[RFA 10/13] Remove cleanups from linux-tdep.c

[Tom Tromey <tom@tromey.com>]

This removes some cleanups from linux-tdep.c, replacing them with
def_vector or unique_xmalloc_ptr as appropriate.

gdb/ChangeLog
2017-11-02  Tom Tromey  <tom@tromey.com>

	* linux-tdep.c (linux_core_info_proc_mappings): Use
	gdb::def_vector.
	(linux_get_siginfo_data): Return gdb::unique_xmalloc_ptr.
	(linux_corefile_thread): Update.
---
 gdb/ChangeLog    |  7 +++++++
 gdb/linux-tdep.c | 45 ++++++++++++++-------------------------------
 2 files changed, 21 insertions(+), 31 deletions(-)

diff --git a/gdb/linux-tdep.c b/gdb/linux-tdep.c
index 83ff59faee..0350ccea16 100644
--- a/gdb/linux-tdep.c
+++ b/gdb/linux-tdep.c
@@ -998,10 +998,9 @@ linux_core_info_proc_mappings (struct gdbarch *gdbarch, const char *args)
 {
   asection *section;
   ULONGEST count, page_size;
-  unsigned char *descdata, *filenames, *descend, *contents;
+  unsigned char *descdata, *filenames, *descend;
   size_t note_size;
   unsigned int addr_size_bits, addr_size;
-  struct cleanup *cleanup;
   struct gdbarch *core_gdbarch = gdbarch_from_bfd (core_bfd);
   /* We assume this for reading 64-bit core files.  */
   gdb_static_assert (sizeof (ULONGEST) >= 8);
@@ -1020,12 +1019,12 @@ linux_core_info_proc_mappings (struct gdbarch *gdbarch, const char *args)
   if (note_size < 2 * addr_size)
     error (_("malformed core note - too short for header"));
 
-  contents = (unsigned char *) xmalloc (note_size);
-  cleanup = make_cleanup (xfree, contents);
-  if (!bfd_get_section_contents (core_bfd, section, contents, 0, note_size))
+  gdb::def_vector<unsigned char> contents (note_size);
+  if (!bfd_get_section_contents (core_bfd, section, contents.data (),
+				 0, note_size))
     error (_("could not get core note contents"));
 
-  descdata = contents;
+  descdata = contents.data ();
   descend = descdata + note_size;
 
   if (descdata[note_size - 1] != '\0')
@@ -1090,8 +1089,6 @@ linux_core_info_proc_mappings (struct gdbarch *gdbarch, const char *args)
 
       filenames += 1 + strlen ((char *) filenames);
     }
-
-  do_cleanups (cleanup);
 }
 
 /* Implement "info proc" for a corefile.  */
@@ -1516,7 +1513,6 @@ static char *
 linux_make_mappings_corefile_notes (struct gdbarch *gdbarch, bfd *obfd,
 				    char *note_data, int *note_size)
 {
-  struct cleanup *cleanup;
   struct linux_make_mappings_data mapping_data;
   struct type *long_type
     = arch_integer_type (gdbarch, gdbarch_long_bit (gdbarch), 0, "long");
@@ -1646,14 +1642,12 @@ linux_collect_thread_registers (const struct regcache *regcache,
    with the size of the data.  The caller is responsible for freeing
    the data.  */
 
-static gdb_byte *
+static gdb::unique_xmalloc_ptr<gdb_byte>
 linux_get_siginfo_data (thread_info *thread, struct gdbarch *gdbarch,
 			LONGEST *size)
 {
   struct type *siginfo_type;
-  gdb_byte *buf;
   LONGEST bytes_read;
-  struct cleanup *cleanups;
 
   if (!gdbarch_get_siginfo_type_p (gdbarch))
     return NULL;
@@ -1663,21 +1657,15 @@ linux_get_siginfo_data (thread_info *thread, struct gdbarch *gdbarch,
 
   siginfo_type = gdbarch_get_siginfo_type (gdbarch);
 
-  buf = (gdb_byte *) xmalloc (TYPE_LENGTH (siginfo_type));
-  cleanups = make_cleanup (xfree, buf);
+  gdb::unique_xmalloc_ptr<gdb_byte> buf
+    ((gdb_byte *) xmalloc (TYPE_LENGTH (siginfo_type)));
 
   bytes_read = target_read (&current_target, TARGET_OBJECT_SIGNAL_INFO, NULL,
-			    buf, 0, TYPE_LENGTH (siginfo_type));
+			    buf.get (), 0, TYPE_LENGTH (siginfo_type));
   if (bytes_read == TYPE_LENGTH (siginfo_type))
-    {
-      discard_cleanups (cleanups);
-      *size = bytes_read;
-    }
+    *size = bytes_read;
   else
-    {
-      do_cleanups (cleanups);
-      buf = NULL;
-    }
+    return NULL;
 
   return buf;
 }
@@ -1698,17 +1686,14 @@ static void
 linux_corefile_thread (struct thread_info *info,
 		       struct linux_corefile_thread_data *args)
 {
-  struct cleanup *old_chain;
   struct regcache *regcache;
-  gdb_byte *siginfo_data;
   LONGEST siginfo_size = 0;
 
   regcache = get_thread_arch_regcache (info->ptid, args->gdbarch);
 
   target_fetch_registers (regcache, -1);
-  siginfo_data = linux_get_siginfo_data (info, args->gdbarch, &siginfo_size);
-
-  old_chain = make_cleanup (xfree, siginfo_data);
+  gdb::unique_xmalloc_ptr<gdb_byte> siginfo_data
+    = linux_get_siginfo_data (info, args->gdbarch, &siginfo_size);
 
   args->note_data = linux_collect_thread_registers
     (regcache, info->ptid, args->obfd, args->note_data,
@@ -1722,9 +1707,7 @@ linux_corefile_thread (struct thread_info *info,
 					    args->note_data,
 					    args->note_size,
 					    "CORE", NT_SIGINFO,
-					    siginfo_data, siginfo_size);
-
-  do_cleanups (old_chain);
+					    siginfo_data.get (), siginfo_size);
 }
 
 /* Fill the PRPSINFO structure with information about the process being
-- 
2.13.6