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authorRob Landley2006-05-08 02:53:23 +0000
committerRob Landley2006-05-08 02:53:23 +0000
commit15fe2e11d7886d04450cabc8b40f0d396b6b6d85 (patch)
tree5bd4757d5fd5076e8caeee1866f66e942c8f454d /util-linux/mdev.c
parent17507fa4c506269f169ff8e99948086ced58f89f (diff)
downloadbusybox-15fe2e11d7886d04450cabc8b40f0d396b6b6d85.zip
busybox-15fe2e11d7886d04450cabc8b40f0d396b6b6d85.tar.gz
Shrink the code about 50 bytes, allocate less run-time memory, and add a
comment that null terminating the string we sscanf() shouldn't be required since the kernel adds \n to the end of it and sscanf will stop there.
Diffstat (limited to 'util-linux/mdev.c')
-rw-r--r--util-linux/mdev.c39
1 files changed, 19 insertions, 20 deletions
diff --git a/util-linux/mdev.c b/util-linux/mdev.c
index 5fea1b8..73938f8 100644
--- a/util-linux/mdev.c
+++ b/util-linux/mdev.c
@@ -38,23 +38,25 @@ static void make_device(char *path)
int mode = 0660;
uid_t uid = 0;
gid_t gid = 0;
+ char *temp = path + strlen(path);
- RESERVE_CONFIG_BUFFER(temp, PATH_MAX);
+ /* Try to read major/minor string. Note that the kernel puts \n after
+ * the data, so we don't need to worry about null terminating the string
+ * because sscanf() will stop at the first nondigit, which \n is. We
+ * also depend on path having writeable space after it. */
- /* Try to read major/minor string */
-
- snprintf(temp, PATH_MAX, "%s/dev", path);
- fd = open(temp, O_RDONLY);
- len = read(fd, temp, PATH_MAX-1);
+ strcat(path, "/dev");
+ fd = open(path, O_RDONLY);
+ len = read(fd, temp + 1, 64);
+ *temp++ = 0;
close(fd);
- if (len < 1) goto end;
+ if (len < 1) return;
/* Determine device name, type, major and minor */
device_name = strrchr(path, '/') + 1;
- type = strncmp(path+5, "block/", 6) ? S_IFCHR : S_IFBLK;
- if (sscanf(temp, "%d:%d", &major, &minor) != 2)
- goto end;
+ type = path[5]=='c' ? S_IFCHR : S_IFBLK;
+ if (sscanf(temp, "%d:%d", &major, &minor) != 2) return;
/* If we have a config file, look up permissions for this device */
@@ -167,18 +169,14 @@ found_device:
}
}
- sprintf(temp, "%s/%s", DEV_PATH, device_name);
umask(0);
- if (mknod(temp, mode | type, makedev(major, minor)) && errno != EEXIST)
- bb_perror_msg_and_die("mknod %s failed", temp);
+ if (mknod(device_name, mode | type, makedev(major, minor)) && errno != EEXIST)
+ bb_perror_msg_and_die("mknod %s failed", device_name);
if (major==root_major && minor==root_minor)
- symlink(temp,DEV_PATH "/root");
+ symlink(device_name, "root");
- if (ENABLE_FEATURE_MDEV_CONF) chown(temp,uid,gid);
-
-end:
- RELEASE_CONFIG_BUFFER(temp);
+ if (ENABLE_FEATURE_MDEV_CONF) chown(device_name, uid, gid);
}
/* Recursive search of /sys/block or /sys/class. path must be a writeable
@@ -220,6 +218,8 @@ int mdev_main(int argc, char *argv[])
char *env_path;
RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
+ bb_xchdir(DEV_PATH);
+
/* Scan */
if (argc == 2 && !strcmp(argv[1],"-s")) {
@@ -245,8 +245,7 @@ int mdev_main(int argc, char *argv[])
sprintf(temp, "/sys%s", env_path);
make_device(temp);
} else if (!strcmp(action, "remove")) {
- sprintf(temp, "%s/%s", DEV_PATH, strrchr(env_path, '/') + 1);
- unlink(temp);
+ unlink(strrchr(env_path, '/') + 1);
}
}