tree c0a00b9b4d52ff3dfeb50f5d894bad2d71389b00
parent 294421ca6ac449cd9279aaabc63cb4bb080acca3
author Tim Barron <tjbarron@google.com> 1626211786 +0000
committer Tim Barron <tjbarron@google.com> 1626890988 +0000

Switch to PWrite to grow underlying file in FileBackedVector.

Modify file-backed-vector to 1) include a check that the size of the
file is greater than or equal to the number of elements *
sizeof(element) and 2) use PWrite to force the system to allocate disk
blocks so that we avoid the risk of trying to mmap a region of the file
that the system hasn't allocated a block for (and is unable to do so).

Bug: 191444782
Test: framework presubmit
Test: manually copied change to google3 and ran all icing lib c++ tests
Test: Unit tests added to FileBackedVectorTest
Change-Id: I1134df4becf246e0a9e170b80ee62c37383f8d7b