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authorRaymaekers Luca <raymaekers.luca@gmail.com>2024-10-24 23:10:31 +0200
committerRaymaekers Luca <raymaekers.luca@gmail.com>2024-10-24 23:10:31 +0200
commitf37cce374cc9da243fc2babbea9a7051f15db80a (patch)
tree7a6b0e5f7bd38cbd39ba1e1f43689ca6be92c53e /common.h
parentc7687f88bc5cb4d25304b0ee19789c37aebd7b6d (diff)
Archive code into v1/ directory
The code was written too fast and I deemed that it would be better to make a new draft.
Diffstat (limited to 'common.h')
-rw-r--r--common.h179
1 files changed, 0 insertions, 179 deletions
diff --git a/common.h b/common.h
deleted file mode 100644
index e220735..0000000
--- a/common.h
+++ /dev/null
@@ -1,179 +0,0 @@
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/socket.h>
-#include <unistd.h>
-
-#define PORT 9983
-// max buffer size sent over network
-// TODO: choose a better size
-#define BUF_MAX 256
-// max size for a message sent
-#define MESSAGE_MAX 256
-// max length of author field
-#define MESSAGE_AUTHOR_LEN 12
-// max length of timestamp field
-#define MESSAGE_TIMESTAMP_LEN 9
-// current user's name
-#define USERNAME "Jef Koek"
-
-typedef uint8_t u8;
-typedef uint16_t u16;
-typedef uint32_t u32;
-
-// To serialize the text that could be arbitrary length the lenght is encoded after the author
-// string and before the text.
-struct message {
- char author[MESSAGE_AUTHOR_LEN];
- char timestamp[MESSAGE_TIMESTAMP_LEN]; // HH:MM:SS
- u16 len; // length of the text including null terminator
- char *text;
-};
-
-// printf without buffering using write syscall, works when using sockets
-void writef(char *format, ...);
-
-u16 str_len(char *str);
-void str_cpy(char *to, char *from);
-
-// save the message msg to file in binary format, returns zero on success, returns 1 if the msg.text
-// was empty which should not be allowed.
-u8 save_message(struct message *msg, FILE *f);
-// load the message msg from file f, returns zero on success, returns 1 if the msg.text
-// was empty which should not be allowed.
-u8 load_message(struct message *msg, FILE *f);
-
-// Send a stream of bytes containing msg
-// return -1 if send() returns -1. Otherwise returns number of bytes sent.
-u32 send_message(struct message msg, u32 serverfd);
-// Receives a stream of bytes and populates msg with the data received
-// if recv() returns 0 or -1 it will return early and return 0 or -1 accordingly.
-// Otherwise returns the number of bytes received
-u32 receive_message(struct message *msg, u32 clientfd);
-
-void writef(char *format, ...)
-{
- char buf[255 + 1];
- va_list args;
- va_start(args, format);
-
- vsnprintf(buf, sizeof(buf), format, args);
- va_end(args);
-
- int n = 0;
- while (*(buf + n) != 0)
- n++;
- write(0, buf, n);
-}
-
-// Returns the length of the string plus the null terminator
-u16 str_len(char *str)
-{
- if (*str == 0)
- return 0;
-
- u16 i = 0;
- while (str[i])
- i++;
-
- return i + 1;
-}
-
-void str_cpy(char *to, char *from)
-{
- while ((*to++ = *from++))
- ;
-}
-
-// Save msg to file f
-// Returns 0 on success, returns 1 if msg->text is NULL, returns 2 if mfg->len is 0
-u8 save_message(struct message *msg, FILE *f)
-{
- if (msg->text == NULL) {
- return 1;
- } else if (msg->len == 0)
- return 2;
-
- fwrite(&msg->timestamp, sizeof(*msg->timestamp) * MESSAGE_TIMESTAMP_LEN, 1, f);
- fwrite(&msg->author, sizeof(*msg->author) * MESSAGE_AUTHOR_LEN, 1, f);
- fwrite(&msg->len, sizeof(msg->len), 1, f);
- fputs(msg->text, f);
-
- return 0;
-}
-
-u8 load_message(struct message *msg, FILE *f)
-{
- fread(msg, sizeof(*msg->timestamp) * MESSAGE_TIMESTAMP_LEN + sizeof(*msg->author) * MESSAGE_AUTHOR_LEN, 1, f);
- u16 len;
- fread(&len, sizeof(len), 1, f);
- if (len == 0) {
- // TODO: Error: empty message should not be allowed
- // empty message
- msg->text = "";
- return 1;
- }
- char txt[len];
- fgets(txt, len, f);
- msg->text = txt;
-
- return 0;
-}
-
-u32 send_message(struct message msg, u32 serverfd)
-{
- // stream length : message author : message timestamp : message text + \0
- u32 buf_len = sizeof(buf_len) + MESSAGE_AUTHOR_LEN + MESSAGE_TIMESTAMP_LEN + msg.len;
- char buf[buf_len];
- u32 offset;
-
- memcpy(buf, &buf_len, sizeof(buf_len));
- offset = sizeof(buf_len);
- memcpy(buf + offset, msg.author, MESSAGE_AUTHOR_LEN);
- offset += MESSAGE_AUTHOR_LEN;
- memcpy(buf + offset, msg.timestamp, MESSAGE_TIMESTAMP_LEN);
- offset += MESSAGE_TIMESTAMP_LEN;
- memcpy(buf + offset, msg.text, msg.len);
-
- u32 n = send(serverfd, &buf, buf_len, 0);
- if (n == -1)
- return n;
-
- writef("%d bytes sent.\n", n);
- return n;
-}
-
-u32 receive_message(struct message *msg, u32 clientfd)
-{
- // must all be of the s
- u32 nrecv, buf_len;
- // limit on what can be received with recv()
- u32 buf_size = 20;
- // temporary buffer to receive message data over a stream
- char recv_buf[BUF_MAX];
-
- nrecv = recv(clientfd, recv_buf, buf_size, 0);
- if (nrecv == 0 || nrecv == -1)
- return nrecv;
-
- memcpy(&buf_len, recv_buf, sizeof(buf_len));
-
- u32 i = 0;
- while (nrecv < buf_len) {
- // advance the copying by the amounts of bytes received each time
- i = recv(clientfd, recv_buf + nrecv, buf_size, 0);
- if (i == 0 || i == -1)
- return nrecv;
- nrecv += i;
- }
-
- struct message received = {0};
- memcpy(&received, recv_buf + sizeof(buf_len), MESSAGE_AUTHOR_LEN + MESSAGE_TIMESTAMP_LEN);
- received.text = recv_buf + sizeof(buf_len) + MESSAGE_AUTHOR_LEN + MESSAGE_TIMESTAMP_LEN;
- received.len = buf_len - sizeof(buf_len) - MESSAGE_AUTHOR_LEN - MESSAGE_TIMESTAMP_LEN;
-
- // assume clientfd is serverfd + 1;
- writef("Received %d bytes from client(%d): %s [%s] (%d)%s\n", nrecv, clientfd - 3, received.timestamp, received.author, received.len, received.text);
- return nrecv;
-}