1 files changed, 208 insertions, 0 deletions

diff --git a/e2fsprogs/ext2fs/finddev.c b/e2fsprogs/ext2fs/finddev.c
new file mode 100644
index 000000000..fa2cadde4
--- /dev/null
+++ b/e2fsprogs/ext2fs/finddev.c
@@ -0,0 +1,208 @@
+/*
+ * finddev.c -- this routine attempts to find a particular device in
+ *      /dev
+ * 
+ * Copyright (C) 2000 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#include <dirent.h>
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#if HAVE_SYS_MKDEV_H
+#include <sys/mkdev.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+
+struct dir_list {
+        char    *name;
+        struct dir_list *next;
+};
+
+/*
+ * This function adds an entry to the directory list
+ */
+static void add_to_dirlist(const char *name, struct dir_list **list)
+{
+        struct dir_list *dp;
+
+        dp = malloc(sizeof(struct dir_list));
+        if (!dp)
+                return;
+        dp->name = malloc(strlen(name)+1);
+        if (!dp->name) {
+                free(dp);
+                return;
+        }
+        strcpy(dp->name, name);
+        dp->next = *list;
+        *list = dp;
+}
+
+/*
+ * This function frees a directory list
+ */
+static void free_dirlist(struct dir_list **list)
+{
+        struct dir_list *dp, *next;
+
+        for (dp = *list; dp; dp = next) {
+                next = dp->next;
+                free(dp->name);
+                free(dp);
+        }
+        *list = 0;
+}
+
+static int scan_dir(char *dir_name, dev_t device, struct dir_list **list,
+                    char **ret_path)
+{
+        DIR     *dir;
+        struct dirent *dp;
+        char    path[1024], *cp;
+        int     dirlen;
+        struct stat st;
+
+        dirlen = strlen(dir_name);
+        if ((dir = opendir(dir_name)) == NULL)
+                return errno;
+        dp = readdir(dir);
+        while (dp) {
+                if (dirlen + strlen(dp->d_name) + 2 >= sizeof(path))
+                        goto skip_to_next;
+                if (dp->d_name[0] == '.' &&
+                    ((dp->d_name[1] == 0) ||
+                     ((dp->d_name[1] == '.') && (dp->d_name[2] == 0))))
+                        goto skip_to_next;
+                sprintf(path, "%s/%s", dir_name, dp->d_name);
+                if (stat(path, &st) < 0)
+                        goto skip_to_next;
+                if (S_ISDIR(st.st_mode))
+                        add_to_dirlist(path, list);
+                if (S_ISBLK(st.st_mode) && st.st_rdev == device) {
+                        cp = malloc(strlen(path)+1);
+                        if (!cp) {
+                                closedir(dir);
+                                return ENOMEM;
+                        }
+                        strcpy(cp, path);
+                        *ret_path = cp;
+                        goto success;
+                }
+        skip_to_next:
+                dp = readdir(dir);
+        }
+success:
+        closedir(dir);
+        return 0;
+}
+
+/*
+ * This function finds the pathname to a block device with a given
+ * device number.  It returns a pointer to allocated memory to the
+ * pathname on success, and NULL on failure.
+ */
+char *ext2fs_find_block_device(dev_t device)
+{
+        struct dir_list *list = 0, *new_list = 0;
+        struct dir_list *current;
+        char    *ret_path = 0;
+
+        /*
+         * Add the starting directories to search...
+         */
+        add_to_dirlist("/devices", &list);
+        add_to_dirlist("/devfs", &list);
+        add_to_dirlist("/dev", &list);
+        
+        while (list) {
+                current = list;
+                list = list->next;
+#ifdef DEBUG
+                printf("Scanning directory %s\n", current->name);
+#endif
+                scan_dir(current->name, device, &new_list, &ret_path);
+                free(current->name);
+                free(current);
+                if (ret_path)
+                        break;
+                /*
+                 * If we're done checking at this level, descend to
+                 * the next level of subdirectories. (breadth-first)
+                 */
+                if (list == 0) {
+                        list = new_list;
+                        new_list = 0;
+                }
+        }
+        free_dirlist(&list);
+        free_dirlist(&new_list);
+        return ret_path;
+}
+
+        
+#ifdef DEBUG
+int main(int argc, char** argv)
+{
+        char    *devname, *tmp;
+        int     major, minor;
+        dev_t   device;
+        const char *errmsg = "Couldn't parse %s: %s\n";
+
+        if ((argc != 2) && (argc != 3)) {
+                fprintf(stderr, "Usage: %s device_number\n", argv[0]);
+                fprintf(stderr, "\t: %s major minor\n", argv[0]);
+                exit(1);
+        }
+        if (argc == 2) {
+                device = strtoul(argv[1], &tmp, 0);
+                if (*tmp) {
+                        fprintf(stderr, errmsg, "device number", argv[1]);
+                        exit(1);
+                }
+        } else {
+                major = strtoul(argv[1], &tmp, 0);
+                if (*tmp) {
+                        fprintf(stderr, errmsg, "major number", argv[1]);
+                        exit(1);
+                }
+                minor = strtoul(argv[2], &tmp, 0);
+                if (*tmp) {
+                        fprintf(stderr, errmsg, "minor number", argv[2]);
+                        exit(1);
+                }
+                device = makedev(major, minor);
+                printf("Looking for device 0x%04x (%d:%d)\n", device,
+                       major, minor);
+        }
+        devname = ext2fs_find_block_device(device);
+        if (devname) {
+                printf("Found device!  %s\n", devname);
+                free(devname);
+        } else {
+                printf("Couldn't find device.\n");
+        }
+        return 0;
+}
+        
+#endif