git-commit-vandalism/cache.h
Linus Torvalds 220a0b527b More work on merging with git-read-tree..
Add a "-u" flag to update the tree as a result of a merge.

Right now this code is way too anal about things, and fails merges it
shouldn't, but let me fix up the different cases and this will allow for
much smoother merging even in the presense of dirty data in the working
tree.
2005-06-05 22:07:31 -07:00

230 lines
6.8 KiB
C

#ifndef CACHE_H
#define CACHE_H
#include <unistd.h>
#include <stdio.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <netinet/in.h>
#include SHA1_HEADER
#include <zlib.h>
#if ZLIB_VERNUM < 0x1200
#define deflateBound(c,s) ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
#endif
#ifdef DT_UNKNOWN
#define DTYPE(de) ((de)->d_type)
#else
#define DT_UNKNOWN 0
#define DT_DIR 1
#define DT_REG 2
#define DT_LNK 3
#define DTYPE(de) DT_UNKNOWN
#endif
/*
* Environment variables transition.
* We accept older names for now but warn.
*/
extern char *gitenv_bc(const char *);
#define gitenv(e) (getenv(e) ? : gitenv_bc(e))
/*
* Basic data structures for the directory cache
*/
#define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
struct cache_header {
unsigned int hdr_signature;
unsigned int hdr_version;
unsigned int hdr_entries;
};
/*
* The "cache_time" is just the low 32 bits of the
* time. It doesn't matter if it overflows - we only
* check it for equality in the 32 bits we save.
*/
struct cache_time {
unsigned int sec;
unsigned int nsec;
};
/*
* dev/ino/uid/gid/size are also just tracked to the low 32 bits
* Again - this is just a (very strong in practice) heuristic that
* the inode hasn't changed.
*
* We save the fields in big-endian order to allow using the
* index file over NFS transparently.
*/
struct cache_entry {
struct cache_time ce_ctime;
struct cache_time ce_mtime;
unsigned int ce_dev;
unsigned int ce_ino;
unsigned int ce_mode;
unsigned int ce_uid;
unsigned int ce_gid;
unsigned int ce_size;
unsigned char sha1[20];
unsigned short ce_flags;
char name[0];
};
#define CE_NAMEMASK (0x0fff)
#define CE_STAGEMASK (0x3000)
#define CE_UPDATE (0x4000)
#define CE_STAGESHIFT 12
#define create_ce_flags(len, stage) htons((len) | ((stage) << CE_STAGESHIFT))
#define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
#define ce_size(ce) cache_entry_size(ce_namelen(ce))
#define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
static inline unsigned int create_ce_mode(unsigned int mode)
{
if (S_ISLNK(mode))
return htonl(S_IFLNK);
return htonl(S_IFREG | ce_permissions(mode));
}
#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
extern struct cache_entry **active_cache;
extern unsigned int active_nr, active_alloc, active_cache_changed;
#define GIT_DIR_ENVIRONMENT "GIT_DIR"
#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
extern char *get_object_directory(void);
extern char *get_index_file(void);
#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
#define alloc_nr(x) (((x)+16)*3/2)
/* Initialize and use the cache information */
extern int read_cache(void);
extern int write_cache(int newfd, struct cache_entry **cache, int entries);
extern int cache_name_pos(const char *name, int namelen);
#define ADD_CACHE_OK_TO_ADD 1 /* Ok to add */
#define ADD_CACHE_OK_TO_REPLACE 2 /* Ok to replace file/directory */
extern int add_cache_entry(struct cache_entry *ce, int option);
extern int remove_cache_entry_at(int pos);
extern int remove_file_from_cache(char *path);
extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
extern int ce_match_stat(struct cache_entry *ce, struct stat *st);
extern int index_fd(unsigned char *sha1, int fd, struct stat *st);
extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
struct cache_file {
struct cache_file *next;
char lockfile[PATH_MAX];
};
extern int hold_index_file_for_update(struct cache_file *, const char *path);
extern int commit_index_file(struct cache_file *);
extern void rollback_index_file(struct cache_file *);
#define MTIME_CHANGED 0x0001
#define CTIME_CHANGED 0x0002
#define OWNER_CHANGED 0x0004
#define MODE_CHANGED 0x0008
#define INODE_CHANGED 0x0010
#define DATA_CHANGED 0x0020
#define TYPE_CHANGED 0x0040
/* Return a statically allocated filename matching the sha1 signature */
extern char *sha1_file_name(const unsigned char *sha1);
/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
extern void * map_sha1_file(const unsigned char *sha1, unsigned long *size);
extern int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size);
extern int parse_sha1_header(char *hdr, char *type, unsigned long *sizep);
extern int sha1_delta_base(const unsigned char *, unsigned char *);
extern int sha1_file_size(const unsigned char *, unsigned long *);
extern void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size);
extern void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size);
extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
extern int check_sha1_signature(unsigned char *sha1, void *buf, unsigned long size, const char *type);
/* Read a tree into the cache */
extern int read_tree(void *buffer, unsigned long size, int stage);
extern int write_sha1_from_fd(const unsigned char *sha1, int fd);
extern int has_sha1_file(const unsigned char *sha1);
/* Convert to/from hex/sha1 representation */
extern int get_sha1(const char *str, unsigned char *sha1);
extern int get_sha1_hex(const char *hex, unsigned char *sha1);
extern char *sha1_to_hex(const unsigned char *sha1); /* static buffer result! */
/* General helper functions */
extern void usage(const char *err);
extern void die(const char *err, ...);
extern int error(const char *err, ...);
extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
extern void *read_object_with_reference(const unsigned char *sha1,
const char *required_type,
unsigned long *size,
unsigned char *sha1_ret);
const char *show_date(unsigned long time, int timezone);
void parse_date(char *date, char *buf, int bufsize);
void datestamp(char *buf, int bufsize);
static inline void *xmalloc(size_t size)
{
void *ret = malloc(size);
if (!ret)
die("Out of memory, malloc failed");
return ret;
}
static inline void *xrealloc(void *ptr, size_t size)
{
void *ret = realloc(ptr, size);
if (!ret)
die("Out of memory, realloc failed");
return ret;
}
static inline void *xcalloc(size_t nmemb, size_t size)
{
void *ret = calloc(nmemb, size);
if (!ret)
die("Out of memory, calloc failed");
return ret;
}
struct checkout {
const char *base_dir;
int base_dir_len;
unsigned force:1,
quiet:1,
not_new:1,
refresh_cache:1;
};
extern int checkout_entry(struct cache_entry *ce, struct checkout *state);
#endif /* CACHE_H */