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: 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>

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

All modules have a _info file (a C file, despite the lack of extension)
giving metadata for the module.  The Makefiles have a rule to build these..
but it's broken (missing an include directive).

This patch fixes the rule, and builds the info binaries for all modules by
default.  This is a useful check and also useful for manually inspecting
a module's metadata.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Currently, build of ccan is controlled by two Make variables: MODS_WITH_SRC
and MODS_NO_SRC which list modules containing .c files, and modules with
only .h files respectively.

When adding new modules this is fiddly to get right, and there are a number
of modules already listed in the wrong variable.  There's also some
redundant logic in the DIRS variable to again filter out modules without
source.

This simplifies things by having a single manually updated MODS variable
listing every module, and determining MODS_WITH_SOURCE programmatically.
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>

We used to crash, as reported by Stephen M. Cameron

Closes: #39
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

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

Signed-off-by: Stephen M. Cameron <stephenmcameron@gmail.com>

Currently we pull auto-generated dependencies into the Makefile with
include ccan/*/*.d.  That will omit any .d files from nested modules,
meaning things might not be correctly rebuilt there.

Correct this by using the list of modules instead of a 1-level wildcard.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

We currently generated .d dependency files with the -MD option to cc.  That
includes system header files in the dependencies, which isn't often useful
and makes the .d more complicated than necessary.

This changes to -MMD which excludes system headers.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Most of the ccan Makefiles use $(RM) to remove files.  However, 'rm' is
traditionally considered one of the few shell tools which can be used in
Makefiles without indirecting via a variable.

rm is also typically invoked with -f in Makefiles, so that it doesn't cause
errors if the files don't exist (because they haven't been built).  A
number of instances in ccan were missing this.

This corrects these warts.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

At present, "make clean" will not remove the module-Makefile files for
non-top-level modules.  It also won't remove the generated config.h.
Correct those errors.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Seems to want more stack.
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>

Turns out that patterns with / cause % to match /.  OK...
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>