git/pack.h

#ifndef PACK_H
#define PACK_H

#include "object.h"
#include "csum-file.h"

struct packed_git;
struct pack_window;
struct repository;

/*
 * Packed object header
 */
#define PACK_SIGNATURE …
#define PACK_VERSION …
#define pack_version_ok(v) …
struct pack_header { … };

/*
 * 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 …

struct pack_idx_option { … };

void reset_pack_idx_option(struct pack_idx_option *);

/*
 * Packed object index header
 */
struct pack_idx_header { … };

/*
 * Common part of object structure used for write_idx_file
 */
struct pack_idx_entry { … };


struct progress;
/* Note, the data argument could be NULL if object type is blob */
verify_fn;

const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects, int nr_objects, const struct pack_idx_option *, const unsigned char *sha1);
int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr);
int verify_pack_index(struct packed_git *);
int verify_pack(struct repository *, struct packed_git *, verify_fn fn, struct progress *, uint32_t);
off_t write_pack_header(struct hashfile *f, uint32_t);
void fixup_pack_header_footer(int, unsigned char *, const char *, uint32_t, unsigned char *, off_t);
char *index_pack_lockfile(int fd, int *is_well_formed);

struct ref;

void write_promisor_file(const char *promisor_name, struct ref **sought, int nr_sought);

char *write_rev_file(const char *rev_name, struct pack_idx_entry **objects, uint32_t nr_objects, const unsigned char *hash, unsigned flags);
char *write_rev_file_order(const char *rev_name, uint32_t *pack_order, uint32_t nr_objects, const unsigned char *hash, unsigned flags);

/*
 * The "hdr" output buffer should be at least this big, which will handle sizes
 * up to 2^67.
 */
#define MAX_PACK_OBJECT_HEADER …
int encode_in_pack_object_header(unsigned char *hdr, int hdr_len,
				 enum object_type, uintmax_t);

#define PH_ERROR_EOF …
#define PH_ERROR_PACK_SIGNATURE …
#define PH_ERROR_PROTOCOL …
int read_pack_header(int fd, struct pack_header *);

struct packing_data;

struct hashfile *create_tmp_packfile(char **pack_tmp_name);
void stage_tmp_packfiles(struct strbuf *name_buffer,
			 const char *pack_tmp_name,
			 struct pack_idx_entry **written_list,
			 uint32_t nr_written,
			 struct packing_data *to_pack,
			 struct pack_idx_option *pack_idx_opts,
			 unsigned char hash[],
			 char **idx_tmp_name);
void rename_tmp_packfile_idx(struct strbuf *basename,
			     char **idx_tmp_name);

#endif