/* $OpenBSD: o_names.c,v 1.22 2017/01/29 17:49:23 beck Exp $ */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <openssl/opensslconf.h>

#include <openssl/err.h>
#include <openssl/lhash.h>
#include <openssl/objects.h>
#include <openssl/safestack.h>

/* I use the ex_data stuff to manage the identifiers for the obj_name_types
 * that applications may define.  I only really use the free function field.
 */
DECLARE_LHASH_OF(OBJ_NAME);
static LHASH_OF(OBJ_NAME) *names_lh = NULL;
static int names_type_num = OBJ_NAME_TYPE_NUM;

typedef struct name_funcs_st {
        unsigned long (*hash_func)(const char *name);
        int (*cmp_func)(const char *a, const char *b);
        void (*free_func)(const char *, int, const char *);
} NAME_FUNCS;

DECLARE_STACK_OF(NAME_FUNCS)

static STACK_OF(NAME_FUNCS) *name_funcs_stack;

/* The LHASH callbacks now use the raw "void *" prototypes and do per-variable
 * casting in the functions. This prevents function pointer casting without the
 * need for macro-generated wrapper functions. */

/* static unsigned long obj_name_hash(OBJ_NAME *a); */
static unsigned long obj_name_hash(const void *a_void);
/* static int obj_name_cmp(OBJ_NAME *a,OBJ_NAME *b); */
static int obj_name_cmp(const void *a_void, const void *b_void);

static IMPLEMENT_LHASH_HASH_FN(obj_name, OBJ_NAME)
static IMPLEMENT_LHASH_COMP_FN(obj_name, OBJ_NAME)

int
OBJ_NAME_init(void)
{
        if (names_lh != NULL)
                return (1);
        names_lh = lh_OBJ_NAME_new();
        return (names_lh != NULL);
}

int
OBJ_NAME_new_index(unsigned long (*hash_func)(const char *),
    int (*cmp_func)(const char *, const char *),
    void (*free_func)(const char *, int, const char *))
{
        int ret;
        int i;
        NAME_FUNCS *name_funcs;

        if (name_funcs_stack == NULL)
                name_funcs_stack = sk_NAME_FUNCS_new_null();
        if (name_funcs_stack == NULL)
                return (0);

        ret = names_type_num;
        names_type_num++;
        for (i = sk_NAME_FUNCS_num(name_funcs_stack); i < names_type_num; i++) {
                name_funcs = malloc(sizeof(NAME_FUNCS));
                if (!name_funcs) {
                        OBJerror(ERR_R_MALLOC_FAILURE);
                        return (0);
                }
                name_funcs->hash_func = lh_strhash;
                name_funcs->cmp_func = strcmp;
                name_funcs->free_func = NULL;
                if (sk_NAME_FUNCS_push(name_funcs_stack, name_funcs) == 0) {
                        free(name_funcs);
                        OBJerror(ERR_R_MALLOC_FAILURE);
                        return (0);
                }
        }
        name_funcs = sk_NAME_FUNCS_value(name_funcs_stack, ret);
        if (hash_func != NULL)
                name_funcs->hash_func = hash_func;
        if (cmp_func != NULL)
                name_funcs->cmp_func = cmp_func;
        if (free_func != NULL)
                name_funcs->free_func = free_func;
        return (ret);
}

/* static int obj_name_cmp(OBJ_NAME *a, OBJ_NAME *b) */
static int
obj_name_cmp(const void *a_void, const void *b_void)
{
        int ret;
        const OBJ_NAME *a = (const OBJ_NAME *)a_void;
        const OBJ_NAME *b = (const OBJ_NAME *)b_void;

        ret = a->type - b->type;
        if (ret == 0) {
                if ((name_funcs_stack != NULL) &&
                    (sk_NAME_FUNCS_num(name_funcs_stack) > a->type)) {
                        ret = sk_NAME_FUNCS_value(name_funcs_stack,
                            a->type)->cmp_func(a->name, b->name);
                } else
                        ret = strcmp(a->name, b->name);
        }
        return (ret);
}

/* static unsigned long obj_name_hash(OBJ_NAME *a) */
static unsigned long
obj_name_hash(const void *a_void)
{
        unsigned long ret;
        const OBJ_NAME *a = (const OBJ_NAME *)a_void;

        if ((name_funcs_stack != NULL) &&
            (sk_NAME_FUNCS_num(name_funcs_stack) > a->type)) {
                ret = sk_NAME_FUNCS_value(name_funcs_stack,
                    a->type)->hash_func(a->name);
        } else {
                ret = lh_strhash(a->name);
        }
        ret ^= a->type;
        return (ret);
}

const char *
OBJ_NAME_get(const char *name, int type)
{
        OBJ_NAME on, *ret;
        int num = 0, alias;

        if (name == NULL)
                return (NULL);
        if ((names_lh == NULL) && !OBJ_NAME_init())
                return (NULL);

        alias = type&OBJ_NAME_ALIAS;
        type&= ~OBJ_NAME_ALIAS;

        on.name = name;
        on.type = type;

        for (;;) {
                ret = lh_OBJ_NAME_retrieve(names_lh, &on);
                if (ret == NULL)
                        return (NULL);
                if ((ret->alias) && !alias) {
                        if (++num > 10)
                                return (NULL);
                        on.name = ret->data;
                } else {
                        return (ret->data);
                }
        }
}

int
OBJ_NAME_add(const char *name, int type, const char *data)
{
        OBJ_NAME *onp, *ret;
        int alias;

        if ((names_lh == NULL) && !OBJ_NAME_init())
                return (0);

        alias = type & OBJ_NAME_ALIAS;
        type &= ~OBJ_NAME_ALIAS;

        onp = malloc(sizeof(OBJ_NAME));
        if (onp == NULL) {
                /* ERROR */
                return (0);
        }

        onp->name = name;
        onp->alias = alias;
        onp->type = type;
        onp->data = data;

        ret = lh_OBJ_NAME_insert(names_lh, onp);
        if (ret != NULL) {
                /* free things */
                if ((name_funcs_stack != NULL) &&
                    (sk_NAME_FUNCS_num(name_funcs_stack) > ret->type)) {
                        /* XXX: I'm not sure I understand why the free
                         * function should get three arguments...
                         * -- Richard Levitte
                         */
                        sk_NAME_FUNCS_value(
                            name_funcs_stack, ret->type)->free_func(
                            ret->name, ret->type, ret->data);
                }
                free(ret);
        } else {
                if (lh_OBJ_NAME_error(names_lh)) {
                        /* ERROR */
                        return (0);
                }
        }
        return (1);
}

int
OBJ_NAME_remove(const char *name, int type)
{
        OBJ_NAME on, *ret;

        if (names_lh == NULL)
                return (0);

        type &= ~OBJ_NAME_ALIAS;
        on.name = name;
        on.type = type;
        ret = lh_OBJ_NAME_delete(names_lh, &on);
        if (ret != NULL) {
                /* free things */
                if ((name_funcs_stack != NULL) &&
                    (sk_NAME_FUNCS_num(name_funcs_stack) > ret->type)) {
                        /* XXX: I'm not sure I understand why the free
                         * function should get three arguments...
                         * -- Richard Levitte
                         */
                        sk_NAME_FUNCS_value(
                            name_funcs_stack, ret->type)->free_func(
                            ret->name, ret->type, ret->data);
                }
                free(ret);
                return (1);
        } else
                return (0);
}

struct doall {
        int type;
        void (*fn)(const OBJ_NAME *, void *arg);
        void *arg;
};

static void
do_all_fn_doall_arg(const OBJ_NAME *name, struct doall *d)
{
        if (name->type == d->type)
                d->fn(name, d->arg);
}

static IMPLEMENT_LHASH_DOALL_ARG_FN(do_all_fn, const OBJ_NAME, struct doall)

void
OBJ_NAME_do_all(int type, void (*fn)(const OBJ_NAME *, void *arg), void *arg)
{
        struct doall d;

        d.type = type;
        d.fn = fn;
        d.arg = arg;

        lh_OBJ_NAME_doall_arg(names_lh, LHASH_DOALL_ARG_FN(do_all_fn),
            struct doall, &d);
}

struct doall_sorted {
        int type;
        int n;
        const OBJ_NAME **names;
};

static void
do_all_sorted_fn(const OBJ_NAME *name, void *d_)
{
        struct doall_sorted *d = d_;

        if (name->type != d->type)
                return;

        d->names[d->n++] = name;
}

static int
do_all_sorted_cmp(const void *n1_, const void *n2_)
{
        const OBJ_NAME * const *n1 = n1_;
        const OBJ_NAME * const *n2 = n2_;

        return strcmp((*n1)->name, (*n2)->name);
}

void
OBJ_NAME_do_all_sorted(int type, void (*fn)(const OBJ_NAME *, void *arg),
    void *arg)
{
        struct doall_sorted d;
        int n;

        d.type = type;
        d.names = reallocarray(NULL, lh_OBJ_NAME_num_items(names_lh),
            sizeof *d.names);
        d.n = 0;
        if (d.names != NULL) {
                OBJ_NAME_do_all(type, do_all_sorted_fn, &d);

                qsort((void *)d.names, d.n, sizeof *d.names, do_all_sorted_cmp);

                for (n = 0; n < d.n; ++n)
                        fn(d.names[n], arg);

                free(d.names);
        }
}

static int free_type;

static void
names_lh_free_doall(OBJ_NAME *onp)
{
        if (onp == NULL)
                return;

        if (free_type < 0 || free_type == onp->type)
                OBJ_NAME_remove(onp->name, onp->type);
}

static IMPLEMENT_LHASH_DOALL_FN(names_lh_free, OBJ_NAME)

static void
name_funcs_free(NAME_FUNCS *ptr)
{
        free(ptr);
}

void
OBJ_NAME_cleanup(int type)
{
        unsigned long down_load;

        if (names_lh == NULL)
                return;

        free_type = type;
        down_load = lh_OBJ_NAME_down_load(names_lh);
        lh_OBJ_NAME_down_load(names_lh) = 0;

        lh_OBJ_NAME_doall(names_lh, LHASH_DOALL_FN(names_lh_free));
        if (type < 0) {
                lh_OBJ_NAME_free(names_lh);
                sk_NAME_FUNCS_pop_free(name_funcs_stack, name_funcs_free);
                names_lh = NULL;
                name_funcs_stack = NULL;
        } else
                lh_OBJ_NAME_down_load(names_lh) = down_load;
}