Make target_read_alloc & al return vectors

This patch started by changing target_read_alloc_1 to return a
byte_vector, to avoid manual memory management (in target_read_alloc_1
and in the callers).  To communicate failures to the callers, it
actually returns a gdb::optional<gdb::byte_vector>.

Adjusting target_read_stralloc was a bit more tricky, since it wants to
return a buffer of char, and not gdb_byte.  Since you can't just cast a
gdb::byte_vector into a gdb::def_vector<char>, I made
target_read_alloc_1 templated, so both versions (that return vectors of
gdb_byte and char) are generated.  Since target_read_stralloc now
returns a gdb::char_vector instead of a gdb::unique_xmalloc_ptr<char>, a
few callers need to be adjusted.

gdb/ChangeLog:

	* common/byte-vector.h (char_vector): New type.
	* target.h (target_read_alloc): Return
	gdb::optional<byte_vector>.
	(target_read_stralloc): Return gdb::optional<char_vector>.
	(target_get_osdata): Return gdb::optional<char_vector>.
	* target.c (target_read_alloc_1): Templatize.  Replacement
	manual memory management with vector.
	(target_read_alloc): Change return type, adjust.
	(target_read_stralloc): Change return type, adjust.
	(target_get_osdata): Change return type, adjust.
	* auxv.c (struct auxv_info) <length>: Remove.
	<data>: Change type to gdb::optional<byte_vector>.
	(auxv_inferior_data_cleanup): Free auxv_info with delete.
	(get_auxv_inferior_data): Allocate auxv_info with new, adjust.
	(target_auxv_search): Adjust.
	(fprint_target_auxv): Adjust.
	* avr-tdep.c (avr_io_reg_read_command): Adjust.
	* linux-tdep.c (linux_spu_make_corefile_notes): Adjust.
	(linux_make_corefile_notes): Adjust.
	* osdata.c (get_osdata): Adjust.
	* remote.c (remote_get_threads_with_qxfer): Adjust.
	(remote_memory_map): Adjust.
	(remote_traceframe_info): Adjust.
	(btrace_read_config): Adjust.
	(remote_read_btrace): Adjust.
	(remote_pid_to_exec_file): Adjust.
	* solib-aix.c (solib_aix_get_library_list): Adjust.
	* solib-dsbt.c (decode_loadmap): Don't free buf.
	(dsbt_get_initial_loadmaps): Adjust.
	* solib-svr4.c (svr4_current_sos_via_xfer_libraries): Adjust.
	* solib-target.c (solib_target_current_sos): Adjust.
	* tracepoint.c (sdata_make_value): Adjust.
	* xml-support.c (xinclude_start_include): Adjust.
	(xml_fetch_content_from_file): Adjust.
	* xml-support.h (xml_fetch_another): Change return type.
	(xml_fetch_content_from_file): Change return type.
	* xml-syscall.c (xml_init_syscalls_info): Adjust.
	* xml-tdesc.c (file_read_description_xml): Adjust.
	(fetch_available_features_from_target): Change return type.
	(target_fetch_description_xml): Adjust.
	(target_read_description_xml): Adjust.

1 files changed, 9 insertions, 10 deletions

diff --git a/gdb/solib-dsbt.c b/gdb/solib-dsbt.c
index b3b66ba..7a9b754 100644
--- a/gdb/solib-dsbt.c
+++ b/gdb/solib-dsbt.c
@@ -224,10 +224,10 @@ dsbt_print_loadmap (struct int_elf32_dsbt_loadmap *map)
 /* Decode int_elf32_dsbt_loadmap from BUF.  */
 
 static struct int_elf32_dsbt_loadmap *
-decode_loadmap (gdb_byte *buf)
+decode_loadmap (const gdb_byte *buf)
 {
   enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
-  struct ext_elf32_dsbt_loadmap *ext_ldmbuf;
+  const struct ext_elf32_dsbt_loadmap *ext_ldmbuf;
   struct int_elf32_dsbt_loadmap *int_ldmbuf;
 
   int version, seg, nsegs;
@@ -278,7 +278,6 @@ decode_loadmap (gdb_byte *buf)
 				    byte_order);
     }
 
-  xfree (ext_ldmbuf);
   return int_ldmbuf;
 }
 
@@ -292,26 +291,26 @@ static struct dsbt_info *get_dsbt_info (void);
 static void
 dsbt_get_initial_loadmaps (void)
 {
-  gdb_byte *buf;
   struct dsbt_info *info = get_dsbt_info ();
+  gdb::optional<gdb::byte_vector> buf
+    = target_read_alloc (&current_target, TARGET_OBJECT_FDPIC, "exec");
 
-  if (0 >= target_read_alloc (&current_target, TARGET_OBJECT_FDPIC,
-			      "exec", &buf))
+  if (!buf || buf->empty ())
     {
       info->exec_loadmap = NULL;
       error (_("Error reading DSBT exec loadmap"));
     }
-  info->exec_loadmap = decode_loadmap (buf);
+  info->exec_loadmap = decode_loadmap (buf->data ());
   if (solib_dsbt_debug)
     dsbt_print_loadmap (info->exec_loadmap);
 
-  if (0 >= target_read_alloc (&current_target, TARGET_OBJECT_FDPIC,
-			      "interp", &buf))
+  buf = target_read_alloc (&current_target, TARGET_OBJECT_FDPIC, "exec");
+  if (!buf || buf->empty ())
     {
       info->interp_loadmap = NULL;
       error (_("Error reading DSBT interp loadmap"));
     }
-  info->interp_loadmap = decode_loadmap (buf);
+  info->interp_loadmap = decode_loadmap (buf->data ());
   if (solib_dsbt_debug)
     dsbt_print_loadmap (info->interp_loadmap);
 }