[RFC][PATCH 1/9] initramfs: separate reading cpio method from header

Mimi Zohar
2015-01-07T20:52:52Z

In preparation for adding xattr support, read the CPIO method separately
from the rest of the header.

Signed-off-by: Mimi Zohar <zohar-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
---
init/initramfs.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/init/initramfs.c b/init/initramfs.c
index bece48c..527703e 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -187,6 +187,7 @@ static void __init parse_header(char *s)

static __initdata enum state {
Start,
+ GotFormat,
Collect,
GotHeader,
SkipIt,
@@ -230,7 +231,7 @@ static __initdata char *header_buf, *symlink_buf, *name_buf;

static int __init do_start(void)
{
- read_into(header_buf, 110, GotHeader);
+ read_into(header_buf, 6, GotFormat);
return 0;
}

@@ -248,7 +249,7 @@ static int __init do_collect(void)
return 0;
}

-static int __init do_header(void)
+static int __init do_format(void)
{
if (memcmp(collected, "070707", 6)==0) {
error("incorrect cpio method used: use -H newc option");
@@ -258,6 +259,12 @@ static int __init do_header(void)
error("no cpio magic");
return 1;
}
+ read_into(header_buf, 104, GotHeader);
+ return 0;
+}
+
+static int __init do_header(void)
+{
parse_header(collected);
next_header = this_header + N_ALIGN(name_len) + body_len;
next_header = (next_header + 3) & ~3;
@@ -400,6 +407,7 @@ static int __init do_symlink(void)

static __initdata int (*actions[])(void) = {
[Start] = do_start,
+ [GotFormat] = do_format,
[Collect] = do_collect,
[GotHeader] = do_header,
[SkipIt] = do_skip,
--
1.8.1.4