Fix #16210 - Show error message and update help for we ##io (#16427)

* Fix wen command for io.va=true, add two tests

libr/core/cio.c

@@ -421,19 +421,24 @@ R_API bool r_core_write_at(RCore *core, ut64 addr, const ut8 *buf, int size) {
 	return ret;
 }
 
-R_API int r_core_extend_at(RCore *core, ut64 addr, int size) {
-	int ret;
+R_API bool r_core_extend_at(RCore *core, ut64 addr, int size) {
 	if (!core->io || !core->file || size < 1) {
 		return false;
 	}
-	ret = r_io_use_fd (core->io, core->file->fd);
-	if (ret != -1) {
-		ret = r_io_extend_at (core->io, addr, size);
-		if (addr >= core->offset && addr <= core->offset+core->blocksize) {
-			r_core_block_read (core);
+	int io_va = r_config_get_i (core->config, "io.va");
+	if (io_va) {
+		RIOMap *map = r_io_map_get (core->io, core->offset);
+		if (map) {
+			addr = addr - map->itv.addr + map->delta;
 		}
+		r_config_set_i (core->config, "io.va", false);
 	}
-	return ret != -1;
+	int ret = r_io_extend_at (core->io, addr, size);
+	if (addr >= core->offset && addr <= core->offset+core->blocksize) {
+		r_core_block_read (core);
+	}
+	r_config_set_i (core->config, "io.va", io_va);
+	return ret;
 }
 
 R_API int r_core_shift_block(RCore *core, ut64 addr, ut64 b_size, st64 dist) {

libr/core/cmd_write.c

@@ -1,4 +1,4 @@
-/* radare - LGPL - Copyright 2009-2019 - pancake */
+/* radare - LGPL - Copyright 2009-2020 - pancake */
 
 #include "r_crypto.h"
 #include "r_config.h"
@@ -80,12 +80,12 @@ static const char *help_msg_wc[] = {
 };
 
 static const char *help_msg_we[] = {
-	"Usage", "", "write extend",
-	"wen", " <num>", "insert num null bytes at current offset",
-	"weN", " <addr> <len>", "insert bytes at address",
+	"Usage", "", "write extend # resize the file",
+	"wen", " <num>", "extend the underlying file inserting NUM null bytes at current offset",
+	"weN", " <addr> <len>", "extend current file and insert bytes at address",
 	"wes", " <addr>  <dist> <block_size>", "shift a blocksize left or write in the editor",
-	"wex", " <hex_bytes>", "insert bytes at current offset",
-	"weX", " <addr> <hex_bytes>", "insert bytes at address",
+	"wex", " <hex_bytes>", "insert bytes at current offset by extending the file",
+	"weX", " <addr> <hex_bytes>", "insert bytes at address by extending the file",
 	NULL
 };
 
@@ -944,13 +944,21 @@ static int cmd_write(void *data, const char *input) {
 		switch (input[1]) {
 		case 'n': // "wen"
 			if (input[2] == ' ') {
-				len = *input ? r_num_math (core->num, input+3) : 0;
+				len = *input ? r_num_math (core->num, input + 3) : 0;
 				if (len > 0) {
 					const ut64 cur_off = core->offset;
 					cmd_suc = r_core_extend_at (core, core->offset, len);
-					core->offset = cur_off;
-					r_core_block_read (core);
+					if (cmd_suc) {
+						core->offset = cur_off;
+						r_core_block_read (core);
+					} else {
+						eprintf ("r_io_extend failed\n");
+						cmd_suc = true;
+					}
 				}
+			} else {
+				eprintf ("Usage: wen [len]\n");
+				cmd_suc = true;
 			}
 			break;
 		case 'N': // "weN"
@@ -964,9 +972,13 @@ static int cmd_write(void *data, const char *input) {
 				if (len > 0){
 					ut64 cur_off = core->offset;
 					cmd_suc = r_core_extend_at (core, addr, len);
-					r_core_seek (core, cur_off, 1);
-					core->offset = addr;
-					r_core_block_read (core);
+					if (cmd_suc) {
+						r_core_seek (core, cur_off, 1);
+						core->offset = addr;
+						r_core_block_read (core);
+					} else {
+						eprintf ("r_io_extend failed\n");
+					}
 				}
 				cmd_suc = true;
 			}
@@ -1035,6 +1047,8 @@ static int cmd_write(void *data, const char *input) {
 						if (!r_core_write_at (core, addr, bytes, len)) {
 							cmd_write_fail (core);
 						}
+					} else {
+						eprintf ("r_io_extend failed\n");
 					}
 					core->offset = addr;
 					r_core_block_read (core);

libr/include/r_core.h

@@ -507,7 +507,7 @@ R_API int r_core_file_list(RCore *core, int mode);
 R_API int r_core_file_binlist(RCore *core);
 R_API bool r_core_file_bin_raise(RCore *core, ut32 num);
 R_API int r_core_seek_delta(RCore *core, st64 addr);
-R_API int r_core_extend_at(RCore *core, ut64 addr, int size);
+R_API bool r_core_extend_at(RCore *core, ut64 addr, int size);
 R_API bool r_core_write_at(RCore *core, ut64 addr, const ut8 *buf, int size);
 R_API int r_core_write_op(RCore *core, const char *arg, char op);
 R_API ut8* r_core_transform_op(RCore *core, const char *arg, char op);

test/new/db/cmd/write

@@ -1,3 +1,53 @@
+NAME=wen 3
+FILE=malloc://100
+CMDS=<<EOF
+r
+wen 3
+r
+EOF
+EXPECT=<<EOF
+100
+103
+EOF
+RUN
+
+NAME=wen 3 writable bin
+FILE=--
+CMDS=<<EOF
+mkdir .tmp
+cp ../bins/mach0/mac-ls2 .tmp/ls-wen
+o .tmp/ls-wen
+r
+wen 3
+r
+oo+
+r
+wen 3
+r
+rm .tmp/ls-wen
+EOF
+EXPECT=<<EOF
+38704
+38704
+38704
+38707
+EOF
+RUN
+
+NAME=wen 3 in readonly bin
+FILE=../bins/mach0/mac-ls2
+CMDS=<<EOF
+# cannot resize in va and non-write mode
+r
+wen 3
+r
+EOF
+EXPECT=<<EOF
+38704
+38704
+EOF
+RUN
+
 NAME=quoted comments bug
 FILE=malloc://1024
 CMDS=<<EOF