git-commit-vandalism/cache.h
Junio C Hamano 1084b845d9 Fix infinite loop when deleting multiple packed refs.
It was stupid to link the same element twice to lock_file_list
and end up in a loop, so we certainly need a fix.

But it is not like we are taking a lock on multiple files in
this case.  It is just that we leave the linked element on the
list even after commit_lock_file() successfully removes the
cruft.

We cannot remove the list element in commit_lock_file(); if we
are interrupted in the middle of list manipulation, the call to
remove_lock_file_on_signal() will happen with a broken list
structure pointed by lock_file_list, which would cause the cruft
to remain, so not removing the list element is the right thing
to do.  Instead we should be reusing the element already on the
list.

There is already a code for that in lock_file() function in
lockfile.c.  The code checks lk->next and the element is linked
only when it is not already on the list -- which is incorrect
for the last element on the list (which has NULL in its next
field), but if you read the check as "is this element already on
the list?" it actually makes sense.  We do not want to link it
on the list again, nor we would want to set up signal/atexit
over and over.

Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-01-03 01:22:35 -08:00

446 lines
15 KiB
C

#ifndef CACHE_H
#define CACHE_H
#include "git-compat-util.h"
#include SHA1_HEADER
#include <zlib.h>
#if 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
/*
* 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);
return htonl(S_IFREG | ce_permissions(mode));
}
#define canon_mode(mode) \
(S_ISREG(mode) ? (S_IFREG | ce_permissions(mode)) : \
S_ISLNK(mode) ? S_IFLNK : S_IFDIR)
#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;
extern struct cache_tree *active_cache_tree;
extern int cache_errno;
#define GIT_DIR_ENVIRONMENT "GIT_DIR"
#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
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);
#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
extern const char **get_pathspec(const char *prefix, const char **pathspec);
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)
/* Initialize and use the cache information */
extern int read_cache(void);
extern int read_cache_from(const char *path);
extern int write_cache(int newfd, struct cache_entry **cache, int entries);
extern int discard_cache(void);
extern int verify_path(const char *path);
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 struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
extern int remove_cache_entry_at(int pos);
extern int remove_file_from_cache(const char *path);
extern int add_file_to_index(const char *path, int verbose);
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, int);
extern int ce_modified(struct cache_entry *ce, struct stat *st, 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, const char *type);
extern int read_pipe(int fd, char** return_buf, unsigned long* return_size);
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_cache(unsigned int flags);
struct lock_file {
struct lock_file *next;
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 void rollback_lock_file(struct lock_file *);
extern int delete_ref(const char *, unsigned char *sha1);
/* Environment bits from configuration mechanism */
extern int use_legacy_headers;
extern int trust_executable_bit;
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;
#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);
/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
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 hash_sha1_file(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 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 void *map_sha1_file(const unsigned char *sha1, unsigned long *);
extern int legacy_loose_object(unsigned char *);
extern int has_pack_file(const unsigned char *sha1);
extern int has_pack_index(const unsigned char *sha1);
enum object_type {
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_BAD,
};
extern signed char hexval_table[256];
static inline unsigned int hexval(unsigned int 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_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 create_symref(const char *ref, const char *refs_heads_master);
extern int validate_symref(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);
const char *show_date(unsigned long time, int timezone, int relative);
const char *show_rfc2822_date(unsigned long time, int timezone);
int parse_date(const char *date, char *buf, int bufsize);
void datestamp(char *buf, int bufsize);
unsigned long approxidate(const char *);
extern int setup_ident(void);
extern const char *git_author_info(int);
extern const char *git_committer_info(int);
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, char *topath);
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);
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;
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 {
unsigned int 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 char force;
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 pid_t git_connect(int fd[2], char *url, const char *prog);
extern int finish_connect(pid_t pid);
extern int path_match(const char *path, int nr, char **match);
extern int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
int nr_refspec, char **refspec, int all);
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,
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 int use_packed_git(struct packed_git *);
extern void unuse_packed_git(struct packed_git *);
extern struct packed_git *add_packed_git(char *, int, 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 unsigned long find_pack_entry_one(const unsigned char *, struct packed_git *);
extern void *unpack_entry_gently(struct packed_git *, unsigned long, char *, unsigned long *);
extern unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
extern void packed_object_info_detail(struct packed_git *, unsigned long, char *, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
/* 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_config_int(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 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];
#define MAX_ENCODING_LENGTH 64
extern char git_commit_encoding[MAX_ENCODING_LENGTH];
extern int copy_fd(int ifd, int ofd);
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);
/* pager.c */
extern void setup_pager(void);
extern int pager_in_use;
extern int pager_use_color;
/* base85 */
int decode_85(char *dst, char *line, int linelen);
void encode_85(char *buf, unsigned char *data, int bytes);
/* alloc.c */
struct blob;
struct tree;
struct commit;
struct tag;
extern struct blob *alloc_blob_node(void);
extern struct tree *alloc_tree_node(void);
extern struct commit *alloc_commit_node(void);
extern struct tag *alloc_tag_node(void);
extern void alloc_report(void);
/* trace.c */
extern int nfvasprintf(char **str, const char *fmt, va_list va);
extern void trace_printf(const char *format, ...);
extern void trace_argv_printf(const char **argv, int count, const char *format, ...);
#endif /* CACHE_H */