add mknod wrapper
authorJohn Crispin <blogic@openwrt.org>
Fri, 8 Mar 2013 22:48:20 +0000 (23:48 +0100)
committerJohn Crispin <blogic@openwrt.org>
Wed, 13 Mar 2013 17:58:13 +0000 (18:58 +0100)
mkdev.c [new file with mode: 0644]

diff --git a/mkdev.c b/mkdev.c
new file mode 100644 (file)
index 0000000..c502f70
--- /dev/null
+++ b/mkdev.c
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#define _BSD_SOURCE
+
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <dirent.h>
+#include <limits.h>
+#include <fnmatch.h>
+
+#include "procd.h"
+
+static char **patterns;
+static int n_patterns;
+static char buf[PATH_MAX];
+static char buf2[PATH_MAX];
+static unsigned int mode = 0600;
+
+static bool find_pattern(const char *name)
+{
+       int i;
+
+       for (i = 0; i < n_patterns; i++)
+               if (!fnmatch(patterns[i], name, 0))
+                       return true;
+
+       return false;
+}
+
+static void make_dev(const char *path, bool block, int major, int minor)
+{
+       unsigned int _mode = mode | (block ? S_IFBLK : S_IFCHR);
+       DEBUG(2, "Creating %s device %s(%d,%d)\n",
+               block ? "block" : "character",
+               path, major, minor);
+
+       mknod(path, _mode, makedev(major, minor));
+}
+
+static void find_devs(bool block)
+{
+       char *path = block ? "/sys/dev/block" : "/sys/dev/char";
+       struct dirent *dp;
+       DIR *dir;
+
+       dir = opendir(path);
+       if (!dir)
+               return;
+
+       path = buf2 + sprintf(buf2, "%s/", path);
+       while ((dp = readdir(dir)) != NULL) {
+               char *c;
+               int major = 0, minor = 0;
+               int len;
+
+               if (dp->d_type != DT_LNK)
+                       continue;
+
+               if (sscanf(dp->d_name, "%d:%d", &major, &minor) != 2)
+                       continue;
+
+               strcpy(path, dp->d_name);
+               len = readlink(buf2, buf, sizeof(buf));
+               if (len <= 0)
+                       continue;
+
+               buf[len] = 0;
+               if (!find_pattern(buf))
+                       continue;
+
+               c = strrchr(buf, '/');
+               if (!c)
+                       continue;
+
+               c++;
+               make_dev(c, block, major, minor);
+       }
+       closedir(dir);
+}
+
+static char *add_pattern(const char *name)
+{
+       char *str = malloc(strlen(name) + 2);
+
+       str[0] = '*';
+       strcpy(str + 1, name);
+       return str;
+}
+
+int mkdev(const char *name, int _mode)
+{
+       char *pattern;
+
+       if (chdir("/dev")) {
+               perror("chdir");
+               return 1;
+       }
+
+       pattern = add_pattern(name);
+       patterns = &pattern;
+       mode = _mode;
+       n_patterns = 1;
+       find_devs(true);
+       find_devs(false);
+       chdir("/");
+
+       return 0;
+}