c-ipfs/importer/exporter.c
2016-12-23 17:21:04 -05:00

205 lines
5.2 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;
}
/**
* 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_console(const unsigned char* hash, 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
struct NodeLink* link = read_node->head_link;
printf("{Links:[");
while (link != NULL) {
unsigned char b58[100];
ipfs_cid_hash_to_base58(link->hash, link->hash_size, b58, 100);
printf("{\"Name\":\"%s\",\"Hash\":\"%s\",\"Size\":%lu}", (link->name != NULL ? link->name : ""), (char*)b58, link->t_size);
link = link->next;
}
printf("],\"Data\":\"");
for(size_t i = 0LU; i < read_node->data_size; i++) {
printf("%02x", read_node->data[i]);
}
printf("\"}\n");
if (read_node != NULL)
ipfs_node_free(read_node);
return 1;
}
/***
* Called from the command line with ipfs object get [hash]. Retrieves the object pointed to by hash, and displays its block data (links and data elements)
* @param argc number of arguments
* @param argv arguments
* @returns true(1) on success
*/
int ipfs_exporter_object_get(int argc, char** argv) {
struct FSRepo* fs_repo = NULL;
// open the repo
int retVal = ipfs_repo_fsrepo_new(NULL, NULL, &fs_repo);
if (retVal == 0) {
return 0;
}
retVal = ipfs_repo_fsrepo_open(fs_repo);
if (retVal == 0) {
return 0;
}
// find hash
retVal = ipfs_exporter_to_console((unsigned char*)argv[3], fs_repo);
return retVal;
}
int ipfs_exporter_cat_node(struct Node* node, const struct FSRepo* fs_repo) {
// process this node, then move on to the links
// build the unixfs
struct UnixFS* unix_fs;
ipfs_unixfs_protobuf_decode(node->data, node->data_size, &unix_fs);
for(size_t i = 0LU; i < unix_fs->bytes_size; i++) {
printf("%c", unix_fs->bytes[i]);
}
// process links
struct NodeLink* current = node->head_link;
while (current != NULL) {
// find the node
struct Node* child_node = NULL;
if (ipfs_merkledag_get(current->hash, current->hash_size, &child_node, fs_repo) == 0) {
return 0;
}
ipfs_exporter_cat_node(child_node, fs_repo);
ipfs_node_free(child_node);
current = current->next;
}
return 1;
}
/***
* Called from the command line with ipfs cat [hash]. Retrieves the object pointed to by hash, and displays its block data (links and data elements)
* @param argc number of arguments
* @param argv arguments
* @returns true(1) on success
*/
int ipfs_exporter_object_cat(int argc, char** argv) {
struct FSRepo* fs_repo = NULL;
// open the repo
int retVal = ipfs_repo_fsrepo_new(NULL, NULL, &fs_repo);
if (retVal == 0) {
return 0;
}
retVal = ipfs_repo_fsrepo_open(fs_repo);
if (retVal == 0) {
return 0;
}
// find hash
// convert hash to cid
struct Cid* cid = NULL;
if ( ipfs_cid_decode_hash_from_base58((unsigned char*)argv[2], strlen(argv[2]), &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);
ipfs_exporter_cat_node(read_node, fs_repo);
ipfs_node_free(read_node);
return retVal;
}