Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	fx_file_extended_truncate.c	Lines:	63	63	100.0 %
Date:	2024-03-11 05:15:45	Branches:	28	28	100.0 %


/***************************************************************************
 * Copyright (c) 2024 Microsoft Corporation
 *
 * This program and the accompanying materials are made available under the
 * terms of the MIT License which is available at
 * https://opensource.org/licenses/MIT.
 *
 * SPDX-License-Identifier: MIT
 **************************************************************************/


/**************************************************************************/
/**************************************************************************/
/**                                                                       */
/** FileX Component                                                       */
/**                                                                       */
/**   File                                                                */
/**                                                                       */
/**************************************************************************/
/**************************************************************************/

#define FX_SOURCE_CODE


/* Include necessary system files.  */

#include "fx_api.h"
#include "fx_system.h"
#include "fx_directory.h"
#include "fx_file.h"
#include "fx_utility.h"
#ifdef FX_ENABLE_FAULT_TOLERANT
#include "fx_fault_tolerant.h"
#endif /* FX_ENABLE_FAULT_TOLERANT */


/**************************************************************************/
/*                                                                        */
/*  FUNCTION                                               RELEASE        */
/*                                                                        */
/*    _fx_file_extended_truncate                          PORTABLE C      */
/*                                                           6.1          */
/*  AUTHOR                                                                */
/*                                                                        */
/*    William E. Lamie, Microsoft Corporation                             */
/*                                                                        */
/*  DESCRIPTION                                                           */
/*                                                                        */
/*    This function sets the file to the specified size, if smaller than  */
/*    the current file size.  If the new file size is less than the       */
/*    current file read/write position, the internal file pointers will   */
/*    also be modified.                                                   */
/*                                                                        */
/*  INPUT                                                                 */
/*                                                                        */
/*    file_ptr                              File control block pointer    */
/*    size                                  New size of the file in bytes */
/*                                                                        */
/*  OUTPUT                                                                */
/*                                                                        */
/*    return status                                                       */
/*                                                                        */
/*  CALLS                                                                 */
/*                                                                        */
/*    _fx_utility_FAT_entry_read            Read a FAT entry              */
/*    _fx_fault_tolerant_transaction_start  Start fault tolerant          */
/*                                            transaction                 */
/*    _fx_fault_tolerant_transaction_end    End fault tolerant transaction*/
/*    _fx_fault_tolerant_recover            Recover FAT chain             */
/*    _fx_fault_tolerant_reset_log_file     Reset the log file            */
/*                                                                        */
/*  CALLED BY                                                             */
/*                                                                        */
/*    Application Code                                                    */
/*                                                                        */
/*  RELEASE HISTORY                                                       */
/*                                                                        */
/*    DATE              NAME                      DESCRIPTION             */
/*                                                                        */
/*  05-19-2020     William E. Lamie         Initial Version 6.0           */
/*  09-30-2020     William E. Lamie         Modified comment(s),          */
/*                                            resulting in version 6.1    */
/*                                                                        */
/**************************************************************************/
UINT  _fx_file_extended_truncate(FX_FILE *file_ptr, ULONG64 size)
{

UINT                   status;
ULONG                  cluster;
ULONG                  contents = 0;
ULONG                  bytes_per_cluster;
ULONG                  last_cluster;
ULONG                  cluster_count;
ULONG64                bytes_remaining;
FX_MEDIA              *media_ptr;

#ifndef FX_DONT_UPDATE_OPEN_FILES
ULONG                  open_count;
FX_FILE               *search_ptr;
#endif

#ifdef TX_ENABLE_EVENT_TRACE
TX_TRACE_BUFFER_ENTRY *trace_event;
ULONG                  trace_timestamp;
#endif


    /* First, determine if the file is still open.  */
    if (file_ptr -> fx_file_id != FX_FILE_ID)
    {

        /* Return the file not open error status.  */
        return(FX_NOT_OPEN);
    }

#ifndef FX_MEDIA_STATISTICS_DISABLE
    /* Setup pointer to media structure.  */
    media_ptr =  file_ptr -> fx_file_media_ptr;

    /* Increment the number of times this service has been called.  */
    media_ptr -> fx_media_file_truncates++;
#endif

    /* Setup pointer to associated media control block.  */
    media_ptr =  file_ptr -> fx_file_media_ptr;

    /* If trace is enabled, insert this event into the trace buffer.  */
    FX_TRACE_IN_LINE_INSERT(FX_TRACE_FILE_TRUNCATE, file_ptr, size, file_ptr -> fx_file_current_file_size, 0, FX_TRACE_FILE_EVENTS, &trace_event, &trace_timestamp)

    /* Protect against other threads accessing the media.  */
    FX_PROTECT

    /* Make sure this file is open for writing.  */
    if (file_ptr -> fx_file_open_mode != FX_OPEN_FOR_WRITE)
    {

        /* Release media protection.  */
        FX_UNPROTECT

        /* Return the access error exception - a write was attempted from
           a file opened for reading!  */
        return(FX_ACCESS_ERROR);
    }

    /* Check for write protect at the media level (set by driver).  */
    if (media_ptr -> fx_media_driver_write_protect)
    {

        /* Release media protection.  */
        FX_UNPROTECT

        /* Return write protect error.  */
        return(FX_WRITE_PROTECT);
    }

    /* Setup the new file size - if less than the current size.  */
    if (size < file_ptr -> fx_file_current_file_size)
    {

        /* Setup the new size.  */
        file_ptr -> fx_file_current_file_size =  size;

        /* Set the modified flag as well.  */
        file_ptr -> fx_file_modified =  FX_TRUE;

        /* Update the trace event with the truncated size.  */
        FX_TRACE_EVENT_UPDATE(trace_event, trace_timestamp, FX_TRACE_FILE_TRUNCATE, 0, 0, 0, size)
    }
    else
    {

        /* Update the trace event with the truncated size.  */
        FX_TRACE_EVENT_UPDATE(trace_event, trace_timestamp, FX_TRACE_FILE_TRUNCATE, 0, 0, 0, file_ptr -> fx_file_current_file_size)

        /* Release media protection.  */
        FX_UNPROTECT

        /* Just return, the new size is larger than the current size.  */
        return(FX_SUCCESS);
    }

#ifndef FX_DONT_UPDATE_OPEN_FILES

    /* Search the opened files list to see if the same file is opened for reading.  */
    open_count =  media_ptr -> fx_media_opened_file_count;
    search_ptr =  media_ptr -> fx_media_opened_file_list;
    while (open_count)
    {

        /* Is this file the same file opened for reading?  */
        if ((search_ptr != file_ptr) &&
            (search_ptr -> fx_file_dir_entry.fx_dir_entry_log_sector ==
             file_ptr -> fx_file_dir_entry.fx_dir_entry_log_sector) &&
            (search_ptr -> fx_file_dir_entry.fx_dir_entry_byte_offset ==
             file_ptr -> fx_file_dir_entry.fx_dir_entry_byte_offset))
        {

            /* Yes, the same file is opened for reading.  */

            /* Setup the new file size.  */
            search_ptr -> fx_file_current_file_size =  size;
            search_ptr -> fx_file_dir_entry.fx_dir_entry_file_size = size;
        }

        /* Adjust the pointer and decrement the search count.  */
        search_ptr =  search_ptr -> fx_file_opened_next;
        open_count--;
    }
#endif

    /* Now check to see if the read/write internal file pointers need
       to be adjusted.  */
    if (file_ptr -> fx_file_current_file_offset > file_ptr -> fx_file_current_file_size)
    {

        /* Calculate the number of bytes per cluster.  */
        bytes_per_cluster =  ((ULONG)media_ptr -> fx_media_bytes_per_sector) *
            ((ULONG)media_ptr -> fx_media_sectors_per_cluster);

        /* At this point, we are ready to walk list of clusters to setup the
           seek position of this file.  */
        cluster =           file_ptr -> fx_file_first_physical_cluster;
        bytes_remaining =   size;
        last_cluster =      0;
        cluster_count =     0;

        /* Follow the link of FAT entries.  */
        while ((cluster >= FX_FAT_ENTRY_START) && (cluster < media_ptr -> fx_media_fat_reserved))
        {

            /* Increment the number of clusters.  */
            cluster_count++;

            /* Read the current cluster entry from the FAT.  */
            status =  _fx_utility_FAT_entry_read(media_ptr, cluster, &contents);

            /* Check the return value.  */
            if (status != FX_SUCCESS)
            {

                /* Release media protection.  */
                FX_UNPROTECT

                /* Return the error status.  */
                return(status);
            }

            /* Save the last valid cluster.  */
            last_cluster =  cluster;

            /* Setup for the next cluster.  */
            cluster =  contents;

            /* Determine if this is the last written cluster.  */
            if (bytes_remaining >= bytes_per_cluster)
            {

                /* Still more seeking, just decrement the working byte offset.  */
                bytes_remaining =  bytes_remaining - bytes_per_cluster;
            }
            else
            {

                /* This is the cluster that contains the seek position.  */
                break;
            }
        }

        /* Check for errors in traversal of the FAT chain.  */
        if (size > (((ULONG64) bytes_per_cluster) * ((ULONG64) cluster_count)))
        {

            /* Release media protection.  */
            FX_UNPROTECT

            /* This is an error that suggests a corrupt file.  */
            return(FX_FILE_CORRUPT);
        }

        /* Position the pointers to the new offset.  */
        file_ptr -> fx_file_current_physical_cluster =  last_cluster;
        file_ptr -> fx_file_current_relative_cluster =  cluster_count - 1;
        file_ptr -> fx_file_current_logical_sector =    ((ULONG)media_ptr -> fx_media_data_sector_start) +
            (((ULONG64)file_ptr -> fx_file_current_physical_cluster - FX_FAT_ENTRY_START) *
             ((ULONG)media_ptr -> fx_media_sectors_per_cluster)) +
            (bytes_remaining / (ULONG)media_ptr -> fx_media_bytes_per_sector);
        file_ptr -> fx_file_current_relative_sector =   (UINT)((bytes_remaining / (ULONG)media_ptr -> fx_media_bytes_per_sector));
        file_ptr -> fx_file_current_file_offset =       size;
        file_ptr -> fx_file_current_logical_offset =    (ULONG)bytes_remaining % ((ULONG)media_ptr -> fx_media_bytes_per_sector);
    }

#ifdef FX_ENABLE_FAULT_TOLERANT
    if (media_ptr -> fx_media_fault_tolerant_enabled)
    {

        /* Start transaction. */
        _fx_fault_tolerant_transaction_start(media_ptr);

        /* Copy the new file size into the directory entry.  */
        file_ptr -> fx_file_dir_entry.fx_dir_entry_file_size = file_ptr -> fx_file_current_file_size;

        /* Write the directory entry to the media.  */
        status =  _fx_directory_entry_write(media_ptr, &(file_ptr -> fx_file_dir_entry));

        /* Check for a good status.  */
        if (status != FX_SUCCESS)
        {

            FX_FAULT_TOLERANT_TRANSACTION_FAIL(media_ptr);

            /* Release media protection.  */
            FX_UNPROTECT

            /* Error writing the directory.  */
            return(status);
        }

        /* End transaction. */
        status = _fx_fault_tolerant_transaction_end(media_ptr);

        /* Check for a good status.  */
        if (status != FX_SUCCESS)
        {

            /* Release media protection.  */
            FX_UNPROTECT

            /* Error writing the directory.  */
            return(status);
        }

        /* Update maximum size used if necessary. */
        if (size < file_ptr -> fx_file_maximum_size_used)
        {
            file_ptr -> fx_file_maximum_size_used = size;
        }
    }
#endif /* FX_ENABLE_FAULT_TOLERANT */

    /* Release media protection.  */
    FX_UNPROTECT

    /* Truncate is complete, return successful status.  */
    return(FX_SUCCESS);
}



Generated by: GCOVR (Version 4.1)

Line	Branch	Exec	Source
1			/***************************************************************************
2			* Copyright (c) 2024 Microsoft Corporation
3			*
4			* This program and the accompanying materials are made available under the
5			* terms of the MIT License which is available at
6			* https://opensource.org/licenses/MIT.
7			*
8			* SPDX-License-Identifier: MIT
9			**************************************************************************/
10
11
12			/**************************************************************************/
13			/**************************************************************************/
14			/** */
15			/** FileX Component */
16			/** */
17			/** File */
18			/** */
19			/**************************************************************************/
20			/**************************************************************************/
21
22			#define FX_SOURCE_CODE
23
24
25			/* Include necessary system files. */
26
27			#include "fx_api.h"
28			#include "fx_system.h"
29			#include "fx_directory.h"
30			#include "fx_file.h"
31			#include "fx_utility.h"
32			#ifdef FX_ENABLE_FAULT_TOLERANT
33			#include "fx_fault_tolerant.h"
34			#endif /* FX_ENABLE_FAULT_TOLERANT */
35
36
37			/**************************************************************************/
38			/* */
39			/* FUNCTION RELEASE */
40			/* */
41			/* _fx_file_extended_truncate PORTABLE C */
42			/* 6.1 */
43			/* AUTHOR */
44			/* */
45			/* William E. Lamie, Microsoft Corporation */
46			/* */
47			/* DESCRIPTION */
48			/* */
49			/* This function sets the file to the specified size, if smaller than */
50			/* the current file size. If the new file size is less than the */
51			/* current file read/write position, the internal file pointers will */
52			/* also be modified. */
53			/* */
54			/* INPUT */
55			/* */
56			/* file_ptr File control block pointer */
57			/* size New size of the file in bytes */
58			/* */
59			/* OUTPUT */
60			/* */
61			/* return status */
62			/* */
63			/* CALLS */
64			/* */
65			/* _fx_utility_FAT_entry_read Read a FAT entry */
66			/* _fx_fault_tolerant_transaction_start Start fault tolerant */
67			/* transaction */
68			/* _fx_fault_tolerant_transaction_end End fault tolerant transaction*/
69			/* _fx_fault_tolerant_recover Recover FAT chain */
70			/* _fx_fault_tolerant_reset_log_file Reset the log file */
71			/* */
72			/* CALLED BY */
73			/* */
74			/* Application Code */
75			/* */
76			/* RELEASE HISTORY */
77			/* */
78			/* DATE NAME DESCRIPTION */
79			/* */
80			/* 05-19-2020 William E. Lamie Initial Version 6.0 */
81			/* 09-30-2020 William E. Lamie Modified comment(s), */
82			/* resulting in version 6.1 */
83			/* */
84			/**************************************************************************/
85		11	UINT _fx_file_extended_truncate(FX_FILE *file_ptr, ULONG64 size)
86			{
87
88			UINT status;
89			ULONG cluster;
90		11	ULONG contents = 0;
91			ULONG bytes_per_cluster;
92			ULONG last_cluster;
93			ULONG cluster_count;
94			ULONG64 bytes_remaining;
95			FX_MEDIA *media_ptr;
96
97			#ifndef FX_DONT_UPDATE_OPEN_FILES
98			ULONG open_count;
99			FX_FILE *search_ptr;
100			#endif
101
102			#ifdef TX_ENABLE_EVENT_TRACE
103			TX_TRACE_BUFFER_ENTRY *trace_event;
104			ULONG trace_timestamp;
105			#endif
106
107
108			/* First, determine if the file is still open. */
109	✓✓	11	if (file_ptr -> fx_file_id != FX_FILE_ID)
110			{
111
112			/* Return the file not open error status. */
113		1	return(FX_NOT_OPEN);
114			}
115
116			#ifndef FX_MEDIA_STATISTICS_DISABLE
117			/* Setup pointer to media structure. */
118		10	media_ptr = file_ptr -> fx_file_media_ptr;
119
120			/* Increment the number of times this service has been called. */
121		10	media_ptr -> fx_media_file_truncates++;
122			#endif
123
124			/* Setup pointer to associated media control block. */
125		10	media_ptr = file_ptr -> fx_file_media_ptr;
126
127			/* If trace is enabled, insert this event into the trace buffer. */
128			FX_TRACE_IN_LINE_INSERT(FX_TRACE_FILE_TRUNCATE, file_ptr, size, file_ptr -> fx_file_current_file_size, 0, FX_TRACE_FILE_EVENTS, &trace_event, &trace_timestamp)
129
130			/* Protect against other threads accessing the media. */
131		10	FX_PROTECT
132
133			/* Make sure this file is open for writing. */
134	✓✓	10	if (file_ptr -> fx_file_open_mode != FX_OPEN_FOR_WRITE)
135			{
136
137			/* Release media protection. */
138		1	FX_UNPROTECT
139
140			/* Return the access error exception - a write was attempted from
141			a file opened for reading! */
142		1	return(FX_ACCESS_ERROR);
143			}
144
145			/* Check for write protect at the media level (set by driver). */
146	✓✓	9	if (media_ptr -> fx_media_driver_write_protect)
147			{
148
149			/* Release media protection. */
150		1	FX_UNPROTECT
151
152			/* Return write protect error. */
153		1	return(FX_WRITE_PROTECT);
154			}
155
156			/* Setup the new file size - if less than the current size. */
157	✓✓	8	if (size < file_ptr -> fx_file_current_file_size)
158			{
159
160			/* Setup the new size. */
161		7	file_ptr -> fx_file_current_file_size = size;
162
163			/* Set the modified flag as well. */
164		7	file_ptr -> fx_file_modified = FX_TRUE;
165
166			/* Update the trace event with the truncated size. */
167			FX_TRACE_EVENT_UPDATE(trace_event, trace_timestamp, FX_TRACE_FILE_TRUNCATE, 0, 0, 0, size)
168			}
169			else
170			{
171
172			/* Update the trace event with the truncated size. */
173			FX_TRACE_EVENT_UPDATE(trace_event, trace_timestamp, FX_TRACE_FILE_TRUNCATE, 0, 0, 0, file_ptr -> fx_file_current_file_size)
174
175			/* Release media protection. */
176		1	FX_UNPROTECT
177
178			/* Just return, the new size is larger than the current size. */
179		1	return(FX_SUCCESS);
180			}
181
182			#ifndef FX_DONT_UPDATE_OPEN_FILES
183
184			/* Search the opened files list to see if the same file is opened for reading. */
185		7	open_count = media_ptr -> fx_media_opened_file_count;
186		7	search_ptr = media_ptr -> fx_media_opened_file_list;
187	✓✓	31	while (open_count)
188			{
189
190			/* Is this file the same file opened for reading? */
191	✓✓	24	if ((search_ptr != file_ptr) &&
192		17	(search_ptr -> fx_file_dir_entry.fx_dir_entry_log_sector ==
193	✓✓	17	file_ptr -> fx_file_dir_entry.fx_dir_entry_log_sector) &&
194		12	(search_ptr -> fx_file_dir_entry.fx_dir_entry_byte_offset ==
195	✓✓	12	file_ptr -> fx_file_dir_entry.fx_dir_entry_byte_offset))
196			{
197
198			/* Yes, the same file is opened for reading. */
199
200			/* Setup the new file size. */
201		5	search_ptr -> fx_file_current_file_size = size;
202		5	search_ptr -> fx_file_dir_entry.fx_dir_entry_file_size = size;
203			}
204
205			/* Adjust the pointer and decrement the search count. */
206		24	search_ptr = search_ptr -> fx_file_opened_next;
207		24	open_count--;
208			}
209			#endif
210
211			/* Now check to see if the read/write internal file pointers need
212			to be adjusted. */
213	✓✓	7	if (file_ptr -> fx_file_current_file_offset > file_ptr -> fx_file_current_file_size)
214			{
215
216			/* Calculate the number of bytes per cluster. */
217		6	bytes_per_cluster = ((ULONG)media_ptr -> fx_media_bytes_per_sector) *
218		6	((ULONG)media_ptr -> fx_media_sectors_per_cluster);
219
220			/* At this point, we are ready to walk list of clusters to setup the
221			seek position of this file. */
222		6	cluster = file_ptr -> fx_file_first_physical_cluster;
223		6	bytes_remaining = size;
224		6	last_cluster = 0;
225		6	cluster_count = 0;
226
227			/* Follow the link of FAT entries. */
228	✓✓✓✓	270	while ((cluster >= FX_FAT_ENTRY_START) && (cluster < media_ptr -> fx_media_fat_reserved))
229			{
230
231			/* Increment the number of clusters. */
232		268	cluster_count++;
233
234			/* Read the current cluster entry from the FAT. */
235		268	status = _fx_utility_FAT_entry_read(media_ptr, cluster, &contents);
236
237			/* Check the return value. */
238	✓✓	268	if (status != FX_SUCCESS)
239			{
240
241			/* Release media protection. */
242		1	FX_UNPROTECT
243
244			/* Return the error status. */
245		1	return(status);
246			}
247
248			/* Save the last valid cluster. */
249		267	last_cluster = cluster;
250
251			/* Setup for the next cluster. */
252		267	cluster = contents;
253
254			/* Determine if this is the last written cluster. */
255	✓✓	267	if (bytes_remaining >= bytes_per_cluster)
256			{
257
258			/* Still more seeking, just decrement the working byte offset. */
259		264	bytes_remaining = bytes_remaining - bytes_per_cluster;
260			}
261			else
262			{
263
264			/* This is the cluster that contains the seek position. */
265		3	break;
266			}
267			}
268
269			/* Check for errors in traversal of the FAT chain. */
270	✓✓	5	if (size > (((ULONG64) bytes_per_cluster) * ((ULONG64) cluster_count)))
271			{
272
273			/* Release media protection. */
274		2	FX_UNPROTECT
275
276			/* This is an error that suggests a corrupt file. */
277		2	return(FX_FILE_CORRUPT);
278			}
279
280			/* Position the pointers to the new offset. */
281		3	file_ptr -> fx_file_current_physical_cluster = last_cluster;
282		3	file_ptr -> fx_file_current_relative_cluster = cluster_count - 1;
283		3	file_ptr -> fx_file_current_logical_sector = ((ULONG)media_ptr -> fx_media_data_sector_start) +
284		3	(((ULONG64)file_ptr -> fx_file_current_physical_cluster - FX_FAT_ENTRY_START) *
285		3	((ULONG)media_ptr -> fx_media_sectors_per_cluster)) +
286		3	(bytes_remaining / (ULONG)media_ptr -> fx_media_bytes_per_sector);
287		3	file_ptr -> fx_file_current_relative_sector = (UINT)((bytes_remaining / (ULONG)media_ptr -> fx_media_bytes_per_sector));
288		3	file_ptr -> fx_file_current_file_offset = size;
289		3	file_ptr -> fx_file_current_logical_offset = (ULONG)bytes_remaining % ((ULONG)media_ptr -> fx_media_bytes_per_sector);
290			}
291
292			#ifdef FX_ENABLE_FAULT_TOLERANT
293			if (media_ptr -> fx_media_fault_tolerant_enabled)
294			{
295
296			/* Start transaction. */
297			_fx_fault_tolerant_transaction_start(media_ptr);
298
299			/* Copy the new file size into the directory entry. */
300			file_ptr -> fx_file_dir_entry.fx_dir_entry_file_size = file_ptr -> fx_file_current_file_size;
301
302			/* Write the directory entry to the media. */
303			status = _fx_directory_entry_write(media_ptr, &(file_ptr -> fx_file_dir_entry));
304
305			/* Check for a good status. */
306			if (status != FX_SUCCESS)
307			{
308
309			FX_FAULT_TOLERANT_TRANSACTION_FAIL(media_ptr);
310
311			/* Release media protection. */
312			FX_UNPROTECT
313
314			/* Error writing the directory. */
315			return(status);
316			}
317
318			/* End transaction. */
319			status = _fx_fault_tolerant_transaction_end(media_ptr);
320
321			/* Check for a good status. */
322			if (status != FX_SUCCESS)
323			{
324
325			/* Release media protection. */
326			FX_UNPROTECT
327
328			/* Error writing the directory. */
329			return(status);
330			}
331
332			/* Update maximum size used if necessary. */
333			if (size < file_ptr -> fx_file_maximum_size_used)
334			{
335			file_ptr -> fx_file_maximum_size_used = size;
336			}
337			}
338			#endif /* FX_ENABLE_FAULT_TOLERANT */
339
340			/* Release media protection. */
341		4	FX_UNPROTECT
342
343			/* Truncate is complete, return successful status. */
344		4	return(FX_SUCCESS);
345			}
346