General cleanup

Memory allocation errors seem to be handled now.
This commit is contained in:
Přemysl Eric Janouch 2017-05-20 15:38:06 +02:00
parent 3c86249f11
commit 23da396614
Signed by: p
GPG Key ID: B715679E3A361BE6
1 changed files with 86 additions and 107 deletions

193
ell.c
View File

@ -160,8 +160,8 @@ new_clone (const struct item *item) {
return NULL;
memcpy (clone, item, size);
if (item->type == ITEM_LIST) {
if (clone->head && !(clone->head = new_clone_list (clone->head))) {
if (item->type == ITEM_LIST && clone->head) {
if (!(clone->head = new_clone_list (clone->head))) {
free (clone);
return NULL;
}
@ -475,8 +475,7 @@ parser_peek (struct parser *self, jmp_buf out) {
!(self->error = lexer_errorf (&self->lexer, "%s", e));
longjmp (out, 1);
}
if (self->token == T_STRING
&& (self->memory_failure = self->lexer.string.memory_failure))
if (self->token == T_STRING && self->lexer.string.memory_failure)
longjmp (out, 1);
self->replace_token = false;
}
@ -615,11 +614,9 @@ parser_run (struct parser *self, const char **e) {
struct item *volatile result = NULL, *volatile *tail = &result;
if (setjmp (err)) {
item_free_list (result);
if (e) {
*e = self->error;
if (self->memory_failure)
*e = "memory allocation failure";
}
*e = self->error;
if (self->memory_failure || self->lexer.string.memory_failure)
*e = "memory allocation failure";
return NULL;
}
@ -667,9 +664,6 @@ native_register (const char *name, handler_fn handler) {
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// TODO: fill in "error_is_fatal"
// TODO: probably add new_*() methods that set "memory_failure"
struct context {
struct item *variables; ///< List of variables
@ -691,6 +685,11 @@ context_free (struct context *ctx) {
free (ctx->error);
}
static bool
check (struct context *ctx, struct item *item) {
return !(ctx->memory_failure |= !item);
}
static struct item *
get (struct context *ctx, const char *name) {
for (struct item *iter = ctx->variables; iter; iter = iter->next)
@ -701,49 +700,36 @@ get (struct context *ctx, const char *name) {
static bool
set (struct context *ctx, const char *name, struct item *value) {
struct item *iter, *key = NULL, *pair = NULL;
struct item *iter, *key, *pair;
for (iter = ctx->variables; iter; iter = iter->next)
if (!strcmp (iter->head->value, name))
break;
if (iter) {
item_free (iter->head->next);
if (!(iter->head->next = new_clone (value))) {
ctx->memory_failure = true;
return false;
}
return true;
return check (ctx, (iter->head->next = new_clone (value)));
}
if ((key = new_string (name, strlen (name)))
&& (pair = new_list (NULL))) {
if (!((pair->head = key)->next = new_clone (value))) {
item_free (pair);
ctx->memory_failure = true;
return false;
}
pair->next = ctx->variables;
ctx->variables = pair;
return true;
} else {
item_free_list (key);
item_free_list (pair);
ctx->memory_failure = true;
if (!check (ctx, (key = new_string (name, strlen (name))))
|| !check (ctx, (pair = new_list (key))))
return false;
if (!check (ctx, (key->next = new_clone (value)))) {
item_free (pair);
return false;
}
pair->next = ctx->variables;
ctx->variables = pair;
return true;
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
static bool
set_error (struct context *ctx, const char *format, ...) {
free (ctx->error);
va_list ap;
va_start (ap, format);
ctx->error = vformat (format, ap);
va_end (ap);
if (!ctx->error)
free (ctx->error);
if (!(ctx->error = vformat (format, ap)))
ctx->memory_failure = true;
va_end (ap);
return false;
}
@ -760,7 +746,7 @@ rename_arguments (struct context *ctx, struct item *names) {
return true;
if (names->type != ITEM_STRING)
continue;
return set_error (ctx, "argument names must be strings");
if (!set (ctx, names->value, value))
return false;
}
@ -771,44 +757,33 @@ static bool execute_statement (struct context *, struct item *, struct item **);
static bool execute (struct context *ctx, struct item *body, struct item **);
static bool
execute_args_list (struct context *ctx, struct item *args, struct item **res) {
for (struct item *arg = args; arg; arg = arg->next) {
execute_args (struct context *ctx, struct item *args, struct item **res) {
for (; args; args = args->next) {
struct item *evaluated = NULL;
if (!execute_statement (ctx, arg, &evaluated))
if (!execute_statement (ctx, args, &evaluated))
return false;
if (evaluated) {
item_free_list (evaluated->next);
evaluated->next = NULL;
*res = evaluated;
res = &evaluated->next;
res = &(*res = evaluated)->next;
}
}
return true;
}
static bool
execute_native (struct context *ctx,
struct native_fn *fn, struct item *next, struct item **res) {
struct item *args = NULL;
bool ok = execute_args_list (ctx, next, &args)
&& fn->handler (ctx, args, res);
item_free_list (args);
return ok;
}
// TODO: we should probably maintain arguments in a separate list,
// either that or at least remember the count so that we can reset them
static bool
execute_args (struct context *ctx, struct item *next) {
execute_args_and_set (struct context *ctx, struct item *following) {
struct item *args = NULL;
if (!execute_args_list (ctx, next, &args)) {
if (!execute_args (ctx, following, &args)) {
item_free_list (args);
return false;
}
char buf[64];
size_t i = 0;
for (struct item *arg = args; arg; arg = arg->next) {
char buf[64];
(void) snprintf (buf, sizeof buf, "%zu", i++);
if (!set (ctx, buf, arg))
return false;
@ -817,15 +792,21 @@ execute_args (struct context *ctx, struct item *next) {
return true;
}
static bool
execute_native (struct context *ctx,
struct native_fn *fn, struct item *next, struct item **res) {
struct item *args = NULL;
bool ok = execute_args (ctx, next, &args)
&& fn->handler (ctx, args, res);
item_free_list (args);
return ok;
}
static bool
execute_statement
(struct context *ctx, struct item *statement, struct item **result) {
if (statement->type == ITEM_STRING) {
if ((*result = new_clone (statement)))
return true;
ctx->memory_failure = true;
return false;
}
if (statement->type == ITEM_STRING)
return check (ctx, (*result = new_clone (statement)));
// XXX: should this ever happen and what are the consequences?
// Shouldn't we rather clone the empty list?
@ -838,12 +819,10 @@ execute_statement
if (body->type == ITEM_STRING) {
name = body->value;
// TODO: these could be just regular handlers, only top priority
if (!strcmp (name, "quote")) {
if (!following || (*result = new_clone_list (following)))
return true;
ctx->memory_failure = true;
return false;
}
// TODO: these should also get a stack trace the normal way
if (!strcmp (name, "quote"))
return !following
|| check (ctx, (*result = new_clone_list (following)));
if (!strcmp (name, "arg"))
return rename_arguments (ctx, following);
body = get (ctx, name);
@ -857,23 +836,21 @@ execute_statement
return true;
} else if (body->type == ITEM_STRING) {
// Recursion could be pretty fatal, let's not do that
if ((*result = new_clone (body)))
if (check (ctx, (*result = new_clone (body))))
return true;
ctx->memory_failure = true;
} else {
if (execute_args (ctx, following)
if (execute_args_and_set (ctx, following)
&& execute (ctx, body->head, result))
return true;
}
// In this case, `error' is NULL
if (ctx->memory_failure)
return false;
// This creates some form of a stack trace
char *tmp = ctx->error;
set_error (ctx, "%s -> %s", name, tmp);
free (tmp);
// In that case, `error' is NULL and there's nothing else to do anyway
if (!ctx->memory_failure) {
// This creates some form of a stack trace
char *tmp = ctx->error;
set_error (ctx, "%s -> %s", name, tmp);
free (tmp);
}
return false;
}
@ -925,56 +902,59 @@ init_runtime_library_scripts (struct context *ctx) {
defn (fn_set) {
struct item *name = args;
if (!name || name->type != ITEM_STRING)
return (void *) set_error (ctx, "first argument must be string");
return set_error (ctx, "first argument must be string");
struct item *value;
if ((value = name->next))
return set (ctx, name->value, value);
// FIXME: how do we represent a nil value here?
*result = new_clone (get (ctx, name->value));
return true;
return check (ctx, (*result = new_clone (get (ctx, name->value))));
}
defn (fn_list) {
struct item *values = NULL;
if (args && !check (ctx, (values = new_clone_list (args))))
return false;
return check (ctx, (*result = new_list (values)));
}
defn (fn_print) {
(void) result;
// TODO: error on list
struct buffer buf = BUFFER_INITIALIZER;
for (; args; args = args->next)
buffer_append (&buf, args->value, args->len);
buffer_append_c (&buf, '\0');
if (buf.memory_failure) {
ctx->memory_failure = true;
return false;
for (; args; args = args->next) {
if (args->type != ITEM_STRING)
// TODO: print lists as their parsable representation
return set_error (ctx, "cannot print lists");
if (fwrite (args->value, 1, args->len, stdout) != args->len)
return set_error (ctx, "write failed: %s", strerror (errno));
}
printf ("%s", buf.s);
free (buf.s);
return true;
}
defn (fn_concatenate) {
// TODO: error on list
struct buffer buf = BUFFER_INITIALIZER;
for (; args; args = args->next)
for (; args; args = args->next) {
if (args->type != ITEM_STRING) {
free (buf.s);
return set_error (ctx, "cannot concatenate lists");
}
buffer_append (&buf, args->value, args->len);
buffer_append_c (&buf, '\0');
if (buf.memory_failure) {
ctx->memory_failure = true;
return false;
}
*result = new_string (buf.s, buf.len);
buffer_append_c (&buf, '\0');
bool ok = !(ctx->memory_failure = buf.memory_failure)
&& check (ctx, (*result = new_string (buf.s, buf.len)));
free (buf.s);
return true;
return ok;
}
static bool
init_runtime_library (void)
{
return native_register ("..", fn_concatenate)
&& native_register ("set", fn_set)
&& native_register ("print", fn_print);
return native_register ("set", fn_set)
&& native_register ("list", fn_list)
&& native_register ("print", fn_print)
&& native_register ("..", fn_concatenate);
}
static void
@ -1008,7 +988,6 @@ main (int argc, char *argv[]) {
const char *e = NULL;
struct item *program = parser_run (&parser, &e);
free (buf.s);
if (e) {
printf ("%s: %s\n", "parse error", e);
return 1;