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-rw-r--r--src/data_management.c231
1 files changed, 231 insertions, 0 deletions
diff --git a/src/data_management.c b/src/data_management.c
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index 0000000..a0a1667
--- /dev/null
+++ b/src/data_management.c
@@ -0,0 +1,231 @@
+/* SPDX-License-Identifier: Apache-2.0 */
+
+/* Copyright 2025 Thorsten Töpper
+ *
+ * vim:ts=4:sw=4:expandtab
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <dirent.h>
+#include <sys/stat.h>
+
+#include "output.h"
+#include "data_management.h"
+#include "options.h"
+
+
+
+/* === IMPLEMENTATION === */
+
+inline struct list_node *create_node(char *fname, struct stat *ln_stat) {
+ struct list_node *node = NULL;
+
+ if (fname == NULL || fname[0] == '\0') {
+ LOGERR("ERROR: No valid filename given\n");
+ return NULL;
+ }
+
+ if (ln_stat == NULL) {
+ LOGERR("ERROR: No valid file information given\n");
+ return NULL;
+ }
+
+ if ((node = calloc(1, sizeof(struct list_node))) == NULL) {
+ LOGERR("ERROR: Failed allocate memory for node: %s\n", strerror(errno));
+ return NULL;
+ }
+
+ node->next = NULL;
+ /* With strncpy and strict compiler options it complained. A file name
+ * can't be longer than 256 bytes, including the string terminating \0
+ * byte at the end. As the code no longer's in the same file...*/
+ memcpy(node->fname, fname, 255);
+ node->fname[255] = '\0';
+ memcpy(&(node->ln_stat), ln_stat, sizeof(struct stat));
+ return node;
+}
+
+
+inline void destroy_list(struct list_head *list) {
+ struct list_node *ptr = NULL;
+ if (list == NULL)
+ return;
+ while (list->first != NULL) {
+ ptr = list->first->next;
+ if (ptr == NULL) {
+ free(list->first);
+ break;
+ }
+ list->first->next = ptr->next;
+ free(ptr);
+ }
+ free(list);
+}
+
+
+/* dirty... */
+#define INSERT_BY_NUMERIC_FIELD(list, node, field) \
+{ struct list_node *ptr = NULL; \
+ if (node->ln_stat.field > list->first->ln_stat.field) { \
+ node->next = list->first; list->first = node; return 0; } \
+ ptr = list->first; \
+ while (ptr != NULL) { \
+ if (ptr->next == NULL) { ptr->next = node; return 0; } \
+ if (node->ln_stat.field > ptr->next->ln_stat.field) { \
+ node->next = ptr->next; ptr->next = node; \
+ return 0; } \
+ ptr = ptr->next; \
+ } \
+}
+
+
+inline int insert_sorted_by_size(struct list_head *list, struct list_node *node) {
+ if (list == NULL) { LOGERR("ERROR: No list given.\n"); return -1; }
+ if (node == NULL) { LOGERR("ERROR: No node given.\n"); return -2; }
+
+ if (list->first == NULL) {
+ list->first = node;
+ return 0;
+ }
+ INSERT_BY_NUMERIC_FIELD(list, node, st_size);
+ return -3;
+}
+
+inline int insert_sorted_by_time(struct list_head *list, struct list_node *node) {
+ if (list == NULL) { LOGERR("ERROR: No list given.\n"); return -1; }
+ if (node == NULL) { LOGERR("ERROR: No node given.\n"); return -2; }
+
+ if (list->first == NULL) {
+ list->first = node;
+ return 0;
+ }
+ switch (option_time_field) {
+ case 'm': /* default setting first */
+ INSERT_BY_NUMERIC_FIELD(list, node, st_mtim.tv_sec);
+ break;
+ case 'a':
+ INSERT_BY_NUMERIC_FIELD(list, node, st_atim.tv_sec);
+ break;
+ case 'c':
+ INSERT_BY_NUMERIC_FIELD(list, node, st_ctim.tv_sec);
+ break;
+ default:
+ LOGERR("WARNING: option_time_field has invalid value %c 0x%02X - going by default m\n",
+ option_time_field, option_time_field);
+ INSERT_BY_NUMERIC_FIELD(list, node, st_mtim.tv_sec);
+ break;
+ };
+ return -3;
+}
+
+
+inline struct list_head *create_list_sort_reversed(struct list_head *list) {
+ struct list_head *lh = NULL;
+ struct list_node *cpynode = NULL, *ptr = NULL;
+ if (list == NULL) {
+ LOGERR("ERROR: No list given\n");
+ return NULL;
+ }
+ if ((lh = calloc(1, sizeof(struct list_head))) == NULL) {
+ LOGERR("ERROR: Failed to allocate memory for a struct list_head\n");
+ return NULL;
+ }
+
+ lh->first = NULL;
+ ptr = list->first;
+
+ while (ptr != NULL) {
+ cpynode = create_node(ptr->fname, &(ptr->ln_stat));
+ if (cpynode == NULL) {
+ destroy_list(lh);
+ return NULL;
+ }
+ cpynode->next = lh->first;
+ lh->first = cpynode;
+ ptr = ptr->next;
+ }
+
+ return lh;
+}
+
+/* This function contains the only time critical code. The loop over
+ * the directory content.
+ *
+ * Note for future:
+ * I myself use the dir_monitor in combination with watch on a directory
+ * containing temporary data, it may happen that a run into an error occurs,
+ * but it's not tragic. To reduce the chance of the error the first step
+ * would be to optimize the loop with putting the data into a list in stack
+ * form and moving the nodes into a sorted list afterwards.
+ */
+struct list_head *get_data_from_directory(char *path) {
+ char *fullpath = NULL, *fname_in_path = NULL;
+ DIR *dir = NULL;
+ size_t l;
+ struct dirent *de = NULL;
+ struct list_node *tmp = NULL;
+ struct list_head *list = NULL;
+ struct stat stat_res;
+
+ if (path == NULL) {
+ LOGERR("ERROR: No path given.\n");
+ return NULL;
+ }
+
+ l = strlen(path);
+ /* 258 filename and possibly required PATH_SEP and of course string termination */
+ if ((fullpath = calloc(l+258, sizeof(char))) == NULL) {
+ LOGERR("ERROR: Failed to allocate memory for list head.\n");
+ return NULL;
+ }
+ sprintf(fullpath, "%s%c", path, ((path[l-1] == PATH_SEP) ? '\0' : PATH_SEP));
+ fname_in_path = (fullpath[l] == PATH_SEP) ? &(fullpath[l+1]) : &(fullpath[l]) ;
+
+ if ((dir = opendir(path)) == NULL) {
+ LOGERR("ERROR: Failed to open directory '%s': %s (errno %d)\n",
+ path, strerror(errno), errno);
+ return NULL;
+ }
+
+ /* TBH: In case those few bytes are not available, the process will be killed anyways */
+ if ((list = calloc(1, sizeof(struct list_head))) == NULL) {
+ LOGERR("ERROR: Failed to allocate memory for list head.\n");
+ closedir(dir);
+ return NULL;
+ }
+
+ errno = 0;
+ /* Currently the code is specific UNIXoid, needs to be adjusted in case someone ports it. */
+ while ((de = readdir(dir)) != NULL) {
+ if (de->d_name[0] == '.' && option_show_hidden_entries == false)
+ continue;
+
+ sprintf(fname_in_path, "%s", de->d_name);
+ DBGTRC("DEBUG: fullpath: '%s'\n", fullpath);
+ if (lstat(fullpath, &stat_res) != 0) {
+ LOGERR("ERROR: lstat call on '%s' failed: %s (errno %d)\n",
+ fullpath, strerror(errno), errno);
+ continue;
+ }
+ if ((tmp = create_node(de->d_name, &stat_res)) == NULL) {
+ LOGERR("ERROR: Skipping entry %s\n", de->d_name);
+ continue;
+ }
+ /* SORT_BY_SIZE is the default value, always check it first. */
+ switch (option_sort_type) {
+ case SORT_BY_SIZE:
+ insert_sorted_by_size(list, tmp);
+ break;
+ case SORT_BY_TIME:
+ insert_sorted_by_time(list, tmp);
+ break;
+ };
+ }
+
+ free(fullpath);
+ closedir(dir);
+ return list;
+}
+
generated by cgit v1.2.3-70-g09d2 (git 2.51.0) at 2025-12-29 10:58:36 +0000