procd: improve early console handling

The malta target is broken since procd is used
as init. The initramfs image boots fine, however
the console is not working.

Improve the early console handling to fix the
problem.

Signed-off-by: Gabor Juhos <[email protected]>

SVN-Revision: 37451

package/system/procd/Makefile

@@ -2,7 +2,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=procd
 PKG_VERSION:=2013-07-14
-PKG_RELEASE=$(PKG_SOURCE_VERSION)
+PKG_RELEASE=$(PKG_SOURCE_VERSION)-1
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL:=git://nbd.name/luci2/procd.git

package/system/procd/patches/0001-early-keep-stdio-files-open.patch

@@ -0,0 +1,49 @@
+From 13ebb50d2789de7bd47cebe57e3f6eba58fdcc7e Mon Sep 17 00:00:00 2001
+From: Gabor Juhos <[email protected]>
+Date: Fri, 19 Jul 2013 08:43:35 +0200
+Subject: [PATCH 1/2] early: keep stdio files open
+
+At the end of the 'early_console' function, the
+file descriptor is closed unconditionally. This
+'close' call closes the stdio files if the fd
+returned by the 'open(dev/console)' call equals
+with any of the STD{IN,OUT,ERR}_FILENO values.
+When this happens, all subsequent accesses to
+the stdio files will fail and early console
+access won't work.
+
+To avoid this, don't close the file descriptor if
+that equals with any of the STD*_FILENO values.
+
+Signed-off-by: Gabor Juhos <[email protected]>
+---
+Note:
+
+The issue happens if Linux is unable to open the
+initial console before calling init. In this case,
+the 'open(dev/console)' call in the 'early_console'
+function returns with zero.
+---
+ early.c |    6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+diff --git a/early.c b/early.c
+index 27d0929..204623b 100644
+--- a/early.c
++++ b/early.c
+@@ -65,7 +65,11 @@ static void early_console(const char *dev)
+ 	dup2(dd, STDIN_FILENO);
+ 	dup2(dd, STDOUT_FILENO);
+ 	dup2(dd, STDERR_FILENO);
+-	close(dd);
++
++	if (dd != STDIN_FILENO &&
++	    dd != STDOUT_FILENO &&
++	    dd != STDERR_FILENO)
++		close(dd);
+ }
+ 
+ static void early_env(void)
+-- 
+1.7.10
+

package/system/procd/patches/0002-early-remove-superfluous-close-of-stdio-file-descrip.patch

@@ -0,0 +1,40 @@
+From 1edd25cfa0a26dac1ca5d49bce479ebdea336437 Mon Sep 17 00:00:00 2001
+From: Gabor Juhos <[email protected]>
+Date: Fri, 19 Jul 2013 08:21:17 +0200
+Subject: [PATCH 2/2] early: remove superfluous close of stdio file
+ descriptors
+
+'man dup2' says:
+
+  dup2() makes newfd be the copy of oldfd, closing newfd first if
+  necessary, but note the following:
+
+  *  If oldfd is not a valid file descriptor, then the call fails,
+     and newfd is not closed.
+
+  *  If oldfd is a valid file descriptor, and newfd has the same
+     value as oldfd, then dup2() does nothing, and returns newfd.
+
+Signed-off-by: Gabor Juhos <[email protected]>
+---
+ early.c |    4 ----
+ 1 file changed, 4 deletions(-)
+
+diff --git a/early.c b/early.c
+index 204623b..f9e3277 100644
+--- a/early.c
++++ b/early.c
+@@ -53,10 +53,6 @@ static void early_console(const char *dev)
+ 		mkdev("*console", 0600);
+ 
+ 	dd = open(dev, O_RDWR);
+-	close(STDIN_FILENO);
+-	close(STDOUT_FILENO);
+-	close(STDERR_FILENO);
+-
+ 	if (dd < 0) {
+ 		ERROR("Failed to open %s\n", dev);
+ 		return;
+-- 
+1.7.10
+