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libisofs/src/tree.c

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/*
* Copyright (c) 2007 Vreixo Formoso
*
* This file is part of the libisofs project; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation. See COPYING file for details.
*/
/*
* Functions that act on the iso tree.
*/
#include "libisofs.h"
#include "node.h"
#include "error.h"
#include "image.h"
#include "fsource.h"
#include "builder.h"
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <limits.h>
/**
* Add a new directory to the iso tree.
*
* @param parent
* the dir where the new directory will be created
* @param name
* name for the new dir. If a node with same name already exists on
* parent, this functions fails with ISO_NODE_NAME_NOT_UNIQUE.
* @param dir
* place where to store a pointer to the newly created dir. No extra
* ref is addded, so you will need to call iso_node_ref() if you really
* need it. You can pass NULL in this parameter if you don't need the
* pointer.
* @return
* number of nodes in dir if succes, < 0 otherwise
* Possible errors:
* ISO_NULL_POINTER, if parent or name are NULL
* ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
*/
int iso_tree_add_new_dir(IsoDir *parent, const char *name, IsoDir **dir)
{
IsoDir *node;
IsoNode **pos;
time_t now;
if (parent == NULL || name == NULL) {
return ISO_NULL_POINTER;
}
if (dir) {
*dir = NULL;
}
/* find place where to insert */
pos = &(parent->children);
while (*pos != NULL && strcmp((*pos)->name, name) < 0) {
pos = &((*pos)->next);
}
if (*pos != NULL && !strcmp((*pos)->name, name)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
node = calloc(1, sizeof(IsoDir));
if (node == NULL) {
return ISO_MEM_ERROR;
}
node->node.refcount = 1;
node->node.type = LIBISO_DIR;
node->node.name = strdup(name);
if (node->node.name == NULL) {
free(node);
return ISO_MEM_ERROR;
}
/* permissions from parent */
node->node.mode = parent->node.mode;
node->node.uid = parent->node.uid;
node->node.gid = parent->node.gid;
node->node.hidden = parent->node.hidden;
/* current time */
now = time(NULL);
node->node.atime = now;
node->node.ctime = now;
node->node.mtime = now;
/* add to dir */
node->node.parent = parent;
node->node.next = *pos;
*pos = (IsoNode*)node;
if (dir) {
*dir = node;
}
return ++parent->nchildren;
}
/**
* Add a new symlink to the directory tree. Permissions are set to 0777,
* owner and hidden atts are taken from parent. You can modify any of them
* later.
*
* @param parent
* the dir where the new symlink will be created
* @param name
* name for the new dir. If a node with same name already exists on
* parent, this functions fails with ISO_NODE_NAME_NOT_UNIQUE.
* @param dest
* destination of the link
* @param link
* place where to store a pointer to the newly created link. No extra
* ref is addded, so you will need to call iso_node_ref() if you really
* need it. You can pass NULL in this parameter if you don't need the
* pointer
* @return
* number of nodes in parent if success, < 0 otherwise
* Possible errors:
* ISO_NULL_POINTER, if parent, name or dest are NULL
* ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
* ISO_MEM_ERROR
*/
int iso_tree_add_new_symlink(IsoDir *parent, const char *name,
const char *dest, IsoSymlink **link)
{
IsoSymlink *node;
IsoNode **pos;
time_t now;
if (parent == NULL || name == NULL || dest == NULL) {
return ISO_NULL_POINTER;
}
if (link) {
*link = NULL;
}
/* find place where to insert */
pos = &(parent->children);
while (*pos != NULL && strcmp((*pos)->name, name) < 0) {
pos = &((*pos)->next);
}
if (*pos != NULL && !strcmp((*pos)->name, name)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
node = calloc(1, sizeof(IsoSymlink));
if (node == NULL) {
return ISO_MEM_ERROR;
}
node->node.refcount = 1;
node->node.type = LIBISO_SYMLINK;
node->node.name = strdup(name);
if (node->node.name == NULL) {
free(node);
return ISO_MEM_ERROR;
}
node->dest = strdup(dest);
if (node->dest == NULL) {
free(node->node.name);
free(node);
return ISO_MEM_ERROR;
}
/* permissions from parent */
node->node.mode = S_IFLNK | 0777;
node->node.uid = parent->node.uid;
node->node.gid = parent->node.gid;
node->node.hidden = parent->node.hidden;
/* current time */
now = time(NULL);
node->node.atime = now;
node->node.ctime = now;
node->node.mtime = now;
/* add to dir */
node->node.parent = parent;
node->node.next = *pos;
*pos = (IsoNode*)node;
if (link) {
*link = node;
}
return ++parent->nchildren;
}
/**
* Add a new special file to the directory tree. As far as libisofs concerns,
* an special file is a block device, a character device, a FIFO (named pipe)
* or a socket. You can choose the specific kind of file you want to add
* by setting mode propertly (see man 2 stat).
*
* Note that special files are only written to image when Rock Ridge
* extensions are enabled. Moreover, a special file is just a directory entry
* in the image tree, no data is written beyond that.
*
* Owner and hidden atts are taken from parent. You can modify any of them
* later.
*
* @param parent
* the dir where the new special file will be created
* @param name
* name for the new special file. If a node with same name already exists
* on parent, this functions fails with ISO_NODE_NAME_NOT_UNIQUE.
* @param mode
* file type and permissions for the new node. Note that you can't
* specify any kind of file here, only special types are allowed. i.e,
* S_IFSOCK, S_IFBLK, S_IFCHR and S_IFIFO are valid types; S_IFLNK,
* S_IFREG and S_IFDIR aren't.
* @param dev
* device ID, equivalent to the st_rdev field in man 2 stat.
* @param special
* place where to store a pointer to the newly created special file. No
* extra ref is addded, so you will need to call iso_node_ref() if you
* really need it. You can pass NULL in this parameter if you don't need
* the pointer.
* @return
* number of nodes in parent if success, < 0 otherwise
* Possible errors:
* ISO_NULL_POINTER, if parent, name or dest are NULL
* ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
* ISO_MEM_ERROR
*
*/
int iso_tree_add_new_special(IsoDir *parent, const char *name, mode_t mode,
dev_t dev, IsoSpecial **special)
{
IsoSpecial *node;
IsoNode **pos;
time_t now;
if (parent == NULL || name == NULL) {
return ISO_NULL_POINTER;
}
if (S_ISLNK(mode) || S_ISREG(mode) || S_ISDIR(mode)) {
return ISO_WRONG_ARG_VALUE;
}
if (special) {
*special = NULL;
}
/* find place where to insert */
pos = &(parent->children);
while (*pos != NULL && strcmp((*pos)->name, name) < 0) {
pos = &((*pos)->next);
}
if (*pos != NULL && !strcmp((*pos)->name, name)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
node = calloc(1, sizeof(IsoSpecial));
if (node == NULL) {
return ISO_MEM_ERROR;
}
node->node.refcount = 1;
node->node.type = LIBISO_SPECIAL;
node->node.name = strdup(name);
if (node->node.name == NULL) {
free(node);
return ISO_MEM_ERROR;
}
node->node.mode = mode;
node->dev = dev;
/* atts from parent */
node->node.uid = parent->node.uid;
node->node.gid = parent->node.gid;
node->node.hidden = parent->node.hidden;
/* current time */
now = time(NULL);
node->node.atime = now;
node->node.ctime = now;
node->node.mtime = now;
/* add to dir */
node->node.parent = parent;
node->node.next = *pos;
*pos = (IsoNode*)node;
if (special) {
*special = node;
}
return ++parent->nchildren;
}
static
int iso_tree_add_node_builder(IsoDir *parent, IsoFileSource *src,
IsoNodeBuilder *builder, IsoNode **node)
{
int result;
struct stat info;
IsoNode *new;
IsoNode **pos;
char *name;
if (parent == NULL || src == NULL || builder == NULL) {
return ISO_NULL_POINTER;
}
if (node) {
*node = NULL;
}
name = src->get_name(src);
/* find place where to insert */
pos = &(parent->children);
while (*pos != NULL && strcmp((*pos)->name, name) < 0) {
pos = &((*pos)->next);
}
if (*pos != NULL && !strcmp((*pos)->name, name)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
/* get info about source */
result = src->lstat(src, &info);
if (result < 0) {
return result;
}
new = NULL;
switch (info.st_mode & S_IFMT) {
case S_IFREG:
{
/* source is a regular file */
IsoStream *stream;
IsoFile *file;
result = iso_file_source_stream_new(src, &stream);
if (result < 0) {
return result;
}
file = malloc(sizeof(IsoFile));
if (file == NULL) {
iso_stream_unref(stream);
return ISO_MEM_ERROR;
}
file->msblock = 0;
file->sort_weight = 0;
file->stream = stream;
file->node.type = LIBISO_FILE;
new = (IsoNode*) file;
}
break;
case S_IFDIR:
{
/* source is a directory */
new = calloc(1, sizeof(IsoDir));
if (new == NULL) {
return ISO_MEM_ERROR;
}
new->type = LIBISO_DIR;
}
break;
case S_IFLNK:
{
/* source is a symbolic link */
char dest[PATH_MAX];
IsoSymlink *link;
result = src->readlink(src, dest, PATH_MAX);
if (result < 0) {
return result;
}
link = malloc(sizeof(IsoSymlink));
if (link == NULL) {
return ISO_MEM_ERROR;
}
link->dest = strdup(dest);
link->node.type = LIBISO_SYMLINK;
new = (IsoNode*) link;
}
break;
case S_IFSOCK:
case S_IFBLK:
case S_IFCHR:
case S_IFIFO:
{
/* source is an special file */
IsoSpecial *special;
special = malloc(sizeof(IsoSpecial));
if (special == NULL) {
return ISO_MEM_ERROR;
}
special->dev = info.st_rdev;
special->node.type = LIBISO_SPECIAL;
new = (IsoNode*) special;
}
break;
}
/* fill fields */
new->refcount = 1;
new->name = strdup(name);
new->mode = info.st_mode;
new->uid = info.st_uid;
new->gid = info.st_gid;
new->atime = info.st_atime;
new->mtime = info.st_mtime;
new->ctime = info.st_ctime;
new->hidden = 0;
/* finally, add node to parent */
new->parent = parent;
new->next = *pos;
*pos = new;
if (node) {
*node = new;
}
return ++parent->nchildren;
}
int iso_tree_add_node(IsoImage *image, IsoDir *parent, const char *path,
IsoNode **node)
{
int result;
IsoFilesystem *fs;
IsoFileSource *file;
if (image == NULL || parent == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
fs = image->fs;
result = fs->get_by_path(fs, path, &file);
if (result < 0) {
return result;
}
result = iso_tree_add_node_builder(parent, file, image->builder, node);
return result;
}
int iso_tree_path_to_node(IsoImage *image, const char *path, IsoNode **node)
{
int result;
IsoNode *n;
IsoDir *dir;
char *ptr, *brk_info, *component;
if (image == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
/* get the first child at the root of the image that is "/" */
dir = image->root;
n = (IsoNode *)dir;
if (!strcmp(path, "/")) {
if (node) {
*node = n;
}
return ISO_SUCCESS;
}
ptr = strdup(path);
result = 0;
/* get the first component of the path */
component = strtok_r(ptr, "/", &brk_info);
while (component) {
if (n->type != LIBISO_DIR) {
n = NULL;
break;
}
dir = (IsoDir *)n;
result = iso_dir_get_node(dir, component, &n);
if (result != 1) {
n = NULL;
break;
}
component = strtok_r(NULL, "/", &brk_info);
}
free(ptr);
if (node) {
*node = n;
}
return result;
}
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