tests/test-serve.t

statfs: change Linux feature detection

Previously we check three things: "statfs" function, "linux/magic.h" and
"sys/vfs.h" headers. But we didn't check "struct statfs" or the "f_type"
field. That means if a system has "statfs" but "struct statfs" is not
defined in the two header files we check, or defined without the "f_type"
field, the compilation will fail.

This patch combines the checks (2 headers + 1 function + 1 field) together
and sets "HAVE_LINUX_STATFS". It makes setup.py faster (less checks), and
more reliable (immutable to the issue above).

#require serve

  $ hgserve()
  > {
  >    hg serve -a localhost -d --pid-file=hg.pid -E errors.log -v $@ \
  >        | sed -e "s/:$HGPORT1\\([^0-9]\\)/:HGPORT1\1/g" \
  >              -e "s/:$HGPORT2\\([^0-9]\\)/:HGPORT2\1/g" \
  >              -e 's/http:\/\/[^/]*\//http:\/\/localhost\//'
  >    cat hg.pid >> "$DAEMON_PIDS"
  >    echo % errors
  >    cat errors.log
  >    killdaemons.py hg.pid
  > }

  $ hg init test
  $ cd test
  $ echo '[web]' > .hg/hgrc
  $ echo 'accesslog = access.log' >> .hg/hgrc
  $ echo "port = $HGPORT1" >> .hg/hgrc

Without -v

  $ hg serve -a localhost -p $HGPORT -d --pid-file=hg.pid -E errors.log
  $ cat hg.pid >> "$DAEMON_PIDS"
  $ if [ -f access.log ]; then
  >     echo 'access log created - .hg/hgrc respected'
  > fi
  access log created - .hg/hgrc respected

errors

  $ cat errors.log

With -v

  $ hgserve
  listening at http://localhost/ (bound to *$LOCALIP*:HGPORT1) (glob)
  % errors

With -v and -p HGPORT2

  $ hgserve -p "$HGPORT2"
  listening at http://localhost/ (bound to *$LOCALIP*:HGPORT2) (glob)
  % errors

With -v and -p daytime (should fail because low port)

#if no-root
  $ KILLQUIETLY=Y
  $ hgserve -p daytime
  abort: cannot start server at 'localhost:13': Permission denied
  abort: child process failed to start
  % errors
  $ KILLQUIETLY=N
#endif

With --prefix foo

  $ hgserve --prefix foo
  listening at http://localhost/foo/ (bound to *$LOCALIP*:HGPORT1) (glob)
  % errors

With --prefix /foo

  $ hgserve --prefix /foo
  listening at http://localhost/foo/ (bound to *$LOCALIP*:HGPORT1) (glob)
  % errors

With --prefix foo/

  $ hgserve --prefix foo/
  listening at http://localhost/foo/ (bound to *$LOCALIP*:HGPORT1) (glob)
  % errors

With --prefix /foo/

  $ hgserve --prefix /foo/
  listening at http://localhost/foo/ (bound to *$LOCALIP*:HGPORT1) (glob)
  % errors

  $ cd ..