Bug: lua.c assumes that argv has at least one element
diff --git a/lua.c b/lua.c
index 0f19004..7f7dc2b 100644
--- a/lua.c
+++ b/lua.c
@@ -177,10 +177,11 @@
** 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.
+** (If there is no interpreter's name either, 'script' is -1, so
+** table sizes are zero.)
*/
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++) {
@@ -268,14 +269,23 @@
/*
** 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).
+** needed before running any Lua code or an error code if it finds any
+** invalid argument. In case of error, 'first' is the index of the bad
+** argument. Otherwise, 'first' is -1 if there is no program name,
+** 0 if there is no script name, or the index of the script name.
*/
static int collectargs (char **argv, int *first) {
int args = 0;
int i;
- for (i = 1; argv[i] != NULL; i++) {
+ if (argv[0] != NULL) { /* is there a program name? */
+ if (argv[0][0]) /* not empty? */
+ progname = argv[0]; /* save it */
+ }
+ else { /* no program name */
+ *first = -1;
+ return 0;
+ }
+ for (i = 1; argv[i] != NULL; i++) { /* handle arguments */
*first = i;
if (argv[i][0] != '-') /* not an option? */
return args; /* stop handling options */
@@ -316,7 +326,7 @@
return has_error;
}
}
- *first = i; /* no script name */
+ *first = 0; /* no script name */
return args;
}
@@ -609,8 +619,8 @@
char **argv = (char **)lua_touserdata(L, 2);
int script;
int args = collectargs(argv, &script);
+ int optlim = (script > 0) ? script : argc; /* first argv not an option */
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;
@@ -628,14 +638,15 @@
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 */
+ if (!runargs(L, argv, optlim)) /* 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 (script > 0) { /* execute main script (if there is one) */
+ if (handle_script(L, argv + script) != LUA_OK)
+ return 0; /* interrupt in case of error */
+ }
if (args & has_i) /* -i option? */
doREPL(L); /* do read-eval-print loop */
- else if (script == argc && !(args & (has_e | has_v))) { /* no arguments? */
+ else if (script < 1 && !(args & (has_e | has_v))) { /* no active option? */
if (lua_stdin_is_tty()) { /* running in interactive mode? */
print_version();
doREPL(L); /* do read-eval-print loop */
