--- /dev/null
+/* Copyright (c) 2010. The SimGrid Team.
+ * All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+/* SimGrid Lua helper functions */
+
+#include "lua_utils.h"
+#include "xbt.h"
+#include "xbt/log.h"
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua_utils, lua, "Lua helper functions");
+
+/**
+ * @brief Returns a string representation of a value in the Lua stack.
+ *
+ * This function is for debugging purposes.
+ * It always returns the same pointer.
+ *
+ * @param L the Lua state
+ * @param index index in the stack
+ * @return a string representation of the value at this index
+ */
+const char* sglua_tostring(lua_State* L, int index) {
+
+ static char buff[64];
+
+ switch (lua_type(L, index)) {
+
+ case LUA_TNIL:
+ sprintf(buff, "nil");
+ break;
+
+ case LUA_TNUMBER:
+ sprintf(buff, "%.3f", lua_tonumber(L, index));
+ break;
+
+ case LUA_TBOOLEAN:
+ sprintf(buff, "%s", lua_toboolean(L, index) ? "true" : "false");
+ break;
+
+ case LUA_TSTRING:
+ snprintf(buff, 63, "'%s'", lua_tostring(L, index));
+ break;
+
+ case LUA_TFUNCTION:
+ if (lua_iscfunction(L, index)) {
+ sprintf(buff, "C-function");
+ }
+ else {
+ sprintf(buff, "function");
+ }
+ break;
+
+ case LUA_TTABLE:
+ sprintf(buff, "table(%p)", lua_topointer(L, index));
+ break;
+
+ case LUA_TLIGHTUSERDATA:
+ case LUA_TUSERDATA:
+ sprintf(buff, "userdata(%p)", lua_touserdata(L, index));
+ break;
+
+ case LUA_TTHREAD:
+ sprintf(buff, "thread");
+ break;
+ }
+ return buff;
+}
+
+/**
+ * @brief Returns a string representation of a key-value pair.
+ *
+ * This function is for debugging purposes.
+ * It always returns the same pointer.
+ *
+ * @param L the Lua state
+ * @param key_index index of the key
+ * @param value_index index of the value
+ * @return a string representation of the key-value pair
+ */
+const char* sglua_keyvalue_tostring(lua_State* L, int key_index, int value_index) {
+
+ static char buff[64];
+ /* value_tostring also always returns the same pointer */
+ int len = snprintf(buff, 63, "[%s] -> ", sglua_tostring(L, key_index));
+ snprintf(buff + len, 63 - len, "%s", sglua_tostring(L, value_index));
+ return buff;
+}
+
+/**
+ * @brief Returns a string composed of the specified number of spaces.
+ *
+ * This function can be used to indent strings for debugging purposes.
+ * It always returns the same pointer.
+ *
+ * @param length length of the string
+ * @return a string of this length with only spaces
+ */
+const char* sglua_get_spaces(int length) {
+
+ static char spaces[128];
+
+ xbt_assert(length < 128);
+ memset(spaces, ' ', length);
+ spaces[length] = '\0';
+ return spaces;
+}
+
+/**
+ * @brief Dumps the Lua stack if debug logs are enabled.
+ * @param msg a message to print
+ * @param L a Lua state
+ */
+void sglua_stack_dump(const char* msg, lua_State* L)
+{
+ if (XBT_LOG_ISENABLED(lua_utils, xbt_log_priority_debug)) {
+ char buff[2048];
+ char* p = buff;
+ int i;
+ int top = lua_gettop(L);
+
+ //if (1) return;
+
+ fflush(stdout);
+
+ p[0] = '\0';
+ for (i = 1; i <= top; i++) { /* repeat for each level */
+
+ p += sprintf(p, "%s", sglua_tostring(L, i));
+ p += sprintf(p, " "); /* put a separator */
+ }
+ XBT_DEBUG("%s%s", msg, buff);
+ }
+}
+
+/**
+ * @brief Writes the specified data into a memory buffer.
+ *
+ * This function is a valid lua_Writer that writes into a memory buffer passed
+ * as userdata.
+ * TODO: use a dynar as userdata
+ *
+ * @param L a lua state
+ * @param source some data
+ * @param sz number of bytes of data
+ * @param user_data the memory buffer to write
+ */
+int sglua_memory_writer(lua_State* L, const void* source, size_t size,
+ void* userdata) {
+
+ buffer_t buffer = (buffer_t) userdata;
+ while (buffer->capacity < buffer->size + size) {
+ buffer->capacity *= 2;
+ buffer->data = xbt_realloc(buffer->data, buffer->capacity);
+ }
+ memcpy(buffer->data + buffer->size, source, size);
+ buffer->size += size;
+
+ return 0;
+}
