feat(XMLFile.hpp): implement Buffer for XMLFile

Adamska1008 · Aug 31, 2024 · b4ab35a · b4ab35a
1 parent 17fd64c
commit b4ab35a
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Showing 4 changed files with 83 additions and 53 deletions.
diff --git a/include/myxml/buffer.hpp b/include/myxml/buffer.hpp
@@ -3,6 +3,7 @@
 #include <string>
 #include <string_view>
 #include <optional>
+#include <tuple>
 
 namespace myxml
 {
@@ -12,14 +13,19 @@ namespace myxml
      */
     class Buffer
     {
+    private:
+        std::size_t offset = 0;
+
+        virtual std::tuple<const char *, std::size_t> base() const = 0;
+
     public:
         virtual ~Buffer() = default;
-        virtual std::optional<char> Peek() const = 0;
-        virtual std::optional<std::string_view> PeekN(int) const = 0;
-        virtual std::optional<char> AfterN(int) const = 0;
-        virtual std::optional<std::string_view> AfterNM(int, int) const = 0;
-        virtual std::optional<char> Take() = 0;
-        virtual std::optional<std::string_view> TakeN(int) = 0;
+        virtual std::optional<char> Peek() const;
+        virtual std::optional<std::string_view> PeekN(int) const;
+        virtual std::optional<char> AfterN(int) const;
+        virtual std::optional<std::string_view> AfterNM(int, int) const;
+        virtual std::optional<char> Take();
+        virtual std::optional<std::string_view> TakeN(int);
     };
 
     class StringBuffer : public Buffer
@@ -28,18 +34,13 @@ namespace myxml
         using stringVariant = std::variant<std::string, std::string_view>;
 
         stringVariant inner;
-        std::size_t offset;
         std::string_view getView() const;
 
+        /** Implement Buffer */
+        virtual std::tuple<const char *, std::size_t> base() const override;
+
     public:
         StringBuffer(std::string_view);
         StringBuffer(std::string &&);
-
-        virtual std::optional<char> Peek() const override;
-        virtual std::optional<std::string_view> PeekN(int) const override;
-        virtual std::optional<char> AfterN(int) const override;
-        virtual std::optional<std::string_view> AfterNM(int, int) const override;
-        virtual std::optional<char> Take() override;
-        virtual std::optional<std::string_view> TakeN(int) override;
     };
 }
diff --git a/include/myxml/xmlfile.hpp b/include/myxml/xmlfile.hpp
@@ -1,16 +1,25 @@
 #pragma once
 #include <memory>
 #include <string_view>
+#include <optional>
+#include "myxml/buffer.hpp"
 
 namespace myxml
 {
-    class XMLFile
+    class XMLFile : public Buffer
     {
     private:
         XMLFile();
 
+        /* Mmap related*/
         int fd;
-        void *mappedRegion;
+        std::size_t fileSize;
+        char *inner;
+
+        std::size_t offset;
+
+        /* Implement Buffer*/
+        virtual std::tuple<const char *, std::size_t> base() const;
 
     public:
         static XMLFile Open(std::string_view fpath);

diff --git a/src/buffer.cpp b/src/buffer.cpp
@@ -2,78 +2,84 @@
 
 namespace myxml
 {
-    StringBuffer::StringBuffer(std::string_view inner)
-        : inner(inner), offset(0)
+    std::optional<char> Buffer::Peek() const
     {
-    }
-
-    StringBuffer::StringBuffer(std::string &&inner)
-        : inner(inner), offset(0)
-    {
-    }
-
-    std::optional<char> StringBuffer::Peek() const
-    {
-        auto view = this->getView();
-        if (offset >= view.length())
+        auto [ptr, len] = this->base();
+        if (this->offset >= len)
         {
             return std::nullopt;
         }
-        return view[this->offset];
+        return ptr[this->offset];
     }
 
-    std::optional<std::string_view> StringBuffer::PeekN(int n) const
+    std::optional<std::string_view> Buffer::PeekN(int n) const
     {
-        auto view = this->getView();
-        if (offset + n > view.length())
+        auto [ptr, len] = this->base();
+        if (this->offset >= len)
         {
             return std::nullopt;
         }
-        return view.substr(this->offset, n);
+        return std::string_view(ptr + this->offset, n);
     }
 
-    std::optional<char> StringBuffer::AfterN(int n) const
+    std::optional<char> Buffer::AfterN(int n) const
     {
-        auto view = this->getView();
-        if (offset + n > view.length())
+        auto [ptr, len] = this->base();
+        if (this->offset + n > len)
         {
             return std::nullopt;
         }
-        return view[this->offset + n];
+        return ptr[this->offset + n];
     }
 
-    std::optional<std::string_view> StringBuffer::AfterNM(int n, int m) const
+    std::optional<std::string_view> Buffer::AfterNM(int n, int m) const
     {
-        auto view = this->getView();
-        if (offset + n + m > view.length())
+        auto [ptr, len] = this->base();
+        if (this->offset + n + m > len)
         {
             return std::nullopt;
         }
-        return view.substr(offset + n, m);
+        return std::string_view(ptr + this->offset + n, m);
     }
 
-    std::optional<char> StringBuffer::Take()
+    std::optional<char> Buffer::Take()
     {
-        auto view = this->getView();
-        if (offset >= view.length())
+        auto [ptr, len] = this->base();
+        if (this->offset >= len)
         {
             return std::nullopt;
         }
-        return view[this->offset++];
+        return ptr[this->offset++];
     }
 
-    std::optional<std::string_view> StringBuffer::TakeN(int n)
+    std::optional<std::string_view> Buffer::TakeN(int n)
     {
-        auto view = this->getView();
-        if (offset + n >= view.length())
+        auto [ptr, len] = this->base();
+        if (offset + n >= len)
         {
             return std::nullopt;
         }
-        std::string_view it = view.substr(offset, n);
+        std::string_view it(ptr + this->offset, n);
         offset += n;
         return it;
     }
 
+    StringBuffer::StringBuffer(std::string_view inner)
+        : inner(inner)
+    {
+    }
+
+    StringBuffer::StringBuffer(std::string &&inner)
+        : inner(inner)
+    {
+    }
+
+    std::tuple<const char *, std::size_t> StringBuffer::base() const
+    {
+        auto view = this->getView();
+        return {view.data(), view.length()};
+    }
+
     std::string_view StringBuffer::getView() const
     {
         if (std::holds_alternative<std::string>(this->inner))

diff --git a/src/xmlfile.cpp b/src/xmlfile.cpp
@@ -10,6 +10,11 @@
 
 namespace myxml
 {
+    XMLFile::XMLFile()
+        : offset(0)
+    {
+    }
+
     XMLFile XMLFile::Open(std::string_view fpath)
     {
         XMLFile xfile;
@@ -23,15 +28,24 @@ namespace myxml
         {
             throw IOError();
         }
-        std::size_t fileSize = fileInfo.st_size;
-        xfile.mappedRegion = mmap(nullptr, fileSize, PROT_READ, MAP_PRIVATE, xfile.fd, 0);
-        if (xfile.mappedRegion == MAP_FAILED)
+        xfile.fileSize = fileInfo.st_size;
+        void *mappedRegion = mmap(nullptr, xfile.fileSize, PROT_READ, MAP_PRIVATE, xfile.fd, 0);
+        if (mappedRegion == MAP_FAILED)
         {
             throw IOError();
         }
+        xfile.inner = static_cast<char *>(mappedRegion);
+        return xfile;
     }
 
     XMLFile::~XMLFile()
     {
+        close(this->fd);
+        munmap(static_cast<void *>(this->inner), this->fileSize);
+    }
+
+    std::tuple<const char *, std::size_t> XMLFile::base() const
+    {
+        return {this->inner, this->fileSize};
     }
 }