Move library source into src sub-directory

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 374 insertions, 0 deletions

diff --git a/lib/sqfs/src/data_reader.c b/lib/sqfs/src/data_reader.c
new file mode 100644
index 0000000..3f0cd74
--- /dev/null
+++ b/lib/sqfs/src/data_reader.c
@@ -0,0 +1,374 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * data_reader.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "config.h"
+
+#include "sqfs/data_reader.h"
+#include "sqfs/compressor.h"
+#include "sqfs/frag_table.h"
+#include "sqfs/block.h"
+#include "sqfs/error.h"
+#include "sqfs/table.h"
+#include "sqfs/inode.h"
+#include "sqfs/io.h"
+#include "util/util.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+struct sqfs_data_reader_t {
+	sqfs_object_t obj;
+
+	sqfs_frag_table_t *frag_tbl;
+	sqfs_compressor_t *cmp;
+	sqfs_file_t *file;
+
+	sqfs_u8 *data_block;
+	size_t data_blk_size;
+	sqfs_u64 current_block;
+
+	sqfs_u8 *frag_block;
+	size_t frag_blk_size;
+	sqfs_u32 current_frag_index;
+	sqfs_u32 block_size;
+
+	sqfs_u8 scratch[];
+};
+
+static int get_block(sqfs_data_reader_t *data, sqfs_u64 off, sqfs_u32 size,
+		     sqfs_u32 max_size, size_t *out_sz, sqfs_u8 **out)
+{
+	sqfs_u32 on_disk_size;
+	sqfs_s32 ret;
+	int err;
+
+	*out = alloc_array(1, max_size);
+	*out_sz = max_size;
+
+	if (*out == NULL) {
+		err = SQFS_ERROR_ALLOC;
+		goto fail;
+	}
+
+	if (SQFS_IS_SPARSE_BLOCK(size))
+		return 0;
+
+	on_disk_size = SQFS_ON_DISK_BLOCK_SIZE(size);
+
+	if (on_disk_size > max_size) {
+		err = SQFS_ERROR_OVERFLOW;
+		goto fail;
+	}
+
+	if (SQFS_IS_BLOCK_COMPRESSED(size)) {
+		err = data->file->read_at(data->file, off,
+					  data->scratch, on_disk_size);
+		if (err)
+			goto fail;
+
+		ret = data->cmp->do_block(data->cmp, data->scratch,
+					  on_disk_size, *out, max_size);
+		if (ret <= 0) {
+			err = ret < 0 ? ret : SQFS_ERROR_OVERFLOW;
+			goto fail;
+		}
+
+		*out_sz = ret;
+	} else {
+		err = data->file->read_at(data->file, off,
+					  *out, on_disk_size);
+		if (err)
+			goto fail;
+
+		*out_sz = on_disk_size;
+	}
+
+	return 0;
+fail:
+	free(*out);
+	*out = NULL;
+	*out_sz = 0;
+	return err;
+}
+
+static int precache_data_block(sqfs_data_reader_t *data, sqfs_u64 location,
+			       sqfs_u32 size)
+{
+	if (data->data_block != NULL && data->current_block == location)
+		return 0;
+
+	free(data->data_block);
+	data->current_block = location;
+
+	return get_block(data, location, size, data->block_size,
+			 &data->data_blk_size, &data->data_block);
+}
+
+static int precache_fragment_block(sqfs_data_reader_t *data, size_t idx)
+{
+	sqfs_fragment_t ent;
+	int ret;
+
+	if (data->frag_block != NULL && idx == data->current_frag_index)
+		return 0;
+
+	ret = sqfs_frag_table_lookup(data->frag_tbl, idx, &ent);
+	if (ret != 0)
+		return ret;
+
+	free(data->frag_block);
+	data->current_frag_index = idx;
+
+	return get_block(data, ent.start_offset, ent.size, data->block_size,
+			 &data->frag_blk_size, &data->frag_block);
+}
+
+static void data_reader_destroy(sqfs_object_t *obj)
+{
+	sqfs_data_reader_t *data = (sqfs_data_reader_t *)obj;
+
+	sqfs_drop(data->cmp);
+	sqfs_drop(data->file);
+	sqfs_drop(data->frag_tbl);
+	free(data->data_block);
+	free(data->frag_block);
+	free(data);
+}
+
+static sqfs_object_t *data_reader_copy(const sqfs_object_t *obj)
+{
+	const sqfs_data_reader_t *data = (const sqfs_data_reader_t *)obj;
+	sqfs_data_reader_t *copy;
+
+	copy = alloc_flex(sizeof(*data), 1, data->block_size);
+	if (copy == NULL)
+		return NULL;
+
+	memcpy(copy, data, sizeof(*data) + data->block_size);
+
+	copy->frag_tbl = sqfs_copy(data->frag_tbl);
+	if (copy->frag_tbl == NULL)
+		goto fail_ftbl;
+
+	if (data->data_block != NULL) {
+		copy->data_block = malloc(data->data_blk_size);
+		if (copy->data_block == NULL)
+			goto fail_dblk;
+
+		memcpy(copy->data_block, data->data_block,
+		       data->data_blk_size);
+	}
+
+	if (copy->frag_block != NULL) {
+		copy->frag_block = malloc(copy->frag_blk_size);
+		if (copy->frag_block == NULL)
+			goto fail_fblk;
+
+		memcpy(copy->frag_block, data->frag_block,
+		       data->frag_blk_size);
+	}
+
+	/* duplicate references */
+	copy->file = sqfs_grab(copy->file);
+	copy->cmp = sqfs_grab(copy->cmp);
+	return (sqfs_object_t *)copy;
+fail_fblk:
+	free(copy->data_block);
+fail_dblk:
+	sqfs_drop(copy->frag_tbl);
+fail_ftbl:
+	free(copy);
+	return NULL;
+}
+
+sqfs_data_reader_t *sqfs_data_reader_create(sqfs_file_t *file,
+					    size_t block_size,
+					    sqfs_compressor_t *cmp,
+					    sqfs_u32 flags)
+{
+	sqfs_data_reader_t *data;
+
+	if (flags != 0)
+		return NULL;
+
+	data = alloc_flex(sizeof(*data), 1, block_size);
+	if (data == NULL)
+		return NULL;
+
+	sqfs_object_init(data, data_reader_destroy, data_reader_copy);
+
+	data->frag_tbl = sqfs_frag_table_create(0);
+	if (data->frag_tbl == NULL) {
+		free(data);
+		return NULL;
+	}
+
+	data->file = sqfs_grab(file);
+	data->block_size = block_size;
+	data->cmp = sqfs_grab(cmp);
+	return data;
+}
+
+int sqfs_data_reader_load_fragment_table(sqfs_data_reader_t *data,
+					 const sqfs_super_t *super)
+{
+	int ret;
+
+	free(data->frag_block);
+	data->frag_block = NULL;
+	data->current_frag_index = 0;
+
+	ret = sqfs_frag_table_read(data->frag_tbl, data->file,
+				   super, data->cmp);
+	if (ret != 0)
+		return ret;
+
+	data->current_frag_index = sqfs_frag_table_get_size(data->frag_tbl);
+	return 0;
+}
+
+int sqfs_data_reader_get_block(sqfs_data_reader_t *data,
+			       const sqfs_inode_generic_t *inode,
+			       size_t index, size_t *size, sqfs_u8 **out)
+{
+	size_t i, unpacked_size;
+	sqfs_u64 off, filesz;
+
+	sqfs_inode_get_file_block_start(inode, &off);
+	sqfs_inode_get_file_size(inode, &filesz);
+
+	if (index >= sqfs_inode_get_file_block_count(inode))
+		return SQFS_ERROR_OUT_OF_BOUNDS;
+
+	for (i = 0; i < index; ++i) {
+		off += SQFS_ON_DISK_BLOCK_SIZE(inode->extra[i]);
+		filesz -= data->block_size;
+	}
+
+	unpacked_size = filesz < data->block_size ? filesz : data->block_size;
+
+	return get_block(data, off, inode->extra[index],
+			 unpacked_size, size, out);
+}
+
+int sqfs_data_reader_get_fragment(sqfs_data_reader_t *data,
+				  const sqfs_inode_generic_t *inode,
+				  size_t *size, sqfs_u8 **out)
+{
+	sqfs_u32 frag_idx, frag_off, frag_sz;
+	size_t block_count;
+	sqfs_u64 filesz;
+	int err;
+
+	sqfs_inode_get_file_size(inode, &filesz);
+	sqfs_inode_get_frag_location(inode, &frag_idx, &frag_off);
+	*size = 0;
+	*out = NULL;
+
+	block_count = sqfs_inode_get_file_block_count(inode);
+
+	if (block_count > (UINT64_MAX / data->block_size))
+		return SQFS_ERROR_OVERFLOW;
+
+	if ((sqfs_u64)block_count * data->block_size >= filesz)
+		return 0;
+
+	frag_sz = filesz % data->block_size;
+
+	err = precache_fragment_block(data, frag_idx);
+	if (err)
+		return err;
+
+	if (frag_off + frag_sz > data->block_size)
+		return SQFS_ERROR_OUT_OF_BOUNDS;
+
+	*out = alloc_array(1, frag_sz);
+	if (*out == NULL)
+		return SQFS_ERROR_ALLOC;
+
+	*size = frag_sz;
+	memcpy(*out, (char *)data->frag_block + frag_off, frag_sz);
+	return 0;
+}
+
+sqfs_s32 sqfs_data_reader_read(sqfs_data_reader_t *data,
+			       const sqfs_inode_generic_t *inode,
+			       sqfs_u64 offset, void *buffer, sqfs_u32 size)
+{
+	sqfs_u32 frag_idx, frag_off, diff, total = 0;
+	size_t i, block_count;
+	sqfs_u64 off, filesz;
+	char *ptr;
+	int err;
+
+	if (size >= 0x7FFFFFFF)
+		size = 0x7FFFFFFE;
+
+	/* work out file location and size */
+	sqfs_inode_get_file_size(inode, &filesz);
+	sqfs_inode_get_frag_location(inode, &frag_idx, &frag_off);
+	sqfs_inode_get_file_block_start(inode, &off);
+	block_count = sqfs_inode_get_file_block_count(inode);
+
+	if (offset >= filesz)
+		return 0;
+
+	if ((filesz - offset) < (sqfs_u64)size)
+		size = filesz - offset;
+
+	if (size == 0)
+		return 0;
+
+	/* find location of the first block */
+	for (i = 0; offset > data->block_size && i < block_count; ++i) {
+		off += SQFS_ON_DISK_BLOCK_SIZE(inode->extra[i]);
+		offset -= data->block_size;
+	}
+
+	/* copy data from blocks */
+	while (i < block_count && size > 0) {
+		diff = data->block_size - offset;
+		if (size < diff)
+			diff = size;
+
+		if (SQFS_IS_SPARSE_BLOCK(inode->extra[i])) {
+			memset(buffer, 0, diff);
+		} else {
+			err = precache_data_block(data, off, inode->extra[i]);
+			if (err)
+				return err;
+
+			memcpy(buffer, (char *)data->data_block + offset, diff);
+			off += SQFS_ON_DISK_BLOCK_SIZE(inode->extra[i]);
+		}
+
+		++i;
+		offset = 0;
+		size -= diff;
+		total += diff;
+		buffer = (char *)buffer + diff;
+	}
+
+	/* copy from fragment */
+	if (size > 0) {
+		err = precache_fragment_block(data, frag_idx);
+		if (err)
+			return err;
+
+		if ((frag_off + offset) >= data->frag_blk_size)
+			return SQFS_ERROR_OUT_OF_BOUNDS;
+
+		if ((data->frag_blk_size - (frag_off + offset)) < size)
+			return SQFS_ERROR_OUT_OF_BOUNDS;
+
+		ptr = (char *)data->frag_block + frag_off + offset;
+		memcpy(buffer, ptr, size);
+		total += size;
+	}
+
+	return total;
+}