libserialport/linux.c

228 lines
6.6 KiB
C

/*
* This file is part of the libserialport project.
*
* 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 "libserialport.h"
#include "libserialport_internal.h"
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, vid, pid = -1;
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] = "", file_name[PATH_MAX];
char *ptr, *dev = port->name + 5;
FILE *file;
int i, count;
if (strncmp(port->name, "/dev/", 5))
RETURN_ERROR(SP_ERR_ARG, "Device name not recognized.");
snprintf(file_name, sizeof(file_name), "/sys/class/tty/%s", dev);
count = readlink(file_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(file_name, "r")))
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(file_name, "r")))
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(file_name, "r")))
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(file_name, "r")))
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(file_name, "r"))) {
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(file_name, "r"))) {
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(file_name, "r"))) {
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(file_name, "r"))) {
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);
}
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(file_name, "r"))) {
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, *result;
#ifdef HAVE_SERIAL_STRUCT
struct serial_struct serial_info;
int ioctl_result;
#endif
#ifndef HAVE_READLINKAT
char buf[sizeof(entry.d_name) + 16];
#endif
int len, fd;
DIR *dir;
int ret = SP_OK;
DEBUG("Enumerating tty devices");
if (!(dir = opendir("/sys/class/tty")))
RETURN_FAIL("could not open /sys/class/tty");
DEBUG("Iterating over results");
while (!readdir_r(dir, &entry, &result) && result) {
#ifdef HAVE_READLINKAT
len = readlinkat(dirfd(dir), entry.d_name, target, sizeof(target));
#else
snprintf(buf, sizeof(buf), "/sys/class/tty/%s", entry.d_name);
len = readlink(buf, target, sizeof(target));
#endif
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)) < 0) {
DEBUG("open failed, skipping");
continue;
}
#ifdef HAVE_SERIAL_STRUCT
ioctl_result = ioctl(fd, TIOCGSERIAL, &serial_info);
#endif
close(fd);
#ifdef HAVE_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;
}