From 96b522d5218cefe380213e68141980b507e8c765 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alexe=C3=AF=20KADIR?= <alexei.kadir@gmail.com>
Date: Thu, 15 Feb 2024 20:58:50 +0100
Subject: [PATCH] Added some more signatures and implemented more functions

---
 src/backing.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 src/entry.h   | 27 +++++++++++++++
 src/sandbox.c | 16 ++++++++-
 3 files changed, 132 insertions(+), 2 deletions(-)
 create mode 100644 src/entry.h

diff --git a/src/backing.c b/src/backing.c
index d51781a..29240e6 100644
--- a/src/backing.c
+++ b/src/backing.c
@@ -1,6 +1,12 @@
 #include "backing.h"
 
+#include "utils.h"
+
+#include <stdbool.h>
 #include <string.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <dirent.h>
 #include <sys/stat.h>
 
 bool is_valid_backing_name(const char* name) {
@@ -25,7 +31,7 @@ char* get_backing_path(const char* name) {
 	if (name == NULL)
 		return NULL;
 
-	return format("%s/%s", "/var/lib/sandbox/backings", name);
+	return format("%s/%s", "/var/lib/sandbox/backings", name); // TODO: Use a setting for the backings directory
 }
 
 bool backing_exists(const char* name) {
@@ -52,6 +58,57 @@ bool backing_exists(const char* name) {
 	return true;
 }
 
+char** list_backings(void) {
+	// Open the backings directory
+	DIR* dir = opendir("/var/lib/sandbox/backings"); // TODO: Use a setting for the backings directory
+	if (dir == NULL)
+		return NULL;
+
+	// Count the number of backings
+	size_t count = 0;
+	struct dirent* entry;
+	while ((entry = readdir(dir)) != NULL) {
+		if (is_valid_backing_name(entry->d_name))
+			count++;
+	}
+
+	// Allocate the array
+	char** backings = calloc(count + 1, sizeof(char*));
+	if (backings == NULL) {
+		closedir(dir);
+		return NULL;
+	}
+
+	// Reset the directory stream
+	rewinddir(dir);
+
+	// Fill the array
+	size_t i = 0;
+	while ((entry = readdir(dir)) != NULL) {
+		if (is_valid_backing_name(entry->d_name)) {
+			backings[i] = strdup(entry->d_name);
+			if (backings[i] == NULL) {
+				closedir(dir);
+
+				for (size_t j = 0; j < i; j++)
+					free(backings[j]);
+				free(backings);
+
+				return NULL;
+			}
+			i++;
+		}
+	}
+
+	// Close the directory
+	closedir(dir);
+
+	// Terminate the array
+	backings[count] = NULL;
+
+	return backings;
+}
+
 time_t get_backing_ctime(const char* name) {
 	// As the name starts with the ctime, we can just convert the first part of the name to a time_t
 	size_t len = strlen(name);
@@ -68,7 +125,39 @@ time_t get_backing_ctime(const char* name) {
 		return 0;
 
 	time_t ctime = (time_t)strtoull(ctime_str, NULL, 10);
+
 	free(ctime_str);
 
 	return ctime;
 }
+
+char* get_latest_backing(void) {
+	// Get the backings
+	char** backings = list_backings();
+	if (backings == NULL)
+		return NULL;
+
+	// Find the latest backing
+	time_t latest_ctime = 0;
+	char* latest_backing = NULL;
+
+	for (size_t i = 0; backings[i] != NULL; i++) {
+		time_t ctime = get_backing_ctime(backings[i]);
+
+		if (ctime >= latest_ctime) {
+			latest_ctime = ctime;
+			latest_backing = backings[i];
+		}
+	}
+
+	// Duplicate the latest backing
+	if (latest_backing != NULL)
+		latest_backing = strdup(latest_backing);
+
+	// Free the backings
+	for (size_t i = 0; backings[i] != NULL; i++)
+		free(backings[i]);
+	free(backings);
+
+	return latest_backing;
+}
\ No newline at end of file
diff --git a/src/entry.h b/src/entry.h
new file mode 100644
index 0000000..1fce9ea
--- /dev/null
+++ b/src/entry.h
@@ -0,0 +1,27 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <time.h>
+
+bool is_valid_entry_name(const char* name);
+
+char* get_entry_path(const char* name);
+
+bool entry_exists(const char* name);
+
+char* get_entry_disk_path(const char* name);
+
+char** list_entries(void);
+
+time_t get_entry_mtime(const char* name);
+
+char* find_oldest_entry(void);
+
+bool create_entry(const char* name);
+
+bool delete_entry(const char* name);
+
+uint64_t get_available_size(void);
+
+void reserve_space(uint64_t size);
\ No newline at end of file
diff --git a/src/sandbox.c b/src/sandbox.c
index 03418e2..6ca111b 100644
--- a/src/sandbox.c
+++ b/src/sandbox.c
@@ -2,12 +2,26 @@
 
 #include "utils.h"
 
-#include "disk.h"
+#include "backing.h"
 
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 
 int main(int argc, char* argv[]) {
+	char** backings = list_backings();
+
+	if (backings == NULL) {
+		logmsg(LOG_ERROR, "Failed to list backings.");
+		return 1;
+	}
+
+	for (size_t i = 0; backings[i] != NULL; i++) {
+		printf("%s\n", backings[i]);
+		free(backings[i]);
+	}
+
+	free(backings);
+
 	return 0;
 }
\ No newline at end of file