telnet: someone tried to do data optimization before me. Complete it.

   text    data     bss     dec     hex filename
   2558       0     404    2962     b92 busybox.t2/networking/telnet.o
   2542       0       0    2542     9ee busybox.t3/networking/telnet.o

1 files changed, 83 insertions, 96 deletions

diff --git a/networking/telnet.c b/networking/telnet.c
index 134157273..82dbb588d 100644
--- a/networking/telnet.c
+++ b/networking/telnet.c
@@ -32,10 +32,10 @@
 #define TRACE(x, y)
 #endif
 
-#define DATABUFSIZE  128
-#define IACBUFSIZE   128
-
 enum {
+	DATABUFSIZE = 128,
+	IACBUFSIZE  = 128,
+
 	CHM_TRY = 0,
 	CHM_ON = 1,
 	CHM_OFF = 2,
@@ -50,40 +50,36 @@ enum {
 	TS_SUB2 = 5,
 };
 
-#define WriteCS(fd, str) write(fd, str, sizeof str -1)
-
 typedef unsigned char byte;
 
-/* use globals to reduce size ??? */ /* test this hypothesis later */
-static struct Globalvars {
-	int		netfd; /* console fd:s are 0 and 1 (and 2) */
-    /* same buffer used both for network and console read/write */
-	char    buf[DATABUFSIZE]; /* allocating so static size is smaller */
+
+struct globals {
+	int	netfd; /* console fd:s are 0 and 1 (and 2) */
+	short	iaclen; /* could even use byte */
 	byte	telstate; /* telnet negotiation state from network input */
 	byte	telwish;  /* DO, DONT, WILL, WONT */
 	byte    charmode;
 	byte    telflags;
 	byte	gotsig;
 	byte	do_termios;
-	/* buffer to handle telnet negotiations */
+#if ENABLE_FEATURE_TELNET_TTYPE
+	char	*ttype;
+#endif
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+	const char *autologin;
+#endif
+#if ENABLE_FEATURE_AUTOWIDTH
+	int	win_width, win_height;
+#endif
+	/* same buffer used both for network and console read/write */
+	char    buf[DATABUFSIZE]; /* allocating so static size is smaller */
 	char    iacbuf[IACBUFSIZE];
-	short	iaclen; /* could even use byte */
 	struct termios termios_def;
 	struct termios termios_raw;
-} G;
-
-#define xUSE_GLOBALVAR_PTR /* xUSE... -> don't use :D (makes smaller code) */
+};
 
-#ifdef USE_GLOBALVAR_PTR
-struct Globalvars * Gptr;
-#define G (*Gptr)
-#endif
+#define G (*(struct globals*)bb_common_bufsiz1)
 
-static void iacflush(void)
-{
-	write(G.netfd, G.iacbuf, G.iaclen);
-	G.iaclen = 0;
-}
 
 /* Function prototypes */
 static void rawmode(void);
@@ -93,20 +89,16 @@ static void will_charmode(void);
 static void telopt(byte c);
 static int subneg(byte c);
 
-/* Some globals */
-#ifdef CONFIG_FEATURE_TELNET_TTYPE
-static char *ttype;
-#endif
-
-#ifdef CONFIG_FEATURE_TELNET_AUTOLOGIN
-static const char *autologin;
-#endif
+static void iacflush(void)
+{
+	write(G.netfd, G.iacbuf, G.iaclen);
+	G.iaclen = 0;
+}
 
-#ifdef CONFIG_FEATURE_AUTOWIDTH
-static int win_width, win_height;
-#endif
+#define write_str(fd, str) write(fd, str, sizeof(str) - 1)
 
-static void doexit(int ev)
+static void	/* buffer to handle telnet negotiations */
+doexit(int ev)
 {
 	cookmode();
 	exit(ev);
@@ -119,7 +111,7 @@ static void conescape(void)
 	if (G.gotsig)	/* came from line  mode... go raw */
 		rawmode();
 
-	WriteCS(1, "\r\nConsole escape. Commands are:\r\n\n"
+	write_str(1, "\r\nConsole escape. Commands are:\r\n\n"
 			" l	go to line mode\r\n"
 			" c	go to character mode\r\n"
 			" z	suspend telnet\r\n"
@@ -128,18 +120,15 @@ static void conescape(void)
 	if (read(0, &b, 1) <= 0)
 		doexit(1);
 
-	switch (b)
-	{
+	switch (b) {
 	case 'l':
-		if (!G.gotsig)
-		{
+		if (!G.gotsig) {
 			do_linemode();
 			goto rrturn;
 		}
 		break;
 	case 'c':
-		if (G.gotsig)
-		{
+		if (G.gotsig) {
 			will_charmode();
 			goto rrturn;
 		}
@@ -153,7 +142,7 @@ static void conescape(void)
 		doexit(0);
 	}
 
-	WriteCS(1, "continuing...\r\n");
+	write_str(1, "continuing...\r\n");
 
 	if (G.gotsig)
 		cookmode();
@@ -296,7 +285,7 @@ static void putiac2(byte wwdd, byte c)
 	putiac(c);
 }
 
-#ifdef CONFIG_FEATURE_TELNET_TTYPE
+#if ENABLE_FEATURE_TELNET_TTYPE
 static void putiac_subopt(byte c, char *str)
 {
 	int	len = strlen(str) + 6;   // ( 2 + 1 + 1 + strlen + 2 )
@@ -317,10 +306,10 @@ static void putiac_subopt(byte c, char *str)
 }
 #endif
 
-#ifdef CONFIG_FEATURE_TELNET_AUTOLOGIN
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
 static void putiac_subopt_autologin(void)
 {
-	int len = strlen(autologin) + 6;	// (2 + 1 + 1 + strlen + 2)
+	int len = strlen(G.autologin) + 6;	// (2 + 1 + 1 + strlen + 2)
 	const char *user = "USER";
 
 	if (G.iaclen + len > IACBUFSIZE)
@@ -337,15 +326,15 @@ static void putiac_subopt_autologin(void)
 
 	putiac(NEW_ENV_VALUE);
 
-	while (*autologin)
-		putiac(*autologin++);
+	while (*G.autologin)
+		putiac(*G.autologin++);
 
 	putiac(IAC);
 	putiac(SE);
 }
 #endif
 
-#ifdef CONFIG_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_AUTOWIDTH
 static void putiac_naws(byte c, int x, int y)
 {
 	if (G.iaclen + 9 > IACBUFSIZE)
@@ -419,24 +408,27 @@ static void do_linemode(void)
 
 static void to_notsup(char c)
 {
-	if      (G.telwish == WILL)	putiac2(DONT, c);
-	else if (G.telwish == DO)	putiac2(WONT, c);
+	if (G.telwish == WILL)
+		putiac2(DONT, c);
+	else if (G.telwish == DO)
+		putiac2(WONT, c);
 }
 
 static void to_echo(void)
 {
 	/* if server requests ECHO, don't agree */
-	if      (G.telwish == DO) {	putiac2(WONT, TELOPT_ECHO);	return; }
-	else if (G.telwish == DONT)	return;
+	if (G.telwish == DO) {
+		putiac2(WONT, TELOPT_ECHO);
+		return;
+	}
+	if (G.telwish == DONT)
+		return;
 
-	if (G.telflags & UF_ECHO)
-	{
+	if (G.telflags & UF_ECHO) {
 		if (G.telwish == WILL)
 			return;
-	}
-	else
-		if (G.telwish == WONT)
-			return;
+	} else if (G.telwish == WONT)
+		return;
 
 	if (G.charmode != CHM_OFF)
 		G.telflags ^= UF_ECHO;
@@ -447,21 +439,18 @@ static void to_echo(void)
 		putiac2(DONT, TELOPT_ECHO);
 
 	setConMode();
-	WriteCS(1, "\r\n");  /* sudden modec */
+	write_str(1, "\r\n");  /* sudden modec */
 }
 
 static void to_sga(void)
 {
 	/* daemon always sends will/wont, client do/dont */
 
-	if (G.telflags & UF_SGA)
-	{
+	if (G.telflags & UF_SGA) {
 		if (G.telwish == WILL)
 			return;
-	}
-	else
-		if (G.telwish == WONT)
-			return;
+	} else if (G.telwish == WONT)
+		return;
 
 	if ((G.telflags ^= UF_SGA) & UF_SGA) /* toggle */
 		putiac2(DO, TELOPT_SGA);
@@ -469,31 +458,31 @@ static void to_sga(void)
 		putiac2(DONT, TELOPT_SGA);
 }
 
-#ifdef CONFIG_FEATURE_TELNET_TTYPE
+#if ENABLE_FEATURE_TELNET_TTYPE
 static void to_ttype(void)
 {
 	/* Tell server we will (or won't) do TTYPE */
 
-	if(ttype)
+	if (G.ttype)
 		putiac2(WILL, TELOPT_TTYPE);
 	else
 		putiac2(WONT, TELOPT_TTYPE);
 }
 #endif
 
-#ifdef CONFIG_FEATURE_TELNET_AUTOLOGIN
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
 static void to_new_environ(void)
 {
 	/* Tell server we will (or will not) do AUTOLOGIN */
 
-	if (autologin)
+	if (G.autologin)
 		putiac2(WILL, TELOPT_NEW_ENVIRON);
 	else
 		putiac2(WONT, TELOPT_NEW_ENVIRON);
 }
 #endif
 
-#ifdef CONFIG_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_AUTOWIDTH
 static void to_naws(void)
 {
 	/* Tell server we will do NAWS */
@@ -508,18 +497,18 @@ static void telopt(byte c)
 		to_echo(); break;
 	case TELOPT_SGA:
 		to_sga(); break;
-#ifdef CONFIG_FEATURE_TELNET_TTYPE
+#if ENABLE_FEATURE_TELNET_TTYPE
 	case TELOPT_TTYPE:
 		to_ttype(); break;
 #endif
-#ifdef CONFIG_FEATURE_TELNET_AUTOLOGIN
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
 	case TELOPT_NEW_ENVIRON:
 		to_new_environ(); break;
 #endif
-#ifdef CONFIG_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_AUTOWIDTH
 	case TELOPT_NAWS:
 		to_naws();
-		putiac_naws(c, win_width, win_height);
+		putiac_naws(c, G.win_width, G.win_height);
 		break;
 #endif
 	default:
@@ -535,17 +524,16 @@ static void telopt(byte c)
 
 static int subneg(byte c)
 {
-	switch (G.telstate)
-	{
+	switch (G.telstate) {
 	case TS_SUB1:
 		if (c == IAC)
 			G.telstate = TS_SUB2;
-#ifdef CONFIG_FEATURE_TELNET_TTYPE
+#if ENABLE_FEATURE_TELNET_TTYPE
 		else
 		if (c == TELOPT_TTYPE)
-			putiac_subopt(TELOPT_TTYPE,ttype);
+			putiac_subopt(TELOPT_TTYPE, G.ttype);
 #endif
-#ifdef CONFIG_FEATURE_TELNET_AUTOLOGIN
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
 		else
 		if (c == TELOPT_NEW_ENVIRON)
 			putiac_subopt_autologin();
@@ -578,6 +566,8 @@ static void cookmode(void)
 	if (G.do_termios) tcsetattr(0, TCSADRAIN, &G.termios_def);
 }
 
+void BUG_telnet_globals_too_big(void);
+
 int telnet_main(int argc, char** argv);
 int telnet_main(int argc, char** argv)
 {
@@ -591,15 +581,17 @@ int telnet_main(int argc, char** argv)
 	int maxfd;
 #endif
 
-#ifdef CONFIG_FEATURE_AUTOWIDTH
-	get_terminal_width_height(0, &win_width, &win_height);
-#endif
+	if (sizeof(G) > sizeof(bb_common_bufsiz1))
+		BUG_telnet_globals_too_big();
+	/* memset(&G, 0, sizeof G); - already is */
 
-#ifdef CONFIG_FEATURE_TELNET_TTYPE
-	ttype = getenv("TERM");
+#if ENABLE_FEATURE_AUTOWIDTH
+	get_terminal_width_height(0, &G.win_width, &G.win_height);
 #endif
 
-	/* memset(&G, 0, sizeof G); - already is */
+#if ENABLE_FEATURE_TELNET_TTYPE
+	G.ttype = getenv("TERM");
+#endif
 
 	if (tcgetattr(0, &G.termios_def) >= 0) {
 		G.do_termios = 1;
@@ -610,9 +602,9 @@ int telnet_main(int argc, char** argv)
 	if (argc < 2)
 		bb_show_usage();
 
-#ifdef CONFIG_FEATURE_TELNET_AUTOLOGIN
-	if (1 & getopt32(argc, argv, "al:", &autologin))
-		autologin = getenv("USER");
+#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+	if (1 & getopt32(argc, argv, "al:", &G.autologin))
+		G.autologin = getenv("USER");
 	argv += optind;
 #else
 	argv++;
@@ -667,12 +659,9 @@ int telnet_main(int argc, char** argv)
 #endif
 			{
 				len = read(0, G.buf, DATABUFSIZE);
-
 				if (len <= 0)
 					doexit(0);
-
 				TRACE(0, ("Read con: %d\n", len));
-
 				handlenetoutput(len);
 			}
 
@@ -683,13 +672,11 @@ int telnet_main(int argc, char** argv)
 #endif
 			{
 				len = read(G.netfd, G.buf, DATABUFSIZE);
-
 				if (len <= 0) {
-					WriteCS(1, "Connection closed by foreign host.\r\n");
+					write_str(1, "Connection closed by foreign host\r\n");
 					doexit(1);
 				}
 				TRACE(0, ("Read netfd (%d): %d\n", G.netfd, len));
-
 				handlenetinput(len);
 			}
 		}