0ac0492b3
Denys Vlasenko
2026-02-23
Subject
telnet: code shrink
Binary
No binary (build failed)
Architecture & Compiler Flags
gcc -Wp,-MD,applets/.usage.d -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -Iinclude -Iinclude -o applets/usage applets/usage.c
Build Log
(log yok)
Commit Diff GitHub →
networking/telnet.c+25 -21
| @@ -103,9 +103,6 @@ static char *bin_to_hex(const void *hash_value, unsigned hash_length) | |
| #endif | |
| enum { | |
| - | BUFSIZE = 1024, |
| - | BUFMASK = BUFSIZE - 1, |
| - | |
| TS_NORMAL = 0, | |
| TS_IAC = 1, | |
| TS_OPT = 2, | |
| @@ -114,31 +111,24 @@ enum { | |
| TS_CR = 5, | |
| MAX_NAWS_SIZE = 13, /* pathological 65535x65535 case needs full escaping */ | |
| + | |
| + | netfd = 3, |
| }; | |
| typedef unsigned char byte; | |
| - | enum { netfd = 3 }; |
| - | |
| typedef struct stdin_to_net { | |
| STRUCT_CONNECTION | |
| int rdidx, wridx, size; | |
| - | byte buf[BUFSIZE]; |
| + | //byte buf[BUFSIZE]; |
| } stdin_to_net_t; | |
| - | |
| typedef struct net_to_stdout { | |
| STRUCT_CONNECTION | |
| int rdidx, wridx, size; | |
| byte input_state; | |
| byte negotiation_verb; | |
| - | byte buf[BUFSIZE]; |
| + | //byte buf[BUFSIZE]; |
| } net_to_stdout_t; | |
| - | |
| - | static int remaining_free_bytes(int n) |
| - | { |
| - | return BUFSIZE - n; |
| - | } |
| - | |
| #if DEBUG | |
| static void set_input_state(net_to_stdout_t *conn, int new_state, int c) | |
| { | |
| @@ -155,7 +145,9 @@ static void set_input_state(net_to_stdout_t *conn, int new_state, int c) | |
| struct globals { | |
| unsigned flags; | |
| + | /* Set when server agreed to use NAWS: */ |
| #define FLAGS_NAWS_ON (1 << 0) | |
| + | /* SGA option seen and responded to, no longer look for it: */ |
| #define FLAGS_SGA_SEEN (1 << 1) | |
| /* Seen telnet protocol from server and sent our wishes: */ | |
| #define INITIAL_SENT (1 << 2) | |
| @@ -183,12 +175,24 @@ struct globals { | |
| net_to_stdout_t conn_net2stdout; | |
| struct termios termios_def; | |
| struct termios termios_raw; | |
| + | // buf[] arrays in conn structs are conceptually cleaner, but they |
| + | // make G.member offsets larger -> larger code |
| + | #define BUF_TTY2NET ((byte*)bb_common_bufsiz1) |
| + | #define BUF_NET2TTY G.buf2 |
| + | #define BUFSIZE 1024 |
| + | /* Note: can't just increase BUFSIZE arbitrarily: common bufsiz1 is not guaranteed to be >1k! */ |
| + | #define BUFMASK (BUFSIZE - 1) |
| + | byte buf2[BUFSIZE]; |
| } FIX_ALIASING; | |
| #define G (*ptr_to_globals) | |
| #define INIT_G() do { \ | |
| SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ | |
| } while (0) | |
| + | static int remaining_free_bytes(int n) |
| + | { |
| + | return BUFSIZE - n; |
| + | } |
| #if ENABLE_FEATURE_TELNET_WIDTH | |
| static void handle_SIGWINCH(int sig UNUSED_PARAM) | |
| @@ -221,7 +225,7 @@ static void put_iac(int c) | |
| { | |
| stdin_to_net_t *conn = &G.conn_stdin2net; | |
| /* Write directly to stdin2net buffer */ | |
| - | conn->buf[conn->rdidx] = c; /* "... & 0xff" is implicit */ |
| + | BUF_TTY2NET[conn->rdidx] = c; /* "... & 0xff" is implicit */ |
| conn->rdidx = (conn->rdidx + 1) & BUFMASK; | |
| conn->size++; | |
| } | |
| @@ -528,7 +532,7 @@ static int read_from_stdin(void *this) | |
| if (count == 0) | |
| return 0; | |
| - | start = conn->buf + conn->rdidx; |
| + | start = BUF_TTY2NET + conn->rdidx; |
| count = safe_read(conn->read_fd, start, count); | |
| if (count <= 0) { | |
| conn->read_fd = -1; | |
| @@ -606,7 +610,7 @@ static int write_to_net(void *this) | |
| handle_changes_in_options(conn); /* yes */ | |
| count = MIN(BUFSIZE - conn->wridx, conn->size); | |
| - | count = safe_write(conn->write_fd, conn->buf + conn->wridx, count); |
| + | count = safe_write(conn->write_fd, BUF_TTY2NET + conn->wridx, count); |
| if (count <= 0) { | |
| if (count < 0 && errno == EAGAIN) | |
| return 0; | |
| @@ -647,7 +651,7 @@ static int read_from_net(void *this) | |
| count = MIN(BUFSIZE - conn->rdidx, count); /* can't be zero */ | |
| /* Read directly into circular buffer's linear fragment */ | |
| - | dst = conn->buf + conn->rdidx; |
| + | dst = BUF_NET2TTY + conn->rdidx; |
| count = safe_read(conn->read_fd, dst, count); | |
| dbg("read_from_net bytes:%d input_state:%d %s", | |
| count, conn->input_state, bin_to_hex(dst, count > 0 ? count : 0)); | |
| @@ -804,7 +808,7 @@ static int read_from_net(void *this) | |
| } | |
| /* Update circular buffer: only the compacted data */ | |
| - | count = dst - (conn->buf + conn->rdidx); |
| + | count = dst - (BUF_NET2TTY + conn->rdidx); |
| conn->size += count; | |
| conn->rdidx = (conn->rdidx + count) & BUFMASK; | |
| @@ -831,8 +835,8 @@ static int write_to_stdout(void *this) | |
| int wr = MIN(BUFSIZE - conn->wridx, conn->size); | |
| ssize_t count; | |
| - | dbg("write_to_stdout: wr:%d %s", wr, bin_to_hex(conn->buf + conn->wridx, wr)); |
| - | count = safe_write(conn->write_fd, conn->buf + conn->wridx, wr); |
| + | dbg("write_to_stdout: wr:%d %s", wr, bin_to_hex(BUF_NET2TTY + conn->wridx, wr)); |
| + | count = safe_write(conn->write_fd, BUF_NET2TTY + conn->wridx, wr); |
| if (count <= 0) { | |
| if (count < 0 && errno == EAGAIN) | |
| return 0; | |