clang warns that the generator assignment is conditional which could
lead to passing an undefined variable to printf.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

TCON suggests placing _tcon members last in structs. Placing variable
sized structs anywhere but last is apparently a gcc extension that
gives warnings under clang.

This applies to tlists because they use TCON internally. Update the
docs and examples to place tlists last and so compile without clang
warnings.

There are other places where this occurs; they will be dealt with
separately.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Running 'tools/ccan_depends --compile ccan/crypto' without this
patch will demonstrate the crash.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Closes: 47

Closes: 46

Closes: 45

The header macro RIPEMD160_INIT is intended to be used instead I believe.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

The resulting code is just as clear to read, so lets not require
a C99 compiler to compile this.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

The documentation for hex_encode indicates that it returns simply true or
false. The old implementation was returning the written length on success,
cast to boolean. This will elicit a warning under MSVC.

On further examination, there is no need to check/modify the length inside
the loop, since we can check it once before starting. As a result the code
can be simplified a bit.

A side affect of this change is that nothing will be written at all if the
length is incorrect, vs the previous code writing characters until the length
available is exhausted. I prefer the new semantics but YMMV.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Show the derivation of the constants to match the comment above them.
The compiler doesn't care, but it helps the code read better.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

The code already assigns to/from bytes as a size_t, so make it
official (and better on platforms with a 32 bit size_t).

Moving bytes makes it act as a canary in the event that there is a rogue
write/off by one somewhere - since it ends up in the hash we are
more likely to detect this should we corrupt it. This also makes the
working buffer better aligned which can't hurt.

Also, initialise the buffer to zero while we are changing the initialisation
macro anyway. It costs little compared to the hashing overhead, should be
optimised away if redundant in most cases, and it removes a warning from both
gcc and clang about unititialised struct members.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

This reads better. Also remove duplicated comments for the members.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

These are just aliases to a buffer: its customary for these to
have the same size, and makes sizeof() consistent in case anyone
decides to use the members instead of the containing union.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Prevents warnings from gcc at higher warning levels.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Prevents warnings from gcc at higher warning levels.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Prevents warnings from gcc at higher warning levels.
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

altstack/test/run.c uses some hairy macros to intercept the standard
library functions that altstack uses.  This has two purposes: 1) to
conditionally cause those functions to fail, and thereby test altstack's
error paths, and 2) log which of the library functions was called in each
testcase.

The second function isn't actually useful - for the purposes of testing the
module, we want to check the actual behaviour, not what calls it made in
what order to accomplish it.  Explicitly checking the calls makes it much
harder to change altstack's implementation without breaking the tests.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

In a number of places the altstack module uses a literal '0' for pointer
values.  That's correct C, but doesn't make it obvious on a quick read
whether values are integers or pointers.  This patch changes those cases
to use the NULL define instead.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Functions invoked with altstack take a void * parameter.  However, the
test program wants to pass an integer, and so uses the trick of casting
the integer values to (void *) and back again.

The ptrint() module handles exactly this case in a more portable and
(somewhat) typesafe way, so use that instead.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

altstack relies on catching a SIGSEGV caused when overrunning the stack.
This means that the SEGV handler itself can't use the already overflowed
stack, and so we use sigaltstack() to assign the signal handler a different
stack.  On completion, altstack() clears the alternate signal stack.

However, it's possible that the calling program could be using
sigaltstack() for its own reasons, so it's more correct to restore the
sigaltstack() state to that from the beginning of the altstack() call.
This patch implements this behaviour.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

altstack uses a number of __thread variables to track internal state.  This
allows altstack to be thread-safe, although it's still not re-entrant.
This patch gathers all these variables into a single per-thread state
structure.  This makes it easy to see at a glance what the whole of the
required state is, and thereby easier to reason about correctness of
changes to the implementation.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Common case is mapping ints to structures.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Useful for unwinding actions taken while iterating over a htable.
Signed-off-by: Cody P Schafer <dev@codyps.com>

An odd omission from the tlist module is basic tlist_next() and
tlist_prev() macros matching list_next() and list_prev() in the basic
list module.  This adds them.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Sometimes it's not convenient to initialize an agar graph at runtime with
agar_init_graph().  This adds an AGAR_INIT_GRAPH() macro to do the same
thing as a static initializer.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

These were left over from a previous approach which didn't pan out.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Signed-off-by: Cody P Schafer <dev@codyps.com>

I did not see any failures of other modules with this change, but I'm
not completely certain there are no cases that it breaks.
Signed-off-by: Cody P Schafer <dev@codyps.com>

When other macros are emitting LIST_INIT expansions, `name` can get a
bit complicated.
Signed-off-by: Cody P Schafer <dev@codyps.com>

Without this, one had to either use a function or a macro with casts to
get the expected behavior.
Signed-off-by: Cody P Schafer <dev@codyps.com>

Signed-off-by: Cody P Schafer <dev@codyps.com>