Linux: Added thread safe getopt

The getopt command uses global variables and is not thread safe.

Created a minimal px4_getopt version that supports options with
or without an arg, and random placement of options on the command line.

This version modifies the order of the args in argv as does the
POSIX version of getopt.

This assumes that argv[0] is the program name. Nuttx may not support
that properly in task_spawn.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

makefiles/linux.mk

@@ -34,5 +34,7 @@
 # building firmware.
 #
 
-MODULES += platforms/linux/px4_layer
+MODULES += \
+		platforms/common \
+		platforms/linux/px4_layer 
 

src/drivers/ms5611/ms5611_linux.cpp

@@ -38,6 +38,7 @@
 
 #include <px4_config.h>
 #include <px4_defines.h>
+#include <px4_getopt.h>
 
 #include <sys/types.h>
 #include <stdint.h>
@@ -1194,21 +1195,6 @@ usage()
 
 } // namespace
 
-static int getopt(int argc, char *argv[], const char *options, int *myoptind)
-{
-	char *p = argv[*myoptind];
-	int idx = 0;
-	if (p && options && myoptind && p[0] == '-') {
-		while (options[idx] != 0 && p[1] != options[idx])
-			++idx;
-		if (options[idx] == 0)
-			return (int)'?';
-		*myoptind += 1;
-		return options[idx];
-	}
-	return -1;
-}
-
 int
 ms5611_main(int argc, char *argv[])
 {
@@ -1223,7 +1209,8 @@ ms5611_main(int argc, char *argv[])
 
 	/* jump over start/off/etc and look at options first */
 	int myoptind = 1;
-	while ((ch = getopt(argc, argv, "XIS", &myoptind)) != EOF) {
+	const char *myoptarg = NULL;
+	while ((ch = px4_getopt(argc, argv, "XIS", &myoptind, &myoptarg)) != EOF) {
 		printf("ch = %d\n", ch);
 		switch (ch) {
 		case 'X':

src/modules/mavlink/mavlink_main_linux.cpp

@@ -40,6 +40,7 @@
  */
 
 #include <px4_config.h>
+#include <px4_getopt.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -1199,38 +1200,36 @@ Mavlink::task_main(int argc, char *argv[])
 	_datarate = 0;
 	_mode = MAVLINK_MODE_NORMAL;
 
-	/* work around some stupidity in task_create's argv handling */
-	argc -= 2;
-	argv += 2;
-
 	/* don't exit from getopt loop to leave getopt global variables in consistent state,
 	 * set error flag instead */
 	bool err_flag = false;
+	int myoptind=1;
+	const char *myoptarg = NULL;
 
-	while ((ch = getopt(argc, argv, "b:r:d:m:fpvwx")) != EOF) {
+	while ((ch = px4_getopt(argc, argv, "b:r:d:m:fpvwx", &myoptind, &myoptarg)) != EOF) {
 		switch (ch) {
 		case 'b':
-			_baudrate = strtoul(optarg, NULL, 10);
+			_baudrate = strtoul(myoptarg, NULL, 10);
 
 			if (_baudrate < 9600 || _baudrate > 921600) {
-				warnx("invalid baud rate '%s'", optarg);
+				warnx("invalid baud rate '%s'", myoptarg);
 				err_flag = true;
 			}
 
 			break;
 
 		case 'r':
-			_datarate = strtoul(optarg, NULL, 10);
+			_datarate = strtoul(myoptarg, NULL, 10);
 
 			if (_datarate < 10 || _datarate > MAX_DATA_RATE) {
-				warnx("invalid data rate '%s'", optarg);
+				warnx("invalid data rate '%s'", myoptarg);
 				err_flag = true;
 			}
 
 			break;
 
 		case 'd':
-			_device_name = optarg;
+			_device_name = myoptarg;
 			break;
 
 //		case 'e':
@@ -1238,13 +1237,13 @@ Mavlink::task_main(int argc, char *argv[])
 //			break;
 
 		case 'm':
-			if (strcmp(optarg, "custom") == 0) {
+			if (strcmp(myoptarg, "custom") == 0) {
 				_mode = MAVLINK_MODE_CUSTOM;
 
-			} else if (strcmp(optarg, "camera") == 0) {
+			} else if (strcmp(myoptarg, "camera") == 0) {
 				// left in here for compatibility
 				_mode = MAVLINK_MODE_ONBOARD;
-			} else if (strcmp(optarg, "onboard") == 0) {
+			} else if (strcmp(myoptarg, "onboard") == 0) {
 				_mode = MAVLINK_MODE_ONBOARD;
 			}
 

src/platforms/common/module.mk

@@ -0,0 +1,6 @@
+#
+# Common OS porting APIs
+#
+
+SRCS		 = px4_getopt.c
+

src/platforms/common/px4_getopt.c

@@ -0,0 +1,152 @@
+/****************************************************************************
+ *
+ * Copyright (c) 2015 Mark Charlebois. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file px4_getopt.cpp
+ * Minimal, thread safe version of getopt
+ */
+
+#include <px4_getopt.h>
+#include <stdio.h>
+
+// check if p is a valid option and if the option takes an arg
+static char isvalidopt(char p, const char *options, int *takesarg)
+{
+	int idx = 0;
+	*takesarg = 0;
+	while (options[idx] != 0 && p != options[idx])
+		++idx;
+	if (options[idx] == 0)
+		return '?';
+	if (options[idx+1] == ':') {
+		*takesarg = 1;
+	}
+	return options[idx];
+}
+
+// reorder argv and put non-options at the end
+static int reorder(int argc, char **argv, const char *options)
+{
+	char *tmp_argv[argc];
+	char c;
+	int idx = 1;
+	int tmpidx = 1;
+	int takesarg;
+
+	// move the options to the front
+	while (idx < argc && argv[idx] != 0) {
+		if (argv[idx][0] == '-') {
+			c = isvalidopt(argv[idx][1], options, &takesarg);
+			if (c == '?')
+				return 1;
+			tmp_argv[tmpidx] = argv[idx];
+			tmpidx++;
+			if (takesarg) {
+				tmp_argv[tmpidx] = argv[idx+1];
+				printf("tmp_argv[%d] = %s\n", tmpidx, tmp_argv[tmpidx]);
+				tmpidx++;
+				idx++;
+			}
+		}
+		idx++;
+	}
+
+	// Add non-options to the end
+	idx = 1;
+	while (idx < argc && argv[idx] != 0) {
+		if (argv[idx][0] == '-') {
+			c = isvalidopt(argv[idx][1], options, &takesarg);
+			if (c == '?')
+				return c;
+			if (takesarg) {
+				idx++;
+			}
+		}
+		else {
+			tmp_argv[tmpidx] = argv[idx];
+			tmpidx++;
+		}
+		idx++;
+	}
+
+	// Reorder argv
+	for (idx=1; idx < argc; idx++) {
+		argv[idx] = tmp_argv[idx];
+	}
+
+	return 0;
+}
+
+//
+// px4_getopt 
+//
+// returns:
+//            the valid option character
+//            '?' if any option is unknown 
+//            -1 if no remaining options
+//
+// If the option takes an arg, myoptarg will be updated accordingly.
+// After each call to px4_getopt, myoptind in incremented to the next
+// unparsed arg index.
+// Argv is changed to put all options and option args at the beginning,
+// followed by non-options.
+//
+int px4_getopt(int argc, char *argv[], const char *options, int *myoptind, const char **myoptarg)
+{
+	char *p;
+	char c;
+	int takesarg;
+
+	if (*myoptind == 1)
+		if (reorder(argc, argv, options) != 0)
+			return (int)'?';
+
+	p = argv[*myoptind];
+
+	if (*myoptarg == 0)
+		*myoptarg = argv[*myoptind];
+
+	if (p && options && myoptind && p[0] == '-') {
+		c = isvalidopt(p[1], options, &takesarg);
+		if (c == '?')
+			return (int)c;
+		*myoptind += 1;
+		if (takesarg) {
+			*myoptarg = argv[*myoptind];
+			*myoptind += 1;
+		}
+		return (int)c;
+	}
+	return -1;
+}
+

src/platforms/linux/drivers/accel/accel.cpp

@@ -52,7 +52,7 @@
 #include <stdio.h>
 #include <math.h>
 #include <unistd.h>
-#include <getopt.h>
+#include <px4_getopt.h>
 
 #include <systemlib/perf_counter.h>
 #include <systemlib/err.h>
@@ -496,7 +496,7 @@ ACCELSIM::init()
 	_accel_topic = orb_advertise_multi(ORB_ID(sensor_accel), &arp,
 		&_accel_orb_class_instance, ORB_PRIO_DEFAULT);
 
-	if (_accel_topic < 0) {
+	if (_accel_topic == (orb_advert_t)(-1)) {
 		warnx("ADVERT ERR");
 	}
 
@@ -1069,7 +1069,12 @@ ACCELSIM::measure()
 
 	if (!(_pub_blocked)) {
 		/* publish it */
-		orb_publish(ORB_ID(sensor_accel), _accel_topic, &accel_report);
+
+		// The first call to measure() is from init() and _accel_topic is not
+		// yet initialized
+		if (_accel_topic != (orb_advert_t)(-1)) {
+			orb_publish(ORB_ID(sensor_accel), _accel_topic, &accel_report);
+		}
 	}
 
 	_accel_read++;
@@ -1332,12 +1337,14 @@ accel_main(int argc, char *argv[])
 	int ch;
 	enum Rotation rotation = ROTATION_NONE;
 	int ret;
+	int myoptind = 1;
+	const char * myoptarg = NULL;
 
 	/* jump over start/off/etc and look at options first */
-	while ((ch = getopt(argc, argv, "R:")) != EOF) {
+	while ((ch = px4_getopt(argc, argv, "R:", &myoptind, &myoptarg)) != EOF) {
 		switch (ch) {
 		case 'R':
-			rotation = (enum Rotation)atoi(optarg);
+			rotation = (enum Rotation)atoi(myoptarg);
 			break;
 		default:
 			accel::usage();
@@ -1345,7 +1352,7 @@ accel_main(int argc, char *argv[])
 		}
 	}
 
-	const char *verb = argv[optind];
+	const char *verb = argv[myoptind];
 
 	/*
 	 * Start/load the driver.

src/platforms/px4_getopt.h

@@ -0,0 +1,46 @@
+/****************************************************************************
+ *
+ * Copyright (C) 2015 Mark Charlebois. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file px4_getopt.h
+ * Thread safe version of getopt
+ */
+
+#pragma once
+
+__BEGIN_DECLS
+
+int px4_getopt(int argc, char *argv[], const char *options, int *myoptind, const char **myoptarg);
+
+__END_DECLS
+