/* 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 <errno.h>
#include "stab.h"
#include "binfile.h"
#include "util.h"
#include "parse.h"

static int cmd_eval(char **arg)
{
	int addr;
	u_int16_t offset;
	char name[64];

	if (addr_exp(*arg, &addr) < 0) {
		fprintf(stderr, "=: can't parse: %s\n", *arg);
		return -1;
	}

	printf("0x%04x", addr);
	if (!stab_nearest(addr, name, sizeof(name), &offset)) {
		printf(" = %s", name);
		if (offset)
			printf("+0x%x", offset);
	}
	printf("\n");

	return 0;
}

static struct command command_eval = {
	.name = "=",
	.func = cmd_eval,
	.help =
	"= <expression>\n"
	"    Evaluate an expression using the symbol table.\n"
};

static int cmd_sym_load_add(int clear, char **arg)
{
	FILE *in;
	int result = 0;

	if (clear && modify_prompt(MODIFY_SYMS))
		return 0;

	in = fopen(*arg, "r");
	if (!in) {
		fprintf(stderr, "sym: %s: %s\n", *arg, strerror(errno));
		return -1;
	}

	if (clear)
		stab_clear();

	if (elf32_check(in))
		result = elf32_syms(in, stab_set);
	else if (symmap_check(in))
		result = symmap_syms(in, stab_set);
	else
		fprintf(stderr, "sym: %s: unknown file type\n", *arg);

	fclose(in);

	if (clear)
		modify_clear(MODIFY_SYMS);
	else
		modify_set(MODIFY_SYMS);

	return result;
}

static FILE *savemap_out;

static int savemap_cb(const char *name, u_int16_t value)
{
	if (fprintf(savemap_out, "%04x t %s\n", value, name) < 0) {
		perror("sym: can't write to file");
		return -1;
	}

	return 0;
}

static int cmd_sym_savemap(char **arg)
{
	char *fname = get_arg(arg);

	if (!fname) {
		fprintf(stderr, "sym: filename required to save map\n");
		return -1;
	}

	savemap_out = fopen(fname, "w");
	if (!savemap_out) {
		fprintf(stderr, "sym: couldn't write to %s: %s\n", fname,
			strerror(errno));
		return -1;
	}

	if (stab_enum(savemap_cb) < 0) {
		fclose(savemap_out);
		return -1;
	}

	if (fclose(savemap_out) < 0) {
		fprintf(stderr, "sym: error on close: %s\n", strerror(errno));
		return -1;
	}

	modify_clear(MODIFY_SYMS);
	return 0;
}

static int print_sym(const char *name, u_int16_t value)
{
	printf("0x%04x: %s\n", value, name);
	return 0;
}

static regex_t find_preg;

static int find_sym(const char *name, u_int16_t value)
{
	if (!regexec(&find_preg, name, 0, NULL, 0))
		printf("0x%04x: %s\n", value, name);

	return 0;
}

static int cmd_sym_find(char **arg)
{
	char *expr = get_arg(arg);

	if (!expr) {
		stab_enum(print_sym);
		return 0;
	}

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

	stab_enum(find_sym);
	regfree(&find_preg);
	return 0;
}

struct rename_record {
	char    old_name[64];
	int     start, end;
};

struct rename_record *renames;
static int renames_cap;
static int renames_len;

static void renames_free(void)
{
	if (!renames)
		return;

	free(renames);
	renames = NULL;
	renames_cap = 0;
	renames_len = 0;
}

static int renames_push(const char *old_name,
			int start, int end)
{
	struct rename_record *r;

	if (renames_len + 1 > renames_cap) {
		int new_cap = renames_cap * 2;
		struct rename_record *new_array;

		if (!new_cap)
			new_cap = 64;

		new_array = realloc(renames, new_cap * sizeof(renames[0]));
		if (!new_array) {
			perror("sym: can't allocate memory for renaming");
			return -1;
		}

		renames = new_array;
		renames_cap = new_cap;
	}

	r = &renames[renames_len++];
	strncpy(r->old_name, old_name, sizeof(r->old_name));
	r->old_name[sizeof(r->old_name) - 1] = 0;
	r->start = start;
	r->end = end;

	return 0;
}

static int renames_do(const char *replace)
{
	int i;
	int count = 0;

	for (i = 0; i < renames_len; i++) {
		struct rename_record *r = &renames[i];
		char new_name[128];
		int len = r->start;
		int value;

		if (len + 1 > sizeof(new_name))
			len = sizeof(new_name) - 1;

		memcpy(new_name, r->old_name, len);
		snprintf(new_name + len,
			 sizeof(new_name) - len,
			 "%s%s", replace, r->old_name + r->end);

		printf("%s -> %s\n", r->old_name, new_name);

		if (stab_get(r->old_name, &value) < 0) {
			fprintf(stderr, "sym: warning: "
				"symbol missing: %s\n",
				r->old_name);
		} else {
			stab_del(r->old_name);
			if (stab_set(new_name, value) < 0) {
				fprintf(stderr, "sym: warning: "
					"failed to set new name: %s\n",
					new_name);
			}
		}

		count++;
	}

	if (count)
		modify_set(MODIFY_SYMS);

	printf("%d symbols renamed\n", count);
	return 0;
}

static int find_renames(const char *name, u_int16_t value)
{
	regmatch_t pmatch;

	if (!regexec(&find_preg, name, 1, &pmatch, 0) &&
	    pmatch.rm_so >= 0 && pmatch.rm_eo > pmatch.rm_so)
		return renames_push(name, pmatch.rm_so, pmatch.rm_eo);

	return 0;
}

static int cmd_sym_rename(char **arg)
{
	const char *expr = get_arg(arg);
	const char *replace = get_arg(arg);
	int ret;

	if (!(expr && replace)) {
		fprintf(stderr, "sym: expected pattern and replacement\n");
		return -1;
	}

	if (regcomp(&find_preg, expr, REG_EXTENDED)) {
		fprintf(stderr, "sym: failed to compile: %s\n", expr);
		return -1;
	}

	if (stab_enum(find_renames) < 0) {
		fprintf(stderr, "sym: rename failed\n");
		regfree(&find_preg);
		renames_free();
		return -1;
	}

	regfree(&find_preg);
	ret = renames_do(replace);
	renames_free();
	return ret;
}

static int cmd_sym_del(char **arg)
{
	char *name = get_arg(arg);

	if (!name) {
		fprintf(stderr, "sym: need a name to delete "
			"symbol table entries\n");
		return -1;
	}

	if (stab_del(name) < 0) {
		fprintf(stderr, "sym: can't delete nonexistent symbol: %s\n",
			name);
		return -1;
	}

	modify_set(MODIFY_SYMS);
	return 0;
}

static int cmd_sym(char **arg)
{
	char *subcmd = get_arg(arg);

	if (!subcmd) {
		fprintf(stderr, "sym: need to specify a subcommand "
			"(try \"help sym\")\n");
		return -1;
	}

	if (!strcasecmp(subcmd, "clear")) {
		if (modify_prompt(MODIFY_SYMS))
			return 0;
		stab_clear();
		modify_clear(MODIFY_SYMS);
		return 0;
	}

	if (!strcasecmp(subcmd, "set")) {
		char *name = get_arg(arg);
		char *val_text = get_arg(arg);
		int value;

		if (!(name && val_text)) {
			fprintf(stderr, "sym: need a name and value to set "
				"symbol table entries\n");
			return -1;
		}

		if (addr_exp(val_text, &value) < 0) {
			fprintf(stderr, "sym: can't parse value: %s\n",
				val_text);
			return -1;
		}

		if (stab_set(name, value) < 0)
			return -1;

		modify_set(MODIFY_SYMS);
		return 0;
	}

	if (!strcasecmp(subcmd, "del"))
		return cmd_sym_del(arg);
	if (!strcasecmp(subcmd, "import"))
		return cmd_sym_load_add(1, arg);
	if (!strcasecmp(subcmd, "import+"))
		return cmd_sym_load_add(0, arg);
	if (!strcasecmp(subcmd, "export"))
		return cmd_sym_savemap(arg);
	if (!strcasecmp(subcmd, "rename"))
		return cmd_sym_rename(arg);
	if (!strcasecmp(subcmd, "find"))
		return cmd_sym_find(arg);

	fprintf(stderr, "sym: unknown subcommand: %s\n", subcmd);
	return -1;
}

static struct command command_sym = {
	.name = "sym",
	.func = cmd_sym,
	.help =
	"sym clear\n"
	"    Clear the symbol table.\n"
	"sym set <name> <value>\n"
	"    Set or overwrite the value of a symbol.\n"
	"sym del <name>\n"
	"    Delete a symbol from the symbol table.\n"
	"sym import <filename>\n"
	"    Load symbols from the given file.\n"
	"sym import+ <filename>\n"
	"    Load additional symbols from the given file.\n"
	"sym export <filename>\n"
	"    Save the current symbols to a BSD-style symbol file.\n"
	"sym find <regex>\n"
	"    Search for symbols by regular expression.\n"
	"sym rename <regex> <string>\n"
	"    Replace every occurance of a pattern in symbol names.\n"
};

int sym_init(void)
{
	register_command(&command_eval);
	register_command(&command_sym);

	return 0;
}