Reduce the size of mount (and bypass /proc/filesystems) by using the sysfs
system call, based on work done by Glenn McGrath in December.
-Erik
diff --git a/mount.c b/mount.c
index 76cab7d..2353a8a 100644
--- a/mount.c
+++ b/mount.c
@@ -83,6 +83,7 @@
__const void *__data);
extern int umount (__const char *__special_file);
extern int umount2 (__const char *__special_file, int __flags);
+static _syscall3(int, sysfs, int, option, unsigned int, fs_index, char *, buf);
extern const char mtab_file[]; /* Defined in utility.c */
@@ -233,72 +234,24 @@
{
int status = 0;
- char buf[255];
if (strcmp(filesystemType, "auto") == 0) {
- FILE *f = xfopen("/proc/filesystems", "r");
+ int i=0;
+ const int num_of_filesystems = sysfs(3, 0, 0);
+ char buf[255];
+ filesystemType=buf;
- while (fgets(buf, sizeof(buf), f) != NULL) {
- filesystemType = buf;
- if (*filesystemType == '\t') { // Not a nodev filesystem
-
- // Add NULL termination to each line
- while (*filesystemType && *filesystemType != '\n')
- filesystemType++;
- *filesystemType = '\0';
-
- filesystemType = buf;
- filesystemType++; // hop past tab
-
- status = do_mount(blockDevice, directory, filesystemType,
- flags | MS_MGC_VAL, string_flags,
- useMtab, fakeIt, mtab_opts);
- if (status == TRUE)
- break;
- }
- }
- fclose(f);
- } else
-#if defined BB_FEATURE_USE_DEVPS_PATCH
- if (strcmp(filesystemType, "auto") == 0) {
- int fd, i, numfilesystems;
- char device[] = "/dev/mtab";
- struct k_fstype *fslist;
-
- /* open device */
- fd = open(device, O_RDONLY);
- if (fd < 0)
- perror_msg_and_die("open failed for `%s'", device);
-
- /* How many filesystems? We need to know to allocate enough space */
- numfilesystems = ioctl (fd, DEVMTAB_COUNT_FILESYSTEMS);
- if (numfilesystems<0)
- perror_msg_and_die("\nDEVMTAB_COUNT_FILESYSTEMS");
- fslist = (struct k_fstype *) xcalloc ( numfilesystems, sizeof(struct k_fstype));
-
- /* Grab the list of available filesystems */
- status = ioctl (fd, DEVMTAB_GET_FILESYSTEMS, fslist);
- if (status<0)
- perror_msg_and_die("\nDEVMTAB_GET_FILESYSTEMS");
-
- /* Walk the list trying to mount filesystems
- * that do not claim to be nodev filesystems */
- for( i = 0 ; i < numfilesystems ; i++) {
- if (fslist[i].mnt_nodev)
- continue;
- status = do_mount(blockDevice, directory, fslist[i].mnt_type,
- flags | MS_MGC_VAL, string_flags,
- useMtab, fakeIt, mtab_opts);
+ while(i < num_of_filesystems) {
+ sysfs(2, i++, filesystemType);
+ status = do_mount(blockDevice, directory, filesystemType,
+ flags | MS_MGC_VAL, string_flags,
+ useMtab, fakeIt, mtab_opts);
if (status == TRUE)
break;
}
- free( fslist);
- close(fd);
- } else
-#endif
- {
+ } else {
status = do_mount(blockDevice, directory, filesystemType,
- flags | MS_MGC_VAL, string_flags, useMtab,
- fakeIt, mtab_opts);
+ flags | MS_MGC_VAL, string_flags, useMtab,
+ fakeIt, mtab_opts);
}
if (status == FALSE) {
diff --git a/util-linux/mount.c b/util-linux/mount.c
index 76cab7d..2353a8a 100644
--- a/util-linux/mount.c
+++ b/util-linux/mount.c
@@ -83,6 +83,7 @@
__const void *__data);
extern int umount (__const char *__special_file);
extern int umount2 (__const char *__special_file, int __flags);
+static _syscall3(int, sysfs, int, option, unsigned int, fs_index, char *, buf);
extern const char mtab_file[]; /* Defined in utility.c */
@@ -233,72 +234,24 @@
{
int status = 0;
- char buf[255];
if (strcmp(filesystemType, "auto") == 0) {
- FILE *f = xfopen("/proc/filesystems", "r");
+ int i=0;
+ const int num_of_filesystems = sysfs(3, 0, 0);
+ char buf[255];
+ filesystemType=buf;
- while (fgets(buf, sizeof(buf), f) != NULL) {
- filesystemType = buf;
- if (*filesystemType == '\t') { // Not a nodev filesystem
-
- // Add NULL termination to each line
- while (*filesystemType && *filesystemType != '\n')
- filesystemType++;
- *filesystemType = '\0';
-
- filesystemType = buf;
- filesystemType++; // hop past tab
-
- status = do_mount(blockDevice, directory, filesystemType,
- flags | MS_MGC_VAL, string_flags,
- useMtab, fakeIt, mtab_opts);
- if (status == TRUE)
- break;
- }
- }
- fclose(f);
- } else
-#if defined BB_FEATURE_USE_DEVPS_PATCH
- if (strcmp(filesystemType, "auto") == 0) {
- int fd, i, numfilesystems;
- char device[] = "/dev/mtab";
- struct k_fstype *fslist;
-
- /* open device */
- fd = open(device, O_RDONLY);
- if (fd < 0)
- perror_msg_and_die("open failed for `%s'", device);
-
- /* How many filesystems? We need to know to allocate enough space */
- numfilesystems = ioctl (fd, DEVMTAB_COUNT_FILESYSTEMS);
- if (numfilesystems<0)
- perror_msg_and_die("\nDEVMTAB_COUNT_FILESYSTEMS");
- fslist = (struct k_fstype *) xcalloc ( numfilesystems, sizeof(struct k_fstype));
-
- /* Grab the list of available filesystems */
- status = ioctl (fd, DEVMTAB_GET_FILESYSTEMS, fslist);
- if (status<0)
- perror_msg_and_die("\nDEVMTAB_GET_FILESYSTEMS");
-
- /* Walk the list trying to mount filesystems
- * that do not claim to be nodev filesystems */
- for( i = 0 ; i < numfilesystems ; i++) {
- if (fslist[i].mnt_nodev)
- continue;
- status = do_mount(blockDevice, directory, fslist[i].mnt_type,
- flags | MS_MGC_VAL, string_flags,
- useMtab, fakeIt, mtab_opts);
+ while(i < num_of_filesystems) {
+ sysfs(2, i++, filesystemType);
+ status = do_mount(blockDevice, directory, filesystemType,
+ flags | MS_MGC_VAL, string_flags,
+ useMtab, fakeIt, mtab_opts);
if (status == TRUE)
break;
}
- free( fslist);
- close(fd);
- } else
-#endif
- {
+ } else {
status = do_mount(blockDevice, directory, filesystemType,
- flags | MS_MGC_VAL, string_flags, useMtab,
- fakeIt, mtab_opts);
+ flags | MS_MGC_VAL, string_flags, useMtab,
+ fakeIt, mtab_opts);
}
if (status == FALSE) {
diff --git a/utility.c b/utility.c
index df4573c..76299be 100644
--- a/utility.c
+++ b/utility.c
@@ -63,8 +63,8 @@
#include <sys/syscall.h>
#include <linux/unistd.h>
-/* Busybox mount uses either /proc/filesystems or /dev/mtab to get the
- * list of available filesystems used for the -t auto option */
+/* Busybox mount uses either /proc/mounts or /dev/mtab to
+ * get the list of currently mounted filesystems */
#if defined BB_MOUNT || defined BB_UMOUNT || defined BB_DF
# if defined BB_MTAB
const char mtab_file[] = "/etc/mtab";