bsd-user: Add do_bsd_semop implementation

Add implementation of semop(2) syscall to perform System V semaphore
operations. Converts target sembuf array to host format and executes
operations.

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>

diff --git a/bsd-user/bsd-misc.h b/bsd-user/bsd-misc.h
index 3dffb977a5440aeb91774c8ca037eaf0d4c4d314..e1e552b58f5a70ed9823bf77eb786ede994f7dc0 100644 (file)
--- a/bsd-user/bsd-misc.h
+++ b/bsd-user/bsd-misc.h
@@ -77,6 +77,28 @@ static inline abi_long do_bsd_semget(abi_long key, int nsems,
                 target_to_host_bitmask(target_flags, ipc_flags_tbl)));
 }
 
+/* semop(2) */
+static inline abi_long do_bsd_semop(int semid, abi_long ptr, unsigned nsops)
+{
+    g_autofree struct sembuf *sops = g_malloc(nsops * sizeof(struct sembuf));
+    struct target_sembuf *target_sembuf;
+    int i;
+
+    target_sembuf = lock_user(VERIFY_READ, ptr,
+            nsops * sizeof(struct target_sembuf), 1);
+    if (target_sembuf == NULL) {
+        return -TARGET_EFAULT;
+    }
+    for (i = 0; i < nsops; i++) {
+        __get_user(sops[i].sem_num, &target_sembuf[i].sem_num);
+        __get_user(sops[i].sem_op, &target_sembuf[i].sem_op);
+        __get_user(sops[i].sem_flg, &target_sembuf[i].sem_flg);
+    }
+    unlock_user(target_sembuf, ptr, 0);
+
+    return semop(semid, sops, nsops);
+}
+
 /* getdtablesize(2) */
 static inline abi_long do_bsd_getdtablesize(void)
 {