[PATCH] udevstart: simplify "dev" file searching

Just stat() the "dev" file in the device directory instead of
opening the directory and iterating over all entries.

Make udevstart work with the settings in with udev.conf so we can
run a test program.

Add a test for udevstart.

Remove changelog stuff from code. We should never start with this
silly thing.

1 files changed, 67 insertions, 76 deletions

diff --git a/udev_start.c b/udev_start.c
index 8c7a06b5af..dcb4293345 100644
--- a/udev_start.c
+++ b/udev_start.c
@@ -30,6 +30,7 @@
 #include <ctype.h>
 #include <dirent.h>
 #include <sys/wait.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
 
@@ -40,22 +41,22 @@
 #include "udev.h"
 
 
-#define MAX_PATHLEN		1024
-#define SYSBLOCK		"/sys/block"
-#define SYSCLASS		"/sys/class"
+#define MAX_PATH_SIZE		512
 
 struct device {
 	struct list_head list;
-	char path[MAX_PATHLEN];
-	char subsys[MAX_PATHLEN];
+	char path[MAX_PATH_SIZE];
+	char subsys[MAX_PATH_SIZE];
 };
 
 /* sort files in lexical order */
-static int device_list_insert(char *path, char *subsystem, struct list_head *device_list)
+static int device_list_insert(const char *path, char *subsystem, struct list_head *device_list)
 {
 	struct device *loop_device;
 	struct device *new_device;
 
+	dbg("insert: '%s'\n", path);
+
 	list_for_each_entry(loop_device, device_list, list) {
 		if (strcmp(loop_device->path, path) > 0) {
 			break;
@@ -87,18 +88,20 @@ static char *first_list[] = {
 	NULL,
 };
 
-static int add_device(char *devpath, char *subsystem)
+static int add_device(const char *path, const char *subsystem)
 {
 	struct udevice udev;
-	char path[SYSFS_PATH_MAX];
 	struct sysfs_class_device *class_dev;
+	const char *devpath;
+
+	devpath = &path[strlen(sysfs_path)];
 
 	/* set environment for callouts and dev.d/ */
 	setenv("DEVPATH", devpath, 1);
 	setenv("SUBSYSTEM", subsystem, 1);
 
-	snprintf(path, SYSFS_PATH_MAX, "%s%s", sysfs_path, devpath);
-	path[SYSFS_PATH_MAX-1] = '\0';
+	dbg("exec  : '%s' (%s)\n", devpath, path);
+
 	class_dev = sysfs_open_class_device_path(path);
 	if (class_dev == NULL) {
 		dbg ("sysfs_open_class_device_path failed");
@@ -127,7 +130,7 @@ static void exec_list(struct list_head *device_list)
 
 	/* handle the "first" type devices first */
 	list_for_each_entry_safe(loop_device, tmp_device, device_list, list) {
-		for (i=0; first_list[i] != NULL; i++) {
+		for (i = 0; first_list[i] != NULL; i++) {
 			if (strncmp(loop_device->path, first_list[i], strlen(first_list[i])) == 0) {
 				add_device(loop_device->path, loop_device->subsys);
 				list_del(&loop_device->list);
@@ -140,7 +143,7 @@ static void exec_list(struct list_head *device_list)
 	/* handle the devices we are allowed to, excluding the "last" type devices */
 	list_for_each_entry_safe(loop_device, tmp_device, device_list, list) {
 		int found = 0;
-		for (i=0; last_list[i] != NULL; i++) {
+		for (i = 0; last_list[i] != NULL; i++) {
 			if (strncmp(loop_device->path, last_list[i], strlen(last_list[i])) == 0) {
 				found = 1;
 				break;
@@ -162,56 +165,61 @@ static void exec_list(struct list_head *device_list)
 	}
 }
 
+static int has_devt(const char *directory)
+{
+	char filename[MAX_PATH_SIZE];
+	struct stat statbuf;
+
+	snprintf(filename, MAX_PATH_SIZE, "%s/dev", directory);
+	filename[MAX_PATH_SIZE-1] = '\0';
+
+	if (stat(filename, &statbuf) == 0)
+		return 1;
+
+	return 0;
+}
+
 static void udev_scan_block(void)
 {
+	char base[MAX_PATH_SIZE];
 	DIR *dir;
 	struct dirent *dent;
 	LIST_HEAD(device_list);
 
-	dir = opendir(SYSBLOCK);
+	snprintf(base, MAX_PATH_SIZE, "%s/block", sysfs_path);
+	base[MAX_PATH_SIZE-1] = '\0';
+
+	dir = opendir(base);
 	if (dir != NULL) {
 		for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
-			char dirname[MAX_PATHLEN];
+			char dirname[MAX_PATH_SIZE];
 			DIR *dir2;
 			struct dirent *dent2;
 
-			if ((strcmp(dent->d_name, ".") == 0) ||
-			    (strcmp(dent->d_name, "..") == 0))
+			if (dent->d_name[0] == '.')
 				continue;
 
-			snprintf(dirname, MAX_PATHLEN, "/block/%s", dent->d_name);
-			dirname[MAX_PATHLEN-1] = '\0';
-			device_list_insert(dirname, "block", &device_list);
+			snprintf(dirname, MAX_PATH_SIZE, "%s/%s", base, dent->d_name);
+			dirname[MAX_PATH_SIZE-1] = '\0';
+			if (has_devt(dirname))
+				device_list_insert(dirname, "block", &device_list);
+			else
+				continue;
 
-			snprintf(dirname, MAX_PATHLEN, "%s/%s", SYSBLOCK, dent->d_name);
+			snprintf(dirname, MAX_PATH_SIZE, "%s/%s", base, dent->d_name);
 			dir2 = opendir(dirname);
 			if (dir2 != NULL) {
 				for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
-					char dirname2[MAX_PATHLEN];
-					DIR *dir3;
-					struct dirent *dent3;
+					char dirname2[MAX_PATH_SIZE];
 
-					if ((strcmp(dent2->d_name, ".") == 0) ||
-					    (strcmp(dent2->d_name, "..") == 0))
+					if (dent2->d_name[0] == '.')
 						continue;
 
-					snprintf(dirname2, MAX_PATHLEN, "%s/%s", dirname, dent2->d_name);
-					dirname2[MAX_PATHLEN-1] = '\0';
-
-					dir3 = opendir(dirname2);
-					if (dir3 != NULL) {
-						for (dent3 = readdir(dir3); dent3 != NULL; dent3 = readdir(dir3)) {
-							char filename[MAX_PATHLEN];
-
-							if (strcmp(dent3->d_name, "dev") == 0) {
-								snprintf(filename, MAX_PATHLEN, "/block/%s/%s",
-									 dent->d_name, dent2->d_name);
-								filename[MAX_PATHLEN-1] = '\0';
-								device_list_insert(filename, "block", &device_list);
-							}
-						}
-						closedir(dir3);
-					}
+					snprintf(dirname2, MAX_PATH_SIZE, "%s/%s", dirname, dent2->d_name);
+					dirname2[MAX_PATH_SIZE-1] = '\0';
+
+					if (has_devt(dirname2))
+						device_list_insert(dirname2, "block", &device_list);
 				}
 				closedir(dir2);
 			}
@@ -224,59 +232,42 @@ static void udev_scan_block(void)
 
 static void udev_scan_class(void)
 {
+	char base[MAX_PATH_SIZE];
 	DIR *dir;
 	struct dirent *dent;
 	LIST_HEAD(device_list);
 
-	dir = opendir(SYSCLASS);
+	snprintf(base, MAX_PATH_SIZE, "%s/class", sysfs_path);
+	base[MAX_PATH_SIZE-1] = '\0';
+
+	dir = opendir(base);
 	if (dir != NULL) {
 		for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
-			char dirname[MAX_PATHLEN];
+			char dirname[MAX_PATH_SIZE];
 			DIR *dir2;
 			struct dirent *dent2;
 
-			if ((strcmp(dent->d_name, ".") == 0) ||
-			    (strcmp(dent->d_name, "..") == 0))
+			if (dent->d_name[0] == '.')
 				continue;
 
-			snprintf(dirname, MAX_PATHLEN, "%s/%s", SYSCLASS, dent->d_name);
-			dirname[MAX_PATHLEN-1] = '\0';
+			snprintf(dirname, MAX_PATH_SIZE, "%s/%s", base, dent->d_name);
+			dirname[MAX_PATH_SIZE-1] = '\0';
 			dir2 = opendir(dirname);
 			if (dir2 != NULL) {
 				for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
-					char dirname2[MAX_PATHLEN];
-					DIR *dir3;
-					struct dirent *dent3;
+					char dirname2[MAX_PATH_SIZE];
 
-					if ((strcmp(dent2->d_name, ".") == 0) ||
-					    (strcmp(dent2->d_name, "..") == 0))
+					if (dent2->d_name[0] == '.')
 						continue;
 
+					snprintf(dirname2, MAX_PATH_SIZE, "%s/%s", dirname, dent2->d_name);
+					dirname2[MAX_PATH_SIZE-1] = '\0';
+
 					/* pass the net class as it is */
-					if (strcmp(dent->d_name, "net") == 0) {
-						snprintf(dirname2, MAX_PATHLEN, "/class/net/%s", dent2->d_name);
+					if (strcmp(dent->d_name, "net") == 0)
 						device_list_insert(dirname2, "net", &device_list);
-						continue;
-					}
-
-					snprintf(dirname2, MAX_PATHLEN, "%s/%s", dirname, dent2->d_name);
-					dirname2[MAX_PATHLEN-1] = '\0';
-					dir3 = opendir(dirname2);
-					if (dir3 != NULL) {
-						for (dent3 = readdir(dir3); dent3 != NULL; dent3 = readdir(dir3)) {
-							char filename[MAX_PATHLEN];
-
-							/* pass devices with a "dev" file */
-							if (strcmp(dent3->d_name, "dev") == 0) {
-								snprintf(filename, MAX_PATHLEN, "/class/%s/%s",
-									 dent->d_name, dent2->d_name);
-								filename[MAX_PATHLEN-1] = '\0';
-								device_list_insert(filename, dent->d_name, &device_list);
-								break;
-							}
-						}
-						closedir(dir3);
-					}
+					else if (has_devt(dirname2))
+						device_list_insert(dirname2, dent->d_name, &device_list);
 				}
 				closedir(dir2);
 			}