This code uses QueryPerformanceCounter() [**] on Windows,
mach_absolute_time() on OSX, clock_gettime() where available, and
gettimeofday() [*] elsewhere.
Timer types are stored in an opaque OS-specific format; the only
supported operation is to compute the difference between two timers.
[*] As you know, gettimeofday() isn't monotonic, so we include
a simple ratchet function to ensure that it only moves forward.
[**] As you may not know, QueryPerformanceCounter() isn't actually
always as monotonic as you might like it to be, so we ratchet that
one too.
We also include a "coarse monotonic timer" for cases where we don't
actually need high-resolution time. This is GetTickCount{,64}() on
Windows, clock_gettime(CLOCK_MONOTONIC_COARSE) on Linux, and falls
back to regular monotonic time elsewhere.
I grepped and hand-inspected the "it's" instances, to see if any
were supposed to be possessive. While doing that, I found a
"the the", so I grepped to see if there were any more.
Only some very ancient distributions don't ship with Libevent 2 anymore,
even the oldest supported Ubuntu LTS version has it. This allows us to
get rid of a lot of compat code.
Validate that tv_usec inputs to tv_udiff and tv_mdiff are in range.
Do internal calculations in tv_udiff and tv_mdiff in 64-bit,
which makes the function less prone to integer overflow,
particularly on platforms where long and time_t are 32-bit,
but tv_sec is 64-bit, like some BSD configurations.
Check every addition and subtraction that could overflow.
Make sure to memset(0) the destination buffer so we don't leave any
uninitialized data.
Fixes#19462
Signed-off-by: David Goulet <dgoulet@torproject.org>
base16_decodes() now returns the number of decoded bytes. It's interface
changes from returning a "int" to a "ssize_t". Every callsite now checks the
returned value.
Fixes#14013
Signed-off-by: David Goulet <dgoulet@torproject.org>
realloc()ing a thing in order to try to save memory on it just
doesn't make sense with today's allocators. Instead, let's use the
fact that whenever we decompress something, either it isn't too big,
or we chop it up, or we reallocate it.
zlib 1.2 came out in 2003; earlier versions should be dead by now.
Our workaround code was only preventing us from using the gzip
encoding (if we decide to do so), and having some dead code linger
around in torgzip.c
The Autoconf macro AC_USE_SYSTEM_EXTENSIONS defines preprocessor macros
which turn on extensions to C and POSIX. The macro also makes it easier
for developers to use the extensions without needing (or forgetting) to
define them manually.
The macro can be safely used because it was introduced in Autoconf 2.60
and Tor requires Autoconf 2.63 and above.
