mirror of
https://github.com/git/git.git
synced 2024-11-25 10:54:00 +08:00
6c52614864
It is useful to be able to rewind a check-summed file to a certain previous state after writing data into it using sha1write() API. The fast-import command does this after streaming a blob data to the packfile being generated and then noticing that the same blob has already been written, and it does this with a private code truncate_pack() that is commented as "Yes, this is a layering violation". Introduce two API functions, sha1file_checkpoint(), that allows the caller to save a state of a sha1file, and then later revert it to the saved state. Use it to reimplement truncate_pack(). Signed-off-by: Junio C Hamano <gitster@pobox.com>
43 lines
1.1 KiB
C
43 lines
1.1 KiB
C
#ifndef CSUM_FILE_H
|
|
#define CSUM_FILE_H
|
|
|
|
struct progress;
|
|
|
|
/* A SHA1-protected file */
|
|
struct sha1file {
|
|
int fd;
|
|
int check_fd;
|
|
unsigned int offset;
|
|
git_SHA_CTX ctx;
|
|
off_t total;
|
|
struct progress *tp;
|
|
const char *name;
|
|
int do_crc;
|
|
uint32_t crc32;
|
|
unsigned char buffer[8192];
|
|
};
|
|
|
|
/* Checkpoint */
|
|
struct sha1file_checkpoint {
|
|
off_t offset;
|
|
git_SHA_CTX ctx;
|
|
};
|
|
|
|
extern void sha1file_checkpoint(struct sha1file *, struct sha1file_checkpoint *);
|
|
extern int sha1file_truncate(struct sha1file *, struct sha1file_checkpoint *);
|
|
|
|
/* sha1close flags */
|
|
#define CSUM_CLOSE 1
|
|
#define CSUM_FSYNC 2
|
|
|
|
extern struct sha1file *sha1fd(int fd, const char *name);
|
|
extern struct sha1file *sha1fd_check(const char *name);
|
|
extern struct sha1file *sha1fd_throughput(int fd, const char *name, struct progress *tp);
|
|
extern int sha1close(struct sha1file *, unsigned char *, unsigned int);
|
|
extern int sha1write(struct sha1file *, void *, unsigned int);
|
|
extern void sha1flush(struct sha1file *f);
|
|
extern void crc32_begin(struct sha1file *);
|
|
extern uint32_t crc32_end(struct sha1file *);
|
|
|
|
#endif
|