Rewrite all BPF policies to use DSL API

content/common/sandbox_linux/sandbox_seccomp_bpf_linux.cc

Index: content/common/sandbox_linux/sandbox_seccomp_bpf_linux.cc
diff --git a/content/common/sandbox_linux/sandbox_seccomp_bpf_linux.cc b/content/common/sandbox_linux/sandbox_seccomp_bpf_linux.cc
index 8a6fa7204f7c599a3b8e880af1b6e8a2db9b0bf9..fe3ee3ce14562deece0314ade921fa7bee613063 100644
--- a/content/common/sandbox_linux/sandbox_seccomp_bpf_linux.cc
+++ b/content/common/sandbox_linux/sandbox_seccomp_bpf_linux.cc
@@ -35,6 +35,7 @@
 #include "sandbox/linux/seccomp-bpf/sandbox_bpf.h"
 #include "sandbox/linux/services/linux_syscalls.h"
 
+using namespace sandbox::bpf_dsl;
 using sandbox::BaselinePolicy;
 using sandbox::SyscallSets;
 
@@ -76,23 +77,17 @@ class BlacklistDebugAndNumaPolicy : public SandboxBPFBasePolicy {
   BlacklistDebugAndNumaPolicy() {}
   virtual ~BlacklistDebugAndNumaPolicy() {}
 
-  virtual ErrorCode EvaluateSyscall(SandboxBPF* sandbox_compiler,
-                                    int system_call_number) const OVERRIDE;
+  virtual ResultExpr EvaluateSyscall(int system_call_number) const OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BlacklistDebugAndNumaPolicy);
 };
 
-ErrorCode BlacklistDebugAndNumaPolicy::EvaluateSyscall(SandboxBPF* sandbox,
-                                                       int sysno) const {
-  if (!SandboxBPF::IsValidSyscallNumber(sysno)) {
-    // TODO(jln) we should not have to do that in a trivial policy.
-    return ErrorCode(ENOSYS);
-  }
+ResultExpr BlacklistDebugAndNumaPolicy::EvaluateSyscall(int sysno) const {
   if (SyscallSets::IsDebug(sysno) || SyscallSets::IsNuma(sysno))
-    return sandbox->Trap(sandbox::CrashSIGSYS_Handler, NULL);
+    return Trap(sandbox::CrashSIGSYS_Handler, NULL);
 
-  return ErrorCode(ErrorCode::ERR_ALLOWED);
+  return Allow();
 }
 
 class AllowAllPolicy : public SandboxBPFBasePolicy {
@@ -100,8 +95,7 @@ class AllowAllPolicy : public SandboxBPFBasePolicy {
   AllowAllPolicy() {}
   virtual ~AllowAllPolicy() {}
 
-  virtual ErrorCode EvaluateSyscall(SandboxBPF* sandbox_compiler,
-                                    int system_call_number) const OVERRIDE;
+  virtual ResultExpr EvaluateSyscall(int system_call_number) const OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AllowAllPolicy);
@@ -110,13 +104,8 @@ class AllowAllPolicy : public SandboxBPFBasePolicy {
 // Allow all syscalls.
 // This will still deny x32 or IA32 calls in 64 bits mode or
 // 64 bits system calls in compatibility mode.
-ErrorCode AllowAllPolicy::EvaluateSyscall(SandboxBPF*, int sysno) const {
-  if (!SandboxBPF::IsValidSyscallNumber(sysno)) {
-    // TODO(jln) we should not have to do that in a trivial policy.
-    return ErrorCode(ENOSYS);
-  } else {
-    return ErrorCode(ErrorCode::ERR_ALLOWED);
-  }
+ResultExpr AllowAllPolicy::EvaluateSyscall(int sysno) const {
+  return Allow();
 }
 
 // If a BPF policy is engaged for |process_type|, run a few sanity checks.