#include <stdlib.h>
#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+
#include "udev.h"
#include "udev_version.h"
}
-/* yeah this should be dynamically allocated... */
-static char device[255];
-
static char *get_device(void)
{
+ static char device[255];
char *temp;
temp = getenv("DEVPATH");
return device;
}
+/*
+ * Right now the major/minor of a device is stored in a file called
+ * "dev" in sysfs.
+ * The number is stored as:
+ * MMmm
+ * MM is the major
+ * mm is the minor
+ * The value is in hex.
+ * Yes, this will probably change when we go to a bigger major/minor
+ * range, and will have to be changed at that time.
+ */
+static int get_major_minor (char *dev, int *major, int *minor)
+{
+ char filename[255];
+ char line[20];
+ char temp[3];
+ int fd;
+ int retval = 0;
+
+ /* add the dev file to the directory and see if it's present */
+ strncpy(filename, dev, sizeof(filename));
+ strncat(filename, DEV_FILE, sizeof(filename));
+ fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ dbg("Can't open %s", filename);
+ return -ENODEV;
+ }
+
+ /* get the major/minor */
+ retval = read(fd, line, sizeof(line));
+ if (retval < 0) {
+ dbg("read error on %s", dev);
+ goto exit;
+ }
+
+ temp[0] = line[0];
+ temp[1] = line[1];
+ temp[2] = 0x00;
+ *major = (int)strtol(&temp[0], NULL, 16);
+
+ temp[0] = line[2];
+ temp[1] = line[3];
+ temp[2] = 0x00;
+ *minor = (int)strtol(&temp[0], NULL, 16);
+
+ dbg("found major = %d, minor = %d", *major, *minor);
+
+ retval = 0;
+exit:
+ close(fd);
+ return retval;
+}
+
+/*
+ * Here would go a call to the naming deamon, to get the name we want to have
+ * for this device. But for now, let's just default to whatever the kernel is
+ * calling the device as that will keep the "old-style" naming policy
+ */
+static char *get_name(char *dev, int major, int minor)
+{
+ static char name[100];
+ char *temp;
+
+ temp = strrchr(dev, '/');
+ if (temp == NULL)
+ return NULL;
+ strncpy(name, &temp[1], sizeof(name));
+
+ dbg("name is %s", name);
+
+ return &name[0];
+}
+
+/*
+ * Again, this will live in the naming deamon
+ */
+static int get_mode(char *name, char *dev, int major, int minor)
+{
+ /* just default everyone to rw for the world! */
+ return 0666;
+}
+
+/*
+ * We also want to add some permissions here, and possibly some symlinks
+ */
+static int create_node(char *name, char type, int major, int minor, int mode)
+{
+ char *argv[7];
+ char mode_string[100];
+ char type_string[3];
+ char major_string[20];
+ char minor_string[20];
+ char filename[255];
+ int retval = 0;
+
+ strncpy(filename, UDEV_ROOT, sizeof(filename));
+ strncat(filename, name, sizeof(filename));
+
+ snprintf(mode_string, sizeof(mode_string), "--mode=%#o", mode);
+ snprintf(type_string, sizeof(type_string), "%c", type);
+ snprintf(major_string, sizeof(major_string), "%d", major);
+ snprintf(minor_string, sizeof(minor_string), "%d", minor);
+
+ argv[0] = MKNOD;
+ argv[1] = mode_string;
+ argv[2] = filename;
+ argv[3] = type_string;
+ argv[4] = major_string;
+ argv[5] = minor_string;
+ argv[6] = NULL;
+ dbg ("executing %s %s %s %s %s %s",
+ argv[0], argv[1], argv[2], argv[3], argv[4], argv[5]);
+ switch (fork()) {
+ case 0:
+ /* we are the child, so lets run the program */
+ execv (MKNOD, argv);
+ exit(0);
+ break;
+ case (-1):
+ dbg ("fork failed.");
+ retval = -EFAULT;
+ break;
+ default:
+ break;
+ }
+ return retval;
+}
+
+/*
+ * We also want to clean up any symlinks that were created in create_node()
+ */
+static int delete_node(char *name)
+{
+ char filename[255];
+
+ strncpy(filename, UDEV_ROOT, sizeof(filename));
+ strncat(filename, name, sizeof(filename));
+
+ dbg("unlinking %s", filename);
+ return unlink(filename);
+}
+
+static int add_device(char *device, char type)
+{
+ char *name;
+ int major;
+ int minor;
+ int mode;
+ int retval = -EINVAL;
+
+ retval = get_major_minor(device, &major, &minor);
+ if (retval) {
+ dbg ("get_major_minor failed");
+ goto exit;
+ }
+
+ name = get_name(device, major, minor);
+ if (name == NULL) {
+ dbg ("get_name failed");
+ retval = -ENODEV;
+ goto exit;
+ }
+
+ mode = get_mode(name, device, major, minor);
+ if (mode < 0) {
+ dbg ("get_mode failed");
+ retval = -EINVAL;
+ goto exit;
+ }
+
+ return create_node(name, type, major, minor, mode);
+
+exit:
+ return retval;
+}
+
+static int remove_device(char *device)
+{
+ char *name;
+ int retval = 0;
+
+ name = get_name(device, 0, 0);
+ if (name == NULL) {
+ dbg ("get_name failed");
+ retval = -ENODEV;
+ goto exit;
+ }
+
+ return delete_node(name);
+
+exit:
+ return retval;
+}
int main(int argc, char *argv[])
{
char *subsystem;
char *action;
- char *dev;
+ char *device;
+ char type;
+ int retval = -EINVAL;
if (argc != 2) {
dbg ("unknown number of arguments");
- return 1;
+ goto exit;
}
+ /* for now, the block layer is the only place where block devices are */
subsystem = argv[1];
+ if (strcmp(subsystem, "block") == 0)
+ type = 'b';
+ else
+ type = 'c';
action = get_action();
if (!action) {
dbg ("no action?");
- return 1;
+ goto exit;
}
- dev = get_device();
- if (!dev) {
+ device = get_device();
+ if (!device) {
dbg ("no device?");
- return 1;
+ goto exit;
}
+ dbg("looking at %s", device);
+
+ if (strcmp(action, "add") == 0)
+ return add_device(device, type);
+
+ if (strcmp(action, "remove") == 0)
+ return remove_device(device);
+
+ dbg("Unknown action: %s", action);
+ return -EINVAL;
- return 0;
+ retval = 0;
+exit:
+ return retval;
}
~ianmdlvl / elogind.git / blobdiff