X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udev.c;h=b3e18ff9daec621fb87d89486e54d0fce04af6ab;hp=1ac1c985076be16e6d1eab73fdd65d7b58cb7d33;hb=19dc5d4ce15ad387031ec4e78dc615a9eb07dc08;hpb=f0083e3d4eb49e11fd7e37532dc64a6e6f5d4039 diff --git a/udev.c b/udev.c index 1ac1c9850..b3e18ff9d 100644 --- a/udev.c +++ b/udev.c @@ -23,9 +23,18 @@ #include #include +#include +#include +#include +#include + #include "udev.h" #include "udev_version.h" +#include "namedev.h" +#include "libsysfs/libsysfs.h" + +static char sysfs_path[SYSFS_PATH_MAX]; static char *get_action(void) { @@ -36,48 +45,271 @@ static char *get_action(void) } -/* yeah this should be dynamically allocated... */ -static char device[255]; - static char *get_device(void) { + char *device; + + device = 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(struct sysfs_class_device *class_dev, int *major, int *minor) +{ + char temp[3]; + int retval = 0; + + char *dev; + + dev = sysfs_get_value_from_attributes(class_dev->directory->attributes, "dev"); + if (dev == NULL) + return -ENODEV; + + dbg("dev = %s", dev); + + temp[0] = dev[0]; + temp[1] = dev[1]; + temp[2] = 0x00; + *major = (int)strtol(&temp[0], NULL, 16); + + temp[0] = dev[2]; + temp[1] = dev[3]; + temp[2] = 0x00; + *minor = (int)strtol(&temp[0], NULL, 16); + + dbg("found major = %d, minor = %d", *major, *minor); + + retval = 0; + 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 = getenv("DEVPATH"); + temp = strrchr(dev, '/'); if (temp == NULL) return NULL; - strcpy(device, SYSFS_ROOT); - strcat(device, temp); + strncpy(name, &temp[1], sizeof(name)); - return device; + dbg("name is %s", name); + + return &name[0]; +} + +/* + * 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); } +struct sysfs_class_device *get_class_dev(char *device_name) +{ + char dev_path[SYSFS_PATH_MAX]; + struct sysfs_class_device *class_dev; + + strcpy(dev_path, sysfs_path); + strcat(dev_path, device_name); + + dbg("looking at %s", dev_path); + + /* open up the sysfs class device for this thing... */ + class_dev = sysfs_open_class_device(dev_path); + if (class_dev == NULL) { + dbg ("sysfs_open_class_device failed"); + return NULL; + } + dbg("class_dev->name = %s", class_dev->name); + + return class_dev; +} + +static int add_device(char *device, char *subsystem) +{ + struct sysfs_class_device *class_dev; + struct device_attr attr; + //char *name; + int major; + int minor; + char type; + //int mode; + int retval = -EINVAL; + + /* for now, the block layer is the only place where block devices are */ + if (strcmp(subsystem, "block") == 0) + type = 'b'; + else + type = 'c'; + + class_dev = get_class_dev(device); + if (class_dev == NULL) + goto exit; + + retval = namedev_name_device(class_dev, &attr); + if (retval) + return retval; + + retval = get_major_minor(class_dev, &major, &minor); + if (retval) { + dbg ("get_major_minor failed"); + goto exit; + } + + sysfs_close_class_device(class_dev); + + return create_node(attr.name, type, major, minor, attr.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; +} + +static int udev_init(void) +{ + int retval; + + retval = sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX); + dbg("sysfs_path = %s", sysfs_path); + return retval; +} int main(int argc, char *argv[]) { - char *subsystem; char *action; - char *dev; + char *device; + int retval = -EINVAL; if (argc != 2) { dbg ("unknown number of arguments"); - return 1; + goto exit; } - subsystem = argv[1]; + device = get_device(); + if (!device) { + dbg ("no device?"); + goto exit; + } + dbg("looking at %s", device); + + /* we only care about class devices and block stuff */ + if (!strstr(device, "class") && + !strstr(device, "block")) { + dbg("not block or class"); + goto exit; + } + + /* sleep for a second or two to give the kernel a chance to + * create the dev file + */ + sleep(1); + + udev_init(); + namedev_init(); action = get_action(); if (!action) { dbg ("no action?"); - return 1; + goto exit; } - dev = get_device(); - if (!dev) { - dbg ("no device?"); - return 1; - } + if (strcmp(action, "add") == 0) + return add_device(device, argv[1]); + + if (strcmp(action, "remove") == 0) + return remove_device(device); + + dbg("Unknown action: %s", action); + return -EINVAL; - return 0; + retval = 0; +exit: + return retval; }