From bf8e5ecab729e89332e4e0d062f2f226dcac15e7 Mon Sep 17 00:00:00 2001
From: Ingo Weinhold <ingo_weinhold@gmx.de>
Date: Sun, 15 Jul 2007 00:45:10 +0000
Subject: [PATCH] * Reduced the region allocated for the uncompressed data to
 16 MB. With   32 MB the kernel's VM initialization code would run into
 trouble.   Accessing freshly mapped memory in the generic page mapper would  
 result in a page fault. To be investigated. * Apparently in the boot loader
 the file systems are responsible for   resolving symbolic links (instead of
 the VFS). We do that now.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@21608 a95241bf-73f2-0310-859d-f6bbb57e9c96
---
 .../boot/loader/file_systems/tarfs/tarfs.cpp  | 47 ++++++++++---------
 1 file changed, 24 insertions(+), 23 deletions(-)

diff --git a/src/system/boot/loader/file_systems/tarfs/tarfs.cpp b/src/system/boot/loader/file_systems/tarfs/tarfs.cpp
index 4b41c0be4f..84a3b88858 100644
--- a/src/system/boot/loader/file_systems/tarfs/tarfs.cpp
+++ b/src/system/boot/loader/file_systems/tarfs/tarfs.cpp
@@ -34,7 +34,7 @@
 
 
 static const uint32 kFloppyArchiveOffset = 192 * 1024;	// at 192 kB
-static const size_t kTarRegionSize = 32 * 1024 * 1024;		// 32 MB
+static const size_t kTarRegionSize = 16 * 1024 * 1024;	// 16 MB
 
 namespace TarFS {
 
@@ -143,6 +143,8 @@ class Symlink : public ::Node, public Entry {
 		virtual off_t Size() const;
 		virtual ino_t Inode() const;
 
+		const char* LinkPath() const	{ return fHeader->linkname; }
+
 		virtual ::Node *ToNode() { return this; }
 
 	private:
@@ -367,15 +369,29 @@ TarFS::Directory::LookupEntry(const char *name)
 
 
 ::Node *
-TarFS::Directory::Lookup(const char *name, bool /*traverseLinks*/)
+TarFS::Directory::Lookup(const char *name, bool traverseLinks)
 {
-	if (TarFS::Entry *entry = LookupEntry(name)) {
-		entry->ToNode()->Acquire();
-			// our entries are not supposed to be deleted after use
-		return entry->ToNode();
+	TarFS::Entry *entry = LookupEntry(name);
+	if (!entry)
+		return NULL;
+
+	Node* node = entry->ToNode();
+
+	if (traverseLinks) {
+		if (S_ISLNK(node->Type())) {
+			Symlink* symlink = static_cast<Symlink*>(node);
+			int fd = open_from(this, symlink->LinkPath(), O_RDONLY);
+			if (fd >= 0) {
+				node = get_node_from(fd);
+				close(fd);
+			}
+		}
 	}
 
-	return NULL;
+	if (node)
+		node->Acquire();
+
+	return node;
 }
 
 
@@ -536,22 +552,7 @@ TarFS::Symlink::~Symlink()
 ssize_t
 TarFS::Symlink::ReadAt(void *cookie, off_t pos, void *buffer, size_t bufferSize)
 {
-	TRACE(("tarfs: symlink read at %Ld, %lu bytes, fSize = %Ld\n", pos,
-		bufferSize, fSize));
-
-	if (pos < 0 || !buffer)
-		return B_BAD_VALUE;
-
-	if (pos >= fSize || bufferSize == 0)
-		return 0;
-
-	size_t toRead = fSize - pos;
-	if (toRead > bufferSize)
-		toRead = bufferSize;
-
-	memcpy(buffer, fHeader->linkname + pos, toRead);
-
-	return toRead;
+	return B_NOT_ALLOWED;
 }