Hide __signalfd4, used to implement signalfd(3).

Bug: 11156955
Change-Id: I50842279cb5b32ec8bd45193435574e415cd806e
diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index 83feb65..4a21582 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -228,7 +228,7 @@
 int     __rt_sigprocmask:rt_sigprocmask(int, const sigset_t*, sigset_t*, size_t)  all
 int     __rt_sigsuspend:rt_sigsuspend(const sigset_t*, size_t)  all
 int     __rt_sigtimedwait:rt_sigtimedwait(const sigset_t*, struct siginfo_t*, struct timespec_t*, size_t)  all
-int     signalfd4(int, const sigset_t*, size_t, int)  all
+int     __signalfd4:signalfd4(int, const sigset_t*, size_t, int)  all
 
 # sockets
 int           socket(int, int, int)              arm,arm64,mips,mips64,x86_64
diff --git a/libc/arch-arm/syscalls/signalfd4.S b/libc/arch-arm/syscalls/__signalfd4.S
similarity index 87%
rename from libc/arch-arm/syscalls/signalfd4.S
rename to libc/arch-arm/syscalls/__signalfd4.S
index f8d8a28..712f975 100644
--- a/libc/arch-arm/syscalls/signalfd4.S
+++ b/libc/arch-arm/syscalls/__signalfd4.S
@@ -2,7 +2,7 @@
 
 #include <private/bionic_asm.h>
 
-ENTRY(signalfd4)
+ENTRY(__signalfd4)
     mov     ip, r7
     ldr     r7, =__NR_signalfd4
     swi     #0
@@ -11,4 +11,4 @@
     bxls    lr
     neg     r0, r0
     b       __set_errno
-END(signalfd4)
+END(__signalfd4)
diff --git a/libc/arch-arm64/syscalls/signalfd4.S b/libc/arch-arm64/syscalls/__signalfd4.S
similarity index 86%
rename from libc/arch-arm64/syscalls/signalfd4.S
rename to libc/arch-arm64/syscalls/__signalfd4.S
index 7a8f7f7..91510f6 100644
--- a/libc/arch-arm64/syscalls/signalfd4.S
+++ b/libc/arch-arm64/syscalls/__signalfd4.S
@@ -2,7 +2,7 @@
 
 #include <private/bionic_asm.h>
 
-ENTRY(signalfd4)
+ENTRY(__signalfd4)
     stp     x29, x30, [sp, #-16]!
     mov     x29,  sp
     str     x8,       [sp, #-16]!
@@ -18,4 +18,5 @@
     b.hi    __set_errno
 
     ret
-END(signalfd4)
+END(__signalfd4)
+.hidden __signalfd4
diff --git a/libc/arch-mips/syscalls/signalfd4.S b/libc/arch-mips/syscalls/__signalfd4.S
similarity index 87%
rename from libc/arch-mips/syscalls/signalfd4.S
rename to libc/arch-mips/syscalls/__signalfd4.S
index e2c2a30..cc9b212 100644
--- a/libc/arch-mips/syscalls/signalfd4.S
+++ b/libc/arch-mips/syscalls/__signalfd4.S
@@ -2,7 +2,7 @@
 
 #include <private/bionic_asm.h>
 
-ENTRY(signalfd4)
+ENTRY(__signalfd4)
     .set noreorder
     .cpload t9
     li v0, __NR_signalfd4
@@ -16,4 +16,4 @@
     j t9
     nop
     .set reorder
-END(signalfd4)
+END(__signalfd4)
diff --git a/libc/arch-mips64/syscalls/signalfd4.S b/libc/arch-mips64/syscalls/__signalfd4.S
similarity index 86%
rename from libc/arch-mips64/syscalls/signalfd4.S
rename to libc/arch-mips64/syscalls/__signalfd4.S
index 594c73d..c4fe77b 100644
--- a/libc/arch-mips64/syscalls/signalfd4.S
+++ b/libc/arch-mips64/syscalls/__signalfd4.S
@@ -2,7 +2,7 @@
 
 #include <private/bionic_asm.h>
 
-ENTRY(signalfd4)
+ENTRY(__signalfd4)
     .set push
     .set noreorder
     li v0, __NR_signalfd4
@@ -22,4 +22,5 @@
     j t9
     move ra, t0
     .set pop
-END(signalfd4)
+END(__signalfd4)
+.hidden __signalfd4
diff --git a/libc/arch-x86/syscalls/signalfd4.S b/libc/arch-x86/syscalls/__signalfd4.S
similarity index 94%
rename from libc/arch-x86/syscalls/signalfd4.S
rename to libc/arch-x86/syscalls/__signalfd4.S
index 1fe6c68..7cbe474 100644
--- a/libc/arch-x86/syscalls/signalfd4.S
+++ b/libc/arch-x86/syscalls/__signalfd4.S
@@ -2,7 +2,7 @@
 
 #include <private/bionic_asm.h>
 
-ENTRY(signalfd4)
+ENTRY(__signalfd4)
     pushl   %ebx
     pushl   %ecx
     pushl   %edx
@@ -31,4 +31,4 @@
     popl    %ecx
     popl    %ebx
     ret
-END(signalfd4)
+END(__signalfd4)
diff --git a/libc/arch-x86_64/syscalls/signalfd4.S b/libc/arch-x86_64/syscalls/__signalfd4.S
similarity index 84%
rename from libc/arch-x86_64/syscalls/signalfd4.S
rename to libc/arch-x86_64/syscalls/__signalfd4.S
index 4d8a1b6..fafe371 100644
--- a/libc/arch-x86_64/syscalls/signalfd4.S
+++ b/libc/arch-x86_64/syscalls/__signalfd4.S
@@ -2,7 +2,7 @@
 
 #include <private/bionic_asm.h>
 
-ENTRY(signalfd4)
+ENTRY(__signalfd4)
     movq    %rcx, %r10
     movl    $__NR_signalfd4, %eax
     syscall
@@ -14,4 +14,5 @@
     orq     $-1, %rax
 1:
     ret
-END(signalfd4)
+END(__signalfd4)
+.hidden __signalfd4
diff --git a/libc/bionic/signalfd.cpp b/libc/bionic/signalfd.cpp
index 36ef81d..63e1db4 100644
--- a/libc/bionic/signalfd.cpp
+++ b/libc/bionic/signalfd.cpp
@@ -30,9 +30,9 @@
 
 #include "private/kernel_sigset_t.h"
 
-extern "C" int signalfd4(int fd, kernel_sigset_t* mask, size_t sizemask, int flags);
+extern "C" int __signalfd4(int fd, kernel_sigset_t* mask, size_t sizemask, int flags);
 
 int signalfd(int fd, const sigset_t* mask, int flags) {
   kernel_sigset_t in_set(mask);
-  return signalfd4(fd, &in_set, sizeof(in_set), flags);
+  return __signalfd4(fd, &in_set, sizeof(in_set), flags);
 }