Remove the udev dependency and parse the /sys hierarchy instead.

diff --git a/README b/README
index 87de434b79dd693c655e7d468e8fb5f8fa07d966..f681f5711cb4faae8fe64da102df7d53a917e157 100644 (file)
--- a/README
+++ b/README
@@ -40,11 +40,7 @@ port, e.g. for USB devices the USB VID and PID of the underlying device.
 Dependencies
 ============
 
-On Linux, libudev is required. On other systems no other libraries are required.
-
-The libudev dependency could be eliminated in favour of direct sysfs queries at
-the cost of some brevity. This is not currently a priority but if you feel like
-doing this feel free to submit a patch.
+No other libraries are required.
 
 Building
 ========

diff --git a/configure.ac b/configure.ac
index 70dd1063f9783c8c1848d0bd96a1d99a639b6348..3ad9bed42a1f946d8aa17fe9e6328f1eeeec13af 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -80,15 +80,6 @@ SP_PKGLIBS=""
 case $target_os in
 *linux*)
        AM_CONDITIONAL([LINUX], true)
-       # On Linux libudev is currently required for enumeration.
-       AC_ARG_WITH([libudev],
-            [AS_HELP_STRING([--with-libudev],
-            [use libudev for serial port enumeration @<:@default=check@:>@])],
-            [], [with_libudev=check])
-       AS_IF([test "x$with_libudev" != xno], [
-       PKG_CHECK_MODULES([libudev], [libudev >= 0],
-               [CFLAGS="$CFLAGS $libudev_CFLAGS"; LIBS="$LIBS $libudev_LIBS";
-               SP_PKGLIBS="$SP_PKGLIBS libudev"; AC_DEFINE(HAVE_LIBUDEV)])], [])
        ;;
 *darwin*)
        AM_CONDITIONAL([LINUX], false)

diff --git a/serialport.c b/serialport.c
index 3d15106d585f5ec843a249fc289a9e2c0dcf321a..056934c7c7eac995faceadd07eeaf45314d4c0b5 100644 (file)
--- a/serialport.c
+++ b/serialport.c
@@ -47,9 +47,7 @@
 #include <sys/syslimits.h>
 #endif
 #ifdef __linux__
-#ifdef HAVE_LIBUDEV
-#include "libudev.h"
-#endif
+#include <dirent.h>
 #ifndef __ANDROID__
 #include "linux/serial.h"
 #endif
@@ -463,72 +461,57 @@ out:
        IOObjectRelease(iter);
 out_done:
 #endif
-#if defined(__linux__) && defined(HAVE_LIBUDEV)
-       struct udev *ud;
-       struct udev_enumerate *ud_enumerate;
-       struct udev_list_entry *ud_list;
-       struct udev_list_entry *ud_entry;
-       const char *path;
-       struct udev_device *ud_dev, *ud_parent;
-       const char *name;
-       const char *driver;
-       int fd, ioctl_result;
+#ifdef __linux__
+       char name[PATH_MAX], target[PATH_MAX];
+       struct dirent entry, *result;
        struct serial_struct serial_info;
+       int len, fd, ioctl_result;
+       DIR *dir;
 
        ret = SP_OK;
 
        DEBUG("Enumerating tty devices");
-       ud = udev_new();
-       ud_enumerate = udev_enumerate_new(ud);
-       udev_enumerate_add_match_subsystem(ud_enumerate, "tty");
-       udev_enumerate_scan_devices(ud_enumerate);
-       ud_list = udev_enumerate_get_list_entry(ud_enumerate);
+       if (!(dir = opendir("/sys/class/tty")))
+               RETURN_FAIL("could not open /sys/class/tty");
+
        DEBUG("Iterating over results");
-       udev_list_entry_foreach(ud_entry, ud_list) {
-               path = udev_list_entry_get_name(ud_entry);
-               DEBUG("Found device %s", path);
-               ud_dev = udev_device_new_from_syspath(ud, path);
-               /* If there is no parent device, this is a virtual tty. */
-               ud_parent = udev_device_get_parent(ud_dev);
-               if (ud_parent == NULL) {
-                       DEBUG("No parent device, assuming virtual tty");
-                       udev_device_unref(ud_dev);
+       while (!readdir_r(dir, &entry, &result) && result) {
+               len = readlinkat(dirfd(dir), entry.d_name, target, sizeof(target));
+               if (len <= 0 || len >= (int) sizeof(target)-1)
                        continue;
-               }
-               name = udev_device_get_devnode(ud_dev);
-               /* 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. */
-               driver = udev_device_get_driver(ud_parent);
-               if (driver && !strcmp(driver, "serial8250")) {
+               target[len] = 0;
+               if (strstr(target, "virtual"))
+                       continue;
+               snprintf(name, sizeof(name), "/dev/%s", entry.d_name);
+               DEBUG("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");
-                               goto skip;
+                               continue;
                        }
                        ioctl_result = ioctl(fd, TIOCGSERIAL, &serial_info);
                        close(fd);
                        if (ioctl_result != 0) {
                                DEBUG("ioctl failed, skipping");
-                               goto skip;
+                               continue;
                        }
                        if (serial_info.type == PORT_UNKNOWN) {
                                DEBUG("port type is unknown, skipping");
-                               goto skip;
+                               continue;
                        }
                }
                DEBUG("Found port %s", name);
                list = list_append(list, name);
-skip:
-               udev_device_unref(ud_dev);
                if (!list) {
                        SET_ERROR(ret, SP_ERR_MEM, "list append failed");
-                       goto out;
+                       break;
                }
        }
-out:
-       udev_enumerate_unref(ud_enumerate);
-       udev_unref(ud);
+       closedir(dir);
 #endif
 
        switch (ret) {