Add various functions for Lua directory handling and path info

This adds new functions to get plugins path info, find out if a directory
exists, make a new one, remove one, etc. It also creates a file environment
for user-supplied Lua scripts, to prevent global variable contamination as
well as supply the script-specific file name.  Some other minor cleanup was
done as I found them.

A new testsuite was added to test the existing and new directory functions.

Change-Id: I19bd587b5e8a73d89b8521af73670e023314fb33
Reviewed-on: https://code.wireshark.org/review/832
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 383 insertions, 0 deletions

diff --git a/epan/wslua/wslua_dir.c b/epan/wslua/wslua_dir.c
new file mode 100644
index 0000000000..d39484df48
--- /dev/null
+++ b/epan/wslua/wslua_dir.c
@@ -0,0 +1,383 @@
+/*
+ *  wslua_dir.c
+ *
+ * (c) 2014, Hadriel Kaplan <hadrielk at yahoo dot com>
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+
+/* WSLUA_MODULE Dir Directory handling functions */
+
+#include "wslua.h"
+#include <wsutil/file_util.h>
+
+WSLUA_CLASS_DEFINE(Dir,FAIL_ON_NULL("Dir"),NOP); /* A Directory object, as well as associated functions. */
+
+WSLUA_CONSTRUCTOR Dir_make(lua_State* L) {
+    /* Creates a directory.
+
+       The created directory is set for permission mode 0755 (octal), meaning it is
+       read+write+execute by owner, but only read+execute by group and others.
+
+       IF the directory was created successfully, a boolean `true` is returned.
+       If the directory cannot be made because it already exists, `false` is returned.
+       If the directory cannot be made because an error occurred, `nil` is returned.
+
+       @since 1.11.3
+    */
+#define WSLUA_ARG_Dir_make_NAME 1 /* The name of the directory, possibly including path. */
+
+    const char *dir_path = luaL_checkstring(L, WSLUA_ARG_Dir_make_NAME);
+    ws_statb64 s_buf;
+    int ret;
+
+    if (ws_stat64(dir_path, &s_buf) != 0 && errno == ENOENT) {
+        ret = ws_mkdir(dir_path, 0755);
+        if (ret == -1) {
+            lua_pushnil(L);
+        } else {
+            lua_pushboolean(L, 1);
+        }
+    } else {
+        lua_pushboolean(L, 0);
+    }
+
+    WSLUA_RETURN(1); /* Boolean `true` on success, `false` if already exists, `nil` on error. */
+}
+
+WSLUA_CONSTRUCTOR Dir_exists(lua_State* L) {
+    /* Returns true if the given directory name exists.
+
+       If the directory exists, a boolean `true` is returned.
+       If the path is a file instead, `false` is returned.
+       If the path does not exist or an error occurred, `nil` is returned.
+
+       @since 1.11.3
+    */
+#define WSLUA_ARG_Dir_exists_NAME 1 /* The name of the directory, possibly including path. */
+
+    const char *dir_path = luaL_checkstring(L, WSLUA_ARG_Dir_exists_NAME);
+    int ret;
+
+    if ((ret = test_for_directory (dir_path)) == EISDIR) {
+        lua_pushboolean(L, 1);
+    } else {
+        if (ret == 0) {
+            lua_pushboolean(L, 0);
+        } else {
+            lua_pushnil(L);
+        }
+    }
+
+    WSLUA_RETURN(1); /* Boolean `true` if the directory exists, `false` if it's a file, `nil` on error/not-exist. */
+}
+
+WSLUA_CONSTRUCTOR Dir_remove(lua_State* L) {
+    /* Removes an empty directory.
+
+       If the directory was removed successfully, a boolean `true` is returned.
+       If the directory cannot be removed because it does not exist, `false` is returned.
+       If the directory cannot be removed because an error occurred, `nil` is returned.
+
+       This function only removes empty directories. To remove a directory regardless,
+       use `Dir.remove_all()`.
+
+       @since 1.11.3
+    */
+#define WSLUA_ARG_Dir_remove_NAME 1 /* The name of the directory, possibly including path. */
+
+    const char *dir_path = luaL_checkstring(L, WSLUA_ARG_Dir_remove_NAME);
+    int ret;
+
+    if (test_for_directory (dir_path) == EISDIR) {
+        ret = ws_remove(dir_path);
+        if (ret != 0) {
+            lua_pushnil(L);
+        } else {
+            lua_pushboolean(L, 1);
+        }
+    } else {
+        lua_pushboolean(L, 0);
+    }
+
+    WSLUA_RETURN(1); /* Boolean `true` on success, `false` if does not exist, `nil` on error. */
+}
+
+static int delete_directory(const char *directory) {
+    WS_DIR *dir;
+    WS_DIRENT *file;
+    gchar *filename;
+    int ret = 0;
+
+    /* delete all contents of directory */
+    if ((dir = ws_dir_open(directory, 0, NULL)) != NULL) {
+        while ((file = ws_dir_read_name(dir)) != NULL) {
+            filename = g_strdup_printf ("%s%s%s", directory, G_DIR_SEPARATOR_S,
+                            ws_dir_get_name(file));
+            if (test_for_directory(filename) != EISDIR) {
+                ret = ws_remove(filename);
+            } else {
+                /* recurse */
+                ret = delete_directory (filename);
+            }
+            if (ret != 0) {
+                break;
+            }
+            g_free (filename);
+        }
+        ws_dir_close(dir);
+    }
+
+    if (ret == 0) {
+        ret = ws_remove(directory);
+    }
+
+    return ret;
+}
+
+
+WSLUA_CONSTRUCTOR Dir_remove_all(lua_State* L) {
+    /* Removes an empty or non-empty directory.
+
+       If the directory was removed successfully, a boolean `true` is returned.
+       If the directory cannot be removed because it does not exist, `false` is returned.
+       If the directory cannot be removed because an error occurred, `nil` is returned.
+
+       @since 1.11.3
+    */
+#define WSLUA_ARG_Dir_remove_all_NAME 1 /* The name of the directory, possibly including path. */
+
+    const char *dir_path = luaL_checkstring(L, WSLUA_ARG_Dir_remove_all_NAME);
+    int ret;
+
+    if (test_for_directory (dir_path) == EISDIR) {
+        ret = delete_directory(dir_path);
+        if (ret != 0) {
+            lua_pushnil(L);
+        } else {
+            lua_pushboolean(L, 1);
+        }
+    } else {
+        lua_pushboolean(L, 0);
+    }
+
+    WSLUA_RETURN(1); /* Boolean `true` on success, `false` if does not exist, `nil` on error. */
+}
+
+WSLUA_CONSTRUCTOR Dir_open(lua_State* L) {
+    /* Opens a directory and returns a `Dir` object representing the files in the directory.
+
+       @code for filename in Dir.open(path) do ... end @endcode
+    */
+#define WSLUA_ARG_Dir_open_PATHNAME 1 /* The pathname of the directory. */
+#define WSLUA_OPTARG_Dir_open_EXTENSION 2 /* If given, only files with this extension will be returned. */
+
+    const char* dirname = luaL_checkstring(L,WSLUA_ARG_Dir_open_PATHNAME);
+    const char* extension = luaL_optstring(L,WSLUA_OPTARG_Dir_open_EXTENSION,NULL);
+    Dir dir;
+    char* dirname_clean;
+
+    if (!dirname) {
+        WSLUA_ARG_ERROR(Dir_open,PATHNAME,"must be a string");
+        return 0;
+    }
+
+    dirname_clean = wslua_get_actual_filename(dirname);
+    if (!dirname_clean) {
+        WSLUA_ARG_ERROR(Dir_open,PATHNAME,"directory does not exist");
+        return 0;
+    }
+
+    if (!test_for_directory(dirname_clean))  {
+        g_free(dirname_clean);
+        WSLUA_ARG_ERROR(Dir_open,PATHNAME, "must be a directory");
+        return 0;
+    }
+
+    dir = (Dir)g_malloc(sizeof(struct _wslua_dir));
+    dir->dir = g_dir_open(dirname_clean, 0, dir->dummy);
+    g_free(dirname_clean);
+    dir->ext = extension ? g_strdup(extension) : NULL;
+    dir->dummy = (GError **)g_malloc(sizeof(GError *));
+    *(dir->dummy) = NULL;
+
+    if (dir->dir == NULL) {
+        g_free(dir->dummy);
+        g_free(dir);
+
+        WSLUA_ARG_ERROR(Dir_open,PATHNAME,"could not open directory");
+        return 0;
+    }
+
+    pushDir(L,dir);
+    WSLUA_RETURN(1); /* the `Dir` object. */
+}
+
+WSLUA_METAMETHOD Dir__call(lua_State* L) {
+    /* At every invocation will return one file (nil when done). */
+
+    Dir dir = checkDir(L,1);
+    const gchar* file;
+    const gchar* filename;
+    const char* ext;
+
+    if (!dir->dir) {
+        return 0;
+    }
+
+    if ( ! ( file = g_dir_read_name(dir->dir ) )) {
+        g_dir_close(dir->dir);
+        dir->dir = NULL;
+        return 0;
+    }
+
+
+    if ( ! dir->ext ) {
+        lua_pushstring(L,file);
+        return 1;
+    }
+
+    do {
+        filename = file;
+
+        /* XXX strstr returns ptr to first match,
+            this fails ext=".xxx" filename="aaa.xxxz.xxx"  */
+        if ( ( ext = strstr(filename,dir->ext)) && g_str_equal(ext,dir->ext) ) {
+            lua_pushstring(L,filename);
+            return 1;
+        }
+    } while(( file = g_dir_read_name(dir->dir) ));
+
+    g_dir_close(dir->dir);
+    dir->dir = NULL;
+    return 0;
+}
+
+WSLUA_METHOD Dir_close(lua_State* L) {
+    /* Closes the directory. */
+    Dir dir = checkDir(L,1);
+
+    if (dir->dir) {
+        g_dir_close(dir->dir);
+        dir->dir = NULL;
+    }
+
+    return 0;
+}
+
+WSLUA_CONSTRUCTOR Dir_personal_config_path(lua_State* L) {
+    /* Gets the personal configuration directory path, with filename if supplied.
+
+       @since 1.11.3
+    */
+#define WSLUA_OPTARG_personal_config_path_FILENAME 1 /* A filename. */
+    const char *fname = luaL_optstring(L, WSLUA_OPTARG_personal_config_path_FILENAME,"");
+    char* filename = get_persconffile_path(fname,FALSE);
+
+    lua_pushstring(L,filename);
+    g_free(filename);
+    WSLUA_RETURN(1); /* The full pathname for a file in the personal configuration directory. */
+}
+
+WSLUA_CONSTRUCTOR Dir_global_config_path(lua_State* L) {
+    /* Gets the global configuration directory path, with filename if supplied.
+
+       @since 1.11.3
+    */
+#define WSLUA_OPTARG_global_config_path_FILENAME 1 /* A filename */
+    const char *fname = luaL_optstring(L, WSLUA_OPTARG_global_config_path_FILENAME,"");
+    char* filename;
+
+    if (running_in_build_directory()) {
+        /* Running in build directory, set datafile_path to wslua source directory */
+        filename = g_strdup_printf("%s" G_DIR_SEPARATOR_S "epan" G_DIR_SEPARATOR_S "wslua"
+                                   G_DIR_SEPARATOR_S "%s", get_datafile_dir(), fname);
+    } else {
+        filename = get_datafile_path(fname);
+    }
+
+    lua_pushstring(L,filename);
+    g_free(filename);
+    WSLUA_RETURN(1); /* The full pathname for a file in wireshark's configuration directory. */
+}
+
+WSLUA_CONSTRUCTOR Dir_personal_plugins_path(lua_State* L) {
+    /* Gets the personal plugins directory path.
+
+       @since 1.11.3
+    */
+    char* filename = get_plugins_pers_dir();
+    lua_pushstring(L,filename);
+    g_free(filename);
+    WSLUA_RETURN(1); /* The pathname for the personal plugins directory. */
+}
+
+WSLUA_CONSTRUCTOR Dir_global_plugins_path(lua_State* L) {
+    /* Gets the global plugins directory path.
+
+       @since 1.11.3
+    */
+    lua_pushstring(L, get_plugin_dir());
+    WSLUA_RETURN(1); /* The pathname for the global plugins directory. */
+}
+
+/* Gets registered as metamethod automatically by WSLUA_REGISTER_CLASS/META */
+static int Dir__gc(lua_State* L) {
+    Dir dir = toDir(L,1);
+
+    if(!dir) return 0;
+
+    if (dir->dir) {
+        g_dir_close(dir->dir);
+    }
+
+    g_free(dir->dummy);
+
+    if (dir->ext) g_free(dir->ext);
+
+    g_free(dir);
+
+    return 0;
+}
+
+WSLUA_METHODS Dir_methods[] = {
+    WSLUA_CLASS_FNREG(Dir,make),
+    WSLUA_CLASS_FNREG(Dir,exists),
+    WSLUA_CLASS_FNREG(Dir,remove),
+    WSLUA_CLASS_FNREG(Dir,remove_all),
+    WSLUA_CLASS_FNREG(Dir,open),
+    WSLUA_CLASS_FNREG(Dir,close),
+    WSLUA_CLASS_FNREG(Dir,personal_config_path),
+    WSLUA_CLASS_FNREG(Dir,global_config_path),
+    WSLUA_CLASS_FNREG(Dir,personal_plugins_path),
+    WSLUA_CLASS_FNREG(Dir,global_plugins_path),
+    { NULL, NULL }
+};
+
+WSLUA_META Dir_meta[] = {
+    WSLUA_CLASS_MTREG(Dir,call),
+    { NULL, NULL }
+};
+
+int Dir_register(lua_State* L) {
+    WSLUA_REGISTER_CLASS(Dir);
+    return 0;
+}