erts: Improve enif_binary_to_term

* Accept a raw data buffer instead of ErlNifBinary
* Accept option ERL_NIF_BIN2TERM_SAFE
* Return number of read bytes

7 files changed, 43 insertions, 30 deletions

diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c
index f115df935f..d3d278fb81 100644
--- a/erts/emulator/beam/beam_load.c
+++ b/erts/emulator/beam/beam_load.c
@@ -1548,7 +1548,7 @@ read_literal_table(LoaderState* stp)
             erts_factory_heap_frag_init(&factory,
 					new_literal_fragment(heap_size));
 	    factory.alloc_type = ERTS_ALC_T_PREPARED_CODE;
-            val = erts_decode_ext(&factory, &p);
+            val = erts_decode_ext(&factory, &p, 0);
 
             if (is_non_value(val)) {
                 LoadError1(stp, "literal %d: bad external format", i);
@@ -1559,7 +1559,7 @@ read_literal_table(LoaderState* stp)
         }
         else {
             erts_factory_dummy_init(&factory);
-            val = erts_decode_ext(&factory, &p);
+            val = erts_decode_ext(&factory, &p, 0);
             if (is_non_value(val)) {
                 LoadError1(stp, "literal %d: bad external format", i);
             }
@@ -5719,7 +5719,7 @@ attributes_for_module(Process* p, /* Process whose heap to use. */
     if (ext != NULL) {
 	ErtsHeapFactory factory;
 	erts_factory_proc_prealloc_init(&factory, p, code_hdr->attr_size_on_heap);
-	result = erts_decode_ext(&factory, &ext);
+	result = erts_decode_ext(&factory, &ext, 0);
 	if (is_value(result)) {
 	    erts_factory_close(&factory);
 	}
@@ -5742,7 +5742,7 @@ compilation_info_for_module(Process* p, /* Process whose heap to use. */
     if (ext != NULL) {
 	ErtsHeapFactory factory;
 	erts_factory_proc_prealloc_init(&factory, p, code_hdr->compile_size_on_heap);
-	result = erts_decode_ext(&factory, &ext);
+	result = erts_decode_ext(&factory, &ext, 0);
 	if (is_value(result)) {
 	    erts_factory_close(&factory);
 	}
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 6ed89780b4..d8f2272c6d 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -686,17 +686,25 @@ int enif_term_to_binary(ErlNifEnv *dst_env, ERL_NIF_TERM term,
     return 1;
 }
 
-int enif_binary_to_term(ErlNifEnv *dst_env, ErlNifBinary *bin,
-                        ERL_NIF_TERM *term)
+size_t enif_binary_to_term(ErlNifEnv *dst_env,
+                           const unsigned char* data,
+                           size_t data_sz,
+                           ERL_NIF_TERM *term,
+                           ErlNifBinaryToTerm opts)
 {
     Sint size;
     ErtsHeapFactory factory;
+    byte *bp = (byte*) data;
 
-    if ((size = erts_decode_ext_size(bin->data, bin->size)) < 0)
+    ERTS_CT_ASSERT(ERL_NIF_BIN2TERM_SAFE == ERTS_DIST_EXT_BTT_SAFE);
+
+    if (opts & ~ERL_NIF_BIN2TERM_SAFE) {
+        return 0;
+    }
+    if ((size = erts_decode_ext_size(bp, data_sz)) < 0)
         return 0;
 
     if (size > 0) {
-        byte *bp;
 
         if (is_internal_pid(dst_env->proc->common.id)) {
             flush_env(dst_env);
@@ -710,25 +718,18 @@ int enif_binary_to_term(ErlNifEnv *dst_env, ErlNifBinary *bin,
 
             erts_factory_heap_frag_init(&factory, dst_env->heap_frag);
         }
+    } else {
+        erts_factory_dummy_init(&factory);
+    }
 
-        bp = bin->data;
-        *term = erts_decode_ext(&factory, &bp);
-
-        if (is_non_value(*term)) {
-            return 0;
-        }
+    *term = erts_decode_ext(&factory, &bp, (Uint32)opts);
 
-        erts_factory_close(&factory);
-    }
-    else {
-        erts_factory_dummy_init(&factory);
-        *term = erts_decode_ext(&factory, &bin->data);
-        if (is_non_value(*term)) {
-            return 0;
-        }
-        ASSERT(is_immed(*term));
+    if (is_non_value(*term)) {
+        return 0;
     }
-    return 1;
+    erts_factory_close(&factory);
+    ASSERT(bp > data);
+    return bp - data;
 }
 
 int enif_is_identical(Eterm lhs, Eterm rhs)
diff --git a/erts/emulator/beam/erl_nif.h b/erts/emulator/beam/erl_nif.h
index 6ee22a693c..bc1f59bc90 100644
--- a/erts/emulator/beam/erl_nif.h
+++ b/erts/emulator/beam/erl_nif.h
@@ -207,6 +207,10 @@ typedef enum {
     ERL_NIF_UNIQUE_MONOTONIC = (1 << 1)
 } ErlNifUniqueInteger;
 
+typedef enum {
+    ERL_NIF_BIN2TERM_SAFE = 0x20000000
+} ErlNifBinaryToTerm;
+
 #if (defined(__WIN32__) || defined(_WIN32) || defined(_WIN32_))
 #  define ERL_NIF_API_FUNC_DECL(RET_TYPE, NAME, ARGS) RET_TYPE (*NAME) ARGS
 typedef struct {
diff --git a/erts/emulator/beam/erl_nif_api_funcs.h b/erts/emulator/beam/erl_nif_api_funcs.h
index 32afb53bfc..35058afe7c 100644
--- a/erts/emulator/beam/erl_nif_api_funcs.h
+++ b/erts/emulator/beam/erl_nif_api_funcs.h
@@ -170,7 +170,7 @@ ERL_NIF_API_FUNC_DECL(int, enif_is_process_alive, (ErlNifEnv *env, ErlNifPid *pi
 ERL_NIF_API_FUNC_DECL(int, enif_is_port_alive, (ErlNifEnv *env, ErlNifPort *port_id));
 ERL_NIF_API_FUNC_DECL(int, enif_get_local_port, (ErlNifEnv* env, ERL_NIF_TERM, ErlNifPort* port_id));
 ERL_NIF_API_FUNC_DECL(int, enif_term_to_binary, (ErlNifEnv *env, ERL_NIF_TERM term, ErlNifBinary *bin));
-ERL_NIF_API_FUNC_DECL(int, enif_binary_to_term, (ErlNifEnv *env, ErlNifBinary *bin, ERL_NIF_TERM *term));
+ERL_NIF_API_FUNC_DECL(size_t, enif_binary_to_term, (ErlNifEnv *env, const unsigned char* data, size_t sz, ERL_NIF_TERM *term, unsigned int opts));
 ERL_NIF_API_FUNC_DECL(int, enif_port_command, (ErlNifEnv *env, const ErlNifPort* to_port, ErlNifEnv *msg_env, ERL_NIF_TERM msg));
 
 /*
diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index aac1490f0c..f5eb13421d 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -967,15 +967,23 @@ erts_decode_dist_ext(ErtsHeapFactory* factory,
     return THE_NON_VALUE;
 }
 
-Eterm erts_decode_ext(ErtsHeapFactory* factory, byte **ext)
+Eterm erts_decode_ext(ErtsHeapFactory* factory, byte **ext, Uint32 flags)
 {
+    ErtsDistExternal ede, *edep;
     Eterm obj;
     byte *ep = *ext;
     if (*ep++ != VERSION_MAGIC) {
         erts_factory_undo(factory);
 	return THE_NON_VALUE;
     }
-    ep = dec_term(NULL, factory, ep, &obj, NULL);
+    if (flags) {
+        ASSERT(flags == ERTS_DIST_EXT_BTT_SAFE);
+        ede.flags = flags; /* a dummy struct just for the flags */
+        edep = &ede;
+    } else {
+        edep = NULL;
+    }
+    ep = dec_term(edep, factory, ep, &obj, NULL);
     if (!ep) {
 #ifdef DEBUG
 	bin_write(ERTS_PRINT_STDERR,NULL,*ext,500);
diff --git a/erts/emulator/beam/external.h b/erts/emulator/beam/external.h
index d12051c6b4..87eff2fe9f 100644
--- a/erts/emulator/beam/external.h
+++ b/erts/emulator/beam/external.h
@@ -191,7 +191,7 @@ Eterm erts_decode_dist_ext(ErtsHeapFactory* factory, ErtsDistExternal *);
 
 Sint erts_decode_ext_size(byte*, Uint);
 Sint erts_decode_ext_size_ets(byte*, Uint);
-Eterm erts_decode_ext(ErtsHeapFactory*, byte**);
+Eterm erts_decode_ext(ErtsHeapFactory*, byte**, Uint32 flags);
 Eterm erts_decode_ext_ets(ErtsHeapFactory*, byte*);
 
 Eterm erts_term_to_binary(Process* p, Eterm Term, int level, Uint flags);
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 093334aab7..c7b21c0386 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -4570,7 +4570,7 @@ port_sig_call(Port *prt,
 
                 (void) erts_factory_message_create(&factory, rp, &rp_locks, hsz);
 		endp = (byte *) resp_bufp;
-		msg = erts_decode_ext(&factory, &endp);
+		msg = erts_decode_ext(&factory, &endp, 0);
 		if (is_value(msg)) {
                     hp = erts_produce_heap(&factory,
                                            3,
@@ -4689,7 +4689,7 @@ erts_port_call(Process* c_p,
 	    hsz += 3;
             erts_factory_proc_prealloc_init(&factory, c_p, hsz);
 	    endp = (byte *) resp_bufp;
-	    term = erts_decode_ext(&factory, &endp);
+	    term = erts_decode_ext(&factory, &endp, 0);
 	    if (term == THE_NON_VALUE)
 		return ERTS_PORT_OP_BADARG;
             hp = erts_produce_heap(&factory,3,0);