SSDB's network protocol is extremly ass kicking SIMPLE!
Packet := Block+ '\n'
Block := Size '\n' Data '\n'
Size := literal_integer
Data := size_bytes_of_data
Request := Cmd Blocks*
Cmd := Block
Commands are: get, set, del, ...
Response := Status Block*
Status := Block
Status codes are: ok, not_found, error, fail, client_error
Connect to a SSDB server with telnet or nc, then type in these codes(with an empty line at the end):
3
get
3
key
You will get response like this:
2
ok
3
val
#include <stdlib.h>
#include <string.h>
int len = buffer->size();
char *ptr = buffer->data();
while(len > 0){
char *data = (char *)memchr(ptr, '\n', len);
if(data == NULL){
break;
}
data += 1;
int num = data - ptr;
if(num == 1 || (num == 2 && ptr[0] == '\r')){
// Packet received.
return OK;
}
// Size received
int size = (int)strtol(ptr, NULL, 10);
len -= num + size;
ptr += num + size;
if(len >= 1 && ptr[0] = '\n'){
len -= 1;
ptr += 1;
}else if(len >= 2 && ptr[0] == '\r' && ptr[1] == '\n'){
len -= 2;
ptr += 2;
}else{
break;
}
// Data received
}
Advice to SDK developers: Data
may contains any character, including \r, \n, \0...
, so you MUST NOT expecting there is no such thing in Data
.