1 /* vi: set sw=4 ts=4: */
2 /*
3 * bare bones version of lpr & lpq: BSD printing utilities
4 *
5 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
6 *
7 * Original idea and code:
8 * Walter Harms <WHarms@bfs.de>
9 *
10 * Licensed under GPLv2, see file LICENSE in this source tree.
11 *
12 * See RFC 1179 for protocol description.
13 */
14 //config:config LPR
15 //config: bool "lpr (9.9 kb)"
16 //config: default y
17 //config: help
18 //config: lpr sends files (or standard input) to a print spooling daemon.
19 //config:
20 //config:config LPQ
21 //config: bool "lpq (9.9 kb)"
22 //config: default y
23 //config: help
24 //config: lpq is a print spool queue examination and manipulation program.
25
26 // APPLET_ODDNAME:name main location suid_type help
27 //applet:IF_LPQ(APPLET_ODDNAME(lpq, lpqr, BB_DIR_USR_BIN, BB_SUID_DROP, lpq))
28 //applet:IF_LPR(APPLET_ODDNAME(lpr, lpqr, BB_DIR_USR_BIN, BB_SUID_DROP, lpr))
29
30 //kbuild:lib-$(CONFIG_LPR) += lpr.o
31 //kbuild:lib-$(CONFIG_LPQ) += lpr.o
32
33 //usage:#define lpr_trivial_usage
34 //usage: "-P queue[@host[:port]] -U USERNAME -J TITLE -Vmh [FILE]..."
35 /* -C CLASS exists too, not shown.
36 * CLASS is supposed to be printed on banner page, if one is requested */
37 //usage:#define lpr_full_usage "\n\n"
38 //usage: " -P lp service to connect to (else uses $PRINTER)"
39 //usage: "\n -m Send mail on completion"
40 //usage: "\n -h Print banner page too"
41 //usage: "\n -V Verbose"
42 //usage:
43 //usage:#define lpq_trivial_usage
44 //usage: "[-P queue[@host[:port]]] [-U USERNAME] [-d JOBID]... [-fs]"
45 //usage:#define lpq_full_usage "\n\n"
46 //usage: " -P lp service to connect to (else uses $PRINTER)"
47 //usage: "\n -d Delete jobs"
48 //usage: "\n -f Force any waiting job to be printed"
49 //usage: "\n -s Short display"
50
51 #include "libbb.h"
52
53 /*
54 * LPD returns binary 0 on success.
55 * Otherwise it returns error message.
56 */
get_response_or_say_and_die(int fd,const char * errmsg)57 static void get_response_or_say_and_die(int fd, const char *errmsg)
58 {
59 ssize_t sz;
60 char buf[128];
61
62 buf[0] = ' ';
63 sz = safe_read(fd, buf, 1);
64 if ('\0' != buf[0]) {
65 // request has failed
66 // try to make sure last char is '\n', but do not add
67 // superfluous one
68 sz = full_read(fd, buf + 1, 126);
69 bb_error_msg("error while %s%s", errmsg,
70 (sz > 0 ? ". Server said:" : ""));
71 if (sz > 0) {
72 // sz = (bytes in buf) - 1
73 if (buf[sz] != '\n')
74 buf[++sz] = '\n';
75 safe_write(STDERR_FILENO, buf, sz + 1);
76 }
77 xfunc_die();
78 }
79 }
80
81 int lpqr_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE;
lpqr_main(int argc UNUSED_PARAM,char * argv[])82 int lpqr_main(int argc UNUSED_PARAM, char *argv[])
83 {
84 enum {
85 OPT_P = 1 << 0, // -P queue[@host[:port]]. If no -P is given use $PRINTER, then "lp@localhost:515"
86 OPT_U = 1 << 1, // -U username
87
88 LPR_V = 1 << 2, // -V: be verbose
89 LPR_h = 1 << 3, // -h: want banner printed
90 LPR_C = 1 << 4, // -C class: job "class" (? supposedly printed on banner)
91 LPR_J = 1 << 5, // -J title: the job title for the banner page
92 LPR_m = 1 << 6, // -m: send mail back to user
93
94 LPQ_SHORT_FMT = 1 << 2, // -s: short listing format
95 LPQ_DELETE = 1 << 3, // -d: delete job(s)
96 LPQ_FORCE = 1 << 4, // -f: force waiting job(s) to be printed
97 };
98 char tempfile[sizeof("/tmp/lprXXXXXX")];
99 const char *job_title;
100 const char *printer_class = ""; // printer class, max 32 char
101 const char *queue; // name of printer queue
102 const char *server = "localhost"; // server[:port] of printer queue
103 char *hostname;
104 // N.B. IMHO getenv("USER") can be way easily spoofed!
105 const char *user = xuid2uname(getuid());
106 unsigned job;
107 unsigned opts;
108 int fd;
109
110 queue = getenv("PRINTER");
111 if (!queue)
112 queue = "lp";
113
114 // parse options
115 // TODO: set opt_complementary: s,d,f are mutually exclusive
116 opts = getopt32(argv,
117 (/*lp*/'r' == applet_name[2]) ? "P:U:VhC:J:m" : "P:U:sdf"
118 , &queue, &user
119 , &printer_class, &job_title
120 );
121 argv += optind;
122
123 {
124 // queue name is to the left of '@'
125 char *s = strchr(queue, '@');
126 if (s) {
127 // server name is to the right of '@'
128 *s = '\0';
129 server = s + 1;
130 }
131 }
132
133 // do connect
134 fd = create_and_connect_stream_or_die(server, 515);
135
136 //
137 // LPQ ------------------------
138 //
139 if (/*lp*/'q' == applet_name[2]) {
140 char cmd;
141 // force printing of every job still in queue
142 if (opts & LPQ_FORCE) {
143 cmd = 1;
144 goto command;
145 // delete job(s)
146 } else if (opts & LPQ_DELETE) {
147 fdprintf(fd, "\x5" "%s %s", queue, user);
148 while (*argv) {
149 fdprintf(fd, " %s", *argv++);
150 }
151 bb_putchar('\n');
152 // dump current jobs status
153 // N.B. periodical polling should be achieved
154 // via "watch -n delay lpq"
155 // They say it's the UNIX-way :)
156 } else {
157 cmd = (opts & LPQ_SHORT_FMT) ? 3 : 4;
158 command:
159 fdprintf(fd, "%c" "%s\n", cmd, queue);
160 bb_copyfd_eof(fd, STDOUT_FILENO);
161 }
162
163 return EXIT_SUCCESS;
164 }
165
166 //
167 // LPR ------------------------
168 //
169 if (opts & LPR_V)
170 bb_simple_error_msg("connected to server");
171
172 job = getpid() % 1000;
173 hostname = safe_gethostname();
174
175 // no files given on command line? -> use stdin
176 if (!*argv)
177 *--argv = (char *)"-";
178
179 fdprintf(fd, "\x2" "%s\n", queue);
180 get_response_or_say_and_die(fd, "setting queue");
181
182 // process files
183 do {
184 unsigned cflen;
185 int dfd;
186 struct stat st;
187 char *c;
188 char *remote_filename;
189 char *controlfile;
190
191 // if data file is stdin, we need to dump it first
192 if (LONE_DASH(*argv)) {
193 strcpy(tempfile, "/tmp/lprXXXXXX");
194 dfd = xmkstemp(tempfile);
195 bb_copyfd_eof(STDIN_FILENO, dfd);
196 xlseek(dfd, 0, SEEK_SET);
197 *argv = (char*)bb_msg_standard_input;
198 } else {
199 dfd = xopen(*argv, O_RDONLY);
200 }
201
202 st.st_size = 0; /* paranoia: fstat may theoretically fail */
203 fstat(dfd, &st);
204
205 /* Apparently, some servers are buggy and won't accept 0-sized jobs.
206 * Standard lpr works around it by refusing to send such jobs:
207 */
208 if (st.st_size == 0) {
209 bb_simple_error_msg("nothing to print");
210 continue;
211 }
212
213 /* "The name ... should start with ASCII "cfA",
214 * followed by a three digit job number, followed
215 * by the host name which has constructed the file."
216 * We supply 'c' or 'd' as needed for control/data file. */
217 remote_filename = xasprintf("fA%03u%s", job, hostname);
218
219 // create control file
220 // TODO: all lines but 2 last are constants! How we can use this fact?
221 controlfile = xasprintf(
222 "H" "%.32s\n" "P" "%.32s\n" /* H HOST, P USER */
223 "C" "%.32s\n" /* C CLASS - printed on banner page (if L cmd is also given) */
224 "J" "%.99s\n" /* J JOBNAME */
225 /* "class name for banner page and job name
226 * for banner page commands must precede L command" */
227 "L" "%.32s\n" /* L USER - print banner page, with given user's name */
228 "M" "%.32s\n" /* M WHOM_TO_MAIL */
229 "l" "d%.31s\n" /* l DATA_FILE_NAME ("dfAxxx") */
230 , hostname, user
231 , printer_class /* can be "" */
232 , ((opts & LPR_J) ? job_title : *argv)
233 , (opts & LPR_h) ? user : ""
234 , (opts & LPR_m) ? user : ""
235 , remote_filename
236 );
237 // delete possible "\nX\n" (that is, one-char) patterns
238 c = controlfile;
239 while ((c = strchr(c, '\n')) != NULL) {
240 if (c[1] && c[2] == '\n') {
241 overlapping_strcpy(c, c+2);
242 } else {
243 c++;
244 }
245 }
246
247 // send control file
248 if (opts & LPR_V)
249 bb_simple_error_msg("sending control file");
250 /* "Acknowledgement processing must occur as usual
251 * after the command is sent." */
252 cflen = (unsigned)strlen(controlfile);
253 fdprintf(fd, "\x2" "%u c%s\n", cflen, remote_filename);
254 get_response_or_say_and_die(fd, "sending control file");
255 /* "Once all of the contents have
256 * been delivered, an octet of zero bits is sent as
257 * an indication that the file being sent is complete.
258 * A second level of acknowledgement processing
259 * must occur at this point." */
260 full_write(fd, controlfile, cflen + 1); /* writes NUL byte too */
261 get_response_or_say_and_die(fd, "sending control file");
262
263 // send data file, with name "dfaXXX"
264 if (opts & LPR_V)
265 bb_simple_error_msg("sending data file");
266 fdprintf(fd, "\x3" "%"OFF_FMT"u d%s\n", st.st_size, remote_filename);
267 get_response_or_say_and_die(fd, "sending data file");
268 if (bb_copyfd_size(dfd, fd, st.st_size) != st.st_size) {
269 // We're screwed. We sent less bytes than we advertised.
270 bb_simple_error_msg_and_die("local file changed size?!");
271 }
272 write(fd, "", 1); // send ACK
273 get_response_or_say_and_die(fd, "sending data file");
274
275 // delete temporary file if we dumped stdin
276 if (*argv == (char*)bb_msg_standard_input)
277 unlink(tempfile);
278
279 // cleanup
280 close(fd);
281 free(remote_filename);
282 free(controlfile);
283
284 // say job accepted
285 if (opts & LPR_V)
286 bb_simple_error_msg("job accepted");
287
288 // next, please!
289 job = (job + 1) % 1000;
290 } while (*++argv);
291
292 return EXIT_SUCCESS;
293 }
294