 @@ std::optional<std::unique_ptr<PluginMetaInformation>> PluginMetaInformationFacto
         return {};
     }
 
-    membuf sbuf((char *) buffer, (char *) buffer + length);
+    if (!reader.load(reinterpret_cast<const char *>(buffer), length)) {
-    std::istream in(&sbuf);
-
-    if (!reader.load(in)) {
         DEBUG_FUNCTION_LINE_ERR("Can't process PluginData in elfio");
         return {};
     }
@@ -63,10 +57,7 @@ std::optional<std::unique_ptr<PluginMetaInformation>> PluginMetaInformationFacto
 std::optional<std::unique_ptr<PluginMetaInformation>> PluginMetaInformationFactory::loadPlugin(char *buffer, size_t size) {
     ELFIO::elfio reader(new wiiu_zlib);
 
-    membuf sbuf((char *) buffer, (char *) buffer + size);
+    if (!reader.load(reinterpret_cast<const char *>(buffer), size)) {
-    std::istream in(&sbuf);
-
-    if (!reader.load(in)) {
         DEBUG_FUNCTION_LINE_ERR("Can't find or process ELF file");
         return std::nullopt;
     }

source/utils/membuf.hpp

@@ -1,23 +0,0 @@
-#pragma once
-
-#include <iostream>
-
-struct membuf : std::streambuf {
-    membuf(char *begin, char *end) {
-        this->setg(begin, begin, end);
-    }
-
-    pos_type seekoff(off_type off, std::ios_base::seekdir dir, std::ios_base::openmode which = std::ios_base::in) override {
-        if (dir == std::ios_base::cur)
-            gbump(off);
-        else if (dir == std::ios_base::end)
-            setg(eback(), egptr() + off, egptr());
-        else if (dir == std::ios_base::beg)
-            setg(eback(), eback() + off, egptr());
-        return gptr() - eback();
-    }
-
-    pos_type seekpos(pos_type sp, std::ios_base::openmode which) override {
-        return seekoff(sp - pos_type(off_type(0)), std::ios_base::beg, which);
-    }
-};

source/utils/wiiu_zlib.hpp

@@ -34,7 +34,7 @@ public:
         }
 
         int z_ret;
-        z_stream s = {nullptr};
+        z_stream s = {};
 
         s.zalloc = Z_NULL;
         s.zfree  = Z_NULL;
@@ -66,8 +66,8 @@ public:
             return nullptr;
         }
 
-        int z_ret  = 0;
+        int z_ret;
-        z_stream s = {nullptr};
+        z_stream s = {};
 
         s.zalloc = Z_NULL;
         s.zfree  = Z_NULL;