From 55de873f660b725470340ad737aec1340fcf6a26 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9bastien=20Rombauts?= <sebastien.rombauts@gmail.com>
Date: Sat, 4 Jan 2020 18:54:27 +0100
Subject: [PATCH] Fix Database::getHeaderInfo() for case where the file is not
 even 100 bytes long

---
 src/Database.cpp | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/src/Database.cpp b/src/Database.cpp
index 5f6f5b4..48248a1 100644
--- a/src/Database.cpp
+++ b/src/Database.cpp
@@ -287,28 +287,32 @@ Header Database::getHeaderInfo(const std::string& aFilename)
 
     if (aFilename.empty())
     {
-        throw SQLite::Exception("Could not open database, the aFilename parameter was empty.");
+        throw SQLite::Exception("Filename parameter is empty");
     }
 
-    std::ifstream fileBuffer(aFilename.c_str(), std::ios::in | std::ios::binary);
-
-    if (fileBuffer.is_open())
     {
-        fileBuffer.seekg(0, std::ios::beg);
-        fileBuffer.read(pBuf, 100);
-        fileBuffer.close();
-        strncpy(pHeaderStr, pBuf, 16);
-    }
-
-    else
-    {
-        throw SQLite::Exception("Error opening file: " + aFilename);
+        std::ifstream fileBuffer(aFilename.c_str(), std::ios::in | std::ios::binary);
+        if (fileBuffer.is_open())
+        {
+            fileBuffer.seekg(0, std::ios::beg);
+            fileBuffer.read(pBuf, 100);
+            fileBuffer.close();
+            if (fileBuffer.gcount() < 100)
+            {
+                throw SQLite::Exception("File " + aFilename + " is too short");
+            }
+        }
+        else
+        {
+            throw SQLite::Exception("Error opening file " + aFilename);
+        }
     }
 
     // If the "magic string" can't be found then header is invalid, corrupt or unreadable
+    strncpy(pHeaderStr, pBuf, 16);
     if (!strncmp(pHeaderStr, "SQLite format 3", 15) == 0)
     {
-        throw SQLite::Exception("Invalid or encrypted SQLite header");
+        throw SQLite::Exception("Invalid or encrypted SQLite header in file " + aFilename);
     }
 
     h.pageSizeBytes = (buf[16] << 8) | buf[17];