--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lib-dict/dict-file.c	Sun Oct 19 02:07:34 2008 +0300
@@ -0,0 +1,401 @@
+/* Copyright (c) 2008 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "array.h"
+#include "hash.h"
+#include "file-dotlock.h"
+#include "nfs-workarounds.h"
+#include "istream.h"
+#include "ostream.h"
+#include "dict-private.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+struct file_dict {
+	struct dict dict;
+	pool_t hash_pool;
+
+	char *path;
+	struct hash_table *hash;
+	int fd;
+};
+
+struct file_dict_iterate_context {
+	struct dict_iterate_context ctx;
+
+	struct hash_iterate_context *iter;
+	char *path;
+	unsigned int path_len;
+
+	enum dict_iterate_flags flags;
+	unsigned int failed:1;
+};
+
+enum file_dict_change_type {
+	FILE_DICT_CHANGE_TYPE_SET,
+	FILE_DICT_CHANGE_TYPE_UNSET,
+	FILE_DICT_CHANGE_TYPE_INC
+};
+
+struct file_dict_change {
+	enum file_dict_change_type type;
+	const char *key;
+	union {
+		const char *str;
+		long long diff;
+	} value;
+};
+
+struct file_dict_transaction_context {
+	struct dict_transaction_context ctx;
+
+	pool_t pool;
+	ARRAY_DEFINE(changes, struct file_dict_change);
+};
+
+static struct dotlock_settings file_dict_dotlock_settings = {
+	MEMBER(temp_prefix) NULL,
+	MEMBER(lock_suffix) NULL,
+
+	MEMBER(timeout) 30,
+	MEMBER(stale_timeout) 5
+};
+
+static struct dict *file_dict_init(struct dict *driver, const char *uri,
+				   enum dict_data_type value_type ATTR_UNUSED,
+				   const char *username ATTR_UNUSED)
+{
+	struct file_dict *dict;
+	
+	dict = i_new(struct file_dict, 1);
+	dict->dict = *driver;
+	dict->path = i_strdup(uri);
+	dict->hash_pool = pool_alloconly_create("file dict", 1024);
+	dict->hash = hash_create(default_pool, dict->hash_pool, 0, str_hash,
+				 (hash_cmp_callback_t *)strcmp);
+	dict->fd = -1;
+	return &dict->dict;
+}
+
+static void file_dict_deinit(struct dict *_dict)
+{
+	struct file_dict *dict = (struct file_dict *)_dict;
+
+	hash_destroy(&dict->hash);
+	pool_unref(&dict->hash_pool);
+	i_free(dict->path);
+	i_free(dict);
+}
+
+static bool file_dict_need_refresh(struct file_dict *dict)
+{
+	struct stat st1, st2;
+
+	if (dict->fd == -1)
+		return TRUE;
+
+	nfs_flush_file_handle_cache(dict->path);
+	if (nfs_safe_stat(dict->path, &st1) < 0) {
+		i_error("stat(%s) failed: %m", dict->path);
+		return FALSE;
+	}
+
+	if (fstat(dict->fd, &st2) < 0) {
+		if (errno != ESTALE)
+			i_error("fstat(%s) failed: %m", dict->path);
+		return TRUE;
+	}
+	if (st1.st_ino != st2.st_ino ||
+	    !CMP_DEV_T(st1.st_dev, st2.st_dev)) {
+		/* file changed */
+		return TRUE;
+	}
+	return FALSE;
+}
+
+static int file_dict_refresh(struct file_dict *dict)
+{
+	struct istream *input;
+	char *key, *value;
+
+	if (!file_dict_need_refresh(dict))
+		return 0;
+
+	if (dict->fd != -1) {
+		if (close(dict->fd) < 0)
+			i_error("close(%s) failed: %m", dict->path);
+	}
+	dict->fd = open(dict->path, O_RDONLY);
+	if (dict->fd == -1) {
+		if (errno == ENOENT)
+			return 0;
+		i_error("open(%s) failed: %m", dict->path);
+		return -1;
+	}
+
+	hash_clear(dict->hash, TRUE);
+	p_clear(dict->hash_pool);
+
+	input = i_stream_create_fd(dict->fd, (size_t)-1, FALSE);
+	while ((key = i_stream_read_next_line(input)) != NULL &&
+	       (value = i_stream_read_next_line(input)) != NULL) {
+		key = p_strdup(dict->hash_pool, key);
+		value = p_strdup(dict->hash_pool, value);
+		hash_insert(dict->hash, key, value);
+	}
+	i_stream_destroy(&input);
+	return 0;
+}
+
+static int file_dict_lookup(struct dict *_dict, pool_t pool,
+			    const char *key, const char **value_r)
+{
+	struct file_dict *dict = (struct file_dict *)_dict;
+
+	if (file_dict_refresh(dict) < 0)
+		return -1;
+
+	*value_r = p_strdup(pool, hash_lookup(dict->hash, key));
+	return *value_r == NULL ? 0 : 1;
+}
+
+static struct dict_iterate_context *
+file_dict_iterate_init(struct dict *_dict, const char *path,
+		       enum dict_iterate_flags flags)
+{
+        struct file_dict_iterate_context *ctx;
+	struct file_dict *dict = (struct file_dict *)_dict;
+
+	ctx = i_new(struct file_dict_iterate_context, 1);
+	ctx->path = i_strdup(path);
+	ctx->path_len = strlen(path);
+	ctx->flags = flags;
+	ctx->iter = hash_iterate_init(dict->hash);
+
+	if (file_dict_refresh(dict) < 0)
+		ctx->failed = TRUE;
+	return &ctx->ctx;
+}
+
+static int file_dict_iterate(struct dict_iterate_context *_ctx,
+			     const char **key_r, const char **value_r)
+{
+	struct file_dict_iterate_context *ctx =
+		(struct file_dict_iterate_context *)_ctx;
+	void *key, *value;
+
+	while (hash_iterate(ctx->iter, &key, &value)) {
+		if (strncmp(ctx->path, key, ctx->path_len) != 0)
+			continue;
+
+		if ((ctx->flags & DICT_ITERATE_FLAG_RECURSE) == 0 &&
+		    strchr(key + ctx->path_len, '/') != NULL)
+			continue;
+
+		*key_r = key;
+		*value_r = value;
+		return 1;
+	}
+	return ctx->failed ? -1 : 0;
+}
+
+static void file_dict_iterate_deinit(struct dict_iterate_context *_ctx)
+{
+	struct file_dict_iterate_context *ctx =
+		(struct file_dict_iterate_context *)_ctx;
+
+	hash_iterate_deinit(&ctx->iter);
+	i_free(ctx->path);
+	i_free(ctx);
+}
+
+static struct dict_transaction_context *
+file_dict_transaction_init(struct dict *_dict)
+{
+	struct file_dict_transaction_context *ctx;
+	pool_t pool;
+
+	pool = pool_alloconly_create("file dict transaction", 1024);
+	ctx = p_new(pool, struct file_dict_transaction_context, 1);
+	ctx->ctx.dict = _dict;
+	ctx->pool = pool;
+	p_array_init(&ctx->changes, pool, 32);
+	return &ctx->ctx;
+}
+
+static void file_dict_apply_changes(struct file_dict_transaction_context *ctx)
+{
+	struct file_dict *dict = (struct file_dict *)ctx->ctx.dict;
+	const char *tmp;
+	char *key, *value, *old_value;
+	void *orig_key, *orig_value;
+	const struct file_dict_change *changes;
+	unsigned int i, count, new_len;
+	long long diff;
+
+	changes = array_get(&ctx->changes, &count);
+	for (i = 0; i < count; i++) {
+		if (hash_lookup_full(dict->hash, changes[i].key,
+				     &orig_key, &orig_value)) {
+			key = orig_key;
+			old_value = orig_value;
+		} else {
+			key = NULL;
+			old_value = NULL;
+		}
+		value = NULL;
+
+		switch (changes[i].type) {
+		case FILE_DICT_CHANGE_TYPE_INC:
+			diff = old_value == NULL ? 0 :
+				strtoll(old_value, NULL, 10);
+			diff += changes[i].value.diff;
+			tmp = t_strdup_printf("%lld", diff);
+			new_len = strlen(tmp);
+			if (new_len > strlen(old_value))
+				value = p_strdup(dict->hash_pool, tmp);
+			else {
+				memcpy(old_value, tmp, new_len + 1);
+				value = old_value;
+			}
+			/* fall through */
+		case FILE_DICT_CHANGE_TYPE_SET:
+			if (key == NULL)
+				key = p_strdup(dict->hash_pool, changes[i].key);
+			if (value == NULL) {
+				value = p_strdup(dict->hash_pool,
+						 changes[i].value.str);
+			}
+			hash_update(dict->hash, key, value);
+			break;
+		case FILE_DICT_CHANGE_TYPE_UNSET:
+			if (old_value != NULL)
+				hash_remove(dict->hash, key);
+			break;
+		}
+	}
+}
+
+static int file_dict_write_changes(struct file_dict_transaction_context *ctx)
+{
+	struct file_dict *dict = (struct file_dict *)ctx->ctx.dict;
+	struct dotlock *dotlock;
+	struct hash_iterate_context *iter;
+	struct ostream *output;
+	void *key, *value;
+	int fd;
+
+	fd = file_dotlock_open(&file_dict_dotlock_settings, dict->path, 0,
+			       &dotlock);
+	if (fd == -1) {
+		i_error("file dict commit: file_dotlock_open() failed: %m");
+		return -1;
+	}
+	/* refresh once more now that we're locked */
+	if (file_dict_refresh(dict) < 0) {
+		file_dotlock_delete(&dotlock);
+		return -1;
+	}
+	file_dict_apply_changes(ctx);
+
+	output = o_stream_create_fd(fd, 0, FALSE);
+	iter = hash_iterate_init(dict->hash);
+	while (hash_iterate(iter, &key, &value)) {
+		o_stream_send_str(output, key);
+		o_stream_send(output, "\n", 1);
+		o_stream_send_str(output, value);
+		o_stream_send(output, "\n", 1);
+	}
+	hash_iterate_deinit(&iter);
+	o_stream_destroy(&output);
+
+	if (file_dotlock_replace(&dotlock,
+				 DOTLOCK_REPLACE_FLAG_DONT_CLOSE_FD) < 0) {
+		(void)close(fd);
+		return -1;
+	}
+
+	if (dict->fd != -1)
+		(void)close(dict->fd);
+	dict->fd = fd;
+	return 0;
+}
+
+static int file_dict_transaction_commit(struct dict_transaction_context *_ctx)
+{
+	struct file_dict_transaction_context *ctx =
+		(struct file_dict_transaction_context *)_ctx;
+	int ret;
+
+	ret = file_dict_write_changes(ctx);
+	pool_unref(&ctx->pool);
+	return ret;
+}
+
+static void file_dict_transaction_rollback(struct dict_transaction_context *_ctx)
+{
+	struct file_dict_transaction_context *ctx =
+		(struct file_dict_transaction_context *)_ctx;
+
+	pool_unref(&ctx->pool);
+}
+
+static void file_dict_set(struct dict_transaction_context *_ctx,
+			  const char *key, const char *value)
+{
+	struct file_dict_transaction_context *ctx =
+		(struct file_dict_transaction_context *)_ctx;
+	struct file_dict_change *change;
+
+	change = array_append_space(&ctx->changes);
+	change->type = FILE_DICT_CHANGE_TYPE_SET;
+	change->key = p_strdup(ctx->pool, key);
+	change->value.str = p_strdup(ctx->pool, value);
+}
+
+static void file_dict_unset(struct dict_transaction_context *_ctx,
+			    const char *key)
+{
+	struct file_dict_transaction_context *ctx =
+		(struct file_dict_transaction_context *)_ctx;
+	struct file_dict_change *change;
+
+	change = array_append_space(&ctx->changes);
+	change->type = FILE_DICT_CHANGE_TYPE_UNSET;
+	change->key = p_strdup(ctx->pool, key);
+}
+
+static void
+file_dict_atomic_inc(struct dict_transaction_context *_ctx,
+		     const char *key, long long diff)
+{
+	struct file_dict_transaction_context *ctx =
+		(struct file_dict_transaction_context *)_ctx;
+	struct file_dict_change *change;
+
+	change = array_append_space(&ctx->changes);
+	change->type = FILE_DICT_CHANGE_TYPE_INC;
+	change->key = p_strdup(ctx->pool, key);
+	change->value.diff = diff;
+}
+
+struct dict dict_driver_file = {
+	MEMBER(name) "file",
+	{
+		file_dict_init,
+		file_dict_deinit,
+		file_dict_lookup,
+		file_dict_iterate_init,
+		file_dict_iterate,
+		file_dict_iterate_deinit,
+		file_dict_transaction_init,
+		file_dict_transaction_commit,
+		file_dict_transaction_rollback,
+		file_dict_set,
+		file_dict_unset,
+		file_dict_atomic_inc
+	}
+};