Merge pull request #6 from JLague/master

add (optional) support for more complex Lmod modulefiles

Author: codeandkey

.gitignore

@@ -1,2 +1,3 @@
 mii
 **/*.o
+*.luac

makefile

@@ -1,26 +1,49 @@
-PREFIX ?= /usr
-CC      = gcc
-CFLAGS  = -std=c99 -Wall -Werror -Wno-format-security -pedantic -O3 -DMII_RELEASE -DMII_PREFIX="\"$(PREFIX)\"" -DMII_BUILD_TIME="\"$(shell date)\""
-LDFLAGS =
-OUTPUT  = mii
+PREFIX 	  ?= /usr
+REALPREFIX = $(realpath $(PREFIX))
+CC         = gcc
+CFLAGS     = -std=c99 -Wall -Werror -Wno-format-security -pedantic -O3 -DMII_RELEASE -DMII_PREFIX="\"$(REALPREFIX)\"" -DMII_BUILD_TIME="\"$(shell date)\""
+LDFLAGS    =
+C_OUTPUT   = mii
+OUTPUTS    = $(C_OUTPUT)
 
-SOURCES = $(wildcard src/*.c) src/xxhash/xxhash.c
-OBJECTS = $(SOURCES:.c=.o)
+C_SOURCES = $(wildcard src/*.c) src/xxhash/xxhash.c
+C_OBJECTS = $(C_SOURCES:.c=.o)
 
-all: $(OUTPUT)
+LUA_SOURCES = src/lua/utils.lua src/lua/sandbox.lua
+LUA_OUTPUT  = sandbox.luac
+LUAC        = luac
 
-$(OUTPUT): $(OBJECTS)
-	$(CC) $(OBJECTS) $(LDFLAGS) -o $(OUTPUT)
+MII_ENABLE_LUA  ?= no
+MII_LUA_LDFLAG  ?= -llua
+MII_LUA_INCLUDE ?=
+
+ifeq ($(MII_ENABLE_LUA), yes)
+CFLAGS  += -DMII_ENABLE_LUA $(MII_LUA_INCLUDE)
+LDFLAGS += $(MII_LUA_LDFLAG)
+OUTPUTS += $(LUA_OUTPUT)
+endif
+
+all: $(OUTPUTS)
+
+$(C_OUTPUT): $(C_OBJECTS)
+	$(CC) $(C_OBJECTS) $(LDFLAGS) -o $(C_OUTPUT)
 
 %.o: %.c
 	$(CC) $(CFLAGS) -c $< -o $@
 
+$(LUA_OUTPUT): $(LUA_SOURCES)
+	$(LUAC) -o $@ $^
+
 clean:
-	rm -f $(OUTPUT) $(OBJECTS)
+	rm -f $(C_OUTPUT) $(LUA_OUTPUT) $(C_OBJECTS)
 
-install: $(OUTPUT)
+install: $(OUTPUTS)
 	@echo "Installing mii to $(PREFIX)"
 	mkdir -p $(PREFIX)/bin
 	mkdir -p $(PREFIX)/share/mii
-	cp $(OUTPUT) $(PREFIX)/bin
-	cp -r init $(PREFIX)/share/mii
+	cp $(C_OUTPUT) $(PREFIX)/bin
+	cp -r init  $(PREFIX)/share/mii
+ifeq ($(MII_ENABLE_LUA), yes)
+	mkdir -p $(PREFIX)/share/mii/lua
+	cp $(LUA_OUTPUT) $(PREFIX)/share/mii/lua
+endif

src/analysis.c

@@ -9,18 +9,41 @@
 #include <stdio.h>
 #include <string.h>
 
+#if MII_ENABLE_LUA
+#include <lua.h>
+#include <lualib.h>
+#include <lauxlib.h>
+
+/* After Lua 5.1, lua_objlen changed name and LUA_OK is defined */
+#if LUA_VERSION_NUM <= 501
+#define mii_lua_len lua_objlen
+#define LUA_OK 0
+#else
+#define mii_lua_len lua_rawlen
+#endif
+
+#endif // MII_ENABLE_LUA
+
 #include <dirent.h>
 #include <errno.h>
 #include <regex.h>
 #include <unistd.h>
 #include <sys/stat.h>
 #include <wordexp.h>
 
+#if !MII_ENABLE_LUA
 static const char* _mii_analysis_lmod_regex_src =
     "\\s*(prepend_path|append_path)\\s*\\(\\s*"
     "\"PATH\"\\s*,\\s*\"([^\"]+)\"";
 
 static regex_t _mii_analysis_lmod_regex;
+#else
+/* Lua interpreter state */
+static lua_State *lua_state;
+
+/* run lua module code in a sandbox */
+int _mii_analysis_lua_run(lua_State* lua_state, const char* code, char*** paths_out, int* num_paths_out);
+#endif
 
 /* word expansion functions */
 char* _mii_analysis_expand(const char* expr);
@@ -32,6 +55,7 @@ int _mii_analysis_tcl(const char* path, char*** bins_out, int* num_bins_out);
 /* path scanning functions */
 int _mii_analysis_scan_path(char* path, char*** bins_out, int* num_bins_out);
 
+#if !MII_ENABLE_LUA
 /*
  * compile regexes
  */
@@ -43,12 +67,49 @@ int mii_analysis_init() {
 
     return 0;
 }
+#else
+/*
+ * initialize Lua interpreter
+ */
+int mii_analysis_init() {
+    lua_state = luaL_newstate();
+    luaL_openlibs(lua_state);
+
+    /* sandbox path when mii is installed */
+    char* lua_path = mii_join_path(MII_PREFIX, "share/mii/lua/sandbox.luac");
+
+    if(access(lua_path, F_OK) == 0) {
+        /* found file, try to execute it and return */
+        if(luaL_dofile(lua_state, lua_path) == LUA_OK) {
+            free(lua_path);
+            return 0;
+        }
+    }
+    free(lua_path);
+
+    lua_path = "./sandbox.luac";
+    if(access(lua_path, F_OK) == 0) {
+        /* mii is not installed, but should work anyway */
+        if(luaL_dofile(lua_state, lua_path) == LUA_OK)
+            return 0;
+    }
+
+    mii_error("failed to load Lua file");
+    lua_close(lua_state);
+
+    return -1;
+}
+#endif
 
 /*
- * clean up regexes
+ * cleanup regexes or Lua interpreter
  */
 void mii_analysis_free() {
+#if !MII_ENABLE_LUA
     regfree(&_mii_analysis_lmod_regex);
+#else
+    lua_close(lua_state);
+#endif
 }
 
 /*
@@ -65,20 +126,57 @@ int mii_analysis_run(const char* modfile, int modtype, char*** bins_out, int* nu
     return 0;
 }
 
+#if MII_ENABLE_LUA
+/*
+ * run a modulefile's code in a Lua sandbox
+ */
+int _mii_analysis_lua_run(lua_State* lua_state, const char* code, char*** paths_out, int* num_paths_out) {
+    /* execute modulefile */
+    int res;
+    lua_getglobal(lua_state, "sandbox_run");
+    lua_pushstring(lua_state, code);
+    res = lua_pcall(lua_state, 1, 1, 0);
+
+    if(res != LUA_OK) {
+        mii_error("Error occured in Lua sandbox : %s", lua_tostring(lua_state, -1));
+        lua_pop(lua_state, 1);
+        return -1;
+    }
+
+    luaL_checktype(lua_state, 1, LUA_TTABLE);
+
+    /* allocate memory for the paths */
+    *num_paths_out = mii_lua_len(lua_state, -1);
+    *paths_out = malloc(*num_paths_out * sizeof(char*));
+
+    /* retrieve paths from Lua stack */
+    for (int i = 1; i <= *num_paths_out; ++i) {
+        lua_rawgeti(lua_state, -i, i);
+        (*paths_out)[i-1] = mii_strdup(lua_tostring(lua_state, -1));
+    }
+
+    /* pop every rawgeti + table */
+    lua_pop(lua_state, *num_paths_out + 1);
+
+    return 0;
+}
+#endif
+
 /*
  * extract paths from an lmod file
  */
 int _mii_analysis_lmod(const char* path, char*** bins_out, int* num_bins_out) {
-    char linebuf[MII_ANALYSIS_LINEBUF_SIZE];
-    regmatch_t matches[3];
-
     FILE* f = fopen(path, "r");
 
     if (!f) {
         mii_error("Couldn't open %s for reading : %s", path, strerror(errno));
         return -1;
     }
 
+#if !MII_ENABLE_LUA
+    char linebuf[MII_ANALYSIS_LINEBUF_SIZE];
+    regmatch_t matches[3];
+
     while (fgets(linebuf, sizeof linebuf, f)) {
         /* strip off newline */
         int len = strlen(linebuf);
@@ -94,6 +192,38 @@ int _mii_analysis_lmod(const char* path, char*** bins_out, int* num_bins_out) {
     }
 
     fclose(f);
+#else
+    char* buffer;
+    fseek(f, 0L, SEEK_END);
+    long s = ftell(f);
+    rewind(f);
+    buffer = malloc(s + 1);
+    if ( buffer != NULL ) {
+        fread(buffer, s, 1, f);
+        fclose(f); f = NULL;
+        buffer[s] = '\0';
+
+        /* get binaries paths */
+        char** bin_paths;
+        int num_paths;
+        if(_mii_analysis_lua_run(lua_state, buffer, &bin_paths, &num_paths)) {
+            mii_error("Error occured when executing %s, skipping", path);
+            free(buffer);
+            return -1;
+        }
+
+        /* scan every path returned */
+        for(int i = 0; i < num_paths; ++i) {
+            _mii_analysis_scan_path(bin_paths[i], bins_out, num_bins_out);
+            free(bin_paths[i]);
+        }
+
+        free(bin_paths);
+        free(buffer);
+    }
+    if (f != NULL) fclose(f);
+#endif
+
     return 0;
 }