[libserialport.git] / linux.c

/*
 * This file is part of the libserialport project.
 *
 * Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
 * Copyright (C) 2014 Aurelien Jacobs <aurel@gnuage.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <config.h>
#include "libserialport.h"
#include "libserialport_internal.h"

/*
 * The 'e' modifier for O_CLOEXEC is glibc >= 2.7 only, hence not
 * portable, so provide an own wrapper for this functionality.
 */
static FILE *fopen_cloexec_rdonly(const char *pathname)
{
	int fd;
	if ((fd = open(pathname, O_RDONLY | O_CLOEXEC)) < 0)
		return NULL;
	return fdopen(fd, "r");
}

SP_PRIV enum sp_return get_port_details(struct sp_port *port)
{
	/*
	 * Description limited to 127 char, anything longer
	 * would not be user friendly anyway.
	 */
	char description[128];
	int bus, address;
	unsigned int vid, pid;
	char manufacturer[128], product[128], serial[128];
	char baddr[32];
	const char dir_name[] = "/sys/class/tty/%s/device/%s%s";
	char sub_dir[32] = "", link_name[PATH_MAX], file_name[PATH_MAX];
	char *ptr, *dev = port->name + 5;
	FILE *file;
	int i, count;
	struct stat statbuf;

	if (strncmp(port->name, "/dev/", 5))
		RETURN_ERROR(SP_ERR_ARG, "Device name not recognized");

	snprintf(link_name, sizeof(link_name), "/sys/class/tty/%s", dev);
	if (lstat(link_name, &statbuf) == -1)
		RETURN_ERROR(SP_ERR_ARG, "Device not found");
	if (!S_ISLNK(statbuf.st_mode))
		snprintf(link_name, sizeof(link_name), "/sys/class/tty/%s/device", dev);
	count = readlink(link_name, file_name, sizeof(file_name));
	if (count <= 0 || count >= (int)(sizeof(file_name) - 1))
		RETURN_ERROR(SP_ERR_ARG, "Device not found");
	file_name[count] = 0;
	if (strstr(file_name, "bluetooth"))
		port->transport = SP_TRANSPORT_BLUETOOTH;
	else if (strstr(file_name, "usb"))
		port->transport = SP_TRANSPORT_USB;

	if (port->transport == SP_TRANSPORT_USB) {
		for (i = 0; i < 5; i++) {
			strcat(sub_dir, "../");

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "busnum");
			if (!(file = fopen_cloexec_rdonly(file_name)))
				continue;
			count = fscanf(file, "%d", &bus);
			fclose(file);
			if (count != 1)
				continue;

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "devnum");
			if (!(file = fopen_cloexec_rdonly(file_name)))
				continue;
			count = fscanf(file, "%d", &address);
			fclose(file);
			if (count != 1)
				continue;

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "idVendor");
			if (!(file = fopen_cloexec_rdonly(file_name)))
				continue;
			count = fscanf(file, "%4x", &vid);
			fclose(file);
			if (count != 1)
				continue;

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "idProduct");
			if (!(file = fopen_cloexec_rdonly(file_name)))
				continue;
			count = fscanf(file, "%4x", &pid);
			fclose(file);
			if (count != 1)
				continue;

			port->usb_bus = bus;
			port->usb_address = address;
			port->usb_vid = vid;
			port->usb_pid = pid;

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "product");
			if ((file = fopen_cloexec_rdonly(file_name))) {
				if ((ptr = fgets(description, sizeof(description), file))) {
					ptr = description + strlen(description) - 1;
					if (ptr >= description && *ptr == '\n')
						*ptr = 0;
					port->description = strdup(description);
				}
				fclose(file);
			}
			if (!file || !ptr)
				port->description = strdup(dev);

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "manufacturer");
			if ((file = fopen_cloexec_rdonly(file_name))) {
				if ((ptr = fgets(manufacturer, sizeof(manufacturer), file))) {
					ptr = manufacturer + strlen(manufacturer) - 1;
					if (ptr >= manufacturer && *ptr == '\n')
						*ptr = 0;
					port->usb_manufacturer = strdup(manufacturer);
				}
				fclose(file);
			}

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "product");
			if ((file = fopen_cloexec_rdonly(file_name))) {
				if ((ptr = fgets(product, sizeof(product), file))) {
					ptr = product + strlen(product) - 1;
					if (ptr >= product && *ptr == '\n')
						*ptr = 0;
					port->usb_product = strdup(product);
				}
				fclose(file);
			}

			snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "serial");
			if ((file = fopen_cloexec_rdonly(file_name))) {
				if ((ptr = fgets(serial, sizeof(serial), file))) {
					ptr = serial + strlen(serial) - 1;
					if (ptr >= serial && *ptr == '\n')
						*ptr = 0;
					port->usb_serial = strdup(serial);
				}
				fclose(file);
			}

			/* If present, add serial to description for better identification. */
			if (port->usb_serial && strlen(port->usb_serial)) {
				snprintf(description, sizeof(description),
					"%s - %s", port->description, port->usb_serial);
				if (port->description)
					free(port->description);
				port->description = strdup(description);
			}

			break;
		}
	} else {
		port->description = strdup(dev);

		if (port->transport == SP_TRANSPORT_BLUETOOTH) {
			snprintf(file_name, sizeof(file_name), dir_name, dev, "", "address");
			if ((file = fopen_cloexec_rdonly(file_name))) {
				if ((ptr = fgets(baddr, sizeof(baddr), file))) {
					ptr = baddr + strlen(baddr) - 1;
					if (ptr >= baddr && *ptr == '\n')
						*ptr = 0;
					port->bluetooth_address = strdup(baddr);
				}
				fclose(file);
			}
		}
	}

	RETURN_OK();
}

SP_PRIV enum sp_return list_ports(struct sp_port ***list)
{
	char name[PATH_MAX], target[PATH_MAX];
	struct dirent *entry;
#ifdef HAVE_STRUCT_SERIAL_STRUCT
	struct serial_struct serial_info;
	int ioctl_result;
#endif
	char buf[sizeof(entry->d_name) + 23];
	int len, fd;
	DIR *dir;
	int ret = SP_OK;
	struct stat statbuf;

	DEBUG("Enumerating tty devices");
	if (!(dir = opendir("/sys/class/tty")))
		RETURN_FAIL("Could not open /sys/class/tty");

	DEBUG("Iterating over results");
	while ((entry = readdir(dir))) {
		snprintf(buf, sizeof(buf), "/sys/class/tty/%s", entry->d_name);
		if (lstat(buf, &statbuf) == -1)
			continue;
		if (!S_ISLNK(statbuf.st_mode))
			snprintf(buf, sizeof(buf), "/sys/class/tty/%s/device", entry->d_name);
		len = readlink(buf, target, sizeof(target));
		if (len <= 0 || len >= (int)(sizeof(target) - 1))
			continue;
		target[len] = 0;
		if (strstr(target, "virtual"))
			continue;
		snprintf(name, sizeof(name), "/dev/%s", entry->d_name);
		DEBUG_FMT("Found device %s", name);
		if (strstr(target, "serial8250")) {
			/*
			 * The serial8250 driver has a hardcoded number of ports.
			 * The only way to tell which actually exist on a given system
			 * is to try to open them and make an ioctl call.
			 */
			DEBUG("serial8250 device, attempting to open");
			if ((fd = open(name, O_RDWR | O_NONBLOCK | O_NOCTTY | O_CLOEXEC)) < 0) {
				DEBUG("Open failed, skipping");
				continue;
			}
#ifdef HAVE_STRUCT_SERIAL_STRUCT
			ioctl_result = ioctl(fd, TIOCGSERIAL, &serial_info);
#endif
			close(fd);
#ifdef HAVE_STRUCT_SERIAL_STRUCT
			if (ioctl_result != 0) {
				DEBUG("ioctl failed, skipping");
				continue;
			}
			if (serial_info.type == PORT_UNKNOWN) {
				DEBUG("Port type is unknown, skipping");
				continue;
			}
#endif
		}
		DEBUG_FMT("Found port %s", name);
		*list = list_append(*list, name);
		if (!*list) {
			SET_ERROR(ret, SP_ERR_MEM, "List append failed");
			break;
		}
	}
	closedir(dir);

	return ret;
}
Commit	Line	Data
e33dcf90 ML	1	/*
	2	* This file is part of the libserialport project.
	3	*
f77bb46d	4	* Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
e33dcf90 ML	5	* Copyright (C) 2014 Aurelien Jacobs <aurel@gnuage.org>
	6	*
	7	* This program is free software: you can redistribute it and/or modify
	8	* it under the terms of the GNU Lesser General Public License as
	9	* published by the Free Software Foundation, either version 3 of the
	10	* License, or (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public License
	18	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	19	*/
	20
1a584c45	21	#include <config.h>
e33dcf90 ML	22	#include "libserialport.h"
	23	#include "libserialport_internal.h"
	24
fa106ef1 CS	25	/*
	26	* The 'e' modifier for O_CLOEXEC is glibc >= 2.7 only, hence not
	27	* portable, so provide an own wrapper for this functionality.
	28	*/
	29	static FILE fopen_cloexec_rdonly(const char pathname)
	30	{
	31	int fd;
	32	if ((fd = open(pathname, O_RDONLY \| O_CLOEXEC)) < 0)
	33	return NULL;
	34	return fdopen(fd, "r");
	35	}
	36
970f279a	37	SP_PRIV enum sp_return get_port_details(struct sp_port *port)
e33dcf90	38	{
dc422c04 UH	39	/*
	40	* Description limited to 127 char, anything longer
	41	* would not be user friendly anyway.
	42	*/
e33dcf90	43	char description[128];
0666ccc7 ML	44	int bus, address;
0666ccc7 ML	45	unsigned int vid, pid;
e33dcf90 ML	46	char manufacturer[128], product[128], serial[128];
	47	char baddr[32];
	48	const char dir_name[] = "/sys/class/tty/%s/device/%s%s";
9118f753	49	char sub_dir[32] = "", link_name[PATH_MAX], file_name[PATH_MAX];
e33dcf90 ML	50	char ptr, dev = port->name + 5;
	51	FILE *file;
	52	int i, count;
46d8b0a0	53	struct stat statbuf;
e33dcf90 ML	54
e33dcf90 ML	55	if (strncmp(port->name, "/dev/", 5))
dc422c04	56	RETURN_ERROR(SP_ERR_ARG, "Device name not recognized");
e33dcf90	57
9118f753 ML	58	snprintf(link_name, sizeof(link_name), "/sys/class/tty/%s", dev);
9118f753 ML	59	if (lstat(link_name, &statbuf) == -1)
46d8b0a0	60	RETURN_ERROR(SP_ERR_ARG, "Device not found");
46d8b0a0	61	if (!S_ISLNK(statbuf.st_mode))
9118f753 ML	62	snprintf(link_name, sizeof(link_name), "/sys/class/tty/%s/device", dev);
9118f753 ML	63	count = readlink(link_name, file_name, sizeof(file_name));
dc422c04 UH	64	if (count <= 0 \|\| count >= (int)(sizeof(file_name) - 1))
dc422c04 UH	65	RETURN_ERROR(SP_ERR_ARG, "Device not found");
e33dcf90 ML	66	file_name[count] = 0;
	67	if (strstr(file_name, "bluetooth"))
	68	port->transport = SP_TRANSPORT_BLUETOOTH;
	69	else if (strstr(file_name, "usb"))
	70	port->transport = SP_TRANSPORT_USB;
	71
	72	if (port->transport == SP_TRANSPORT_USB) {
dc422c04	73	for (i = 0; i < 5; i++) {
e33dcf90 ML	74	strcat(sub_dir, "../");
	75
	76	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "busnum");
fa106ef1	77	if (!(file = fopen_cloexec_rdonly(file_name)))
e33dcf90 ML	78	continue;
	79	count = fscanf(file, "%d", &bus);
	80	fclose(file);
	81	if (count != 1)
	82	continue;
	83
	84	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "devnum");
fa106ef1	85	if (!(file = fopen_cloexec_rdonly(file_name)))
e33dcf90 ML	86	continue;
	87	count = fscanf(file, "%d", &address);
	88	fclose(file);
	89	if (count != 1)
	90	continue;
	91
	92	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "idVendor");
fa106ef1	93	if (!(file = fopen_cloexec_rdonly(file_name)))
e33dcf90 ML	94	continue;
	95	count = fscanf(file, "%4x", &vid);
	96	fclose(file);
	97	if (count != 1)
	98	continue;
	99
	100	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "idProduct");
fa106ef1	101	if (!(file = fopen_cloexec_rdonly(file_name)))
e33dcf90 ML	102	continue;
	103	count = fscanf(file, "%4x", &pid);
	104	fclose(file);
	105	if (count != 1)
	106	continue;
	107
	108	port->usb_bus = bus;
	109	port->usb_address = address;
	110	port->usb_vid = vid;
	111	port->usb_pid = pid;
	112
	113	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "product");
fa106ef1	114	if ((file = fopen_cloexec_rdonly(file_name))) {
e33dcf90 ML	115	if ((ptr = fgets(description, sizeof(description), file))) {
	116	ptr = description + strlen(description) - 1;
	117	if (ptr >= description && *ptr == '\n')
	118	*ptr = 0;
	119	port->description = strdup(description);
	120	}
	121	fclose(file);
	122	}
	123	if (!file \|\| !ptr)
	124	port->description = strdup(dev);
	125
	126	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "manufacturer");
fa106ef1	127	if ((file = fopen_cloexec_rdonly(file_name))) {
e33dcf90 ML	128	if ((ptr = fgets(manufacturer, sizeof(manufacturer), file))) {
	129	ptr = manufacturer + strlen(manufacturer) - 1;
	130	if (ptr >= manufacturer && *ptr == '\n')
	131	*ptr = 0;
	132	port->usb_manufacturer = strdup(manufacturer);
	133	}
	134	fclose(file);
	135	}
	136
	137	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "product");
fa106ef1	138	if ((file = fopen_cloexec_rdonly(file_name))) {
e33dcf90 ML	139	if ((ptr = fgets(product, sizeof(product), file))) {
	140	ptr = product + strlen(product) - 1;
	141	if (ptr >= product && *ptr == '\n')
	142	*ptr = 0;
	143	port->usb_product = strdup(product);
	144	}
	145	fclose(file);
	146	}
	147
	148	snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "serial");
fa106ef1	149	if ((file = fopen_cloexec_rdonly(file_name))) {
e33dcf90 ML	150	if ((ptr = fgets(serial, sizeof(serial), file))) {
	151	ptr = serial + strlen(serial) - 1;
	152	if (ptr >= serial && *ptr == '\n')
	153	*ptr = 0;
	154	port->usb_serial = strdup(serial);
	155	}
	156	fclose(file);
	157	}
	158
ea17bfca UJ	159	/* If present, add serial to description for better identification. */
ea17bfca UJ	160	if (port->usb_serial && strlen(port->usb_serial)) {
7c1101dc	161	snprintf(description, sizeof(description),
ea17bfca UJ	162	"%s - %s", port->description, port->usb_serial);
	163	if (port->description)
	164	free(port->description);
	165	port->description = strdup(description);
	166	}
	167
e33dcf90 ML	168	break;
	169	}
	170	} else {
	171	port->description = strdup(dev);
	172
	173	if (port->transport == SP_TRANSPORT_BLUETOOTH) {
	174	snprintf(file_name, sizeof(file_name), dir_name, dev, "", "address");
fa106ef1	175	if ((file = fopen_cloexec_rdonly(file_name))) {
e33dcf90 ML	176	if ((ptr = fgets(baddr, sizeof(baddr), file))) {
	177	ptr = baddr + strlen(baddr) - 1;
	178	if (ptr >= baddr && *ptr == '\n')
	179	*ptr = 0;
	180	port->bluetooth_address = strdup(baddr);
	181	}
	182	fclose(file);
	183	}
	184	}
	185	}
	186
	187	RETURN_OK();
	188	}
48a4076f	189
970f279a	190	SP_PRIV enum sp_return list_ports(struct sp_port ***list)
48a4076f AJ	191	{
48a4076f AJ	192	char name[PATH_MAX], target[PATH_MAX];
df3b70a8	193	struct dirent *entry;
f1c916ed	194	#ifdef HAVE_STRUCT_SERIAL_STRUCT
48a4076f	195	struct serial_struct serial_info;
12056e2f MC	196	int ioctl_result;
12056e2f MC	197	#endif
df3b70a8	198	char buf[sizeof(entry->d_name) + 23];
12056e2f	199	int len, fd;
48a4076f AJ	200	DIR *dir;
48a4076f AJ	201	int ret = SP_OK;
46d8b0a0	202	struct stat statbuf;
48a4076f AJ	203
	204	DEBUG("Enumerating tty devices");
	205	if (!(dir = opendir("/sys/class/tty")))
dc422c04	206	RETURN_FAIL("Could not open /sys/class/tty");
48a4076f AJ	207
48a4076f AJ	208	DEBUG("Iterating over results");
df3b70a8 AJ	209	while ((entry = readdir(dir))) {
df3b70a8 AJ	210	snprintf(buf, sizeof(buf), "/sys/class/tty/%s", entry->d_name);
46d8b0a0	211	if (lstat(buf, &statbuf) == -1)
	212	continue;
	213	if (!S_ISLNK(statbuf.st_mode))
df3b70a8	214	snprintf(buf, sizeof(buf), "/sys/class/tty/%s/device", entry->d_name);
5bd33b7c	215	len = readlink(buf, target, sizeof(target));
dc422c04	216	if (len <= 0 \|\| len >= (int)(sizeof(target) - 1))
48a4076f AJ	217	continue;
	218	target[len] = 0;
	219	if (strstr(target, "virtual"))
	220	continue;
df3b70a8	221	snprintf(name, sizeof(name), "/dev/%s", entry->d_name);
7890cef6	222	DEBUG_FMT("Found device %s", name);
48a4076f	223	if (strstr(target, "serial8250")) {
dc422c04 UH	224	/*
dc422c04 UH	225	* The serial8250 driver has a hardcoded number of ports.
48a4076f	226	* The only way to tell which actually exist on a given system
dc422c04 UH	227	* is to try to open them and make an ioctl call.
dc422c04 UH	228	*/
48a4076f	229	DEBUG("serial8250 device, attempting to open");
fa106ef1	230	if ((fd = open(name, O_RDWR \| O_NONBLOCK \| O_NOCTTY \| O_CLOEXEC)) < 0) {
dc422c04	231	DEBUG("Open failed, skipping");
48a4076f AJ	232	continue;
48a4076f AJ	233	}
f1c916ed	234	#ifdef HAVE_STRUCT_SERIAL_STRUCT
48a4076f	235	ioctl_result = ioctl(fd, TIOCGSERIAL, &serial_info);
12056e2f	236	#endif
48a4076f	237	close(fd);
f1c916ed	238	#ifdef HAVE_STRUCT_SERIAL_STRUCT
48a4076f AJ	239	if (ioctl_result != 0) {
	240	DEBUG("ioctl failed, skipping");
	241	continue;
	242	}
	243	if (serial_info.type == PORT_UNKNOWN) {
dc422c04	244	DEBUG("Port type is unknown, skipping");
48a4076f AJ	245	continue;
48a4076f AJ	246	}
12056e2f	247	#endif
48a4076f	248	}
7890cef6	249	DEBUG_FMT("Found port %s", name);
48a4076f	250	list = list_append(list, name);
0c3f38b8	251	if (!*list) {
dc422c04	252	SET_ERROR(ret, SP_ERR_MEM, "List append failed");
48a4076f AJ	253	break;
	254	}
	255	}
	256	closedir(dir);
	257
	258	return ret;
	259	}