Logger: Start implementing the logger_index

logger/logger_index.c

+/*******************************************************************************
+ * This file is part of SWIFT.
+ * Copyright (c) 2019 Loic Hausammann (loic.hausammann@epfl.ch)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser 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 Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ ******************************************************************************/
+
+/* Config parameters. */
+#include "../config.h"
+
+/* Some standard headers. */
+#include <stdio.h>
+
+/* This object's header. */
+#include "logger_index.h"
+
+#include "logger_tools.h"
+
+/**
+ * @brief Initialize the #logger_index.
+ *
+ * @param index The #logger_index.
+ * @param reader The #logger_reader.
+ * @param basename The basename of the index files.
+ */
+void logger_index_init(struct logger_index *index, struct logger_reader *reader,
+		       char *basename) {
+
+  /* Set pointers to 0 */
+  index->offsets = NULL;
+  index->ids = NULL;
+}
+
+/**
+ * @brief Read a single index file.
+ *
+ * @param index The #logger_index.
+ * @param i The index of the file.
+ */
+void logger_index_read_file(struct logger_index *index, int i) {
+  /* Cleanup the memory of previous file */
+  logger_index_free_current_file(index);
+
+  /* Open file */
+  FILE *f = NULL;
+  f = fopen(index->filenames[i], "wb");
+
+  /* Read the double time */
+  double time;
+  fread(&time, sizeof(double), 1, f);
+
+  /* Read integer time */
+  double int_time;
+  fread(&int_time, sizeof(integertime_t), 1, f);
+
+  /* Read the number of particles */
+  long long N_total[swift_type_count];
+  fread(N_total, sizeof(long long), swift_type_count, f);
+
+  /* Count total number of particles */
+  long long N = 0;
+  for(int i = 0; i < swift_type_count; i++) {
+    N += N_total[i];
+  }
+
+  /* Read Ids */
+  if (posix_memalign((void**)&index->ids, IO_BUFFER_ALIGNMENT,
+                     N * sizeof(long long)) != 0)
+    error("Unable to allocate the offset buffer");
+
+  fread(index->ids, sizeof(size_t), N, f);
+
+  /* Read offsets */
+  if (posix_memalign((void**)&index->offsets, IO_BUFFER_ALIGNMENT,
+                     N * sizeof(size_t)) != 0)
+    error("Unable to allocate the offset buffer");
+
+  fread(index->offset, sizeof(size_t), N, f);
+
+
+  /* Close file */
+  fclose(f);
+}
+
+/**
+ * @brief Free the memory allocated for current file.
+ *
+ * @param index The #logger_index.
+ */
+void logger_index_free_current_file(struct logger_index *index) {
+  /* Free offsets */
+  if (index->offsets)
+    free(index->offsets);
+  index->offsets = NULL;
+
+  /* Free ids */
+  if (index->ids)
+    free(index->ids);
+  index->ids = NULL;  
+}
+
+/**
+ * @brief Free the memory.
+ *
+ * @param index The #logger_index.
+ */
+void logger_index_free(struct logger_index *index) {
+
+  /* Free the memory allocated for current file */
+  logger_index_free_file_data(index);
+
+  /* Free the filenames */
+  for(int i = 0; i < index->number_files; i++) {
+    if (index->filenames[i])
+      free(index->filenames[i]);
+    index->filenames[i] = NULL;
+  }
+
+  /* Free the array of filenames */
+  free(index->filenames);
+  index->filenames = NULL;
+}

logger/logger_index.h

@@ -23,10 +23,38 @@
 #ifndef __LOGGER_LOGGER_INDEX_H__
 #define __LOGGER_LOGGER_INDEX_H__
 
+struct logger_reader;
+
 /**
  * @brief This structure will contain the data related to
  *   the index file.
  */
-struct logger_index {};
+struct logger_index {
+  /* The reader */
+  struct logger_reader *reader;
+
+  /* List of the time for each file */
+  double *times;
+
+  /* Number of files */
+  int number_files;
+
+  /* List of all the index files */
+  char **filenames;
+
+  /* Offsets */
+  size_t *offsets;
+
+  /* ids */
+  long long ids;
+};
+
+void logger_index_init(struct logger_index *index, struct logger_reader *reader,
+		       char *basename);
+void logger_index_read_file(struct logger_index *index, int i);
+
+void logger_index_free(struct logger_index *index);
+
+void logger_index_free_current_file(struct logger_index *index);
 
 #endif // __LOGGER_LOGGER_INDEX_H__