From 89d675c474a6717d9daa8b5d9ff2c0f2c03666f9 Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@meshlink.io>
Date: Wed, 28 Oct 2015 22:06:21 +0100
Subject: [PATCH] Add a function to destroy a MeshLink instance.

This will remove all configuration files related to a MeshLink instance.
---
 src/meshlink++.h | 13 +++++++++++++
 src/meshlink.c   | 43 +++++++++++++++++++++++++++++++++++++++++++
 src/meshlink.h   | 12 ++++++++++++
 test/basic.c     | 14 ++++++++++++++
 test/basicpp.cpp | 12 ++++++++++++
 5 files changed, 94 insertions(+)

diff --git a/src/meshlink++.h b/src/meshlink++.h
index f1a3b962..8e0745e4 100644
--- a/src/meshlink++.h
+++ b/src/meshlink++.h
@@ -540,6 +540,19 @@ namespace meshlink {
 		return meshlink_strerror(err);
 	}
 
+	/// Destroy a MeshLink instance.
+	/** This function remove all configuration files of a MeshLink instance. It should only be called when the application
+	 *  does not have an open handle to this instance. Afterwards, a call to meshlink_open() will create a completely
+	 *  new instance.
+	 *
+	 *  @param confbase The directory in which MeshLink stores its configuration files.
+	 *                  After the function returns, the application is free to overwrite or free @a confbase @a.
+	 *
+	 *  @return         This function will return true if the MeshLink instance was succesfully destroyed, false otherwise.
+	 */
+	static bool destroy(const char *confbase) {
+		return meshlink_destroy(confbase);
+	}
 }
 
 #endif // MESHLINKPP_H
diff --git a/src/meshlink.c b/src/meshlink.c
index cbbb64d3..e9250e25 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -1049,6 +1049,49 @@ void meshlink_close(meshlink_handle_t *mesh) {
 	free(mesh);
 }
 
+static void deltree(const char *dirname) {
+	DIR *d = opendir(dirname);
+	if(d) {
+		struct dirent *ent;
+		while((ent = readdir(d))) {
+			if(ent->d_name[0] == '.')
+				continue;
+			char filename[PATH_MAX];
+			snprintf(filename, sizeof filename, "%s" SLASH "%s", dirname, ent->d_name);
+			if(unlink(filename))
+				deltree(filename);
+		}
+		closedir(d);
+	}
+	rmdir(dirname);
+	return;
+}
+
+bool meshlink_destroy(const char *confbase) {
+	if(!confbase) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	char filename[PATH_MAX];
+	snprintf(filename, sizeof filename, "%s" SLASH "meshlink.conf", confbase);
+
+	if(unlink(filename)) {
+		if(errno == ENOENT) {
+			meshlink_errno = MESHLINK_ENOENT;
+			return false;
+		} else {
+			logger(NULL, MESHLINK_ERROR, "Cannot delete %s: %s\n", filename, strerror(errno));
+			meshlink_errno = MESHLINK_ESTORAGE;
+			return false;
+		}
+	}
+
+	deltree(confbase);
+
+	return true;
+}
+
 void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb) {
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
diff --git a/src/meshlink.h b/src/meshlink.h
index 1f4bb726..cca5db1a 100644
--- a/src/meshlink.h
+++ b/src/meshlink.h
@@ -196,6 +196,18 @@ extern void meshlink_stop(meshlink_handle_t *mesh);
  */
 extern void meshlink_close(meshlink_handle_t *mesh);
 
+/// Destroy a MeshLink instance.
+/** This function remove all configuration files of a MeshLink instance. It should only be called when the application
+ *  does not have an open handle to this instance. Afterwards, a call to meshlink_open() will create a completely
+ *  new instance.
+ *
+ *  @param confbase The directory in which MeshLink stores its configuration files.
+ *                  After the function returns, the application is free to overwrite or free @a confbase @a.
+ *
+ *  @return         This function will return true if the MeshLink instance was succesfully destroyed, false otherwise.
+ */
+extern bool meshlink_destroy(const char *confbase);
+
 /// A callback for receiving data from the mesh.
 /** @param mesh      A handle which represents an instance of MeshLink.
  *  @param source    A pointer to a meshlink_node_t describing the source of the data.
diff --git a/test/basic.c b/test/basic.c
index 626d06f6..93b7f5e9 100644
--- a/test/basic.c
+++ b/test/basic.c
@@ -1,5 +1,7 @@
 #include <stdio.h>
 #include <string.h>
+#include <unistd.h>
+#include <errno.h>
 
 #include "meshlink.h"
 
@@ -79,5 +81,17 @@ int main(int argc, char *argv[]) {
 
 	meshlink_close(mesh);
 
+	// Destroy the mesh.
+
+	if(!meshlink_destroy("basic_conf")) {
+		fprintf(stderr, "Could not destroy configuration\n");
+		return 1;
+	}
+
+	if(!access("basic_conf", F_OK) || errno != ENOENT) {
+		fprintf(stderr, "Configuration not fully destroyed\n");
+		return 1;
+	}
+
 	return 0;
 }
diff --git a/test/basicpp.cpp b/test/basicpp.cpp
index 34c0bacb..3a0c75ac 100644
--- a/test/basicpp.cpp
+++ b/test/basicpp.cpp
@@ -1,5 +1,7 @@
 #include <cstring>
 #include <iostream>
+#include <unistd.h>
+#include <cerrno>
 
 #include "meshlink++.h"
 
@@ -71,5 +73,15 @@ int main(int argc, char *argv[]) {
 
 	mesh.stop();
 
+	if(!meshlink::destroy("basicpp_conf")) {
+		cerr << "Could not destroy configuration\n";
+		return 1;
+	}
+
+	if(!access("basic.conf", F_OK) || errno != ENOENT) {
+		cerr << "Configuration not fully destroyed\n";
+		return 1;
+	}
+
 	return 0;
 }
-- 
2.39.2