Only warn once about disk shortage in case database and log file are on the same device (e.g. both on / )

Signed-off-by: DL6ER <dl6er@dl6er.de>

src/database/message-table.c

@@ -685,11 +685,11 @@ void log_resource_shortage(const double load, const int nprocs, const int shmem,
 	else if(disk > -1)
 	{
 		// Get filesystem details for this path
-		struct fstab *fsdetails = get_filesystem_details(path);
+		struct mntent *fsdetails = get_filesystem_details(path);
 
 		// Create plain message
 		if(fsdetails != NULL)
-			ret = snprintf(buf, sizeof(buf), "Disk shortage ahead: %d%% is used (%s) on filesystem mounted at %s", disk, msg, fsdetails->fs_file);
+			ret = snprintf(buf, sizeof(buf), "Disk shortage ahead: %d%% is used (%s) on filesystem mounted at %s", disk, msg, fsdetails->mnt_dir);
 		else
 			ret = snprintf(buf, sizeof(buf), "Disk shortage ahead: %d%% is used (%s) on partition containing the file %s", disk, msg, path);
 
@@ -708,16 +708,13 @@ void log_resource_shortage(const double load, const int nprocs, const int shmem,
 		// Create HTML message
 		if(fsdetails != NULL)
 			ret = snprintf(buf, sizeof(buf), "Disk shortage ahead: <strong>%d%%</strong> is used (%s) on filesystem mounted at <code>%s</code>",
-			               disk, msg, fsdetails->fs_file);
+			               disk, msg, fsdetails->mnt_dir);
 		else
 			ret = snprintf(buf, sizeof(buf), "Disk shortage ahead: <strong>%d%%</strong> is used (%s) on partition containing the file <code>%s</code>",
 			               disk, msg, path);
 		if(ret > (int)sizeof(buf))
 			log_warn("log_resource_shortage(): Buffer too small to hold HTML message, warning truncated");
 
-		// Rewind fsdetails to the beginning of the list
-		endfsent();
-
 		add_html_message(item, buf);
 	}
 }

src/files.c

@@ -250,26 +250,29 @@ unsigned int get_path_usage(const char *path, char buffer[64])
 }
 
 // Get the filesystem where the given path is located
-// Credits: https://stackoverflow.com/a/40660348/2087442
-struct fstab *get_filesystem_details(const char *path) {
+struct mntent *get_filesystem_details(const char *path)
+{
 	/* stat the file in question */
 	struct stat path_stat;
 	stat(path, &path_stat);
 
 	/* iterate through the list of devices */
-	struct fstab *fs = NULL;
-	while( (fs = getfsent()) )
+	FILE *aFile = setmntent("/proc/mounts", "r");
+	struct mntent *ent;
+	while((ent = getmntent(aFile)) != NULL)
 	{
 		/* stat the mount point */
 		struct stat dev_stat;
-		stat(fs->fs_file, &dev_stat);
+		stat(ent->mnt_dir, &dev_stat);
 
 		/* check if our file and the mount point are on the same device */
 		if( dev_stat.st_dev == path_stat.st_dev )
 			break;
 	}
 
-	return fs;
+	endmntent(aFile);
+
+	return ent;
 }
 
 // Credits: https://stackoverflow.com/a/55410469

src/files.h

@@ -12,8 +12,8 @@
 
 #include <stdbool.h>
 #include <sys/stat.h>
-// getfsent()
-#include <fstab.h>
+// setmntent()
+#include <mntent.h>
 
 #define ZIP_ROTATIONS 3
 #define MAX_ROTATIONS 15
@@ -25,7 +25,7 @@ unsigned long long get_FTL_db_filesize(void);
 void get_permission_string(char permissions[10], struct stat *st);
 void ls_dir(const char* path);
 unsigned int get_path_usage(const char *path, char buffer[64]);
-struct fstab *get_filesystem_details(const char *path);
+struct mntent *get_filesystem_details(const char *path);
 bool directory_exists(const char *path);
 void rotate_files(const char *path, char **first_file);
 

src/gc.c

@@ -276,6 +276,18 @@ static void runGC(const time_t now, time_t *lastGCrun)
 	DBdeleteoldqueries = true;
 }
 
+static bool check_files_on_same_device(const char *path1, const char *path2)
+{
+	struct stat s1, s2;
+	if(stat(path1, &s1) != 0 || stat(path2, &s2) != 0)
+	{
+		log_warn("check_files_on_same_device(): stat() failed: %s", strerror(errno));
+		return false;
+	}
+
+	return s1.st_dev == s2.st_dev;
+}
+
 void *GC_thread(void *val)
 {
 	// Set thread name
@@ -292,6 +304,9 @@ void *GC_thread(void *val)
 	unsigned int LastLogStorageUsage = 0;
 	unsigned int LastDBStorageUsage = 0;
 
+	bool db_and_log_on_same_dev = false;
+	db_and_log_on_same_dev = check_files_on_same_device(config.files.database.v.s, config.files.log.ftl.v.s);
+
 	// Create inotify watcher for pihole.toml config file
 	watch_config(true);
 
@@ -319,9 +334,17 @@ void *GC_thread(void *val)
 		// Check available resources
 		if(now - lastResourceCheck >= RCinterval)
 		{
+			// Check load averages
 			check_load();
+
+			// Check disk space of database file
 			LastDBStorageUsage = check_space(config.files.database.v.s, LastDBStorageUsage);
-			LastLogStorageUsage = check_space(config.files.log.ftl.v.s, LastLogStorageUsage);
+
+			// Check disk space of log file only if they are not on
+			// the same file system
+			if(!db_and_log_on_same_dev)
+				LastLogStorageUsage = check_space(config.files.log.ftl.v.s, LastLogStorageUsage);
+
 			lastResourceCheck = now;
 		}