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#ifndef jffs2_private_h
#define jffs2_private_h
#include <jffs2/jffs2.h>
struct b_node {
struct b_node *next;
};
struct b_inode {
struct b_inode *next;
u32 offset; /* physical offset to beginning of real inode */
u32 version;
u32 ino;
u32 isize;
u32 csize;
};
struct b_dirent {
struct b_dirent *next;
u32 offset; /* physical offset to beginning of real dirent */
u32 version;
u32 pino;
u32 ino;
unsigned int nhash;
unsigned char nsize;
unsigned char type;
};
struct b_list {
struct b_node *listTail;
struct b_node *listHead;
unsigned int listCount;
struct mem_block *listMemBase;
};
struct b_lists {
char *partOffset;
struct b_list dir;
struct b_list frag;
};
struct b_compr_info {
u32 num_frags;
u32 compr_sum;
u32 decompr_sum;
};
struct b_jffs2_info {
struct b_compr_info compr_info[JFFS2_NUM_COMPR];
};
static inline int
hdr_crc(struct jffs2_unknown_node *node)
{
#if 1
u32 crc = crc32_no_comp(0, (unsigned char *)node, sizeof(struct jffs2_unknown_node) - 4);
#else
/* what's the semantics of this? why is this here? */
u32 crc = crc32_no_comp(~0, (unsigned char *)node, sizeof(struct jffs2_unknown_node) - 4);
crc ^= ~0;
#endif
if (node->hdr_crc != crc) {
return 0;
} else {
return 1;
}
}
static inline int
dirent_crc(struct jffs2_raw_dirent *node)
{
if (node->node_crc != crc32_no_comp(0, (unsigned char *)node, sizeof(struct jffs2_raw_dirent) - 8)) {
return 0;
} else {
return 1;
}
}
static inline int
dirent_name_crc(struct jffs2_raw_dirent *node)
{
if (node->name_crc != crc32_no_comp(0, (unsigned char *)&(node->name), node->nsize)) {
return 0;
} else {
return 1;
}
}
static inline int
inode_crc(struct jffs2_raw_inode *node)
{
if (node->node_crc != crc32_no_comp(0, (unsigned char *)node, sizeof(struct jffs2_raw_inode) - 8)) {
return 0;
} else {
return 1;
}
}
/* Borrowed from include/linux/dcache.h */
/* Name hashing routines. Initial hash value */
/* Hash courtesy of the R5 hash in reiserfs modulo sign bits */
#define init_name_hash() 0
/* partial hash update function. Assume roughly 4 bits per character */
static inline unsigned long
partial_name_hash(unsigned long c, unsigned long prevhash)
{
return (prevhash + (c << 4) + (c >> 4)) * 11;
}
/*
* Finally: cut down the number of bits to a int value (and try to avoid
* losing bits)
*/
static inline unsigned long end_name_hash(unsigned long hash)
{
return (unsigned int) hash;
}
/* Compute the hash for a name string. */
static inline unsigned int
full_name_hash(const unsigned char *name, unsigned int len)
{
unsigned long hash = init_name_hash();
while (len--)
hash = partial_name_hash(*name++, hash);
return end_name_hash(hash);
}
#endif /* jffs2_private.h */
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