diff options
Diffstat (limited to 'c/src/libfs/src/imfs/memfile.c')
| -rw-r--r-- | c/src/libfs/src/imfs/memfile.c | 1137 |
1 files changed, 0 insertions, 1137 deletions
diff --git a/c/src/libfs/src/imfs/memfile.c b/c/src/libfs/src/imfs/memfile.c deleted file mode 100644 index cfa37c20c6..0000000000 --- a/c/src/libfs/src/imfs/memfile.c +++ /dev/null @@ -1,1137 +0,0 @@ -/* - * IMFS Device Node Handlers - * - * This file contains the set of handlers used to process operations on - * IMFS memory file nodes. The memory files are created in memory using - * malloc'ed memory. Thus any data stored in one of these files is lost - * at system shutdown unless special arrangements to copy the data to - * some type of non-volailte storage are made by the application. - * - * COPYRIGHT (c) 1989-1999. - * On-Line Applications Research Corporation (OAR). - * - * The license and distribution terms for this file may be - * found in the file LICENSE in this distribution or at - * http://www.OARcorp.com/rtems/license.html. - * - * $Id$ - */ - -#if HAVE_CONFIG_H -#include "config.h" -#endif - -#include <stdlib.h> -#include <string.h> -#include <assert.h> -#include <errno.h> - -#include <rtems.h> -#include <rtems/libio.h> -#include "imfs.h" -#include <rtems/libio_.h> -#include <rtems/seterr.h> - -#define MEMFILE_STATIC - -/* - * Prototypes of private routines - */ - -MEMFILE_STATIC int IMFS_memfile_extend( - IMFS_jnode_t *the_jnode, - off_t new_length -); - -MEMFILE_STATIC int IMFS_memfile_addblock( - IMFS_jnode_t *the_jnode, - unsigned int block -); - -MEMFILE_STATIC int IMFS_memfile_remove_block( - IMFS_jnode_t *the_jnode, - unsigned int block -); - -MEMFILE_STATIC block_p *IMFS_memfile_get_block_pointer( - IMFS_jnode_t *the_jnode, - unsigned int block, - int malloc_it -); - -MEMFILE_STATIC int IMFS_memfile_read( - IMFS_jnode_t *the_jnode, - off_t start, - unsigned char *destination, - unsigned int length -); - -MEMFILE_STATIC int IMFS_memfile_write( - IMFS_jnode_t *the_jnode, - off_t start, - const unsigned char *source, - unsigned int length -); - -void *memfile_alloc_block(void); - -void memfile_free_block( - void *memory -); - -/* - * memfile_open - * - * This routine processes the open() system call. Note that there is - * nothing special to be done at open() time. - */ - -int memfile_open( - rtems_libio_t *iop, - const char *pathname, - unsigned32 flag, - unsigned32 mode -) -{ - IMFS_jnode_t *the_jnode; - - the_jnode = iop->file_info; - - if (iop->flags & LIBIO_FLAGS_APPEND) - iop->offset = the_jnode->info.file.size; - - iop->size = the_jnode->info.file.size; - return 0; -} - -/* - * memfile_close - * - * This routine processes the close() system call. Note that there is - * nothing to flush or memory to free at this point. - */ - -int memfile_close( - rtems_libio_t *iop -) -{ - IMFS_jnode_t *the_jnode; - - the_jnode = iop->file_info; - - if (iop->flags & LIBIO_FLAGS_APPEND) - iop->offset = the_jnode->info.file.size; - - return 0; -} - -/* - * memfile_read - * - * This routine processes the read() system call. - */ - -int memfile_read( - rtems_libio_t *iop, - void *buffer, - unsigned32 count -) -{ - IMFS_jnode_t *the_jnode; - - the_jnode = iop->file_info; - - return IMFS_memfile_read( the_jnode, iop->offset, buffer, count ); -} - -/* - * memfile_write - * - * This routine processes the write() system call. - */ - -int memfile_write( - rtems_libio_t *iop, - const void *buffer, - unsigned32 count -) -{ - IMFS_jnode_t *the_jnode; - int status; - - the_jnode = iop->file_info; - - status = IMFS_memfile_write( the_jnode, iop->offset, buffer, count ); - iop->size = the_jnode->info.file.size; - - return status; -} - -/* - * memfile_ioctl - * - * This routine processes the ioctl() system call. - * - * NOTE: No ioctl()'s are supported for in-memory files. - */ - -int memfile_ioctl( - rtems_libio_t *iop, - unsigned32 command, - void *buffer -) -{ - IMFS_jnode_t *the_jnode; - - the_jnode = iop->file_info; - - return 0; -} - -/* - * memfile_lseek - * - * This routine processes the lseek() system call. - */ - -int memfile_lseek( - rtems_libio_t *iop, - off_t offset, - int whence -) -{ - IMFS_jnode_t *the_jnode; - - the_jnode = iop->file_info; - - if (the_jnode->type == IMFS_LINEAR_FILE) { - if (iop->offset > the_jnode->info.linearfile.size) - iop->offset = the_jnode->info.linearfile.size; - } - else { /* Must be a block file (IMFS_MEMORY_FILE). */ - if (IMFS_memfile_extend( the_jnode, iop->offset )) - rtems_set_errno_and_return_minus_one( ENOSPC ); - - iop->size = the_jnode->info.file.size; - } - return iop->offset; -} - -/* - * memfile_stat - * - * This IMFS_stat() can be used. - */ - -/* - * memfile_ftruncate - * - * This routine processes the ftruncate() system call. - */ - -int memfile_ftruncate( - rtems_libio_t *iop, - off_t length -) -{ - IMFS_jnode_t *the_jnode; - - the_jnode = iop->file_info; - - /* - * POSIX 1003.1b does not specify what happens if you truncate a file - * and the new length is greater than the current size. We treat this - * as an extend operation. - */ - - if ( length > the_jnode->info.file.size ) - return IMFS_memfile_extend( the_jnode, length ); - - /* - * The in-memory files do not currently reclaim memory until the file is - * deleted. So we leave the previously allocated blocks in place for - * future use and just set the length. - */ - - the_jnode->info.file.size = length; - iop->size = the_jnode->info.file.size; - - IMFS_update_atime( the_jnode ); - - return 0; -} - -/* - * IMFS_memfile_extend - * - * This routine insures that the in-memory file is of the length - * specified. If necessary, it will allocate memory blocks to - * extend the file. - */ - -MEMFILE_STATIC int IMFS_memfile_extend( - IMFS_jnode_t *the_jnode, - off_t new_length -) -{ - unsigned int block; - unsigned int new_blocks; - unsigned int old_blocks; - - /* - * Perform internal consistency checks - */ - - assert( the_jnode ); - if ( !the_jnode ) - rtems_set_errno_and_return_minus_one( EIO ); - - assert( the_jnode->type == IMFS_MEMORY_FILE ); - if ( the_jnode->type != IMFS_MEMORY_FILE ) - rtems_set_errno_and_return_minus_one( EIO ); - - if ( new_length >= IMFS_MEMFILE_MAXIMUM_SIZE ) - rtems_set_errno_and_return_minus_one( EINVAL ); - - if ( new_length <= the_jnode->info.file.size ) - return 0; - - /* - * Calculate the number of range of blocks to allocate - */ - - new_blocks = new_length / IMFS_MEMFILE_BYTES_PER_BLOCK; - old_blocks = the_jnode->info.file.size / IMFS_MEMFILE_BYTES_PER_BLOCK; - - /* - * Now allocate each of those blocks. - */ - - for ( block=old_blocks ; block<=new_blocks ; block++ ) { - if ( IMFS_memfile_addblock( the_jnode, block ) ) { - for ( ; block>=old_blocks ; block-- ) { - IMFS_memfile_remove_block( the_jnode, block ); - } - rtems_set_errno_and_return_minus_one( ENOSPC ); - } - } - - /* - * Set the new length of the file. - */ - - the_jnode->info.file.size = new_length; - return 0; -} - -/* - * IMFS_memfile_addblock - * - * This routine adds a single block to the specified in-memory file. - */ - -MEMFILE_STATIC int IMFS_memfile_addblock( - IMFS_jnode_t *the_jnode, - unsigned int block -) -{ - block_p memory; - block_p *block_entry_ptr; - - assert( the_jnode ); - if ( !the_jnode ) - rtems_set_errno_and_return_minus_one( EIO ); - - assert( the_jnode->type == IMFS_MEMORY_FILE ); - if ( the_jnode->type != IMFS_MEMORY_FILE ) - rtems_set_errno_and_return_minus_one( EIO ); - - block_entry_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 1 ); - if ( *block_entry_ptr ) - return 0; - -#if 0 - printf( "%d %p", block, block_entry_ptr ); - fflush(stdout); -#endif - - memory = memfile_alloc_block(); - if ( !memory ) - return 1; - *block_entry_ptr = memory; - - return 0; -} - -/* - * IMFS_memfile_remove_block - * - * This routine removes the specified block from the in-memory file. - * - * NOTE: This is a support routine and is called only to remove - * the last block or set of blocks in a file. Removing a - * block from the middle of a file would be exceptionally - * dangerous and the results unpredictable. - */ - -MEMFILE_STATIC int IMFS_memfile_remove_block( - IMFS_jnode_t *the_jnode, - unsigned int block -) -{ - block_p *block_entry_ptr; - block_p ptr; - - block_entry_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); - ptr = *block_entry_ptr; - *block_entry_ptr = 0; - - memfile_free_block( ptr ); - - return 1; -} - -/* - * memfile_free_blocks_in_table - * - * This is a support routine for IMFS_memfile_remove. It frees all the - * blocks in one of the indirection tables. - */ - -void memfile_free_blocks_in_table( - block_p **block_table, - int entries -) -{ - int i; - block_p *b; - - /* - * Perform internal consistency checks - */ - - assert( block_table ); - if ( !block_table ) - return; - - /* - * Now go through all the slots in the table and free the memory. - */ - - b = *block_table; - - for ( i=0 ; i<entries ; i++ ) { - if ( b[i] ) { - memfile_free_block( b[i] ); - b[i] = 0; - } - } - - /* - * Now that all the blocks in the block table are free, we can - * free the block table itself. - */ - - memfile_free_block( *block_table ); - *block_table = 0; -} - -/* - * IMFS_memfile_remove - * - * This routine frees all memory associated with an in memory file. - * - * NOTE: This is an exceptionally conservative implementation. - * It will check EVERY pointer which is non-NULL and insure - * any child non-NULL pointers are freed. Optimistically, all that - * is necessary is to scan until a NULL pointer is found. There - * should be no allocated data past that point. - * - * In experimentation on the powerpc simulator, it was noted - * that using blocks which held 128 slots versus 16 slots made - * a significant difference in the performance of this routine. - * - * Regardless until the IMFS implementation is proven, it - * is better to stick to simple, easy to understand algorithms. - */ - -int IMFS_memfile_remove( - IMFS_jnode_t *the_jnode -) -{ - IMFS_memfile_t *info; - int i; - int j; - unsigned int to_free; - block_p *p; - - /* - * Perform internal consistency checks - */ - - assert( the_jnode ); - if ( !the_jnode ) - rtems_set_errno_and_return_minus_one( EIO ); - - assert( the_jnode->type == IMFS_MEMORY_FILE ); - if ( the_jnode->type != IMFS_MEMORY_FILE ) - rtems_set_errno_and_return_minus_one( EIO ); - - /* - * Eventually this could be set smarter at each call to - * memfile_free_blocks_in_table to greatly speed this up. - */ - - to_free = IMFS_MEMFILE_BLOCK_SLOTS; - - /* - * Now start freeing blocks in this order: - * + indirect - * + doubly indirect - * + triply indirect - */ - - info = &the_jnode->info.file; - - if ( info->indirect ) { - memfile_free_blocks_in_table( &info->indirect, to_free ); - } - - if ( info->doubly_indirect ) { - - for ( i=0 ; i<IMFS_MEMFILE_BLOCK_SLOTS ; i++ ) { - if ( info->doubly_indirect[i] ) { - memfile_free_blocks_in_table( - (block_p **)&info->doubly_indirect[i], to_free ); - } - } - memfile_free_blocks_in_table( &info->doubly_indirect, to_free ); - - } - - if ( info->triply_indirect ) { - for ( i=0 ; i<IMFS_MEMFILE_BLOCK_SLOTS ; i++ ) { - p = (block_p *) info->triply_indirect[i]; - if ( !p ) /* ensure we have a valid pointer */ - break; - for ( j=0 ; j<IMFS_MEMFILE_BLOCK_SLOTS ; j++ ) { - if ( p[j] ) { - memfile_free_blocks_in_table( (block_p **)&p[j], to_free); - } - } - memfile_free_blocks_in_table( - (block_p **)&info->triply_indirect[i], to_free ); - } - memfile_free_blocks_in_table( - (block_p **)&info->triply_indirect, to_free ); - } - - return 0; -} - -/* - * IMFS_memfile_read - * - * This routine read from memory file pointed to by the_jnode into - * the specified data buffer specified by destination. The file - * is NOT extended. An offset greater than the length of the file - * is considered an error. Read from an offset for more bytes than - * are between the offset and the end of the file will result in - * reading the data between offset and the end of the file (truncated - * read). - */ - -MEMFILE_STATIC int IMFS_memfile_read( - IMFS_jnode_t *the_jnode, - off_t start, - unsigned char *destination, - unsigned int length -) -{ - block_p *block_ptr; - unsigned int block; - unsigned int my_length; - unsigned int to_copy = 0; - unsigned int last_byte; - unsigned int copied; - unsigned int start_offset; - unsigned char *dest; - - dest = destination; - - /* - * Perform internal consistency checks - */ - - assert( the_jnode ); - if ( !the_jnode ) - rtems_set_errno_and_return_minus_one( EIO ); - - assert( the_jnode->type == IMFS_MEMORY_FILE || - the_jnode->type == IMFS_LINEAR_FILE ); - if ( the_jnode->type != IMFS_MEMORY_FILE && - the_jnode->type != IMFS_LINEAR_FILE ) - rtems_set_errno_and_return_minus_one( EIO ); - - /* - * Error checks on arguments - */ - - assert( dest ); - if ( !dest ) - rtems_set_errno_and_return_minus_one( EINVAL ); - - /* - * If there is nothing to read, then quick exit. - */ - - my_length = length; - if ( !my_length ) - rtems_set_errno_and_return_minus_one( EINVAL ); - - /* - * Linear files (as created from a tar file are easier to handle - * than block files). - */ - if (the_jnode->type == IMFS_LINEAR_FILE) { - unsigned char *file_ptr; - - file_ptr = (unsigned char *)the_jnode->info.linearfile.direct; - - if (my_length > (the_jnode->info.linearfile.size - start)) - my_length = the_jnode->info.linearfile.size - start; - - memcpy(dest, &file_ptr[start], my_length); - - IMFS_update_atime( the_jnode ); - - return my_length; - } - - /* - * If the last byte we are supposed to read is past the end of this - * in memory file, then shorten the length to read. - */ - - last_byte = start + length; - if ( last_byte > the_jnode->info.file.size ) - my_length = the_jnode->info.file.size - start; - - copied = 0; - - /* - * Three phases to the read: - * + possibly the last part of one block - * + all of zero of more blocks - * + possibly the first part of one block - */ - - /* - * Phase 1: possibly the last part of one block - */ - - start_offset = start % IMFS_MEMFILE_BYTES_PER_BLOCK; - block = start / IMFS_MEMFILE_BYTES_PER_BLOCK; - if ( start_offset ) { - to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK - start_offset; - if ( to_copy > my_length ) - to_copy = my_length; - block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); - assert( block_ptr ); - if ( !block_ptr ) - return copied; - memcpy( dest, &(*block_ptr)[ start_offset ], to_copy ); - dest += to_copy; - block++; - my_length -= to_copy; - copied += to_copy; - } - - /* - * Phase 2: all of zero of more blocks - */ - - to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK; - while ( my_length >= IMFS_MEMFILE_BYTES_PER_BLOCK ) { - block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); - assert( block_ptr ); - if ( !block_ptr ) - return copied; - memcpy( dest, &(*block_ptr)[ 0 ], to_copy ); - dest += to_copy; - block++; - my_length -= to_copy; - copied += to_copy; - } - - /* - * Phase 3: possibly the first part of one block - */ - - assert( my_length < IMFS_MEMFILE_BYTES_PER_BLOCK ); - - if ( my_length ) { - block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); - assert( block_ptr ); - if ( !block_ptr ) - return copied; - memcpy( dest, &(*block_ptr)[ 0 ], my_length ); - copied += my_length; - } - - IMFS_update_atime( the_jnode ); - - return copied; -} - -/* - * IMFS_memfile_write - * - * This routine writes the specified data buffer into the in memory - * file pointed to by the_jnode. The file is extended as needed. - */ - -MEMFILE_STATIC int IMFS_memfile_write( - IMFS_jnode_t *the_jnode, - off_t start, - const unsigned char *source, - unsigned int length -) -{ - block_p *block_ptr; - unsigned int block; - int status; - unsigned int my_length; - unsigned int to_copy = 0; - unsigned int last_byte; - unsigned int start_offset; - int copied; - const unsigned char *src; - - src = source; - - /* - * Perform internal consistency checks - */ - - assert( the_jnode ); - if ( !the_jnode ) - rtems_set_errno_and_return_minus_one( EIO ); - - assert( the_jnode->type == IMFS_MEMORY_FILE ); - if ( the_jnode->type != IMFS_MEMORY_FILE ) - rtems_set_errno_and_return_minus_one( EIO ); - - /* - * Error check arguments - */ - - assert( source ); - if ( !source ) - rtems_set_errno_and_return_minus_one( EINVAL ); - - - /* - * If there is nothing to write, then quick exit. - */ - - my_length = length; - if ( !my_length ) - rtems_set_errno_and_return_minus_one( EINVAL ); - - /* - * If the last byte we are supposed to write is past the end of this - * in memory file, then extend the length. - */ - - last_byte = start + length; - if ( last_byte > the_jnode->info.file.size ) { - status = IMFS_memfile_extend( the_jnode, last_byte ); - if ( status ) - rtems_set_errno_and_return_minus_one( ENOSPC ); - } - - copied = 0; - - /* - * Three phases to the write: - * + possibly the last part of one block - * + all of zero of more blocks - * + possibly the first part of one block - */ - - /* - * Phase 1: possibly the last part of one block - */ - - start_offset = start % IMFS_MEMFILE_BYTES_PER_BLOCK; - block = start / IMFS_MEMFILE_BYTES_PER_BLOCK; - if ( start_offset ) { - to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK - start_offset; - if ( to_copy > my_length ) - to_copy = my_length; - block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); - assert( block_ptr ); - if ( !block_ptr ) - return copied; -#if 0 -printf( "write %d at %d in %d: %*s\n", to_copy, start_offset, block, to_copy, src ); -#endif - memcpy( &(*block_ptr)[ start_offset ], src, to_copy ); - src += to_copy; - block++; - my_length -= to_copy; - copied += to_copy; - } - - /* - * Phase 2: all of zero of more blocks - */ - - to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK; - while ( my_length >= IMFS_MEMFILE_BYTES_PER_BLOCK ) { - block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); - assert( block_ptr ); - if ( !block_ptr ) - return copied; -#if 0 -printf( "write %d in %d: %*s\n", to_copy, block, to_copy, src ); -#endif - memcpy( &(*block_ptr)[ 0 ], src, to_copy ); - src += to_copy; - block++; - my_length -= to_copy; - copied += to_copy; - } - - /* - * Phase 3: possibly the first part of one block - */ - - assert( my_length < IMFS_MEMFILE_BYTES_PER_BLOCK ); - - to_copy = my_length; - if ( my_length ) { - block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); - assert( block_ptr ); - if ( !block_ptr ) - return copied; -#if 0 -printf( "write %d in %d: %*s\n", to_copy, block, to_copy, src ); -#endif - memcpy( &(*block_ptr)[ 0 ], src, my_length ); - my_length = 0; - copied += to_copy; - } - - IMFS_atime_mtime_update( the_jnode ); - - return copied; -} - -/* - * IMFS_memfile_get_block_pointer - * - * This routine looks up the block pointer associated with the given block - * number. If that block has not been allocated and "malloc_it" is - * TRUE, then the block is allocated. Otherwise, it is an error. - */ - -#if 0 -block_p *IMFS_memfile_get_block_pointer_DEBUG( - IMFS_jnode_t *the_jnode, - unsigned int block, - int malloc_it -); - -block_p *IMFS_memfile_get_block_pointer( - IMFS_jnode_t *the_jnode, - unsigned int block, - int malloc_it -) -{ - block_p *p; - - p = IMFS_memfile_get_block_pointer_DEBUG( the_jnode, block, malloc_it ); - printf( "(%d -> %p) ", block, p ); - return p; -} - -block_p *IMFS_memfile_get_block_pointer_DEBUG( -#else -block_p *IMFS_memfile_get_block_pointer( -#endif - IMFS_jnode_t *the_jnode, - unsigned int block, - int malloc_it -) -{ - unsigned int my_block; - IMFS_memfile_t *info; - unsigned int singly; - unsigned int doubly; - unsigned int triply; - block_p *p; - block_p *p1; - block_p *p2; - - /* - * Perform internal consistency checks - */ - - assert( the_jnode ); - if ( !the_jnode ) - return NULL; - - assert( the_jnode->type == IMFS_MEMORY_FILE ); - if ( the_jnode->type != IMFS_MEMORY_FILE ) - return NULL; - - info = &the_jnode->info.file; - - my_block = block; - - /* - * Is the block number in the simple indirect portion? - */ - - if ( my_block <= LAST_INDIRECT ) { -#if 0 -printf( "(s %d) ", block ); -fflush(stdout); -#endif - p = info->indirect; - - if ( malloc_it ) { - - if ( !p ) { - p = memfile_alloc_block(); - if ( !p ) - return 0; - info->indirect = p; - } - return &info->indirect[ my_block ]; - } - - if ( !p ) - return 0; - - return &info->indirect[ my_block ]; - } - - /* - * Is the block number in the doubly indirect portion? - */ - - if ( my_block <= LAST_DOUBLY_INDIRECT ) { -#if 0 -printf( "(d %d) ", block ); -fflush(stdout); -#endif - - my_block -= FIRST_DOUBLY_INDIRECT; - - singly = my_block % IMFS_MEMFILE_BLOCK_SLOTS; - doubly = my_block / IMFS_MEMFILE_BLOCK_SLOTS; - - p = info->doubly_indirect; - if ( malloc_it ) { - - if ( !p ) { - p = memfile_alloc_block(); - if ( !p ) - return 0; - info->doubly_indirect = p; - } - - p1 = (block_p *)p[ doubly ]; - if ( !p1 ) { - p1 = memfile_alloc_block(); - if ( !p1 ) - return 0; - p[ doubly ] = (block_p) p1; - } - - return (block_p *)&p1[ singly ]; - } - - if ( !p ) - return 0; - - p = (block_p *)p[ doubly ]; - if ( !p ) - return 0; - -#if 0 -printf( "(d %d %d %d %d %p %p) ", block, my_block, doubly, - singly, p, &p[singly] ); -fflush(stdout); -#endif - return (block_p *)&p[ singly ]; - } - -#if 0 -printf( "(t %d) ", block ); -fflush(stdout); -#endif - /* - * Is the block number in the triply indirect portion? - */ - - if ( my_block <= LAST_TRIPLY_INDIRECT ) { - my_block -= FIRST_TRIPLY_INDIRECT; - - singly = my_block % IMFS_MEMFILE_BLOCK_SLOTS; - doubly = my_block / IMFS_MEMFILE_BLOCK_SLOTS; - triply = doubly / IMFS_MEMFILE_BLOCK_SLOTS; - doubly %= IMFS_MEMFILE_BLOCK_SLOTS; - - p = info->triply_indirect; - - if ( malloc_it ) { - if ( !p ) { - p = memfile_alloc_block(); - if ( !p ) - return 0; - info->triply_indirect = p; - } - - p1 = (block_p *) p[ triply ]; - if ( !p1 ) { - p1 = memfile_alloc_block(); - if ( !p1 ) - return 0; - p[ triply ] = (block_p) p1; - } - - p2 = (block_p *)p1[ doubly ]; - if ( !p2 ) { - p2 = memfile_alloc_block(); - if ( !p2 ) - return 0; - p1[ doubly ] = (block_p) p2; - } - return (block_p *)&p2[ singly ]; - } - - if ( !p ) - return 0; - -#if 0 -printf( "(t %d %d %d %d %d) ", block, my_block, triply, doubly, singly ); -fflush(stdout); -#endif - p1 = (block_p *) p[ triply ]; - if ( !p1 ) - return 0; - - p2 = (block_p *)p1[ doubly ]; - if ( !p ) - return 0; - - return (block_p *)&p2[ singly ]; - } - - /* - * This means the requested block number is out of range. - */ - - return 0; -} - -/* - * memfile_alloc_block - * - * Allocate a block for an in-memory file. - */ - -int memfile_blocks_allocated = 0; - -void *memfile_alloc_block(void) -{ - void *memory; - - memory = (void *)calloc(1, IMFS_MEMFILE_BYTES_PER_BLOCK); - if ( memory ) - memfile_blocks_allocated++; - - return memory; -} - -/* - * memfile_free_block - * - * Free a block from an in-memory file. - */ - -void memfile_free_block( - void *memory -) -{ -#if 0 -printf( "(d %p) ", memory ); -fflush(stdout); -#endif - free(memory); - memfile_blocks_allocated--; -} - - -/* - * memfile_rmnod - * - * This routine is available from the optable to remove a node - * from the IMFS file system. - */ - -int memfile_rmnod( - rtems_filesystem_location_info_t *pathloc /* IN */ -) -{ - IMFS_jnode_t *the_jnode; - - the_jnode = (IMFS_jnode_t *) pathloc->node_access; - - /* - * Take the node out of the parent's chain that contains this node - */ - - if ( the_jnode->Parent != NULL ) { - Chain_Extract( (Chain_Node *) the_jnode ); - the_jnode->Parent = NULL; - } - - /* - * Decrement the link counter and see if we can free the space. - */ - - the_jnode->st_nlink--; - IMFS_update_ctime( the_jnode ); - - /* - * The file cannot be open and the link must be less than 1 to free. - */ - - if ( !rtems_libio_is_file_open( the_jnode ) && (the_jnode->st_nlink < 1) ) { - - /* - * Is the rtems_filesystem_current is this node? - */ - - if ( rtems_filesystem_current.node_access == pathloc->node_access ) - rtems_filesystem_current.node_access = NULL; - - /* - * Free memory associated with a memory file. - */ - if (the_jnode->type != IMFS_LINEAR_FILE) - IMFS_memfile_remove( the_jnode ); - - free( the_jnode ); - } - - return 0; - -} - - |