bool LocalMemoryGridFile::initLocalBuffers(GridFile& gridFile) {
if (!setSize(gridFile.getContentLength())) {
return false;
}
//TODO: Check for size compared to the content length that was specified for consistency
off_t offset = 0;
int chunkCount = gridFile.getNumChunks();
for (int i = 0; i < chunkCount; ++i) {
//TODO: Error checking or getChunk and related handling
GridFSChunk chunk = gridFile.getChunk(i);
int chunkLen = 0;
const char* data = chunk.data(chunkLen);
if (!data) {
error() << "Failed to get data from expected chunk {file: " << _filename
<< ", chunkOffset: " << i << ", totalChunks: " << chunkCount
<< "}, will stop in-between and return error." << endl;
return false;
}
_write(data, chunkLen, offset);
offset += chunkLen;
}
return true;
}
int gridfs_read(const char *path, char *buf, size_t size, off_t offset,
struct fuse_file_info *fi)
{
path = fuse_to_mongo_path(path);
size_t len = 0;
map<string,LocalGridFile*>::const_iterator file_iter;
file_iter = open_files.find(path);
if(file_iter != open_files.end()) {
LocalGridFile *lgf = file_iter->second;
return lgf->read(buf, size, offset);
}
ScopedDbConnection sdc(*gridfs_options.conn_string);
bool digest = true;
string err = "";
sdc.conn().DBClientWithCommands::auth(gridfs_options.db, gridfs_options.username, gridfs_options.password, err, digest);
fprintf(stderr, "DEBUG: %s\n", err.c_str());
GridFS gf(sdc.conn(), gridfs_options.db);
GridFile file = gf.findFile(path);
if(!file.exists()) {
sdc.done();
return -EBADF;
}
int chunk_size = file.getChunkSize();
int chunk_num = offset / chunk_size;
while(len < size && chunk_num < file.getNumChunks()) {
GridFSChunk chunk = file.getChunk(chunk_num);
int to_read;
int cl = chunk.len();
const char *d = chunk.data(cl);
if(len) {
to_read = min((long unsigned)cl, (long unsigned)(size - len));
memcpy(buf + len, d, to_read);
} else {
to_read = min((long unsigned)(cl - (offset % chunk_size)), (long unsigned)(size - len));
memcpy(buf + len, d + (offset % chunk_size), to_read);
}
len += to_read;
chunk_num++;
}
sdc.done();
return len;
}
gridfs_offset GridFile::write( ostream & out ) {
_exists();
const int num = getNumChunks();
for ( int i=0; i<num; i++ ) {
GridFSChunk c = getChunk( i );
int len;
const char * data = c.data( len );
out.write( data , len );
}
return getContentLength();
}
int gridfs_read(const char *path, char *buf, size_t size, off_t offset,
struct fuse_file_info *fi)
{
path = fuse_to_mongo_path(path);
size_t len = 0;
map<string,LocalGridFile*>::const_iterator file_iter;
file_iter = open_files.find(path);
if(file_iter != open_files.end()) {
LocalGridFile *lgf = file_iter->second;
return lgf->read(buf, size, offset);
}
ScopedDbConnection sdc(*gridfs_options.conn_string);
ScopedDbConnection_init(sdc);
GridFS gf(sdc.conn(), gridfs_options.db, gridfs_options.prefix);
GridFile file = gf.findFile(path);
if(!file.exists()) {
sdc.done();
return -EBADF;
}
int chunk_size = file.getChunkSize();
int chunk_num = offset / chunk_size;
while(len < size && chunk_num < file.getNumChunks()) {
GridFSChunk chunk = file.getChunk(chunk_num);
int to_read;
int cl = chunk.len();
const char *d = chunk.data(cl);
if(len) {
to_read = min((long unsigned)cl, (long unsigned)(size - len));
memcpy(buf + len, d, to_read);
} else {
to_read = min((long unsigned)(cl - (offset % chunk_size)), (long unsigned)(size - len));
memcpy(buf + len, d + (offset % chunk_size), to_read);
}
len += to_read;
chunk_num++;
}
sdc.done();
return len;
}
