journal.c

aee是一种易使用的文本编辑器。你可以不用说明书来使用它。它提供终端接口和本地的X-windows接口。它的特性包括即弹的菜单

	while (((ret_val = open(lock_file_name, (O_CREAT | O_EXCL), 0700)) == -1) && (counter < 3))
	{
		sleep(1);
		counter++;
	}
	if (ret_val != -1)
		close(ret_val);
	return(ret_val);
}

/*
 |	remove the lock file
 */

void 
unlock_journal_fd()
{
	unlink(lock_file_name);
}

/*
 |	free the memory used in the list of files being edited and their 
 |	journal files
 */

void 
free_db_list(list)
struct journal_db *list;
{
	if (list->next != NULL)
		free_db_list(list->next);
	free(list->journal_name);
	if (list->file_name != NULL)
		free(list->file_name);
	free(list);
}

/*
 |	read the file ~/.aeeinfo (which contains the name of the file 
 |	being edited and the name of the journal file associated with it)
 */

struct journal_db *
read_journal_db()
{
	char buffer[4092];
	char *tmp;
	int file_name_len;
	int journ_name_len;
	struct journal_db *top_of_list = NULL;
	struct journal_db *list = NULL;
	FILE *db_fp;

	if (lock_journal_fd() == -1)
		return(NULL);

	if (db_file_name == NULL)
		db_file_name = resolve_name("~/.aeeinfo");
	db_fp = fopen(db_file_name, "r");

	if (db_fp == NULL)
	{
		unlock_journal_fd();
		return(NULL);
	}

	while ((tmp = fgets(buffer, 4092, db_fp)) != NULL)
	{
		if (list == NULL)
			top_of_list = list = 
			     (struct journal_db *) malloc(sizeof(struct journal_db));
		else
		{
			list->next = (struct journal_db *) 
					malloc(sizeof(struct journal_db));
			list = list->next;
		}
		list->next = NULL;

		if ((*tmp == ' ') || (*tmp == '\t'))
			tmp = next_word(tmp);
		file_name_len = atoi(tmp);
		tmp = next_word(tmp);
		journ_name_len = atoi(tmp);

		if (file_name_len > 0)
		{
			tmp = next_word(tmp);
			list->file_name = (char *) malloc(file_name_len + 1);
			strncpy(list->file_name, tmp, file_name_len);
			list->file_name[file_name_len] = (char)NULL;
		}
		else
			list->file_name = NULL;

		tmp = next_word(tmp);
		list->journal_name = (char *) malloc(journ_name_len + 1);
		strncpy(list->journal_name, tmp, journ_name_len);
		list->journal_name[journ_name_len] = (char)NULL;
	}
	fclose(db_fp);
	return(top_of_list);
}

/*
 |	Write the file ~/.aeeinfo .
 */

void 
write_db_file(list)
struct journal_db *list;
{
	struct journal_db *tmp;
	FILE *db_fp;

	db_fp = fopen(db_file_name, "w");

	if (db_fp == NULL)
		return;

	for (tmp = list; (db_fp != NULL) && (tmp != NULL); tmp = tmp->next)
	{
		if (tmp->file_name != (char)NULL)
		{
			fprintf(db_fp, "%d %d %s %s\n", strlen(tmp->file_name), 
				strlen(tmp->journal_name), tmp->file_name, 
							tmp->journal_name);
		}
		else
		{
			fprintf(db_fp, "%d %d %s\n", 0, 
				strlen(tmp->journal_name), tmp->journal_name);
		}
	}

	fclose(db_fp);

	unlock_journal_fd();

}

/*
 |	add an entry to the file ~/.aeeinfo (a new file being edited and 
 |	its associated journal file)
 */

void 
add_to_journal_db(buffer)
struct bufr *buffer;
{
	struct journal_db *top_of_list;
	struct journal_db *list;

	top_of_list = list = read_journal_db();
	if (list == (struct journal_db *) -1)	/* could not open lock file */
		return;

	if (list == NULL)
	{
		top_of_list = list = 
			(struct journal_db *) malloc(sizeof(struct journal_db));
	}
	else
	{
		/*
		 |	Could check for duplicate file being edited here.
		 */

		while (list->next != NULL)
			list = list->next;
		list->next = (struct journal_db *) malloc(sizeof(struct journal_db));
		list = list->next;
	}
	list->next = NULL;

	list->journal_name = strdup(buffer->journal_file);
	if (*buffer->full_name != (char)NULL)
		list->file_name = strdup(buffer->full_name);
	else
		list->file_name = NULL;

	write_db_file(top_of_list);
	free_db_list(top_of_list);
}

/*
 |	remove an entry from the file ~/.aeeinfo (the editor is being 
 |	exited and it is time to delete the journal file, so remove the 
 |	reference)
 */

void 
rm_journal_db_entry(buffer)
struct bufr *buffer;
{
	struct journal_db *top_of_list;
	struct journal_db *list;
	struct journal_db *tmp;
	int changed = FALSE;

	top_of_list = list = read_journal_db();
	if (list == (struct journal_db *) NULL)	/* could not open db file */
	{
		return;
	}

	if ((!strcmp(buffer->journal_file, top_of_list->journal_name)) && 
		((top_of_list->file_name == NULL) || 
		   ((top_of_list->file_name != NULL) && 
		    (!strcmp(buffer->full_name, top_of_list->file_name)))))
	{
		top_of_list = list->next;
		tmp = list;
		changed = TRUE;
	}
	else
	{
		while (((list->next != NULL) && 
		      (!((list->next->file_name != NULL) && 
			    (!strcmp(buffer->full_name, list->next->file_name) 
		 && !strcmp(buffer->journal_file, list->next->journal_name)))))
		  && (!((list->next->file_name == NULL) && 
		     !strcmp(buffer->journal_file, list->next->journal_name))))
		{
 			list = list->next;
		}
		if (list->next != NULL)
		{
			tmp = list->next;
			list->next = list->next->next;
			changed = TRUE;
		}
	}
	if (changed == TRUE)
	{
		if (top_of_list == NULL)	/* no entries for file	*/
		{
			unlink(db_file_name);
			unlock_journal_fd();
		}
		else
		{
			write_db_file(top_of_list);
		}
		tmp->next = NULL;
		free_db_list(tmp);
	}
	else
		unlock_journal_fd();

	if (top_of_list != NULL)
		free_db_list(top_of_list);
}

/*
 |	check for the existence of a directory, and if it doesn't exist 
 |	create it (will recursively go through and create the directory 
 |	from the highest location where a directory does exist)
 */

int
create_dir(name)
char *name;
{
	char *path;
	struct stat buf;
	int ret_val;

	ret_val = stat(name, &buf);
	if (ret_val == -1)
	{
		path = ae_dirname(name);
		ret_val = create_dir(path);
		if (ret_val != -1)
			ret_val = mkdir(name, 0700);
		free(path);
	}
	return(ret_val);
}

/*
 |	determine a name for a journal file and make sure no other journal 
 |	file of that name already exists (if one does, create a name based
 |	on the current date and time)
 */

void 
journal_name(buffer, file_name)
struct bufr *buffer;
char *file_name;
{
	char *temp, *buff, *name;
	int count;

	if (*file_name == (char)NULL)
		file_name = "no_file_journal";

	if ((journal_dir != NULL) && (*journal_dir != (char) NULL))
	{
		name = ae_basename(file_name);
		buffer->journal_file = temp = 
			xalloc(strlen(name) + 5 + strlen(journal_dir));
		strcpy(temp, journal_dir);
		strcat(temp, "/");
		strcat(temp, name);
	}

	if (buffer->journal_file == NULL)
	{
		buffer->journal_file = temp = xalloc(strlen(file_name) + 4);
		strcpy(temp, file_name);
	}

	buff = ae_basename(temp);

	temp = buff;

	if (strlen(temp) >= (MAX_NAME_LEN - 3))
	{
		for (count = 1; count < (MAX_NAME_LEN - 3); count++)
			temp++;
	}
	else
	{
		while(*temp != (char) NULL)
			temp++;
	}

	copy_str(".rv", temp);
}

/*
 |	create and initialize the journal file
 */

void 
open_journal_for_write(buffer)
struct bufr *buffer;
{
	int ret_val;
	int length;
	int counter;
	char *temp;
	struct tm *time_info;
	time_t t;

	if (((buffer->journ_fd = 
		open(buffer->journal_file, (O_CREAT | O_EXCL | O_WRONLY), 0600)) == -1) && 
				(errno == EEXIST))
	{
		/*
		 |	file already exists
		 */
		buffer->journal_file = realloc(buffer->journal_file, 
					(strlen(buffer->journal_file) + 17));
		/*
		 |	find the last '/'
		 */
		temp = strrchr(buffer->journal_file, '/');

		if (temp != NULL)
			temp++;
		else
			temp = buffer->journal_file;

		/*
		 |	create a file name based on the date, e.g., 
		 |	950913221206.rv
		 |	Not a guarantee of uniqueness, but certainly not 
		 |	likely to be repeated.
		 */
		t = time(NULL);
		time_info = gmtime(&t);
		ret_val = strftime(temp, 16, "%y%m%d%H%M%S.rv", time_info);

		/*
		 |	For some extra paranoia, check this one, and append 
		 |	a character (a-z) to get uniqueness.
		 */

		counter = 'a';
		length = strlen (buffer->journal_file);
		while (((buffer->journ_fd = 
			open(buffer->journal_file, (O_CREAT | O_EXCL | O_WRONLY), 0600)) == -1) 
				&& (errno == EEXIST) && (counter <= 'z'))
		{
			buffer->journal_file[length] = counter;
			buffer->journal_file[length + 1] = (char) NULL;
			counter++;
		}
	}

	if (buffer->journ_fd == -1)
	{
		wprintw(com_win, cant_opn_rcvr_fil_msg);
		buffer->journalling = FALSE;
		return;
	}

	add_to_journal_db(buffer);

	if (*buffer->full_name != (char) NULL)
	{
		ret_val = write(buffer->journ_fd, buffer->full_name, 
					strlen(buffer->full_name));
	}
	ret_val |= write(buffer->journ_fd, "\n", 1);

	journ_info_init(buffer, buffer->first_line);
}

/*
 |	delete a journal file and delete its entry from the file ~/.aeeinfo
 */

void 
remove_journal_file(buffer)
struct bufr *buffer;
{
	close(buffer->journ_fd);
	unlink(buffer->journal_file);
	rm_journal_db_entry(buffer);
}