// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
 */

#include "dtc.h"
#include "srcpos.h"

/*
 * Tree building functions
 */

void add_label(struct label **labels, char *label)
{
        struct label *new;

        /* Make sure the label isn't already there */
        for_each_label_withdel(*labels, new)
                if (streq(new->label, label)) {
                        new->deleted = 0;
                        return;
                }

        new = xmalloc(sizeof(*new));
        memset(new, 0, sizeof(*new));
        new->label = label;
        new->next = *labels;
        *labels = new;
}

void delete_labels(struct label **labels)
{
        struct label *label;

        for_each_label(*labels, label)
                label->deleted = 1;
}

struct property *build_property(char *name, struct data val,
                                struct srcpos *srcpos)
{
        struct property *new = xmalloc(sizeof(*new));

        memset(new, 0, sizeof(*new));

        new->name = name;
        new->val = val;
        new->srcpos = srcpos_copy(srcpos);

        return new;
}

struct property *build_property_delete(char *name)
{
        struct property *new = xmalloc(sizeof(*new));

        memset(new, 0, sizeof(*new));

        new->name = name;
        new->deleted = 1;

        return new;
}

struct property *chain_property(struct property *first, struct property *list)
{
        assert(first->next == NULL);

        first->next = list;
        return first;
}

struct property *reverse_properties(struct property *first)
{
        struct property *p = first;
        struct property *head = NULL;
        struct property *next;

        while (p) {
                next = p->next;
                p->next = head;
                head = p;
                p = next;
        }
        return head;
}

struct node *build_node(struct property *proplist, struct node *children,
                        struct srcpos *srcpos)
{
        struct node *new = xmalloc(sizeof(*new));
        struct node *child;

        memset(new, 0, sizeof(*new));

        new->proplist = reverse_properties(proplist);
        new->children = children;
        new->srcpos = srcpos_copy(srcpos);

        for_each_child(new, child) {
                child->parent = new;
        }

        return new;
}

struct node *build_node_delete(struct srcpos *srcpos)
{
        struct node *new = xmalloc(sizeof(*new));

        memset(new, 0, sizeof(*new));

        new->deleted = 1;
        new->srcpos = srcpos_copy(srcpos);

        return new;
}

struct node *name_node(struct node *node, char *name)
{
        assert(node->name == NULL);

        node->name = name;

        return node;
}

struct node *omit_node_if_unused(struct node *node)
{
        node->omit_if_unused = 1;

        return node;
}

struct node *reference_node(struct node *node)
{
        node->is_referenced = 1;

        return node;
}

struct node *merge_nodes(struct node *old_node, struct node *new_node)
{
        struct property *new_prop, *old_prop;
        struct node *new_child, *old_child;
        struct label *l;

        old_node->deleted = 0;

        /* Add new node labels to old node */
        for_each_label_withdel(new_node->labels, l)
                add_label(&old_node->labels, l->label);

        /* Move properties from the new node to the old node.  If there
         * is a collision, replace the old value with the new */
        while (new_node->proplist) {
                /* Pop the property off the list */
                new_prop = new_node->proplist;
                new_node->proplist = new_prop->next;
                new_prop->next = NULL;

                if (new_prop->deleted) {
                        delete_property_by_name(old_node, new_prop->name);
                        free(new_prop);
                        continue;
                }

                /* Look for a collision, set new value if there is */
                for_each_property_withdel(old_node, old_prop) {
                        if (streq(old_prop->name, new_prop->name)) {
                                /* Add new labels to old property */
                                for_each_label_withdel(new_prop->labels, l)
                                        add_label(&old_prop->labels, l->label);

                                old_prop->val = new_prop->val;
                                old_prop->deleted = 0;
                                free(old_prop->srcpos);
                                old_prop->srcpos = new_prop->srcpos;
                                free(new_prop);
                                new_prop = NULL;
                                break;
                        }
                }

                /* if no collision occurred, add property to the old node. */
                if (new_prop)
                        add_property(old_node, new_prop);
        }

        /* Move the override child nodes into the primary node.  If
         * there is a collision, then merge the nodes. */
        while (new_node->children) {
                /* Pop the child node off the list */
                new_child = new_node->children;
                new_node->children = new_child->next_sibling;
                new_child->parent = NULL;
                new_child->next_sibling = NULL;

                if (new_child->deleted) {
                        delete_node_by_name(old_node, new_child->name);
                        free(new_child);
                        continue;
                }

                /* Search for a collision.  Merge if there is */
                for_each_child_withdel(old_node, old_child) {
                        if (streq(old_child->name, new_child->name)) {
                                merge_nodes(old_child, new_child);
                                new_child = NULL;
                                break;
                        }
                }

                /* if no collision occurred, add child to the old node. */
                if (new_child)
                        add_child(old_node, new_child);
        }

        old_node->srcpos = srcpos_extend(old_node->srcpos, new_node->srcpos);

        /* The new node contents are now merged into the old node.  Free
         * the new node. */
        free(new_node);

        return old_node;
}

struct node * add_orphan_node(struct node *dt, struct node *new_node, char *ref)
{
        static unsigned int next_orphan_fragment = 0;
        struct node *node;
        struct property *p;
        struct data d = empty_data;
        char *name;

        if (ref[0] == '/') {
                d = data_add_marker(d, TYPE_STRING, ref);
                d = data_append_data(d, ref, strlen(ref) + 1);

                p = build_property("target-path", d, NULL);
        } else {
                d = data_add_marker(d, REF_PHANDLE, ref);
                d = data_append_integer(d, 0xffffffff, 32);

                p = build_property("target", d, NULL);
        }

        xasprintf(&name, "fragment@%u",
                        next_orphan_fragment++);
        name_node(new_node, "__overlay__");
        node = build_node(p, new_node, NULL);
        name_node(node, name);

        add_child(dt, node);
        return dt;
}

struct node *chain_node(struct node *first, struct node *list)
{
        assert(first->next_sibling == NULL);

        first->next_sibling = list;
        return first;
}

void add_property(struct node *node, struct property *prop)
{
        struct property **p;

        prop->next = NULL;

        p = &node->proplist;
        while (*p)
                p = &((*p)->next);

        *p = prop;
}

void delete_property_by_name(struct node *node, char *name)
{
        struct property *prop = node->proplist;

        while (prop) {
                if (streq(prop->name, name)) {
                        delete_property(prop);
                        return;
                }
                prop = prop->next;
        }
}

void delete_property(struct property *prop)
{
        prop->deleted = 1;
        delete_labels(&prop->labels);
}

void add_child(struct node *parent, struct node *child)
{
        struct node **p;

        child->next_sibling = NULL;
        child->parent = parent;

        p = &parent->children;
        while (*p)
                p = &((*p)->next_sibling);

        *p = child;
}

void delete_node_by_name(struct node *parent, char *name)
{
        struct node *node = parent->children;

        while (node) {
                if (streq(node->name, name)) {
                        delete_node(node);
                        return;
                }
                node = node->next_sibling;
        }
}

void delete_node(struct node *node)
{
        struct property *prop;
        struct node *child;

        node->deleted = 1;
        for_each_child(node, child)
                delete_node(child);
        for_each_property(node, prop)
                delete_property(prop);
        delete_labels(&node->labels);
}

void append_to_property(struct node *node,
                        char *name, const void *data, int len,
                        enum markertype type)
{
        struct data d;
        struct property *p;

        p = get_property(node, name);
        if (p) {
                d = data_add_marker(p->val, type, name);
                d = data_append_data(d, data, len);
                p->val = d;
        } else {
                d = data_add_marker(empty_data, type, name);
                d = data_append_data(d, data, len);
                p = build_property(name, d, NULL);
                add_property(node, p);
        }
}

struct reserve_info *build_reserve_entry(uint64_t address, uint64_t size)
{
        struct reserve_info *new = xmalloc(sizeof(*new));

        memset(new, 0, sizeof(*new));

        new->address = address;
        new->size = size;

        return new;
}

struct reserve_info *chain_reserve_entry(struct reserve_info *first,
                                        struct reserve_info *list)
{
        assert(first->next == NULL);

        first->next = list;
        return first;
}

struct reserve_info *add_reserve_entry(struct reserve_info *list,
                                      struct reserve_info *new)
{
        struct reserve_info *last;

        new->next = NULL;

        if (! list)
                return new;

        for (last = list; last->next; last = last->next)
                ;

        last->next = new;

        return list;
}

struct dt_info *build_dt_info(unsigned int dtsflags,
                              struct reserve_info *reservelist,
                              struct node *tree, uint32_t boot_cpuid_phys)
{
        struct dt_info *dti;

        dti = xmalloc(sizeof(*dti));
        dti->dtsflags = dtsflags;
        dti->reservelist = reservelist;
        dti->dt = tree;
        dti->boot_cpuid_phys = boot_cpuid_phys;

        return dti;
}

/*
 * Tree accessor functions
 */

const char *get_unitname(struct node *node)
{
        if (node->name[node->basenamelen] == '\0')
                return "";
        else
                return node->name + node->basenamelen + 1;
}

struct property *get_property(struct node *node, const char *propname)
{
        struct property *prop;

        for_each_property(node, prop)
                if (streq(prop->name, propname))
                        return prop;

        return NULL;
}

cell_t propval_cell(struct property *prop)
{
        assert(prop->val.len == sizeof(cell_t));
        return fdt32_to_cpu(*((fdt32_t *)prop->val.val));
}

cell_t propval_cell_n(struct property *prop, int n)
{
        assert(prop->val.len / sizeof(cell_t) >= n);
        return fdt32_to_cpu(*((fdt32_t *)prop->val.val + n));
}

struct property *get_property_by_label(struct node *tree, const char *label,
                                       struct node **node)
{
        struct property *prop;
        struct node *c;

        *node = tree;

        for_each_property(tree, prop) {
                struct label *l;

                for_each_label(prop->labels, l)
                        if (streq(l->label, label))
                                return prop;
        }

        for_each_child(tree, c) {
                prop = get_property_by_label(c, label, node);
                if (prop)
                        return prop;
        }

        *node = NULL;
        return NULL;
}

struct marker *get_marker_label(struct node *tree, const char *label,
                                struct node **node, struct property **prop)
{
        struct marker *m;
        struct property *p;
        struct node *c;

        *node = tree;

        for_each_property(tree, p) {
                *prop = p;
                m = p->val.markers;
                for_each_marker_of_type(m, LABEL)
                        if (streq(m->ref, label))
                                return m;
        }

        for_each_child(tree, c) {
                m = get_marker_label(c, label, node, prop);
                if (m)
                        return m;
        }

        *prop = NULL;
        *node = NULL;
        return NULL;
}

struct node *get_subnode(struct node *node, const char *nodename)
{
        struct node *child;

        for_each_child(node, child)
                if (streq(child->name, nodename))
                        return child;

        return NULL;
}

struct node *get_node_by_path(struct node *tree, const char *path)
{
        const char *p;
        struct node *child;

        if (!path || ! (*path)) {
                if (tree->deleted)
                        return NULL;
                return tree;
        }

        while (path[0] == '/')
                path++;

        p = strchr(path, '/');

        for_each_child(tree, child) {
                if (p && (strlen(child->name) == p-path) &&
                    strprefixeq(path, p - path, child->name))
                        return get_node_by_path(child, p+1);
                else if (!p && streq(path, child->name))
                        return child;
        }

        return NULL;
}

struct node *get_node_by_label(struct node *tree, const char *label)
{
        struct node *child, *node;
        struct label *l;

        assert(label && (strlen(label) > 0));

        for_each_label(tree->labels, l)
                if (streq(l->label, label))
                        return tree;

        for_each_child(tree, child) {
                node = get_node_by_label(child, label);
                if (node)
                        return node;
        }

        return NULL;
}

struct node *get_node_by_phandle(struct node *tree, cell_t phandle)
{
        struct node *child, *node;

        if ((phandle == 0) || (phandle == -1)) {
                assert(generate_fixups);
                return NULL;
        }

        if (tree->phandle == phandle) {
                if (tree->deleted)
                        return NULL;
                return tree;
        }

        for_each_child(tree, child) {
                node = get_node_by_phandle(child, phandle);
                if (node)
                        return node;
        }

        return NULL;
}

struct node *get_node_by_ref(struct node *tree, const char *ref)
{
        if (streq(ref, "/"))
                return tree;
        else if (ref[0] == '/')
                return get_node_by_path(tree, ref);
        else
                return get_node_by_label(tree, ref);
}

cell_t get_node_phandle(struct node *root, struct node *node)
{
        static cell_t phandle = 1; /* FIXME: ick, static local */
        struct data d = empty_data;

        if ((node->phandle != 0) && (node->phandle != -1))
                return node->phandle;

        while (get_node_by_phandle(root, phandle))
                phandle++;

        node->phandle = phandle;

        d = data_add_marker(d, TYPE_UINT32, NULL);
        d = data_append_cell(d, phandle);

        if (!get_property(node, "linux,phandle")
            && (phandle_format & PHANDLE_LEGACY))
                add_property(node, build_property("linux,phandle", d, NULL));

        if (!get_property(node, "phandle")
            && (phandle_format & PHANDLE_EPAPR))
                add_property(node, build_property("phandle", d, NULL));

        /* If the node *does* have a phandle property, we must
         * be dealing with a self-referencing phandle, which will be
         * fixed up momentarily in the caller */

        return node->phandle;
}

uint32_t guess_boot_cpuid(struct node *tree)
{
        struct node *cpus, *bootcpu;
        struct property *reg;

        cpus = get_node_by_path(tree, "/cpus");
        if (!cpus)
                return 0;


        bootcpu = cpus->children;
        if (!bootcpu)
                return 0;

        reg = get_property(bootcpu, "reg");
        if (!reg || (reg->val.len != sizeof(uint32_t)))
                return 0;

        /* FIXME: Sanity check node? */

        return propval_cell(reg);
}

static int cmp_reserve_info(const void *ax, const void *bx)
{
        const struct reserve_info *a, *b;

        a = *((const struct reserve_info * const *)ax);
        b = *((const struct reserve_info * const *)bx);

        if (a->address < b->address)
                return -1;
        else if (a->address > b->address)
                return 1;
        else if (a->size < b->size)
                return -1;
        else if (a->size > b->size)
                return 1;
        else
                return 0;
}

static void sort_reserve_entries(struct dt_info *dti)
{
        struct reserve_info *ri, **tbl;
        int n = 0, i = 0;

        for (ri = dti->reservelist;
             ri;
             ri = ri->next)
                n++;

        if (n == 0)
                return;

        tbl = xmalloc(n * sizeof(*tbl));

        for (ri = dti->reservelist;
             ri;
             ri = ri->next)
                tbl[i++] = ri;

        qsort(tbl, n, sizeof(*tbl), cmp_reserve_info);

        dti->reservelist = tbl[0];
        for (i = 0; i < (n-1); i++)
                tbl[i]->next = tbl[i+1];
        tbl[n-1]->next = NULL;

        free(tbl);
}

static int cmp_prop(const void *ax, const void *bx)
{
        const struct property *a, *b;

        a = *((const struct property * const *)ax);
        b = *((const struct property * const *)bx);

        return strcmp(a->name, b->name);
}

static void sort_properties(struct node *node)
{
        int n = 0, i = 0;
        struct property *prop, **tbl;

        for_each_property_withdel(node, prop)
                n++;

        if (n == 0)
                return;

        tbl = xmalloc(n * sizeof(*tbl));

        for_each_property_withdel(node, prop)
                tbl[i++] = prop;

        qsort(tbl, n, sizeof(*tbl), cmp_prop);

        node->proplist = tbl[0];
        for (i = 0; i < (n-1); i++)
                tbl[i]->next = tbl[i+1];
        tbl[n-1]->next = NULL;

        free(tbl);
}

static int cmp_subnode(const void *ax, const void *bx)
{
        const struct node *a, *b;

        a = *((const struct node * const *)ax);
        b = *((const struct node * const *)bx);

        return strcmp(a->name, b->name);
}

static void sort_subnodes(struct node *node)
{
        int n = 0, i = 0;
        struct node *subnode, **tbl;

        for_each_child_withdel(node, subnode)
                n++;

        if (n == 0)
                return;

        tbl = xmalloc(n * sizeof(*tbl));

        for_each_child_withdel(node, subnode)
                tbl[i++] = subnode;

        qsort(tbl, n, sizeof(*tbl), cmp_subnode);

        node->children = tbl[0];
        for (i = 0; i < (n-1); i++)
                tbl[i]->next_sibling = tbl[i+1];
        tbl[n-1]->next_sibling = NULL;

        free(tbl);
}

static void sort_node(struct node *node)
{
        struct node *c;

        sort_properties(node);
        sort_subnodes(node);
        for_each_child_withdel(node, c)
                sort_node(c);
}

void sort_tree(struct dt_info *dti)
{
        sort_reserve_entries(dti);
        sort_node(dti->dt);
}

/* utility helper to avoid code duplication */
static struct node *build_and_name_child_node(struct node *parent, char *name)
{
        struct node *node;

        node = build_node(NULL, NULL, NULL);
        name_node(node, xstrdup(name));
        add_child(parent, node);

        return node;
}

static struct node *build_root_node(struct node *dt, char *name)
{
        struct node *an;

        an = get_subnode(dt, name);
        if (!an)
                an = build_and_name_child_node(dt, name);

        if (!an)
                die("Could not build root node /%s\n", name);

        return an;
}

static bool any_label_tree(struct dt_info *dti, struct node *node)
{
        struct node *c;

        if (node->labels)
                return true;

        for_each_child(node, c)
                if (any_label_tree(dti, c))
                        return true;

        return false;
}

static void generate_label_tree_internal(struct dt_info *dti,
                                         struct node *an, struct node *node,
                                         bool allocph)
{
        struct node *dt = dti->dt;
        struct node *c;
        struct property *p;
        struct label *l;

        /* if there are labels */
        if (node->labels) {

                /* now add the label in the node */
                for_each_label(node->labels, l) {

                        /* check whether the label already exists */
                        p = get_property(an, l->label);
                        if (p) {
                                fprintf(stderr, "WARNING: label %s already"
                                        " exists in /%s", l->label,
                                        an->name);
                                continue;
                        }

                        /* insert it */
                        p = build_property(l->label,
                                data_copy_escape_string(node->fullpath,
                                                strlen(node->fullpath)),
                                NULL);
                        add_property(an, p);
                }

                /* force allocation of a phandle for this node */
                if (allocph)
                        (void)get_node_phandle(dt, node);
        }

        for_each_child(node, c)
                generate_label_tree_internal(dti, an, c, allocph);
}

static bool any_fixup_tree(struct dt_info *dti, struct node *node)
{
        struct node *c;
        struct property *prop;
        struct marker *m;

        for_each_property(node, prop) {
                m = prop->val.markers;
                for_each_marker_of_type(m, REF_PHANDLE) {
                        if (!get_node_by_ref(dti->dt, m->ref))
                                return true;
                }
        }

        for_each_child(node, c) {
                if (any_fixup_tree(dti, c))
                        return true;
        }

        return false;
}

static void add_fixup_entry(struct dt_info *dti, struct node *fn,
                            struct node *node, struct property *prop,
                            struct marker *m)
{
        char *entry;

        /* m->ref can only be a REF_PHANDLE, but check anyway */
        assert(m->type == REF_PHANDLE);

        /* there shouldn't be any ':' in the arguments */
        if (strchr(node->fullpath, ':') || strchr(prop->name, ':'))
                die("arguments should not contain ':'\n");

        xasprintf(&entry, "%s:%s:%u",
                        node->fullpath, prop->name, m->offset);
        append_to_property(fn, m->ref, entry, strlen(entry) + 1, TYPE_STRING);

        free(entry);
}

static void generate_fixups_tree_internal(struct dt_info *dti,
                                          struct node *fn,
                                          struct node *node)
{
        struct node *dt = dti->dt;
        struct node *c;
        struct property *prop;
        struct marker *m;
        struct node *refnode;

        for_each_property(node, prop) {
                m = prop->val.markers;
                for_each_marker_of_type(m, REF_PHANDLE) {
                        refnode = get_node_by_ref(dt, m->ref);
                        if (!refnode)
                                add_fixup_entry(dti, fn, node, prop, m);
                }
        }

        for_each_child(node, c)
                generate_fixups_tree_internal(dti, fn, c);
}

static bool any_local_fixup_tree(struct dt_info *dti, struct node *node)
{
        struct node *c;
        struct property *prop;
        struct marker *m;

        for_each_property(node, prop) {
                m = prop->val.markers;
                for_each_marker_of_type(m, REF_PHANDLE) {
                        if (get_node_by_ref(dti->dt, m->ref))
                                return true;
                }
        }

        for_each_child(node, c) {
                if (any_local_fixup_tree(dti, c))
                        return true;
        }

        return false;
}

static void add_local_fixup_entry(struct dt_info *dti,
                struct node *lfn, struct node *node,
                struct property *prop, struct marker *m,
                struct node *refnode)
{
        struct node *wn, *nwn;  /* local fixup node, walk node, new */
        fdt32_t value_32;
        char **compp;
        int i, depth;

        /* walk back retrieving depth */
        depth = 0;
        for (wn = node; wn; wn = wn->parent)
                depth++;

        /* allocate name array */
        compp = xmalloc(sizeof(*compp) * depth);

        /* store names in the array */
        for (wn = node, i = depth - 1; wn; wn = wn->parent, i--)
                compp[i] = wn->name;

        /* walk the path components creating nodes if they don't exist */
        for (wn = lfn, i = 1; i < depth; i++, wn = nwn) {
                /* if no node exists, create it */
                nwn = get_subnode(wn, compp[i]);
                if (!nwn)
                        nwn = build_and_name_child_node(wn, compp[i]);
        }

        free(compp);

        value_32 = cpu_to_fdt32(m->offset);
        append_to_property(wn, prop->name, &value_32, sizeof(value_32), TYPE_UINT32);
}

static void generate_local_fixups_tree_internal(struct dt_info *dti,
                                                struct node *lfn,
                                                struct node *node)
{
        struct node *dt = dti->dt;
        struct node *c;
        struct property *prop;
        struct marker *m;
        struct node *refnode;

        for_each_property(node, prop) {
                m = prop->val.markers;
                for_each_marker_of_type(m, REF_PHANDLE) {

                        refnode = get_node_by_ref(dt, m->ref);
                        if (refnode)
                                add_local_fixup_entry(dti, lfn, node, prop, m, refnode);
                }
        }

        for_each_child(node, c)
                generate_local_fixups_tree_internal(dti, lfn, c);
}

void generate_label_tree(struct dt_info *dti, char *name, bool allocph)
{
        if (!any_label_tree(dti, dti->dt))
                return;
        generate_label_tree_internal(dti, build_root_node(dti->dt, name),
                                     dti->dt, allocph);
}

void generate_fixups_tree(struct dt_info *dti, char *name)
{
        if (!any_fixup_tree(dti, dti->dt))
                return;
        generate_fixups_tree_internal(dti, build_root_node(dti->dt, name),
                                      dti->dt);
}

void generate_local_fixups_tree(struct dt_info *dti, char *name)
{
        if (!any_local_fixup_tree(dti, dti->dt))
                return;
        generate_local_fixups_tree_internal(dti, build_root_node(dti->dt, name),
                                            dti->dt);
}