src/odb.h

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7 #ifndef INCLUDE_odb_h__
   8 #define INCLUDE_odb_h__
   9
  10 #include "git2/odb.h"
  11 #include "git2/oid.h"
  12 #include "git2/types.h"
  13
  14 #include "vector.h"
  15 #include "cache.h"
  16 #include "posix.h"
  17 #include "filter.h"
  18
  19 #define GIT_OBJECTS_DIR "objects/"
  20 #define GIT_OBJECT_DIR_MODE 0777
  21 #define GIT_OBJECT_FILE_MODE 0444
  22
  23 extern bool git_odb__strict_hash_verification;
  24
  25 /* DO NOT EXPORT */
  26 typedef struct {
  27         void *data;                     /**< Raw, decompressed object data. */
  28         size_t len;                     /**< Total number of bytes in data. */
  29         git_otype type;         /**< Type of this object. */
  30 } git_rawobj;
  31
  32 /* EXPORT */
  33 struct git_odb_object {
  34         git_cached_obj cached;
  35         void *buffer;
  36 };
  37
  38 /* EXPORT */
  39 struct git_odb {
  40         git_refcount rc;
  41         git_vector backends;
  42         git_cache own_cache;
  43         unsigned int do_fsync :1;
  44 };
  45
  46 typedef enum {
  47         GIT_ODB_CAP_FROM_OWNER = -1,
  48 } git_odb_cap_t;
  49
  50 /*
  51  * Set the capabilities for the object database.
  52  */
  53 int git_odb__set_caps(git_odb *odb, int caps);
  54
  55 /*
  56  * Add the default loose and packed backends for a database.
  57  */
  58 int git_odb__add_default_backends(
  59         git_odb *db, const char *objects_dir,
  60         bool as_alternates, int alternate_depth);
  61
  62 /*
  63  * Hash a git_rawobj internally.
  64  * The `git_rawobj` is supposed to be previously initialized
  65  */
  66 int git_odb__hashobj(git_oid *id, git_rawobj *obj);
  67
  68 /*
  69  * Format the object header such as it would appear in the on-disk object
  70  */
  71 int git_odb__format_object_header(char *hdr, size_t n, git_off_t obj_len, git_otype obj_type);
  72 /*
  73  * Hash an open file descriptor.
  74  * This is a performance call when the contents of a fd need to be hashed,
  75  * but the fd is already open and we have the size of the contents.
  76  *
  77  * Saves us some `stat` calls.
  78  *
  79  * The fd is never closed, not even on error. It must be opened and closed
  80  * by the caller
  81  */
  82 int git_odb__hashfd(git_oid *out, git_file fd, size_t size, git_otype type);
  83
  84 /*
  85  * Hash an open file descriptor applying an array of filters
  86  * Acts just like git_odb__hashfd with the addition of filters...
  87  */
  88 int git_odb__hashfd_filtered(
  89         git_oid *out, git_file fd, size_t len, git_otype type, git_filter_list *fl);
  90
  91 /*
  92  * Hash a `path`, assuming it could be a POSIX symlink: if the path is a
  93  * symlink, then the raw contents of the symlink will be hashed. Otherwise,
  94  * this will fallback to `git_odb__hashfd`.
  95  *
  96  * The hash type for this call is always `GIT_OBJ_BLOB` because symlinks may
  97  * only point to blobs.
  98  */
  99 int git_odb__hashlink(git_oid *out, const char *path);
 100
 101 /**
 102  * Generate a GIT_EMISMATCH error for the ODB.
 103  */
 104 int git_odb__error_mismatch(
 105         const git_oid *expected, const git_oid *actual);
 106
 107 /*
 108  * Generate a GIT_ENOTFOUND error for the ODB.
 109  */
 110 int git_odb__error_notfound(
 111         const char *message, const git_oid *oid, size_t oid_len);
 112
 113 /*
 114  * Generate a GIT_EAMBIGUOUS error for the ODB.
 115  */
 116 int git_odb__error_ambiguous(const char *message);
 117
 118 /*
 119  * Attempt to read object header or just return whole object if it could
 120  * not be read.
 121  */
 122 int git_odb__read_header_or_object(
 123         git_odb_object **out, size_t *len_p, git_otype *type_p,
 124         git_odb *db, const git_oid *id);
 125
 126 /* freshen an entry in the object database */
 127 int git_odb__freshen(git_odb *db, const git_oid *id);
 128
 129 /* fully free the object; internal method, DO NOT EXPORT */
 130 void git_odb_object__free(void *object);
 131
 132 #endif