[sanitizer_common] Define internal_usleep on Solaris

[ro]

Summary

The Solaris/amd64 buildbot has recently been broken several times, at least one of those
remains unfixed:

[63/446] Generating Sanitizer-x86_64-Test
[...]
Undefined			first referenced
 symbol  			    in file
_ZN11__sanitizer15internal_usleepEy /opt/llvm-buildbot/home/solaris11-amd64/clang-solaris11-amd64/stage1/projects/compiler-rt/lib/sanitizer_common/tests/libRTSanitizerCommon.test.x86_64.a(sanitizer_common.cpp.o)
ld: fatal: symbol referencing errors

Thist patch fixes it by defining the missing internal_usleep.

Tested on amd64-pc-solaris2.11.

[dvyukov]

Thanks for fixing this rather than reverting my commit :)

You can do:
nanosleep(&ts, nullptr);
Passing in the second pointer is something I forgot to cleanup in my change.
But otherwise looks good to me.

[ro]

Ignore remaining time from nanosleep.

[ro]

In D105878#2873340, @dvyukov wrote:

Thanks for fixing this rather than reverting my commit :)

Sure: I prefer that if it's easy as in this case.

You can do:
nanosleep(&ts, nullptr);
Passing in the second pointer is something I forgot to cleanup in my change.

Makes sense and passed a quick retest as expected.

But otherwise looks good to me.

Thanks.

compiler-rt/lib/sanitizer_common/sanitizer_solaris.cpp

DECLARE__REAL_AND_INTERNAL(uptr, rename, const char *oldpath,
                            const char *newpath) {
   return _REAL(rename)(oldpath, newpath);
 }
 
 DECLARE__REAL_AND_INTERNAL(uptr, sched_yield, void) {
   return sched_yield();
 }
 
+DECLARE__REAL_AND_INTERNAL(void, usleep, u64 useconds) {
+  struct timespec ts;
+  ts.tv_sec = useconds / 1000000;
+  ts.tv_nsec = (useconds % 1000000) * 1000;
+  nanosleep(&ts, nullptr);
+}
+
 DECLARE__REAL_AND_INTERNAL(uptr, execve, const char *filename,
                            char *const argv[], char *const envp[]) {
   return _REAL(execve)(filename, argv, envp);
 }
 
 DECLARE__REAL_AND_INTERNAL(uptr, waitpid, int pid, int *status, int options) {
   return _REAL(waitpid)(pid, status, options);
 }