std::function conversions

Signed-off-by: Rosen Penev <rosenp@gmail.com>

app/actions.cpp

@@ -331,8 +331,8 @@ int Print::printTag(const Exiv2::ExifData& exifData, const std::string& key, con
   return rc;
 }  // Print::printTag
 
-int Print::printTag(const Exiv2::ExifData& exifData, EasyAccessFct easyAccessFct, const std::string& label,
+int Print::printTag(const Exiv2::ExifData& exifData, const EasyAccessFct& easyAccessFct, const std::string& label,
-                    EasyAccessFct easyAccessFctFallback) const {
+                    const EasyAccessFct& easyAccessFctFallback) const {
   int rc = 0;
   if (!label.empty()) {
     printLabel(label);

app/actions.hpp

@@ -155,14 +155,14 @@ class Print : public Task {
    */
   int printTag(const Exiv2::ExifData& exifData, const std::string& key, const std::string& label = "") const;
   //! Type for an Exiv2 Easy access function
-  using EasyAccessFct = Exiv2::ExifData::const_iterator (*)(const Exiv2::ExifData& ed);
+  using EasyAccessFct = std::function<Exiv2::ExifData::const_iterator(const Exiv2::ExifData& ed)>;
   /*!
     @brief Print one summary line with a label (if provided) and requested
            data. A line break is printed only if a label is provided.
     @return 1 if a line was written, 0 if the information was not found.
    */
-  int printTag(const Exiv2::ExifData& exifData, EasyAccessFct easyAccessFct, const std::string& label = "",
+  int printTag(const Exiv2::ExifData& exifData, const EasyAccessFct& easyAccessFct, const std::string& label = "",
-               EasyAccessFct easyAccessFctFallback = nullptr) const;
+               const EasyAccessFct& easyAccessFctFallback = nullptr) const;
 
  private:
   std::string path_;

samples/easyaccess-test.cpp

@@ -5,14 +5,11 @@
 #include <iomanip>
 #include <iostream>
 
-using EasyAccessFct = Exiv2::ExifData::const_iterator (*)(const Exiv2::ExifData&);
+using EasyAccessFct = std::function<Exiv2::ExifData::const_iterator(const Exiv2::ExifData&)>;
+using EasyAccess = std::pair<const char*, EasyAccessFct>;
 
-struct EasyAccess {
+static const EasyAccess easyAccess[] = {
-  const char* label_;
+    {"Orientation", Exiv2::orientation},
-  EasyAccessFct findFct_;
-};
-
-static const EasyAccess easyAccess[] = {{"Orientation", Exiv2::orientation},
     {"ISO speed", Exiv2::isoSpeed},
     {"Date & time original", Exiv2::dateTimeOriginal},
     {"Flash bias", Exiv2::flashBias},
@@ -45,7 +42,8 @@ static const EasyAccess easyAccess[] = {{"Orientation", Exiv2::orientation},
     {"Flash energy", Exiv2::flashEnergy},
     {"Exposure index", Exiv2::exposureIndex},
     {"Sensing method", Exiv2::sensingMethod},
-                                        {"AF point", Exiv2::afPoint}};
+    {"AF point", Exiv2::afPoint},
+};
 
 int main(int argc, char** argv) {
   try {
@@ -64,9 +62,9 @@ int main(int argc, char** argv) {
     image->readMetadata();
     Exiv2::ExifData& ed = image->exifData();
 
-    for (auto&& ea : easyAccess) {
+    for (auto&& [label, fct] : easyAccess) {
-      auto pos = ea.findFct_(ed);
+      auto pos = fct(ed);
-      std::cout << std::setw(21) << std::left << ea.label_;
+      std::cout << std::setw(21) << std::left << label;
       if (pos != ed.end()) {
         std::cout << " (" << std::setw(35) << pos->key() << ") : " << pos->print(&ed) << "\n";
       } else {

src/makernote_int.hpp

@@ -8,6 +8,8 @@
 #include "tags_int.hpp"
 #include "types.hpp"
 
+#include <functional>
+
 // namespace extensions
 namespace Exiv2::Internal {
 class IoWrapper;
@@ -28,11 +30,10 @@ std::string readExiv2Config(const std::string& section, const std::string& value
 // class definitions
 
 //! Type for a pointer to a function creating a makernote (image)
-using NewMnFct = TiffComponent* (*)(uint16_t tag, IfdId group, IfdId mnGroup, const byte* pData, size_t size,
+using NewMnFct = std::function<TiffComponent*(uint16_t, IfdId, IfdId, const byte*, size_t, ByteOrder)>;
-                                    ByteOrder byteOrder);
 
 //! Type for a pointer to a function creating a makernote (group)
-using NewMnFct2 = TiffComponent* (*)(uint16_t tag, IfdId group, IfdId mnGroup);
+using NewMnFct2 = std::function<TiffComponent*(uint16_t tag, IfdId group, IfdId mnGroup)>;
 
 //! Makernote registry structure
 struct TiffMnRegistry {

src/tiffcomposite_int.hpp

@@ -1240,10 +1240,10 @@ class TiffIfdMakernote : public TiffComponent {
   @brief Function pointer type for a function to determine which cfg + def
          of a corresponding array set to use.
  */
-using CfgSelFct = int (*)(uint16_t, const byte*, size_t, TiffComponent* const);
+using CfgSelFct = int (*)(uint16_t, const byte*, size_t, TiffComponent*);
 
 //! Function pointer type for a crypt function used for binary arrays.
-using CryptFct = DataBuf (*)(uint16_t, const byte*, size_t, TiffComponent* const);
+using CryptFct = DataBuf (*)(uint16_t, const byte*, size_t, TiffComponent*);
 
 //! Defines one tag in a binary array
 struct ArrayDef {

src/tifffwd_int.hpp

@@ -9,6 +9,7 @@
 #include "types.hpp"
 
 // + standard includes
+#include <functional>
 #include <stack>
 
 // *****************************************************************************
@@ -61,17 +62,17 @@ using EncoderFct = void (TiffEncoder::*)(TiffEntryBase*, const Exifdatum*);
 /*!
   @brief Type for a function pointer for a function to decode a TIFF component.
  */
-using FindDecoderFct = DecoderFct (*)(const std::string& make, uint32_t extendedTag, IfdId group);
+using FindDecoderFct = std::function<DecoderFct(const std::string& make, uint32_t extendedTag, IfdId group)>;
 /*!
   @brief Type for a function pointer for a function to encode a TIFF component.
  */
-using FindEncoderFct = EncoderFct (*)(const std::string& make, uint32_t extendedTag, IfdId group);
+using FindEncoderFct = std::function<EncoderFct(const std::string& make, uint32_t extendedTag, IfdId group)>;
 /*!
   @brief Type for a function pointer for a function to create a TIFF component.
          Use TiffComponent::UniquePtr, it is not used in this declaration only
          to reduce dependencies.
  */
-using NewTiffCompFct = std::unique_ptr<TiffComponent> (*)(uint16_t tag, IfdId group);
+using NewTiffCompFct = std::function<std::unique_ptr<TiffComponent>(uint16_t tag, IfdId group)>;
 
 //! Stack to hold a path from the TIFF root element to a TIFF entry
 using TiffPath = std::stack<TiffPathItem>;

src/tiffimage_int.cpp

@@ -1848,7 +1848,7 @@ ByteOrder TiffParserWorker::decode(ExifData& exifData, IptcData& iptcData, XmpDa
 
   auto rootDir = parse(pData, size, root, pHeader);
   if (rootDir) {
-    TiffDecoder decoder(exifData, iptcData, xmpData, rootDir.get(), findDecoderFct);
+    TiffDecoder decoder(exifData, iptcData, xmpData, rootDir.get(), std::move(findDecoderFct));
     rootDir->accept(decoder);
   }
   return pHeader->byteOrder();
@@ -1857,7 +1857,7 @@ ByteOrder TiffParserWorker::decode(ExifData& exifData, IptcData& iptcData, XmpDa
 
 WriteMethod TiffParserWorker::encode(BasicIo& io, const byte* pData, size_t size, const ExifData& exifData,
                                      const IptcData& iptcData, const XmpData& xmpData, uint32_t root,
-                                     FindEncoderFct findEncoderFct, TiffHeaderBase* pHeader,
+                                     const FindEncoderFct& findEncoderFct, TiffHeaderBase* pHeader,
                                      OffsetWriter* pOffsetWriter) {
   /*
      1) parse the binary image, if one is provided, and

src/tiffimage_int.hpp

@@ -263,7 +263,7 @@ class TiffParserWorker {
    */
   static WriteMethod encode(BasicIo& io, const byte* pData, size_t size, const ExifData& exifData,
                             const IptcData& iptcData, const XmpData& xmpData, uint32_t root,
-                            FindEncoderFct findEncoderFct, TiffHeaderBase* pHeader, OffsetWriter* pOffsetWriter);
+                            const FindEncoderFct& findEncoderFct, TiffHeaderBase* pHeader, OffsetWriter* pOffsetWriter);
 
  private:
   /*!

src/tiffvisitor_int.cpp

@@ -193,7 +193,7 @@ TiffDecoder::TiffDecoder(ExifData& exifData, IptcData& iptcData, XmpData& xmpDat
     iptcData_(iptcData),
     xmpData_(xmpData),
     pRoot_(pRoot),
-    findDecoderFct_(findDecoderFct),
+    findDecoderFct_(std::move(findDecoderFct)),
     decodedIptc_(false) {
   // #1402 Fujifilm RAF. Search for the make
   // Find camera make in existing metadata (read from the JPEG)
@@ -460,7 +460,7 @@ TiffEncoder::TiffEncoder(ExifData exifData, const IptcData& iptcData, const XmpD
     isNewImage_(isNewImage),
     pPrimaryGroups_(pPrimaryGroups),
     pSourceTree_(nullptr),
-    findEncoderFct_(findEncoderFct),
+    findEncoderFct_(std::move(findEncoderFct)),
     dirty_(false),
     writeMethod_(wmNonIntrusive) {
   byteOrder_ = pHeader->byteOrder();