From b9b697f2cb9d0e6c9af177a0b55b23e5b636b008 Mon Sep 17 00:00:00 2001
From: Jonas 'Sortie' Termansen <sortie@maxsi.org>
Date: Sun, 9 Sep 2012 12:21:39 +0200
Subject: [PATCH] Implement proper W* error codes in sys/wait.h and kernel.

Note that signals can't really kill a process at this time.
---
 sortix/include/sortix/wait.h | 12 ++++++++++++
 sortix/process.cpp           |  4 ++--
 utils/chvideomode.cpp        |  3 +--
 utils/init.cpp               |  2 +-
 utils/mxsh.cpp               | 15 ++++++++++-----
 5 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/sortix/include/sortix/wait.h b/sortix/include/sortix/wait.h
index ca0dd3c3..00711aff 100644
--- a/sortix/include/sortix/wait.h
+++ b/sortix/include/sortix/wait.h
@@ -31,6 +31,18 @@ __BEGIN_DECLS
 
 #define WNOHANG (1<<0)
 
+#define WEXITSTATUS(status) ((status >> 8) & 0xFF)
+#define WTERMSIG(status) ((status >> 0) & 0x7F)
+#define WSTOPSIG(status) WTERMSIG(status)
+#define WIFEXITED(status) (WTERMSIG(status) == 0)
+#define WIFSIGNALED(status) (WTERMSIG(status) != 0)
+/*#define WIFCONTINUED(status) (WTERMSIG(status) == TODO)*/
+/*#define WIFSTOPPED(status) (WTERMSIG(status) == TODO)*/
+/*#define WIFCONTINUED(status) (WTERMSIG(status) == TODO)*/
+
+#define W_EXITCODE(ret, sig) ((ret) << 8 | (sig))
+#define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
+
 __END_DECLS
 
 #endif
diff --git a/sortix/process.cpp b/sortix/process.cpp
index 6c8f68a4..6593096b 100644
--- a/sortix/process.cpp
+++ b/sortix/process.cpp
@@ -374,7 +374,7 @@ namespace Sortix
 
 		int exitstatus = zombie->exitstatus;
 		if ( exitstatus < 0 )
-			exitstatus = 0;
+			exitstatus = W_EXITCODE(128 + SIGKILL, SIGKILL);
 
 		// TODO: Validate that status is a valid user-space int!
 		if ( status )
@@ -396,7 +396,7 @@ namespace Sortix
 		ScopedLock lock(&threadlock);
 		// Status codes can only contain 8 bits according to ISO C and POSIX.
 		if ( exitstatus == -1 )
-			exitstatus = status % 256;
+			exitstatus = W_EXITCODE(status & 0xFF, 0);
 
 		// Broadcast SIGKILL to all our threads which will begin our long path
 		// of process termination. We simply can't stop the threads as they may
diff --git a/utils/chvideomode.cpp b/utils/chvideomode.cpp
index c1aa0cd9..dfb20e68 100644
--- a/utils/chvideomode.cpp
+++ b/utils/chvideomode.cpp
@@ -365,14 +365,13 @@ Try make sure the desired driver is loaded and is configured correctly.\n");
 		if ( childpid < 0 ) { perror("fork"); exit(1); }
 		if ( childpid )
 		{
-			// TODO: Use the right WEXITSTATUS-ish macros here!
 			int status;
 			waitpid(childpid, &status, 0);
 			if ( !SetCurrentMode(prevmode) )
 			{
 				error(1, errno, "Unable to restore video mode: %s", prevmode);
 			}
-			exit(status);
+			exit(WEXITSTATUS(status));
 		}
 		execvp(argv[1], argv + 1);
 		perror(argv[1]);
diff --git a/utils/init.cpp b/utils/init.cpp
index 77fed09b..0a199790 100644
--- a/utils/init.cpp
+++ b/utils/init.cpp
@@ -50,7 +50,7 @@ int runsystem()
 		int status;
 		waitpid(childpid, &status, 0);
 		// TODO: Use the proper macro!
-		if ( 128 <= status )
+		if ( 128 <= WEXITSTATUS(status) || WIFSIGNALED(status) )
 		{
 			printf("Looks like the system crashed, trying to bring it back up.\n");
 			return runsystem();
diff --git a/utils/mxsh.cpp b/utils/mxsh.cpp
index 4648cd21..0be0d9f6 100644
--- a/utils/mxsh.cpp
+++ b/utils/mxsh.cpp
@@ -173,21 +173,26 @@ readcmd:
 		}
 
 		status = internalresult;
-		if ( !internal && waitpid(childpid, &status, 0) < 0 )
+		int exitstatus;
+		if ( !internal && waitpid(childpid, &exitstatus, 0) < 0 )
 		{
 			perror("waitpid");
 			return 127;
 		}
 
+		// TODO: HACK: Most signals can't kill processes yet.
+		if ( WEXITSTATUS(exitstatus) == 128 + SIGINT )
+			printf("^C\n");
+		if ( WTERMSIG(status) == SIGKILL )
+			printf("Killed\n");
+
+		status = WEXITSTATUS(exitstatus);
+
 		if ( strcmp(execmode, ";") == 0 && tokens[cmdnext] && !lastcmd )
 		{
 			goto readcmd;
 		}
 
-		// TODO: Hack, use the right macros!
-		if ( status == 128 + SIGINT )
-			printf("^C\n");
-
 		result = status;
 		goto out;
 	}