gdb: make extract_integer take an array_view

I think it would make sense for extract_integer, extract_signed_integer
and extract_unsigned_integer to take an array_view.  This way, when we
extract an integer, we can validate that we don't overflow the buffer
passed by the caller (e.g. ask to extract a 4-byte integer but pass a
2-byte buffer).

 - Change extract_integer to take an array_view
 - Add overloads of extract_signed_integer and extract_unsigned_integer
   that take array_views.  Keep the existing versions so we don't
   need to change all callers, but make them call the array_view
   versions.

This shortens some places like:

  result = extract_unsigned_integer (value_contents (result_val).data (),
				     TYPE_LENGTH (value_type (result_val)),
				     byte_order);

into

  result = extract_unsigned_integer (value_contents (result_val), byte_order);

value_contents returns an array view that is of length
`TYPE_LENGTH (value_type (result_val))` already, so the length is
implicitly communicated through the array view.

Change-Id: Ic1c1f98c88d5c17a8486393af316f982604d6c95

1 files changed, 1 insertions, 1 deletions

diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c
index 898b73f..7c62745 100644
--- a/gdb/i386-linux-tdep.c
+++ b/gdb/i386-linux-tdep.c
@@ -549,7 +549,7 @@ i386_linux_get_syscall_number_from_regcache (struct regcache *regcache)
      is stored at %eax register.  */
   regcache->cooked_read (I386_LINUX_ORIG_EAX_REGNUM, buf);
 
-  ret = extract_signed_integer (buf, 4, byte_order);
+  ret = extract_signed_integer (buf, byte_order);
 
   return ret;
 }