GCC Code Coverage Report

Line	Branch	Exec	Source
1			/* GATE PROJECT LICENSE:
2			+----------------------------------------------------------------------------+
3			| Copyright(c) 2018-2026, Stefan Meislinger |
4			| All rights reserved. |
5			| |
6			| Redistribution and use in source and binary forms, with or without |
7			| modification, are permitted provided that the following conditions are met:|
8			| |
9			| 1. Redistributions of source code must retain the above copyright notice, |
10			| this list of conditions and the following disclaimer. |
11			| 2. Redistributions in binary form must reproduce the above copyright |
12			| notice, this list of conditions and the following disclaimer in the |
13			| documentation and/or other materials provided with the distribution. |
14			| |
15			| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"|
16			| AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
17			| IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
18			| ARE DISCLAIMED.IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
19			| LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
20			| CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
21			| SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
22			| INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
23			| CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
24			| ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
25			| THE POSSIBILITY OF SUCH DAMAGE. |
26			+----------------------------------------------------------------------------+
27			*/
28
29			#include "gate/tech/filesystems.h"
30			#include "gate/results.h"
31
32		✗	gate_result_t gate_filesystem_read_bootsector(gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t* bootsect)
33			{
34			gate_result_t ret;
35			char buffer[512];
36		✗	gate_size_t received = 0;
37
38			do
39			{
40		✗	ret = gate_stream_seek(blockstream, 0, GATE_STREAM_SEEK_BEGIN, NULL);
41		✗	GATE_BREAK_IF_FAILED(ret);
42
43		✗	ret = gate_stream_read(blockstream, buffer, 512, &received);
44		✗	GATE_BREAK_IF_FAILED(ret);
45
46		✗	gate_mem_copy(bootsect, &buffer[0], 512);
47			} while (0);
48
49		✗	return ret;
50			}
51
52		✗	static unsigned get_total_clusters(gate_filesystem_fat_bootsect_t const* bootsect)
53			{
54		✗	return (unsigned)bootsect->bpb.total_sectors / (unsigned)bootsect->bpb.sectors_per_cluster;
55			}
56
57		✗	static unsigned get_first_root_dir_sector(gate_filesystem_fat_bootsect_t const* bootsect)
58			{
59		✗	return (unsigned)bootsect->bpb.reserved_sectors + (unsigned)bootsect->bpb.sectors_per_fat * (unsigned)bootsect->bpb.number_of_fats;
60			}
61
62		✗	static unsigned get_root_dir_sectors(gate_filesystem_fat_bootsect_t const* bootsect)
63			{
64		✗	return (bootsect->bpb.root_entries * 32 + (unsigned)bootsect->bpb.bytes_per_sector - 1)
65		✗	/ (unsigned)bootsect->bpb.bytes_per_sector;
66			}
67
68		✗	static unsigned get_total_data_sectors(gate_filesystem_fat_bootsect_t const* bootsect)
69			{
70		✗	unsigned const first_root_dir_sector = get_first_root_dir_sector(bootsect);
71		✗	unsigned const root_dir_sectors = get_root_dir_sectors(bootsect);
72		✗	return (unsigned)bootsect->bpb.total_sectors - first_root_dir_sector - root_dir_sectors;
73			}
74
75		✗	static unsigned get_total_data_clusters(gate_filesystem_fat_bootsect_t const* bootsect)
76			{
77		✗	return get_total_data_sectors(bootsect) / (unsigned)bootsect->bpb.sectors_per_cluster;
78			}
79
80		✗	static unsigned get_root_dir_sectors_count(gate_filesystem_fat_bootsect_t const* bootsect)
81			{
82		✗	unsigned const sector_size = bootsect->bpb.bytes_per_sector;
83		✗	return (bootsect->bpb.root_entries * 32 + sector_size - 1) / sector_size;
84			}
85
86		✗	static unsigned get_data_cluster_sector(gate_filesystem_fat_bootsect_t const* bootsect, unsigned cluster_num)
87			{
88			/* notice: our cluster_num starts with "0" (FAT clusters start with "2") */
89		✗	unsigned const root_dir_sectors = get_root_dir_sectors_count(bootsect);
90		✗	unsigned const first_data_cluster_sector = get_first_root_dir_sector(bootsect) + root_dir_sectors;
91		✗	return first_data_cluster_sector + cluster_num * (unsigned)bootsect->bpb.sectors_per_cluster;
92			}
93
94		✗	static unsigned get_fat_type(gate_filesystem_fat_bootsect_t const* bootsect)
95			{
96		✗	gate_size_t total_clusters = bootsect->bpb.total_sectors / bootsect->bpb.sectors_per_cluster;
97
98		✗	if (total_clusters < 4085)
99			{
100		✗	return 12;
101			}
102		✗	else if (total_clusters < 65525)
103			{
104		✗	return 16;
105			}
106			else
107			{
108		✗	return 32;
109			}
110			}
111
112		✗	static gate_result_t read_sector(gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t const* bootsect, unsigned sector, char* out_buffer)
113			{
114		✗	const gate_size_t sector_length = bootsect->bpb.bytes_per_sector;
115		✗	const gate_int64_t pos = (gate_int64_t)sector * (gate_int64_t)sector_length;
116			gate_size_t length_returned;
117		✗	gate_result_t result = gate_stream_seek(blockstream, pos, GATE_STREAM_SEEK_BEGIN, NULL);
118		✗	if (GATE_SUCCEEDED(result))
119			{
120		✗	result = gate_stream_read_block((gate_stream_t*)blockstream, out_buffer, sector_length, &length_returned);
121			}
122		✗	return result;
123			}
124
125		✗	gate_result_t gate_filesystem_read_fat_entries(gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t const* bootsect,
126			gate_uint16_t* fat_entries, gate_size_t fat_entries_capacity, gate_size_t* fat_entries_count)
127			{
128		✗	const unsigned fat_type = get_fat_type(bootsect);
129		✗	const unsigned fat_start = bootsect->bpb.reserved_sectors;
130		✗	const unsigned sector_len = bootsect->bpb.bytes_per_sector;
131			char local_buffer[512 * 3];
132		✗	char* buffer = &local_buffer[0];
133		✗	const gate_size_t buffer_required_len = (gate_size_t)sector_len * 3u;
134		✗	gate_size_t entry_counter = 0;
135		✗	gate_result_t ret = GATE_RESULT_FAILED;;
136
137
138		✗	if (sizeof(local_buffer) > buffer_required_len)
139			{
140		✗	buffer = gate_mem_alloc(buffer_required_len);
141		✗	if (buffer == NULL)
142			{
143		✗	return GATE_RESULT_OUTOFMEMORY;
144			}
145			}
146
147		✗	if (!fat_entries_count)
148			{
149		✗	fat_entries_count = &entry_counter;
150			}
151
152		✗	switch (fat_type)
153			{
154		✗	case 12:
155			{
156			unsigned ndx;
157		✗	for (ndx = 0; (ndx < bootsect->bpb.sectors_per_fat) && (fat_entries_capacity > 0); ndx += 3)
158			{
159			unsigned pos;
160		✗	ret = read_sector(blockstream, bootsect, fat_start + ndx, &buffer[0]);
161		✗	GATE_BREAK_IF_FAILED(ret);
162		✗	ret = read_sector(blockstream, bootsect, fat_start + ndx + 1, &buffer[sector_len]);
163		✗	GATE_BREAK_IF_FAILED(ret);
164		✗	ret = read_sector(blockstream, bootsect, fat_start + ndx + 2, &buffer[sector_len * 2]);
165		✗	GATE_BREAK_IF_FAILED(ret);
166
167		✗	for (pos = 0; (pos < 3 * sector_len) && (fat_entries_capacity > 0); pos += 3)
168			{
169		✗	*fat_entries = (gate_uint16_t)buffer[pos] | ((gate_uint16_t)buffer[pos + 1] << 8);
170		✗	++fat_entries;
171		✗	++(*fat_entries_count);
172		✗	if (0 == --fat_entries_capacity)
173			{
174		✗	break;
175			}
176
177		✗	*fat_entries = (((gate_uint16_t)buffer[pos + 1] >> 4) & 0x0f) | ((gate_uint16_t)buffer[pos + 2] << 4);
178		✗	++fat_entries;
179		✗	++(*fat_entries_count);
180		✗	--fat_entries_capacity;
181			}
182			}
183		✗	break;
184			}
185		✗	case 16:
186			case 32:
187			default:
188			{
189		✗	ret = GATE_RESULT_NOTSUPPORTED;
190		✗	break;
191			}
192			}
193
194		✗	if (buffer && (buffer != &local_buffer[0]))
195			{
196		✗	gate_mem_dealloc(buffer);
197			}
198		✗	return ret;
199			}
200
201		✗	gate_result_t gate_filesystem_read_next_fat_entry(
202			gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t const* bootsect, gate_uint32_t fat_entry, gate_uint32_t* next_fat_entry)
203			{
204		✗	const unsigned fat_type = get_fat_type(bootsect);
205		✗	const unsigned fat_start = bootsect->bpb.reserved_sectors;
206		✗	const unsigned sector_len = bootsect->bpb.bytes_per_sector;
207			unsigned char local_buffer[512 * 2];
208		✗	unsigned char* buffer = &local_buffer[0];
209		✗	const gate_size_t buffer_required_len = (gate_size_t)sector_len * 2u;
210		✗	gate_result_t ret = GATE_RESULT_FAILED;
211
212		✗	if (sizeof(local_buffer) > buffer_required_len)
213			{
214		✗	buffer = (unsigned char*)gate_mem_alloc(buffer_required_len);
215		✗	if (buffer == NULL)
216			{
217		✗	return GATE_RESULT_OUTOFMEMORY;
218			}
219			}
220
221		✗	switch (fat_type)
222			{
223		✗	case 12:
224			{
225			unsigned next_cluster;
226		✗	unsigned cluster_pos = fat_entry;
227		✗	unsigned fat_offset = (cluster_pos / 2) * 3;
228		✗	unsigned sector_num = fat_offset / sector_len;
229		✗	unsigned sector_offset = fat_offset % sector_len;
230
231		✗	ret = read_sector(blockstream, bootsect, fat_start + sector_num, (char*)&buffer[0]);
232		✗	GATE_BREAK_IF_FAILED(ret);
233		✗	if (sector_offset >= sector_len - 2)
234			{
235			/* fat entry is on the boundary to the next sector */
236		✗	ret = read_sector(blockstream, bootsect, fat_start + sector_num, (char*)&buffer[sector_len]);
237		✗	GATE_BREAK_IF_FAILED(ret);
238			}
239
240		✗	if ((cluster_pos & 1) == 0)
241			{
242		✗	next_cluster = (gate_uint16_t)buffer[sector_offset] | (((gate_uint16_t)buffer[sector_offset + 1] & 0x0f) << 8);
243			}
244			else
245			{
246		✗	next_cluster = (((gate_uint16_t)buffer[sector_offset + 1] >> 4) & 0x0f) | ((gate_uint16_t)buffer[sector_offset + 2] << 4);
247			}
248
249		✗	if (next_cluster >= 0xff8)
250			{
251		✗	ret = GATE_RESULT_ENDOFSTREAM;
252		✗	*next_fat_entry = 0;
253			}
254		✗	else if (next_cluster == 0xff7)
255			{
256		✗	ret = GATE_RESULT_INVALIDCONTENT;
257			}
258			else
259			{
260		✗	*next_fat_entry = next_cluster;
261		✗	ret = GATE_RESULT_OK;
262			}
263		✗	break;
264			}
265		✗	case 16:
266			case 32:
267			default:
268			{
269		✗	ret = GATE_RESULT_NOTSUPPORTED;
270		✗	break;
271			}
272			}
273
274		✗	if (buffer && (buffer != &local_buffer[0]))
275			{
276		✗	gate_mem_dealloc(buffer);
277			}
278		✗	return ret;
279			}
280
281
282
283		✗	gate_result_t gate_filesystem_read_fat_cluster(gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t const* bootsect,
284			gate_uint32_t cluster, char* buffer, gate_size_t buffer_capacity, gate_size_t* buffer_filled)
285			{
286		✗	unsigned fat_type = get_fat_type(bootsect);
287
288		✗	switch (fat_type)
289			{
290		✗	case 12:
291			{
292			unsigned total_clusters;
293			unsigned sector_num;
294			unsigned byte_count;
295			gate_int64_t stream_offset;
296			gate_result_t result;
297
298		✗	if (cluster < 2)
299			{
300			/* first FAT clusters has cluster-id 2 */
301		✗	return GATE_RESULT_INVALIDARG;
302			}
303		✗	cluster -= 2;
304		✗	total_clusters = get_total_data_clusters(bootsect);
305		✗	if (cluster >= total_clusters)
306			{
307		✗	return GATE_RESULT_OUTOFBOUNDS;
308			}
309		✗	sector_num = get_data_cluster_sector(bootsect, (unsigned)cluster);
310		✗	stream_offset = (gate_int64_t)sector_num * (gate_int64_t)bootsect->bpb.bytes_per_sector;
311		✗	byte_count = (unsigned)bootsect->bpb.sectors_per_cluster * (unsigned)bootsect->bpb.bytes_per_sector;
312		✗	if (buffer_capacity > byte_count)
313			{
314		✗	buffer_capacity = byte_count;
315			}
316		✗	result = gate_stream_seek(blockstream, stream_offset, GATE_STREAM_SEEK_BEGIN, NULL);
317		✗	GATE_RETURN_IF_FAILED(result);
318		✗	return gate_stream_read_block((gate_stream_t*)blockstream, buffer, buffer_capacity, buffer_filled);
319			}
320		✗	case 16:
321			case 32:
322			default:
323		✗	return GATE_RESULT_NOTSUPPORTED;
324			}
325			}
326
327		✗	static gate_result_t read_fat_dir(gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t const* bootsect,
328			unsigned start_sector, unsigned sectors_count, gate_filesystem_fat_direntry_callback_t callback, void* user_param)
329			{
330		✗	const unsigned sectorlen = bootsect->bpb.bytes_per_sector;
331		✗	const unsigned sectorentries = sectorlen / 32;
332
333		✗	gate_result_t result = GATE_RESULT_OK;
334			unsigned ndx;
335
336		✗	for (ndx = 0; ndx != sectors_count; ++ndx)
337			{
338			gate_filesystem_fat_direntry_t const* ptr_direntry;
339			unsigned ent;
340			char buffer[4096];
341		✗	result = read_sector(blockstream, bootsect, start_sector + ndx, buffer);
342		✗	GATE_RETURN_IF_FAILED(result);
343		✗	ptr_direntry = (gate_filesystem_fat_direntry_t const*)buffer;
344
345		✗	for (ent = 0; ent != sectorentries; ++ent, ++ptr_direntry)
346			{
347		✗	switch ((unsigned char)ptr_direntry->filename[0])
348			{
349		✗	case 0:
350			/* end of directory reached */
351		✗	return GATE_RESULT_OK;
352		✗	case 0xe5:
353			/* unused_entry, skip */
354		✗	continue;
355		✗	default:
356		✗	if (ptr_direntry->attributes == 0x0f)
357			{
358			/* long filename, skip */
359		✗	continue;
360			}
361
362			/* standard entry: */
363		✗	if (!callback(ptr_direntry, user_param))
364			{
365			/* canceled by callback */
366		✗	return GATE_RESULT_CANCELED;
367			}
368		✗	break;
369			}
370			}
371			}
372		✗	return result;
373			}
374
375		✗	gate_result_t gate_filesystem_read_fat_directory(gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t const* bootsect,
376			gate_string_t const* subdir, gate_filesystem_fat_direntry_callback_t callback, void* user_param)
377			{
378		✗	const unsigned root_sector = get_first_root_dir_sector(bootsect);
379		✗	const unsigned root_sectors_count = get_root_dir_sectors(bootsect);
380
381		✗	gate_result_t ret = read_fat_dir(blockstream, bootsect, root_sector, root_sectors_count, callback, user_param);
382		✗	if (ret == GATE_RESULT_CANCELED)
383			{
384		✗	ret = GATE_RESULT_OK;
385			}
386		✗	return ret;
387			}
388
389			struct find_fat_file_param
390			{
391			char filename[8];
392			char fileext[3];
393			gate_filesystem_fat_direntry_t matched_entry;
394			};
395
396		✗	static gate_bool_t GATE_CALL find_fat_file_cb(gate_filesystem_fat_direntry_t const* entry, void* user_param)
397			{
398		✗	struct find_fat_file_param* param = (struct find_fat_file_param*)user_param;
399		✗	if ((0 == gate_mem_compare(entry->filename, param->filename, 8))
400		✗	&& (0 == gate_mem_compare(entry->extension, param->fileext, 3)))
401			{
402		✗	gate_mem_copy(&param->matched_entry, entry, sizeof(gate_filesystem_fat_direntry_t));
403		✗	return false;
404			}
405		✗	return true;
406			}
407
408
409		✗	gate_result_t gate_filesystem_find_fat_file(gate_controlstream_t* blockstream, gate_filesystem_fat_bootsect_t const* bootsect,
410			gate_string_t const* path, gate_filesystem_fat_direntry_t* ptr_found_entry)
411			{
412			gate_result_t ret;
413			gate_size_t pos;
414		✗	gate_size_t len = gate_string_length(path);
415			struct find_fat_file_param param;
416
417		✗	gate_mem_clear(&param, sizeof(param));
418		✗	gate_mem_fill(&param.filename[0], ' ', sizeof(param.filename));
419		✗	gate_mem_fill(&param.fileext[0], ' ', sizeof(param.fileext));
420		✗	pos = gate_string_char_pos_last(path, '.');
421		✗	if (pos == GATE_STR_NPOS)
422			{
423		✗	pos = len > 8 ? 8 : len;
424		✗	gate_mem_copy(param.filename, gate_string_ptr(path, 0), pos);
425			}
426			else
427			{
428		✗	gate_mem_copy(param.filename, gate_string_ptr(path, 0), pos > 8 ? 8 : pos);
429		✗	if (len - pos - 1 >= 3)
430			{
431		✗	gate_mem_copy(param.fileext, gate_string_ptr(path, pos + 1), 3);
432			}
433			else
434			{
435		✗	gate_mem_copy(param.fileext, gate_string_ptr(path, pos + 1), len - pos - 1);
436			}
437			}
438
439		✗	ret = gate_filesystem_read_fat_directory(blockstream, bootsect, NULL, &find_fat_file_cb, &param);
440		✗	if (GATE_SUCCEEDED(ret))
441			{
442		✗	if (param.matched_entry.filename[0] != 0)
443			{
444		✗	gate_mem_copy(ptr_found_entry, &param.matched_entry, sizeof(gate_filesystem_fat_direntry_t));
445			}
446			else
447			{
448		✗	ret = GATE_RESULT_NOMATCH;
449			}
450			}
451		✗	return ret;
452			}
453