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telnet: code shrink

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function                                             old     new   delta
put_iac3_IAC_x_y_merged                                -      21     +21
put_iac4_msb_lsb                                       -      19     +19
put_iac2_msb_lsb                                       -      19     +19
put_iac                                               20      34     +14
iac_flush                                             32      36      +4
put_iac2_merged                                       46       -     -46
telnet_main                                         1492    1270    -222
------------------------------------------------------------------------------
(add/remove: 3/1 grow/shrink: 2/1 up/down: 77/-268)          Total: -191 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2019-01-06 18:45:38 +01:00
parent 5bfc4a32fd
commit 935afafcf3
1 changed files with 57 additions and 70 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

127
networking/telnet.c
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@ -152,8 +152,10 @@ static void subneg(byte c);
static void iac_flush(void)
{
full_write(netfd, G.iacbuf, G.iaclen);
G.iaclen = 0;
if (G.iaclen != 0) {
full_write(netfd, G.iacbuf, G.iaclen);
G.iaclen = 0;
}
}
static void doexit(int ev) NORETURN;
@ -338,88 +340,73 @@ static void handle_net_input(int len)
static void put_iac(int c)
{
G.iacbuf[G.iaclen++] = c;
}
static void put_iac2_merged(unsigned wwdd_and_c)
{
if (G.iaclen + 3 > IACBUFSIZE)
int iaclen = G.iaclen;
if (iaclen >= IACBUFSIZE) {
iac_flush();
put_iac(IAC);
put_iac(wwdd_and_c >> 8);
put_iac(wwdd_and_c & 0xff);
iaclen = 0;
}
G.iacbuf[iaclen] = c; /* "... & 0xff" is implicit */
G.iaclen = iaclen + 1;
}
#define put_iac2(wwdd,c) put_iac2_merged(((wwdd)<<8) + (c))
static void put_iac2_msb_lsb(unsigned x_y)
{
put_iac(x_y >> 8); /* "... & 0xff" is implicit */
put_iac(x_y); /* "... & 0xff" is implicit */
}
#define put_iac2_x_y(x,y) put_iac2_msb_lsb(((x)<<8) + (y))
static void put_iac4_msb_lsb(unsigned x_y_z_t)
{
put_iac2_msb_lsb(x_y_z_t >> 16);
put_iac2_msb_lsb(x_y_z_t); /* "... & 0xffff" is implicit */
}
#define put_iac4_x_y_z_t(x,y,z,t) put_iac4_msb_lsb(((x)<<24) + ((y)<<16) + ((z)<<8) + (t))
static void put_iac3_IAC_x_y_merged(unsigned wwdd_and_c)
{
put_iac(IAC);
put_iac2_msb_lsb(wwdd_and_c);
}
#define put_iac3_IAC_x_y(wwdd,c) put_iac3_IAC_x_y_merged(((wwdd)<<8) + (c))
#if ENABLE_FEATURE_TELNET_TTYPE
static void put_iac_subopt(byte c, char *str)
{
int len = strlen(str) + 6; // ( 2 + 1 + 1 + strlen + 2 )
if (G.iaclen + len > IACBUFSIZE)
iac_flush();
put_iac(IAC);
put_iac(SB);
put_iac(c);
put_iac(0);
put_iac4_x_y_z_t(IAC, SB, c, 0);
while (*str)
put_iac(*str++);
put_iac(IAC);
put_iac(SE);
put_iac2_x_y(IAC, SE);
}
#endif
#if ENABLE_FEATURE_TELNET_AUTOLOGIN
static void put_iac_subopt_autologin(void)
{
int len = strlen(G.autologin) + 6; // (2 + 1 + 1 + strlen + 2)
const char *p = "USER";
const char *p;
if (G.iaclen + len > IACBUFSIZE)
iac_flush();
put_iac(IAC);
put_iac(SB);
put_iac(TELOPT_NEW_ENVIRON);
put_iac(TELQUAL_IS);
put_iac(NEW_ENV_VAR);
while (*p)
put_iac(*p++);
put_iac(NEW_ENV_VALUE);
put_iac4_x_y_z_t(IAC, SB, TELOPT_NEW_ENVIRON, TELQUAL_IS);
put_iac4_x_y_z_t(NEW_ENV_VAR, 'U', 'S', 'E'); /* "USER" */
put_iac2_x_y('R', NEW_ENV_VALUE);
p = G.autologin;
while (*p)
put_iac(*p++);
put_iac(IAC);
put_iac(SE);
put_iac2_x_y(IAC, SE);
}
#endif
#if ENABLE_FEATURE_TELNET_WIDTH
static void put_iac_naws(byte c, int x, int y)
{
if (G.iaclen + 9 > IACBUFSIZE)
iac_flush();
put_iac3_IAC_x_y(SB, c);
put_iac(IAC);
put_iac(SB);
put_iac(c);
put_iac4_msb_lsb((x << 16) + y);
/* "... & 0xff" implicitly done below */
put_iac(x >> 8);
put_iac(x);
put_iac(y >> 8);
put_iac(y);
put_iac(IAC);
put_iac(SE);
put_iac2_x_y(IAC, SE);
}
#endif
@ -448,8 +435,8 @@ static void will_charmode(void)
G.telflags |= (UF_ECHO | UF_SGA);
setConMode();
put_iac2(DO, TELOPT_ECHO);
put_iac2(DO, TELOPT_SGA);
put_iac3_IAC_x_y(DO, TELOPT_ECHO);
put_iac3_IAC_x_y(DO, TELOPT_SGA);
iac_flush();
}
@ -459,24 +446,24 @@ static void do_linemode(void)
G.telflags &= ~(UF_ECHO | UF_SGA);
setConMode();
put_iac2(DONT, TELOPT_ECHO);
put_iac2(DONT, TELOPT_SGA);
put_iac3_IAC_x_y(DONT, TELOPT_ECHO);
put_iac3_IAC_x_y(DONT, TELOPT_SGA);
iac_flush();
}
static void to_notsup(char c)
{
if (G.telwish == WILL)
put_iac2(DONT, c);
put_iac3_IAC_x_y(DONT, c);
else if (G.telwish == DO)
put_iac2(WONT, c);
put_iac3_IAC_x_y(WONT, c);
}
static void to_echo(void)
{
/* if server requests ECHO, don't agree */
if (G.telwish == DO) {
put_iac2(WONT, TELOPT_ECHO);
put_iac3_IAC_x_y(WONT, TELOPT_ECHO);
return;
}
if (G.telwish == DONT)
@ -492,9 +479,9 @@ static void to_echo(void)
G.telflags ^= UF_ECHO;
if (G.telflags & UF_ECHO)
put_iac2(DO, TELOPT_ECHO);
put_iac3_IAC_x_y(DO, TELOPT_ECHO);
else
put_iac2(DONT, TELOPT_ECHO);
put_iac3_IAC_x_y(DONT, TELOPT_ECHO);
setConMode();
full_write1_str("\r\n"); /* sudden modec */
@ -512,9 +499,9 @@ static void to_sga(void)
G.telflags ^= UF_SGA; /* toggle */
if (G.telflags & UF_SGA)
put_iac2(DO, TELOPT_SGA);
put_iac3_IAC_x_y(DO, TELOPT_SGA);
else
put_iac2(DONT, TELOPT_SGA);
put_iac3_IAC_x_y(DONT, TELOPT_SGA);
}
#if ENABLE_FEATURE_TELNET_TTYPE
@ -522,9 +509,9 @@ static void to_ttype(void)
{
/* Tell server we will (or won't) do TTYPE */
if (G.ttype)
put_iac2(WILL, TELOPT_TTYPE);
put_iac3_IAC_x_y(WILL, TELOPT_TTYPE);
else
put_iac2(WONT, TELOPT_TTYPE);
put_iac3_IAC_x_y(WONT, TELOPT_TTYPE);
}
#endif
@ -533,9 +520,9 @@ static void to_new_environ(void)
{
/* Tell server we will (or will not) do AUTOLOGIN */
if (G.autologin)
put_iac2(WILL, TELOPT_NEW_ENVIRON);
put_iac3_IAC_x_y(WILL, TELOPT_NEW_ENVIRON);
else
put_iac2(WONT, TELOPT_NEW_ENVIRON);
put_iac3_IAC_x_y(WONT, TELOPT_NEW_ENVIRON);
}
#endif
@ -543,7 +530,7 @@ static void to_new_environ(void)
static void to_naws(void)
{
/* Tell server we will do NAWS */
put_iac2(WILL, TELOPT_NAWS);
put_iac3_IAC_x_y(WILL, TELOPT_NAWS);
}
#endif