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# Compile-time options passed to SQLite when compiling and building
# the Chromium amalgamations.
sqlite_common_configuration_flags = [
"SQLITE_ENABLE_FTS3",
# New unicode61 tokenizer with built-in tables.
"SQLITE_DISABLE_FTS3_UNICODE",
# Chrome does not enable fts4, disable extra code.
"SQLITE_DISABLE_FTS4_DEFERRED",
"SQLITE_ENABLE_ICU",
# Defaults the secure_delete pragma to 1.
#
# This causes SQLite to overwrite all deleted information with zeroes,
# trading additional I/O for better privacy guarantees.
"SQLITE_SECURE_DELETE",
# TODO(pwnall): SQLite adds mutexes to protect structures which cross
# threads. In theory Chrome should be able to turn this to "2" which
# should give a slight speed boost. "2" is safe as long as a single
# connection is not used by more than one thread at a time.
"SQLITE_THREADSAFE=1",
# SQLite can spawn threads to sort in parallel if configured
# appropriately. Chrome doesn't configure SQLite for that, and would
# prefer to control distribution to worker threads.
"SQLITE_MAX_WORKER_THREADS=0",
# Allow 256MB mmap footprint per connection. Should not be too open-ended
# as that could cause memory fragmentation. 50MB encompasses the 99th
# percentile of Chrome databases in the wild.
# TODO(pwnall): A 64-bit-specific value could be 1G or more.
# TODO(pwnall): Figure out if exceeding this is costly.
"SQLITE_MAX_MMAP_SIZE=268435456",
# The default POSIX permissions for a newly created SQLite database.
#
# If unspecified, this defaults to 0644. All the data stored by Chrome is
# private, so our databases use stricter settings.
"SQLITE_DEFAULT_FILE_PERMISSIONS=0600",
# Databases are opened in EXCLUSIVE mode by default.
#
# NORMAL mode, where a database can be used by multiple processes
# simultaneously, can be enabled by executing "PRAGMA locking_mode=0".
#
# https://www.sqlite.org/compile.html#default_locking_mode
# https://www.sqlite.org/pragma.html#pragma_locking_mode
"SQLITE_DEFAULT_LOCKING_MODE=1",
# Needed by the SQL MemoryDumpProvider.
#
# Setting this to 1 is needed to collect the information reported by
# sqlite3_status64(SQLITE_STATUS_MEMORY_USED). Without this setting, the API
# still exists, but does not work as promised.
"SQLITE_DEFAULT_MEMSTATUS=1",
# Must match sql::Database::kDefaultPageSize.
"SQLITE_DEFAULT_PAGE_SIZE=4096",
# By default SQLite pre-allocates 100 pages of pcache data, which will not
# be released until the handle is closed. This is contrary to Chrome's
# memory-usage goals.
"SQLITE_DEFAULT_PCACHE_INITSZ=0",
# The flags below are recommended in the SQLite documentation.
"SQLITE_LIKE_DOESNT_MATCH_BLOBS",
"SQLITE_OMIT_DEPRECATED",
"SQLITE_OMIT_PROGRESS_CALLBACK",
"SQLITE_OMIT_SHARED_CACHE",
"SQLITE_USE_ALLOCA",
# Chrome does not use sqlite3_column_decltype().
"SQLITE_OMIT_DECLTYPE",
# Chrome does not use SQLite's JSON support.
"SQLITE_OMIT_JSON",
# Chrome does not use sqlite3_{enable_}load_extension().
# Asides from giving us fairly minor code savings, this option disables code
# that breaks our method for renaming SQLite's exported symbols. Last,
# there's a tiny security benefit to knowing that WebSQL can't possibly
# reach extension loading code.
"SQLITE_OMIT_LOAD_EXTENSION",
# Uses isnan() in the C99 standard library.
"SQLITE_HAVE_ISNAN",
# Chrome uses SQLite's built-in corruption recovery module.
# See https://www.sqlite.org/recovery.html
# Use of this module requires compiling a separate "sqlite3r.c" target, which
# generates "sqlite3r.c" and "sqlite3r.h", versions of the amalgamation files
# that include the recover extension. We then map this back to "sqlite3.h"
# when generating amalgamations to hide this detail from the rest of the
# platform. If this changes, or if we ever remove this flag, we would need to
# update the mapping in scripts/generate_amalgamation.py.
"SQLITE_HAVE_SQLITE3R",
]
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