adapter/syscall: fix ioctl conflicting types compile error on older glibc

adapter/syscall/ff_declare_syscalls.h

@@ -22,7 +22,6 @@ FF_SYSCALL_DECL(ssize_t, recvfrom, (int, void *, size_t, int,
 FF_SYSCALL_DECL(ssize_t, sendmsg, (int, const struct msghdr *, int flags));
 FF_SYSCALL_DECL(ssize_t, recvmsg, (int, struct msghdr *, int flags));
 FF_SYSCALL_DECL(int, close, (int));
-FF_SYSCALL_DECL(int, ioctl, (int, unsigned long, unsigned long));
 FF_SYSCALL_DECL(int, fcntl, (int, int, unsigned long));
 FF_SYSCALL_DECL(int, epoll_create, (int));
 FF_SYSCALL_DECL(int, epoll_ctl, (int, int, int, struct epoll_event *));

adapter/syscall/ff_hook_syscall.c

@@ -1,6 +1,7 @@
 #include <assert.h>
 #include <dlfcn.h>
 #include <unistd.h>
+#include <stdarg.h>
 #include <sys/epoll.h>
 #include <sys/resource.h>
 #include <errno.h>
@@ -1882,6 +1883,25 @@ ff_hook_ioctl(int fd, unsigned long req, unsigned long data)
     RETURN_NOFREE();
 }
 
+/*
+ * Public ioctl() entry point with variadic signature matching glibc's
+ * declaration: int ioctl(int fd, unsigned long request, ...)
+ * This avoids the 'conflicting types' compile error when strong_alias is
+ * used against the fixed-arg ff_hook_ioctl prototype (issue #942).
+ */
+int
+ioctl(int fd, unsigned long req, ...)
+{
+    va_list ap;
+    unsigned long data;
+
+    va_start(ap, req);
+    data = va_arg(ap, unsigned long);
+    va_end(ap);
+
+    return ff_hook_ioctl(fd, req, data);
+}
+
 int
 ff_hook_fcntl(int fd, int cmd, unsigned long data)
 {

adapter/syscall/ff_linux_syscall.c

@@ -22,6 +22,8 @@
 struct ff_linux_syscall {
     #define FF_SYSCALL_DECL(ret, fn, args)  ret (*pf_##fn) args;
     #include "ff_declare_syscalls.h"
+    /* ioctl removed from ff_declare_syscalls.h (issue #942 fix), add manually */
+    int (*pf_ioctl)(int, unsigned long, unsigned long);
 };
 
 static int linux_syscall_inited;
@@ -44,6 +46,8 @@ linux_syscall_load_symbol()
     #define FF_SYSCALL_DECL(ret, fn, args)  \
     syscalls.pf_##fn = (typeof(syscalls.pf_##fn))dlsym(linux_lib_handle, #fn);
     #include <ff_declare_syscalls.h>
+    /* ioctl removed from ff_declare_syscalls.h (issue #942 fix), load manually */
+    syscalls.pf_ioctl = (typeof(syscalls.pf_ioctl))dlsym(linux_lib_handle, "ioctl");
 
     return 0;
 }

adapter/syscall/ff_linux_syscall.h

@@ -10,4 +10,8 @@
 #define FF_SYSCALL_DECL(ret, fn, args) ret ff_linux_##fn args
 #include "ff_declare_syscalls.h"
 
+/* ioctl is removed from ff_declare_syscalls.h (variadic conflict fix, issue #942),
+ * declare ff_linux_ioctl explicitly here. */
+int ff_linux_ioctl(int fd, unsigned long req, unsigned long data);
+
 #endif