nc: remove a bit of bloat

inetd: more NOMMU fixes
rx: shrink
devfsd: minor shrink
vlock: shrink
tcpudp: narrow down window where we have no wildcard socket

parse_one_line                                      1015    1102     +87
init_ring                                              -      53     +53
xzalloc_lsa                                            -      48     +48
read_byte                                             51      50      -1
rearm_alarm                                           28      25      -3
nc_main                                             1028    1000     -28
initring                                              53       -     -53
vlock_main                                           583     496     -87
reread_config_file                                  1089     991     -98
rx_main                                             1046     912    -134
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 1/6 up/down: 188/-404)         Total: -216 bytes
   text    data     bss     dec     hex filename
 800120     661    7428  808209   c5511 busybox_old
 799796     661    7428  807885   c53cd busybox_unstripped

2 files changed, 103 insertions, 138 deletions

diff --git a/miscutils/devfsd.c b/miscutils/devfsd.c
index 286f00fd8..50c8203cb 100644
--- a/miscutils/devfsd.c
+++ b/miscutils/devfsd.c
@@ -386,15 +386,14 @@ int devfsd_main(int argc, char **argv)
         /*  Tell kernel we are special(i.e. we get to see hidden entries)  */
         xioctl(fd, DEVFSDIOC_SET_EVENT_MASK, 0);
 
+        /*  Set up SIGHUP and SIGUSR1 handlers  */
         sigemptyset(&new_action.sa_mask);
         new_action.sa_flags = 0;
-
-        /*  Set up SIGHUP and SIGUSR1 handlers  */
         new_action.sa_handler = signal_handler;
-        if (sigaction(SIGHUP, &new_action, NULL) != 0 || sigaction(SIGUSR1, &new_action, NULL) != 0)
-                bb_error_msg_and_die("sigaction");
+        sigaction(SIGHUP, &new_action, NULL);
+        sigaction(SIGUSR1, &new_action, NULL);
 
-        printf("%s v%s  started for %s\n",applet_name, DEVFSD_VERSION, mount_point);
+        printf("%s v%s started for %s\n", applet_name, DEVFSD_VERSION, mount_point);
 
         /*  Set umask so that mknod(2), open(2) and mkdir(2) have complete control over permissions  */
         umask(0);
diff --git a/miscutils/rx.c b/miscutils/rx.c
index 8ccea4974..9a8fcaa20 100644
--- a/miscutils/rx.c
+++ b/miscutils/rx.c
@@ -16,7 +16,6 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  *
  * This was originally written for blob and then adapted for busybox.
- *
  */
 
 #include "libbb.h"
@@ -29,66 +28,59 @@
 #define BS  0x08
 
 /*
-
 Cf:
-
   http://www.textfiles.com/apple/xmodem
   http://www.phys.washington.edu/~belonis/xmodem/docxmodem.txt
   http://www.phys.washington.edu/~belonis/xmodem/docymodem.txt
   http://www.phys.washington.edu/~belonis/xmodem/modmprot.col
-
 */
 
 #define TIMEOUT 1
 #define TIMEOUT_LONG 10
 #define MAXERRORS 10
 
-static int read_byte(int fd, unsigned timeout)
+#define read_fd  STDIN_FILENO
+#define write_fd STDOUT_FILENO
+
+static int read_byte(unsigned timeout)
 {
         char buf[1];
         int n;
 
         alarm(timeout);
-
-        n = read(fd, &buf, 1);
-
+        /* NOT safe_read! We want ALRM to interrupt us */
+        n = read(read_fd, buf, 1);
         alarm(0);
-
         if (n == 1)
-                return buf[0] & 0xff;
-        else
-                return -1;
+                return (unsigned char)buf[0];
+        return -1;
 }
 
-static int receive(char *error_buf, size_t error_buf_size,
-                                   int ttyfd, int filefd)
+static int receive(/*int read_fd, */int file_fd)
 {
-        char blockBuf[1024];
-        unsigned int errors = 0;
-        unsigned int wantBlockNo = 1;
-        unsigned int length = 0;
-        int docrc = 1;
+        unsigned char blockBuf[1024];
+        unsigned errors = 0;
+        unsigned wantBlockNo = 1;
+        unsigned length = 0;
+        int do_crc = 1;
         char nak = 'C';
-        unsigned int timeout = TIMEOUT_LONG;
-
-#define note_error(fmt,args...) \
-        snprintf(error_buf, error_buf_size, fmt,##args)
+        unsigned timeout = TIMEOUT_LONG;
 
         /* Flush pending input */
-        tcflush(ttyfd, TCIFLUSH);
+        tcflush(read_fd, TCIFLUSH);
 
         /* Ask for CRC; if we get errors, we will go with checksum */
-        write(ttyfd, &nak, 1);
+        full_write(write_fd, &nak, 1);
 
         for (;;) {
                 int blockBegin;
                 int blockNo, blockNoOnesCompl;
                 int blockLength;
-                int cksum = 0;
-                int crcHi = 0;
-                int crcLo = 0;
+                int cksum_crc;  /* cksum OR crc */
+                int expected;
+                int i,j;
 
-                blockBegin = read_byte(ttyfd, timeout);
+                blockBegin = read_byte(timeout);
                 if (blockBegin < 0)
                         goto timeout;
 
@@ -102,52 +94,47 @@ static int receive(char *error_buf, size_t error_buf_size,
 
                 case EOT:
                         nak = ACK;
-                        write(ttyfd, &nak, 1);
-                        goto done;
+                        full_write(write_fd, &nak, 1);
+                        return length;
 
                 default:
                         goto error;
                 }
 
                 /* block no */
-                blockNo = read_byte(ttyfd, TIMEOUT);
+                blockNo = read_byte(TIMEOUT);
                 if (blockNo < 0)
                         goto timeout;
 
                 /* block no one's compliment */
-                blockNoOnesCompl = read_byte(ttyfd, TIMEOUT);
+                blockNoOnesCompl = read_byte(TIMEOUT);
                 if (blockNoOnesCompl < 0)
                         goto timeout;
 
                 if (blockNo != (255 - blockNoOnesCompl)) {
-                        note_error("bad block ones compl");
+                        bb_error_msg("bad block ones compl");
                         goto error;
                 }
 
                 blockLength = (blockBegin == SOH) ? 128 : 1024;
 
-                {
-                        int i;
-
-                        for (i = 0; i < blockLength; i++) {
-                                int cc = read_byte(ttyfd, TIMEOUT);
-                                if (cc < 0)
-                                        goto timeout;
-                                blockBuf[i] = cc;
-                        }
+                for (i = 0; i < blockLength; i++) {
+                        int cc = read_byte(TIMEOUT);
+                        if (cc < 0)
+                                goto timeout;
+                        blockBuf[i] = cc;
                 }
 
-                if (docrc) {
-                        crcHi = read_byte(ttyfd, TIMEOUT);
-                        if (crcHi < 0)
+                if (do_crc) {
+                        cksum_crc = read_byte(TIMEOUT);
+                        if (cksum_crc < 0)
                                 goto timeout;
-
-                        crcLo = read_byte(ttyfd, TIMEOUT);
-                        if (crcLo < 0)
+                        cksum_crc = (cksum_crc << 8) | read_byte(TIMEOUT);
+                        if (cksum_crc < 0)
                                 goto timeout;
                 } else {
-                        cksum = read_byte(ttyfd, TIMEOUT);
-                        if (cksum < 0)
+                        cksum_crc = read_byte(TIMEOUT);
+                        if (cksum_crc < 0)
                                 goto timeout;
                 }
 
@@ -156,93 +143,74 @@ static int receive(char *error_buf, size_t error_buf_size,
                         /* this also ignores the initial block 0 which is */
                         /* meta data. */
                         goto next;
-                } else if (blockNo != (wantBlockNo & 0xff)) {
-                        note_error("unexpected block no, 0x%08x, expecting 0x%08x", blockNo, wantBlockNo);
+                }
+                if (blockNo != (wantBlockNo & 0xff)) {
+                        bb_error_msg("unexpected block no, 0x%08x, expecting 0x%08x", blockNo, wantBlockNo);
                         goto error;
                 }
 
-                if (docrc) {
-                        int crc = 0;
-                        int i, j;
-                        int expectedCrcHi;
-                        int expectedCrcLo;
-
+                expected = 0;
+                if (do_crc) {
                         for (i = 0; i < blockLength; i++) {
-                                crc = crc ^ (int) blockBuf[i] << 8;
-                                for (j = 0; j < 8; j++)
-                                        if (crc & 0x8000)
-                                                crc = crc << 1 ^ 0x1021;
+                                expected = expected ^ blockBuf[i] << 8;
+                                for (j = 0; j < 8; j++) {
+                                        if (expected & 0x8000)
+                                                expected = expected << 1 ^ 0x1021;
                                         else
-                                                crc = crc << 1;
-                        }
-
-                        expectedCrcHi = (crc >> 8) & 0xff;
-                        expectedCrcLo = crc & 0xff;
-
-                        if ((crcHi != expectedCrcHi) ||
-                            (crcLo != expectedCrcLo)) {
-                                note_error("crc error, expected 0x%02x 0x%02x, got 0x%02x 0x%02x", expectedCrcHi, expectedCrcLo, crcHi, crcLo);
-                                goto error;
+                                                expected = expected << 1;
+                                }
                         }
+                        expected &= 0xffff;
                 } else {
-                        unsigned char expectedCksum = 0;
-                        int i;
-
                         for (i = 0; i < blockLength; i++)
-                                expectedCksum += blockBuf[i];
-
-                        if (cksum != expectedCksum) {
-                                note_error("checksum error, expected 0x%02x, got 0x%02x", expectedCksum, cksum);
-                                goto error;
-                        }
+                                expected += blockBuf[i];
+                        expected &= 0xff;
+                }
+                if (cksum_crc != expected) {
+                        bb_error_msg(do_crc ? "crc error, expected 0x%04x, got 0x%04x"
+                                           : "checksum error, expected 0x%02x, got 0x%02x",
+                                            expected, cksum_crc);
+                        goto error;
                 }
 
                 wantBlockNo++;
                 length += blockLength;
 
-                if (full_write(filefd, blockBuf, blockLength) < 0) {
-                        note_error("write to file failed: %m");
+                errno = 0;
+                if (full_write(file_fd, blockBuf, blockLength) != blockLength) {
+                        bb_perror_msg("can't write to file");
                         goto fatal;
                 }
-
-        next:
+ next:
                 errors = 0;
                 nak = ACK;
-                write(ttyfd, &nak, 1);
+                full_write(write_fd, &nak, 1);
                 continue;
-
-        error:
-        timeout:
+ error:
+ timeout:
                 errors++;
                 if (errors == MAXERRORS) {
                         /* Abort */
 
-                        // if using crc, try again w/o crc
+                        /* if were asking for crc, try again w/o crc */
                         if (nak == 'C') {
                                 nak = NAK;
                                 errors = 0;
-                                docrc = 0;
+                                do_crc = 0;
                                 goto timeout;
                         }
-
-                        note_error("too many errors; giving up");
-
-                fatal:
-                        /* 5 CAN followed by 5 BS */
-                        write(ttyfd, "\030\030\030\030\030\010\010\010\010\010", 10);
+                        bb_error_msg("too many errors; giving up");
+ fatal:
+                        /* 5 CAN followed by 5 BS. Don't try too hard... */
+                        safe_write(write_fd, "\030\030\030\030\030\010\010\010\010\010", 10);
                         return -1;
                 }
 
                 /* Flush pending input */
-                tcflush(ttyfd, TCIFLUSH);
-
-                write(ttyfd, &nak, 1);
-        }
-
- done:
-        return length;
+                tcflush(read_fd, TCIFLUSH);
 
-#undef note_error
+                full_write(write_fd, &nak, 1);
+        } /* for (;;) */
 }
 
 static void sigalrm_handler(int ATTRIBUTE_UNUSED signum)
@@ -252,40 +220,38 @@ static void sigalrm_handler(int ATTRIBUTE_UNUSED signum)
 int rx_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int rx_main(int argc, char **argv)
 {
-        char *fn;
-        int ttyfd, filefd;
-        struct termios tty, orig_tty;
         struct sigaction act;
+        struct termios tty, orig_tty;
+        int termios_err;
+        int file_fd;
         int n;
-        char error_buf[256];
 
         if (argc != 2)
-                        bb_show_usage();
-
-        fn = argv[1];
-        ttyfd = xopen(CURRENT_TTY, O_RDWR);
-        filefd = xopen(fn, O_RDWR|O_CREAT|O_TRUNC);
-
-        if (tcgetattr(ttyfd, &tty) < 0)
-                        bb_perror_msg_and_die("tcgetattr");
-
-        orig_tty = tty;
-
-        cfmakeraw(&tty);
-        tcsetattr(ttyfd, TCSAFLUSH, &tty);
+                bb_show_usage();
+
+        /* Disabled by vda:
+         * why we can't receive from stdin? Why we *require*
+         * controlling tty?? */
+        /*read_fd = xopen(CURRENT_TTY, O_RDWR);*/
+        file_fd = xopen(argv[1], O_RDWR|O_CREAT|O_TRUNC);
+
+        termios_err = tcgetattr(read_fd, &tty);
+        if (termios_err == 0) {
+                orig_tty = tty;
+                cfmakeraw(&tty);
+                tcsetattr(read_fd, TCSAFLUSH, &tty);
+        }
 
+        /* No SA_RESTART: we want ALRM to interrupt read() */
         memset(&act, 0, sizeof(act));
         act.sa_handler = sigalrm_handler;
-        sigaction(SIGALRM, &act, 0);
-
-        n = receive(error_buf, sizeof(error_buf), ttyfd, filefd);
-
-        close(filefd);
-
-        tcsetattr(ttyfd, TCSAFLUSH, &orig_tty);
+        sigaction(SIGALRM, &act, NULL);
 
-        if (n < 0)
-                bb_error_msg_and_die("\nreceive failed:\n  %s", error_buf);
+        n = receive(file_fd);
 
-        fflush_stdout_and_exit(EXIT_SUCCESS);
+        if (termios_err == 0)
+                tcsetattr(read_fd, TCSAFLUSH, &orig_tty);
+        if (ENABLE_FEATURE_CLEAN_UP)
+                close(file_fd);
+        fflush_stdout_and_exit(n >= 0);
 }