Refactor `is::OffsetBuffer` to use `std::string_view` instead of `Buffer` simplifying code.

m-holger
1 parent 81cb7962
Showing 2 changed files with 14 additions and 12 deletions
libqpdf/BufferInputSource.cc
libqpdf/qpdf/InputSource_private.hh
@@ -151,7 +151,7 @@ is::OffsetBuffer::findAndSkipNextEOL_internal()
     if (cur_offset < 0) {
         throw std::logic_error("INTERNAL ERROR: is::OffsetBuffer offset < 0");
     }
-    qpdf_offset_t end_pos = max_offset;
+    auto end_pos = static_cast<qpdf_offset_t>(view_.size());
     if (cur_offset >= end_pos) {
         last_offset = end_pos + global_offset;
         cur_offset = end_pos;
@@ -159,9 +159,9 @@ is::OffsetBuffer::findAndSkipNextEOL_internal()
     }
     qpdf_offset_t result = 0;
-    unsigned char const* buffer = buf->getBuffer();
-    unsigned char const* end = buffer + end_pos;
-    unsigned char const* p = buffer + cur_offset;
+    auto buffer = view_.begin();
+    auto end = view_.end();
+    auto p = buffer + cur_offset;
     while (p < end && !(*p == '\r' || *p == '\n')) {
         ++p;
@@ -190,8 +190,8 @@ is::OffsetBuffer::seek_internal(qpdf_offset_t offset, int whence)
         break;
     case SEEK_END:
-        QIntC::range_check(max_offset, offset);
-        cur_offset = max_offset + offset;
+        QIntC::range_check(static_cast<qpdf_offset_t>(view_.size()), offset);
+        cur_offset = static_cast<qpdf_offset_t>(view_.size()) + offset;
         break;
     case SEEK_CUR:
@@ -215,7 +215,7 @@ is::OffsetBuffer::read(char* buffer, size_t length)
     if (cur_offset < 0) {
         throw std::logic_error("INTERNAL ERROR: is::OffsetBuffer offset < 0");
     }
-    qpdf_offset_t end_pos = max_offset;
+    auto end_pos = static_cast<qpdf_offset_t>(view_.size());
     if (cur_offset >= end_pos) {
         last_offset = end_pos + global_offset;
         return 0;
@@ -223,7 +223,7 @@ is::OffsetBuffer::read(char* buffer, size_t length)
     last_offset = cur_offset + global_offset;
     size_t len = std::min(QIntC::to_size(end_pos - cur_offset), length);
-    memcpy(buffer, buf->getBuffer() + cur_offset, len);
+    memcpy(buffer, view_.data() + cur_offset, len);
     cur_offset += QIntC::to_offset(len);
     return len;
 }
@@ -15,8 +15,11 @@ namespace qpdf::is
       public:
         OffsetBuffer(std::string const& description, Buffer* buf, qpdf_offset_t global_offset) :
             description(description),
-            buf(buf),
-            max_offset(buf ? static_cast<qpdf_offset_t>(buf->getSize()) : 0),
+            view_(
+                buf && buf->getSize()
+                    ? std::string_view(
+                          reinterpret_cast<const char*>(buf->getBuffer()), buf->getSize())
+                    : std::string_view()),
             global_offset(global_offset)
         {
             if (global_offset < 0) {
@@ -76,9 +79,8 @@ namespace qpdf::is
         void seek_internal(qpdf_offset_t offset, int whence);
         std::string description;
-        Buffer* buf;
         qpdf_offset_t cur_offset{0};
-        qpdf_offset_t max_offset;
+        std::string_view view_;
         qpdf_offset_t global_offset;
     };