hush: remove superfluous assignment
[oweals/busybox.git] / networking / telnet.c
index 3a06c167c94037d6ffcb0731231c49fdee7bcbc8..77e17479d75f0dc71054b1671983bcab75a86cd9 100644 (file)
@@ -21,7 +21,6 @@
  *
  */
 
-#include <termios.h>
 #include <arpa/telnet.h>
 #include <netinet/in.h>
 #include "libbb.h"
@@ -52,14 +51,14 @@ enum {
 
 typedef unsigned char byte;
 
+enum { netfd = 3 };
+
 struct globals {
-       int     netfd; /* console fd:s are 0 and 1 (and 2) */
-       short   iaclen; /* could even use byte */
+       int     iaclen; /* could even use byte, but it's a loss on x86 */
        byte    telstate; /* telnet negotiation state from network input */
        byte    telwish;  /* DO, DONT, WILL, WONT */
        byte    charmode;
        byte    telflags;
-       byte    gotsig;
        byte    do_termios;
 #if ENABLE_FEATURE_TELNET_TTYPE
        char    *ttype;
@@ -78,11 +77,10 @@ struct globals {
        struct termios termios_raw;
 };
 #define G (*(struct globals*)&bb_common_bufsiz1)
-void BUG_telnet_globals_too_big(void);
 #define INIT_G() do { \
-       if (sizeof(G) > COMMON_BUFSIZE) \
-               BUG_telnet_globals_too_big(); \
-       /* memset(&G, 0, sizeof G); - already is */ \
+       struct G_sizecheck { \
+               char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
+       }; \
 } while (0)
 
 /* Function prototypes */
@@ -93,26 +91,26 @@ static void will_charmode(void);
 static void telopt(byte c);
 static int subneg(byte c);
 
-static void iacflush(void)
+static void iac_flush(void)
 {
-       write(G.netfd, G.iacbuf, G.iaclen);
+       write(netfd, G.iacbuf, G.iaclen);
        G.iaclen = 0;
 }
 
 #define write_str(fd, str) write(fd, str, sizeof(str) - 1)
 
-static void doexit(int ev) ATTRIBUTE_NORETURN;
+static void doexit(int ev) NORETURN;
 static void doexit(int ev)
 {
        cookmode();
        exit(ev);
 }
 
-static void conescape(void)
+static void con_escape(void)
 {
        char b;
 
-       if (G.gotsig)   /* came from line  mode... go raw */
+       if (bb_got_signal) /* came from line mode... go raw */
                rawmode();
 
        write_str(1, "\r\nConsole escape. Commands are:\r\n\n"
@@ -126,15 +124,15 @@ static void conescape(void)
 
        switch (b) {
        case 'l':
-               if (!G.gotsig) {
+               if (!bb_got_signal) {
                        do_linemode();
-                       goto rrturn;
+                       goto ret;
                }
                break;
        case 'c':
-               if (G.gotsig) {
+               if (bb_got_signal) {
                        will_charmode();
-                       goto rrturn;
+                       goto ret;
                }
                break;
        case 'z':
@@ -148,15 +146,14 @@ static void conescape(void)
 
        write_str(1, "continuing...\r\n");
 
-       if (G.gotsig)
+       if (bb_got_signal)
                cookmode();
-
- rrturn:
-       G.gotsig = 0;
+ ret:
+       bb_got_signal = 0;
 
 }
 
-static void handlenetoutput(int len)
+static void handle_net_output(int len)
 {
        /* here we could do smart tricks how to handle 0xFF:s in output
         * stream like writing twice every sequence of FF:s (thus doing
@@ -169,19 +166,19 @@ static void handlenetoutput(int len)
         * first - I cannot use programs like sz/rz
         * second - the 0x0D is sent as one character and if the next
         *      char is 0x0A then it's eaten by a server side.
-        * third - whay doy you have to make 'many write()s'?
+        * third - why do you have to make 'many write()s'?
         *      I don't understand.
-        * So I implemented it. It's realy useful for me. I hope that
-        * others people will find it interesting too.
+        * So I implemented it. It's really useful for me. I hope that
+        * other people will find it interesting too.
         */
 
        int i, j;
-       byte * p = (byte*)G.buf;
+       byte *p = (byte*)G.buf;
        byte outbuf[4*DATABUFSIZE];
 
        for (i = len, j = 0; i > 0; i--, p++) {
                if (*p == 0x1d) {
-                       conescape();
+                       con_escape();
                        return;
                }
                outbuf[j++] = *p;
@@ -191,10 +188,10 @@ static void handlenetoutput(int len)
                        outbuf[j++] = 0x00;
        }
        if (j > 0)
-               write(G.netfd, outbuf, j);
+               write(netfd, outbuf, j);
 }
 
-static void handlenetinput(int len)
+static void handle_net_input(int len)
 {
        int i;
        int cstart = 0;
@@ -207,51 +204,54 @@ static void handlenetinput(int len)
                                cstart = i;
                                G.telstate = TS_IAC;
                        }
-               } else
-                       switch (G.telstate) {
-                       case TS_0:
-                               if (c == IAC)
-                                       G.telstate = TS_IAC;
-                               else
-                                       G.buf[cstart++] = c;
-                               break;
+                       continue;
+               }
+               switch (G.telstate) {
+               case TS_0:
+                       if (c == IAC)
+                               G.telstate = TS_IAC;
+                       else
+                               G.buf[cstart++] = c;
+                       break;
 
-                       case TS_IAC:
-                               if (c == IAC) { /* IAC IAC -> 0xFF */
-                                       G.buf[cstart++] = c;
-                                       G.telstate = TS_0;
-                                       break;
-                               }
-                               /* else */
-                               switch (c) {
-                               case SB:
-                                       G.telstate = TS_SUB1;
-                                       break;
-                               case DO:
-                               case DONT:
-                               case WILL:
-                               case WONT:
-                                       G.telwish =  c;
-                                       G.telstate = TS_OPT;
-                                       break;
-                               default:
-                                       G.telstate = TS_0;      /* DATA MARK must be added later */
-                               }
-                               break;
-                       case TS_OPT: /* WILL, WONT, DO, DONT */
-                               telopt(c);
+               case TS_IAC:
+                       if (c == IAC) { /* IAC IAC -> 0xFF */
+                               G.buf[cstart++] = c;
                                G.telstate = TS_0;
                                break;
-                       case TS_SUB1: /* Subnegotiation */
-                       case TS_SUB2: /* Subnegotiation */
-                               if (subneg(c))
-                                       G.telstate = TS_0;
+                       }
+                       /* else */
+                       switch (c) {
+                       case SB:
+                               G.telstate = TS_SUB1;
+                               break;
+                       case DO:
+                       case DONT:
+                       case WILL:
+                       case WONT:
+                               G.telwish =  c;
+                               G.telstate = TS_OPT;
                                break;
+                       default:
+                               G.telstate = TS_0;      /* DATA MARK must be added later */
                        }
+                       break;
+               case TS_OPT: /* WILL, WONT, DO, DONT */
+                       telopt(c);
+                       G.telstate = TS_0;
+                       break;
+               case TS_SUB1: /* Subnegotiation */
+               case TS_SUB2: /* Subnegotiation */
+                       if (subneg(c))
+                               G.telstate = TS_0;
+                       break;
+               }
        }
        if (G.telstate) {
-               if (G.iaclen) iacflush();
-               if (G.telstate == TS_0) G.telstate = 0;
+               if (G.iaclen)
+                       iac_flush();
+               if (G.telstate == TS_0)
+                       G.telstate = 0;
                len = cstart;
        }
 
@@ -259,87 +259,87 @@ static void handlenetinput(int len)
                write(STDOUT_FILENO, G.buf, len);
 }
 
-static void putiac(int c)
+static void put_iac(int c)
 {
        G.iacbuf[G.iaclen++] = c;
 }
 
-static void putiac2(byte wwdd, byte c)
+static void put_iac2(byte wwdd, byte c)
 {
        if (G.iaclen + 3 > IACBUFSIZE)
-               iacflush();
+               iac_flush();
 
-       putiac(IAC);
-       putiac(wwdd);
-       putiac(c);
+       put_iac(IAC);
+       put_iac(wwdd);
+       put_iac(c);
 }
 
 #if ENABLE_FEATURE_TELNET_TTYPE
-static void putiac_subopt(byte c, char *str)
+static void put_iac_subopt(byte c, char *str)
 {
-       int     len = strlen(str) + 6;   // ( 2 + 1 + 1 + strlen + 2 )
+       int len = strlen(str) + 6;   // ( 2 + 1 + 1 + strlen + 2 )
 
        if (G.iaclen + len > IACBUFSIZE)
-               iacflush();
+               iac_flush();
 
-       putiac(IAC);
-       putiac(SB);
-       putiac(c);
-       putiac(0);
+       put_iac(IAC);
+       put_iac(SB);
+       put_iac(c);
+       put_iac(0);
 
        while (*str)
-               putiac(*str++);
+               put_iac(*str++);
 
-       putiac(IAC);
-       putiac(SE);
+       put_iac(IAC);
+       put_iac(SE);
 }
 #endif
 
 #if ENABLE_FEATURE_TELNET_AUTOLOGIN
-static void putiac_subopt_autologin(void)
+static void put_iac_subopt_autologin(void)
 {
        int len = strlen(G.autologin) + 6;      // (2 + 1 + 1 + strlen + 2)
        const char *user = "USER";
 
        if (G.iaclen + len > IACBUFSIZE)
-               iacflush();
+               iac_flush();
 
-       putiac(IAC);
-       putiac(SB);
-       putiac(TELOPT_NEW_ENVIRON);
-       putiac(TELQUAL_IS);
-       putiac(NEW_ENV_VAR);
+       put_iac(IAC);
+       put_iac(SB);
+       put_iac(TELOPT_NEW_ENVIRON);
+       put_iac(TELQUAL_IS);
+       put_iac(NEW_ENV_VAR);
 
        while (*user)
-               putiac(*user++);
+               put_iac(*user++);
 
-       putiac(NEW_ENV_VALUE);
+       put_iac(NEW_ENV_VALUE);
 
        while (*G.autologin)
-               putiac(*G.autologin++);
+               put_iac(*G.autologin++);
 
-       putiac(IAC);
-       putiac(SE);
+       put_iac(IAC);
+       put_iac(SE);
 }
 #endif
 
 #if ENABLE_FEATURE_AUTOWIDTH
-static void putiac_naws(byte c, int x, int y)
+static void put_iac_naws(byte c, int x, int y)
 {
        if (G.iaclen + 9 > IACBUFSIZE)
-               iacflush();
+               iac_flush();
 
-       putiac(IAC);
-       putiac(SB);
-       putiac(c);
+       put_iac(IAC);
+       put_iac(SB);
+       put_iac(c);
 
-       putiac((x >> 8) & 0xff);
-       putiac(x & 0xff);
-       putiac((y >> 8) & 0xff);
-       putiac(y & 0xff);
+       put_iac((x >> 8) & 0xff);
+       put_iac(x & 0xff);
+       put_iac((y >> 8) & 0xff);
+       put_iac(y & 0xff);
 
-       putiac(IAC);
-       putiac(SE);
+       put_iac(IAC);
+       put_iac(SE);
 }
 #endif
 
@@ -368,9 +368,9 @@ static void will_charmode(void)
        G.telflags |= (UF_ECHO | UF_SGA);
        setConMode();
 
-       putiac2(DO, TELOPT_ECHO);
-       putiac2(DO, TELOPT_SGA);
-       iacflush();
+       put_iac2(DO, TELOPT_ECHO);
+       put_iac2(DO, TELOPT_SGA);
+       iac_flush();
 }
 
 static void do_linemode(void)
@@ -379,24 +379,24 @@ static void do_linemode(void)
        G.telflags &= ~(UF_ECHO | UF_SGA);
        setConMode();
 
-       putiac2(DONT, TELOPT_ECHO);
-       putiac2(DONT, TELOPT_SGA);
-       iacflush();
+       put_iac2(DONT, TELOPT_ECHO);
+       put_iac2(DONT, TELOPT_SGA);
+       iac_flush();
 }
 
 static void to_notsup(char c)
 {
        if (G.telwish == WILL)
-               putiac2(DONT, c);
+               put_iac2(DONT, c);
        else if (G.telwish == DO)
-               putiac2(WONT, c);
+               put_iac2(WONT, c);
 }
 
 static void to_echo(void)
 {
        /* if server requests ECHO, don't agree */
        if (G.telwish == DO) {
-               putiac2(WONT, TELOPT_ECHO);
+               put_iac2(WONT, TELOPT_ECHO);
                return;
        }
        if (G.telwish == DONT)
@@ -412,9 +412,9 @@ static void to_echo(void)
                G.telflags ^= UF_ECHO;
 
        if (G.telflags & UF_ECHO)
-               putiac2(DO, TELOPT_ECHO);
+               put_iac2(DO, TELOPT_ECHO);
        else
-               putiac2(DONT, TELOPT_ECHO);
+               put_iac2(DONT, TELOPT_ECHO);
 
        setConMode();
        write_str(1, "\r\n");  /* sudden modec */
@@ -432,9 +432,9 @@ static void to_sga(void)
 
        G.telflags ^= UF_SGA; /* toggle */
        if (G.telflags & UF_SGA)
-               putiac2(DO, TELOPT_SGA);
+               put_iac2(DO, TELOPT_SGA);
        else
-               putiac2(DONT, TELOPT_SGA);
+               put_iac2(DONT, TELOPT_SGA);
 }
 
 #if ENABLE_FEATURE_TELNET_TTYPE
@@ -443,9 +443,9 @@ static void to_ttype(void)
        /* Tell server we will (or won't) do TTYPE */
 
        if (G.ttype)
-               putiac2(WILL, TELOPT_TTYPE);
+               put_iac2(WILL, TELOPT_TTYPE);
        else
-               putiac2(WONT, TELOPT_TTYPE);
+               put_iac2(WONT, TELOPT_TTYPE);
 }
 #endif
 
@@ -455,9 +455,9 @@ static void to_new_environ(void)
        /* Tell server we will (or will not) do AUTOLOGIN */
 
        if (G.autologin)
-               putiac2(WILL, TELOPT_NEW_ENVIRON);
+               put_iac2(WILL, TELOPT_NEW_ENVIRON);
        else
-               putiac2(WONT, TELOPT_NEW_ENVIRON);
+               put_iac2(WONT, TELOPT_NEW_ENVIRON);
 }
 #endif
 
@@ -465,7 +465,7 @@ static void to_new_environ(void)
 static void to_naws(void)
 {
        /* Tell server we will do NAWS */
-       putiac2(WILL, TELOPT_NAWS);
+       put_iac2(WILL, TELOPT_NAWS);
 }
 #endif
 
@@ -487,7 +487,7 @@ static void telopt(byte c)
 #if ENABLE_FEATURE_AUTOWIDTH
        case TELOPT_NAWS:
                to_naws();
-               putiac_naws(c, G.win_width, G.win_height);
+               put_iac_naws(c, G.win_width, G.win_height);
                break;
 #endif
        default:
@@ -506,12 +506,12 @@ static int subneg(byte c)
 #if ENABLE_FEATURE_TELNET_TTYPE
                else
                if (c == TELOPT_TTYPE)
-                       putiac_subopt(TELOPT_TTYPE, G.ttype);
+                       put_iac_subopt(TELOPT_TTYPE, G.ttype);
 #endif
 #if ENABLE_FEATURE_TELNET_AUTOLOGIN
                else
                if (c == TELOPT_NEW_ENVIRON)
-                       putiac_subopt_autologin();
+                       put_iac_subopt_autologin();
 #endif
                break;
        case TS_SUB2:
@@ -523,12 +523,6 @@ static int subneg(byte c)
        return FALSE;
 }
 
-static void fgotsig(int sig)
-{
-       G.gotsig = sig;
-}
-
-
 static void rawmode(void)
 {
        if (G.do_termios)
@@ -545,7 +539,7 @@ static void cookmode(void)
 #define USE_POLL 1
 
 int telnet_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int telnet_main(int argc, char **argv)
+int telnet_main(int argc UNUSED_PARAM, char **argv)
 {
        char *host;
        int port;
@@ -573,9 +567,6 @@ int telnet_main(int argc, char **argv)
                cfmakeraw(&G.termios_raw);
        }
 
-       if (argc < 2)
-               bb_show_usage();
-
 #if ENABLE_FEATURE_TELNET_AUTOLOGIN
        if (1 & getopt32(argv, "al:", &G.autologin))
                G.autologin = getenv("USER");
@@ -590,20 +581,20 @@ int telnet_main(int argc, char **argv)
        if (*argv) /* extra params?? */
                bb_show_usage();
 
-       G.netfd = create_and_connect_stream_or_die(host, port);
+       xmove_fd(create_and_connect_stream_or_die(host, port), netfd);
 
-       setsockopt(G.netfd, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
+       setsockopt(netfd, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
 
-       signal(SIGINT, fgotsig);
+       signal(SIGINT, record_signo);
 
 #ifdef USE_POLL
-       ufds[0].fd = 0; ufds[1].fd = G.netfd;
+       ufds[0].fd = 0; ufds[1].fd = netfd;
        ufds[0].events = ufds[1].events = POLLIN;
 #else
        FD_ZERO(&readfds);
        FD_SET(STDIN_FILENO, &readfds);
-       FD_SET(G.netfd, &readfds);
-       maxfd = G.netfd + 1;
+       FD_SET(netfd, &readfds);
+       maxfd = netfd + 1;
 #endif
 
        while (1) {
@@ -619,8 +610,8 @@ int telnet_main(int argc, char **argv)
                        /* timeout */
                case -1:
                        /* error, ignore and/or log something, bay go to loop */
-                       if (G.gotsig)
-                               conescape();
+                       if (bb_got_signal)
+                               con_escape();
                        else
                                sleep(1);
                        break;
@@ -636,23 +627,23 @@ int telnet_main(int argc, char **argv)
                                if (len <= 0)
                                        doexit(EXIT_SUCCESS);
                                TRACE(0, ("Read con: %d\n", len));
-                               handlenetoutput(len);
+                               handle_net_output(len);
                        }
 
 #ifdef USE_POLL
                        if (ufds[1].revents) /* well, should check POLLIN, but ... */
 #else
-                       if (FD_ISSET(G.netfd, &rfds))
+                       if (FD_ISSET(netfd, &rfds))
 #endif
                        {
-                               len = read(G.netfd, G.buf, DATABUFSIZE);
+                               len = read(netfd, G.buf, DATABUFSIZE);
                                if (len <= 0) {
                                        write_str(1, "Connection closed by foreign host\r\n");
                                        doexit(EXIT_FAILURE);
                                }
-                               TRACE(0, ("Read netfd (%d): %d\n", G.netfd, len));
-                               handlenetinput(len);
+                               TRACE(0, ("Read netfd (%d): %d\n", netfd, len));
+                               handle_net_input(len);
                        }
                }
-       }
+       } /* while (1) */
 }