ceph: buffer decoding helpers

Helper for decoding into a ceph_buffer, and other misc decoding helpers
we will need.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
This commit is contained in:
Sage Weil 2010-02-02 16:11:19 -08:00
parent 79788c698b
commit c7e337d649
3 changed files with 53 additions and 0 deletions

View File

@ -1,6 +1,7 @@
#include "ceph_debug.h"
#include "buffer.h"
#include "decode.h"
struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp)
{
@ -59,3 +60,19 @@ int ceph_buffer_alloc(struct ceph_buffer *b, int len, gfp_t gfp)
return 0;
}
int ceph_decode_buffer(struct ceph_buffer **b, void **p, void *end)
{
size_t len;
ceph_decode_need(p, end, sizeof(u32), bad);
len = ceph_decode_32(p);
dout("decode_buffer len %d\n", (int)len);
ceph_decode_need(p, end, len, bad);
*b = ceph_buffer_new(len, GFP_NOFS);
if (!*b)
return -ENOMEM;
ceph_decode_copy(p, (*b)->vec.iov_base, len);
return 0;
bad:
return -EINVAL;
}

View File

@ -34,4 +34,6 @@ static inline void ceph_buffer_put(struct ceph_buffer *b)
kref_put(&b->kref, ceph_buffer_release);
}
extern int ceph_decode_buffer(struct ceph_buffer **b, void **p, void *end);
#endif

View File

@ -2,6 +2,7 @@
#define __CEPH_DECODE_H
#include <asm/unaligned.h>
#include <linux/time.h>
#include "types.h"
@ -65,6 +66,11 @@ static inline void ceph_decode_copy(void **p, void *pv, size_t n)
ceph_decode_need(p, end, sizeof(u16), bad); \
v = ceph_decode_16(p); \
} while (0)
#define ceph_decode_8_safe(p, end, v, bad) \
do { \
ceph_decode_need(p, end, sizeof(u8), bad); \
v = ceph_decode_8(p); \
} while (0)
#define ceph_decode_copy_safe(p, end, pv, n, bad) \
do { \
@ -156,5 +162,33 @@ static inline void ceph_encode_string(void **p, void *end,
*p += len;
}
#define ceph_encode_need(p, end, n, bad) \
do { \
if (unlikely(*(p) + (n) > (end))) \
goto bad; \
} while (0)
#define ceph_encode_64_safe(p, end, v, bad) \
do { \
ceph_encode_need(p, end, sizeof(u64), bad); \
ceph_encode_64(p, v); \
} while (0)
#define ceph_encode_32_safe(p, end, v, bad) \
do { \
ceph_encode_need(p, end, sizeof(u32), bad); \
ceph_encode_32(p, v); \
} while (0)
#define ceph_encode_16_safe(p, end, v, bad) \
do { \
ceph_encode_need(p, end, sizeof(u16), bad); \
ceph_encode_16(p, v); \
} while (0)
#define ceph_encode_copy_safe(p, end, pv, n, bad) \
do { \
ceph_encode_need(p, end, n, bad); \
ceph_encode_copy(p, pv, n); \
} while (0)
#endif