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lpr: don't send 0-byte print jobs (compat)

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Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2012-06-10 13:47:17 +02:00
parent cfc212cdff
commit 52de9c7141
1 changed files with 17 additions and 13 deletions
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30
printutils/lpr.c
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@ -89,6 +89,10 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
unsigned opts;
int fd;
queue = getenv("PRINTER");
if (!queue)
queue = "lp";
// parse options
// TODO: set opt_complementary: s,d,f are mutually exclusive
opts = getopt32(argv,
@ -98,16 +102,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
);
argv += optind;
// if queue is not specified -> use $PRINTER
if (!(opts & OPT_P))
queue = getenv("PRINTER");
// if queue is still not specified ->
if (!queue) {
// ... queue defaults to "lp"
// server defaults to "localhost"
queue = "lp";
// if queue is specified ->
} else {
{
// queue name is to the left of '@'
char *s = strchr(queue, '@');
if (s) {
@ -186,6 +181,17 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
dfd = xopen(*argv, O_RDONLY);
}
st.st_size = 0; /* paranoia: fstat may theoretically fail */
fstat(dfd, &st);
/* Apparently, some servers are buggy and won't accept 0-sized jobs.
* Standard lpr works around it by refusing to send such jobs:
*/
if (st.st_size == 0) {
bb_error_msg("nothing to print");
continue;
}
/* "The name ... should start with ASCII "cfA",
* followed by a three digit job number, followed
* by the host name which has constructed the file."
@ -210,7 +216,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
, (opts & LPR_m) ? user : ""
, remote_filename
);
// delete possible "\nX\n" patterns
// delete possible "\nX\n" (that is, one-char) patterns
c = controlfile;
while ((c = strchr(c, '\n')) != NULL) {
if (c[1] && c[2] == '\n') {
@ -239,8 +245,6 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
// send data file, with name "dfaXXX"
if (opts & LPR_V)
bb_error_msg("sending data file");
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) {