/* MSPDebug - debugging tool for the eZ430
 * Copyright (C) 2009, 2010 Daniel Beer
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <sys/types.h>
#include <regex.h>
#include "stab.h"
#include "btree.h"

struct sym_key {
	char name[64];
};

static const struct sym_key sym_key_zero;

static int sym_key_compare(const void *left, const void *right)
{
	return strcmp(((const struct sym_key *)left)->name,
		      ((const struct sym_key *)right)->name);
}

static void sym_key_init(struct sym_key *key, const char *text)
{
	int len = strlen(text);

	if (len >= sizeof(key->name))
		len = sizeof(key->name) - 1;

	memcpy(key->name, text, len);
	key->name[len] = 0;
}

struct addr_key {
	u_int16_t       addr;
	char            name[64];
};

static const struct addr_key addr_key_zero;

static int addr_key_compare(const void *left, const void *right)
{
	const struct addr_key *kl = (const struct addr_key *)left;
	const struct addr_key *kr = (const struct addr_key *)right;

	if (kl->addr < kr->addr)
		return -1;
	if (kl->addr > kr->addr)
		return 1;

	return strcmp(kl->name, kr->name);
}

static void addr_key_init(struct addr_key *key, u_int16_t addr,
			  const char *text)
{
	int len = strlen(text);

	if (len >= sizeof(key->name))
		len = sizeof(key->name) - 1;

	key->addr = addr;
	memcpy(key->name, text, len);
	key->name[len] = 0;
}

static const struct btree_def sym_table_def = {
	.compare = sym_key_compare,
	.zero = &sym_key_zero,
	.branches = 32,
	.key_size = sizeof(struct sym_key),
	.data_size = sizeof(u_int16_t)
};

static const struct btree_def addr_table_def = {
	.compare = addr_key_compare,
	.zero = &addr_key_zero,
	.branches = 32,
	.key_size = sizeof(struct addr_key),
	.data_size = 0
};

static btree_t sym_table;
static btree_t addr_table;

/************************************************************************
 * Public interface
 */

int stab_init(void)
{
	sym_table = btree_alloc(&sym_table_def);
	if (!sym_table) {
		fprintf(stderr, "stab: failed to allocate symbol table\n");
		return -1;
	}

	addr_table = btree_alloc(&addr_table_def);
	if (!addr_table) {
		fprintf(stderr, "stab: failed to allocate address table\n");
		btree_free(sym_table);
		return -1;
	}

	return 0;
}

void stab_exit(void)
{
	btree_free(sym_table);
	btree_free(addr_table);
}

void stab_clear(void)
{
	btree_clear(sym_table);
	btree_clear(addr_table);
}

int stab_set(const char *name, u_int16_t addr)
{
	struct sym_key skey;
	struct addr_key akey;
	u_int16_t old_addr;

	sym_key_init(&skey, name);

	/* Look for an old address first, and delete the reverse mapping
	 * if it's there.
	 */
	if (!btree_get(sym_table, &skey, &old_addr)) {
		addr_key_init(&akey, old_addr, skey.name);
		btree_delete(addr_table, &akey);
	}

	/* Put the new mapping into both tables */
	addr_key_init(&akey, addr, name);
	if (btree_put(addr_table, &akey, NULL) < 0 ||
	    btree_put(sym_table, &skey, &addr) < 0) {
		fprintf(stderr, "stab: can't set %s = 0x%04x\n", name, addr);
		return -1;
	}

	return 0;
}

int stab_get(const char *name, u_int16_t *value)
{
	struct sym_key skey;

	sym_key_init(&skey, name);
	if (btree_get(sym_table, &skey, value)) {
		fprintf(stderr, "stab: can't find symbol: %s\n", name);
		return -1;
	}

	return 0;
}

int stab_del(const char *name)
{
	struct sym_key skey;
	u_int16_t value;
	struct addr_key akey;

	sym_key_init(&skey, name);
	if (btree_get(sym_table, &skey, &value)) {
		fprintf(stderr, "stab: can't delete nonexistent symbol: %s\n",
			name);
		return -1;
	}

	addr_key_init(&akey, value, name);
	btree_delete(sym_table, &skey);
	btree_delete(addr_table, &akey);

	return 0;
}

int stab_enum(stab_callback_t cb)
{
	struct sym_key skey;
	u_int16_t value;
	int ret;
	int count = 0;

	ret = btree_select(sym_table, NULL, BTREE_FIRST, &skey, &value);
	while (!ret) {
		if (cb && cb(skey.name, value) < 0)
			return -1;
		count++;
		ret = btree_select(sym_table, NULL, BTREE_NEXT, &skey, &value);
	}

	return count;
}

int stab_re_search(const char *regex, stab_callback_t cb)
{
	struct sym_key skey;
	u_int16_t value;
	int ret;
	int count = 0;
	regex_t preg;

	if (regcomp(&preg, regex, REG_EXTENDED | REG_NOSUB)) {
		fprintf(stderr, "stab: failed to compile: %s\n", regex);
		return -1;
	}

	ret = btree_select(sym_table, NULL, BTREE_FIRST, &skey, &value);
	while (!ret) {
		if (!regexec(&preg, skey.name, 0, NULL, 0)) {
			if (cb && cb(skey.name, value) < 0) {
				regfree(&preg);
				return -1;
			}

			count++;
		}

		ret = btree_select(sym_table, NULL, BTREE_NEXT, &skey, &value);
	}

	regfree(&preg);
	return count;
}

static char token_buf[64];
static int token_len;
static int token_mult;
static int token_sum;

static int token_add(void)
{
	int i;
	struct sym_key skey;
	u_int16_t value;

	if (!token_len)
		return 0;

	token_buf[token_len] = 0;
	token_len = 0;

	/* Is it a decimal? */
	i = 0;
	while (token_buf[i] && isdigit(token_buf[i]))
		i++;
	if (!token_buf[i]) {
		token_sum += token_mult * atoi(token_buf);
		return 0;
	}

	/* Is it hex? */
	if (token_buf[0] == '0' && tolower(token_buf[1]) == 'x') {
		token_sum += token_mult * strtol(token_buf + 2, NULL, 16);
		return 0;
	}

	/* Look up the name in the symbol table */
	sym_key_init(&skey, token_buf);
	if (!btree_get(sym_table, &skey, &value)) {
		token_sum += token_mult * (int)value;
		return 0;
	}

	fprintf(stderr, "stab: unknown token: %s\n", token_buf);
	return -1;
}

int stab_parse(const char *text, int *addr)
{
	token_len = 0;
	token_mult = 1;
	token_sum = 0;

	while (*text) {
		if (isalnum(*text) || *text == '_' || *text == '$') {
			if (token_len + 1 < sizeof(token_buf))
				token_buf[token_len++] = *text;
		} else {
			if (token_add() < 0)
				return -1;
			if (*text == '+')
				token_mult = 1;
			if (*text == '-')
				token_mult = -1;
		}

		text++;
	}

	if (token_add() < 0)
		return -1;

	*addr = token_sum & 0xffff;
	return 0;
}

int stab_nearest(u_int16_t addr, char *ret_name, int max_len,
		 u_int16_t *ret_offset)
{
	struct addr_key akey;
	int i;

	akey.addr = addr;
	for (i = 0; i < sizeof(akey.name); i++)
		akey.name[i] = 0xff;
	akey.name[sizeof(akey.name) - 1] = 0xff;

	if (!btree_select(addr_table, &akey, BTREE_LE, &akey, NULL)) {
		strncpy(ret_name, akey.name, max_len);
		ret_name[max_len - 1] = 0;
		*ret_offset = addr - akey.addr;
		return 0;
	}

	return -1;
}