#!/usr/bin/env python
from waflib import Logs, Options, Errors

import os, sys

if Options.options.disable_fault_handling:
    conf.DEFINE('HAVE_DISABLE_FAULT_HANDLING',1)

# backtrace could be in libexecinfo or in libc.
# This is our preferred backtrace handler (more useful output than libunwind as at Ubuntu 20.04 x86_64)
conf.CHECK_FUNCS_IN('backtrace backtrace_symbols', 'execinfo', checklibc=True, headers='execinfo.h')
conf.CHECK_HEADERS('execinfo.h')

conf.SET_TARGET_TYPE('LIBUNWIND', 'EMPTY')
if Options.options.with_libunwind:
    if conf.check_cfg(package='libunwind-generic',
                      args='--cflags --libs',
                      msg='Checking for libunwind',
                      uselib_store='LIBUNWIND',
                      mandatory=False):
        if conf.CHECK_HEADERS('libunwind.h'):
            conf.SET_TARGET_TYPE('LIBUNWIND', 'SYSLIB')
    else:
        raise Errors.WafError('--with-libunwind specified but libunwind not found')
elif Options.options.with_libunwind == None:
    if not conf.CONFIG_SET('HAVE_BACKTRACE_SYMBOLS') \
       and not Options.options.disable_fault_handling:
        raise Errors.WafError(
'''backtrace_symbols() not found but
--with-libunwind not specified.
Use --without-libunwind to build without internal backtrace support or
--disable-fault-handling to totally defer fault handling to the OS.''')

conf.CHECK_STRUCTURE_MEMBER('struct statvfs', 'f_frsize', define='HAVE_FRSIZE', headers='sys/statvfs.h')

# all the different ways of doing statfs
statfs_types = [
    ( 'STAT_STATVFS',
      'statvfs (SVR4)',
      'struct statvfs fsd; exit(statvfs(0, &fsd))',
      'sys/statvfs.h' ),

    ( 'STAT_STATFS3_OSF1',
      '3-argument statfs function (DEC OSF/1)',
      'struct statfs fsd; fsd.f_fsize = 0; exit(statfs(".", &fsd, sizeof(struct statfs)))',
      'sys/param.h sys/mount.h' ),

    ( 'STAT_STATFS2_BSIZE',
      'two-argument statfs with statfs.bsize',
      'struct statfs fsd; fsd.f_bsize = 0; exit(statfs(".", &fsd))',
      'sys/param.h sys/mount.h  sys/vfs.h' ),

    ( 'STAT_STATFS4',
      'four-argument statfs  (AIX-3.2.5, SVR3)',
      'struct statfs fsd; exit(statfs(".", &fsd, sizeof fsd, 0))',
      'sys/statfs.h' ),

    ( 'STAT_STATFS2_FSIZE',
      'two-argument statfs with statfs.fsize',
      'struct statfs fsd; fsd.f_fsize = 0; exit(statfs(".", &fsd))',
      'sys/param.h sys/mount.h' ),

    ( 'STAT_STATFS2_FS_DATA',
      'two-argument statfs with struct fs_data (Ultrix)',
      'struct fs_data fsd; exit(statfs(".", &fsd) != 1)',
      'sys/param.h sys/mount.h sys/fs_types.h' )
]

found_statfs=False
for (define, msg, code, headers) in statfs_types:
    if conf.CHECK_CODE(code,
                       define=define,
                       headers=headers,
                       msg='Checking for %s' % msg,
                       local_include=False):
        found_statfs=True
        break

if not found_statfs:
    print("FATAL: Failed to find a statfs method")
    raise

conf.CHECK_CODE("""struct statfs fsd;
		fsd.f_bsize = 0;
		fsd.f_iosize = 0;
		return (statfs (".", &fsd));
		""",
                headers='sys/param.h sys/mount.h sys/vfs.h',
                define='BSD_STYLE_STATVFS',
                msg='Checking for *bsd style statfs with statfs.f_iosize',
                execute=True,
                local_include=False)

conf.CHECK_CODE('struct statvfs buf; buf.f_fsid = 0',
                define='HAVE_FSID_INT',
                msg='Checking if f_fsid is an integer',
                execute=False,
                local_include=False,
                headers='sys/statvfs.h')

# fsusage.c assumes that statvfs has an f_frsize entry. Some weird
# systems use f_bsize.
conf.CHECK_CODE('struct statvfs buf; buf.f_frsize = 0',
                define='HAVE_FRSIZE',
                msg='Checking that statvfs.f_frsize works',
                headers='sys/statvfs.h',
                execute=False,
                local_include=False)

# Some systems use f_flag in struct statvfs while others use f_flags
conf.CHECK_CODE('struct statvfs buf; buf.f_flag = 0',
                define='HAVE_STATVFS_F_FLAG',
                msg='Checking whether statvfs.f_flag exists',
                headers='sys/statvfs.h',
                local_include=False,
                execute=False)

conf.CHECK_CODE('struct statvfs buf; buf.f_flags = 0',
                define='HAVE_STATVFS_F_FLAGS',
                msg='Checking whether statvfs.f_flags exists',
                headers='sys/statvfs.h',
                local_include=False,
                execute=False)

# Check for mallinfo2() first and fallback to mallinfo() if not found
body = '''mi.arena + mi.ordblks + mi.smblks + mi.hblks + mi.hblkhd +
    mi.usmblks + mi.fsmblks +  mi.uordblks + mi.fordblks + mi.keepcost'''
if not conf.CHECK_CODE('''struct mallinfo2 mi = mallinfo2(); return %s;'''
                       % body, 'HAVE_MALLINFO2',
                       msg="Checking for mallinfo2()",
                       headers='malloc.h'):
    conf.CHECK_CODE('''struct mallinfo mi = mallinfo(); return %s;'''
                    % body, 'HAVE_MALLINFO',
                    msg="Checking for mallinfo()",
                    headers='malloc.h')

#
# systemd removed the libsystemd-daemon and libsystemd-journal libraries. In newer
# versions it is only libsystemd. As waf pkg-config handling does not provide
# targets which could be used as a dependency based on the package name we need
# to look for them on our own. This enabled one of the library targets based on
# which version we detect.
#
conf.SET_TARGET_TYPE('systemd-daemon', 'EMPTY')
conf.SET_TARGET_TYPE('systemd-journal', 'EMPTY')
conf.SET_TARGET_TYPE('systemd', 'EMPTY')

if Options.options.enable_systemd != False:
    r_daemon = conf.CHECK_CFG(package='libsystemd-daemon', args='--cflags --libs',
                   msg='Checking for libsystemd-daemon')
    r_journal = conf.CHECK_CFG(package='libsystemd-journal', args='--cflags --libs',
                   msg='Checking for libsystemd-journal')
    if r_daemon is None and r_journal is None:
        conf.CHECK_CFG(package='libsystemd', args='--cflags --libs',
                   msg='Checking for libsystemd')
        conf.CHECK_LIB('systemd', shlib=True)
    else:
        conf.CHECK_LIB('systemd-daemon', shlib=True)
        conf.CHECK_LIB('systemd-journal', shlib=True)

conf.SET_TARGET_TYPE('lttng-ust', 'EMPTY')

if Options.options.enable_lttng != False:
    conf.CHECK_CFG(package='lttng-ust', args='--cflags --libs',
                   msg='Checking for lttng-ust', uselib_store="LTTNG-UST")
    conf.CHECK_HEADERS('lttng/tracef.h', lib='lttng-st')
    conf.CHECK_LIB('lttng-ust', shlib=True)

if (conf.CONFIG_SET('HAVE_LTTNG_TRACEF_H') and
    conf.CONFIG_SET('HAVE_LTTNG_UST')):
    conf.DEFINE('HAVE_LTTNG_TRACEF', '1')
    conf.env['HAVE_LTTNG_TRACEF'] = True

if Options.options.gpfs_headers_dir:
    conf.env['CPPPATH_GPFS'] = Options.options.gpfs_headers_dir
    if conf.CHECK_HEADERS('gpfs.h', False, False, "gpfs"):
        Logs.info('Using gpfs.h from %s' % Options.options.gpfs_headers_dir)
        conf.DEFINE('HAVE_GPFS', '1')
else:
    conf.env['CPPPATH_GPFS'] = "/usr/lpp/mmfs/include/"
    if conf.CHECK_HEADERS('gpfs.h', False, False, "gpfs"):
        Logs.info('Using gpfs.h from installed gpfs package.')
        conf.DEFINE('HAVE_GPFS', '1')
    else:
        if sys.platform.startswith('linux'):
            conf.env['CPPPATH_GPFS'] = os.path.abspath("third_party/gpfs")
            if conf.CHECK_HEADERS('gpfs.h', False, False, "gpfs"):
                Logs.info('Using gpfs.h from third_party directory.')
                conf.DEFINE('HAVE_GPFS', '1')
