[thirdparty/git.git] / cache.h

#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 <sys/types.h>
#include <dirent.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

#ifdef __GNUC__
#define NORETURN __attribute__((__noreturn__))
#else
#define NORETURN
#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_refs_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 */
#define ADD_CACHE_SKIP_DFCHECK 4	/* Ok to skip DF conflict checks */
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_object_info(const unsigned char *, 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(const 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_pack(const unsigned char *sha1);
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) NORETURN;
extern void die(const char *err, ...) NORETURN;
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);

extern struct alternate_object_database {
	char *base;
	char *name;
} *alt_odb;
extern void prepare_alt_odb(void);

extern struct packed_git {
	struct packed_git *next;
	unsigned long index_size;
	unsigned long pack_size;
	unsigned int *index_base;
	void *pack_base;
	unsigned int pack_last_used;
	unsigned int pack_use_cnt;
	char pack_name[0]; /* something like ".git/objects/pack/xxxxx.pack" */
} *packed_git;

struct pack_entry {
	unsigned int offset;
	unsigned char sha1[20];
	struct packed_git *p;
};

extern void prepare_packed_git(void);
extern int use_packed_git(struct packed_git *);
extern void unuse_packed_git(struct packed_git *);
extern struct packed_git *add_packed_git(char *, int);
extern int num_packed_objects(const struct packed_git *p);
extern int nth_packed_object_sha1(const struct packed_git *, int, unsigned char*);
extern int find_pack_entry_one(const unsigned char *, struct pack_entry *, struct packed_git *);
extern void *unpack_entry_gently(struct pack_entry *, char *, unsigned long *);
extern void packed_object_info_detail(struct pack_entry *, char *, unsigned long *, unsigned long *, int *, unsigned char *);

#endif /* CACHE_H */
Commit	Line	Data
e83c5163 LT	1	#ifndef CACHE_H
	2	#define CACHE_H
	3
2dee0609	4	#include <unistd.h>
e83c5163 LT	5	#include <stdio.h>
	6	#include <sys/stat.h>
	7	#include <fcntl.h>
	8	#include <stddef.h>
	9	#include <stdlib.h>
	10	#include <stdarg.h>
bf0c6e83	11	#include <string.h>
e83c5163	12	#include <errno.h>
6b0c3121	13	#include <limits.h>
e83c5163	14	#include <sys/mman.h>
bb233d69	15	#include <sys/param.h>
ccc4feb5	16	#include <netinet/in.h>
575f4974 LT	17	#include <sys/types.h>
575f4974 LT	18	#include <dirent.h>
e83c5163	19
cef661fc	20	#include SHA1_HEADER
e83c5163 LT	21	#include <zlib.h>
e83c5163 LT	22
9da3acfb ET	23	#if ZLIB_VERNUM < 0x1200
	24	#define deflateBound(c,s) ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
	25	#endif
	26
b6829693 ET	27	#ifdef DT_UNKNOWN
	28	#define DTYPE(de) ((de)->d_type)
	29	#else
	30	#define DT_UNKNOWN 0
	31	#define DT_DIR 1
	32	#define DT_REG 2
a15c1c60	33	#define DT_LNK 3
b6829693 ET	34	#define DTYPE(de) DT_UNKNOWN
	35	#endif
	36
90334cf7 LT	37	#ifdef __GNUC__
	38	#define NORETURN __attribute__((__noreturn__))
	39	#else
	40	#define NORETURN
	41	#endif
	42
d19938ab JH	43	/*
	44	* Environment variables transition.
	45	* We accept older names for now but warn.
	46	*/
	47	extern char gitenv_bc(const char );
	48	#define gitenv(e) (getenv(e) ? : gitenv_bc(e))
	49
e83c5163 LT	50	/*
e83c5163 LT	51	* Basic data structures for the directory cache
e83c5163 LT	52	*/
	53
	54	#define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
	55	struct cache_header {
ccc4feb5 LT	56	unsigned int hdr_signature;
	57	unsigned int hdr_version;
	58	unsigned int hdr_entries;
e83c5163 LT	59	};
	60
	61	/*
	62	* The "cache_time" is just the low 32 bits of the
	63	* time. It doesn't matter if it overflows - we only
	64	* check it for equality in the 32 bits we save.
	65	*/
	66	struct cache_time {
	67	unsigned int sec;
	68	unsigned int nsec;
	69	};
	70
	71	/*
	72	* dev/ino/uid/gid/size are also just tracked to the low 32 bits
	73	* Again - this is just a (very strong in practice) heuristic that
	74	* the inode hasn't changed.
ccc4feb5 LT	75	*
	76	* We save the fields in big-endian order to allow using the
	77	* index file over NFS transparently.
e83c5163 LT	78	*/
e83c5163 LT	79	struct cache_entry {
ccc4feb5 LT	80	struct cache_time ce_ctime;
	81	struct cache_time ce_mtime;
	82	unsigned int ce_dev;
	83	unsigned int ce_ino;
	84	unsigned int ce_mode;
	85	unsigned int ce_uid;
	86	unsigned int ce_gid;
	87	unsigned int ce_size;
e83c5163	88	unsigned char sha1[20];
f5cabd13	89	unsigned short ce_flags;
59c1e249	90	char name[0];
e83c5163 LT	91	};
e83c5163 LT	92
95fd5bf8 LT	93	#define CE_NAMEMASK (0x0fff)
95fd5bf8 LT	94	#define CE_STAGEMASK (0x3000)
220a0b52	95	#define CE_UPDATE (0x4000)
aee46198	96	#define CE_STAGESHIFT 12
95fd5bf8	97
aee46198 JH	98	#define create_ce_flags(len, stage) htons((len) \| ((stage) << CE_STAGESHIFT))
	99	#define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
	100	#define ce_size(ce) cache_entry_size(ce_namelen(ce))
	101	#define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
	102
e4479470	103	#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
8ae0a8c5 KS	104	static inline unsigned int create_ce_mode(unsigned int mode)
8ae0a8c5 KS	105	{
8ae0a8c5 KS	106	if (S_ISLNK(mode))
8ae0a8c5 KS	107	return htonl(S_IFLNK);
db823d4a	108	return htonl(S_IFREG \| ce_permissions(mode));
8ae0a8c5	109	}
e4479470	110
aee46198	111	#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
f5cabd13	112
88355048 PB	113	extern struct cache_entry **active_cache;
88355048 PB	114	extern unsigned int active_nr, active_alloc, active_cache_changed;
e83c5163	115
8ac069ac JH	116	#define GIT_DIR_ENVIRONMENT "GIT_DIR"
8ac069ac JH	117	#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
d19938ab	118	#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
bb233d69	119	#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
bb233d69	120
8ac069ac	121	extern char *get_object_directory(void);
95fc7512	122	extern char *get_refs_directory(void);
8ac069ac JH	123	extern char *get_index_file(void);
	124
	125	#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
bb233d69	126
e83c5163 LT	127	#define alloc_nr(x) (((x)+16)*3/2)
e83c5163 LT	128
734aab75	129	/* Initialize and use the cache information */
e83c5163	130	extern int read_cache(void);
197ee8c9	131	extern int write_cache(int newfd, struct cache_entry **cache, int entries);
eb38c22f	132	extern int cache_name_pos(const char *name, int namelen);
192268c1 JH	133	#define ADD_CACHE_OK_TO_ADD 1 /* Ok to add */
192268c1 JH	134	#define ADD_CACHE_OK_TO_REPLACE 2 /* Ok to replace file/directory */
b155725d	135	#define ADD_CACHE_SKIP_DFCHECK 4 /* Ok to skip DF conflict checks */
192268c1	136	extern int add_cache_entry(struct cache_entry *ce, int option);
dbbce55b	137	extern int remove_cache_entry_at(int pos);
197ee8c9	138	extern int remove_file_from_cache(char *path);
dbbce55b	139	extern int ce_same_name(struct cache_entry a, struct cache_entry b);
5d728c84	140	extern int ce_match_stat(struct cache_entry ce, struct stat st);
74400e71	141	extern int index_fd(unsigned char sha1, int fd, struct stat st);
415e96c8 JH	142	extern void fill_stat_cache_info(struct cache_entry ce, struct stat st);
	143
	144	struct cache_file {
	145	struct cache_file *next;
	146	char lockfile[PATH_MAX];
	147	};
	148	extern int hold_index_file_for_update(struct cache_file , const char path);
	149	extern int commit_index_file(struct cache_file *);
	150	extern void rollback_index_file(struct cache_file *);
734aab75 LT	151
	152	#define MTIME_CHANGED 0x0001
	153	#define CTIME_CHANGED 0x0002
	154	#define OWNER_CHANGED 0x0004
	155	#define MODE_CHANGED 0x0008
	156	#define INODE_CHANGED 0x0010
	157	#define DATA_CHANGED 0x0020
8ae0a8c5	158	#define TYPE_CHANGED 0x0040
e83c5163 LT	159
e83c5163 LT	160	/* Return a statically allocated filename matching the sha1 signature */
73134b6d	161	extern char sha1_file_name(const unsigned char sha1);
e83c5163	162
e83c5163	163	/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
73134b6d	164	extern void * map_sha1_file(const unsigned char sha1, unsigned long size);
c4483576	165	extern int unpack_sha1_header(z_stream stream, void map, unsigned long mapsize, void *buffer, unsigned long size);
5180cacc	166	extern int parse_sha1_header(char hdr, char type, unsigned long *sizep);
36e4d74a	167	extern int sha1_object_info(const unsigned char , char , unsigned long *);
2ade9340	168	extern void * unpack_sha1_file(void map, unsigned long mapsize, char type, unsigned long *size);
73134b6d	169	extern void * read_sha1_file(const unsigned char sha1, char type, unsigned long *size);
bf0f910d	170	extern int write_sha1_file(void buf, unsigned long len, const char type, unsigned char *return_sha1);
8237b185	171
5d6ccf5c	172	extern int check_sha1_signature(const unsigned char sha1, void buf, unsigned long size, const char *type);
e83c5163	173
94537c78 LT	174	/* Read a tree into the cache */
	175	extern int read_tree(void *buffer, unsigned long size, int stage);
	176
8237b185 DB	177	extern int write_sha1_from_fd(const unsigned char *sha1, int fd);
8237b185 DB	178
dade09c2	179	extern int has_sha1_pack(const unsigned char *sha1);
8237b185 DB	180	extern int has_sha1_file(const unsigned char *sha1);
8237b185 DB	181
e83c5163	182	/* Convert to/from hex/sha1 representation */
3c249c95	183	extern int get_sha1(const char str, unsigned char sha1);
197ee8c9 LT	184	extern int get_sha1_hex(const char hex, unsigned char sha1);
197ee8c9 LT	185	extern char sha1_to_hex(const unsigned char sha1); /* static buffer result! */
e83c5163 LT	186
e83c5163 LT	187	/* General helper functions */
90334cf7 LT	188	extern void usage(const char *err) NORETURN;
90334cf7 LT	189	extern void die(const char *err, ...) NORETURN;
2de381f9 PB	190	extern int error(const char *err, ...);
2de381f9 PB	191
958ba6c9	192	extern int base_name_compare(const char name1, int len1, int mode1, const char name2, int len2, int mode2);
79517a06	193	extern int cache_name_compare(const char name1, int len1, const char name2, int len2);
e83c5163	194
40469ee9	195	extern void read_object_with_reference(const unsigned char sha1,
bf0f910d	196	const char *required_type,
40469ee9 JH	197	unsigned long *size,
40469ee9 JH	198	unsigned char *sha1_ret);
f4913f91	199
f80cd783	200	const char *show_date(unsigned long time, int timezone);
ecee9d9e ET	201	void parse_date(char date, char buf, int bufsize);
	202	void datestamp(char *buf, int bufsize);
	203
127cfd0d	204	static inline void *xmalloc(size_t size)
812666c8 CL	205	{
	206	void *ret = malloc(size);
	207	if (!ret)
	208	die("Out of memory, malloc failed");
	209	return ret;
	210	}
	211
127cfd0d	212	static inline void xrealloc(void ptr, size_t size)
812666c8 CL	213	{
	214	void *ret = realloc(ptr, size);
	215	if (!ret)
	216	die("Out of memory, realloc failed");
	217	return ret;
	218	}
	219
127cfd0d BR	220	static inline void *xcalloc(size_t nmemb, size_t size)
	221	{
	222	void *ret = calloc(nmemb, size);
	223	if (!ret)
	224	die("Out of memory, calloc failed");
	225	return ret;
	226	}
	227
12dccc16 LT	228	struct checkout {
	229	const char *base_dir;
	230	int base_dir_len;
	231	unsigned force:1,
	232	quiet:1,
	233	not_new:1,
	234	refresh_cache:1;
	235	};
	236
	237	extern int checkout_entry(struct cache_entry ce, struct checkout state);
	238
9a217f2a JH	239	extern struct alternate_object_database {
	240	char *base;
	241	char *name;
	242	} *alt_odb;
	243	extern void prepare_alt_odb(void);
	244
	245	extern struct packed_git {
	246	struct packed_git *next;
	247	unsigned long index_size;
	248	unsigned long pack_size;
	249	unsigned int *index_base;
	250	void *pack_base;
	251	unsigned int pack_last_used;
f9253394	252	unsigned int pack_use_cnt;
9a217f2a JH	253	char pack_name[0]; /* something like ".git/objects/pack/xxxxx.pack" */
9a217f2a JH	254	} *packed_git;
f3bf9224 JH	255
	256	struct pack_entry {
	257	unsigned int offset;
	258	unsigned char sha1[20];
	259	struct packed_git *p;
	260	};
	261
9a217f2a	262	extern void prepare_packed_git(void);
f9253394 JH	263	extern int use_packed_git(struct packed_git *);
	264	extern void unuse_packed_git(struct packed_git *);
	265	extern struct packed_git add_packed_git(char , int);
9a217f2a JH	266	extern int num_packed_objects(const struct packed_git *p);
9a217f2a JH	267	extern int nth_packed_object_sha1(const struct packed_git , int, unsigned char);
f3bf9224 JH	268	extern int find_pack_entry_one(const unsigned char , struct pack_entry , struct packed_git *);
f3bf9224 JH	269	extern void unpack_entry_gently(struct pack_entry , char , unsigned long );
ad8c80a5	270	extern void packed_object_info_detail(struct pack_entry , char , unsigned long , unsigned long , int , unsigned char );
9a217f2a	271
e83c5163	272	#endif /* CACHE_H */