Handle memory error in print_insn_rl78_common

Nowadays, memory error in rl78 disassembly is not handled, so if I
start a fresh GDB, and disassemble,

(gdb) set architecture rl78
The target architecture is assumed to be rl78
(gdb) disassemble 0x0,+4
Dump of assembler code from 0x0 to 0x4:
   0x00000000:	nop
   0x00000001:	nop
   0x00000002:	nop
   0x00000003:	nop

the output is wrong.  This patch adds code to call dis->memory_error_func
on memory error, and longjmp to print_insn_rl78_common.  With this
patch applied,

(gdb) set architecture rl78
The target architecture is assumed to be rl78
(gdb) disassemble 0,+4
Dump of assembler code from 0x0 to 0x4:
   0x00000000:	Cannot access memory at address 0x0

opcodes:

2016-12-12  Yao Qi  <yao.qi@linaro.org>

	* rl78-dis.c: Include <setjmp.h>.
	(struct private): New.
	(rl78_get_byte): Check return value of read_memory_func, and
	call memory_error_func and OPCODES_SIGLONGJMP on error.
	(print_insn_rl78_common): Call OPCODES_SIGJMP.

1 files changed, 28 insertions, 4 deletions

diff --git a/opcodes/rl78-dis.c b/opcodes/rl78-dis.c
index a23999d..c2b36db 100644
--- a/opcodes/rl78-dis.c
+++ b/opcodes/rl78-dis.c
@@ -29,6 +29,8 @@
 #include "opcode/rl78.h"
 #include "elf/rl78.h"
 
+#include <setjmp.h>
+
 #define DEBUG_SEMANTICS 0
 
 typedef struct
@@ -37,16 +39,30 @@ typedef struct
   disassemble_info * dis;
 } RL78_Data;
 
+struct private
+{
+  OPCODES_SIGJMP_BUF bailout;
+};
+
 static int
 rl78_get_byte (void * vdata)
 {
   bfd_byte buf[1];
   RL78_Data *rl78_data = (RL78_Data *) vdata;
+  int status;
+
+  status = rl78_data->dis->read_memory_func (rl78_data->pc,
+					     buf,
+					     1,
+					     rl78_data->dis);
+  if (status != 0)
+    {
+      struct private *priv = (struct private *) rl78_data->dis->private_data;
 
-  rl78_data->dis->read_memory_func (rl78_data->pc,
-				  buf,
-				  1,
-				  rl78_data->dis);
+      rl78_data->dis->memory_error_func (status, rl78_data->pc,
+					 rl78_data->dis);
+      OPCODES_SIGLONGJMP (priv->bailout, 1);
+    }
 
   rl78_data->pc ++;
   return buf[0];
@@ -92,10 +108,18 @@ print_insn_rl78_common (bfd_vma addr, disassemble_info * dis, RL78_Dis_Isa isa)
 #if DEBUG_SEMANTICS
   static char buf[200];
 #endif
+  struct private priv;
 
+  dis->private_data = (PTR) &priv;
   rl78_data.pc = addr;
   rl78_data.dis = dis;
 
+  if (OPCODES_SIGSETJMP (priv.bailout) != 0)
+    {
+      /* Error return.  */
+      return -1;
+    }
+
   rv = rl78_decode_opcode (addr, &opcode, rl78_get_byte, &rl78_data, isa);
 
   dis->bytes_per_line = 10;