13 #include <netinet/in.h>
15 #include <openssl/sha.h>
19 * Basic data structures for the directory cache
21 * NOTE NOTE NOTE! This is all in the native CPU byte format. It's
22 * not even trying to be portable. It's trying to be efficient. It's
23 * just a cache, after all.
26 #define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
28 unsigned int hdr_signature
;
29 unsigned int hdr_version
;
30 unsigned int hdr_entries
;
31 unsigned char sha1
[20];
35 * The "cache_time" is just the low 32 bits of the
36 * time. It doesn't matter if it overflows - we only
37 * check it for equality in the 32 bits we save.
45 * dev/ino/uid/gid/size are also just tracked to the low 32 bits
46 * Again - this is just a (very strong in practice) heuristic that
47 * the inode hasn't changed.
49 * We save the fields in big-endian order to allow using the
50 * index file over NFS transparently.
53 struct cache_time ce_ctime
;
54 struct cache_time ce_mtime
;
61 unsigned char sha1
[20];
62 unsigned short ce_flags
;
66 #define CE_NAMEMASK (0x0fff)
67 #define CE_STAGE1 (0x1000)
68 #define CE_STAGE2 (0x2000)
70 const char *sha1_file_directory
;
71 struct cache_entry
**active_cache
;
72 unsigned int active_nr
, active_alloc
;
74 #define DB_ENVIRONMENT "SHA1_FILE_DIRECTORY"
75 #define DEFAULT_DB_ENVIRONMENT ".git/objects"
77 #define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
78 #define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
79 #define ce_size(ce) cache_entry_size(ce_namelen(ce))
81 #define alloc_nr(x) (((x)+16)*3/2)
83 /* Initialize and use the cache information */
84 extern int read_cache(void);
85 extern int write_cache(int newfd
, struct cache_entry
**cache
, int entries
);
86 extern int cache_name_pos(const char *name
, int namelen
);
87 extern int add_cache_entry(struct cache_entry
*ce
, int ok_to_add
);
88 extern int remove_file_from_cache(char *path
);
89 extern int cache_match_stat(struct cache_entry
*ce
, struct stat
*st
);
91 #define MTIME_CHANGED 0x0001
92 #define CTIME_CHANGED 0x0002
93 #define OWNER_CHANGED 0x0004
94 #define MODE_CHANGED 0x0008
95 #define INODE_CHANGED 0x0010
96 #define DATA_CHANGED 0x0020
98 /* Return a statically allocated filename matching the sha1 signature */
99 extern char *sha1_file_name(const unsigned char *sha1
);
101 /* Write a memory buffer out to the sha file */
102 extern int write_sha1_buffer(const unsigned char *sha1
, void *buf
, unsigned int size
);
104 /* Read and unpack a sha1 file into memory, write memory to a sha1 file */
105 extern void * map_sha1_file(const unsigned char *sha1
, unsigned long *size
);
106 extern void * unpack_sha1_file(void *map
, unsigned long mapsize
, char *type
, unsigned long *size
);
107 extern void * read_sha1_file(const unsigned char *sha1
, char *type
, unsigned long *size
);
108 extern int write_sha1_file(char *buf
, unsigned len
, unsigned char *return_sha1
);
109 extern int check_sha1_signature(unsigned char *sha1
, void *buf
, unsigned long size
);
111 /* Convert to/from hex/sha1 representation */
112 extern int get_sha1_hex(const char *hex
, unsigned char *sha1
);
113 extern char *sha1_to_hex(const unsigned char *sha1
); /* static buffer result! */
115 /* General helper functions */
116 extern void usage(const char *err
);
117 extern void die(const char *err
, ...);
118 extern int error(const char *err
, ...);
120 extern int cache_name_compare(const char *name1
, int len1
, const char *name2
, int len2
);