lpd,lpr: send/receive ACKs after filenames, not only after file bodies.

lpqr_main                                           1114    1149     +35
lpd_main                                             748     768     +20
This commit is contained in:
Denis Vlasenko 2008-07-22 19:15:30 +00:00
parent e99a92dc2f
commit c445758708
2 changed files with 22 additions and 7 deletions

View File

@ -236,6 +236,9 @@ int lpd_main(int argc UNUSED_PARAM, char *argv[])
fd = xopen(queue, O_RDWR | O_APPEND);
}
// signal OK
safe_write(STDOUT_FILENO, "", 1);
// copy the file
real_len = bb_copyfd_size(STDIN_FILENO, fd, expected_len);
if (real_len != expected_len) {
@ -243,7 +246,7 @@ int lpd_main(int argc UNUSED_PARAM, char *argv[])
expected_len, real_len);
goto err_exit;
}
// get ACK and see whether it is NUL (ok)
// get EOF indicator, see whether it is NUL (ok)
// (and don't trash s[0]!)
if (safe_read(STDIN_FILENO, &s[1], 1) != 1 || s[1] != 0) {
// don't send error msg to peer - it obviously
@ -262,6 +265,9 @@ int lpd_main(int argc UNUSED_PARAM, char *argv[])
free(s);
close(fd); // NB: can do close(-1). Who cares?
// NB: don't do "signal OK" write here, it will be done
// at the top of the loop
} // while (1)
err_exit:

View File

@ -149,6 +149,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
// process files
do {
unsigned cflen;
int dfd;
struct stat st;
char *c;
@ -194,23 +195,30 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
);
// delete possible "\nX\n" patterns
c = controlfile;
cflen = (unsigned)strlen(controlfile);
while ((c = strchr(c, '\n')) != NULL) {
c++;
while (c[0] && c[1] == '\n')
memmove(c, c+2, strlen(c+1)); /* strlen(c+1) == strlen(c+2) + 1 */
if (c[1] && c[2] == '\n') {
/* can't use strcpy, results are undefined */
memmove(c, c+2, cflen - (c-controlfile) - 1);
cflen -= 2;
} else {
c++;
}
}
// send control file
if (opts & LPR_V)
bb_error_msg("sending control file");
/* "Acknowledgement processing must occur as usual
* after the command is sent." */
fdprintf(fd, "\x2" "%u c%s\n", cflen, remote_filename);
get_response_or_say_and_die(fd, "sending control file");
/* "Once all of the contents have
* been delivered, an octet of zero bits is sent as
* an indication that the file being sent is complete.
* A second level of acknowledgement processing
* must occur at this point." */
fdprintf(fd, "\x2" "%u c%s\n" "%s" "%c",
(unsigned)strlen(controlfile),
remote_filename, controlfile, '\0');
full_write(fd, controlfile, cflen + 1); /* writes NUL byte too */
get_response_or_say_and_die(fd, "sending control file");
// send data file, with name "dfaXXX"
@ -219,6 +227,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
st.st_size = 0; /* paranoia: fstat may theoretically fail */
fstat(dfd, &st);
fdprintf(fd, "\x3" "%"OFF_FMT"u d%s\n", st.st_size, remote_filename);
get_response_or_say_and_die(fd, "sending data file");
if (bb_copyfd_size(dfd, fd, st.st_size) != st.st_size) {
// We're screwed. We sent less bytes than we advertised.
bb_error_msg_and_die("local file changed size?!");