summaryrefslogtreecommitdiff
path: root/src/filesdb.h
blob: 912dea12dd038398a88d2014cf3d353f2147216f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/*
 * dpkg - main program for package management
 * filesdb.h - management of database of files installed on system
 *
 * Copyright (C) 1995 Ian Jackson <ian@chiark.greenend.org.uk>
 *
 * This is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2,
 * or (at your option) any later version.
 *
 * This is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with dpkg; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef FILESDB_H
#define FILESDB_H

/*
 * Data structure here is as follows:
 * 
 * For each package we have a `struct fileinlist *', the head of
 * a list of files in that package.  They are in `forwards' order.
 * Each entry has a pointer to the `struct filenamenode'.
 *
 * The struct filenamenodes are in a hash table, indexed by name.
 * (This hash table is not visible to callers.)
 *
 * Each filenamenode has a (possibly empty) list of `struct
 * filepackage', giving a list of the packages listing that
 * filename.
 *
 * When we read files contained info about a particular package
 * we set the `files' member of the clientdata struct to the
 * appropriate thing.  When not yet set the files pointer is
 * made to point to `fileslist_uninited' (this is available only
 * internally, withing filesdb.c - the published interface is
 * ensure_*_available).
 */

struct pkginfo;

/* flags to findnamenode() */

enum fnnflags {
    fnn_nocopy=                 000001, /* do not need to copy filename */
};

struct filenamenode {
  struct filenamenode *next;
  const char *name;
  struct filepackages *packages;
  struct diversion *divert;
  struct filestatoverride *statoverride;
  /* Fields from here on are used by archives.c &c, and cleared by
   * filesdbinit.
   */
  enum {
    fnnf_new_conff=           000001, /* in the newconffiles list */
    fnnf_new_inarchive=       000002, /* in the new filesystem archive */
    fnnf_old_conff=           000004, /* in the old package's conffiles list */
    fnnf_obs_conff=           000100, /* obsolete conffile */
    fnnf_elide_other_lists=   000010, /* must remove from other packages' lists */
    fnnf_no_atomic_overwrite= 000020, /* >=1 instance is a dir, cannot rename over */
    fnnf_placed_on_disk=      000040, /* new file has been placed on the disk */
  } flags; /* Set to zero when a new node is created. */
  const char *oldhash; /* valid iff this namenode is in the newconffiles list */
  struct stat *filestat;
};
 
struct fileinlist {
  struct fileinlist *next;
  struct filenamenode *namenode;
};

struct filestatoverride {
  /* We allow the administrator to override the owner, group and mode of
   * a file. If such an override is present we use that instead of the
   * stat information stored in the archive.
   *
   * This functionality used to be in the suidmanager package.
   */
  uid_t uid;
  gid_t gid;
  mode_t mode;
};

struct diversion {
  /* When we deal with an `overridden' file, every package except
   * the overriding one is considered to contain the other file
   * instead.  Both files have entries in the filesdb database, and
   * they refer to each other via these diversion structures.
   *
   * The contested filename's filenamenode has an diversion entry
   * with useinstead set to point to the redirected filename's
   * filenamenode; the redirected filenamenode has camefrom set to the
   * contested filenamenode.  Both sides' diversion entries will
   * have pkg set to the package (if any) which is allowed to use the
   * contended filename.
   *
   * Packages that contain either version of the file will all
   * refer to the contested filenamenode in their per-file package lists
   * (both in core and on disk).  References are redirected to the other
   * filenamenode's filename where appropriate.
   */
  struct filenamenode *useinstead;
  struct filenamenode *camefrom;
  struct pkginfo *pkg;
  struct diversion *next;
  /* The `contested' halves are in this list for easy cleanup. */
};

#define PERFILEPACKAGESLUMP 10

struct filepackages {
  struct filepackages *more;
  struct pkginfo *pkgs[PERFILEPACKAGESLUMP];
  /* pkgs is a null-pointer-terminated list; anything after the first null
   * is garbage
   */
};

struct fileiterator;
struct fileiterator *iterfilestart(void);
struct filenamenode *iterfilenext(struct fileiterator *i);
void iterfileend(struct fileiterator *i);

void ensure_diversions(void);
void ensure_statoverrides(void);

void ensure_packagefiles_available(struct pkginfo *pkg);
void ensure_allinstfiles_available(void);
void ensure_allinstfiles_available_quiet(void);
void note_must_reread_files_inpackage(struct pkginfo *pkg);
struct filenamenode *findnamenode(const char *filename, enum fnnflags flags);
void write_filelist_except(struct pkginfo *pkg, struct fileinlist *list, int leaveout);

struct reversefilelistiter { struct fileinlist *todo; };

void reversefilelist_init(struct reversefilelistiter *iterptr, struct fileinlist *files);
struct filenamenode *reversefilelist_next(struct reversefilelistiter *iterptr);
void reversefilelist_abort(struct reversefilelistiter *iterptr);

#endif /* FILESDB_H */