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free_alloc_chain() bugfix

master
A 2020-05-02 19:06:43 -07:00
parent ebbcc9dd44
commit 416f0e372e
1 changed files with 7 additions and 2 deletions
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7
filesystem.c
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@ -423,6 +423,8 @@ int fs_truncate(int fildes, off_t length)
fat_idx = fat->table[fat_idx]; fat_idx = fat->table[fat_idx];
free_alloc_chain(fat_idx); free_alloc_chain(fat_idx);
fat->table[eof_idx] = FAT_EOF; fat->table[eof_idx] = FAT_EOF;
memset(disk + eof_idx * BLOCK_SIZE + length % BLOCK_SIZE, 0,
BLOCK_SIZE - (length % BLOCK_SIZE));
descriptors[idx].attr->size = length; descriptors[idx].attr->size = length;
// ptr to final byte of truncated file // ptr to final byte of truncated file
@ -534,13 +536,16 @@ int free_alloc_chain(int head)
memset(disk + head * BLOCK_SIZE, 0, BLOCK_SIZE); memset(disk + head * BLOCK_SIZE, 0, BLOCK_SIZE);
/* either unused or probably hit the end of the chain */ /* either unused or probably hit the end of the chain */
if (idx == FAT_UNUSED || idx == FAT_EOF) if (idx == FAT_UNUSED)
{ {
return 0; return 0;
} }
fat->table[head] = FAT_UNUSED; fat->table[head] = FAT_UNUSED;
if (idx != FAT_EOF)
return free_alloc_chain(idx); return free_alloc_chain(idx);
else
return 0;
} }
int find_avail_alloc_entry() int find_avail_alloc_entry()