libisofs-legacy/libisofs/susp.c
2007-07-31 07:32:26 +00:00

257 lines
5.9 KiB
C
Executable File

/* vim: set noet ts=8 sts=8 sw=8 : */
#include "susp.h"
#include "util.h"
#include "ecma119.h"
#include "ecma119_tree.h"
#include <stdlib.h>
#include <assert.h>
#include <string.h>
void susp_insert(struct ecma119_write_target *t,
struct susp_info *susp,
uint8_t *data,
int pos)
{
int i;
if (pos < 0) {
pos = susp->n_susp_fields;
}
assert(pos <= susp->n_susp_fields);
susp->n_susp_fields++;
susp->susp_fields = realloc(susp->susp_fields,
sizeof(void*) * susp->n_susp_fields);
for (i = susp->n_susp_fields-1; i > pos; i--) {
susp->susp_fields[i] = susp->susp_fields[i - 1];
}
susp->susp_fields[pos] = data;
}
void susp_append(struct ecma119_write_target *t,
struct susp_info *susp,
uint8_t *data)
{
susp_insert(t, susp, data, susp->n_susp_fields);
}
uint8_t *susp_find(struct susp_info *susp, const char *name)
{
int i;
for (i = 0; i < susp->n_susp_fields; i++) {
if (!strncmp((char *)susp->susp_fields[i], name, 2)) {
return susp->susp_fields[i];
}
}
return NULL;
}
/** Utility function for susp_add_CE because susp_add_CE needs to act 3 times
* on directories (for the "." and ".." entries.
*
* \param len The amount of space available for the System Use area.
*/
#define CE_LEN 28
static unsigned char *susp_add_single_CE(struct ecma119_write_target *t,
struct susp_info *susp,
int len)
{
int susp_length = 0, tmp_len;
int i;
unsigned char *CE;
for (i = 0; i < susp->n_susp_fields; i++) {
susp_length += susp->susp_fields[i][2];
}
if (susp_length <= len) {
/* no need for a CE field */
susp->non_CE_len = susp_length;
susp->n_fields_fit = susp->n_susp_fields;
return NULL;
}
tmp_len = susp_length;
for (i = susp->n_susp_fields - 1; i >= 0; i--) {
tmp_len -= susp->susp_fields[i][2];
if (tmp_len + CE_LEN <= len) {
susp->non_CE_len = tmp_len + CE_LEN;
susp->CE_len = susp_length - tmp_len;
/* i+1 because we have to count the CE field */
susp->n_fields_fit = i + 1;
CE = calloc(1, CE_LEN);
/* we don't fill in the BLOCK LOCATION or OFFSET
fields yet. */
CE[0] = 'C';
CE[1] = 'E';
CE[2] = (char)CE_LEN;
CE[3] = (char)1;
iso_bb(&CE[20], susp_length - tmp_len, 4);
return CE;
}
}
assert(0);
return NULL;
}
static void
try_add_CE(struct ecma119_write_target *t,
struct susp_info *susp,
size_t dirent_len)
{
uint8_t *CE = susp_add_single_CE(t, susp, 255 - dirent_len);
if (CE)
susp_insert(t, susp, CE, susp->n_fields_fit - 1);
}
/** See IEEE P1281 Draft Version 1.12/5.2. Because this function depends on the
* length of the other SUSP fields, it should always be calculated last. */
void
susp_add_CE(struct ecma119_write_target *t, struct ecma119_tree_node *node)
{
try_add_CE(t, &node->susp, node->dirent_len);
if (node->type == ECMA119_DIR) {
try_add_CE(t, &node->info.dir.self_susp, 34);
try_add_CE(t, &node->info.dir.parent_susp, 34);
}
}
/** See IEEE P1281 Draft Version 1.12/5.3 */
void
susp_add_SP(struct ecma119_write_target *t, struct ecma119_tree_node *dir)
{
unsigned char *SP = malloc(7);
assert(dir->type == ECMA119_DIR);
SP[0] = 'S';
SP[1] = 'P';
SP[2] = (char)7;
SP[3] = (char)1;
SP[4] = 0xbe;
SP[5] = 0xef;
SP[6] = 0;
susp_append(t, &dir->info.dir.self_susp, SP);
}
#if 0
/** See IEEE P1281 Draft Version 1.12/5.4 */
static void susp_add_ST(struct ecma119_write_target *t,
struct iso_tree_node *node)
{
unsigned char *ST = malloc(4);
ST[0] = 'S';
ST[1] = 'T';
ST[2] = (char)4;
ST[3] = (char)1;
susp_append(t, node, ST);
}
#endif
/* calculate the location of the CE areas. Since CE areas don't need to be
* aligned to a block boundary, we contatenate all CE areas from a single
* directory and dump them immediately after all the directory records.
*
* Requires that the following be known:
* - position of the current directory (dir->info.dir.block)
* - length of the current directory (dir->info.dir.len)
* - sum of the children's CE lengths (dir->info.dir.CE_len)
*/
static void
susp_fin_1_CE(struct ecma119_write_target *t,
struct susp_info *susp,
size_t block,
size_t *offset)
{
uint8_t *CE = susp->susp_fields[susp->n_fields_fit - 1];
if (!susp->CE_len) {
return;
}
iso_bb(&CE[4], block + (*offset) / t->block_size, 4);
iso_bb(&CE[12], (*offset) % t->block_size, 4);
*offset += susp->CE_len;
}
static void susp_fin_CE(struct ecma119_write_target *t,
struct ecma119_tree_node *dir)
{
int i;
size_t CE_offset = dir->info.dir.len;
assert(dir->type == ECMA119_DIR);
susp_fin_1_CE(t, &dir->info.dir.self_susp, dir->info.dir.block, &CE_offset);
susp_fin_1_CE(t, &dir->info.dir.parent_susp, dir->info.dir.block, &CE_offset);
for (i = 0; i < dir->info.dir.nchildren; i++) {
struct ecma119_tree_node *ch = dir->info.dir.children[i];
susp_fin_1_CE(t, &ch->susp, dir->info.dir.block, &CE_offset);
}
assert(CE_offset == dir->info.dir.len + dir->info.dir.CE_len);
}
void
susp_finalize(struct ecma119_write_target *t, struct ecma119_tree_node *dir)
{
int i;
assert(dir->type = ECMA119_DIR);
if (dir->info.dir.depth != 1) {
susp_fin_CE(t, dir);
}
for (i = 0; i < dir->info.dir.nchildren; i++) {
if (dir->info.dir.children[i]->type == ECMA119_DIR)
susp_finalize(t, dir->info.dir.children[i]);
}
}
void susp_write(struct ecma119_write_target *t,
struct susp_info *susp,
unsigned char *buf)
{
int i;
int pos = 0;
for (i = 0; i < susp->n_fields_fit; i++) {
memcpy(&buf[pos], susp->susp_fields[i],
susp->susp_fields[i][2]);
pos += susp->susp_fields[i][2];
}
}
void susp_write_CE(struct ecma119_write_target *t, struct susp_info *susp,
unsigned char *buf)
{
int i;
int pos = 0;
for (i = susp->n_fields_fit; i < susp->n_susp_fields; i++) {
memcpy(&buf[pos], susp->susp_fields[i],
susp->susp_fields[i][2]);
pos += susp->susp_fields[i][2];
}
}
void susp_free_fields(struct susp_info *susp)
{
int i;
for (i=0; i<susp->n_susp_fields; i++) {
free(susp->susp_fields[i]);
}
if (susp->susp_fields) {
free(susp->susp_fields);
}
memset(susp, 0, sizeof(struct susp_info));
}