[PATCH v3 30/40] bsd-user/signal.c: sigset manipulation routines.

[Warner Losh <imp@bsdimp.com>]

target_sigemptyset: resets a set to having no bits set
target_sigaddset:   adds a signal to a set
target_sigismember: returns true when signal is a member
host_to_target_sigset_internal: convert host sigset to target
host_to_target_sigset: convert host sigset to target
target_to_host_sigset_internal: convert target sigset to host
target_to_host_sigset: convert target sigset to host

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Kyle Evans <kevans@freebsd.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 bsd-user/signal-common.h |  2 ++
 bsd-user/signal.c        | 74 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 76 insertions(+)

diff --git a/bsd-user/signal-common.h b/bsd-user/signal-common.h
index 80e9503238a..ee819266f54 100644
--- a/bsd-user/signal-common.h
+++ b/bsd-user/signal-common.h
@@ -14,11 +14,13 @@ abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
 long do_sigreturn(CPUArchState *env);
 void force_sig_fault(int sig, int code, abi_ulong addr);
 int host_to_target_signal(int sig);
+void host_to_target_sigset(target_sigset_t *d, const sigset_t *s);
 void process_pending_signals(CPUArchState *env);
 void queue_signal(CPUArchState *env, int sig, int si_type,
                   target_siginfo_t *info);
 void signal_init(void);
 int target_to_host_signal(int sig);
+void target_to_host_sigset(sigset_t *d, const target_sigset_t *s);
 
 /*
  * Within QEMU the top 8 bits of si_code indicate which of the parts of the
diff --git a/bsd-user/signal.c b/bsd-user/signal.c
index 34663f7a28a..84dafa4e9fe 100644
--- a/bsd-user/signal.c
+++ b/bsd-user/signal.c
@@ -32,6 +32,9 @@
 
 static struct target_sigaction sigact_table[TARGET_NSIG];
 static void host_signal_handler(int host_sig, siginfo_t *info, void *puc);
+static void target_to_host_sigset_internal(sigset_t *d,
+        const target_sigset_t *s);
+
 
 /*
  * The BSD ABIs use the same singal numbers across all the CPU architectures, so
@@ -48,6 +51,25 @@ int target_to_host_signal(int sig)
     return sig;
 }
 
+static inline void target_sigemptyset(target_sigset_t *set)
+{
+    memset(set, 0, sizeof(*set));
+}
+
+static inline void target_sigaddset(target_sigset_t *set, int signum)
+{
+    signum--;
+    uint32_t mask = (uint32_t)1 << (signum % TARGET_NSIG_BPW);
+    set->__bits[signum / TARGET_NSIG_BPW] |= mask;
+}
+
+static inline int target_sigismember(const target_sigset_t *set, int signum)
+{
+    signum--;
+    abi_ulong mask = (abi_ulong)1 << (signum % TARGET_NSIG_BPW);
+    return (set->__bits[signum / TARGET_NSIG_BPW] & mask) != 0;
+}
+
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
@@ -60,6 +82,58 @@ static inline void rewind_if_in_safe_syscall(void *puc)
     }
 }
 
+/*
+ * Note: The following take advantage of the BSD signal property that all
+ * signals are available on all architectures.
+ */
+static void host_to_target_sigset_internal(target_sigset_t *d,
+        const sigset_t *s)
+{
+    int i;
+
+    target_sigemptyset(d);
+    for (i = 1; i <= NSIG; i++) {
+        if (sigismember(s, i)) {
+            target_sigaddset(d, host_to_target_signal(i));
+        }
+    }
+}
+
+void host_to_target_sigset(target_sigset_t *d, const sigset_t *s)
+{
+    target_sigset_t d1;
+    int i;
+
+    host_to_target_sigset_internal(&d1, s);
+    for (i = 0; i < _SIG_WORDS; i++) {
+        d->__bits[i] = tswap32(d1.__bits[i]);
+    }
+}
+
+static void target_to_host_sigset_internal(sigset_t *d,
+        const target_sigset_t *s)
+{
+    int i;
+
+    sigemptyset(d);
+    for (i = 1; i <= TARGET_NSIG; i++) {
+        if (target_sigismember(s, i)) {
+            sigaddset(d, target_to_host_signal(i));
+        }
+    }
+}
+
+void target_to_host_sigset(sigset_t *d, const target_sigset_t *s)
+{
+    target_sigset_t s1;
+    int i;
+
+    for (i = 0; i < TARGET_NSIG_WORDS; i++) {
+        s1.__bits[i] = tswap32(s->__bits[i]);
+    }
+    target_to_host_sigset_internal(d, &s1);
+}
+
 static bool has_trapno(int tsig)
 {
     return tsig == TARGET_SIGILL ||
-- 
2.33.1