lpr and lpq applets by Walter Harms.

text    data     bss     dec     hex filename
    392       0       0     392     188 lpq.o
   1378       0       0    1378     562 lpr.o
    142       0       0     142      8e parse_prt.o

printutils/lpr.c

@@ -0,0 +1,200 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Copyright 2008 Walter Harms (WHarms@bfs.de)
+ *
+ * Licensed under the GPL v2, see the file LICENSE in this tarball.
+ */
+#include "libbb.h"
+#include "lpr.h"
+
+static char *mygethostname31(void)
+{
+	char *s = xzalloc(32);
+	if (gethostname(s, 31) < 0)
+		bb_perror_msg_and_die("gethostname");
+	/* gethostname() does not guarantee NUL-termination. xzalloc does. */
+	return s;
+}
+
+static int xmkstemp(char *temp_name)
+{
+	int fd;
+
+	fd = mkstemp(temp_name);
+	if (fd < 0)
+		bb_perror_msg_and_die("mkstemp");
+	return fd;
+}
+
+/* lpd server sends NUL byte on success.
+ * Else read the errormessage and exit.
+ */
+static void get_response(int server_sock, const char *emsg)
+{
+	char buf = '\0';
+
+	safe_read(server_sock, &buf, 1);
+	if (buf != '\0') {
+		bb_error_msg("%s. Server said:", emsg);
+		fputc(buf, stderr);
+		logmode = 0; /* no errors from bb_copyfd_eof() */
+		bb_copyfd_eof(server_sock, STDERR_FILENO);
+		xfunc_die();
+	}
+}
+
+int lpr_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE;
+int lpr_main(int argc, char *argv[])
+{
+	struct netprint netprint;
+	char temp_name[] = "/tmp/lprXXXXXX"; /* for mkstemp */
+	char *strings[5];
+	const char *netopt;
+	const char *jobtitle;
+	const char *hostname;
+	const char *jobclass;
+	char *logname;
+	int pid1000;
+	int server_sock, tmp_fd;
+	unsigned opt;
+	enum {
+		VERBOSE = 1 << 0,
+		USE_HEADER = 1 << 1, /* -h banner or header for this job */
+		USE_MAIL = 1 << 2, /* send mail to user@hostname */
+		OPT_U = 1 << 3, /* -U <username> */
+		OPT_J = 1 << 4, /* -J <title> is the jobtitle for the banner page */
+		OPT_C = 1 << 5, /* -C <class> job classification */
+		OPT_P = 1 << 6, /* -P <queue[@host[:port]]> */
+		/* if no -P is given use $PRINTER, then "lp@localhost:515" */
+	};
+
+	/* Set defaults, parse options */
+	hostname = mygethostname31();
+	netopt = NULL;
+	logname = getenv("LOGNAME");
+	if (logname == NULL)
+		logname = (char*)"user"; /* TODO: getpwuid(getuid())->pw_name? */
+	opt = getopt32(argv, "VhmU:J:C:P:",
+			&logname, &jobtitle, &jobclass, &netopt);
+	argv += optind;
+	parse_prt(netopt, &netprint);
+	logname = xstrndup(logname, 31);
+
+	/* For stdin we need to save it to a tempfile,
+	 * otherwise we can't know the size. */
+	tmp_fd = -1;
+	if (!*argv) {
+		if (jobtitle == NULL)
+			jobtitle = (char *) bb_msg_standard_input;
+
+		tmp_fd = xmkstemp(temp_name);
+		if (bb_copyfd_eof(STDIN_FILENO, tmp_fd) < 0)
+			goto del_temp_file;
+		/* TODO: we actually can have deferred write errors... */
+		close(tmp_fd);
+		argv--; /* back off from NULL */
+		*argv = temp_name;
+	}
+
+	if (opt & VERBOSE)
+		puts("connect to server");
+	server_sock = xconnect_stream(netprint.lsa);
+
+	/* "Receive a printer job" command */
+	fdprintf(server_sock, "\x2" "%s\n", netprint.queue);
+	get_response(server_sock, "set queue failed");
+
+	pid1000 = getpid() % 1000;
+	while (*argv) {
+		char dfa_name[sizeof("dfAnnn") + 32];
+		struct stat st;
+		char **sptr;
+		unsigned size;
+		int fd;
+
+		fd = xopen(*argv, O_RDONLY);
+
+		/* "The name ... should start with ASCII "dfA",
+		 * followed by a three digit job number, followed
+		 * by the host name which has constructed the file." */
+		snprintf(dfa_name, sizeof(dfa_name),
+			"dfA%03u%s", pid1000, hostname);
+		pid1000 = (pid1000 + 1) % 1000;
+
+		/*
+		 * Generate control file contents
+		 */
+		/* H HOST, P USER, l DATA_FILE_NAME, J JOBNAME */
+		strings[0] = xasprintf("H%.32s\n" "P%.32s\n" "l%.32s\n"
+			"J%.99s\n",
+			hostname, logname, dfa_name,
+			!(opt & OPT_J) ? *argv : jobtitle);
+		sptr = &strings[1];
+		/* C CLASS - printed on banner page (if L cmd is also given) */
+		if (opt & OPT_J) /* [1] */
+			*sptr++ = xasprintf("C%.32s\n", jobclass);
+		/* M WHOM_TO_MAIL */
+		if (opt & USE_MAIL) /* [2] */
+			*sptr++ = xasprintf("M%.32s\n", logname);
+		/* H USER - print banner page, with given user's name */
+		if (opt & USE_HEADER) /* [3] */
+			*sptr++ = xasprintf("L%.32s\n", logname);
+		*sptr = NULL; /* [4] max */
+
+		/* RFC 1179: "LPR servers MUST be able
+		 * to receive the control file subcommand first
+		 * and SHOULD be able to receive the data file
+		 * subcommand first".
+		 * Ok, we'll send control file first. */
+		size = 0;
+		sptr = strings;
+		while (*sptr)
+			size += strlen(*sptr++);
+		if (opt & VERBOSE)
+			puts("send control file");
+		/* 2: "Receive control file" subcommand */
+		fdprintf(server_sock, "\x2" "%u c%s\n", size, dfa_name + 1);
+		sptr = strings;
+		while (*sptr) {
+			xwrite(server_sock, *sptr, strlen(*sptr));
+			free(*sptr);
+			sptr++;
+		}
+		free(strings);
+		/* "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." */
+		xwrite(server_sock, "", 1);
+		get_response(server_sock, "send control file failed");
+
+		/* Sending data */
+		st.st_size = 0; /* paranoia */
+		fstat(fd, &st);
+		if (opt & VERBOSE)
+			puts("send data file");
+		/* 3: "Receive data file" subcommand */
+		fdprintf(server_sock, "\x3" "%"OFF_FMT"u %s\n", st.st_size, dfa_name);
+		/* TODO: if file shrank and we wrote less than st.st_size,
+		 * pad output with NUL bytes? Otherwise server won't know
+		 * that we are done. */
+		if (bb_copyfd_size(fd, server_sock, st.st_size) < 0)
+			xfunc_die();
+		close(fd);
+		xwrite(server_sock, "", 1);
+		get_response(server_sock, "send file failed");
+
+		argv++;
+	}
+
+	if (ENABLE_FEATURE_CLEAN_UP)
+		close(server_sock);
+
+	if (tmp_fd >= 0) {
+ del_temp_file:
+		unlink(temp_name);
+	}
+
+	return 0;
+}