added libtelnet_printf2 which does CRLF automagic stuff

This commit is contained in:
Sean Middleditch 2009-03-16 17:10:58 -04:00
parent 4a1240e2a7
commit 4a15604d10
3 changed files with 371 additions and 2 deletions

View File

@ -858,7 +858,7 @@ void libtelnet_begin_compress2(libtelnet_t *telnet) {
}
/* send formatted data through libtelnet_send_data */
int libtelnet_send_printf(libtelnet_t *telnet, const char *fmt, ...) {
int libtelnet_printf(libtelnet_t *telnet, const char *fmt, ...) {
char buffer[4096];
va_list va;
int rs;
@ -873,3 +873,45 @@ int libtelnet_send_printf(libtelnet_t *telnet, const char *fmt, ...) {
return rs;
}
/* send formatted data with \r and \n translation in addition to IAC IAC */
int libtelnet_printf2(libtelnet_t *telnet, const char *fmt, ...) {
static const unsigned char CRLF[] = { '\r', '\n' };
static const unsigned char CRNUL[] = { '\r', '\0' };
char buffer[4096];
va_list va;
int rs, i, l;
/* format */
va_start(va, fmt);
rs = vsnprintf(buffer, sizeof(buffer), fmt, va);
va_end(va);
/* send */
for (l = i = 0; i != rs; ++i) {
/* special characters */
if (buffer[i] == LIBTELNET_IAC || buffer[i] == '\r' ||
buffer[i] == '\n') {
/* dump prior portion of text */
if (i != l)
_send(telnet, (unsigned char *)buffer + l, i - l);
l = i + 1;
/* IAC -> IAC IAC */
if (buffer[i] == LIBTELNET_IAC)
libtelnet_send_command(telnet, LIBTELNET_IAC);
/* automatic translation of \r -> CRNUL */
else if (buffer[i] == '\r')
_send(telnet, CRNUL, 2);
/* automatic translation of \n -> CRLF */
else if (buffer[i] == '\n')
_send(telnet, CRLF, 2);
}
}
/* send whatever portion of buffer is left */
if (i != l)
_send(telnet, (unsigned char *)buffer + l, i - l);
return rs;
}

View File

@ -235,6 +235,9 @@ extern void libtelnet_begin_compress2(libtelnet_t *telnet);
# define LIBTELNET_GNU_PRINTF(f,a)
#endif
extern int libtelnet_send_printf(libtelnet_t *telnet, const char *fmt, ...);
extern int libtelnet_printf(libtelnet_t *telnet, const char *fmt, ...);
/* send formatted data with \r and \n translated */
extern int libtelnet_printf2(libtelnet_t *telnet, const char *fmt, ...);
#endif /* !defined(LIBTELNET_INCLUDE) */

324
telnet-chatd.c Normal file
View File

@ -0,0 +1,324 @@
/*
* Sean Middleditch
* sean@sourcemud.org
*
* The author or authors of this code dedicate any and all copyright interest
* in this code to the public domain. We make this dedication for the benefit
* of the public at large and to the detriment of our heirs and successors. We
* intend this dedication to be an overt act of relinquishment in perpetuity of
* all present and future rights to this code under copyright law.
*/
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <poll.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <unistd.h>
#ifdef HAVE_ZLIB
#include "zlib.h"
#endif
#include "libtelnet.h"
#define MAX_USERS 64
#define LINEBUFFER_SIZE 256
struct user_t {
char *name;
int sock;
libtelnet_t telnet;
char linebuf[256];
int linepos;
};
static struct user_t users[MAX_USERS];
static void linebuffer_push(char *buffer, size_t size, int *linepos,
char ch, void (*cb)(const char *line, int overflow, void *ud),
void *ud) {
/* CRLF -- line terminator */
if (ch == '\n' && *linepos > 0 && buffer[*linepos - 1] == '\r') {
/* NUL terminate (replaces \r in buffer), notify app, clear */
buffer[*linepos - 1] = 0;
cb(buffer, 0, ud);
*linepos = 0;
/* CRNUL -- just a CR */
} else if (ch == 0 && *linepos > 0 && buffer[*linepos - 1] == '\r') {
/* do nothing, the CR is already in the buffer */
/* anything else (including technically invalid CR followed by
* anything besides LF or NUL -- just buffer if we have room
* \r
*/
} else if (*linepos != size) {
buffer[(*linepos)++] = ch;
/* buffer overflow */
} else {
/* terminate (NOTE: eats a byte), notify app, clear buffer */
buffer[size - 1] = 0;
cb(buffer, size - 1, ud);
*linepos = 0;
}
}
static void _message(const char *from, const char *msg) {
int i;
for (i = 0; i != MAX_USERS; ++i) {
if (users[i].sock != -1) {
libtelnet_printf2(&users[i].telnet, "%s: %s\n", from, msg);
}
}
}
static void _send(int sock, const unsigned char *buffer, unsigned int size) {
int rs;
/* ignore on invalid socket */
if (sock == -1)
return;
/* send data */
while (size > 0) {
if ((rs = send(sock, buffer, size, 0)) == -1) {
if (errno != EINTR && errno != ECONNRESET) {
fprintf(stderr, "send() failed: %s\n", strerror(errno));
exit(1);
} else {
return;
}
} else if (rs == 0) {
fprintf(stderr, "send() unexpectedly returned 0\n");
exit(1);
}
/* update pointer and size to see if we've got more to send */
buffer += rs;
size -= rs;
}
}
/* process input line */
static void _online(const char *line, int overflow, void *ud) {
struct user_t *user = (struct user_t*)ud;
int i;
/* if the user has no name, this is his "login" */
if (user->name == 0) {
/* must not be empty, must be at least 32 chars */
if (strlen(line) == 0 || strlen(line) > 32) {
libtelnet_printf2(&user->telnet, "Invalid name.\nEnter name: ");
return;
}
/* must not already be in use */
for (i = 0; i != MAX_USERS; ++i) {
if (users[i].name != 0 && strcmp(users[i].name, line) == 0) {
libtelnet_printf2(&user->telnet, "Name in use.\nEnter name: ");
return;
}
}
/* keep name */
user->name = strdup(line);
libtelnet_printf2(&user->telnet, "Welcome, %s!\n", line);
return;
}
/* if line is "quit" then, well, quit */
if (strcmp(line, "quit") == 0) {
close(user->sock);
user->sock = -1;
_message(user->name, "** HAS QUIT **");
free(user->name);
user->name = 0;
return;
}
/* just a message -- send to all users */
_message(user->name, line);
}
static void _input(struct user_t *user, const unsigned char *buffer,
unsigned int size) {
unsigned int i;
for (i = 0; i != size; ++i)
linebuffer_push(user->linebuf, sizeof(user->linebuf), &user->linepos,
(char)buffer[i], _online, user);
}
static void _event_handler(libtelnet_t *telnet, libtelnet_event_t *ev,
void *user_data) {
struct user_t *user = (struct user_t*)user_data;
switch (ev->type) {
/* data received */
case LIBTELNET_EV_DATA:
_input(user, ev->buffer, ev->size);
break;
/* data must be sent */
case LIBTELNET_EV_SEND:
_send(user->sock, ev->buffer, ev->size);
break;
/* error */
case LIBTELNET_EV_ERROR:
close(user->sock);
user->sock = -1;
if (user->name != 0) {
_message(user->name, "** HAS HAD AN ERROR **");
free(user->name);
user->name = 0;
}
libtelnet_free(&user->telnet);
break;
default:
/* ignore */
break;
}
}
int main(int argc, char **argv) {
unsigned char buffer[512];
short listen_port;
int listen_sock;
int rs;
int i;
struct sockaddr_in addr;
socklen_t addrlen;
struct pollfd pfd[MAX_USERS + 1];
/* check usage */
if (argc != 2) {
fprintf(stderr, "Usage:\n ./telnet-chatd <port>\n");
return 1;
}
/* initialize data structures */
memset(&pfd, 0, sizeof(pfd));
memset(users, 0, sizeof(users));
for (i = 0; i != MAX_USERS; ++i)
users[i].sock = -1;
/* parse listening port */
listen_port = strtol(argv[1], 0, 10);
/* create listening socket */
if ((listen_sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
fprintf(stderr, "socket() failed: %s\n", strerror(errno));
return 1;
}
/* reuse address option */
rs = 1;
setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &rs, sizeof(rs));
/* bind to listening addr/port */
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = INADDR_ANY;
addr.sin_port = htons(listen_port);
if (bind(listen_sock, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
fprintf(stderr, "bind() failed: %s\n", strerror(errno));
return 1;
}
/* listen for clients */
if (listen(listen_sock, 5) == -1) {
fprintf(stderr, "listen() failed: %s\n", strerror(errno));
return 1;
}
printf("LISTENING ON PORT %d\n", listen_port);
/* initialize listening descriptors */
pfd[MAX_USERS].fd = listen_sock;
pfd[MAX_USERS].events = POLLIN;
/* loop for ever */
for (;;) {
/* prepare for poll */
for (i = 0; i != MAX_USERS; ++i) {
if (users[i].sock != -1) {
pfd[i].fd = users[i].sock;
pfd[i].events = POLLIN;
} else {
pfd[i].fd = -1;
pfd[i].events = 0;
}
}
/* poll */
rs = poll(pfd, MAX_USERS + 1, -1);
if (rs == -1 && errno != EINTR) {
fprintf(stderr, "poll() failed: %s\n", strerror(errno));
return 1;
}
/* new connection */
if (pfd[MAX_USERS].revents & POLLIN) {
/* acept the sock */
addrlen = sizeof(addr);
if ((rs = accept(listen_sock, (struct sockaddr *)&addr,
&addrlen)) == -1) {
fprintf(stderr, "accept() failed: %s\n", strerror(errno));
return 1;
}
printf("Connection received.\n");
/* find a free user */
for (i = 0; i != MAX_USERS; ++i)
if (users[i].sock == -1)
break;
if (i == MAX_USERS) {
printf(" rejected (too many users)\n");
_send(rs, (unsigned char *)"Too many users.\r\n", 14);
close(rs);
}
/* init, welcome */
users[i].sock = rs;
libtelnet_init(&users[i].telnet, _event_handler, 0, &users[i]);
libtelnet_printf2(&users[i].telnet, "Enter name: ");
}
/* read from client */
for (i = 0; i != MAX_USERS; ++i) {
/* skip users that aren't actually connected */
if (users[i].sock == -1)
continue;
if (pfd[i].revents & POLLIN) {
if ((rs = recv(users[i].sock, buffer, sizeof(buffer), 0)) > 0) {
libtelnet_push(&users[i].telnet, buffer, rs);
} else if (rs == 0) {
printf("Connection closed.\n");
close(users[i].sock);
if (users[i].name != 0) {
_message(users[i].name, "** HAS DISCONNECTED **");
free(users[i].name);
users[i].name = 0;
}
libtelnet_free(&users[i].telnet);
users[i].sock = -1;
break;
} else if (errno != EINTR) {
fprintf(stderr, "recv(client) failed: %s\n",
strerror(errno));
exit(1);
}
}
}
}
/* not that we can reach this, but GCC will cry if it's not here */
return 0;
}