procfs.c: Don't install a deprecated_xfer_memory method

This removes yet another instance of a deprecated_xfer_memory user,
and fixes a nasty regression as a side-effect:

    (gdb) start
    Temporary breakpoint 1 at 0x19070: file simple_main.adb, line 4.
    Starting program: /[...]/simple_main
    Warning:
    Cannot insert breakpoint 1.
    Cannot access memory at address 0x19070
    Cannot insert breakpoint -3.
    Temporarily disabling shared library breakpoints:
    breakpoint #-3

The regression was introduced by the to_xfer_partial transition
to return a status enum.  procfs_xfer_partial was updated but
not the case where object is TARGET_OBJECT_MEMORY.  As result,
procfs_xfer_partial was returning the length xfered rather than
the status, and the xfered buffer was left uninitialized.

gdb/
2014-02-19  Pedro Alves  <palves@redhat.com>

	* procfs.c (procfs_target): Don't install procfs_xfer_memory as
	deprecated_xfer_memory hook.
	(procfs_xfer_partial): Call procfs_xfer_memory instead
	of the deprecated_xfer_memory target hook.
	(procfs_xfer_memory): Adjust interface as a to_xfer_partial
	helper.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index bc8573c..b642ac9 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,12 @@
+2014-02-24  Pedro Alves  <palves@redhat.com>
+
+       * procfs.c (procfs_target): Don't install procfs_xfer_memory as
+       deprecated_xfer_memory hook.
+       (procfs_xfer_partial): Call procfs_xfer_memory instead
+       of the deprecated_xfer_memory target hook.
+       (procfs_xfer_memory): Adjust interface as a to_xfer_partial
+       helper.
+
 2014-02-24  Yuanhui Zhang  <asmwarrior@gmail.com>
 
        * windows-nat.c (windows_xfer_shared_libraries): Return

diff --git a/gdb/procfs.c b/gdb/procfs.c
index 822e1e0..8204747 100644 (file)
--- a/gdb/procfs.c
+++ b/gdb/procfs.c
@@ -127,9 +127,10 @@ static void procfs_create_inferior (struct target_ops *, char *,
                                    char *, char **, int);
 static ptid_t procfs_wait (struct target_ops *,
                           ptid_t, struct target_waitstatus *, int);
-static int procfs_xfer_memory (CORE_ADDR, gdb_byte *, int, int,
-                              struct mem_attrib *attrib,
-                              struct target_ops *);
+static enum target_xfer_status procfs_xfer_memory (gdb_byte *,
+                                                  const gdb_byte *,
+                                                  ULONGEST, ULONGEST,
+                                                  ULONGEST *);
 static target_xfer_partial_ftype procfs_xfer_partial;
 
 static int procfs_thread_alive (struct target_ops *ops, ptid_t);
@@ -197,7 +198,6 @@ procfs_target (void)
   t->to_fetch_registers = procfs_fetch_registers;
   t->to_store_registers = procfs_store_registers;
   t->to_xfer_partial = procfs_xfer_partial;
-  t->deprecated_xfer_memory = procfs_xfer_memory;
   t->to_pass_signals = procfs_pass_signals;
   t->to_files_info = procfs_files_info;
   t->to_stop = procfs_stop;
@@ -3986,13 +3986,7 @@ procfs_xfer_partial (struct target_ops *ops, enum target_object object,
   switch (object)
     {
     case TARGET_OBJECT_MEMORY:
-      if (readbuf)
-       return (*ops->deprecated_xfer_memory) (offset, readbuf,
-                                              len, 0/*read*/, NULL, ops);
-      if (writebuf)
-       return (*ops->deprecated_xfer_memory) (offset, (gdb_byte *) writebuf,
-                                              len, 1/*write*/, NULL, ops);
-      return TARGET_XFER_E_IO;
+      return procfs_xfer_memory (readbuf, writebuf, offset, len, xfered_len);
 
 #ifdef NEW_PROC_API
     case TARGET_OBJECT_AUXV:
@@ -4009,23 +4003,15 @@ procfs_xfer_partial (struct target_ops *ops, enum target_object object,
     }
 }
 
+/* Helper for procfs_xfer_partial that handles memory transfers.
+   Arguments are like target_xfer_partial.  */
 
-/* Transfer LEN bytes between GDB address MYADDR and target address
-   MEMADDR.  If DOWRITE is non-zero, transfer them to the target,
-   otherwise transfer them from the target.  TARGET is unused.
-
-   The return value is 0 if an error occurred or no bytes were
-   transferred.  Otherwise, it will be a positive value which
-   indicates the number of bytes transferred between gdb and the
-   target.  (Note that the interface also makes provisions for
-   negative values, but this capability isn't implemented here.)  */
-
-static int
-procfs_xfer_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len, int dowrite,
-                   struct mem_attrib *attrib, struct target_ops *target)
+static enum target_xfer_status
+procfs_xfer_memory (gdb_byte *readbuf, const gdb_byte *writebuf,
+                   ULONGEST memaddr, ULONGEST len, ULONGEST *xfered_len)
 {
   procinfo *pi;
-  int nbytes = 0;
+  int nbytes;
 
   /* Find procinfo for main process.  */
   pi = find_procinfo_or_die (ptid_get_pid (inferior_ptid), 0);
@@ -4033,31 +4019,26 @@ procfs_xfer_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len, int dowrite,
       open_procinfo_files (pi, FD_AS) == 0)
     {
       proc_warn (pi, "xfer_memory, open_proc_files", __LINE__);
-      return 0;
+      return TARGET_XFER_E_IO;
     }
 
-  if (lseek (pi->as_fd, (off_t) memaddr, SEEK_SET) == (off_t) memaddr)
+  if (lseek (pi->as_fd, (off_t) memaddr, SEEK_SET) != (off_t) memaddr)
+    return TARGET_XFER_E_IO;
+
+  if (writebuf != NULL)
     {
-      if (dowrite)
-       {
-#ifdef NEW_PROC_API
-         PROCFS_NOTE ("write memory:\n");
-#else
-         PROCFS_NOTE ("write memory:\n");
-#endif
-         nbytes = write (pi->as_fd, myaddr, len);
-       }
-      else
-       {
-         PROCFS_NOTE ("read  memory:\n");
-         nbytes = read (pi->as_fd, myaddr, len);
-       }
-      if (nbytes < 0)
-       {
-         nbytes = 0;
-       }
+      PROCFS_NOTE ("write memory:\n");
+      nbytes = write (pi->as_fd, writebuf, len);
+    }
+  else
+    {
+      PROCFS_NOTE ("read  memory:\n");
+      nbytes = read (pi->as_fd, readbuf, len);
     }
-  return nbytes;
+  if (nbytes <= 0)
+    return TARGET_XFER_E_IO;
+  *xfered_len = nbytes;
+  return TARGET_XFER_OK;
 }
 
 /* Called by target_resume before making child runnable.  Mark cached