Fix a typo in README
Start DeleteFileTest with clean plate

Summary:
Remove all the files from the test dir before the test. The test failed when there were some old files still in the directory, since it checks the file counts.
This is what caused jenkins' test failures. It was running fine on my machine so it was hard to repro.

Test Plan:
1. create an extra 000001.log file in the test directory
2. run a ./deletefile_test - test failes
3. patch ./deletefile_test with this
4. test succeeds

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14097
Fix typo.
Add an option to table_reader_bench to access the table from DB And Iterating non-existing prefix case.

Summary: This patch adds an option to table_reader_bench that queries run against DB level (which has one table). It is useful if user wants to see the extra costs DB level introduces.

Test Plan: Run the benchmark with and without the new parameter

Reviewers: haobo, dhruba, kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13863
Fixed typos
Added CONTRIBUTING.md
Merge pull request #5 from pborreli/typos

Fixed typos
Reformat CONTRIBUTING.md with less than 80 characters.
Make the options in table_builder/block_builder less misleading

Summary:
By original design, the regular `block options` and index `block options` in table_builder is mutable. We can use ChangeOptions to change the options directly.

However, with my last change, `BlockBuilder` no longer hold the reference to the index_block_options -- as a result, any changes made after the creation of index block builder will be of no effect.

But still the code is very error-prone and developers can easily fall into the trap without aware of it. To avoid this problem from happening in the future, I deleted the `ChangeOptions` and the `index_block_options`, as well as many other changes to make it less misleading.

Test Plan:
make
make check
make release

Reviewers: dhruba, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13707
make util/env_posix.cc work under mac

Summary: This diff invoves some more complicated issues in the posix environment.

Test Plan: works under mac os. will need to verify dev box.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14061
Change the logic in KeyMayExist()

Summary:
Previously in KeyMayExist(), if DB::Get() returns non-Status::OK(), we assumes key may not exist.
However, as if index block is not in block cache, Status::Incomplete() will return. Worse still, if
options::filter_delete is enabled, we may falsely ignore the "delete" operation:

  https://github.com/facebook/rocksdb/blob/master/db/write_batch.cc#L217-L220

This diff fixes this bug and will let crash-test pass.

Test Plan:
Ran:

  ./db_stress --test_batches_snapshots=1 --ops_per_thread=1000000 --threads=32 --write_buffer_size=4194304 --destroy_db_initially=1 --reopen=0 --readpercent=5 --prefixpercent=45 --writepercent=35 --delpercent=5 --iterpercent=10 --db=/home/kailiu/local/newer --max_key=100000000 --disable_seek_compaction=0 --mmap_read=0 --block_size=16384 --cache_size=1048576 --open_files=500000 --verify_checksum=1 --sync=0 --disable_wal=0 --disable_data_sync=0 --target_file_size_base=2097152
--target_file_size_multiplier=2 --max_write_buffer_number=3 --max_background_compactions=20 --max_bytes_for_level_base=10485760 --filter_deletes=1

Previously we'll see crash happens very soon.

Reviewers: igor, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14115
Upgrading compiler to gcc4.8.1

Summary:
Finally did it - the trick was in using --dynamic-linker option. This is first step to running ASAN.

All of our code seems to compile just fine on 4.8.1. However, I still left fbcode.471.sh in the 'build_tools/' just in case.

Test Plan: make clean; make

Reviewers: dhruba, haobo, kailiu, emayanke, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14109
Include <unistd.h> in db_test

Summary: This is the only compile issue in Ubuntu. It might be better to include <unistd.h> only in env_posix and add Truncate function to Env, but since we use truncate only in db_test, I don't think it makes much sense.

Test Plan: Rocksdb now compiles on Ubuntu!

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14127
Remove snappy from RocksDB distribution

Summary:
Argumentation here: https://github.com/facebook/rocksdb/issues/9

Even though we include snappy in the distribution, we do not link with it if we don't have snappy installed on the system.

Installing snappy is easy nowadays, just type:
sudo apt-get install libsnappy-dev

Test Plan: compile on ubuntu

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14133
Move back to gcc4.7.1

Summary: Dhruba can't compile on gcc4.8.1 so I'm moving temporarily back to 4.7.1 until we figure out what's wrong with 4.8. on his server.

Test Plan: It can compile on my devserver, but please 'arc patch' this diff and try compiling on your machine

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14139
Add License message to public header files.

Summary:
Add License message to public header files.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
Add a compilation guide to rocksdb

Summary: as title.

Test Plan: no

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14121
Move the compiler back to 4.8.1 + more small fixes

Summary:
1. Moved the compiler back to 4.8.1 and uses Centos 5.2 binaries if OS is Centos 5.2.

2. Fixes this issue: https://github.com/facebook/rocksdb/issues/7

3. We use lot of c++11 features, so we can't pretend we can compile without them. Makes it a first class dependency.

4. Fix blob_store_test, which failes on Ubuntu with "too many files opened" error

5. Removed dependency on port/port_chromium.h, which does not even exist on our system

Test Plan: make clean; make check

Reviewers: dhruba, kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14145
Compilation.md

Summary: Explained what it takes to compile it on linux.

Test Plan: -

Reviewers: dhruba, kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14151
[fbcode] Also add glibc and libgcc includes

Summary: We also need to use custom glibc and libgcc includes instead of system ones.

Test Plan:
'make clean; make check'.

Will also try on @dhruba's dev server.

Reviewers: dhruba, kailiu

Reviewed By: kailiu

CC: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D14157