GNUnet  0.11.x
gnunet-service-messenger_list_messages.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2020--2021 GNUnet e.V.
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your option) any later version.
9 
10  GNUnet is distributed in the hope that it will be useful, but
11  WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19  */
27 
28 void
30 {
31  GNUNET_assert(messages);
32 
33  messages->head = NULL;
34  messages->tail = NULL;
35 }
36 
37 void
39 {
40  GNUNET_assert(messages);
41 
42  while (messages->head)
43  {
44  struct GNUNET_MESSENGER_ListMessage *element = messages->head;
45 
46  GNUNET_CONTAINER_DLL_remove(messages->head, messages->tail, element);
47  GNUNET_free(element);
48  }
49 
50  messages->head = NULL;
51  messages->tail = NULL;
52 }
53 
54 void
56 {
57  GNUNET_assert((messages) && (hash));
58 
60 
61  GNUNET_memcpy(&(element->hash), hash, sizeof(struct GNUNET_HashCode));
62 
63  GNUNET_CONTAINER_DLL_insert_tail(messages->head, messages->tail, element);
64 }
65 
66 void
68 {
69  GNUNET_assert((messages) && (origin));
70 
71  struct GNUNET_MESSENGER_ListMessage *element;
72 
73  for (element = origin->head; element; element = element->next)
74  add_to_list_messages (messages, &(element->hash));
75 }
76 
77 void
79 {
80  GNUNET_assert((messages) && (hash));
81 
82  struct GNUNET_MESSENGER_ListMessage *element;
83 
84  for (element = messages->head; element; element = element->next)
85  if (0 == GNUNET_CRYPTO_hash_cmp (&(element->hash), hash))
86  {
87  GNUNET_CONTAINER_DLL_remove(messages->head, messages->tail, element);
88  GNUNET_free(element);
89  break;
90  }
91 }
92 
93 void
94 load_list_messages (struct GNUNET_MESSENGER_ListMessages *messages, const char *path)
95 {
96  GNUNET_assert((messages) && (path));
97 
98  if (GNUNET_YES != GNUNET_DISK_file_test (path))
99  return;
100 
102 
104  path, GNUNET_DISK_OPEN_READ, permission
105  );
106 
107  if (!handle)
108  return;
109 
111 
112  struct GNUNET_HashCode hash;
113  ssize_t len;
114 
115  do {
116  len = GNUNET_DISK_file_read(handle, &hash, sizeof(hash));
117 
118  if (len != sizeof(hash))
119  break;
120 
121  add_to_list_messages(messages, &hash);
122  } while (len == sizeof(hash));
123 
124  GNUNET_DISK_file_close(handle);
125 }
126 
127 void
128 save_list_messages (const struct GNUNET_MESSENGER_ListMessages *messages, const char *path)
129 {
130  GNUNET_assert((messages) && (path));
131 
133 
136  );
137 
138  if (!handle)
139  return;
140 
142 
143  struct GNUNET_MESSENGER_ListMessage *element;
144 
145  for (element = messages->head; element; element = element->next)
146  GNUNET_DISK_file_write(handle, &(element->hash), sizeof(element->hash));
147 
148  GNUNET_DISK_file_sync(handle);
149  GNUNET_DISK_file_close(handle);
150 }
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
Open the file for reading.
Create file if it doesn&#39;t exist.
struct GNUNET_MESSENGER_ListMessage * next
struct GNUNET_MESSENGER_ListMessage * head
ssize_t GNUNET_DISK_file_read(const struct GNUNET_DISK_FileHandle *h, void *result, size_t len)
Read the contents of a binary file into a buffer.
Definition: disk.c:622
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
enum GNUNET_GenericReturnValue GNUNET_DISK_file_close(struct GNUNET_DISK_FileHandle *h)
Close an open file.
Definition: disk.c:1305
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
#define GNUNET_new(type)
Allocate a struct or union of the given type.
off_t GNUNET_DISK_file_seek(const struct GNUNET_DISK_FileHandle *h, off_t offset, enum GNUNET_DISK_Seek whence)
Move the read/write pointer in a file.
Definition: disk.c:206
void save_list_messages(const struct GNUNET_MESSENGER_ListMessages *messages, const char *path)
Saves the list of message hashes to a file under a given path.
void init_list_messages(struct GNUNET_MESSENGER_ListMessages *messages)
Initializes list of message hashes as empty list.
ssize_t GNUNET_DISK_file_write(const struct GNUNET_DISK_FileHandle *h, const void *buffer, size_t n)
Write a buffer to a file.
Definition: disk.c:686
void add_to_list_messages(struct GNUNET_MESSENGER_ListMessages *messages, const struct GNUNET_HashCode *hash)
Adds a specific hash from a message to the end of the list.
void load_list_messages(struct GNUNET_MESSENGER_ListMessages *messages, const char *path)
Loads the list of message hashes from a file under a given path.
static struct GNUNET_DNS_Handle * handle
Handle to transport service.
GNUNET_DISK_AccessPermissions
File access permissions, UNIX-style.
A 512-bit hashcode.
Open the file for writing.
void remove_from_list_messages(struct GNUNET_MESSENGER_ListMessages *messages, const struct GNUNET_HashCode *hash)
Removes the first entry with a matching hash from the list.
#define GNUNET_CONTAINER_DLL_insert_tail(head, tail, element)
Insert an element at the tail of a DLL.
struct GNUNET_MESSENGER_ListMessage * tail
void clear_list_messages(struct GNUNET_MESSENGER_ListMessages *messages)
Clears the list of message hashes.
Seek an absolute position (from the start of the file).
int GNUNET_CRYPTO_hash_cmp(const struct GNUNET_HashCode *h1, const struct GNUNET_HashCode *h2)
Compare function for HashCodes, producing a total ordering of all hashcodes.
Definition: crypto_hash.c:201
enum GNUNET_GenericReturnValue GNUNET_DISK_file_sync(const struct GNUNET_DISK_FileHandle *h)
Write file changes to disk.
Definition: disk.c:1424
void copy_list_messages(struct GNUNET_MESSENGER_ListMessages *messages, const struct GNUNET_MESSENGER_ListMessages *origin)
Copies all message hashes from an origin to another list.
struct GNUNET_DISK_FileHandle * GNUNET_DISK_file_open(const char *fn, enum GNUNET_DISK_OpenFlags flags, enum GNUNET_DISK_AccessPermissions perm)
Open a file.
Definition: disk.c:1234
Handle used to access files (and pipes).
enum GNUNET_GenericReturnValue GNUNET_DISK_file_test(const char *fil)
Check that fil corresponds to a filename (of a file that exists and that is not a directory)...
Definition: disk.c:482
#define GNUNET_free(ptr)
Wrapper around free.
uint16_t len
length of data (which is always a uint32_t, but presumably this can be used to specify that fewer byt...