header inclusion cleanup

make comment more precise

all reads from stdin and writes to stdout will be retried until the
whole operation completes or an unrecoverable condition is detected

refactor some code out to write_pidfile() in util.c

Revert sockfilt.c back to revision 1.42

Changes introduced in revision 1.43 were useless

Avoid timeout restart when signal caught while awaiting socket and stdin events

juggle() actually returns bool.

Remove redundant and unreachable log message.

Reduce to 20 seconds the time allowed to set SO_REUSEADDR option on sockfilt listener socket.

Log some more error descriptions.

sockfilt will quit when orphaned

Use a long int data type to handle getpid() result

logmsg already appends '\n'

Enabled a few more gcc warnings with --enable-debug. Renamed a few
variables to avoid shadowing global declarations.

Make the ftp server connect to the address given by curl in the PORT/EPRT
instead of hard-coding it to 127.0.0.1

Fixed a few compiler warnings. Try to do a slightly better job of
cleaning up after an OOM condition in curl_multi_add_handle

added a size > buffer size check to make it easier to track this in the
future

Upped the buffer size to 17000+ bytes to prepare for the upcoming test 1003
that verfies ridiculously long server response lines. Also changed sprintf
to snprintf in a few places.

start the retry delay at 10 ms, double it for every failed attempt which makes
it 10 seconds delay after 11 attempts

the timeout was probably too short with max = 1 sec, so lets test with 5 sec.

added time loop to sockfilt.c in order to wait for SO_REUSEADDR;
added go_sleep() to util.c.

add debug messages for initialization failures

use macros ERRNO, SET_ERRNO(), SOCKERRNO and SET_SOCKERRNO() for errno handling

use macros ERRNO, SET_ERRNO(), SOCKERRNO and SET_SOCKERRNO() for errno handling

Update copyright year, since the file has been modified

Replace is*() macros with our own IS*() ones.

Check for USE_WINSOCK instead of WIN32 where the check was done
to verify winsock API availability.