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#ifndef PACK_H
#define PACK_H
#include "object.h"
/*
* Packed object header
*/
#define PACK_SIGNATURE 0x5041434b /* "PACK" */
#define PACK_VERSION 2
#define pack_version_ok(v) ((v) == htonl(2) || (v) == htonl(3))
struct pack_header {
uint32_t hdr_signature;
uint32_t hdr_version;
uint32_t hdr_entries;
};
/*
* The first four bytes of index formats later than version 1 should
* start with this signature, as all older git binaries would find this
* value illegal and abort reading the file.
*
* This is the case because the number of objects in a packfile
* cannot exceed 1,431,660,000 as every object would need at least
* 3 bytes of data and the overall packfile cannot exceed 4 GiB with
* version 1 of the index file due to the offsets limited to 32 bits.
* Clearly the signature exceeds this maximum.
*
* Very old git binaries will also compare the first 4 bytes to the
* next 4 bytes in the index and abort with a "non-monotonic index"
* error if the second 4 byte word is smaller than the first 4
* byte word. This would be true in the proposed future index
* format as idx_signature would be greater than idx_version.
*/
#define PACK_IDX_SIGNATURE 0xff744f63 /* "\377tOc" */
struct pack_idx_option {
unsigned flags;
/* flag bits */
#define WRITE_IDX_VERIFY 01 /* verify only, do not write the idx file */
#define WRITE_IDX_STRICT 02
uint32_t version;
uint32_t off32_limit;
/*
* List of offsets that would fit within off32_limit but
* need to be written out as 64-bit entity for byte-for-byte
* verification.
*/
int anomaly_alloc, anomaly_nr;
uint32_t *anomaly;
};
extern void reset_pack_idx_option(struct pack_idx_option *);
/*
* Packed object index header
*/
struct pack_idx_header {
uint32_t idx_signature;
uint32_t idx_version;
};
/*
* Common part of object structure used for write_idx_file
*/
struct pack_idx_entry {
unsigned char sha1[20];
uint32_t crc32;
off_t offset;
};
struct progress;
typedef int (*verify_fn)(const unsigned char*, enum object_type, unsigned long, void*, int*);
extern const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects, int nr_objects, const struct pack_idx_option *, unsigned char *sha1);
extern int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr);
extern int verify_pack_index(struct packed_git *);
extern int verify_pack(struct packed_git *, verify_fn fn, struct progress *, uint32_t);
extern void fixup_pack_header_footer(int, unsigned char *, const char *, uint32_t, unsigned char *, off_t);
extern char *index_pack_lockfile(int fd);
extern int encode_in_pack_object_header(enum object_type, uintmax_t, unsigned char *);
#define PH_ERROR_EOF (-1)
#define PH_ERROR_PACK_SIGNATURE (-2)
#define PH_ERROR_PROTOCOL (-3)
extern int read_pack_header(int fd, struct pack_header *);
#endif
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