libisofs/src/tree.c
2007-12-06 02:43:24 +01:00

283 lines
8.2 KiB
C

/*
* 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 <stdlib.h>
#include <string.h>
#include <time.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;
}
/* 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)->next;
*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;
}
/* 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)->next;
*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 (mode & (S_IFLNK | S_IFREG | S_IFDIR)) {
return ISO_WRONG_ARG_VALUE;
}
/* 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)->next;
*pos = (IsoNode*)node;
if (special) {
*special = node;
}
return ++parent->nchildren;
}