add sysv ipc message queues (completely untested)

src/ipc/msgctl.c

@@ -0,0 +1,12 @@
+#include <sys/msg.h>
+#include "syscall.h"
+#include "ipc.h"
+
+int msgctl(int q, int cmd, struct msqid_ds *buf)
+{
+#ifdef __NR_msgctl
+	return syscall(SYS_msgctl, q, cmd, buf);
+#else
+	return syscall(SYS_ipc, IPCOP_msgctl, q, cmd, buf);
+#endif
+}

src/ipc/msgget.c

@@ -0,0 +1,12 @@
+#include <sys/msg.h>
+#include "syscall.h"
+#include "ipc.h"
+
+int msgget(key_t k, int flag)
+{
+#ifdef __NR_msgget
+	return syscall(SYS_msgget, k, flag);
+#else
+	return syscall(SYS_ipc, IPCOP_msgget, k, flag);
+#endif
+}

src/ipc/msgrcv.c

@@ -0,0 +1,17 @@
+#include <sys/msg.h>
+#include "syscall.h"
+#include "ipc.h"
+#include "libc.h"
+
+ssize_t msgrcv(int q, void *m, size_t len, long type, int flag)
+{
+	ssize_t r;
+	CANCELPT_BEGIN;
+#ifdef __NR_msgrcv
+	r = syscall(SYS_msgrcv, q, m, len, type, flag);
+#else
+	r = syscall(SYS_ipc, IPCOP_msgrcv, q, len, flag, ((long[]){ (long)m, type }));
+#endif
+	CANCELPT_END;
+	return r;
+}

src/ipc/msgsnd.c

@@ -0,0 +1,17 @@
+#include <sys/msg.h>
+#include "syscall.h"
+#include "ipc.h"
+#include "libc.h"
+
+ssize_t msgsnd(int q, const void *m, size_t len, int flag)
+{
+	ssize_t r;
+	CANCELPT_BEGIN;
+#ifdef __NR_msgsnd
+	r = syscall(SYS_msgsnd, q, m, len, flag);
+#else
+	r = syscall(SYS_ipc, IPCOP_msgsnd, q, len, flag, m);
+#endif
+	CANCELPT_END;
+	return r;
+}