1 /* vi: set sw=4 ts=4: */
3 * bare bones version of lpr & lpq: BSD printing utilities
5 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
7 * Original idea and code:
8 * Walter Harms <WHarms@bfs.de>
10 * Licensed under GPLv2, see file LICENSE in this source tree.
12 * See RFC 1179 for protocol description.
18 //config: lpr sends files (or standard input) to a print spooling daemon.
24 //config: lpq is a print spool queue examination and manipulation program.
26 //applet:IF_LPQ(APPLET_ODDNAME(lpq, lpqr, BB_DIR_USR_BIN, BB_SUID_DROP, lpq))
27 //applet:IF_LPR(APPLET_ODDNAME(lpr, lpqr, BB_DIR_USR_BIN, BB_SUID_DROP, lpr))
29 //kbuild:lib-$(CONFIG_LPR) += lpr.o
30 //kbuild:lib-$(CONFIG_LPQ) += lpr.o
32 //usage:#define lpr_trivial_usage
33 //usage: "-P queue[@host[:port]] -U USERNAME -J TITLE -Vmh [FILE]..."
34 /* -C CLASS exists too, not shown.
35 * CLASS is supposed to be printed on banner page, if one is requested */
36 //usage:#define lpr_full_usage "\n\n"
37 //usage: " -P lp service to connect to (else uses $PRINTER)"
38 //usage: "\n -m Send mail on completion"
39 //usage: "\n -h Print banner page too"
40 //usage: "\n -V Verbose"
42 //usage:#define lpq_trivial_usage
43 //usage: "[-P queue[@host[:port]]] [-U USERNAME] [-d JOBID]... [-fs]"
44 //usage:#define lpq_full_usage "\n\n"
45 //usage: " -P lp service to connect to (else uses $PRINTER)"
46 //usage: "\n -d Delete jobs"
47 //usage: "\n -f Force any waiting job to be printed"
48 //usage: "\n -s Short display"
53 * LPD returns binary 0 on success.
54 * Otherwise it returns error message.
56 static void get_response_or_say_and_die(int fd, const char *errmsg)
62 sz = safe_read(fd, buf, 1);
65 // try to make sure last char is '\n', but do not add
67 sz = full_read(fd, buf + 1, 126);
68 bb_error_msg("error while %s%s", errmsg,
69 (sz > 0 ? ". Server said:" : ""));
71 // sz = (bytes in buf) - 1
74 safe_write(STDERR_FILENO, buf, sz + 1);
80 int lpqr_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE;
81 int lpqr_main(int argc UNUSED_PARAM, char *argv[])
84 OPT_P = 1 << 0, // -P queue[@host[:port]]. If no -P is given use $PRINTER, then "lp@localhost:515"
85 OPT_U = 1 << 1, // -U username
87 LPR_V = 1 << 2, // -V: be verbose
88 LPR_h = 1 << 3, // -h: want banner printed
89 LPR_C = 1 << 4, // -C class: job "class" (? supposedly printed on banner)
90 LPR_J = 1 << 5, // -J title: the job title for the banner page
91 LPR_m = 1 << 6, // -m: send mail back to user
93 LPQ_SHORT_FMT = 1 << 2, // -s: short listing format
94 LPQ_DELETE = 1 << 3, // -d: delete job(s)
95 LPQ_FORCE = 1 << 4, // -f: force waiting job(s) to be printed
97 char tempfile[sizeof("/tmp/lprXXXXXX")];
98 const char *job_title;
99 const char *printer_class = ""; // printer class, max 32 char
100 const char *queue; // name of printer queue
101 const char *server = "localhost"; // server[:port] of printer queue
103 // N.B. IMHO getenv("USER") can be way easily spoofed!
104 const char *user = xuid2uname(getuid());
109 queue = getenv("PRINTER");
114 // TODO: set opt_complementary: s,d,f are mutually exclusive
115 opts = getopt32(argv,
116 (/*lp*/'r' == applet_name[2]) ? "P:U:VhC:J:m" : "P:U:sdf"
118 , &printer_class, &job_title
123 // queue name is to the left of '@'
124 char *s = strchr(queue, '@');
126 // server name is to the right of '@'
133 fd = create_and_connect_stream_or_die(server, 515);
136 // LPQ ------------------------
138 if (/*lp*/'q' == applet_name[2]) {
140 // force printing of every job still in queue
141 if (opts & LPQ_FORCE) {
145 } else if (opts & LPQ_DELETE) {
146 fdprintf(fd, "\x5" "%s %s", queue, user);
148 fdprintf(fd, " %s", *argv++);
151 // dump current jobs status
152 // N.B. periodical polling should be achieved
153 // via "watch -n delay lpq"
154 // They say it's the UNIX-way :)
156 cmd = (opts & LPQ_SHORT_FMT) ? 3 : 4;
158 fdprintf(fd, "%c" "%s\n", cmd, queue);
159 bb_copyfd_eof(fd, STDOUT_FILENO);
166 // LPR ------------------------
169 bb_error_msg("connected to server");
171 job = getpid() % 1000;
172 hostname = safe_gethostname();
174 // no files given on command line? -> use stdin
176 *--argv = (char *)"-";
178 fdprintf(fd, "\x2" "%s\n", queue);
179 get_response_or_say_and_die(fd, "setting queue");
187 char *remote_filename;
190 // if data file is stdin, we need to dump it first
191 if (LONE_DASH(*argv)) {
192 strcpy(tempfile, "/tmp/lprXXXXXX");
193 dfd = xmkstemp(tempfile);
194 bb_copyfd_eof(STDIN_FILENO, dfd);
195 xlseek(dfd, 0, SEEK_SET);
196 *argv = (char*)bb_msg_standard_input;
198 dfd = xopen(*argv, O_RDONLY);
201 st.st_size = 0; /* paranoia: fstat may theoretically fail */
204 /* Apparently, some servers are buggy and won't accept 0-sized jobs.
205 * Standard lpr works around it by refusing to send such jobs:
207 if (st.st_size == 0) {
208 bb_error_msg("nothing to print");
212 /* "The name ... should start with ASCII "cfA",
213 * followed by a three digit job number, followed
214 * by the host name which has constructed the file."
215 * We supply 'c' or 'd' as needed for control/data file. */
216 remote_filename = xasprintf("fA%03u%s", job, hostname);
218 // create control file
219 // TODO: all lines but 2 last are constants! How we can use this fact?
220 controlfile = xasprintf(
221 "H" "%.32s\n" "P" "%.32s\n" /* H HOST, P USER */
222 "C" "%.32s\n" /* C CLASS - printed on banner page (if L cmd is also given) */
223 "J" "%.99s\n" /* J JOBNAME */
224 /* "class name for banner page and job name
225 * for banner page commands must precede L command" */
226 "L" "%.32s\n" /* L USER - print banner page, with given user's name */
227 "M" "%.32s\n" /* M WHOM_TO_MAIL */
228 "l" "d%.31s\n" /* l DATA_FILE_NAME ("dfAxxx") */
230 , printer_class /* can be "" */
231 , ((opts & LPR_J) ? job_title : *argv)
232 , (opts & LPR_h) ? user : ""
233 , (opts & LPR_m) ? user : ""
236 // delete possible "\nX\n" (that is, one-char) patterns
238 while ((c = strchr(c, '\n')) != NULL) {
239 if (c[1] && c[2] == '\n') {
240 overlapping_strcpy(c, c+2);
248 bb_error_msg("sending control file");
249 /* "Acknowledgement processing must occur as usual
250 * after the command is sent." */
251 cflen = (unsigned)strlen(controlfile);
252 fdprintf(fd, "\x2" "%u c%s\n", cflen, remote_filename);
253 get_response_or_say_and_die(fd, "sending control file");
254 /* "Once all of the contents have
255 * been delivered, an octet of zero bits is sent as
256 * an indication that the file being sent is complete.
257 * A second level of acknowledgement processing
258 * must occur at this point." */
259 full_write(fd, controlfile, cflen + 1); /* writes NUL byte too */
260 get_response_or_say_and_die(fd, "sending control file");
262 // send data file, with name "dfaXXX"
264 bb_error_msg("sending data file");
265 fdprintf(fd, "\x3" "%"OFF_FMT"u d%s\n", st.st_size, remote_filename);
266 get_response_or_say_and_die(fd, "sending data file");
267 if (bb_copyfd_size(dfd, fd, st.st_size) != st.st_size) {
268 // We're screwed. We sent less bytes than we advertised.
269 bb_error_msg_and_die("local file changed size?!");
271 write(fd, "", 1); // send ACK
272 get_response_or_say_and_die(fd, "sending data file");
274 // delete temporary file if we dumped stdin
275 if (*argv == (char*)bb_msg_standard_input)
280 free(remote_filename);
285 bb_error_msg("job accepted");
288 job = (job + 1) % 1000;