X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=libsysfs%2Fsysfs_utils.c;h=627e618dceaf699dd811e091e09980126d4e711f;hb=a27170c49a777c132e0f0c81dda72c3c064ba4b7;hp=f1303cacb302e2a011cdd45cf6f18f1139e4ec44;hpb=1e959a4b05f93bf31d0603a027b50cb148ef7e90;p=elogind.git

diff --git a/libsysfs/sysfs_utils.c b/libsysfs/sysfs_utils.c
index f1303cacb..627e618dc 100644
--- a/libsysfs/sysfs_utils.c
+++ b/libsysfs/sysfs_utils.c
@@ -76,6 +76,23 @@ static int sysfs_get_fs_mnt_path(const unsigned char *fs_type,
 #endif
 }
 
+/*
+ * sysfs_trailing_slash: checks if there's a trailing slash to path
+ * @path: path to check
+ * returns 1 if true and 0 if not
+ */
+int sysfs_trailing_slash(unsigned char *path)
+{
+	unsigned char *s = NULL;
+
+	if (path == NULL)
+		return 0;
+	s = &path[strlen(path)-1];
+	if (strncmp(s, "/", 1) == 0)
+		return 1;
+	return 0;
+}
+
 /*
  * sysfs_get_mnt_path: Gets the sysfs mount point.
  * @mnt_path: place to put "sysfs" mount point
@@ -84,12 +101,18 @@ static int sysfs_get_fs_mnt_path(const unsigned char *fs_type,
  */
 int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
 {
-	int ret = -1;
+	char *sysfs_path = NULL;
+	int ret = 0;
 
-	if (mnt_path != NULL)
-		ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
-	else
+	if (mnt_path == NULL) {
 		errno = EINVAL;
+		return -1;
+	}
+	sysfs_path = getenv(SYSFS_PATH_ENV);
+	if (sysfs_path != NULL) 
+		strncpy(mnt_path, sysfs_path, len);
+	else
+		ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
 
 	return ret;
 }
@@ -103,13 +126,19 @@ int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
 int sysfs_get_name_from_path(const unsigned char *path, unsigned char *name, 
 								size_t len)
 {
+	unsigned char tmp[SYSFS_PATH_MAX];
 	unsigned char *n = NULL;
                                                                                 
 	if (path == NULL || name == NULL) {
 		errno = EINVAL;
 		return -1;
 	}
-	n = strrchr(path, '/');
+	memset(tmp, 0, SYSFS_PATH_MAX);
+	strcpy(tmp, path);
+	n = &tmp[strlen(tmp)-1];
+	if (strncmp(n, "/", 1) == 0)
+		*n = '\0';	
+	n = strrchr(tmp, '/');
 	if (n == NULL) {
 		errno = EINVAL;
 		return -1;
@@ -130,7 +159,8 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
 {
 	unsigned char devdir[SYSFS_PATH_MAX];
 	unsigned char linkpath[SYSFS_PATH_MAX];
-	unsigned char *d = NULL;
+	unsigned char *d = NULL, *s = NULL;
+	int slashes = 0, count = 0;
 
 	if (path == NULL || target == NULL) {
 		errno = EINVAL;
@@ -139,12 +169,8 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
 
 	memset(devdir, 0, SYSFS_PATH_MAX);
 	memset(linkpath, 0, SYSFS_PATH_MAX);
+	strncpy(devdir, path, SYSFS_PATH_MAX);
 
-	if ((sysfs_get_mnt_path(devdir, SYSFS_PATH_MAX)) != 0) {
-		dprintf("Sysfs not supported on this system\n");
-		return -1;
-	}
-								        
 	if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
 		return -1;
 	}
@@ -152,12 +178,22 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
 	d = linkpath;
 
 	/* getting rid of leading "../.." */	
-	while (*d == '/' || *d == '.')
+	while (*d == '/' || *d == '.') {
+		if (*d == '/')
+			slashes++;
 		d++;
+	}
 
 	d--;
+
+	s = &devdir[strlen(devdir)-1];
+	while (s != NULL && count != (slashes+1)) {
+		s--;
+		if (*s == '/')
+			count++;
+	}
 	
-	strcat(devdir, d);
+	strncpy(s, d, (SYSFS_PATH_MAX-strlen(devdir)));
 	strncpy(target, devdir, len);
 
 	return 0;
@@ -168,7 +204,7 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
  * sysfs_del_name: free function for sysfs_open_subsystem_list
  * @name: memory area to be freed
  */ 
-void sysfs_del_name(void *name)
+static void sysfs_del_name(void *name)
 {
 	free(name);
 }
@@ -194,8 +230,10 @@ void sysfs_close_list(struct dlist *list)
 struct dlist *sysfs_open_subsystem_list(unsigned char *name)
 {
 	unsigned char sysfs_path[SYSFS_PATH_MAX], *subsys_name = NULL;
+	unsigned char *c = NULL;
 	struct sysfs_directory *dir = NULL, *cur = NULL;
 	struct dlist *list = NULL;
+	struct stat astats;
 	
 	if (name == NULL)
 		return NULL;
@@ -205,6 +243,8 @@ struct dlist *sysfs_open_subsystem_list(unsigned char *name)
 		return NULL;
 	}
 
+	if (sysfs_trailing_slash(sysfs_path) == 0)
+		strcat(sysfs_path, "/");
 	strcat(sysfs_path, name);
 	dir = sysfs_open_directory(sysfs_path);
 	if (dir == NULL) {
@@ -235,6 +275,27 @@ struct dlist *sysfs_open_subsystem_list(unsigned char *name)
 		}
 	}
 	sysfs_close_directory(dir);
+	/*
+	 * We are now considering "block" as a "class". Hence, if the subsys
+	 * name requested here is "class", verify if "block" is supported on
+	 * this system and return the same.
+	 */ 
+	if (strcmp(name, SYSFS_CLASS_DIR) == 0) {
+		c = strstr(sysfs_path, SYSFS_CLASS_NAME);
+		if (c == NULL)
+			goto out;
+		strcpy(c, SYSFS_BLOCK_NAME);
+		if ((lstat(sysfs_path, &astats)) != 0) {
+			dprintf("stat() failed\n");
+			goto out;
+		}
+		if (S_ISDIR(astats.st_mode)) {
+			subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
+			strcpy(subsys_name, SYSFS_BLOCK_NAME);
+			dlist_unshift(list, subsys_name);
+		}
+	}
+out:
 	return list;
 }
 
@@ -259,7 +320,9 @@ struct dlist *sysfs_open_bus_devices_list(unsigned char *name)
 		return NULL;
 	}
 
-	strcat(sysfs_path, SYSFS_BUS_DIR);
+	if (sysfs_trailing_slash(sysfs_path) == 0)
+		strcat(sysfs_path, "/");
+	strcat(sysfs_path, SYSFS_BUS_NAME);
 	strcat(sysfs_path, "/");
 	strcat(sysfs_path, name);
 	strcat(sysfs_path, SYSFS_DEVICES_DIR);