Since that has a fixed hash table size and doesn't support delete, we can't
do a thorough comparison, but we can insert and search.

Also general cleanups:
(1) Don't assume that strings are folded by the compiler.
(2) Implement likely_stats_reset().
(3) Return non-const string from likely_stats(), as caller must free it.
(4) Don't use struct info indirection (that was from when we used callbacks?)
(5) Close memory leak in run-debug.c

Unfortunately it's a bit of a pain to use for typed hashtables, but it
works.

We change from htable_new()/htable_free() to htable_init/htable_clear.
We also change HTABLE_DEFINE_TYPE() to be the full name, without automatically
prepending htable_.

There's no real reason to start with 128 entries.

This lets us compare hash table vs. strset vs. the example
implementation of critbit trees.

cbspeed 100 runs, min-max(avg):
#01: Initial insert:   236-245(237)
#02: Initial lookup (match):   180-186(180)
#03: Initial lookup (miss):   171-185(172)
#04: Initial lookup (random):   441-457(444)
#05: Initial delete all:   127-132(128)
#06: Initial re-inserting:   219-225(220)
#07: Deleting first half:   101-104(102)
#08: Adding (a different) half:   158-162(159)
#09: Lookup after half-change (match):   202-207(203)
#10: Lookup after half-change (miss):   217-222(218)
#11: Churn 1:   297-302(299)
#12: Churn 2:   297-305(300)
#13: Churn 3:   301-308(303)
#14: Post-Churn lookup (match):   189-195(190)
#15: Post-Churn lookup (miss):   189-193(190)
#16: Post-Churn lookup (random):   499-513(503)

speed 100 runs, min-max(avg):
#01: Initial insert:   211-218(212)
#02: Initial lookup (match):   161-166(162)
#03: Initial lookup (miss):   157-162(158)
#04: Initial lookup (random):   452-460(454)
#05: Initial delete all:   126-135(127)
#06: Initial re-inserting:   193-201(194)
#07: Deleting first half:   99-107(99)
#08: Adding (a different) half:   143-190(144)
#09: Lookup after half-change (match):   183-195(184)
#10: Lookup after half-change (miss):   197-203(198)
#11: Churn 1:   271-278(274)
#12: Churn 2:   280-287(282)
#13: Churn 3:   277-285(279)
#14: Post-Churn lookup (match):   171-175(171)
#15: Post-Churn lookup (miss):   174-178(175)
#16: Post-Churn lookup (random):   525-552(528)

stringspeed 100 runs, min-max(avg):
#01: Initial insert:   300-343(308)
#02: Initial lookup (match):   98-136(99)
#03: Initial lookup (miss):   73-102(75)
#04: Initial lookup (random):   230-282(233)
#05: Initial delete all:   66-102(69)
#06: Initial re-inserting:   62-99(64)
#07: Deleting first half:   43-52(43)
#08: Adding (a different) half:   101-156(106)
#09: Lookup after half-change (match):   114-156(120)
#10: Lookup after half-change (miss):   94-103(95)
#11: Churn 1:   98-105(99)
#12: Churn 2:   96-104(98)
#13: Churn 3:   174-184(176)
#14: Post-Churn lookup (match):   93-112(94)
#15: Post-Churn lookup (miss):   77-107(79)
#16: Post-Churn lookup (random):   229-265(232)

Not as fast as using htable, but simple and provides order and prefix
ops.

Firstly, -Wwrite-strings makes string literals const, secondly, we mustn't
define str_strstr etc in terms of themselves!

LGPL is overkill for trivial wrappers like this.

Note where previous analysis said the code was outside a function, and
fix double new-line.  Also, treat end of comment as end of statement.

This handles both pointer and integer types using ccan/tcon.

It's now a completely generic set implementation, and uses ccan/tcon
to always be typesafe.  It handles both integer and pointer types.

No real change for users.

Previously, it was always "", since we left the nul terminator at the
start.

This happens in SAMBA with the TDB_VERSION1, presumably due to a
read-only traverse nested inside a normal traverse (since it doesn't
occur without TDB_VERSION1).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

This clarifies the code a little, but also provides a more explicit
mechanism which can be used to debug error handling (by introducing
tdb_err_t and making it a pointer type).

Measuring ccanlint -d ccan/tdb2 on my dual core hyperthread laptop gives:
Before: 5:30
After: 3:31

Lazy cut & paste of tdb names causes failure when we run in parallel.

Measuring ccanlint -d ccan/tdb2 on my dual core hyperthread laptop gives:
Before: 5:59
After: 5:30

Measuring ccanlint -d ccan/tdb2 on my dual core hyperthread laptop gives:
Before: 6:47
After: 5:59

We use the lbalance module to figure out how many to run in parallel.

Reallocing smaller can move the pointer; certainly valgrind detects
it.  Found while chasing intermittant errors on "make fastcheck".

Meets all of the requirements of ccanlint.
Code coverage of the tests covers everything except for a malloc() failure.
Added some xml files for the tests to work on.

Removed the last references of the old buffering method. Should be
stable now. Time to write some proper testing.

tdb_repack() returns an enum TDB_ERROR, whereas
tdb1_transaction_commit is expected to return 0 or -1.

A left-over -1 return; should be returning ecode (probably TDB_ERR_IO).

Since enums and ints are compatible in C, the compiler didn't warn
that our prototypes for these functions disagreed with the
definitions.