Mailing List Archive

Move the crc and its state into struct gunzip_state. In the process, expand the
only use of CRC_VALUE as it is hides what is being compared.

Signed-off-by: Daniel P. Smith <dpsmith@apertussolutions.com>
---
xen/common/gzip/gunzip.c | 11 +++++++----
xen/common/gzip/inflate.c | 14 +++++---------
2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/xen/common/gzip/gunzip.c b/xen/common/gzip/gunzip.c
index 0043ff8ac886..26d2a4aa9d36 100644
--- a/xen/common/gzip/gunzip.c
+++ b/xen/common/gzip/gunzip.c
@@ -20,6 +20,9 @@ struct gunzip_state {

unsigned long bb; /* bit buffer */
unsigned int bk; /* bits in bit buffer */
+
+ uint32_t crc_32_tab[256];
+ uint32_t crc;
};

#define malloc(a) xmalloc_bytes(a)
@@ -72,7 +75,7 @@ static __init void flush_window(struct gunzip_state *s)
* The window is equal to the output buffer therefore only need to
* compute the crc.
*/
- unsigned long c = crc;
+ unsigned int c = s->crc;
unsigned int n;
unsigned char *in, ch;

@@ -80,9 +83,9 @@ static __init void flush_window(struct gunzip_state *s)
for ( n = 0; n < s->wp; n++ )
{
ch = *in++;
- c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
+ c = s->crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
}
- crc = c;
+ s->crc = c;

s->bytes_out += (unsigned long)s->wp;
s->wp = 0;
@@ -119,7 +122,7 @@ __init int perform_gunzip(char *output, char *image, unsigned long image_len)
s->inptr = 0;
s->bytes_out = 0;

- makecrc();
+ makecrc(s);

if ( gunzip(s) < 0 )
{
diff --git a/xen/common/gzip/inflate.c b/xen/common/gzip/inflate.c
index 8da14880cfbe..dc940e59d853 100644
--- a/xen/common/gzip/inflate.c
+++ b/xen/common/gzip/inflate.c
@@ -1032,16 +1032,12 @@ static int __init inflate(struct gunzip_state *s)
*
**********************************************************************/

-static ulg __initdata crc_32_tab[256];
-static ulg __initdata crc; /* initialized in makecrc() so it'll reside in bss */
-#define CRC_VALUE (crc ^ 0xffffffffUL)
-
/*
* Code to compute the CRC-32 table. Borrowed from
* gzip-1.0.3/makecrc.c.
*/

-static void __init makecrc(void)
+static void __init makecrc(struct gunzip_state *s)
{
/* Not copyrighted 1990 Mark Adler */

@@ -1058,7 +1054,7 @@ static void __init makecrc(void)
for (i = 0; i < sizeof(p)/sizeof(int); i++)
e |= 1L << (31 - p[i]);

- crc_32_tab[0] = 0;
+ s->crc_32_tab[0] = 0;

for (i = 1; i < 256; i++)
{
@@ -1069,11 +1065,11 @@ static void __init makecrc(void)
if (k & 1)
c ^= e;
}
- crc_32_tab[i] = c;
+ s->crc_32_tab[i] = c;
}

/* this is initialized here so this code could reside in ROM */
- crc = (ulg)0xffffffffUL; /* shift register contents */
+ s->crc = (ulg)~0u; /* shift register contents */
}

/* gzip flag byte */
@@ -1189,7 +1185,7 @@ static int __init gunzip(struct gunzip_state *s)
orig_len |= (ulg) NEXTBYTE(s) << 24;

/* Validate decompression */
- if (orig_crc != CRC_VALUE) {
+ if (orig_crc != (s->crc ^ ~0u)) {
error("crc error");
return -1;
}
--
2.30.2