Re: [Minios-devel] [UNIKRAFT/LIBLUA PATCH 2/3] Add Makefile.uk and main loop glue code

["Justin He (Arm Technology China)" <Justin.He@xxxxxxx>]

Hi Felipe

> -----Original Message-----
> From: Minios-devel <minios-devel-bounces@xxxxxxxxxxxxxxxxxxxx> On Behalf
> Of Felipe Huici
> Sent: 2019年8月28日 23:29
> To: minios-devel@xxxxxxxxxxxxx
> Cc: Felipe Huici <felipe.huici@xxxxxxxxx>; Simon Kuenzer
> <simon.kuenzer@xxxxxxxxx>
> Subject: [Minios-devel] [UNIKRAFT/LIBLUA PATCH 2/3] Add Makefile.uk and
> main loop glue code
>
> This is a port of lua to Unikraft as an external library. It requires
> libc, so in your application Makefile the library dependency list
> should read:
>
>            LIBS := ...:$(UK_LIBS)/newlib:$(UK_LIBS)/lua:...
>
> Please refer to README.md for information on running it.
>
> Signed-off-by: Felipe Huici <felipe.huici@xxxxxxxxx>
> Signed-off-by: Simon Kuenzer <simon.kuenzer@xxxxxxxxx>
> ---
>  Makefile.uk | 100 ++++++++++
>  lua.c       | 620
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++
>  2 files changed, 720 insertions(+)
>  create mode 100644 Makefile.uk
>  create mode 100644 lua.c
>
> diff --git a/Makefile.uk b/Makefile.uk
> new file mode 100644
> index 0000000..bdb3093
> --- /dev/null
> +++ b/Makefile.uk
> @@ -0,0 +1,100 @@
> +#########################################################
> #######################
> +# Library registration
> +#########################################################
> #######################
> +$(eval $(call addlib_s,liblua,$(CONFIG_LIBLUA)))
> +
> +#########################################################
> #######################
> +# Sources
> +#########################################################
> #######################
> +LIBLUA_VERSION=5.3.5
> +LIBLUA_TARBALL=lua-$(LIBLUA_VERSION)
> +LIBLUA_URL=https://www.lua.org/ftp/$(LIBLUA_TARBALL).tar.gz
> +
> +$(eval $(call fetch,liblua,$(LIBLUA_URL)))
> +
> +#########################################################
> #######################
> +# Helpers
> +#########################################################
> #######################
> +LIBLUA_SRCS_BASE=$(LIBLUA_ORIGIN)/$(LIBLUA_TARBALL)/src
> +
> +#########################################################
> #######################
> +# Library includes
> +#########################################################
> #######################
> +# Put public headers of the library to a public folder and export them
> globally.
> +# The prepare step below takes care of populating the folder.
> +$(call mk_sub_build_dir,liblua/include)
> +CINCLUDES-$(CONFIG_LIBLUA)   += -I$(LIBLUA_BUILD)/include
> +CPPINCLUDES-$(CONFIG_LIBLUA) += -I$(LIBLUA_BUILD)/include
> +
> +# Private headers
> +LIBLUA_CINCLUDES-y += -I$(LIBLUA_SRCS_BASE)
> +
> +#########################################################
> #######################
> +# Compilation unit
> +#########################################################
> #######################
> +LIBLUA_CFLAGS-y += -DLUA_COMPAT_5_2
> +
> +# Main loop
> +LIBLUA_SRCS-y += $(LIBLUA_BASE)/lua.c
> +
> +# CORE_O
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lapi.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lcode.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lctype.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/ldebug.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/ldo.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/ldump.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lfunc.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lgc.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/llex.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lmem.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lobject.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lopcodes.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lparser.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lstate.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lstring.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/ltable.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/ltm.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lundump.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lvm.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lzio.c
> +
> +# LIB_O
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lauxlib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lbaselib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lbitlib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lcorolib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/ldblib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/liolib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lmathlib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/loslib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lstrlib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/ltablib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/lutf8lib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/loadlib.c
> +LIBLUA_SRCS-y += $(LIBLUA_SRCS_BASE)/linit.c
> +
> +
> +#########################################################
> #######################
> +# libray API headers
> +#########################################################
> #######################
> +$(LIBLUA_SRCS_BASE)/%.h: $(LIBLUA_BUILD)/.origin
> +     @# empty recipe to enforce dependency to archive extraction
> +
> +$(LIBLUA_BUILD)/include/%.h: $(LIBLUA_SRCS_BASE)/%.h
> +     $(call build_cmd,LN,liblua,$@,\
> +     ln -sf $< $@)
> +
> +$(LIBLUA_SRCS_BASE)/%.hpp: $(LIBLUA_BUILD)/.origin
> +     @# empty recipe to enforce dependency to archive extraction
> +
> +$(LIBLUA_BUILD)/include/%.hpp: $(LIBLUA_SRCS_BASE)/%.hpp
> +     $(call build_cmd,LN,liblua,$@,\
> +     ln -sf $< $@)
> +
> +# TO_INC
> +UK_PREPARE += $(LIBLUA_BUILD)/include/lua.h
> +UK_PREPARE += $(LIBLUA_BUILD)/include/luaconf.h
> +UK_PREPARE += $(LIBLUA_BUILD)/include/lualib.h
> +UK_PREPARE += $(LIBLUA_BUILD)/include/lauxlib.h
> +UK_PREPARE += $(LIBLUA_BUILD)/include/lua.hpp
> diff --git a/lua.c b/lua.c
> new file mode 100644
> index 0000000..8f2f860
> --- /dev/null
> +++ b/lua.c

Looks like the standalone lua interpreter originates from
https://raw.githubusercontent.com/lua/lua/v5.3.5/lua.c
But I saw some tabs were changed into spaces, is that intentional?
IMO, it would be better if we changes less

--
Cheers,
Justin (Jia He)



> @@ -0,0 +1,620 @@
> +/*
> +** $Id: lua.c,v 1.230.1.1 2017/04/19 17:29:57 roberto Exp $
> +** Lua stand-alone interpreter
> +** See Copyright Notice in lua.h
> +*/
> +
> +#define lua_c
> +
> +#include "lprefix.h"
> +
> +
> +#include <signal.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +
> +#include "lua.h"
> +
> +#include "lauxlib.h"
> +#include "lualib.h"
> +
> +#include <uk/plat/memory.h>
> +
> +#if !defined(LUA_PROMPT)
> +#define LUA_PROMPT           "> "
> +#define LUA_PROMPT2          ">> "
> +#endif
> +
> +#if !defined(LUA_PROGNAME)
> +#define LUA_PROGNAME         "lua"
> +#endif
> +
> +#if !defined(LUA_MAXINPUT)
> +#define LUA_MAXINPUT         512
> +#endif
> +
> +#if !defined(LUA_INIT_VAR)
> +#define LUA_INIT_VAR         "LUA_INIT"
> +#endif
> +
> +#define LUA_INITVARVERSION   LUA_INIT_VAR LUA_VERSUFFIX
> +
> +
> +/*
> +** lua_stdin_is_tty detects whether the standard input is a 'tty' (that
> +** is, whether we're running lua interactively).
> +*/
> +#if !defined(lua_stdin_is_tty)       /* { */
> +
> +#if defined(LUA_USE_POSIX)   /* { */
> +
> +#include <unistd.h>
> +#define lua_stdin_is_tty()   isatty(0)
> +
> +#elif defined(LUA_USE_WINDOWS)       /* }{ */
> +
> +#include <io.h>
> +#include <windows.h>
> +
> +#define lua_stdin_is_tty()   _isatty(_fileno(stdin))
> +
> +#else                                /* }{ */
> +
> +/* ISO C definition */
> +#define lua_stdin_is_tty()   1  /* assume stdin is a tty */
> +
> +#endif                               /* } */
> +
> +#endif                               /* } */
> +
> +
> +/*
> +** lua_readline defines how to show a prompt and then read a line from
> +** the standard input.
> +** lua_saveline defines how to "save" a read line in a "history".
> +** lua_freeline defines how to free a line read by lua_readline.
> +*/
> +#if !defined(lua_readline)   /* { */
> +
> +#if defined(LUA_USE_READLINE)        /* { */
> +
> +#include <readline/readline.h>
> +#include <readline/history.h>
> +#define lua_readline(L,b,p)  ((void)L, ((b)=readline(p)) != NULL)
> +#define lua_saveline(L,line) ((void)L, add_history(line))
> +#define lua_freeline(L,b)    ((void)L, free(b))
> +
> +#else                                /* }{ */
> +
> +#define lua_readline(L,b,p) \
> +        ((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
> +        fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
> +#define lua_saveline(L,line) { (void)L; (void)line; }
> +#define lua_freeline(L,b)    { (void)L; (void)b; }
> +
> +#endif                               /* } */
> +
> +#endif                               /* } */
> +
> +
> +
> +
> +static lua_State *globalL = NULL;
> +
> +static const char *progname = LUA_PROGNAME;
> +
> +
> +/*
> +** Hook set by signal function to stop the interpreter.
> +*/
> +static void lstop (lua_State *L, lua_Debug *ar) {
> +  (void)ar;  /* unused arg. */
> +  lua_sethook(L, NULL, 0, 0);  /* reset hook */
> +  luaL_error(L, "interrupted!");
> +}
> +
> +
> +/*
> +** Function to be called at a C signal. Because a C signal cannot
> +** just change a Lua state (as there is no proper synchronization),
> +** this function only sets a hook that, when called, will stop the
> +** interpreter.
> +*/
> +static void laction (int i) {
> +  signal(i, SIG_DFL); /* if another SIGINT happens, terminate process */
> +  lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET |
> LUA_MASKCOUNT, 1);
> +}
> +
> +
> +static void print_usage (const char *badoption) {
> +  lua_writestringerror("%s: ", progname);
> +  if (badoption[1] == 'e' || badoption[1] == 'l')
> +    lua_writestringerror("'%s' needs argument\n", badoption);
> +  else
> +    lua_writestringerror("unrecognized option '%s'\n", badoption);
> +  lua_writestringerror(
> +  "usage: %s [options] [script [args]]\n"
> +  "Available options are:\n"
> +  "  -e stat  execute string 'stat'\n"
> +  "  -i       enter interactive mode after executing 'script'\n"
> +  "  -l name  require library 'name' into global 'name'\n"
> +  "  -v       show version information\n"
> +  "  -E       ignore environment variables\n"
> +  "  --       stop handling options\n"
> +  "  -        stop handling options and execute stdin\n"
> +  ,
> +  progname);
> +}
> +
> +
> +/*
> +** Prints an error message, adding the program name in front of it
> +** (if present)
> +*/
> +static void l_message (const char *pname, const char *msg) {
> +  if (pname) lua_writestringerror("%s: ", pname);
> +  lua_writestringerror("%s\n", msg);
> +}
> +
> +
> +/*
> +** Check whether 'status' is not OK and, if so, prints the error
> +** message on the top of the stack. It assumes that the error object
> +** is a string, as it was either generated by Lua or by 'msghandler'.
> +*/
> +static int report (lua_State *L, int status) {
> +  if (status != LUA_OK) {
> +    const char *msg = lua_tostring(L, -1);
> +    l_message(progname, msg);
> +    lua_pop(L, 1);  /* remove message */
> +  }
> +  return status;
> +}
> +
> +
> +/*
> +** Message handler used to run all chunks
> +*/
> +static int msghandler (lua_State *L) {
> +  const char *msg = lua_tostring(L, 1);
> +  if (msg == NULL) {  /* is error object not a string? */
> +    if (luaL_callmeta(L, 1, "__tostring") &&  /* does it have a metamethod
> */
> +        lua_type(L, -1) == LUA_TSTRING)  /* that produces a string? */
> +      return 1;  /* that is the message */
> +    else
> +      msg = lua_pushfstring(L, "(error object is a %s value)",
> +                               luaL_typename(L, 1));
> +  }
> +  luaL_traceback(L, L, msg, 1);  /* append a standard traceback */
> +  return 1;  /* return the traceback */
> +}
> +
> +
> +/*
> +** Interface to 'lua_pcall', which sets appropriate message function
> +** and C-signal handler. Used to run all chunks.
> +*/
> +static int docall (lua_State *L, int narg, int nres) {
> +  int status;
> +  int base = lua_gettop(L) - narg;  /* function index */
> +  lua_pushcfunction(L, msghandler);  /* push message handler */
> +  lua_insert(L, base);  /* put it under function and args */
> +  globalL = L;  /* to be available to 'laction' */
> +  signal(SIGINT, laction);  /* set C-signal handler */
> +  status = lua_pcall(L, narg, nres, base);
> +  signal(SIGINT, SIG_DFL); /* reset C-signal handler */
> +  lua_remove(L, base);  /* remove message handler from the stack */
> +  return status;
> +}
> +
> +
> +static void print_version (void) {
> +  lua_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT));
> +  lua_writeline();
> +}
> +
> +
> +/*
> +** Create the 'arg' table, which stores all arguments from the
> +** command line ('argv'). It should be aligned so that, at index 0,
> +** it has 'argv[script]', which is the script name. The arguments
> +** to the script (everything after 'script') go to positive indices;
> +** other arguments (before the script name) go to negative indices.
> +** If there is no script name, assume interpreter's name as base.
> +*/
> +static void createargtable (lua_State *L, char **argv, int argc, int script) 
> {
> +  int i, narg;
> +  if (script == argc) script = 0;  /* no script name? */
> +  narg = argc - (script + 1);  /* number of positive indices */
> +  lua_createtable(L, narg, script + 1);
> +  for (i = 0; i < argc; i++) {
> +    lua_pushstring(L, argv[i]);
> +    lua_rawseti(L, -2, i - script);
> +  }
> +  lua_setglobal(L, "arg");
> +}
> +
> +
> +static int dochunk (lua_State *L, int status) {
> +  if (status == LUA_OK) status = docall(L, 0, 0);
> +  return report(L, status);
> +}
> +
> +
> +static int dofile (lua_State *L, const char *name) {
> +  return dochunk(L, luaL_loadfile(L, name));
> +}
> +
> +
> +static int dostring (lua_State *L, const char *s, const char *name) {
> +  return dochunk(L, luaL_loadbuffer(L, s, strlen(s), name));
> +}
> +
> +
> +/*
> +** Calls 'require(name)' and stores the result in a global variable
> +** with the given name.
> +*/
> +static int dolibrary (lua_State *L, const char *name) {
> +  int status;
> +  lua_getglobal(L, "require");
> +  lua_pushstring(L, name);
> +  status = docall(L, 1, 1);  /* call 'require(name)' */
> +  if (status == LUA_OK)
> +    lua_setglobal(L, name);  /* global[name] = require return */
> +  return report(L, status);
> +}
> +
> +
> +/*
> +** Returns the string to be used as a prompt by the interpreter.
> +*/
> +static const char *get_prompt (lua_State *L, int firstline) {
> +  const char *p;
> +  lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2");
> +  p = lua_tostring(L, -1);
> +  if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2);
> +  return p;
> +}
> +
> +/* mark in error messages for incomplete statements */
> +#define EOFMARK              "<eof>"
> +#define marklen              (sizeof(EOFMARK)/sizeof(char) - 1)
> +
> +
> +/*
> +** Check whether 'status' signals a syntax error and the error
> +** message at the top of the stack ends with the above mark for
> +** incomplete statements.
> +*/
> +static int incomplete (lua_State *L, int status) {
> +  if (status == LUA_ERRSYNTAX) {
> +    size_t lmsg;
> +    const char *msg = lua_tolstring(L, -1, &lmsg);
> +    if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) {
> +      lua_pop(L, 1);
> +      return 1;
> +    }
> +  }
> +  return 0;  /* else... */
> +}
> +
> +
> +/*
> +** Prompt the user, read a line, and push it into the Lua stack.
> +*/
> +static int pushline (lua_State *L, int firstline) {
> +  char buffer[LUA_MAXINPUT];
> +  char *b = buffer;
> +  size_t l;
> +  const char *prmt = get_prompt(L, firstline);
> +  int readstatus = lua_readline(L, b, prmt);
> +  if (readstatus == 0)
> +    return 0;  /* no input (prompt will be popped by caller) */
> +  lua_pop(L, 1);  /* remove prompt */
> +  l = strlen(b);
> +  if (l > 0 && b[l-1] == '\n')  /* line ends with newline? */
> +    b[--l] = '\0';  /* remove it */
> +  if (firstline && b[0] == '=')  /* for compatibility with 5.2, ... */
> +    lua_pushfstring(L, "return %s", b + 1);  /* change '=' to 'return' */
> +  else
> +    lua_pushlstring(L, b, l);
> +  lua_freeline(L, b);
> +  return 1;
> +}
> +
> +
> +/*
> +** Try to compile line on the stack as 'return <line>;'; on return, stack
> +** has either compiled chunk or original line (if compilation failed).
> +*/
> +static int addreturn (lua_State *L) {
> +  const char *line = lua_tostring(L, -1);  /* original line */
> +  const char *retline = lua_pushfstring(L, "return %s;", line);
> +  int status = luaL_loadbuffer(L, retline, strlen(retline), "=stdin");
> +  if (status == LUA_OK) {
> +    lua_remove(L, -2);  /* remove modified line */
> +    if (line[0] != '\0')  /* non empty? */
> +      lua_saveline(L, line);  /* keep history */
> +  }
> +  else
> +    lua_pop(L, 2);  /* pop result from 'luaL_loadbuffer' and modified line */
> +  return status;
> +}
> +
> +
> +/*
> +** Read multiple lines until a complete Lua statement
> +*/
> +static int multiline (lua_State *L) {
> +  for (;;) {  /* repeat until gets a complete statement */
> +    size_t len;
> +    const char *line = lua_tolstring(L, 1, &len);  /* get what it has */
> +    int status = luaL_loadbuffer(L, line, len, "=stdin");  /* try it */
> +    if (!incomplete(L, status) || !pushline(L, 0)) {
> +      lua_saveline(L, line);  /* keep history */
> +      return status;  /* cannot or should not try to add continuation line */
> +    }
> +    lua_pushliteral(L, "\n");  /* add newline... */
> +    lua_insert(L, -2);  /* ...between the two lines */
> +    lua_concat(L, 3);  /* join them */
> +  }
> +}
> +
> +
> +/*
> +** Read a line and try to load (compile) it first as an expression (by
> +** adding "return " in front of it) and second as a statement. Return
> +** the final status of load/call with the resulting function (if any)
> +** in the top of the stack.
> +*/
> +static int loadline (lua_State *L) {
> +  int status;
> +  lua_settop(L, 0);
> +  if (!pushline(L, 1))
> +    return -1;  /* no input */
> +  if ((status = addreturn(L)) != LUA_OK)  /* 'return ...' did not work? */
> +    status = multiline(L);  /* try as command, maybe with continuation lines
> */
> +  lua_remove(L, 1);  /* remove line from the stack */
> +  lua_assert(lua_gettop(L) == 1);
> +  return status;
> +}
> +
> +
> +/*
> +** Prints (calling the Lua 'print' function) any values on the stack
> +*/
> +static void l_print (lua_State *L) {
> +  int n = lua_gettop(L);
> +  if (n > 0) {  /* any result to be printed? */
> +    luaL_checkstack(L, LUA_MINSTACK, "too many results to print");
> +    lua_getglobal(L, "print");
> +    lua_insert(L, 1);
> +    if (lua_pcall(L, n, 0, 0) != LUA_OK)
> +      l_message(progname, lua_pushfstring(L, "error calling 'print' (%s)",
> +                                             lua_tostring(L, -1)));
> +  }
> +}
> +
> +
> +/*
> +** Do the REPL: repeatedly read (load) a line, evaluate (call) it, and
> +** print any results.
> +*/
> +static void doREPL (lua_State *L) {
> +  int status;
> +  const char *oldprogname = progname;
> +  progname = NULL;  /* no 'progname' on errors in interactive mode */
> +  while ((status = loadline(L)) != -1) {
> +    if (status == LUA_OK)
> +      status = docall(L, 0, LUA_MULTRET);
> +    if (status == LUA_OK) l_print(L);
> +    else report(L, status);
> +  }
> +  lua_settop(L, 0);  /* clear stack */
> +  lua_writeline();
> +  progname = oldprogname;
> +}
> +
> +
> +/*
> +** Push on the stack the contents of table 'arg' from 1 to #arg
> +*/
> +static int pushargs (lua_State *L) {
> +  int i, n;
> +  if (lua_getglobal(L, "arg") != LUA_TTABLE)
> +    luaL_error(L, "'arg' is not a table");
> +  n = (int)luaL_len(L, -1);
> +  luaL_checkstack(L, n + 3, "too many arguments to script");
> +  for (i = 1; i <= n; i++)
> +    lua_rawgeti(L, -i, i);
> +  lua_remove(L, -i);  /* remove table from the stack */
> +  return n;
> +}
> +
> +
> +static int handle_script (lua_State *L, char **argv) {
> +  int status;
> +  const char *fname = argv[0];
> +  if (strcmp(fname, "-") == 0 && strcmp(argv[-1], "--") != 0)
> +    fname = NULL;  /* stdin */
> +  status = luaL_loadfile(L, fname);
> +  if (status == LUA_OK) {
> +    int n = pushargs(L);  /* push arguments to script */
> +    status = docall(L, n, LUA_MULTRET);
> +  }
> +  return report(L, status);
> +}
> +
> +
> +
> +/* bits of various argument indicators in 'args' */
> +#define has_error    1       /* bad option */
> +#define has_i                2       /* -i */
> +#define has_v                4       /* -v */
> +#define has_e                8       /* -e */
> +#define has_E                16      /* -E */
> +
> +/*
> +** Traverses all arguments from 'argv', returning a mask with those
> +** needed before running any Lua code (or an error code if it finds
> +** any invalid argument). 'first' returns the first not-handled argument
> +** (either the script name or a bad argument in case of error).
> +*/
> +static int collectargs (char **argv, int *first) {
> +  int args = 0;
> +  int i;
> +  for (i = 1; argv[i] != NULL; i++) {
> +    *first = i;
> +    if (argv[i][0] != '-')  /* not an option? */
> +        return args;  /* stop handling options */
> +    switch (argv[i][1]) {  /* else check option */
> +      case '-':  /* '--' */
> +        if (argv[i][2] != '\0')  /* extra characters after '--'? */
> +          return has_error;  /* invalid option */
> +        *first = i + 1;
> +        return args;
> +      case '\0':  /* '-' */
> +        return args;  /* script "name" is '-' */
> +      case 'E':
> +        if (argv[i][2] != '\0')  /* extra characters after 1st? */
> +          return has_error;  /* invalid option */
> +        args |= has_E;
> +        break;
> +      case 'i':
> +        args |= has_i;  /* (-i implies -v) *//* FALLTHROUGH */
> +      case 'v':
> +        if (argv[i][2] != '\0')  /* extra characters after 1st? */
> +          return has_error;  /* invalid option */
> +        args |= has_v;
> +        break;
> +      case 'e':
> +        args |= has_e;  /* FALLTHROUGH */
> +      case 'l':  /* both options need an argument */
> +        if (argv[i][2] == '\0') {  /* no concatenated argument? */
> +          i++;  /* try next 'argv' */
> +          if (argv[i] == NULL || argv[i][0] == '-')
> +            return has_error;  /* no next argument or it is another option */
> +        }
> +        break;
> +      default:  /* invalid option */
> +        return has_error;
> +    }
> +  }
> +  *first = i;  /* no script name */
> +  return args;
> +}
> +
> +
> +/*
> +** Processes options 'e' and 'l', which involve running Lua code.
> +** Returns 0 if some code raises an error.
> +*/
> +static int runargs (lua_State *L, char **argv, int n) {
> +  int i;
> +  for (i = 1; i < n; i++) {
> +    int option = argv[i][1];
> +    lua_assert(argv[i][0] == '-');  /* already checked */
> +    if (option == 'e' || option == 'l') {
> +      int status;
> +      const char *extra = argv[i] + 2;  /* both options need an argument */
> +      if (*extra == '\0') extra = argv[++i];
> +      lua_assert(extra != NULL);
> +      status = (option == 'e')
> +               ? dostring(L, extra, "=(command line)")
> +               : dolibrary(L, extra);
> +      if (status != LUA_OK) return 0;
> +    }
> +  }
> +  return 1;
> +}
> +
> +
> +
> +static int handle_luainit (lua_State *L) {
> +  const char *name = "=" LUA_INITVARVERSION;
> +  const char *init = getenv(name + 1);
> +  if (init == NULL) {
> +    name = "=" LUA_INIT_VAR;
> +    init = getenv(name + 1);  /* try alternative name */
> +  }
> +  if (init == NULL) return LUA_OK;
> +  else if (init[0] == '@')
> +    return dofile(L, init+1);
> +  else
> +    return dostring(L, init, name);
> +}
> +
> +
> +/*
> +** Main body of stand-alone interpreter (to be called in protected mode).
> +** Reads the options and handles them all.
> +*/
> +static int pmain (lua_State *L) {
> +  int argc = (int)lua_tointeger(L, 1);
> +  char **argv = (char **)lua_touserdata(L, 2);
> +  int script;
> +  struct ukplat_memregion_desc img;
> +  char *cstr;
> +
> +  int args = collectargs(argv, &script);
> +  luaL_checkversion(L);  /* check that interpreter has correct version */
> +  if (argv[0] && argv[0][0]) progname = argv[0];
> +  if (args == has_error) {  /* bad arg? */
> +    print_usage(argv[script]);  /* 'script' has index of bad arg. */
> +    return 0;
> +  }
> +  if (args & has_v)  /* option '-v'? */
> +    print_version();
> +  if (args & has_E) {  /* option '-E'? */
> +    lua_pushboolean(L, 1);  /* signal for libraries to ignore env. vars. */
> +    lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
> +  }
> +  luaL_openlibs(L);  /* open standard libraries */
> +  createargtable(L, argv, argc, script);  /* create table 'arg' */
> +  if (!(args & has_E)) {  /* no option '-E'? */
> +    if (handle_luainit(L) != LUA_OK)  /* run LUA_INIT */
> +      return 0;  /* error running LUA_INIT */
> +  }
> +  if (!runargs(L, argv, script))  /* execute arguments -e and -l */
> +    return 0;  /* something failed */
> +  if (script < argc &&  /* execute main script (if there is one) */
> +      handle_script(L, argv + script) != LUA_OK)
> +    return 0;
> +  if (args & has_i)  /* -i option? */
> +    doREPL(L);  /* do read-eval-print loop */
> +  /* see if script is available from initrd */
> +  else if (ukplat_memregion_find_initrd0(&img) >= 0) {
> +    cstr = (char *)img.base;
> +    dostring(L, cstr, "initrd");
> +  }
> +  else if (script == argc && !(args & (has_e | has_v))) {  /* no arguments?
> */
> +    if (lua_stdin_is_tty()) {  /* running in interactive mode? */
> +      print_version();
> +      doREPL(L);  /* do read-eval-print loop */
> +    }
> +    else dofile(L, NULL);  /* executes stdin as a file */
> +  }
> +  lua_pushboolean(L, 1);  /* signal no errors */
> +  return 1;
> +}
> +
> +
> +int lua_main (int argc, char **argv) {
> +  int status, result;
> +  lua_State *L = luaL_newstate();  /* create state */
> +  if (L == NULL) {
> +    l_message(argv[0], "cannot create state: not enough memory");
> +    return EXIT_FAILURE;
> +  }
> +  lua_pushcfunction(L, &pmain);  /* to call 'pmain' in protected mode */
> +  lua_pushinteger(L, argc);  /* 1st argument */
> +  lua_pushlightuserdata(L, argv); /* 2nd argument */
> +  status = lua_pcall(L, 2, 1, 0);  /* do the call */
> +  result = lua_toboolean(L, -1);  /* get result */
> +  report(L, status);
> +  lua_close(L);
> +  return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE;
> +}
> +
> --
> 2.11.0
>
>
> _______________________________________________
> Minios-devel mailing list
> Minios-devel@xxxxxxxxxxxxxxxxxxxx
> https://lists.xenproject.org/mailman/listinfo/minios-devel
IMPORTANT NOTICE: The contents of this email and any attachments are 
confidential and may also be privileged. If you are not the intended recipient, 
please notify the sender immediately and do not disclose the contents to any 
other person, use it for any purpose, or store or copy the information in any 
medium. Thank you.
_______________________________________________
Minios-devel mailing list
Minios-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/minios-devel