Share code on to_xfer_partial for tfile and ctf target

In the to_xfer_partial implementations of ctf and tfile, the code on
reading from read-only sections is duplicated.  This patch moves it to
a separate function exec_read_partial_read_only.

gdb:

2014-02-23  Yao Qi  <yao@codesourcery.com>

	* ctf.c (ctf_xfer_partial): Move code to ...
	* exec.c (exec_read_partial_read_only): ... it.  New function.
	* tracefile-tfile.c (tfile_xfer_partial): Likewise.
	* tracefile.c: Include "exec.h".
	* exec.h (exec_read_partial_read_only): Declare.

1 files changed, 47 insertions, 0 deletions

diff --git a/gdb/exec.c b/gdb/exec.c
index 7f53a50776..74c61eb810 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -530,6 +530,53 @@ remove_target_sections (void *owner)
 
 
 
+enum target_xfer_status
+exec_read_partial_read_only (gdb_byte *readbuf, ULONGEST offset,
+			     ULONGEST len, ULONGEST *xfered_len)
+{
+  /* It's unduly pedantic to refuse to look at the executable for
+     read-only pieces; so do the equivalent of readonly regions aka
+     QTro packet.  */
+  if (exec_bfd != NULL)
+    {
+      asection *s;
+      bfd_size_type size;
+      bfd_vma vma;
+
+      for (s = exec_bfd->sections; s; s = s->next)
+	{
+	  if ((s->flags & SEC_LOAD) == 0
+	      || (s->flags & SEC_READONLY) == 0)
+	    continue;
+
+	  vma = s->vma;
+	  size = bfd_get_section_size (s);
+	  if (vma <= offset && offset < (vma + size))
+	    {
+	      ULONGEST amt;
+
+	      amt = (vma + size) - offset;
+	      if (amt > len)
+		amt = len;
+
+	      amt = bfd_get_section_contents (exec_bfd, s,
+					      readbuf, offset - vma, amt);
+
+	      if (amt == 0)
+		return TARGET_XFER_EOF;
+	      else
+		{
+		  *xfered_len = amt;
+		  return TARGET_XFER_OK;
+		}
+	    }
+	}
+    }
+
+  /* Indicate failure to find the requested memory block.  */
+  return TARGET_XFER_E_IO;
+}
+
 VEC(mem_range_s) *
 section_table_available_memory (VEC(mem_range_s) *memory,
 				CORE_ADDR memaddr, ULONGEST len,