Fix CString reader in BufferSliceExtensions

SynaptiveMedical · Dec 20, 2022 · d095f84 · d095f84
1 parent 4a46bf3
commit d095f84
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Showing 2 changed files with 30 additions and 8 deletions.
diff --git a/LiteDB/Engine/FileReader/FileReaderV8.cs b/LiteDB/Engine/FileReader/FileReaderV8.cs
@@ -95,6 +95,33 @@ private void LoadPragmas()
             }
         }
 
+        /// <summary>
+        /// Read all file (and log) to find all data pages (and store groupby colPageID)
+        /// </summary>
+        private void LoadDataPages()
+        {
+            var header = ReadPage(0, out _, out _);
+
+            var lastPageID = header.Buffer.ReadUInt32(HeaderPage.P_LAST_PAGE_ID);
+
+            for (uint i = 0; i < lastPageID; i++)
+            {
+                var page = ReadPage(i, out _, out _);
+
+                if (page.PageType == PageType.Data)
+                {
+                    if (_collectionsDataPages.TryGetValue(page.ColID, out var list))
+                    {
+                        list.Add(page.PageID);
+                    }
+                    else
+                    {
+                        _collectionsDataPages[page.ColID] = new List<uint> { page.PageID };
+                    }
+                }
+            }
+        }
+
         /// <summary>
         /// Load all collections from header OR via all data-pages ColID
         /// </summary>

diff --git a/LiteDB/Utils/Extensions/BufferSliceExtensions.cs b/LiteDB/Utils/Extensions/BufferSliceExtensions.cs
@@ -105,21 +105,16 @@ public static string ReadCString(this BufferSlice buffer, int offset, out int le
         {
             length = buffer.Count - buffer.Offset - offset;
 
-            var i = offset;
-
-            for (; i < buffer.Count; i++)
+            for (var i = offset + buffer.Offset; i < buffer.Count; i++)
             {
                 if (buffer[i] == '\0')
                 {
-                    length = i - offset + 1; // +1 for \0
+                    length = i - buffer.Offset - offset + 1; // +1 for \0
                     break;
                 }
             }
 
-            // exclude \0 is last char is \0
-            var readLength = buffer[i] == '\0' ? length - 1 : length;
-
-            return Encoding.UTF8.GetString(buffer.Array, buffer.Offset + offset, readLength);
+            return Encoding.UTF8.GetString(buffer.Array, buffer.Offset + offset, length);
         }
 
         /// <summary>