Update comments to to_xfer_partial implementations.

Some comments to to_xfer_partial implementations are out of date.
This patch updates them using the "Implement the to_xfer_partial
target_ops method" pattern.

gdb:

2014-02-11  Yao Qi  <yao@codesourcery.com>

	* aix-thread.c (aix_thread_xfer_partial): Update comments.
	* auxv.c (procfs_xfer_auxv, memory_xfer_auxv): Likewise.
	* bsd-uthread.c (bsd_uthread_xfer_partial): Likewise.
	* gnu-nat.c (gnu_xfer_memory): Likewise.
	* inf-ptrace.c (inf_ptrace_xfer_partial):  Likewise.
	* rs6000-nat.c (rs6000_xfer_partial): Likewise.
	* sparc-nat.c (sparc_xfer_wcookie): Likewise.
	* spu-linux-nat.c (spu_proc_xfer_spu): Likewise.

9 files changed, 29 insertions, 19 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 75eee7d..2fcd4a9 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,16 @@
 2014-02-11  Yao Qi  <yao@codesourcery.com>
 
+	* aix-thread.c (aix_thread_xfer_partial): Update comments.
+	* auxv.c (procfs_xfer_auxv, memory_xfer_auxv): Likewise.
+	* bsd-uthread.c (bsd_uthread_xfer_partial): Likewise.
+	* gnu-nat.c (gnu_xfer_memory): Likewise.
+	* inf-ptrace.c (inf_ptrace_xfer_partial):  Likewise.
+	* rs6000-nat.c (rs6000_xfer_partial): Likewise.
+	* sparc-nat.c (sparc_xfer_wcookie): Likewise.
+	* spu-linux-nat.c (spu_proc_xfer_spu): Likewise.
+
+2014-02-11  Yao Qi  <yao@codesourcery.com>
+
 	* target.h (enum target_xfer_error): Rename to ...
 	(enum target_xfer_status): ... it.  New.  All users updated.
 	(enum target_xfer_status) <TARGET_XFER_OK>, <TARGET_XFER_EOF>:
diff --git a/gdb/aix-thread.c b/gdb/aix-thread.c
index 4feb0cb..bd2a3a1 100644
--- a/gdb/aix-thread.c
+++ b/gdb/aix-thread.c
@@ -1678,9 +1678,7 @@ aix_thread_store_registers (struct target_ops *ops,
     }
 }
 
-/* Attempt a transfer all LEN bytes starting at OFFSET between the
-   inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer.
-   Return the number of bytes actually transferred.  */
+/* Implement the to_xfer_partial target_ops method.  */
 
 static enum target_xfer_status
 aix_thread_xfer_partial (struct target_ops *ops, enum target_object object,
diff --git a/gdb/auxv.c b/gdb/auxv.c
index 012f27b..2f4acf3 100644
--- a/gdb/auxv.c
+++ b/gdb/auxv.c
@@ -35,8 +35,9 @@
 #include <fcntl.h>
 
 
-/* This function handles access via /proc/PID/auxv, which is a common
-   method for native targets.  */
+/* Implement the to_xfer_partial target_ops method.  This function
+   handles access via /proc/PID/auxv, which is a common method for
+   native targets.  */
 
 static enum target_xfer_status
 procfs_xfer_auxv (gdb_byte *readbuf,
@@ -215,8 +216,8 @@ ld_so_xfer_auxv (gdb_byte *readbuf,
   return TARGET_XFER_OK;
 }
 
-/* This function is called like a to_xfer_partial hook, but must be
-   called with TARGET_OBJECT_AUXV.  It handles access to AUXV.  */
+/* Implement the to_xfer_partial target_ops method for
+   TARGET_OBJECT_AUXV.  It handles access to AUXV.  */
 
 enum target_xfer_status
 memory_xfer_auxv (struct target_ops *ops,
diff --git a/gdb/bsd-uthread.c b/gdb/bsd-uthread.c
index 446bbd2..bf6c390 100644
--- a/gdb/bsd-uthread.c
+++ b/gdb/bsd-uthread.c
@@ -331,8 +331,9 @@ bsd_uthread_store_registers (struct target_ops *ops,
     }
 }
 
-/* FIXME: This function is only there because otherwise GDB tries to
-   invoke deprecate_xfer_memory.  */
+/* Implement the to_xfer_partial target_ops method.  FIXME: This
+   function is only there because otherwise GDB tries to invoke
+   deprecate_xfer_memory.  */
 
 static enum target_xfer_status
 bsd_uthread_xfer_partial (struct target_ops *ops, enum target_object object,
diff --git a/gdb/gnu-nat.c b/gdb/gnu-nat.c
index b5a8da0..efafc35 100644
--- a/gdb/gnu-nat.c
+++ b/gdb/gnu-nat.c
@@ -2473,7 +2473,8 @@ out:
 
 
 
-/* Helper for gnu_xfer_partial that handles memory transfers.  */
+/* Implement the to_xfer_partial target_ops method for
+   TARGET_OBJECT_MEMORY.  */
 
 static enum target_xfer_status
 gnu_xfer_memory (gdb_byte *readbuf, const gdb_byte *writebuf,
diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index edcad5a..1ab6b0b 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -455,9 +455,7 @@ inf_ptrace_wait (struct target_ops *ops,
   return pid_to_ptid (pid);
 }
 
-/* Attempt a transfer all LEN bytes starting at OFFSET between the
-   inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer.
-   Return the number of bytes actually transferred.  */
+/* Implement the to_xfer_partial target_ops method.  */
 
 static enum target_xfer_status
 inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object,
diff --git a/gdb/rs6000-nat.c b/gdb/rs6000-nat.c
index 81a0874..4ba955c 100644
--- a/gdb/rs6000-nat.c
+++ b/gdb/rs6000-nat.c
@@ -374,10 +374,7 @@ rs6000_store_inferior_registers (struct target_ops *ops,
     }
 }
 
-
-/* Attempt a transfer all LEN bytes starting at OFFSET between the
-   inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer.
-   Return the number of bytes actually transferred.  */
+/* Implement the to_xfer_partial target_ops method.  */
 
 static enum target_xfer_status
 rs6000_xfer_partial (struct target_ops *ops, enum target_object object,
diff --git a/gdb/sparc-nat.c b/gdb/sparc-nat.c
index 169ba25..30b5124 100644
--- a/gdb/sparc-nat.c
+++ b/gdb/sparc-nat.c
@@ -256,7 +256,8 @@ sparc_store_inferior_registers (struct target_ops *ops,
 }
 
 
-/* Fetch StackGhost Per-Process XOR cookie.  */
+/* Implement the to_xfer_partial target_ops method for
+   TARGET_OBJECT_WCOOKIE.  Fetch StackGhost Per-Process XOR cookie.  */
 
 static enum target_xfer_status
 sparc_xfer_wcookie (struct target_ops *ops, enum target_object object,
diff --git a/gdb/spu-linux-nat.c b/gdb/spu-linux-nat.c
index a3fd369..a68e4e0 100644
--- a/gdb/spu-linux-nat.c
+++ b/gdb/spu-linux-nat.c
@@ -226,8 +226,10 @@ parse_spufs_run (int *fd, ULONGEST *addr)
 }
 
 
-/* Copy LEN bytes at OFFSET in spufs file ANNEX into/from READBUF or WRITEBUF,
+/* Implement the to_xfer_partial target_ops method for TARGET_OBJECT_SPU.
+   Copy LEN bytes at OFFSET in spufs file ANNEX into/from READBUF or WRITEBUF,
    using the /proc file system.  */
+
 static enum target_xfer_status
 spu_proc_xfer_spu (const char *annex, gdb_byte *readbuf,
 		   const gdb_byte *writebuf,