Build ForkWithFlags and part of NamespaceSandbox under nonsfi newlib.

sandbox/linux/system_headers/linux_signal.h

Index: sandbox/linux/system_headers/linux_signal.h
diff --git a/sandbox/linux/system_headers/linux_signal.h b/sandbox/linux/system_headers/linux_signal.h
index 5db7fc5ea1dba01b659232c92c03b21a42380d6e..87b3a9a1bd2a2b512e7e2173a605d7376eaf304c 100644
--- a/sandbox/linux/system_headers/linux_signal.h
+++ b/sandbox/linux/system_headers/linux_signal.h
@@ -16,8 +16,17 @@
 
 #include <signal.h>
 
+
+#define LINUX_SIGHUP 1    // 1 in PNaCl toolchain. Defined for consistency.

[rickyz (no longer on Chrome), 2015/06/16 20:57:07]

I got these from
native_client/toolchain/linux_x86/pnacl_newlib/le32-nacl/include/sys/signal.h -
is that correct?

+#define LINUX_SIGINT 2    // 2 in PNaCl toolchain. Defined for consistency.
+#define LINUX_SIGQUIT 3   // 3 in PNaCl toolchain. Defined for consistency.
+#define LINUX_SIGABRT 6   // 6 in PNaCl toolchain. Defined for consistency.
 #define LINUX_SIGBUS 7    // 10 in PNaCl toolchain.
+#define LINUX_SIGUSR1 10  // 30 in PNaCl toolchain.
 #define LINUX_SIGSEGV 11  // 11 in PNaCl toolchain. Defined for consistency.
+#define LINUX_SIGUSR2 12  // 31 in PNaCl toolchain.
+#define LINUX_SIGPIPE 13  // 13 in PNaCl toolchain. Defined for consistency.
+#define LINUX_SIGTERM 15  // 15 in PNaCl toolchain. Defined for consistency.
 #define LINUX_SIGCHLD 17  // 20 in PNaCl toolchain.
 #define LINUX_SIGSYS 31   // 12 in PNaCl toolchain.
 
@@ -47,8 +56,16 @@ struct LinuxSigInfo {
 // Just alias the toolchain's value.
 #include <signal.h>
 
+#define LINUX_SIGHUP SIGHUP

[jln (very slow on Chromium), 2015/06/18 18:23:20]

Wouldn't it be better to:

1. Always use the #define above for LINUX_* always
2. Add a COMPILE_ASSERT for each to check that they match when we do have the
system headers

[rickyz (no longer on Chrome), 2015/06/18 22:50:57]

Done.

+#define LINUX_SIGINT SIGINT
+#define LINUX_SIGQUIT SIGQUIT
+#define LINUX_SIGABRT SIGABRT
 #define LINUX_SIGBUS SIGBUS
+#define LINUX_SIGUSR1 SIGUSR1
 #define LINUX_SIGSEGV SIGSEGV
+#define LINUX_SIGUSR2 SIGUSR2
+#define LINUX_SIGPIPE SIGPIPE
+#define LINUX_SIGTERM SIGTERM
 #define LINUX_SIGCHLD SIGCHLD
 #define LINUX_SIGSYS SIGSYS