From f6ca4ed80a79408ab55b4a27b73eaa0f32a86410 Mon Sep 17 00:00:00 2001 From: Thorsten Töpper Date: Sat, 21 Jun 2025 16:42:49 +0200 Subject: Rename list_management to data_management --- src/data_management.c | 231 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 231 insertions(+) create mode 100644 src/data_management.c (limited to 'src/data_management.c') diff --git a/src/data_management.c b/src/data_management.c new file mode 100644 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 +#include +#include +#include +#include +#include + +#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; +} + -- cgit v1.2.3-70-g09d2