:: commit 3f37d82cdd3ec231e822588ff6376bd563070476
got directory reading and more specifically root directory reading
diff --git a/stage23/fs/ntfs.h b/stage23/fs/ntfs.h
index dbb22d34..6b80092e 100644
--- a/stage23/fs/ntfs.h
+++ b/stage23/fs/ntfs.h
@@ -33,16 +33,22 @@ struct ntfs_file_handle {
struct volume *part;
struct ntfs_bpb bpb;
- uint8_t mft_run_list[256];
- uint8_t root_run_list[128];
- uint8_t resident_index[256];
- uint8_t attribute_list[256];
-
- uint64_t mft_offset;
+ // file record sizes
uint64_t file_record_size;
uint64_t sectors_per_file_record;
+ // MFT info, the offset and its runlist
+ uint64_t mft_offset;
+ uint8_t mft_run_list[256];
+
+ // the runlist, resident index and attribute list of the
+ // current open file/directory
+ uint8_t run_list[128];
+ uint8_t resident_index[256];
+ uint8_t attribute_list[256];
+
+ // info about the current file
uint32_t size_bytes;
};
diff --git a/stage23/fs/ntfs.s2.c b/stage23/fs/ntfs.s2.c
index 39df29a8..a58faa9e 100644
--- a/stage23/fs/ntfs.s2.c
+++ b/stage23/fs/ntfs.s2.c
@@ -1,5 +1,5 @@
#include <fs/ntfs.h>
-
+#include <mm/pmm.h>
#include <lib/print.h>
#include <stdbool.h>
@@ -102,6 +102,45 @@ int ntfs_check_signature(struct volume *part) {
return 1;
}
+// the temp buffer is used for storing dirs and alike
+// in memory, because limine only has allocate without
+// free we are going to allocate it once globally and just
+// make sure to only use it in the ntfs_open function...
+static uint8_t *temp_buffer = NULL;
+static size_t temp_buffer_size = 0;
+
+/**
+ * Get an attribute from the given file record
+ */
+static bool ntfs_get_file_record_attr(uint8_t* file_record, uint32_t attr_type, uint8_t **out_attr) {
+ struct mft_file_record *fr = (struct mft_file_record *)file_record;
+
+ // get the offset to the first attribute
+ uint8_t *cur_attr_ptr = file_record + fr->attribute_offset;
+
+ while (true) {
+ // TODO: don't check for the min size, but for the actual size...
+ if (cur_attr_ptr + sizeof(struct file_record_attr_header) > file_record + MIN_FILE_RECORD_SIZE)
+ panic("NTFS: File record attribute is outside of file record");
+
+ struct file_record_attr_header *cur_attr = (struct file_record_attr_header *)cur_attr_ptr;
+
+ if (cur_attr->type == attr_type) {
+ *out_attr = cur_attr_ptr;
+ return true;
+ }
+
+ // we either found an attr with higher type or the end type
+ if (cur_attr->type > attr_type || cur_attr->type == 0xFF)
+ return false;
+
+ if (cur_attr->length == 0)
+ panic("NTFS: File record attribute has zero length");
+
+ cur_attr_ptr += cur_attr->length;
+ }
+}
+
/**
* Gets a count and cluster from the runlist, if next is true then it updates the list intenrally
* so the next call will return the next element
@@ -201,7 +240,7 @@ static bool ntfs_get_file_record(struct ntfs_file_handle *handle, uint64_t mft_r
panic("NTFS: Failed to read file record from mft");
// make sure this is a valid file record
- struct mft_file_record* fr = (struct mft_file_record*)file_record_buffer;
+ struct mft_file_record *fr = (struct mft_file_record *)file_record_buffer;
if (strncmp(fr->name, "FILE", SIZEOF_ARRAY(fr->name)))
panic("NTFS: File record has invalid signature (got %c%c%c%c, should be FILE)!",
fr->name[0], fr->name[1], fr->name[2], fr->name[3]);
@@ -213,44 +252,57 @@ static bool ntfs_get_file_record(struct ntfs_file_handle *handle, uint64_t mft_r
/**
* Read the the directory's file record from the mft
*/
-static bool ntfs_read_directory(struct ntfs_file_handle *handle, uint64_t mft_record, uint8_t *file_record) {
+static int ntfs_read_directory(struct ntfs_file_handle *handle, uint64_t mft_record, uint8_t *file_record) {
// get the record of the directory
if (!ntfs_get_file_record(handle, mft_record, file_record))
- return false;
-
- return true;
-}
-
-/**
- * Get an attribute from the given file record
- */
-static bool ntfs_get_file_record_attr(uint8_t* file_record, uint32_t attr_type, uint8_t **out_attr) {
- struct mft_file_record *fr = (struct mft_file_record *)file_record;
-
- // get the offset to the first attribute
- uint8_t* cur_attr_ptr = file_record + fr->attribute_offset;
-
- while (true) {
- // TODO: don't check for the min size, but for the actual size...
- if (cur_attr_ptr + sizeof(struct file_record_attr_header) > file_record + MIN_FILE_RECORD_SIZE)
- panic("NTFS: File record attribute is outside of file record");
+ return 0;
- struct file_record_attr_header *cur_attr = (struct file_record_attr_header *)cur_attr_ptr;
+ //
+ // get the runlist of the directory
+ //
- if (cur_attr->type == attr_type) {
- *out_attr = cur_attr_ptr;
- return true;
+ // get the index alloc attribute, it should have the runlist offset
+ // copy the runlist from it to our handle for easier access
+ uint8_t *index_alloc_ptr;
+ if (!ntfs_get_file_record_attr(file_record, FR_ATTRIBUTE_INDEX_ALLOC, &index_alloc_ptr))
+ panic("NTFS: Directory has no runlist?!");
+ struct file_record_attr_header_non_res *index_alloc = (struct file_record_attr_header_non_res *)index_alloc_ptr;
+ uint8_t *runlist_ptr = index_alloc_ptr + index_alloc->run_offset;
+ if (runlist_ptr - file_record + 128u > handle->file_record_size)
+ panic("NTFS: runlist is outside of file record!");
+ memcpy(handle->run_list, runlist_ptr, sizeof(handle->run_list));
+
+ // calculate the directory size by just going through the runlist
+ uint8_t *runlist = handle->run_list;
+ uint64_t dir_size = 0;
+ uint64_t cluster = 0;
+ uint64_t cluster_count = 0;
+ bool status = false;
+ do {
+ status = ntfs_get_next_run_list_element(&runlist, &cluster_count, &cluster, true);
+ if (status)
+ dir_size += cluster_count;
+ } while(status);
+ dir_size *= handle->bpb.sectors_per_cluster * handle->bpb.bytes_per_sector;
+
+ // allocate a buffer for the directory data
+ if (temp_buffer == NULL) {
+ // allocate enough just in case, idk how much is good
+ temp_buffer_size = dir_size > 64 * 1024 ? dir_size : 64 * 1024;
+ temp_buffer = ext_mem_alloc(temp_buffer_size);
+ } else {
+ // we must truncate it...
+ if (dir_size > temp_buffer_size) {
+ dir_size = temp_buffer_size;
}
+ }
- // we either found an attr with higher type or the end type
- if (cur_attr->type > attr_type || cur_attr->type == 0xFF)
- return false;
-
- if (cur_attr->length == 0)
- panic("NTFS: File record attribute has zero length");
+ // read the directory
+ if (ntfs_read(handle, temp_buffer, 0, dir_size) != (int)dir_size)
+ panic("NTFS: EOF before reading directory fully...");
- cur_attr_ptr += cur_attr->length;
- }
+ // return the size of the directory
+ return dir_size;
}
/**
@@ -261,14 +313,15 @@ static void ntfs_read_root(struct ntfs_file_handle *handle) {
handle->mft_offset = (uint64_t)handle->bpb.mft_cluster * (uint64_t)handle->bpb.sectors_per_cluster * (uint64_t)handle->bpb.bytes_per_sector;
// read the mft file record, this should be the size of a sector
- uint8_t file_record_buffer[handle->file_record_size];
+ uint8_t file_record_buffer[MIN_FILE_RECORD_SIZE];
if (!volume_read(handle->part, file_record_buffer, handle->mft_offset, sizeof(file_record_buffer)))
panic("NTFS: Failed to read MFT file record");
// get the file attribute
- struct file_record_attr_header_non_res *attr;
- if (!ntfs_get_file_record_attr(file_record_buffer, FR_ATTRIBUTE_DATA, (uint8_t **)&attr))
+ uint8_t *attr_ptr = NULL;
+ if (!ntfs_get_file_record_attr(file_record_buffer, FR_ATTRIBUTE_DATA, &attr_ptr))
panic("NTFS: MFT file record missing DATA attribute");
+ struct file_record_attr_header_non_res *attr = (struct file_record_attr_header_non_res *)attr_ptr;
// verify the attr and run list are in the buffer
if ((uint8_t *)attr + sizeof(*attr) > file_record_buffer + sizeof(file_record_buffer))
@@ -304,7 +357,7 @@ int ntfs_open(struct ntfs_file_handle *ret, struct volume *part, const char *pat
ret->sectors_per_file_record = 1;
ret->file_record_size = ret->bpb.bytes_per_sector;
}
-
+
// now prepare the root directory so we can search for
// the rest of the stuff
ntfs_read_root(ret);
@@ -316,9 +369,55 @@ int ntfs_open(struct ntfs_file_handle *ret, struct volume *part, const char *pat
}
int ntfs_read(struct ntfs_file_handle *file, void *buf, uint64_t loc, uint64_t count) {
- (void)file;
- (void)buf;
- (void)loc;
- (void)count;
- return 1;
+ // get the runlist
+ uint8_t *runlist = file->run_list;
+
+ // we are going to go over the runlist until we get to the offset
+ // once we get to the offset we are going to continue going over
+ // the runlist while copying bytes
+ uint64_t wanted_to_read = count;
+ uint64_t bytes_per_cluster = file->bpb.sectors_per_cluster * file->bpb.bytes_per_sector;
+ do {
+ // get the next element from the runlist
+ uint64_t cluster_count;
+ uint64_t cluster;
+ if (!ntfs_get_next_run_list_element(&runlist, &cluster_count, &cluster, true))
+ break;
+
+ // calculate the cont size and offset on disk
+ uint64_t total_cont_bytes = cluster_count * bytes_per_cluster;
+ uint64_t abs_byte = cluster * bytes_per_cluster;
+
+ // check if we arrived at the wanted offset
+ if (loc != 0) {
+ if (loc >= total_cont_bytes) {
+ // we need to go more...
+ loc -= total_cont_bytes;
+ } else {
+ // we got to the offset, adjust base and size
+ // and set the loc to 0
+ total_cont_bytes -= loc;
+ abs_byte += loc;
+ loc = 0;
+ }
+ }
+
+ if (loc == 0) {
+ // get how much we wanna read now and
+ // subtract that from the total we need
+ // to read
+ size_t read_now = total_cont_bytes;
+ if (read_now > count) {
+ read_now = count;
+ }
+ count -= read_now;
+
+ // read it!
+ if (!volume_read(file->part, buf, abs_byte, read_now))
+ panic("NTFS: Runlist points to outside the volume (%x)", abs_byte);
+ }
+ } while(count);
+
+ // return how much we read...
+ return wanted_to_read - count;
}
