From 52de9c7141f3dc6dbb801a9d1d1429238917ee4a Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 10 Jun 2012 13:47:17 +0200 Subject: [PATCH] lpr: don't send 0-byte print jobs (compat) Signed-off-by: Denys Vlasenko --- printutils/lpr.c | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) diff --git a/printutils/lpr.c b/printutils/lpr.c index 748879542..70cda7717 100644 --- a/printutils/lpr.c +++ b/printutils/lpr.c @@ -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) { -- 2.25.1