Code to compute position of directory records and path tables.

This commit is contained in:
Vreixo Formoso 2007-12-18 00:20:03 +01:00
parent 5e2de57aa9
commit 257b08bfcf
3 changed files with 115 additions and 3 deletions

View File

@ -13,11 +13,13 @@
#include "filesrc.h"
#include "image.h"
#include "writer.h"
#include "util.h"
#include "libburn/libburn.h"
#include <stdlib.h>
#include <time.h>
#include <string.h>
static
void ecma119_image_free(Ecma119Image *t)
@ -37,11 +39,108 @@ void ecma119_image_free(Ecma119Image *t)
free(t);
}
/**
* Compute the size of a directory entry for a single node
*/
static
size_t calc_dirent_len(Ecma119Node *n)
{
int ret = n->iso_name ? strlen(n->iso_name) + 33 : 34;
if (ret % 2) ret++;
return ret;
}
/**
* Computes the total size of all directory entries of a single dir,
* acording to ECMA-119 6.8.1.1
*/
static
size_t calc_dir_size(Ecma119Image *t, Ecma119Node *dir)
{
size_t i, len;
t->ndirs++;
/* size of "." and ".." entries */
len = 34 + 34;
for (i = 0; i < dir->info.dir.nchildren; ++i) {
Ecma119Node *child = dir->info.dir.children[i];
size_t dirent_len = calc_dirent_len(child);
size_t remaining = BLOCK_SIZE - (len % BLOCK_SIZE);
if (dirent_len > remaining) {
/* child directory entry doesn't fit on block */
len += remaining + dirent_len;
} else {
len += dirent_len;
}
}
return len;
}
static
void calc_dir_pos(Ecma119Image *t, Ecma119Node *dir)
{
size_t i, len;
dir->info.dir.block = t->curblock;
len = calc_dir_size(t, dir);
t->curblock += div_up(len, BLOCK_SIZE);
for (i = 0; i < dir->info.dir.nchildren; i++) {
Ecma119Node *child = dir->info.dir.children[i];
if (child->type == ECMA119_DIR) {
calc_dir_pos(t, child);
}
}
}
static
int ecma119_writer_compute_data_blocks(IsoImageWriter *writer)
{
//TODO to implement
return -1;
Ecma119Image *target;
Ecma119Node **pathlist;
uint32_t path_table_size;
size_t i, j, cur;
if (writer == NULL) {
return ISO_MEM_ERROR;
}
target = writer->target;
/* compute position of directories */
target->ndirs = 0;
calc_dir_pos(target, target->root);
/* compute length of pathlist */
pathlist = calloc(1, sizeof(void*) * target->ndirs);
if (pathlist == NULL) {
return ISO_MEM_ERROR;
}
pathlist[0] = target->root;
path_table_size = 10; /* root directory record */
cur = 1;
for (i = 0; i < target->ndirs; i++) {
Ecma119Node *dir = pathlist[i];
for (j = 0; j < dir->info.dir.nchildren; j++) {
Ecma119Node *child = dir->info.dir.children[j];
if (child->type == ECMA119_DIR) {
size_t len = 8 + strlen(child->iso_name);
pathlist[cur++] = child;
path_table_size += len + len % 2;
}
}
}
/* compute location for path tables */
target->l_path_table_pos = target->curblock;
target->curblock += div_up(path_table_size, BLOCK_SIZE);
target->m_path_table_pos = target->curblock;
target->curblock += div_up(path_table_size, BLOCK_SIZE);
/* ...and free path table cache, as we do not need it at all */
free(pathlist);
return ISO_SUCCESS;
}
static
@ -112,6 +211,7 @@ int ecma119_image_new(IsoImage *src, Ecma119WriteOpts *opts,
iso_image_ref(src);
target->iso_level = opts->level;
target->sort_files = opts->sort_files;
target->now = time(NULL);

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@ -13,6 +13,8 @@
#include <stdint.h>
#define BLOCK_SIZE 2048
typedef struct ecma119_image Ecma119Image;
typedef struct ecma119_node Ecma119Node;
typedef struct Iso_File_Src IsoFileSrc;
@ -40,6 +42,8 @@ struct ecma119_image {
// mode_t file_mode;
// gid_t gid;
// uid_t uid;
int sort_files; /**< if sort files or not. Sorting is based of
* the weight of each file */
time_t now; /**< Time at which writing began. */
@ -53,6 +57,14 @@ struct ecma119_image {
*/
uint32_t curblock;
/*
* number of dirs in ECMA-119 tree, computed together with dir position,
* and needed for path table computation in a efficient way
*/
size_t ndirs;
uint32_t l_path_table_pos;
uint32_t m_path_table_pos;
size_t nwriters;
IsoImageWriter **writers;

View File

@ -71,7 +71,7 @@ typedef struct {
* its size. In those cases, we only copy 1 block of data.
*/
//unsigned int sort_files:1;
unsigned int sort_files:1;
/**< If files should be sorted based on their weight. */
// unsigned int default_mode:1;
// /**<