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/**************************************************************************/
/* */
/* Copyright (c) Microsoft Corporation. All rights reserved. */
/* */
/* This software is licensed under the Microsoft Software License */
/* Terms for Microsoft Azure RTOS. Full text of the license can be */
/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
/* and in the root directory of this software. */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** FileX Component */
/** */
/** Media */
/** */
/**************************************************************************/
/**************************************************************************/
#define FX_SOURCE_CODE
/* Include necessary system files. */
#include "fx_api.h"
#include "fx_system.h"
#include "fx_directory.h"
#include "fx_media.h"
#include "fx_utility.h"
#ifdef FX_ENABLE_EXFAT
#include "fx_directory_exFAT.h"
#endif /* FX_ENABLE_EXFAT */
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _fx_media_volume_get_extended PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function reads the volume name stored in the media's boot */
/* record or root directory. */
/* */
/* INPUT */
/* */
/* media_ptr Media control block pointer */
/* volume_name Pointer to destination for */
/* the volume name (maximum */
/* 11 characters + NULL) */
/* volume_name_buffer_length Buffer length for volume_name */
/* volume_source Source of volume */
/* */
/* OUTPUT */
/* */
/* return status */
/* */
/* CALLS */
/* */
/* _fx_utility_logical_sector_read Read directory sector */
/* _fx_directory_entry_read Directory entry read */
/* */
/* 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_media_volume_get_extended(FX_MEDIA *media_ptr, CHAR *volume_name, UINT volume_name_buffer_length, UINT volume_source)
{
UINT status, offset;
ULONG i;
INT j;
#ifdef FX_ENABLE_EXFAT
ULONG character_count;
#endif /* FX_ENABLE_EXFAT */
FX_DIR_ENTRY dir_entry;
/* Clear the volume name. */
volume_name[0] = FX_NULL;
/* Check the media to make sure it is open. */
if (media_ptr -> fx_media_id != FX_MEDIA_ID)
{
/* Return the media not opened error. */
return(FX_MEDIA_NOT_OPEN);
}
/* If trace is enabled, insert this event into the trace buffer. */
FX_TRACE_IN_LINE_INSERT(FX_TRACE_MEDIA_VOLUME_GET, media_ptr, volume_name, volume_source, 0, FX_TRACE_MEDIA_EVENTS, 0, 0)
/* Protect against other threads accessing the media. */
FX_PROTECT
#ifdef FX_ENABLE_EXFAT
if (media_ptr -> fx_media_FAT_type == FX_exFAT)
{
volume_source = FX_DIRECTORY_SECTOR;
}
#endif /* FX_ENABLE_EXFAT */
/* Ensure the volume name is NULL initially. */
volume_name[0] = FX_NULL;
if (volume_source == FX_DIRECTORY_SECTOR)
{
/* Setup pointer to media name buffer. */
dir_entry.fx_dir_entry_name = media_ptr -> fx_media_name_buffer;
/* Clear the short name string. */
dir_entry.fx_dir_entry_short_name[0] = 0;
/* Attempt to find the volume name in the root directory. */
i = 0;
do
{
/* Read an entry from the root directory. */
status = _fx_directory_entry_read(media_ptr, FX_NULL, &i, &dir_entry);
/* Check for error status. */
if (status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Return to caller. */
return(status);
}
/* Check for a volume name. */
#ifdef FX_ENABLE_EXFAT
if (dir_entry.fx_dir_entry_attributes & FX_VOLUME || dir_entry.fx_dir_entry_type == FX_EXFAT_DIR_ENTRY_TYPE_VOLUME_LABEL)
#else
if (dir_entry.fx_dir_entry_attributes & FX_VOLUME)
#endif /* FX_ENABLE_EXFAT */
{
/* Yes, we have found a previously set volume name. */
break;
}
/* Move to next directory entry. */
i++;
} while (i < media_ptr -> fx_media_root_directory_entries);
/* Determine if a volume entry has been found. */
if (i < media_ptr -> fx_media_root_directory_entries)
{
/* Read the logical directory sector. */
status = _fx_utility_logical_sector_read(media_ptr, (ULONG64) dir_entry.fx_dir_entry_log_sector,
media_ptr -> fx_media_memory_buffer, ((ULONG) 1), FX_DIRECTORY_SECTOR);
/* Determine if an error occurred. */
if (status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Return error code. */
return(status);
}
/* Offset to volume label entry. */
offset = dir_entry.fx_dir_entry_byte_offset;
#ifdef FX_ENABLE_EXFAT
if (media_ptr -> fx_media_FAT_type == FX_exFAT)
{
/* Read character count of volume label. */
character_count = media_ptr -> fx_media_memory_buffer[offset + FX_EXFAT_CHAR_COUNT];
/* Check if the buffer is too short for the name. */
if (character_count >= volume_name_buffer_length)
{
/* Buffer too short, return error. */
status = FX_BUFFER_ERROR;
/* Set character count to fit for the buffer. */
character_count = volume_name_buffer_length - 1;
}
/* Move to volume label field. */
offset += FX_EXFAT_VOLUME_LABEL;
for (i = 0; i < character_count; i++)
{
/* Read one character of volume label. */
volume_name[i] = (CHAR)_fx_utility_16_unsigned_read(&media_ptr -> fx_media_memory_buffer[offset]);
/* Move to next character. */
offset += 2;
}
/* NULL terminate the volume name. */
volume_name[i] = FX_NULL;
}
else
{
#endif /* FX_ENABLE_EXFAT */
/* Skip trailing space characters of volume name. */
for (j = 10; j >= 0; j--)
{
/* Check for space character. */
if (media_ptr -> fx_media_memory_buffer[offset + (UINT)j] != (UCHAR)' ')
{
/* Last character found. */
break;
}
}
/* Check if the buffer is too short for the name. */
if (j >= (INT)volume_name_buffer_length - 1)
{
/* Buffer too short, return error. */
status = FX_BUFFER_ERROR;
/* Set character count to fit for the buffer. */
j = (INT)volume_name_buffer_length - 2;
}
/* NULL terminate the volume name. */
volume_name[j + 1] = FX_NULL;
/* Pickup the remaining characters of the volume name from the boot sector. */
for (; j >= 0; j--)
{
/* Pickup byte of volume name. */
volume_name[j] = (CHAR)media_ptr -> fx_media_memory_buffer[offset + (UINT)j];
}
#ifdef FX_ENABLE_EXFAT
}
#endif /* FX_ENABLE_EXFAT */
/* Release media protection. */
FX_UNPROTECT
/* Return the completion status. */
return(status);
}
}
/* Read volume name from boot record. */
/* Read the logical directory sector 0 - we just do this to get a memory_buffer pointer */
status = _fx_utility_logical_sector_read(media_ptr, ((ULONG64) 0),
media_ptr -> fx_media_memory_buffer, ((ULONG) 1), FX_DATA_SECTOR);
/* Check the return status. */
if (status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Return the error status. */
return(status);
}
#ifndef FX_MEDIA_STATISTICS_DISABLE
/* Increment the number of driver read boot sector requests. */
media_ptr -> fx_media_driver_boot_read_requests++;
#endif
/* Build the driver request to read the boot record. */
media_ptr -> fx_media_driver_request = FX_DRIVER_BOOT_READ;
media_ptr -> fx_media_driver_status = FX_IO_ERROR;
media_ptr -> fx_media_driver_buffer = media_ptr -> fx_media_memory_buffer;
media_ptr -> fx_media_driver_sectors = 1;
media_ptr -> fx_media_driver_sector_type = FX_BOOT_SECTOR;
/* If trace is enabled, insert this event into the trace buffer. */
FX_TRACE_IN_LINE_INSERT(FX_TRACE_INTERNAL_IO_DRIVER_BOOT_READ, media_ptr, media_ptr -> fx_media_memory_buffer, 0, 0, FX_TRACE_INTERNAL_EVENTS, 0, 0)
/* Invoke the driver to read the boot sector. */
(media_ptr -> fx_media_driver_entry) (media_ptr);
/* Determine if the request is successful. */
if (media_ptr -> fx_media_driver_status)
{
/* Release media protection. */
FX_UNPROTECT
/* An error occurred in the driver. */
return(media_ptr -> fx_media_driver_status);
}
/* Calculate the offset to the volume name based on the type of FAT. */
if (media_ptr -> fx_media_32_bit_FAT)
{
/* FAT32 offset to volume name. */
offset = FX_VOLUME_LABEL_32;
}
else
{
/* FAT12/16 offset to volume name. */
offset = FX_VOLUME_LABEL;
}
/* Skip trailing space characters of volume name. */
for (j = 10; j >= 0; j--)
{
/* Check for space character. */
if (media_ptr -> fx_media_memory_buffer[offset + (UINT)j] != (UCHAR)' ')
{
/* Last character found. */
break;
}
}
/* Check if the buffer is too short for the name. */
if (j >= (INT)volume_name_buffer_length - 1)
{
/* Buffer too short, return error. */
status = FX_BUFFER_ERROR;
/* Set character count to fit for the buffer. */
j = (INT)volume_name_buffer_length - 2;
}
/* NULL terminate the volume name. */
volume_name[j + 1] = FX_NULL;
/* Pickup the remaining characters of the volume name from the boot sector. */
for (; j >= 0; j--)
{
/* Pickup byte of volume name. */
volume_name[j] = (CHAR)media_ptr -> fx_media_memory_buffer[offset + (UINT)j];
}
/* Release media protection. */
FX_UNPROTECT
/* Return the completion status. */
return(status);
}
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