X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=libsysfs%2Fsysfs_class.c;h=db59aef90f60ce61ee2bf086e076a4f07e40c180;hb=6818c51d7abeab9914eb7193968b1efa9459a853;hp=16eaf6e51468429136a30d7072919e5a50c6882c;hpb=bcbe2d8e7d4ccd975e79d0c7defbe1d64d1b129c;p=elogind.git

diff --git a/libsysfs/sysfs_class.c b/libsysfs/sysfs_class.c
index 16eaf6e51..db59aef90 100644
--- a/libsysfs/sysfs_class.c
+++ b/libsysfs/sysfs_class.c
@@ -38,8 +38,7 @@ static int class_name_equal(void *a, void *b)
 	if (a == NULL || b == NULL)
 		return 0;
 
-	if (strcmp(((unsigned char *)a), ((struct sysfs_class_device *)b)->name)
-		== 0)
+	if (strcmp(((char *)a), ((struct sysfs_class_device *)b)->name) == 0)
 		return 1;
 
 	return 0;
@@ -66,7 +65,7 @@ void sysfs_close_class_device(struct sysfs_class_device *dev)
 
 /**
  * sysfs_close_class: close single class
- * @class: class structure
+ * @cls: class structure
  */
 void sysfs_close_class(struct sysfs_class *cls)
 {
@@ -105,7 +104,7 @@ static struct sysfs_class *alloc_class(void)
  */
 static void set_classdev_classname(struct sysfs_class_device *cdev)
 {
-	unsigned char *c = NULL, *e = NULL;
+	char *c = NULL, *e = NULL;
 	int count = 0;
 
 	c = strstr(cdev->path, SYSFS_CLASS_NAME);
@@ -116,7 +115,7 @@ static void set_classdev_classname(struct sysfs_class_device *cdev)
 	}
 
 	if (c == NULL)
-		strcpy(cdev->classname, SYSFS_UNKNOWN);
+		safestrcpy(cdev->classname, SYSFS_UNKNOWN);
 	else {
 		if (*c == '/')
 			c++;
@@ -134,8 +133,7 @@ static void set_classdev_classname(struct sysfs_class_device *cdev)
  * @path: path to class device.
  * returns struct sysfs_class_device with success and NULL with error.
  */
-struct sysfs_class_device *sysfs_open_class_device_path
-					(const unsigned char *path)
+struct sysfs_class_device *sysfs_open_class_device_path(const char *path)
 {
 	struct sysfs_class_device *cdev = NULL;
 
@@ -159,7 +157,12 @@ struct sysfs_class_device *sysfs_open_class_device_path
 		return NULL;
 	}
 
-	strcpy(cdev->path, path);
+	safestrcpy(cdev->path, path);
+	if ((sysfs_remove_trailing_slash(cdev->path)) != 0) {
+		dprintf("Invalid path to class device %s\n", cdev->path);
+		sysfs_close_class_device(cdev);
+		return NULL;
+	}
 	set_classdev_classname(cdev);
 
 	return cdev;
@@ -167,7 +170,7 @@ struct sysfs_class_device *sysfs_open_class_device_path
 
 /**
  * sysfs_get_class_devices: gets all devices for class
- * @class: class to get devices for
+ * @cls: class to get devices for
  * returns dlist of class_devices with success and NULL with error
  */
 struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
@@ -179,6 +182,10 @@ struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
 		errno = EINVAL;
 		return NULL;
 	}
+
+	if (cls->devices != NULL) 
+		return cls->devices;
+
 	if (cls->directory == NULL) {
 		cls->directory = sysfs_open_directory(cls->path);
 		if (cls->directory == NULL) 
@@ -201,7 +208,7 @@ struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
 				cls->devices = dlist_new_with_delete
 					(sizeof(struct sysfs_class_device),
 					 		sysfs_close_cls_dev);
-			dlist_unshift(cls->devices, dev);
+			dlist_unshift_sorted(cls->devices, dev, sort_list);
 		}
 	}
 	return cls->devices;
@@ -211,10 +218,10 @@ struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
  * sysfs_open_class: opens specific class and all its devices on system
  * returns sysfs_class structure with success or NULL with error.
  */
-struct sysfs_class *sysfs_open_class(const unsigned char *name)
+struct sysfs_class *sysfs_open_class(const char *name)
 {
 	struct sysfs_class *cls = NULL;
-	unsigned char classpath[SYSFS_PATH_MAX];
+	char classpath[SYSFS_PATH_MAX];
 
 	if (name == NULL) {
 		errno = EINVAL;
@@ -226,19 +233,19 @@ struct sysfs_class *sysfs_open_class(const unsigned char *name)
                 dprintf("Sysfs not supported on this system\n");
                 return NULL;
         }
-	if (sysfs_trailing_slash(classpath) == 0)
-		strcat(classpath, "/");
 
 	/* 
 	 * We shall now treat "block" also as a class. Hence, check here
 	 * if "name" is "block" and proceed accordingly
 	 */
 	if (strcmp(name, SYSFS_BLOCK_NAME) == 0) {
-		strcat(classpath, SYSFS_BLOCK_NAME);
+		safestrcat(classpath, "/");
+		safestrcat(classpath, SYSFS_BLOCK_NAME);
 	} else {
-		strcat(classpath, SYSFS_CLASS_NAME);
-		strcat(classpath, "/");
-		strcat(classpath, name);
+		safestrcat(classpath, "/");
+		safestrcat(classpath, SYSFS_CLASS_NAME);
+		safestrcat(classpath, "/");
+		safestrcat(classpath, name);
 	}
 	if ((sysfs_path_is_dir(classpath)) != 0) {
 		dprintf("Class %s not found on the system\n", name);
@@ -250,8 +257,13 @@ struct sysfs_class *sysfs_open_class(const unsigned char *name)
 		dprintf("calloc failed\n");
 		return NULL;
 	}
-	strcpy(cls->name, name);	
-	strcpy(cls->path, classpath);
+	safestrcpy(cls->name, name);	
+	safestrcpy(cls->path, classpath);
+	if ((sysfs_remove_trailing_slash(cls->path)) != 0) {
+		dprintf("Invalid path to class device %s\n", cls->path);
+		sysfs_close_class(cls);
+		return NULL;
+	}
 	
 	return cls;
 }
@@ -261,22 +273,20 @@ struct sysfs_class *sysfs_open_class(const unsigned char *name)
  * @class: class to find device on
  * @name: class name of the device
  */ 
-struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *class,
-					unsigned char *name)
+struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *cls,
+					char *name)
 {
-	struct dlist *devlist = NULL;
-	
-	if (class == NULL || name == NULL) {
+	if (cls == NULL || name == NULL) {
 		errno = EINVAL;
 		return NULL;
 	}
 
-	if (class->devices == NULL) {
-		class->devices = sysfs_get_class_devices(class);
-		if (devlist == NULL) 
+	if (cls->devices == NULL) {
+		cls->devices = sysfs_get_class_devices(cls);
+		if (cls->devices == NULL) 
 			return NULL;
 	}
-	return (struct sysfs_class_device *)dlist_find_custom(class->devices,
+	return (struct sysfs_class_device *)dlist_find_custom(cls->devices,
 			name, class_name_equal);
 }
 
@@ -291,14 +301,21 @@ struct sysfs_device *sysfs_get_classdev_device
 			(struct sysfs_class_device *clsdev)
 {
 	struct sysfs_link *devlink = NULL;
+	char devpath[SYSFS_PATH_MAX];
 	
 	if (clsdev == NULL) {
 		errno = EINVAL;
 		return NULL;
 	}
-	
-	if (clsdev->sysdevice != NULL)
-		return (clsdev->sysdevice);
+	safestrcpy(devpath, clsdev->path);
+	safestrcat(devpath, "/device");
+	if ((sysfs_path_is_link(devpath)) != 0) {
+		if (clsdev->sysdevice != NULL) {
+			sysfs_close_device(clsdev->sysdevice);
+			clsdev->sysdevice = NULL;
+		}
+		return NULL;
+	}
 	
 	if (clsdev->directory == NULL) {
 		clsdev->directory = sysfs_open_directory(clsdev->path);
@@ -306,14 +323,28 @@ struct sysfs_device *sysfs_get_classdev_device
 			return NULL;
 	}
 	devlink = sysfs_get_directory_link(clsdev->directory, "device");
-	if (devlink == NULL) 
+	if (devlink == NULL) {
+		if (clsdev->sysdevice != NULL) {
+			dprintf("Device link no longer exists\n");
+			sysfs_close_device(clsdev->sysdevice);
+			clsdev->sysdevice = NULL;
+		}
 		return NULL;
+	}
+
+	if (clsdev->sysdevice != NULL) {
+		if (!strncmp(devlink->target, clsdev->sysdevice->path,
+						SYSFS_PATH_MAX)) 
+			/* sysdevice hasn't changed */
+			return (clsdev->sysdevice);
+		else 
+			/* come here only if the device link for has changed */
+			sysfs_close_device(clsdev->sysdevice);
+	}
 
 	clsdev->sysdevice = sysfs_open_device_path(devlink->target);
 	if (clsdev->sysdevice == NULL)
 		return NULL;
-	if (clsdev->driver != NULL) 
-		strcpy(clsdev->sysdevice->driver_name, clsdev->driver->name);
 
 	return (clsdev->sysdevice);
 }
@@ -329,31 +360,54 @@ struct sysfs_driver *sysfs_get_classdev_driver
 			(struct sysfs_class_device *clsdev)
 {
 	struct sysfs_link *drvlink = NULL;
+	char drvpath[SYSFS_PATH_MAX];
 	
 	if (clsdev == NULL) {
 		errno = EINVAL;
 		return NULL;
 	}
-	
-	if (clsdev->driver != NULL)
-		return (clsdev->driver);
-	
+ 	safestrcpy(drvpath, clsdev->path);
+	safestrcat(drvpath, "/driver");
+	if ((sysfs_path_is_link(drvpath)) != 0) {
+		if (clsdev->driver != NULL) {
+			sysfs_close_driver(clsdev->driver);
+			clsdev->driver = NULL;
+		}
+		return NULL;
+	}
+	 
 	if (clsdev->directory == NULL) {
 		clsdev->directory = sysfs_open_directory(clsdev->path);
 		if (clsdev->directory == NULL)
 			return NULL;
 	}
 	drvlink = sysfs_get_directory_link(clsdev->directory, "driver");
-	if (drvlink != NULL) {
-		clsdev->driver = sysfs_open_driver_path(drvlink->target);
-		if (clsdev->driver == NULL)
-			return NULL;
-			
+	if (drvlink == NULL) {
+		if (clsdev->driver != NULL) {
+			dprintf("Driver link no longer exists\n");
+			sysfs_close_driver(clsdev->driver);
+			clsdev->driver = NULL;
+		}
+		return NULL;
+	}
+	if (clsdev->driver != NULL) {
+		if (!strncmp(drvlink->target, clsdev->driver->path,
+	      						SYSFS_PATH_MAX))
+			/* driver hasn't changed */
+	 		return (clsdev->driver);
+ 		else
+			/* come here only if the device link for has changed */
+			sysfs_close_driver(clsdev->driver);
 	}
+		
+	clsdev->driver = sysfs_open_driver_path(drvlink->target);
+	if (clsdev->driver == NULL)
+		return NULL;
+
 	return (clsdev->driver);
 }
-	
-/* 
+
+/** 
  * get_blockdev_parent: Get the parent class device for a "block" subsystem 
  * 		device if present
  * @clsdev: block subsystem class device whose parent needs to be found
@@ -361,48 +415,33 @@ struct sysfs_driver *sysfs_get_classdev_driver
  */
 static int get_blockdev_parent(struct sysfs_class_device *clsdev)
 {
-	unsigned char parent_path[SYSFS_PATH_MAX], value[256], *c = NULL;
-	
-	memset(parent_path, 0, SYSFS_PATH_MAX);
-	strcpy(parent_path, clsdev->path);
+	char parent_path[SYSFS_PATH_MAX], *c = NULL;
 
+	safestrcpy(parent_path, clsdev->path);
 	c = strstr(parent_path, SYSFS_BLOCK_NAME);
 	if (c == NULL) {
-		dprintf("Class device %s does not belong to BLOCK subsystem",
+		dprintf("Class device %s does not belong to BLOCK subsystem\n",
 				clsdev->name);
 		return 1;
 	}
-	
 	c += strlen(SYSFS_BLOCK_NAME);
 	if (*c == '/')
 		c++;
 	else
 		goto errout;
-	
-	/* validate whether the given class device is a partition or not */ 
-	if ((strncmp(c, clsdev->name, strlen(clsdev->name))) == 0) {
-		dprintf("%s not a partition\n", clsdev->name);
-		return 1;
-	}
-	c = strchr(c, '/');
-	if (c == NULL) 
-		goto errout;
-	*c = '\0';
-	
-	/* Now validate if the parent has the "dev" attribute */
-	memset(value, 0, 256);
-	strcat(parent_path, "/dev");
-	if ((sysfs_read_attribute_value(parent_path, value, 256)) != 0) {
-		dprintf("Block device %s does not have a parent\n", 
-							clsdev->name);
-		return 1;
-	}
-		
-	c = strrchr(parent_path, '/');
+
+       /* validate whether the given class device is a partition or not */
+        if ((strncmp(c, clsdev->name, strlen(clsdev->name))) == 0) {
+                dprintf("%s not a partition\n", clsdev->name);
+                return 1;
+        }
+		      
+      	c = strchr(c, '/');
 	if (c == NULL)
 		goto errout;
 
 	*c = '\0';
+					
 	clsdev->parent = sysfs_open_class_device_path(parent_path);
 	if (clsdev->parent == NULL) {
 		dprintf("Error opening the parent class device at %s\n", 
@@ -440,7 +479,8 @@ struct sysfs_class_device *sysfs_get_classdev_parent
 	 * structure. Hence, we now call a specialized function for block and
 	 * later we can add support functions for other subsystems as required.
 	 */ 
-	if (!(strcmp(clsdev->classname, SYSFS_BLOCK_NAME))) {
+	if (!(strncmp(clsdev->classname, SYSFS_BLOCK_NAME, 
+					sizeof(SYSFS_BLOCK_NAME)))) {
 		if ((get_blockdev_parent(clsdev)) == 0) 
 			return (clsdev->parent);
 	}
@@ -456,8 +496,8 @@ struct sysfs_class_device *sysfs_get_classdev_parent
  * @psize: size of "path"
  * Returns 0 on SUCCESS or -1 on error
  */
-static int get_classdev_path(const unsigned char *classname, 
-		const unsigned char *clsdev, unsigned char *path, size_t len)
+static int get_classdev_path(const char *classname, const char *clsdev, 
+		char *path, size_t len)
 {
 	if (classname == NULL || clsdev == NULL || path == NULL) {
 		errno = EINVAL;
@@ -467,19 +507,18 @@ static int get_classdev_path(const unsigned char *classname,
                 dprintf("Error getting sysfs mount path\n");
                 return -1;
 	}
-
-	if (sysfs_trailing_slash(path) == 0)
-		strcat(path, "/");
-
-	if (strcmp(classname, SYSFS_BLOCK_NAME) == 0) {
-		strcat(path, SYSFS_BLOCK_NAME);
+	if (strncmp(classname, SYSFS_BLOCK_NAME,
+				sizeof(SYSFS_BLOCK_NAME)) == 0) {
+		safestrcatmax(path, "/", len);
+		safestrcatmax(path, SYSFS_BLOCK_NAME, len);
 	} else {
-		strcat(path, SYSFS_CLASS_NAME);
-		strcat(path, "/");
-		strcat(path, classname);
+		safestrcatmax(path, "/", len);
+		safestrcatmax(path, SYSFS_CLASS_NAME, len);
+		safestrcatmax(path, "/", len);
+		safestrcatmax(path, classname, len);
 	}
-	strcat(path, "/");
-	strcat(path, clsdev);
+	safestrcatmax(path, "/", len);
+	safestrcatmax(path, clsdev, len);
 	return 0;
 }
 
@@ -493,9 +532,9 @@ static int get_classdev_path(const unsigned char *classname,
  * 	Call sysfs_close_class_device() to close the class device
  */
 struct sysfs_class_device *sysfs_open_class_device
-		(const unsigned char *classname, const unsigned char *name)
+		(const char *classname, const char *name)
 {
-	unsigned char devpath[SYSFS_PATH_MAX];
+	char devpath[SYSFS_PATH_MAX];
 	struct sysfs_class_device *cdev = NULL;
 
 	if (classname == NULL || name == NULL) {
@@ -537,26 +576,40 @@ struct dlist *sysfs_get_classdev_attributes(struct sysfs_class_device *cdev)
 			return NULL;
 	}
 	if (cdev->directory->attributes == NULL) {
-		if ((sysfs_read_dir_attributes(cdev->directory)) != 0) {
-			dprintf("Error reading attributes for directory %s\n",
-							cdev->directory->path);
+		if ((sysfs_read_dir_attributes(cdev->directory)) != 0) 
 			return NULL;
-		}
-	} else {
-		if ((sysfs_path_is_dir(cdev->path)) != 0) {
-			dprintf("Class device at %s no longer exists\n", 
-							cdev->path);
-			return NULL;
-		}
-		if ((sysfs_refresh_attributes
-					(cdev->directory->attributes)) != 0) {
-			dprintf("Error refreshing classdev attributes\n");
-			return NULL;
-		}
 	}
 	return (cdev->directory->attributes);
 }
 
+/**
+ * sysfs_refresh_clsassdev_attributes: refreshes the driver's list of attributes
+ * @clsdev: sysfs_class_device whose attributes to refresh
+ *
+ * NOTE: Upon return, prior references to sysfs_attributes for this classdev
+ *              _may_ not be valid
+ *
+ * Returns list of attributes on success and NULL on failure
+ */
+struct dlist *sysfs_refresh_classdev_attributes
+			(struct sysfs_class_device *clsdev)
+{
+	if (clsdev == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (clsdev->directory == NULL)
+		return (sysfs_get_classdev_attributes(clsdev));
+
+	if ((sysfs_refresh_dir_attributes(clsdev->directory)) != 0) {
+		dprintf("Error refreshing class_device attributes\n");
+		return NULL;
+	}
+
+	return (clsdev->directory->attributes);
+}
+
 /**
  * sysfs_get_classdev_attr: searches class device's attributes by name
  * @clsdev: class device to look through
@@ -564,7 +617,7 @@ struct dlist *sysfs_get_classdev_attributes(struct sysfs_class_device *cdev)
  * returns sysfs_attribute reference with success or NULL with error
  */
 struct sysfs_attribute *sysfs_get_classdev_attr
-		(struct sysfs_class_device *clsdev, const unsigned char *name)
+		(struct sysfs_class_device *clsdev, const char *name)
 {
 	struct sysfs_attribute *cur = NULL;
 	struct sysfs_directory *sdir = NULL;
@@ -582,7 +635,7 @@ struct sysfs_attribute *sysfs_get_classdev_attr
 	attrlist = sysfs_get_classdev_attributes(clsdev);
 	if (attrlist != NULL) {
 		cur = sysfs_get_directory_attribute(clsdev->directory,
-						(unsigned char *)name);
+						(char *)name);
 		if (cur != NULL)
 			return cur;
 	}
@@ -597,15 +650,10 @@ struct sysfs_attribute *sysfs_get_classdev_attr
 						struct sysfs_directory) {
 			if ((sysfs_path_is_dir(sdir->path)) != 0) 
 				continue;
-			if (sdir->attributes == NULL) {
-				cur = sysfs_get_directory_attribute(sdir,
-							(unsigned char *)name);
-			} else {
-				if ((sysfs_refresh_attributes
-						(sdir->attributes)) == 0)
-				cur = sysfs_get_directory_attribute(sdir, 
-							(unsigned char *)name);
-			}
+			cur = sysfs_get_directory_attribute(sdir,
+							(char *)name);
+			if (cur == NULL)
+				continue;
 		}
 	}
 	return cur;
@@ -622,11 +670,11 @@ struct sysfs_attribute *sysfs_get_classdev_attr
  * 	A call to sysfs_close_attribute() is required to close the
  * 	attribute returned and to free memory
  */
-struct sysfs_attribute *sysfs_open_classdev_attr(const unsigned char *classname,
-		const unsigned char *dev, const unsigned char *attrib)
+struct sysfs_attribute *sysfs_open_classdev_attr(const char *classname,
+		const char *dev, const char *attrib)
 {
 	struct sysfs_attribute *attribute = NULL;
-	unsigned char path[SYSFS_PATH_MAX];
+	char path[SYSFS_PATH_MAX];
 
 	if (classname == NULL || dev == NULL || attrib == NULL) {
 		errno = EINVAL;
@@ -638,8 +686,8 @@ struct sysfs_attribute *sysfs_open_classdev_attr(const unsigned char *classname,
 						dev, classname);
 		return NULL;
 	}
-	strcat(path, "/");
-	strcat(path, attrib);
+	safestrcat(path, "/");
+	safestrcat(path, attrib);
 	attribute = sysfs_open_attribute(path);
 	if (attribute == NULL) {
 		dprintf("Error opening attribute %s on class device %s\n",