Add draft file API, doesn't work yet.

libclamav/bytecode.c

@@ -39,6 +39,8 @@ struct cli_bc_ctx *cli_bytecode_context_alloc(void)
     ctx->values = NULL;
     ctx->operands = NULL;
     ctx->opsizes = NULL;
+    ctx->fd = -1;
+    ctx->off = 0;
     return ctx;
 }
 
@@ -940,8 +942,10 @@ int cli_bytecode_load(struct cli_bc *bc, FILE *f, struct cli_dbio *dbio)
 	switch (state) {
 	    case PARSE_BC_HEADER:
 		rc = parseHeader(bc, (unsigned char*)buffer);
-		if (rc == CL_BREAK) /* skip */
+		if (rc == CL_BREAK) /* skip */ {
+		    bc->state = bc_skip;
 		    return CL_SUCCESS;
+		}
 		if (rc != CL_SUCCESS) {
 		    cli_errmsg("Error at bytecode line %u\n", row);
 		    return rc;
@@ -958,8 +962,10 @@ int cli_bytecode_load(struct cli_bc *bc, FILE *f, struct cli_dbio *dbio)
 		break;
 	    case PARSE_BC_APIS:
 		rc = parseApis(bc, (unsigned char*)buffer);
-		if (rc == CL_BREAK) /* skip */
+		if (rc == CL_BREAK) /* skip */ {
+		    bc->state = bc_skip;
 		    return CL_SUCCESS;
+		}
 		if (rc != CL_SUCCESS) {
 		    cli_errmsg("Error at bytecode line %u\n", row);
 		    return rc;

libclamav/bytecode.h

@@ -34,6 +34,7 @@ struct cli_bc_engine;
 struct bitset_tag;
 
 enum bc_state {
+    bc_skip,
     bc_loaded,
     bc_jit,
     bc_interp

libclamav/bytecode_api.c

@@ -20,7 +20,10 @@
  *  MA 02110-1301, USA.
  */
 
+#include <stdlib.h>
 #include "cltypes.h"
+#include "clambc.h"
+#include "bytecode_priv.h"
 #include "type_desc.h"
 #include "bytecode_api.h"
 #include "bytecode_api_impl.h"
@@ -34,3 +37,30 @@ uint32_t cli_bcapi_test1(struct cli_bc_ctx *ctx, uint32_t a, uint32_t b)
 {
     return (a==0xf00dbeef && b==0xbeeff00d) ? 0x12345678 : 0x55;
 }
+
+int32_t cli_bcapi_read(struct cli_bc_ctx* ctx, uint8_t *data, int32_t size)
+{
+    if (ctx->fd == -1)
+	return -1;
+    return pread(ctx->fd, data, size, ctx->off);
+}
+
+int32_t cli_bcapi_seek(struct cli_bc_ctx* ctx, int32_t pos, uint32_t whence)
+{
+    off_t off;
+    switch (whence) {
+	case 0:
+	    off = pos;
+	    break;
+	case 1:
+	    off = ctx->off + pos;
+	    break;
+	case 2:
+	    off = ctx->file_size + pos;
+	    break;
+    }
+    if (off < 0 || off > ctx->file_size)
+	return -1;
+    ctx->off = off;
+    return off;
+}

libclamav/bytecode_api.h

@@ -30,5 +30,22 @@ struct foo {
     struct foo *nxt;
 };
 
+#ifdef __CLAMBC__
+
 uint32_t test0(struct foo*, uint32_t);
 uint32_t test1(uint32_t, uint32_t);
+
+/* reads @size bytes from current file (if any) to @data, returns amount read */
+int32_t read(uint8_t *data, int32_t size);
+
+enum {
+    SEEK_SET=0,
+    SEEK_CUR,
+    SEEK_END
+};
+
+/* seeks current position to @pos, from @whence, returns current position from
+ * start of file */
+int32_t seek(int32_t pos, uint32_t whence);
+
+#endif

libclamav/bytecode_api_decl.c

@@ -26,30 +26,38 @@
 
 uint32_t cli_bcapi_test0(struct cli_bc_ctx *ctx, struct foo*, uint32_t);
 uint32_t cli_bcapi_test1(struct cli_bc_ctx *ctx, uint32_t, uint32_t);
+int32_t cli_bcapi_read(struct cli_bc_ctx *ctx, uint8_t*, int32_t);
+int32_t cli_bcapi_seek(struct cli_bc_ctx *ctx, int32_t, uint32_t);
 
 static uint16_t cli_tmp0[]={32, 70, 32};
 static uint16_t cli_tmp1[]={71};
 static uint16_t cli_tmp2[]={70};
 static uint16_t cli_tmp3[]={32, 32, 32};
+static uint16_t cli_tmp4[]={32, 65, 32};
 
 const struct cli_bc_type cli_apicall_types[]={
 	{DFunctionType, cli_tmp0, 3},
 	{DPointerType, cli_tmp1, 1},
 	{DStructType, cli_tmp2, 1},
-	{DFunctionType, cli_tmp3, 3}
+	{DFunctionType, cli_tmp3, 3},
+	{DFunctionType, cli_tmp4, 3}
 };
 
 const unsigned cli_apicall_maxtypes=sizeof(cli_apicall_types)/sizeof(cli_apicall_types[0]);
 const struct cli_apicall cli_apicalls[]={
 /* Bytecode APIcalls BEGIN */
 	{"test0", 0, 0, 1},
-	{"test1", 3, 0, 0}
+	{"test1", 3, 0, 0},
+	{"read", 4, 1, 1},
+	{"seek", 3, 1, 0}
 /* Bytecode APIcalls END */
 };
 const cli_apicall_int2 cli_apicalls0[] = {
-	cli_bcapi_test1
+	cli_bcapi_test1,
+	cli_bcapi_seek
 };
 const cli_apicall_pointer cli_apicalls1[] = {
-	(cli_apicall_pointer)cli_bcapi_test0
+	(cli_apicall_pointer)cli_bcapi_test0,
+	cli_bcapi_read
 };
 const unsigned cli_apicall_maxapi = sizeof(cli_apicalls)/sizeof(cli_apicalls[0]);

libclamav/bytecode_priv.h

@@ -95,6 +95,9 @@ struct cli_bc_ctx {
     operand_t *operands;
     uint16_t funcid;
     unsigned numParams;
+    size_t file_size;
+    off_t off;
+    int fd;
 };
 struct cli_all_bc;
 int cli_vm_execute(const struct cli_bc *bc, struct cli_bc_ctx *ctx, const struct cli_bc_func *func, const struct cli_bc_inst *inst);

libclamav/c++/bytecode2llvm.cpp

@@ -755,6 +755,8 @@ int cli_bytecode_prepare_jit(struct cli_all_bc *bcs)
 
 	for (unsigned i=0;i<bcs->count;i++) {
 	    const struct cli_bc *bc = &bcs->all_bcs[i];
+	    if (bc->state == bc_skip)
+		continue;
 	    LLVMCodegen Codegen(bc, M, bcs->engine->compiledFunctions, EE, 
 				OurFPM, apiFuncs);
 	    if (!Codegen.generate()) {