forked from agorise/c-ipfs
c8fdb084e4
The files are now stored in the same format. Now it is necessary to reverse engineer the directory structure
73 lines
1.7 KiB
C
73 lines
1.7 KiB
C
#include <stdio.h>
|
|
#include <string.h>
|
|
|
|
#include "ipfs/cid/cid.h"
|
|
#include "ipfs/merkledag/merkledag.h"
|
|
#include "ipfs/merkledag/node.h"
|
|
#include "ipfs/repo/fsrepo/fs_repo.h"
|
|
/**
|
|
* pull objects from ipfs
|
|
*/
|
|
|
|
/**
|
|
* get a file by its hash, and write the data to a file
|
|
* @param hash the base58 multihash of the cid
|
|
* @param file_name the file name to write to
|
|
* @returns true(1) on success
|
|
*/
|
|
int ipfs_exporter_to_file(const unsigned char* hash, const char* file_name, const struct FSRepo* fs_repo) {
|
|
// convert hash to cid
|
|
struct Cid* cid = NULL;
|
|
if ( ipfs_cid_decode_hash_from_base58(hash, strlen((char*)hash), &cid) == 0) {
|
|
return 0;
|
|
}
|
|
|
|
// find block
|
|
struct Node* read_node = NULL;
|
|
if (ipfs_merkledag_get(cid->hash, cid->hash_length, &read_node, fs_repo) == 0) {
|
|
ipfs_cid_free(cid);
|
|
return 0;
|
|
}
|
|
|
|
// no longer need the cid
|
|
ipfs_cid_free(cid);
|
|
|
|
// process blocks
|
|
FILE* file = fopen(file_name, "wb");
|
|
if (file == NULL) {
|
|
ipfs_node_free(read_node);
|
|
return 0;
|
|
}
|
|
size_t bytes_written = fwrite(read_node->data, 1, read_node->data_size, file);
|
|
if (bytes_written != read_node->data_size) {
|
|
fclose(file);
|
|
ipfs_node_free(read_node);
|
|
return 0;
|
|
}
|
|
struct NodeLink* link = read_node->head_link;
|
|
struct Node* link_node = NULL;
|
|
while (link != NULL) {
|
|
if ( ipfs_merkledag_get(link->hash, link->hash_size, &link_node, fs_repo) == 0) {
|
|
fclose(file);
|
|
ipfs_node_free(read_node);
|
|
return 0;
|
|
}
|
|
bytes_written = fwrite(link_node->data, 1, link_node->data_size, file);
|
|
if (bytes_written != link_node->data_size) {
|
|
ipfs_node_free(link_node);
|
|
fclose(file);
|
|
ipfs_node_free(read_node);
|
|
return 0;
|
|
}
|
|
ipfs_node_free(link_node);
|
|
link = link->next;
|
|
}
|
|
|
|
fclose(file);
|
|
|
|
if (read_node != NULL)
|
|
ipfs_node_free(read_node);
|
|
|
|
return 1;
|
|
}
|