Hello @jeremyhahn, first of all, thank you for the project. Good Stuff.

One of our developers did a quick fork and started playing with it. We added socketio support. We are happy to share it back.

Nevertheless, I was thinking about using this in an iOS app and, sadly, the LGPL license will not allow it.

Are you open to do an MIT/BSD license on this?

The frame headers are wrong for frames with payload length over 65535. The below line in cwebsocket_write_data adds 10 additional bytes to header length when it should be only 8.

uint32_t header_length = 6 + (payload_len > 125 ? 2 : 0) + (payload_len > 0xffff ? 8 : 0);

Changing this to the below solves it.

uint32_t header_length = 6 + (payload_len > 125 ? 2 : 0) + (payload_len > 0xffff ? 6 : 0);

In common.h

#define htonl64(p) {\
	(char)(((p & ((uint64_t)0xff <<  0)) >>  0) & 0xff), (char)(((p & ((uint64_t)0xff <<  8)) >>  8) & 0xff), \
	(char)(((p & ((uint64_t)0xff << 16)) >> 16) & 0xff), (char)(((p & ((uint64_t)0xff << 24)) >> 24) & 0xff), \
	(char)(((p & ((uint64_t)0xff << 32)) >> 32) & 0xff), (char)(((p & ((uint64_t)0xff << 40)) >> 40) & 0xff), \
(char)(((p & ((uint64_t)0xff << 48)) >> 48) & 0xff), (char)(((p & ((uint64_t)0xff << 56)) >> 56) & 0xff) }

needs to be changed to

#define htonl64(p) {\
    (char)(((p & ((uint64_t)0xff << 56)) >> 56) & 0xff), (char)(((p & ((uint64_t)0xff << 48)) >> 48) & 0xff), \
    (char)(((p & ((uint64_t)0xff << 40)) >> 40) & 0xff), (char)(((p & ((uint64_t)0xff << 32)) >> 32) & 0xff), \
    (char)(((p & ((uint64_t)0xff << 24)) >> 24) & 0xff), (char)(((p & ((uint64_t)0xff << 16)) >> 16) & 0xff), \
    (char)(((p & ((uint64_t)0xff <<  8)) >>  8) & 0xff), (char)(((p & ((uint64_t)0xff <<  0)) >>  0) & 0xff) }

I tried to build some c++ code with cwebsocket but it failed.

I success to build when I add codes below in each header files

ifdef __cplusplus

extern "C" {

endif

// function definitions

ifdef __cplusplus

}

endif

and add ifndef in common.h

ifndef __cplusplus

typedef enum {
TRUE,
FALSE
} bool;

endif

cwebsocket_write_data doesn't work over 125 bytes payload message.

so I fix cwebsocket_write_data code and success to send 225 bytes text message.

[code]
// add opcode parameter
ssize_t cwebsocket_write_data(cwebsocket_client *websocket, const char *data, int len, opcode code) {

// change header_length code
uint32_t masking_length = 4;
uint32_t header_length = ((len <= 125) ? 2 : (len <= 65535 ? 4 : 10)) + masking_length;

// set opcode to header
header[0] = code | 0x80;

// change code for header[1] and remove increase header_length code
if(payload_len <= 125) {
header[1] = payload_len | 0x80;
header[2] = masking_key[0];
header[3] = masking_key[1];
header[4] = masking_key[2];
header[5] = masking_key[3];
}
else if(payload_len <= 65535) {
header[1] = 126 | 0x80;
header[2] = (payload_len >> 8) & 0xff;
header[3] = (payload_len >> 0) & 0xff;
header[4] = masking_key[0];
header[5] = masking_key[1];
header[6] = masking_key[2];
header[7] = masking_key[3];
}
else {
header[1] = 127 | 0x80;
header[2] = (payload_len >> 56) & 0xff;
header[3] = (payload_len >> 48) & 0xff;
header[4] = (payload_len >> 40) & 0xff;
header[5] = (payload_len >> 32) & 0xff;
header[6] = (payload_len >> 24) & 0xff;
header[7] = (payload_len >> 16) & 0xff;
header[8] = (payload_len >> 8) & 0xff;
header[9] = (payload_len >> 0) & 0xff;
header[10] = masking_key[0];
header[11] = masking_key[1];
header[12] = masking_key[2];
header[13] = masking_key[3];
}