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git/cache.h
Shawn O. Pearce c9ced051c3 Fix random fast-import errors when compiled with NO_MMAP
fast-import was relying on the fact that on most systems mmap() and
write() are synchronized by the filesystem's buffer cache.  We were
relying on the ability to mmap() 20 bytes beyond the current end
of the file, then later fill in those bytes with a future write()
call, then read them through the previously obtained mmap() address.

This isn't always true with some implementations of NFS, but it is
especially not true with our NO_MMAP=YesPlease build time option used
on some platforms.  If fast-import was built with NO_MMAP=YesPlease
we used the malloc()+pread() emulation and the subsequent write()
call does not update the trailing 20 bytes of a previously obtained
"mmap()" (aka malloc'd) address.

Under NO_MMAP that behavior causes unpack_entry() in sha1_file.c to
be unable to read an object header (or data) that has been unlucky
enough to be written to the packfile at a location such that it
is in the trailing 20 bytes of a window previously opened on that
same packfile.

This bug has gone unnoticed for a very long time as it is highly data
dependent.  Not only does the object have to be placed at the right
position, but it also needs to be positioned behind some other object
that has been accessed due to a branch cache invalidation.  In other
words the stars had to align just right, and if you did run into
this bug you probably should also have purchased a lottery ticket.

Fortunately the workaround is a lot easier than the bug explanation.

Before we allow unpack_entry() to read data from a pack window
that has also (possibly) been modified through write() we force
all existing windows on that packfile to be closed.  By closing
the windows we ensure that any new access via the emulated mmap()
will reread the packfile, updating to the current file content.

This comes at a slight performance degredation as we cannot reuse
previously cached windows when we update the packfile.  But it
is a fairly minor difference as the window closes happen at only
two points:

 - When the packfile is finalized and its .idx is generated:

   At this stage we are getting ready to update the refs and any
   data access into the packfile is going to be random, and is
   going after only the branch tips (to ensure they are valid).
   Our existing windows (if any) are not likely to be positioned
   at useful locations to access those final tip commits so we
   probably were closing them before anyway.

 - When the branch cache missed and we need to reload:

   At this point fast-import is getting change commands for the next
   commit and it needs to go re-read a tree object it previously
   had written out to the packfile.  What windows we had (if any)
   are not likely to cover the tree in question so we probably were
   closing them before anyway.

We do try to avoid unnecessarily closing windows in the second case
by checking to see if the packfile size has increased since the
last time we called unpack_entry() on that packfile.  If the size
has not changed then we have not written additional data, and any
existing window is still vaild.  This nicely handles the cases where
fast-import is going through a branch cache reload and needs to read
many trees at once.  During such an event we are not likely to be
updating the packfile so we do not cycle the windows between reads.

With this change in place t9301-fast-export.sh (which was broken
by c3b0dec509) finally works again.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-01-17 22:39:20 -08:00

669 lines
23 KiB
C

#ifndef CACHE_H
#define CACHE_H
#include "git-compat-util.h"
#include "strbuf.h"
#include SHA1_HEADER
#include <zlib.h>
#if defined(NO_DEFLATE_BOUND) || ZLIB_VERNUM < 0x1200
#define deflateBound(c,s) ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
#endif
#if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
#define DTYPE(de) ((de)->d_type)
#else
#undef DT_UNKNOWN
#undef DT_DIR
#undef DT_REG
#undef DT_LNK
#define DT_UNKNOWN 0
#define DT_DIR 1
#define DT_REG 2
#define DT_LNK 3
#define DTYPE(de) DT_UNKNOWN
#endif
/* unknown mode (impossible combination S_IFIFO|S_IFCHR) */
#define S_IFINVALID 0030000
/*
* A "directory link" is a link to another git directory.
*
* The value 0160000 is not normally a valid mode, and
* also just happens to be S_IFDIR + S_IFLNK
*
* NOTE! We *really* shouldn't depend on the S_IFxxx macros
* always having the same values everywhere. We should use
* our internal git values for these things, and then we can
* translate that to the OS-specific value. It just so
* happens that everybody shares the same bit representation
* in the UNIX world (and apparently wider too..)
*/
#define S_IFGITLINK 0160000
#define S_ISGITLINK(m) (((m) & S_IFMT) == S_IFGITLINK)
/*
* Intensive research over the course of many years has shown that
* port 9418 is totally unused by anything else. Or
*
* Your search - "port 9418" - did not match any documents.
*
* as www.google.com puts it.
*
* This port has been properly assigned for git use by IANA:
* git (Assigned-9418) [I06-050728-0001].
*
* git 9418/tcp git pack transfer service
* git 9418/udp git pack transfer service
*
* with Linus Torvalds <torvalds@osdl.org> as the point of
* contact. September 2005.
*
* See http://www.iana.org/assignments/port-numbers
*/
#define DEFAULT_GIT_PORT 9418
/*
* 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[FLEX_ARRAY]; /* more */
};
#define CE_NAMEMASK (0x0fff)
#define CE_STAGEMASK (0x3000)
#define CE_UPDATE (0x4000)
#define CE_VALID (0x8000)
#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);
if (S_ISDIR(mode) || S_ISGITLINK(mode))
return htonl(S_IFGITLINK);
return htonl(S_IFREG | ce_permissions(mode));
}
static inline unsigned int ce_mode_from_stat(struct cache_entry *ce, unsigned int mode)
{
extern int trust_executable_bit, has_symlinks;
if (!has_symlinks && S_ISREG(mode) &&
ce && S_ISLNK(ntohl(ce->ce_mode)))
return ce->ce_mode;
if (!trust_executable_bit && S_ISREG(mode)) {
if (ce && S_ISREG(ntohl(ce->ce_mode)))
return ce->ce_mode;
return create_ce_mode(0666);
}
return create_ce_mode(mode);
}
#define canon_mode(mode) \
(S_ISREG(mode) ? (S_IFREG | ce_permissions(mode)) : \
S_ISLNK(mode) ? S_IFLNK : S_ISDIR(mode) ? S_IFDIR : S_IFGITLINK)
#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
struct index_state {
struct cache_entry **cache;
unsigned int cache_nr, cache_alloc, cache_changed;
struct cache_tree *cache_tree;
time_t timestamp;
void *mmap;
size_t mmap_size;
};
extern struct index_state the_index;
#ifndef NO_THE_INDEX_COMPATIBILITY_MACROS
#define active_cache (the_index.cache)
#define active_nr (the_index.cache_nr)
#define active_alloc (the_index.cache_alloc)
#define active_cache_changed (the_index.cache_changed)
#define active_cache_tree (the_index.cache_tree)
#define read_cache() read_index(&the_index)
#define read_cache_from(path) read_index_from(&the_index, (path))
#define write_cache(newfd, cache, entries) write_index(&the_index, (newfd))
#define discard_cache() discard_index(&the_index)
#define cache_name_pos(name, namelen) index_name_pos(&the_index,(name),(namelen))
#define add_cache_entry(ce, option) add_index_entry(&the_index, (ce), (option))
#define remove_cache_entry_at(pos) remove_index_entry_at(&the_index, (pos))
#define remove_file_from_cache(path) remove_file_from_index(&the_index, (path))
#define add_file_to_cache(path, verbose) add_file_to_index(&the_index, (path), (verbose))
#define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL)
#define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
#define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
#endif
enum object_type {
OBJ_BAD = -1,
OBJ_NONE = 0,
OBJ_COMMIT = 1,
OBJ_TREE = 2,
OBJ_BLOB = 3,
OBJ_TAG = 4,
/* 5 for future expansion */
OBJ_OFS_DELTA = 6,
OBJ_REF_DELTA = 7,
OBJ_MAX,
};
static inline enum object_type object_type(unsigned int mode)
{
return S_ISDIR(mode) ? OBJ_TREE :
S_ISGITLINK(mode) ? OBJ_COMMIT :
OBJ_BLOB;
}
#define GIT_DIR_ENVIRONMENT "GIT_DIR"
#define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
#define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
#define CONFIG_ENVIRONMENT "GIT_CONFIG"
#define CONFIG_LOCAL_ENVIRONMENT "GIT_CONFIG_LOCAL"
#define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
#define GITATTRIBUTES_FILE ".gitattributes"
#define INFOATTRIBUTES_FILE "info/attributes"
#define ATTRIBUTE_MACRO_PREFIX "[attr]"
extern int is_bare_repository_cfg;
extern int is_bare_repository(void);
extern int is_inside_git_dir(void);
extern char *git_work_tree_cfg;
extern int is_inside_work_tree(void);
extern const char *get_git_dir(void);
extern char *get_object_directory(void);
extern char *get_refs_directory(void);
extern char *get_index_file(void);
extern char *get_graft_file(void);
extern int set_git_dir(const char *path);
extern const char *get_git_work_tree(void);
#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
extern const char **get_pathspec(const char *prefix, const char **pathspec);
extern void setup_work_tree(void);
extern const char *setup_git_directory_gently(int *);
extern const char *setup_git_directory(void);
extern const char *prefix_path(const char *prefix, int len, const char *path);
extern const char *prefix_filename(const char *prefix, int len, const char *path);
extern void verify_filename(const char *prefix, const char *name);
extern void verify_non_filename(const char *prefix, const char *name);
#define alloc_nr(x) (((x)+16)*3/2)
/*
* Realloc the buffer pointed at by variable 'x' so that it can hold
* at least 'nr' entries; the number of entries currently allocated
* is 'alloc', using the standard growing factor alloc_nr() macro.
*
* DO NOT USE any expression with side-effect for 'x' or 'alloc'.
*/
#define ALLOC_GROW(x, nr, alloc) \
do { \
if ((nr) > alloc) { \
if (alloc_nr(alloc) < (nr)) \
alloc = (nr); \
else \
alloc = alloc_nr(alloc); \
x = xrealloc((x), alloc * sizeof(*(x))); \
} \
} while(0)
/* Initialize and use the cache information */
extern int read_index(struct index_state *);
extern int read_index_from(struct index_state *, const char *path);
extern int write_index(struct index_state *, int newfd);
extern int discard_index(struct index_state *);
extern int verify_path(const char *path);
extern int index_name_pos(struct index_state *, 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 */
#define ADD_CACHE_JUST_APPEND 8 /* Append only; tree.c::read_tree() */
extern int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
extern struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
extern int remove_index_entry_at(struct index_state *, int pos);
extern int remove_file_from_index(struct index_state *, const char *path);
extern int add_file_to_index(struct index_state *, const char *path, int verbose);
extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, int refresh);
extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
/* do stat comparison even if CE_VALID is true */
#define CE_MATCH_IGNORE_VALID 01
/* do not check the contents but report dirty on racily-clean entries */
#define CE_MATCH_RACY_IS_DIRTY 02
extern int ie_match_stat(struct index_state *, struct cache_entry *, struct stat *, unsigned int);
extern int ie_modified(struct index_state *, struct cache_entry *, struct stat *, unsigned int);
extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, enum object_type type, const char *path);
extern int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object);
extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
#define REFRESH_REALLY 0x0001 /* ignore_valid */
#define REFRESH_UNMERGED 0x0002 /* allow unmerged */
#define REFRESH_QUIET 0x0004 /* be quiet about it */
#define REFRESH_IGNORE_MISSING 0x0008 /* ignore non-existent */
extern int refresh_index(struct index_state *, unsigned int flags, const char **pathspec, char *seen);
struct lock_file {
struct lock_file *next;
int fd;
pid_t owner;
char on_list;
char filename[PATH_MAX];
};
extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
extern int commit_lock_file(struct lock_file *);
extern int hold_locked_index(struct lock_file *, int);
extern int commit_locked_index(struct lock_file *);
extern void set_alternate_index_output(const char *);
extern int close_lock_file(struct lock_file *);
extern void rollback_lock_file(struct lock_file *);
extern int delete_ref(const char *, const unsigned char *sha1);
/* Environment bits from configuration mechanism */
extern int trust_executable_bit;
extern int quote_path_fully;
extern int has_symlinks;
extern int assume_unchanged;
extern int prefer_symlink_refs;
extern int log_all_ref_updates;
extern int warn_ambiguous_refs;
extern int shared_repository;
extern const char *apply_default_whitespace;
extern int zlib_compression_level;
extern int core_compression_level;
extern int core_compression_seen;
extern size_t packed_git_window_size;
extern size_t packed_git_limit;
extern size_t delta_base_cache_limit;
extern int auto_crlf;
#define GIT_REPO_VERSION 0
extern int repository_format_version;
extern int check_repository_format(void);
#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 *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
extern char *sha1_file_name(const unsigned char *sha1);
extern char *sha1_pack_name(const unsigned char *sha1);
extern char *sha1_pack_index_name(const unsigned char *sha1);
extern const char *find_unique_abbrev(const unsigned char *sha1, int);
extern const unsigned char null_sha1[20];
static inline int is_null_sha1(const unsigned char *sha1)
{
return !memcmp(sha1, null_sha1, 20);
}
static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
{
return memcmp(sha1, sha2, 20);
}
static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
{
memcpy(sha_dst, sha_src, 20);
}
static inline void hashclr(unsigned char *hash)
{
memset(hash, 0, 20);
}
int git_mkstemp(char *path, size_t n, const char *template);
enum sharedrepo {
PERM_UMASK = 0,
PERM_GROUP,
PERM_EVERYBODY
};
int git_config_perm(const char *var, const char *value);
int adjust_shared_perm(const char *path);
int safe_create_leading_directories(char *path);
char *enter_repo(char *path, int strict);
static inline int is_absolute_path(const char *path)
{
return path[0] == '/';
}
const char *make_absolute_path(const char *path);
/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
extern int sha1_object_info(const unsigned char *, unsigned long *);
extern void * read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size);
extern int hash_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1);
extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
extern int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
size_t bufsize, size_t *bufposn);
extern int write_sha1_to_fd(int fd, const unsigned char *sha1);
extern int move_temp_to_file(const char *tmpfile, const char *filename);
extern int has_sha1_pack(const unsigned char *sha1, const char **ignore);
extern int has_sha1_file(const unsigned char *sha1);
extern int has_pack_file(const unsigned char *sha1);
extern int has_pack_index(const unsigned char *sha1);
extern const signed char hexval_table[256];
static inline unsigned int hexval(unsigned char c)
{
return hexval_table[c];
}
/* Convert to/from hex/sha1 representation */
#define MINIMUM_ABBREV 4
#define DEFAULT_ABBREV 7
extern int get_sha1(const char *str, unsigned char *sha1);
extern int get_sha1_with_mode(const char *str, unsigned char *sha1, unsigned *mode);
extern int get_sha1_hex(const char *hex, unsigned char *sha1);
extern char *sha1_to_hex(const unsigned char *sha1); /* static buffer result! */
extern int read_ref(const char *filename, unsigned char *sha1);
extern const char *resolve_ref(const char *path, unsigned char *sha1, int, int *);
extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
extern int refname_match(const char *abbrev_name, const char *full_name, const char **rules);
extern const char *ref_rev_parse_rules[];
extern const char *ref_fetch_rules[];
extern int create_symref(const char *ref, const char *refs_heads_master, const char *logmsg);
extern int validate_headref(const char *ref);
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);
enum date_mode {
DATE_NORMAL = 0,
DATE_RELATIVE,
DATE_SHORT,
DATE_LOCAL,
DATE_ISO8601,
DATE_RFC2822
};
const char *show_date(unsigned long time, int timezone, enum date_mode mode);
int parse_date(const char *date, char *buf, int bufsize);
void datestamp(char *buf, int bufsize);
unsigned long approxidate(const char *);
enum date_mode parse_date_format(const char *format);
#define IDENT_WARN_ON_NO_NAME 1
#define IDENT_ERROR_ON_NO_NAME 2
#define IDENT_NO_DATE 4
extern const char *git_author_info(int);
extern const char *git_committer_info(int);
extern const char *fmt_ident(const char *name, const char *email, const char *date_str, int);
extern const char *fmt_name(const char *name, const char *email);
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, const struct checkout *state, char *topath);
extern int has_symlink_leading_path(const char *name, char *last_symlink);
extern struct alternate_object_database {
struct alternate_object_database *next;
char *name;
char base[FLEX_ARRAY]; /* more */
} *alt_odb_list;
extern void prepare_alt_odb(void);
struct pack_window {
struct pack_window *next;
unsigned char *base;
off_t offset;
size_t len;
unsigned int last_used;
unsigned int inuse_cnt;
};
extern struct packed_git {
struct packed_git *next;
struct pack_window *windows;
off_t pack_size;
const void *index_data;
size_t index_size;
uint32_t num_objects;
int index_version;
time_t mtime;
int pack_fd;
int pack_local;
unsigned char sha1[20];
/* something like ".git/objects/pack/xxxxx.pack" */
char pack_name[FLEX_ARRAY]; /* more */
} *packed_git;
struct pack_entry {
off_t offset;
unsigned char sha1[20];
struct packed_git *p;
};
struct ref {
struct ref *next;
unsigned char old_sha1[20];
unsigned char new_sha1[20];
unsigned int force:1,
merge:1,
nonfastforward:1,
deletion:1;
enum {
REF_STATUS_NONE = 0,
REF_STATUS_OK,
REF_STATUS_REJECT_NONFASTFORWARD,
REF_STATUS_REJECT_NODELETE,
REF_STATUS_UPTODATE,
REF_STATUS_REMOTE_REJECT,
REF_STATUS_EXPECTING_REPORT,
} status;
char *remote_status;
struct ref *peer_ref; /* when renaming */
char name[FLEX_ARRAY]; /* more */
};
#define REF_NORMAL (1u << 0)
#define REF_HEADS (1u << 1)
#define REF_TAGS (1u << 2)
extern struct ref *find_ref_by_name(struct ref *list, const char *name);
#define CONNECT_VERBOSE (1u << 0)
extern struct child_process *git_connect(int fd[2], const char *url, const char *prog, int flags);
extern int finish_connect(struct child_process *conn);
extern int path_match(const char *path, int nr, char **match);
extern int get_ack(int fd, unsigned char *result_sha1);
extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match, unsigned int flags);
extern int server_supports(const char *feature);
extern struct packed_git *parse_pack_index(unsigned char *sha1);
extern struct packed_git *parse_pack_index_file(const unsigned char *sha1,
const char *idx_path);
extern void prepare_packed_git(void);
extern void reprepare_packed_git(void);
extern void install_packed_git(struct packed_git *pack);
extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
struct packed_git *packs);
extern void pack_report(void);
extern int open_pack_index(struct packed_git *);
extern unsigned char* use_pack(struct packed_git *, struct pack_window **, off_t, unsigned int *);
extern void close_pack_windows(struct packed_git *);
extern void unuse_pack(struct pack_window **);
extern struct packed_git *add_packed_git(const char *, int, int);
extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t);
extern off_t find_pack_entry_one(const unsigned char *, struct packed_git *);
extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
extern unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
extern const char *packed_object_info_detail(struct packed_git *, off_t, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
extern int matches_pack_name(struct packed_git *p, const char *name);
/* Dumb servers support */
extern int update_server_info(int);
typedef int (*config_fn_t)(const char *, const char *);
extern int git_default_config(const char *, const char *);
extern int git_config_from_file(config_fn_t fn, const char *);
extern int git_config(config_fn_t fn);
extern int git_parse_long(const char *, long *);
extern int git_parse_ulong(const char *, unsigned long *);
extern int git_config_int(const char *, const char *);
extern unsigned long git_config_ulong(const char *, const char *);
extern int git_config_bool(const char *, const char *);
extern int git_config_set(const char *, const char *);
extern int git_config_set_multivar(const char *, const char *, const char *, int);
extern int git_config_rename_section(const char *, const char *);
extern const char *git_etc_gitconfig(void);
extern int check_repository_format_version(const char *var, const char *value);
#define MAX_GITNAME (1000)
extern char git_default_email[MAX_GITNAME];
extern char git_default_name[MAX_GITNAME];
extern const char *git_commit_encoding;
extern const char *git_log_output_encoding;
/* IO helper functions */
extern void maybe_flush_or_die(FILE *, const char *);
extern int copy_fd(int ifd, int ofd);
extern int read_in_full(int fd, void *buf, size_t count);
extern int write_in_full(int fd, const void *buf, size_t count);
extern void write_or_die(int fd, const void *buf, size_t count);
extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg);
/* pager.c */
extern void setup_pager(void);
extern char *pager_program;
extern int pager_in_use(void);
extern int pager_use_color;
extern char *editor_program;
extern char *excludes_file;
/* base85 */
int decode_85(char *dst, const char *line, int linelen);
void encode_85(char *buf, const unsigned char *data, int bytes);
/* alloc.c */
extern void *alloc_blob_node(void);
extern void *alloc_tree_node(void);
extern void *alloc_commit_node(void);
extern void *alloc_tag_node(void);
extern void *alloc_object_node(void);
extern void alloc_report(void);
/* trace.c */
extern void trace_printf(const char *format, ...);
extern void trace_argv_printf(const char **argv, const char *format, ...);
/* convert.c */
/* returns 1 if *dst was used */
extern int convert_to_git(const char *path, const char *src, size_t len, struct strbuf *dst);
extern int convert_to_working_tree(const char *path, const char *src, size_t len, struct strbuf *dst);
/* add */
void add_files_to_cache(int verbose, const char *prefix, const char **pathspec);
/* diff.c */
extern int diff_auto_refresh_index;
/* match-trees.c */
void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
/*
* whitespace rules.
* used by both diff and apply
*/
#define WS_TRAILING_SPACE 01
#define WS_SPACE_BEFORE_TAB 02
#define WS_INDENT_WITH_NON_TAB 04
#define WS_DEFAULT_RULE (WS_TRAILING_SPACE|WS_SPACE_BEFORE_TAB)
extern unsigned whitespace_rule_cfg;
extern unsigned whitespace_rule(const char *);
extern unsigned parse_whitespace_rule(const char *);
extern unsigned check_and_emit_line(const char *line, int len, unsigned ws_rule,
FILE *stream, const char *set,
const char *reset, const char *ws);
extern char *whitespace_error_string(unsigned ws);
/* ls-files */
int pathspec_match(const char **spec, char *matched, const char *filename, int skiplen);
int report_path_error(const char *ps_matched, const char **pathspec, int prefix_offset);
void overlay_tree_on_cache(const char *tree_name, const char *prefix);
#endif /* CACHE_H */