From 652076614793f24bbd4f34cb8193269f6661486c Mon Sep 17 00:00:00 2001 From: Arun Subramaniyan Date: Sat, 28 Nov 2020 16:58:17 -0500 Subject: [PATCH] Fix segmentation fault when prefetching empty mapped overflow table --- SNAPLib/GenericFile_map.cpp | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/SNAPLib/GenericFile_map.cpp b/SNAPLib/GenericFile_map.cpp index 652e5b9..c789d24 100644 --- a/SNAPLib/GenericFile_map.cpp +++ b/SNAPLib/GenericFile_map.cpp @@ -29,6 +29,9 @@ Revision History: GenericFile_map *GenericFile_map::open(const char *filename) { size_t fileSize = QueryFileSize(filename); + if (0 == fileSize) { + return new GenericFile_map(NULL, NULL, 0); + } void *contents; MemoryMappedFile *mappedFile = OpenMemoryMappedFile(filename, 0, fileSize, &contents); @@ -58,7 +61,11 @@ GenericFile_map::~GenericFile_map() _int64 GenericFile_map::prefetch() { - AdviseMemoryMappedFilePrefetch(mappedFile); + if (NULL == mappedFile) { + return 0; + } + + AdviseMemoryMappedFilePrefetch(mappedFile); int pageSize = getpagesize(); _int64 total = 0;