Many headers are expected to expose a subset of the type definitions
in time.h. time.h has a whole bunch of messy logic for conditionally
defining some its types and structs, but, as best I can tell, this
has never worked 100%. In particular, __need_timespec is ineffective
if _TIME_H has already been defined, which means that if you compile
#include <time.h>
#include <sched.h>
with e.g. -fsyntax-only -std=c89 -Wall -Wsystem-headers, you will get
In file included from test.c:2:0:
/usr/include/sched.h:74:57: warning: "struct timespec" declared inside
parameter list will not be visible outside of this definition or declaration
extern int sched_rr_get_interval (__pid_t __pid, struct timespec *__t) __THROW;
^~~~~~~~
And if you want to _use_ sched_rr_get_interval in a TU compiled that
way, you're hosed.
This patch replaces all of that with small bits/types/TYPE.h headers
as introduced earlier. time.h and bits/time.h are now *much* simpler,
and a lot of other headers are slightly simpler.
* time/time.h, bits/time.h, sysdeps/unix/sysv/linux/bits/time.h:
Remove all logic conditional on __need macros. Move all the
conditionally defined types to their own headers...
* time/bits/types/clock_t.h: Define clock_t here.
* time/bits/types/clockid_t.h: Define clockid_t here.
* time/bits/types/struct_itimerspec.h: Define struct itimerspec here.
* time/bits/types/struct_timespec.h: Define struct timespec here.
* time/bits/types/struct_timeval.h: Define struct timeval here.
* time/bits/types/struct_tm.h: Define struct tm here.
* time/bits/types/time_t.h: Define time_t here.
* time/bits/types/timer_t.h: Define timer_t here.
* time/Makefile: Install the new headers.
* bits/resource.h, io/fcntl.h, io/sys/poll.h, io/sys/stat.h
* io/utime.h, misc/sys/select.h, posix/sched.h, posix/sys/times.h
* posix/sys/types.h, resolv/netdb.h, rt/aio.h, rt/mqueue.h
* signal/signal.h, pthread/semaphore.h, sysdeps/nptl/pthread.h
* sysdeps/unix/sysv/linux/alpha/bits/resource.h
* sysdeps/unix/sysv/linux/alpha/sys/acct.h
* sysdeps/unix/sysv/linux/bits/resource.h
* sysdeps/unix/sysv/linux/bits/timex.h
* sysdeps/unix/sysv/linux/mips/bits/resource.h
* sysdeps/unix/sysv/linux/net/ppp_defs.h
* sysdeps/unix/sysv/linux/sparc/bits/resource.h
* sysdeps/unix/sysv/linux/sys/acct.h
* sysdeps/unix/sysv/linux/sys/timerfd.h
* sysvipc/sys/msg.h, sysvipc/sys/sem.h, sysvipc/sys/shm.h
* time/sys/time.h, time/sys/timeb.h
Use the new bits/types headers.
* include/time.h: Remove __need logic.
* include/bits/time.h
* include/bits/types/clock_t.h, include/bits/types/clockid_t.h
* include/bits/types/time_t.h, include/bits/types/timer_t.h
* include/bits/types/struct_itimerspec.h
* include/bits/types/struct_timespec.h
* include/bits/types/struct_timeval.h
* include/bits/types/struct_tm.h:
New wrapper headers.
Some headers did not include all of their prerequisite headers.
* rpcsvc/nislib.h: Include rpcsvc/nis.h.
* sysdeps/unix/sysv/linux/netrose/rose.h:
Include sys/socket.h and netax25/ax25.h.
<endian.h> only defines BYTE_ORDER, BIG_ENDIAN, LITTLE_ENDIAN,
etc. under __USE_MISC; glibc's headers should use __BYTE_ORDER,
__BIG_ENDIAN, __LITTLE_ENDIAN, etc. instead.
* inet/netinet/icmp6.h, inet/netinet/ip6.h
* resolv/arpa/nameser_compat.h:
Use __BYTE_ORDER etc. instead of BYTE_ORDER etc.
sys/types.h only conditionally defines caddr_t and clockid_t.
* sysdeps/unix/sysv/linux/sys/quota.h:
Use __caddr_t instead of caddr_t.
* sysdeps/unix/sysv/linux/sys/timerfd.h:
Use __clockid_t instead of clockid_t.
Remove a #warning that was the sole actual problem with using sys/ipc.h
without _GNU_SOURCE/_XOPEN_SOURCE.
* sysvipc/sys/ipc.h: Remove unnecessary #warning.
_LIBC, __USE_XOPEN2K8, and __STDC_VERSION__ are not always defined.
It seems to me that _LIBC should not appear in installed headers, but
avoiding that for argp specifically would require more surgery than
feels appropriate for this patch set. It's possible that
"#ifdef _LIBC" would be sufficient, but I wanted to be conservative.
All three versions of bits/socket.h want to know whether __flexarr
will produce a real flexible array member -- specifically, one that
doesn't alter sizeof(the structure containing it). They were testing
for this with a complicated #if condition that did not agree with
sys/cdefs.h and that tripped -Wundef warnings under -std=c90.
I added a new macro to sys/cdefs.h, __glibc_c99_flexarr_available,
which reveals exactly what these headers want to know. I also took
the opportunity to flatten the rather messy conditional nest defining
__flexarr.
* argp/argp.h: Check whether _LIBC is defined before expanding it.
* posix/glob.h: Check whether __USE_XOPEN2K8 is defined instead
of expanding it.
* misc/sys/cdefs.h: Tidy up conditional nest defining __flexarr.
Define __glibc_c99_flexarr_available to 1 when the compiler
supports C99-compatible flexible array members, 0 otherwise.
* sysdeps/unix/sysv/linux/bits/socket.h
* sysdeps/mach/hurd/bits/socket.h
* bits/socket.h: Use __glibc_c99_flexarr_available in
definitions of struct cmsghdr and CMSG_DATA.