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-rw-r--r--src/thread/__rsyscall.c114
1 files changed, 0 insertions, 114 deletions
diff --git a/src/thread/__rsyscall.c b/src/thread/__rsyscall.c
deleted file mode 100644
index e885d9e7..00000000
--- a/src/thread/__rsyscall.c
+++ /dev/null
@@ -1,114 +0,0 @@
-#include "pthread_impl.h"
-
-/* "rsyscall" is a mechanism by which a thread can synchronously force all
- * other threads to perform an arbitrary syscall. It is necessary to work
- * around the non-conformant implementation of setuid() et al on Linux,
- * which affect only the calling thread and not the whole process. This
- * implementation performs some tricks with signal delivery to work around
- * the fact that it does not keep any list of threads in userspace. */
-
-static struct {
- volatile int lock, hold, blocks, cnt;
- unsigned long arg[6];
- int nr;
- int err;
- int init;
-} rs;
-
-static void rsyscall_handler(int sig, siginfo_t *si, void *ctx)
-{
- struct pthread *self = __pthread_self();
- long r;
-
- if (!rs.hold || rs.cnt == libc.threads_minus_1) return;
-
- /* Threads which have already decremented themselves from the
- * thread count must not increment rs.cnt or otherwise act. */
- if (self->dead) {
- sigfillset(&((ucontext_t *)ctx)->uc_sigmask);
- return;
- }
-
- r = __syscall(rs.nr, rs.arg[0], rs.arg[1],
- rs.arg[2], rs.arg[3], rs.arg[4], rs.arg[5]);
- if (r < 0) rs.err=-r;
-
- a_inc(&rs.cnt);
- __wake(&rs.cnt, 1, 1);
- while(rs.hold)
- __wait(&rs.hold, 0, 1, 1);
- a_dec(&rs.cnt);
- if (!rs.cnt) __wake(&rs.cnt, 1, 1);
-}
-
-int __rsyscall(int nr, long a, long b, long c, long d, long e, long f)
-{
- int i, ret;
- sigset_t set = { 0 };
- struct pthread *self;
-
- if (!libc.threads_minus_1)
- return syscall(nr, a, b, c, d, e, f);
-
- self = __pthread_self();
-
- LOCK(&rs.lock);
- while ((i=rs.blocks))
- __wait(&rs.blocks, 0, i, 1);
-
- __syscall(SYS_rt_sigprocmask, SIG_BLOCK, (uint64_t[]){-1}, &set, 8);
-
- if (!rs.init) {
- struct sigaction sa = {
- .sa_flags = SA_SIGINFO | SA_RESTART,
- .sa_sigaction = rsyscall_handler,
- .sa_mask = set
- };
- sigfillset(&sa.sa_mask);
- sa.sa_sigaction = rsyscall_handler;
- __libc_sigaction(SIGSYSCALL, &sa, 0);
- rs.init = 1;
- }
-
- rs.nr = nr;
- rs.arg[0] = a; rs.arg[1] = b;
- rs.arg[2] = c; rs.arg[3] = d;
- rs.arg[4] = d; rs.arg[5] = f;
- rs.err = 0;
- rs.cnt = 0;
- rs.hold = 1;
-
- /* Dispatch signals until all threads respond */
- for (i=libc.threads_minus_1; i; i--)
- sigqueue(self->pid, SIGSYSCALL, (union sigval){0});
- while ((i=rs.cnt) < libc.threads_minus_1) {
- sigqueue(self->pid, SIGSYSCALL, (union sigval){0});
- __wait(&rs.cnt, 0, i, 1);
- }
-
- /* Handle any lingering signals with no-op */
- __syscall(SYS_rt_sigprocmask, SIG_SETMASK, &set, &set, 8);
-
- /* Resume other threads' signal handlers and wait for them */
- rs.hold = 0;
- __wake(&rs.hold, -1, 0);
- while((i=rs.cnt)) __wait(&rs.cnt, 0, i, 1);
-
- if (rs.err) errno = rs.err, ret = -1;
- else ret = syscall(nr, a, b, c, d, e, f);
-
- UNLOCK(&rs.lock);
- return ret;
-}
-
-void __rsyscall_lock()
-{
- a_inc(&rs.blocks);
- while (rs.lock) __wait(&rs.lock, 0, 1, 1);
-}
-
-void __rsyscall_unlock()
-{
- a_dec(&rs.blocks);
- if (rs.lock) __wake(&rs.blocks, 1, 1);
-}