Fix GCC 7 string truncation warning, too small temporary buffer

In GCC 7 the -Wall infers the new -Wformat-truncation which finds
problems with string truncation in functions like snprintf().

This patch fixes a possibly problem in path name creation which,
combined with the scandir() function, might cause loss of .conf
files, failure to call run-parts properly, and kill services at
shutdown.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/conf.c

@@ -470,7 +470,7 @@ int conf_reload_dynamic(void)
 
 	for (i = 0; i < num; i++) {
 		char *name = e[i]->d_name;
-		char  path[CMD_SIZE];
+		char  path[LINE_SIZE];
 		size_t len;
 		struct stat st;
 		struct timeval mtime;

src/exec.c

@@ -354,7 +354,7 @@ int run_parts(char *dir, char *cmd)
 		mode_t mode;
 		char *args[NUM_ARGS];
 		char *name = e[i]->d_name;
-		char path[CMD_SIZE];
+		char path[LINE_SIZE];
 
 		snprintf(path, sizeof(path), "%s/%s", dir, name);
 		mode = fmode(path);

src/sig.c

@@ -116,7 +116,7 @@ void do_kill(int signo)
 		while ((d = readdir(dirp))) {
 			int pid;
 			FILE *fp;
-			char file[80] = "";
+			char file[LINE_SIZE] = "";
 
 			if (d->d_type != DT_DIR)
 				continue;