From 8e329d12c791862ad3cd395b481831be3d62320d Mon Sep 17 00:00:00 2001
From: Joshua Peraza <jperaza@chromium.org>
Date: Fri, 19 Oct 2018 13:14:36 -0700
Subject: [PATCH] linux: Use capget syscall instead of its libc wrapper

The sys/capability.h header is only present if libcap is installed. We
were only using it for its declaration of a capget() wrapper. Using the
system call directly allows compiling without installing libcap.

Change-Id: I83dfc5c8d56bb3cdd4efb62e0c568d8a221334cd
Reviewed-on: https://chromium-review.googlesource.com/c/1292231
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
---
 handler/linux/exception_handler_server.cc | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/handler/linux/exception_handler_server.cc b/handler/linux/exception_handler_server.cc
index 71a5dc74..12e73635 100644
--- a/handler/linux/exception_handler_server.cc
+++ b/handler/linux/exception_handler_server.cc
@@ -15,10 +15,11 @@
 #include "handler/linux/exception_handler_server.h"
 
 #include <errno.h>
-#include <sys/capability.h>
+#include <linux/capability.h>
 #include <sys/epoll.h>
 #include <sys/eventfd.h>
 #include <sys/socket.h>
+#include <sys/syscall.h>
 #include <sys/types.h>
 #include <unistd.h>
 
@@ -95,7 +96,7 @@ bool HaveCapSysPtrace() {
 
   cap_header.pid = getpid();
 
-  if (capget(&cap_header, &cap_data) != 0) {
+  if (syscall(SYS_capget, &cap_header, &cap_data) != 0) {
     PLOG(ERROR) << "capget";
     return false;
   }