make API const-safe
diff --git a/README b/README
index 838928e..fd217a2 100644
--- a/README
+++ b/README
@@ -95,7 +95,7 @@
IIb. Receiving Data
void libtelnet_push(libtelnet_t *telnet,
- unsigned char *buffer, unsigned int size, void *user_data);
+ const unsigned char *buffer, unsigned int size, void *user_data);
When your application receives data over the socket from the
remote end, it must pass the received bytes into this function.
@@ -132,13 +132,14 @@
LIBTELNET_DONT. The opt parameter is the option to
negotiate.
- void libtelnet_send_data(libtelnet_t *telnet, unsigned char *buffer,
- unsigned int size);
+ void libtelnet_send_data(libtelnet_t *telnet,
+ const unsigned char *buffer, unsigned int size);
Sends raw data, which would be either the process output from
a server or the user input from a client.
void libtelnet_send_subnegotiation(libtelnet_t *telnet,
- unsigned char telopt, unsigned char *buffer, unsigned int size);
+ unsigned char telopt, const unsigned char *buffer,
+ unsigned int size);
Sends a TELNET sub-negotiation command. The telopt parameter
is the sub-negotiation option.
@@ -172,7 +173,7 @@
pointer passed to libtelnet_init().
struct libtelnet_event_t {
- unsigned char *buffer;
+ const unsigned char *buffer;
unsigned int size;
libtelnet_event_type_t type;
unsigned char command;
diff --git a/libtelnet.c b/libtelnet.c
index 78e58e2..9688d24 100644
--- a/libtelnet.c
+++ b/libtelnet.c
@@ -48,8 +48,8 @@
/* event dispatch helper; return value is value of the accept field of the
* event struct after dispatch; used for the funky REQUEST event */
static int _event(libtelnet_t *telnet, libtelnet_event_type_t type,
- unsigned char command, unsigned char telopt, unsigned char *buffer,
- unsigned int size) {
+ unsigned char command, unsigned char telopt,
+ const unsigned char *buffer, unsigned int size) {
libtelnet_event_t ev;
ev.buffer = buffer;
ev.size = size;
@@ -126,7 +126,7 @@
}
/* push bytes out, compressing them first if need be */
-static void _send(libtelnet_t *telnet, unsigned char *buffer,
+static void _send(libtelnet_t *telnet, const unsigned char *buffer,
unsigned int size) {
#ifdef HAVE_ZLIB
/* if we have a deflate (compression) zlib box, use it */
@@ -135,7 +135,7 @@
int rs;
/* initialize z state */
- telnet->z->next_in = buffer;
+ telnet->z->next_in = (unsigned char *)buffer;
telnet->z->avail_in = size;
telnet->z->next_out = deflate_buffer;
telnet->z->avail_out = sizeof(deflate_buffer);
@@ -450,7 +450,7 @@
return LIBTELNET_EOK;
}
-static void _process(libtelnet_t *telnet, unsigned char *buffer,
+static void _process(libtelnet_t *telnet, const unsigned char *buffer,
unsigned int size) {
unsigned char byte;
unsigned int i, start;
@@ -610,7 +610,7 @@
}
/* push a bytes into the state tracker */
-void libtelnet_push(libtelnet_t *telnet, unsigned char *buffer,
+void libtelnet_push(libtelnet_t *telnet, const unsigned char *buffer,
unsigned int size) {
#ifdef HAVE_ZLIB
/* if we have an inflate (decompression) zlib stream, use it */
@@ -619,7 +619,7 @@
int rs;
/* initialize zlib state */
- telnet->z->next_in = buffer;
+ telnet->z->next_in = (unsigned char *)buffer;
telnet->z->avail_in = size;
telnet->z->next_out = inflate_buffer;
telnet->z->avail_out = sizeof(inflate_buffer);
@@ -792,10 +792,10 @@
}
/* send non-command data (escapes IAC bytes) */
-void libtelnet_send_data(libtelnet_t *telnet, unsigned char *buffer,
+void libtelnet_send_data(libtelnet_t *telnet, const unsigned char *buffer,
unsigned int size) {
- static unsigned char CRLF[] = { '\r', '\n' };
- static unsigned char CRNUL[] = { '\r', '\0' };
+ static const unsigned char CRLF[] = { '\r', '\n' };
+ static const unsigned char CRNUL[] = { '\r', '\0' };
unsigned int i, l;
for (l = i = 0; i != size; ++i) {
@@ -832,7 +832,7 @@
/* send sub-request */
void libtelnet_send_subnegotiation(libtelnet_t *telnet, unsigned char telopt,
- unsigned char *buffer, unsigned int size) {
+ const unsigned char *buffer, unsigned int size) {
libtelnet_send_telopt(telnet, LIBTELNET_SB, telopt);
libtelnet_send_data(telnet, buffer, size);
libtelnet_send_command(telnet, LIBTELNET_SE);
@@ -855,7 +855,7 @@
void libtelnet_begin_compress2(libtelnet_t *telnet) {
#ifdef HAVE_ZLIB
- unsigned char compress2[] = { LIBTELNET_IAC, LIBTELNET_SB,
+ static const unsigned char compress2[] = { LIBTELNET_IAC, LIBTELNET_SB,
LIBTELNET_TELOPT_COMPRESS2, LIBTELNET_IAC, LIBTELNET_SE };
/* attempt to create output stream first, bail if we can't */
diff --git a/libtelnet.h b/libtelnet.h
index a129438..a8bf4da 100644
--- a/libtelnet.h
+++ b/libtelnet.h
@@ -137,7 +137,7 @@
/* event information */
struct libtelnet_event_t {
/* data buffer: for DATA, SEND, SUBNEGOTIATION, and ERROR events */
- unsigned char *buffer;
+ const unsigned char *buffer;
unsigned int size;
/* type of event */
enum libtelnet_event_type_t type;
@@ -195,7 +195,7 @@
extern void libtelnet_free(libtelnet_t *telnet);
/* push a byte buffer into the state tracker */
-extern void libtelnet_push(libtelnet_t *telnet, unsigned char *buffer,
+extern void libtelnet_push(libtelnet_t *telnet, const unsigned char *buffer,
unsigned int size);
/* send an iac command */
@@ -213,8 +213,8 @@
unsigned char opt);
/* send non-command data (escapes IAC bytes) */
-extern void libtelnet_send_data(libtelnet_t *telnet, unsigned char *buffer,
- unsigned int size);
+extern void libtelnet_send_data(libtelnet_t *telnet,
+ const unsigned char *buffer, unsigned int size);
/* send sub-request, equivalent to:
* libtelnet_send_telopt(telnet, LIBTELNET_SB, telopt)
@@ -224,7 +224,7 @@
* thare are most easily implemented with a series of send_data calls.
*/
extern void libtelnet_send_subnegotiation(libtelnet_t *telnet,
- unsigned char telopt, unsigned char *buffer, unsigned int size);
+ unsigned char telopt, const unsigned char *buffer, unsigned int size);
/* begin sending compressed data (server only) */
extern void libtelnet_begin_compress2(libtelnet_t *telnet);
diff --git a/telnet-chatd.c b/telnet-chatd.c
deleted file mode 100644
index 67cbe8d..0000000
--- a/telnet-chatd.c
+++ /dev/null
@@ -1,327 +0,0 @@
-/*
- * 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_send_printf(&users[i].telnet, "%s: %s\r\n",
- from, msg);
- }
- }
-}
-
-static void _send(int sock, 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_send_printf(&user->telnet,
- "Invalid name.\r\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_send_printf(&user->telnet,
- "Name in use.\r\nEnter name: ");
- return;
- }
- }
-
- /* keep name */
- user->name = strdup(line);
- libtelnet_send_printf(&user->telnet, "Welcome, %s!\r\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, 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_send_printf(&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;
-}
diff --git a/telnet-client.c b/telnet-client.c
index ef1b8e6..e801611 100644
--- a/telnet-client.c
+++ b/telnet-client.c
@@ -57,7 +57,7 @@
}
}
-static void _send(int sock, unsigned char *buffer, unsigned int size) {
+static void _send(int sock, const unsigned char *buffer, unsigned int size) {
int rs;
/* send data */
diff --git a/telnet-proxy.c b/telnet-proxy.c
index f767188..e8f2661 100644
--- a/telnet-proxy.c
+++ b/telnet-proxy.c
@@ -129,7 +129,7 @@
}
}
-static void print_buffer(unsigned char *buffer, unsigned int size) {
+static void print_buffer(const unsigned char *buffer, unsigned int size) {
unsigned int i;
for (i = 0; i != size; ++i) {
if (buffer[i] == ' ' || (isprint(buffer[i]) && !isspace(buffer[i])))
@@ -142,7 +142,7 @@
}
}
-static void _send(int sock, unsigned char *buffer, unsigned int size) {
+static void _send(int sock, const unsigned char *buffer, unsigned int size) {
int rs;
/* send data */