hush: next small step towards functions
diff --git a/shell/hush.c b/shell/hush.c
index 377f13a..6efc307 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -96,6 +96,12 @@
#endif
+/* Keep unconditionally on for now */
+#define HUSH_DEBUG 1
+/* In progress... */
+#define ENABLE_HUSH_FUNCTIONS 0
+
+
/* If you comment out one of these below, it will be #defined later
* to perform debug printfs to stderr: */
#define debug_printf(...) do {} while (0)
@@ -218,8 +224,6 @@
#endif
-/* Keep unconditionally on for now */
-#define HUSH_DEBUG 1
/* Do we support ANY keywords? */
#if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
#define HAS_KEYWORDS 1
@@ -307,7 +311,7 @@
pid_t pid; /* 0 if exited */
int assignment_cnt; /* how many argv[i] are assignments? */
smallint is_stopped; /* is the command currently running? */
- smallint subshell; /* flag, non-zero if group must be forked */
+ smallint grp_type;
struct pipe *group; /* if non-NULL, this "prog" is {} group,
* subshell, or a compound statement */
char **argv; /* command name and arguments */
@@ -319,6 +323,11 @@
* Example: argv[0]=='.^C*^C.' here: echo .$*.
* References of the form ^C`cmd arg^C are `cmd arg` substitutions.
*/
+#define GRP_NORMAL 0
+#define GRP_SUBSHELL 1
+#if ENABLE_HUSH_FUNCTIONS
+#define GRP_FUNCTION 2
+#endif
struct pipe {
struct pipe *next;
@@ -1016,12 +1025,14 @@
static void o_addqchr(o_string *o, int ch)
{
int sz = 1;
- if (strchr("*?[\\", ch)) {
+ char *found = strchr("*?[\\", ch);
+ if (found)
sz++;
+ o_grow_by(o, sz);
+ if (found) {
o->data[o->length] = '\\';
o->length++;
}
- o_grow_by(o, sz);
o->data[o->length] = ch;
o->length++;
o->data[o->length] = '\0';
@@ -1834,7 +1845,15 @@
*/
command = &(pi->cmds[0]);
- if (single_and_fg && command->group && command->subshell == 0) {
+#if ENABLE_HUSH_FUNCTIONS
+ if (single_and_fg && command->group && command->grp_type == GRP_FUNCTION) {
+ /* We "execute" function definition */
+ bb_error_msg("here we ought to remember function definition, and go on");
+ return EXIT_SUCCESS;
+ }
+#endif
+
+ if (single_and_fg && command->group && command->grp_type == GRP_NORMAL) {
debug_printf("non-subshell grouping\n");
setup_redirects(command, squirrel);
debug_printf_exec(": run_list\n");
@@ -2023,7 +2042,7 @@
#ifndef debug_print_tree
static void debug_print_tree(struct pipe *pi, int lvl)
{
- static const char *PIPE[] = {
+ static const char *const PIPE[] = {
[PIPE_SEQ] = "SEQ",
[PIPE_AND] = "AND",
[PIPE_OR ] = "OR" ,
@@ -2057,6 +2076,13 @@
[RES_XXXX ] = "XXXX" ,
[RES_SNTX ] = "SNTX" ,
};
+ static const char *const GRPTYPE[] = {
+ "()",
+ "{}",
+#if ENABLE_HUSH_FUNCTIONS
+ "func()",
+#endif
+ };
int pin, prn;
@@ -2072,7 +2098,7 @@
fprintf(stderr, "%*s prog %d assignment_cnt:%d", lvl*2, "", prn, command->assignment_cnt);
if (command->group) {
fprintf(stderr, " group %s: (argv=%p)\n",
- (command->subshell ? "()" : "{}"),
+ GRPTYPE[command->grp_type],
argv);
debug_print_tree(command->group, lvl+1);
prn++;
@@ -2443,7 +2469,7 @@
free_strings(command->argv);
command->argv = NULL;
} else if (command->group) {
- debug_printf_clean("%s begin group (subshell:%d)\n", indenter(indent), command->subshell);
+ debug_printf_clean("%s begin group (grp_type:%d)\n", indenter(indent), command->grp_type);
ret_code = free_pipe_list(command->group, indent+3);
debug_printf_clean("%s end group\n", indenter(indent));
} else {
@@ -2572,7 +2598,6 @@
#if ENABLE_HUSH_TICK
o_string subst_result = NULL_O_STRING;
#endif
-
o_addstr(output, arg, p - arg);
debug_print_list("expand_vars_to_list[1]", output, n);
arg = ++p;
@@ -3100,7 +3125,7 @@
done_pipe(ctx, PIPE_SEQ);
old = ctx->stack;
old->command->group = ctx->list_head;
- old->command->subshell = 0;
+ old->command->grp_type = GRP_NORMAL;
*ctx = *old; /* physical copy */
free(old);
}
@@ -3461,15 +3486,24 @@
static int parse_group(o_string *dest, struct parse_context *ctx,
struct in_str *input, int ch)
{
- /* NB: parse_group may create and use its own o_string,
- * without any code changes. It just so happens that code is smaller
- * if we (ab)use caller's one. */
+ /* dest contains characters seen prior to ( or {.
+ * Typically it's empty, but for functions defs,
+ * it contains function name (without '()'). */
int rcode;
const char *endch = NULL;
struct parse_context sub;
struct command *command = ctx->command;
debug_printf_parse("parse_group entered\n");
+#if ENABLE_HUSH_FUNCTIONS
+ if (ch == 'F') { /* function definition? */
+ bb_error_msg("aha '%s' is a function, parsing it...", dest->data);
+ //command->fname = dest->data;
+ command->grp_type = GRP_FUNCTION;
+//TODO: review every o_reset() location... do they handle all o_string fields correctly?
+ memset(dest, 0, sizeof(*dest));
+ }
+#endif
if (command->argv /* word [word](... */
|| dest->length /* word(... */
|| dest->nonnull /* ""(... */
@@ -3482,11 +3516,8 @@
endch = "}";
if (ch == '(') {
endch = ")";
- command->subshell = 1;
+ command->grp_type = GRP_SUBSHELL;
}
-//TODO if (ch == 'F') { /* function definition */
-// command->subshell = 2;
-// }
rcode = parse_stream(dest, &sub, input, endch);
if (rcode == 0) {
done_word(dest, &sub); /* finish off the final word in the subcontext */
@@ -3988,16 +4019,18 @@
continue;
}
#endif
-#if 0 /* TODO: implement functions */
+#if ENABLE_HUSH_FUNCTIONS
if (dest->length != 0 /* not just () but word() */
&& dest->nonnull == 0 /* not a"b"c() */
&& ctx->command->argv == NULL /* it's the first word */
+//TODO: "func ( ) {...}" - note spaces - is valid format too in bash
&& i_peek(input) == ')'
&& !match_reserved_word(dest)
) {
bb_error_msg("seems like a function definition");
i_getch(input);
do {
+//TODO: do it properly.
ch = i_getch(input);
} while (ch == ' ' || ch == '\n');
if (ch != '{') {
@@ -4005,6 +4038,7 @@
debug_printf_parse("parse_stream return 1\n");
return 1;
}
+ ch = 'F'; /* magic value */
}
#endif
case '{':
