summaryrefslogtreecommitdiff
path: root/src/zscanner/file_loader.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/zscanner/file_loader.c')
-rw-r--r--src/zscanner/file_loader.c255
1 files changed, 255 insertions, 0 deletions
diff --git a/src/zscanner/file_loader.c b/src/zscanner/file_loader.c
new file mode 100644
index 0000000..ce44dbe
--- /dev/null
+++ b/src/zscanner/file_loader.c
@@ -0,0 +1,255 @@
+/* Copyright (C) 2011 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+ 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include "zscanner/file_loader.h"
+
+#include <inttypes.h> // PRIu64
+#include <unistd.h> // sysconf
+#include <stdio.h> // sprintf
+#include <stdlib.h> // free
+#include <stdbool.h> // bool
+#include <string.h> // strlen
+#include <fcntl.h> // open
+#include <sys/stat.h> // fstat
+#include <sys/mman.h> // mmap
+
+#include "common/errcode.h" // error codes
+
+/*! \brief Mmap block size in bytes. */
+#define BLOCK_SIZE 30000000
+
+/*!
+ * \brief Processes zone settings block.
+ *
+ * Before zone file processing via scanner it's necessary to process first
+ * settings block using this function. Settings block contains ORIGIN and
+ * TTL directive.
+ *
+ * \param fl File loader structure.
+ *
+ * \retval 0 if success.
+ * \retval -1 if error.
+ */
+static int load_settings(file_loader_t *fl)
+{
+ int ret;
+ char *settings_name;
+ scanner_t *settings_scanner;
+
+ // Creating name for zone defaults.
+ size_t buf_len = strlen(fl->file_name) + 100;
+ settings_name = malloc(buf_len);
+ ret = snprintf(settings_name, buf_len, "ZONE DEFAULTS <%s>",
+ fl->file_name);
+ if (ret < 0 || (size_t)ret >= buf_len) {
+ free(settings_name);
+ return -1;
+ }
+
+ // Temporary scanner for zone settings.
+ settings_scanner = scanner_create(settings_name);
+
+ // Use parent processing functions.
+ settings_scanner->process_record = fl->scanner->process_record;
+ settings_scanner->process_error = fl->scanner->process_error;
+
+ // Scanning zone settings.
+ ret = scanner_process(fl->settings_buffer,
+ fl->settings_buffer + fl->settings_length,
+ true,
+ settings_scanner);
+
+ // If no error occured, then copy scanned settings to actual context.
+ if (ret == 0) {
+ memcpy(fl->scanner->zone_origin,
+ settings_scanner->zone_origin,
+ settings_scanner->zone_origin_length);
+ fl->scanner->zone_origin_length =
+ settings_scanner->zone_origin_length;
+ fl->scanner->default_ttl = settings_scanner->default_ttl;
+ }
+
+ // Destroying temporary scanner.
+ scanner_free(settings_scanner);
+
+ free(settings_name);
+
+ return ret;
+}
+
+file_loader_t* file_loader_create(const char *file_name,
+ const char *zone_origin,
+ const uint16_t default_class,
+ const uint32_t default_ttl,
+ void (*process_record)(const scanner_t *),
+ void (*process_error)(const scanner_t *),
+ void *data)
+{
+ int ret;
+
+ // Creating zeroed structure.
+ file_loader_t *fl = calloc(1, sizeof(file_loader_t));
+
+ if (fl == NULL) {
+ return NULL;
+ }
+
+ // Copying file name.
+ fl->file_name = strdup(file_name);
+
+ // Opening zone file.
+ fl->fd = open(fl->file_name, O_RDONLY);
+
+ if (fl->fd == -1) {
+ free(fl->file_name);
+ free(fl);
+ return NULL;
+ }
+
+ // Creating zone scanner.
+ fl->scanner = scanner_create(file_name);
+
+ // Setting processing functions and data pointer.
+ fl->scanner->process_record = process_record;
+ fl->scanner->process_error = process_error;
+ fl->scanner->data = data;
+
+ // Default class initialization.
+ fl->scanner->default_class = default_class;
+
+ // Filling zone settings buffer.
+ ret = snprintf(fl->settings_buffer,
+ sizeof(fl->settings_buffer),
+ "$ORIGIN %s\n"
+ "$TTL %u\n",
+ zone_origin, default_ttl);
+ if (ret <= 0 || (size_t)ret >= sizeof(fl->settings_buffer)) {
+ file_loader_free(fl);
+ return NULL;
+ }
+
+ fl->settings_length = ret;
+
+ return fl;
+}
+
+void file_loader_free(file_loader_t *fl)
+{
+ close(fl->fd);
+ free(fl->file_name);
+ scanner_free(fl->scanner);
+ free(fl);
+}
+
+int file_loader_process(file_loader_t *fl)
+{
+ int ret;
+ char *data; // Mmaped data.
+ bool is_last_block;
+ long page_size;
+ uint64_t n_blocks;
+ uint64_t block_id;
+ uint64_t default_block_size;
+ uint64_t scanner_start; // Current block start to scan.
+ uint64_t block_size; // Current block size to scan.
+ struct stat file_stat;
+
+ // Last block - secure termination of zone file.
+ char *zone_termination = "\n";
+
+ // Getting OS page size.
+ page_size = sysconf(_SC_PAGESIZE);
+
+ // Getting file information.
+ if (fstat(fl->fd, &file_stat) == -1) {
+ return FLOADER_EFSTAT;
+ }
+
+ // Check for directory.
+ if (S_ISDIR(file_stat.st_mode)) {
+ return FLOADER_EDIRECTORY;
+ }
+
+ // Check for empty file.
+ if (file_stat.st_size == 0) {
+ return FLOADER_EEMPTY;
+ }
+
+ // Block size adjustment to multiple of page size.
+ default_block_size = (BLOCK_SIZE / page_size) * page_size;
+
+ // Number of blocks which cover the whole file (ceiling operation).
+ n_blocks = 1 + ((file_stat.st_size - 1) / default_block_size);
+
+ // Process settings using scanner (like initial ORIGIN and TTL).
+ ret = load_settings(fl);
+
+ if (ret != 0) {
+ return FLOADER_EDEFAULTS;
+ }
+
+ // Loop over zone file blocks.
+ for (block_id = 0; block_id < n_blocks; block_id++) {
+ scanner_start = block_id * default_block_size;
+ is_last_block = false;
+ block_size = default_block_size;
+
+ // The last block is probably shorter.
+ if (block_id == (n_blocks - 1)) {
+ block_size = file_stat.st_size - scanner_start;
+ is_last_block = true;
+ }
+
+ // Zone file block mapping.
+ data = mmap(0,
+ block_size,
+ PROT_READ,
+ MAP_SHARED,
+ fl->fd,
+ scanner_start);
+
+ if (data == MAP_FAILED) {
+ return FLOADER_EMMAP;
+ }
+
+ // Scan zone file.
+ ret = scanner_process(data,
+ data + block_size,
+ false,
+ fl->scanner);
+
+ // Artificial last block containing newline char only.
+ if (is_last_block == true && fl->scanner->stop == 0) {
+ ret = scanner_process(zone_termination,
+ zone_termination + 1,
+ true,
+ fl->scanner);
+ }
+
+ // Zone file block unmapping.
+ if (munmap(data, block_size) == -1) {
+ return FLOADER_EMUNMAP;
+ }
+ }
+
+ // Check for scanner return.
+ if (ret != 0) {
+ return FLOADER_ESCANNER;
+ }
+
+ return KNOT_EOK;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-26 21:53:17 +0000