fs: exfat: Import libexfat from fuse-exfat
Import most of libexfat from [1] except for log.c verbatim. The code
does not even compile and further adjustments and integration into
U-Boot filesystem code is in the next patch.
[1] https://github.com/relan/exfat
0b41c6d3560d ("CI: bump FreeBSD to 13.1.")
Acked-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/fs/exfat/node.c b/fs/exfat/node.c
new file mode 100644
index 0000000..88b1357
--- /dev/null
+++ b/fs/exfat/node.c
@@ -0,0 +1,1243 @@
+/*
+ node.c (09.10.09)
+ exFAT file system implementation library.
+
+ Free exFAT implementation.
+ Copyright (C) 2010-2023 Andrew Nayenko
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 2 of the License, or
+ (at your option) any later version.
+
+ 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.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "exfat.h"
+#include <errno.h>
+#include <string.h>
+#include <inttypes.h>
+
+#define EXFAT_ENTRY_NONE (-1)
+
+struct exfat_node* exfat_get_node(struct exfat_node* node)
+{
+ /* if we switch to multi-threaded mode we will need atomic
+ increment here and atomic decrement in exfat_put_node() */
+ node->references++;
+ return node;
+}
+
+void exfat_put_node(struct exfat* ef, struct exfat_node* node)
+{
+ char buffer[EXFAT_UTF8_NAME_BUFFER_MAX];
+
+ --node->references;
+ if (node->references < 0)
+ {
+ exfat_get_name(node, buffer);
+ exfat_bug("reference counter of '%s' is below zero", buffer);
+ }
+ else if (node->references == 0 && node != ef->root)
+ {
+ if (node->is_dirty)
+ {
+ exfat_get_name(node, buffer);
+ exfat_warn("dirty node '%s' with zero references", buffer);
+ }
+ }
+}
+
+/**
+ * This function must be called on rmdir and unlink (after the last
+ * exfat_put_node()) to free clusters.
+ */
+int exfat_cleanup_node(struct exfat* ef, struct exfat_node* node)
+{
+ int rc = 0;
+
+ if (node->references != 0)
+ exfat_bug("unable to cleanup a node with %d references",
+ node->references);
+
+ if (node->is_unlinked)
+ {
+ /* free all clusters and node structure itself */
+ rc = exfat_truncate(ef, node, 0, true);
+ /* free the node even in case of error or its memory will be lost */
+ free(node);
+ }
+ return rc;
+}
+
+static int read_entries(struct exfat* ef, struct exfat_node* dir,
+ struct exfat_entry* entries, int n, off_t offset)
+{
+ ssize_t size;
+
+ if (!(dir->attrib & EXFAT_ATTRIB_DIR))
+ exfat_bug("attempted to read entries from a file");
+
+ size = exfat_generic_pread(ef, dir, entries,
+ sizeof(struct exfat_entry[n]), offset);
+ if (size == (ssize_t) sizeof(struct exfat_entry) * n)
+ return 0; /* success */
+ if (size == 0)
+ return -ENOENT;
+ if (size < 0)
+ return -EIO;
+ exfat_error("read %zd bytes instead of %zu bytes", size,
+ sizeof(struct exfat_entry[n]));
+ return -EIO;
+}
+
+static int write_entries(struct exfat* ef, struct exfat_node* dir,
+ const struct exfat_entry* entries, int n, off_t offset)
+{
+ ssize_t size;
+
+ if (!(dir->attrib & EXFAT_ATTRIB_DIR))
+ exfat_bug("attempted to write entries into a file");
+
+ size = exfat_generic_pwrite(ef, dir, entries,
+ sizeof(struct exfat_entry[n]), offset);
+ if (size == (ssize_t) sizeof(struct exfat_entry) * n)
+ return 0; /* success */
+ if (size < 0)
+ return -EIO;
+ exfat_error("wrote %zd bytes instead of %zu bytes", size,
+ sizeof(struct exfat_entry[n]));
+ return -EIO;
+}
+
+static struct exfat_node* allocate_node(void)
+{
+ struct exfat_node* node = malloc(sizeof(struct exfat_node));
+ if (node == NULL)
+ {
+ exfat_error("failed to allocate node");
+ return NULL;
+ }
+ memset(node, 0, sizeof(struct exfat_node));
+ return node;
+}
+
+static void init_node_meta1(struct exfat_node* node,
+ const struct exfat_entry_meta1* meta1)
+{
+ node->attrib = le16_to_cpu(meta1->attrib);
+ node->continuations = meta1->continuations;
+ node->mtime = exfat_exfat2unix(meta1->mdate, meta1->mtime,
+ meta1->mtime_cs, meta1->mtime_tzo);
+ /* there is no centiseconds field for atime */
+ node->atime = exfat_exfat2unix(meta1->adate, meta1->atime,
+ 0, meta1->atime_tzo);
+}
+
+static void init_node_meta2(struct exfat_node* node,
+ const struct exfat_entry_meta2* meta2)
+{
+ node->valid_size = le64_to_cpu(meta2->valid_size);
+ node->size = le64_to_cpu(meta2->size);
+ node->start_cluster = le32_to_cpu(meta2->start_cluster);
+ node->fptr_cluster = node->start_cluster;
+ node->is_contiguous = ((meta2->flags & EXFAT_FLAG_CONTIGUOUS) != 0);
+}
+
+static void init_node_name(struct exfat_node* node,
+ const struct exfat_entry* entries, int n)
+{
+ int i;
+
+ for (i = 0; i < n; i++)
+ memcpy(node->name + i * EXFAT_ENAME_MAX,
+ ((const struct exfat_entry_name*) &entries[i])->name,
+ EXFAT_ENAME_MAX * sizeof(le16_t));
+}
+
+static bool check_entries(const struct exfat_entry* entry, int n)
+{
+ int previous = EXFAT_ENTRY_NONE;
+ int current;
+ int i;
+
+ /* check transitions between entries types */
+ for (i = 0; i < n + 1; previous = current, i++)
+ {
+ bool valid = false;
+
+ current = (i < n) ? entry[i].type : EXFAT_ENTRY_NONE;
+ switch (previous)
+ {
+ case EXFAT_ENTRY_NONE:
+ valid = (current == EXFAT_ENTRY_FILE);
+ break;
+ case EXFAT_ENTRY_FILE:
+ valid = (current == EXFAT_ENTRY_FILE_INFO);
+ break;
+ case EXFAT_ENTRY_FILE_INFO:
+ valid = (current == EXFAT_ENTRY_FILE_NAME);
+ break;
+ case EXFAT_ENTRY_FILE_NAME:
+ valid = (current == EXFAT_ENTRY_FILE_NAME ||
+ current == EXFAT_ENTRY_NONE ||
+ current >= EXFAT_ENTRY_FILE_TAIL);
+ break;
+ case EXFAT_ENTRY_FILE_TAIL ... 0xff:
+ valid = (current >= EXFAT_ENTRY_FILE_TAIL ||
+ current == EXFAT_ENTRY_NONE);
+ break;
+ }
+
+ if (!valid)
+ {
+ exfat_error("unexpected entry type %#x after %#x at %d/%d",
+ current, previous, i, n);
+ return false;
+ }
+ }
+ return true;
+}
+
+static bool check_node(const struct exfat* ef, struct exfat_node* node,
+ le16_t actual_checksum, const struct exfat_entry_meta1* meta1)
+{
+ int cluster_size = CLUSTER_SIZE(*ef->sb);
+ uint64_t clusters_heap_size =
+ (uint64_t) le32_to_cpu(ef->sb->cluster_count) * cluster_size;
+ char buffer[EXFAT_UTF8_NAME_BUFFER_MAX];
+ bool ret = true;
+
+ /*
+ Validate checksum first. If it's invalid all other fields probably
+ contain just garbage.
+ */
+ if (le16_to_cpu(actual_checksum) != le16_to_cpu(meta1->checksum))
+ {
+ exfat_get_name(node, buffer);
+ exfat_error("'%s' has invalid checksum (%#hx != %#hx)", buffer,
+ le16_to_cpu(actual_checksum), le16_to_cpu(meta1->checksum));
+ if (!EXFAT_REPAIR(invalid_node_checksum, ef, node))
+ ret = false;
+ }
+
+ /*
+ exFAT does not support sparse files but allows files with uninitialized
+ clusters. For such files valid_size means initialized data size and
+ cannot be greater than file size. See SetFileValidData() function
+ description in MSDN.
+ */
+ if (node->valid_size > node->size)
+ {
+ exfat_get_name(node, buffer);
+ exfat_error("'%s' has valid size (%"PRIu64") greater than size "
+ "(%"PRIu64")", buffer, node->valid_size, node->size);
+ ret = false;
+ }
+
+ /*
+ Empty file must have zero start cluster. Non-empty file must start
+ with a valid cluster. Directories cannot be empty (i.e. must always
+ have a valid start cluster), but we will check this later while
+ reading that directory to give user a chance to read this directory.
+ */
+ if (node->size == 0 && node->start_cluster != EXFAT_CLUSTER_FREE)
+ {
+ exfat_get_name(node, buffer);
+ exfat_error("'%s' is empty but start cluster is %#x", buffer,
+ node->start_cluster);
+ ret = false;
+ }
+ if (node->size > 0 && CLUSTER_INVALID(*ef->sb, node->start_cluster))
+ {
+ exfat_get_name(node, buffer);
+ exfat_error("'%s' points to invalid cluster %#x", buffer,
+ node->start_cluster);
+ ret = false;
+ }
+
+ /* File or directory cannot be larger than clusters heap. */
+ if (node->size > clusters_heap_size)
+ {
+ exfat_get_name(node, buffer);
+ exfat_error("'%s' is larger than clusters heap: %"PRIu64" > %"PRIu64,
+ buffer, node->size, clusters_heap_size);
+ ret = false;
+ }
+
+ /* Empty file or directory must be marked as non-contiguous. */
+ if (node->size == 0 && node->is_contiguous)
+ {
+ exfat_get_name(node, buffer);
+ exfat_error("'%s' is empty but marked as contiguous (%#hx)", buffer,
+ node->attrib);
+ ret = false;
+ }
+
+ /* Directory size must be aligned on at cluster boundary. */
+ if ((node->attrib & EXFAT_ATTRIB_DIR) && node->size % cluster_size != 0)
+ {
+ exfat_get_name(node, buffer);
+ exfat_error("'%s' directory size %"PRIu64" is not divisible by %d", buffer,
+ node->size, cluster_size);
+ ret = false;
+ }
+
+ return ret;
+}
+
+static int parse_file_entries(struct exfat* ef, struct exfat_node* node,
+ const struct exfat_entry* entries, int n)
+{
+ const struct exfat_entry_meta1* meta1;
+ const struct exfat_entry_meta2* meta2;
+ int mandatory_entries;
+
+ if (!check_entries(entries, n))
+ return -EIO;
+
+ meta1 = (const struct exfat_entry_meta1*) &entries[0];
+ if (meta1->continuations < 2)
+ {
+ exfat_error("too few continuations (%hhu)", meta1->continuations);
+ return -EIO;
+ }
+ meta2 = (const struct exfat_entry_meta2*) &entries[1];
+ if (meta2->flags & ~(EXFAT_FLAG_ALWAYS1 | EXFAT_FLAG_CONTIGUOUS))
+ {
+ exfat_error("unknown flags in meta2 (%#hhx)", meta2->flags);
+ return -EIO;
+ }
+ mandatory_entries = 2 + DIV_ROUND_UP(meta2->name_length, EXFAT_ENAME_MAX);
+ if (meta1->continuations < mandatory_entries - 1)
+ {
+ exfat_error("too few continuations (%hhu < %d)",
+ meta1->continuations, mandatory_entries - 1);
+ return -EIO;
+ }
+
+ init_node_meta1(node, meta1);
+ init_node_meta2(node, meta2);
+ init_node_name(node, entries + 2, mandatory_entries - 2);
+
+ if (!check_node(ef, node, exfat_calc_checksum(entries, n), meta1))
+ return -EIO;
+
+ return 0;
+}
+
+static int parse_file_entry(struct exfat* ef, struct exfat_node* parent,
+ struct exfat_node** node, off_t* offset, int n)
+{
+ struct exfat_entry entries[n];
+ int rc;
+
+ rc = read_entries(ef, parent, entries, n, *offset);
+ if (rc != 0)
+ return rc;
+
+ /* a new node has zero references */
+ *node = allocate_node();
+ if (*node == NULL)
+ return -ENOMEM;
+ (*node)->entry_offset = *offset;
+
+ rc = parse_file_entries(ef, *node, entries, n);
+ if (rc != 0)
+ {
+ free(*node);
+ return rc;
+ }
+
+ *offset += sizeof(struct exfat_entry[n]);
+ return 0;
+}
+
+static void decompress_upcase(uint16_t* output, const le16_t* source,
+ size_t size)
+{
+ size_t si;
+ size_t oi;
+
+ for (oi = 0; oi < EXFAT_UPCASE_CHARS; oi++)
+ output[oi] = oi;
+
+ for (si = 0, oi = 0; si < size && oi < EXFAT_UPCASE_CHARS; si++)
+ {
+ uint16_t ch = le16_to_cpu(source[si]);
+
+ if (ch == 0xffff && si + 1 < size) /* indicates a run */
+ oi += le16_to_cpu(source[++si]);
+ else
+ output[oi++] = ch;
+ }
+}
+
+/*
+ * Read one entry in a directory at offset position and build a new node
+ * structure.
+ */
+static int readdir(struct exfat* ef, struct exfat_node* parent,
+ struct exfat_node** node, off_t* offset)
+{
+ int rc;
+ struct exfat_entry entry;
+ const struct exfat_entry_meta1* meta1;
+ const struct exfat_entry_upcase* upcase;
+ const struct exfat_entry_bitmap* bitmap;
+ const struct exfat_entry_label* label;
+ uint64_t upcase_size = 0;
+ le16_t* upcase_comp = NULL;
+ le16_t label_name[EXFAT_ENAME_MAX];
+
+ for (;;)
+ {
+ rc = read_entries(ef, parent, &entry, 1, *offset);
+ if (rc != 0)
+ return rc;
+
+ switch (entry.type)
+ {
+ case EXFAT_ENTRY_FILE:
+ meta1 = (const struct exfat_entry_meta1*) &entry;
+ return parse_file_entry(ef, parent, node, offset,
+ 1 + meta1->continuations);
+
+ case EXFAT_ENTRY_UPCASE:
+ if (ef->upcase != NULL)
+ break;
+ upcase = (const struct exfat_entry_upcase*) &entry;
+ if (CLUSTER_INVALID(*ef->sb, le32_to_cpu(upcase->start_cluster)))
+ {
+ exfat_error("invalid cluster 0x%x in upcase table",
+ le32_to_cpu(upcase->start_cluster));
+ return -EIO;
+ }
+ upcase_size = le64_to_cpu(upcase->size);
+ if (upcase_size == 0 ||
+ upcase_size > EXFAT_UPCASE_CHARS * sizeof(uint16_t) ||
+ upcase_size % sizeof(uint16_t) != 0)
+ {
+ exfat_error("bad upcase table size (%"PRIu64" bytes)",
+ upcase_size);
+ return -EIO;
+ }
+ upcase_comp = malloc(upcase_size);
+ if (upcase_comp == NULL)
+ {
+ exfat_error("failed to allocate upcase table (%"PRIu64" bytes)",
+ upcase_size);
+ return -ENOMEM;
+ }
+
+ /* read compressed upcase table */
+ if (exfat_pread(ef->dev, upcase_comp, upcase_size,
+ exfat_c2o(ef, le32_to_cpu(upcase->start_cluster))) < 0)
+ {
+ free(upcase_comp);
+ exfat_error("failed to read upper case table "
+ "(%"PRIu64" bytes starting at cluster %#x)",
+ upcase_size,
+ le32_to_cpu(upcase->start_cluster));
+ return -EIO;
+ }
+
+ /* decompress upcase table */
+ ef->upcase = calloc(EXFAT_UPCASE_CHARS, sizeof(uint16_t));
+ if (ef->upcase == NULL)
+ {
+ free(upcase_comp);
+ exfat_error("failed to allocate decompressed upcase table");
+ return -ENOMEM;
+ }
+ decompress_upcase(ef->upcase, upcase_comp,
+ upcase_size / sizeof(uint16_t));
+ free(upcase_comp);
+ break;
+
+ case EXFAT_ENTRY_BITMAP:
+ bitmap = (const struct exfat_entry_bitmap*) &entry;
+ ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);
+ if (CLUSTER_INVALID(*ef->sb, ef->cmap.start_cluster))
+ {
+ exfat_error("invalid cluster 0x%x in clusters bitmap",
+ ef->cmap.start_cluster);
+ return -EIO;
+ }
+ ef->cmap.size = le32_to_cpu(ef->sb->cluster_count);
+ if (le64_to_cpu(bitmap->size) < DIV_ROUND_UP(ef->cmap.size, 8))
+ {
+ exfat_error("invalid clusters bitmap size: %"PRIu64
+ " (expected at least %u)",
+ le64_to_cpu(bitmap->size),
+ DIV_ROUND_UP(ef->cmap.size, 8));
+ return -EIO;
+ }
+ /* FIXME bitmap can be rather big, up to 512 MB */
+ ef->cmap.chunk_size = ef->cmap.size;
+ ef->cmap.chunk = malloc(BMAP_SIZE(ef->cmap.chunk_size));
+ if (ef->cmap.chunk == NULL)
+ {
+ exfat_error("failed to allocate clusters bitmap chunk "
+ "(%"PRIu64" bytes)", le64_to_cpu(bitmap->size));
+ return -ENOMEM;
+ }
+
+ if (exfat_pread(ef->dev, ef->cmap.chunk,
+ BMAP_SIZE(ef->cmap.chunk_size),
+ exfat_c2o(ef, ef->cmap.start_cluster)) < 0)
+ {
+ exfat_error("failed to read clusters bitmap "
+ "(%"PRIu64" bytes starting at cluster %#x)",
+ le64_to_cpu(bitmap->size), ef->cmap.start_cluster);
+ return -EIO;
+ }
+ break;
+
+ case EXFAT_ENTRY_LABEL:
+ label = (const struct exfat_entry_label*) &entry;
+ if (label->length > EXFAT_ENAME_MAX)
+ {
+ exfat_error("too long label (%hhu chars)", label->length);
+ return -EIO;
+ }
+ /* copy to a temporary buffer to avoid unaligned access to a
+ packed member */
+ memcpy(label_name, label->name, sizeof(label_name));
+ if (exfat_utf16_to_utf8(ef->label, label_name,
+ sizeof(ef->label), EXFAT_ENAME_MAX) != 0)
+ return -EIO;
+ break;
+
+ default:
+ if (!(entry.type & EXFAT_ENTRY_VALID))
+ break; /* deleted entry, ignore it */
+
+ exfat_error("unknown entry type %#hhx", entry.type);
+ if (!EXFAT_REPAIR(unknown_entry, ef, parent, &entry, *offset))
+ return -EIO;
+ }
+ *offset += sizeof(entry);
+ }
+ /* we never reach here */
+}
+
+int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
+{
+ off_t offset = 0;
+ int rc;
+ struct exfat_node* node;
+ struct exfat_node* current = NULL;
+
+ if (dir->is_cached)
+ return 0; /* already cached */
+
+ while ((rc = readdir(ef, dir, &node, &offset)) == 0)
+ {
+ node->parent = dir;
+ if (current != NULL)
+ {
+ current->next = node;
+ node->prev = current;
+ }
+ else
+ dir->child = node;
+
+ current = node;
+ }
+
+ if (rc != -ENOENT)
+ {
+ /* rollback */
+ for (current = dir->child; current; current = node)
+ {
+ node = current->next;
+ free(current);
+ }
+ dir->child = NULL;
+ return rc;
+ }
+
+ dir->is_cached = true;
+ return 0;
+}
+
+static void tree_attach(struct exfat_node* dir, struct exfat_node* node)
+{
+ node->parent = dir;
+ if (dir->child)
+ {
+ dir->child->prev = node;
+ node->next = dir->child;
+ }
+ dir->child = node;
+}
+
+static void tree_detach(struct exfat_node* node)
+{
+ if (node->prev)
+ node->prev->next = node->next;
+ else /* this is the first node in the list */
+ node->parent->child = node->next;
+ if (node->next)
+ node->next->prev = node->prev;
+ node->parent = NULL;
+ node->prev = NULL;
+ node->next = NULL;
+}
+
+static void reset_cache(struct exfat* ef, struct exfat_node* node)
+{
+ char buffer[EXFAT_UTF8_NAME_BUFFER_MAX];
+
+ while (node->child)
+ {
+ struct exfat_node* p = node->child;
+ reset_cache(ef, p);
+ tree_detach(p);
+ free(p);
+ }
+ node->is_cached = false;
+ if (node->references != 0)
+ {
+ exfat_get_name(node, buffer);
+ exfat_warn("non-zero reference counter (%d) for '%s'",
+ node->references, buffer);
+ }
+ if (node != ef->root && node->is_dirty)
+ {
+ exfat_get_name(node, buffer);
+ exfat_bug("node '%s' is dirty", buffer);
+ }
+ while (node->references)
+ exfat_put_node(ef, node);
+}
+
+void exfat_reset_cache(struct exfat* ef)
+{
+ reset_cache(ef, ef->root);
+}
+
+int exfat_flush_node(struct exfat* ef, struct exfat_node* node)
+{
+ struct exfat_entry entries[1 + node->continuations];
+ struct exfat_entry_meta1* meta1 = (struct exfat_entry_meta1*) &entries[0];
+ struct exfat_entry_meta2* meta2 = (struct exfat_entry_meta2*) &entries[1];
+ int rc;
+ le16_t edate, etime;
+
+ if (!node->is_dirty)
+ return 0; /* no need to flush */
+
+ if (ef->ro)
+ exfat_bug("unable to flush node to read-only FS");
+
+ if (node->parent == NULL)
+ return 0; /* do not flush unlinked node */
+
+ rc = read_entries(ef, node->parent, entries, 1 + node->continuations,
+ node->entry_offset);
+ if (rc != 0)
+ return rc;
+ if (!check_entries(entries, 1 + node->continuations))
+ return -EIO;
+
+ meta1->attrib = cpu_to_le16(node->attrib);
+ exfat_unix2exfat(node->mtime, &edate, &etime,
+ &meta1->mtime_cs, &meta1->mtime_tzo);
+ meta1->mdate = edate;
+ meta1->mtime = etime;
+ exfat_unix2exfat(node->atime, &edate, &etime,
+ NULL, &meta1->atime_tzo);
+ meta1->adate = edate;
+ meta1->atime = etime;
+ meta2->valid_size = cpu_to_le64(node->valid_size);
+ meta2->size = cpu_to_le64(node->size);
+ meta2->start_cluster = cpu_to_le32(node->start_cluster);
+ meta2->flags = EXFAT_FLAG_ALWAYS1;
+ /* empty files must not be marked as contiguous */
+ if (node->size != 0 && node->is_contiguous)
+ meta2->flags |= EXFAT_FLAG_CONTIGUOUS;
+ /* name hash remains unchanged, no need to recalculate it */
+
+ meta1->checksum = exfat_calc_checksum(entries, 1 + node->continuations);
+ rc = write_entries(ef, node->parent, entries, 1 + node->continuations,
+ node->entry_offset);
+ if (rc != 0)
+ return rc;
+
+ node->is_dirty = false;
+ return exfat_flush(ef);
+}
+
+static int erase_entries(struct exfat* ef, struct exfat_node* dir, int n,
+ off_t offset)
+{
+ struct exfat_entry entries[n];
+ int rc;
+ int i;
+
+ rc = read_entries(ef, dir, entries, n, offset);
+ if (rc != 0)
+ return rc;
+ for (i = 0; i < n; i++)
+ entries[i].type &= ~EXFAT_ENTRY_VALID;
+ return write_entries(ef, dir, entries, n, offset);
+}
+
+static int erase_node(struct exfat* ef, struct exfat_node* node)
+{
+ int rc;
+
+ exfat_get_node(node->parent);
+ rc = erase_entries(ef, node->parent, 1 + node->continuations,
+ node->entry_offset);
+ if (rc != 0)
+ {
+ exfat_put_node(ef, node->parent);
+ return rc;
+ }
+ rc = exfat_flush_node(ef, node->parent);
+ exfat_put_node(ef, node->parent);
+ return rc;
+}
+
+static int shrink_directory(struct exfat* ef, struct exfat_node* dir,
+ off_t deleted_offset)
+{
+ const struct exfat_node* node;
+ const struct exfat_node* last_node;
+ uint64_t entries = 0;
+ uint64_t new_size;
+
+ if (!(dir->attrib & EXFAT_ATTRIB_DIR))
+ exfat_bug("attempted to shrink a file");
+ if (!dir->is_cached)
+ exfat_bug("attempted to shrink uncached directory");
+
+ for (last_node = node = dir->child; node; node = node->next)
+ {
+ if (deleted_offset < node->entry_offset)
+ {
+ /* there are other entries after the removed one, no way to shrink
+ this directory */
+ return 0;
+ }
+ if (last_node->entry_offset < node->entry_offset)
+ last_node = node;
+ }
+
+ if (last_node)
+ {
+ /* offset of the last entry */
+ entries += last_node->entry_offset / sizeof(struct exfat_entry);
+ /* two subentries with meta info */
+ entries += 2;
+ /* subentries with file name */
+ entries += DIV_ROUND_UP(exfat_utf16_length(last_node->name),
+ EXFAT_ENAME_MAX);
+ }
+
+ new_size = DIV_ROUND_UP(entries * sizeof(struct exfat_entry),
+ CLUSTER_SIZE(*ef->sb)) * CLUSTER_SIZE(*ef->sb);
+ if (new_size == 0) /* directory always has at least 1 cluster */
+ new_size = CLUSTER_SIZE(*ef->sb);
+ if (new_size == dir->size)
+ return 0;
+ return exfat_truncate(ef, dir, new_size, true);
+}
+
+static int delete(struct exfat* ef, struct exfat_node* node)
+{
+ struct exfat_node* parent = node->parent;
+ off_t deleted_offset = node->entry_offset;
+ int rc;
+
+ exfat_get_node(parent);
+ rc = erase_node(ef, node);
+ if (rc != 0)
+ {
+ exfat_put_node(ef, parent);
+ return rc;
+ }
+ tree_detach(node);
+ rc = shrink_directory(ef, parent, deleted_offset);
+ node->is_unlinked = true;
+ if (rc != 0)
+ {
+ exfat_flush_node(ef, parent);
+ exfat_put_node(ef, parent);
+ return rc;
+ }
+ exfat_update_mtime(parent);
+ rc = exfat_flush_node(ef, parent);
+ exfat_put_node(ef, parent);
+ return rc;
+}
+
+int exfat_unlink(struct exfat* ef, struct exfat_node* node)
+{
+ if (node->attrib & EXFAT_ATTRIB_DIR)
+ return -EISDIR;
+ return delete(ef, node);
+}
+
+int exfat_rmdir(struct exfat* ef, struct exfat_node* node)
+{
+ int rc;
+
+ if (!(node->attrib & EXFAT_ATTRIB_DIR))
+ return -ENOTDIR;
+ /* check that directory is empty */
+ rc = exfat_cache_directory(ef, node);
+ if (rc != 0)
+ return rc;
+ if (node->child)
+ return -ENOTEMPTY;
+ return delete(ef, node);
+}
+
+static int check_slot(struct exfat* ef, struct exfat_node* dir, off_t offset,
+ int n)
+{
+ struct exfat_entry entries[n];
+ int rc;
+ int i;
+
+ /* Root directory contains entries, that don't have any nodes associated
+ with them (clusters bitmap, upper case table, label). We need to be
+ careful not to overwrite them. */
+ if (dir != ef->root)
+ return 0;
+
+ rc = read_entries(ef, dir, entries, n, offset);
+ if (rc != 0)
+ return rc;
+ for (i = 0; i < n; i++)
+ if (entries[i].type & EXFAT_ENTRY_VALID)
+ return -EINVAL;
+ return 0;
+}
+
+static int find_slot(struct exfat* ef, struct exfat_node* dir,
+ off_t* offset, int n)
+{
+ bitmap_t* dmap;
+ struct exfat_node* p;
+ size_t i;
+ int contiguous = 0;
+
+ if (!dir->is_cached)
+ exfat_bug("directory is not cached");
+
+ /* build a bitmap of valid entries in the directory */
+ dmap = calloc(BMAP_SIZE(dir->size / sizeof(struct exfat_entry)),
+ sizeof(bitmap_t));
+ if (dmap == NULL)
+ {
+ exfat_error("failed to allocate directory bitmap (%"PRIu64")",
+ dir->size / sizeof(struct exfat_entry));
+ return -ENOMEM;
+ }
+ for (p = dir->child; p != NULL; p = p->next)
+ for (i = 0; i < 1u + p->continuations; i++)
+ BMAP_SET(dmap, p->entry_offset / sizeof(struct exfat_entry) + i);
+
+ /* find a slot in the directory entries bitmap */
+ for (i = 0; i < dir->size / sizeof(struct exfat_entry); i++)
+ {
+ if (BMAP_GET(dmap, i) == 0)
+ {
+ if (contiguous++ == 0)
+ *offset = (off_t) i * sizeof(struct exfat_entry);
+ if (contiguous == n)
+ {
+ int rc;
+
+ /* suitable slot is found, check that it's not occupied */
+ rc = check_slot(ef, dir, *offset, n);
+ if (rc == -EINVAL)
+ {
+ /* slot at (i-n) is occupied, go back and check (i-n+1) */
+ i -= contiguous - 1;
+ contiguous = 0;
+ }
+ else
+ {
+ /* slot is free or an error occurred */
+ free(dmap);
+ return rc;
+ }
+ }
+ }
+ else
+ contiguous = 0;
+ }
+ free(dmap);
+
+ /* no suitable slots found, extend the directory */
+ if (contiguous == 0)
+ *offset = dir->size;
+ return exfat_truncate(ef, dir,
+ ROUND_UP(dir->size + sizeof(struct exfat_entry[n - contiguous]),
+ CLUSTER_SIZE(*ef->sb)),
+ true);
+}
+
+static int commit_entry(struct exfat* ef, struct exfat_node* dir,
+ const le16_t* name, off_t offset, uint16_t attrib)
+{
+ struct exfat_node* node;
+ const size_t name_length = exfat_utf16_length(name);
+ const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
+ struct exfat_entry entries[2 + name_entries];
+ struct exfat_entry_meta1* meta1 = (struct exfat_entry_meta1*) &entries[0];
+ struct exfat_entry_meta2* meta2 = (struct exfat_entry_meta2*) &entries[1];
+ int i;
+ int rc;
+ le16_t edate, etime;
+
+ memset(entries, 0, sizeof(struct exfat_entry[2]));
+
+ meta1->type = EXFAT_ENTRY_FILE;
+ meta1->continuations = 1 + name_entries;
+ meta1->attrib = cpu_to_le16(attrib);
+ exfat_unix2exfat(time(NULL), &edate, &etime,
+ &meta1->crtime_cs, &meta1->crtime_tzo);
+ meta1->adate = meta1->mdate = meta1->crdate = edate;
+ meta1->atime = meta1->mtime = meta1->crtime = etime;
+ meta1->mtime_cs = meta1->crtime_cs; /* there is no atime_cs */
+ meta1->atime_tzo = meta1->mtime_tzo = meta1->crtime_tzo;
+
+ meta2->type = EXFAT_ENTRY_FILE_INFO;
+ meta2->flags = EXFAT_FLAG_ALWAYS1;
+ meta2->name_length = name_length;
+ meta2->name_hash = exfat_calc_name_hash(ef, name, name_length);
+ meta2->start_cluster = cpu_to_le32(EXFAT_CLUSTER_FREE);
+
+ for (i = 0; i < name_entries; i++)
+ {
+ struct exfat_entry_name* name_entry;
+
+ name_entry = (struct exfat_entry_name*) &entries[2 + i];
+ name_entry->type = EXFAT_ENTRY_FILE_NAME;
+ name_entry->__unknown = 0;
+ memcpy(name_entry->name, name + i * EXFAT_ENAME_MAX,
+ EXFAT_ENAME_MAX * sizeof(le16_t));
+ }
+
+ meta1->checksum = exfat_calc_checksum(entries, 2 + name_entries);
+ rc = write_entries(ef, dir, entries, 2 + name_entries, offset);
+ if (rc != 0)
+ return rc;
+
+ node = allocate_node();
+ if (node == NULL)
+ return -ENOMEM;
+ node->entry_offset = offset;
+ memcpy(node->name, name, name_length * sizeof(le16_t));
+ init_node_meta1(node, meta1);
+ init_node_meta2(node, meta2);
+
+ tree_attach(dir, node);
+ return 0;
+}
+
+static int create(struct exfat* ef, const char* path, uint16_t attrib)
+{
+ struct exfat_node* dir;
+ struct exfat_node* existing;
+ off_t offset = -1;
+ le16_t name[EXFAT_NAME_MAX + 1];
+ int rc;
+
+ rc = exfat_split(ef, &dir, &existing, name, path);
+ if (rc != 0)
+ return rc;
+ if (existing != NULL)
+ {
+ exfat_put_node(ef, existing);
+ exfat_put_node(ef, dir);
+ return -EEXIST;
+ }
+
+ rc = find_slot(ef, dir, &offset,
+ 2 + DIV_ROUND_UP(exfat_utf16_length(name), EXFAT_ENAME_MAX));
+ if (rc != 0)
+ {
+ exfat_put_node(ef, dir);
+ return rc;
+ }
+ rc = commit_entry(ef, dir, name, offset, attrib);
+ if (rc != 0)
+ {
+ exfat_put_node(ef, dir);
+ return rc;
+ }
+ exfat_update_mtime(dir);
+ rc = exfat_flush_node(ef, dir);
+ exfat_put_node(ef, dir);
+ return rc;
+}
+
+int exfat_mknod(struct exfat* ef, const char* path)
+{
+ return create(ef, path, EXFAT_ATTRIB_ARCH);
+}
+
+int exfat_mkdir(struct exfat* ef, const char* path)
+{
+ int rc;
+ struct exfat_node* node;
+
+ rc = create(ef, path, EXFAT_ATTRIB_DIR);
+ if (rc != 0)
+ return rc;
+ rc = exfat_lookup(ef, &node, path);
+ if (rc != 0)
+ return 0;
+ /* directories always have at least one cluster */
+ rc = exfat_truncate(ef, node, CLUSTER_SIZE(*ef->sb), true);
+ if (rc != 0)
+ {
+ delete(ef, node);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ rc = exfat_flush_node(ef, node);
+ if (rc != 0)
+ {
+ delete(ef, node);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ exfat_put_node(ef, node);
+ return 0;
+}
+
+static int rename_entry(struct exfat* ef, struct exfat_node* dir,
+ struct exfat_node* node, const le16_t* name, off_t new_offset)
+{
+ const size_t name_length = exfat_utf16_length(name);
+ const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
+ struct exfat_entry entries[2 + name_entries];
+ struct exfat_entry_meta1* meta1 = (struct exfat_entry_meta1*) &entries[0];
+ struct exfat_entry_meta2* meta2 = (struct exfat_entry_meta2*) &entries[1];
+ int rc;
+ int i;
+
+ rc = read_entries(ef, node->parent, entries, 2, node->entry_offset);
+ if (rc != 0)
+ return rc;
+
+ meta1->continuations = 1 + name_entries;
+ meta2->name_length = name_length;
+ meta2->name_hash = exfat_calc_name_hash(ef, name, name_length);
+
+ rc = erase_node(ef, node);
+ if (rc != 0)
+ return rc;
+
+ node->entry_offset = new_offset;
+ node->continuations = 1 + name_entries;
+
+ for (i = 0; i < name_entries; i++)
+ {
+ struct exfat_entry_name* name_entry;
+
+ name_entry = (struct exfat_entry_name*) &entries[2 + i];
+ name_entry->type = EXFAT_ENTRY_FILE_NAME;
+ name_entry->__unknown = 0;
+ memcpy(name_entry->name, name + i * EXFAT_ENAME_MAX,
+ EXFAT_ENAME_MAX * sizeof(le16_t));
+ }
+
+ meta1->checksum = exfat_calc_checksum(entries, 2 + name_entries);
+ rc = write_entries(ef, dir, entries, 2 + name_entries, new_offset);
+ if (rc != 0)
+ return rc;
+
+ memcpy(node->name, name, (EXFAT_NAME_MAX + 1) * sizeof(le16_t));
+ tree_detach(node);
+ tree_attach(dir, node);
+ return 0;
+}
+
+int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
+{
+ struct exfat_node* node;
+ struct exfat_node* existing;
+ struct exfat_node* dir;
+ off_t offset = -1;
+ le16_t name[EXFAT_NAME_MAX + 1];
+ int rc;
+
+ rc = exfat_lookup(ef, &node, old_path);
+ if (rc != 0)
+ return rc;
+
+ rc = exfat_split(ef, &dir, &existing, name, new_path);
+ if (rc != 0)
+ {
+ exfat_put_node(ef, node);
+ return rc;
+ }
+
+ /* check that target is not a subdirectory of the source */
+ if (node->attrib & EXFAT_ATTRIB_DIR)
+ {
+ struct exfat_node* p;
+
+ for (p = dir; p; p = p->parent)
+ if (node == p)
+ {
+ if (existing != NULL)
+ exfat_put_node(ef, existing);
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ return -EINVAL;
+ }
+ }
+
+ if (existing != NULL)
+ {
+ /* remove target if it's not the same node as source */
+ if (existing != node)
+ {
+ if (existing->attrib & EXFAT_ATTRIB_DIR)
+ {
+ if (node->attrib & EXFAT_ATTRIB_DIR)
+ rc = exfat_rmdir(ef, existing);
+ else
+ rc = -ENOTDIR;
+ }
+ else
+ {
+ if (!(node->attrib & EXFAT_ATTRIB_DIR))
+ rc = exfat_unlink(ef, existing);
+ else
+ rc = -EISDIR;
+ }
+ exfat_put_node(ef, existing);
+ if (rc != 0)
+ {
+ /* free clusters even if something went wrong; otherwise they
+ will be just lost */
+ exfat_cleanup_node(ef, existing);
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ rc = exfat_cleanup_node(ef, existing);
+ if (rc != 0)
+ {
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ }
+ else
+ exfat_put_node(ef, existing);
+ }
+
+ rc = find_slot(ef, dir, &offset,
+ 2 + DIV_ROUND_UP(exfat_utf16_length(name), EXFAT_ENAME_MAX));
+ if (rc != 0)
+ {
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ rc = rename_entry(ef, dir, node, name, offset);
+ if (rc != 0)
+ {
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ rc = exfat_flush_node(ef, dir);
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ /* node itself is not marked as dirty, no need to flush it */
+ return rc;
+}
+
+void exfat_utimes(struct exfat_node* node, const struct timespec tv[2])
+{
+ node->atime = tv[0].tv_sec;
+ node->mtime = tv[1].tv_sec;
+ node->is_dirty = true;
+}
+
+void exfat_update_atime(struct exfat_node* node)
+{
+ node->atime = time(NULL);
+ node->is_dirty = true;
+}
+
+void exfat_update_mtime(struct exfat_node* node)
+{
+ node->mtime = time(NULL);
+ node->is_dirty = true;
+}
+
+const char* exfat_get_label(struct exfat* ef)
+{
+ return ef->label;
+}
+
+static int find_label(struct exfat* ef, off_t* offset)
+{
+ struct exfat_entry entry;
+ int rc;
+
+ for (*offset = 0; ; *offset += sizeof(entry))
+ {
+ rc = read_entries(ef, ef->root, &entry, 1, *offset);
+ if (rc != 0)
+ return rc;
+
+ if (entry.type == EXFAT_ENTRY_LABEL)
+ return 0;
+ }
+}
+
+int exfat_set_label(struct exfat* ef, const char* label)
+{
+ le16_t label_utf16[EXFAT_ENAME_MAX + 1];
+ int rc;
+ off_t offset;
+ struct exfat_entry_label entry;
+
+ memset(label_utf16, 0, sizeof(label_utf16));
+ rc = exfat_utf8_to_utf16(label_utf16, label, EXFAT_ENAME_MAX + 1,
+ strlen(label));
+ if (rc != 0)
+ return rc;
+
+ rc = find_label(ef, &offset);
+ if (rc == -ENOENT)
+ rc = find_slot(ef, ef->root, &offset, 1);
+ if (rc != 0)
+ return rc;
+
+ entry.type = EXFAT_ENTRY_LABEL;
+ entry.length = exfat_utf16_length(label_utf16);
+ memcpy(entry.name, label_utf16, sizeof(entry.name));
+ if (entry.length == 0)
+ entry.type ^= EXFAT_ENTRY_VALID;
+
+ rc = write_entries(ef, ef->root, (struct exfat_entry*) &entry, 1, offset);
+ if (rc != 0)
+ return rc;
+
+ strcpy(ef->label, label);
+ return 0;
+}