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, 18 insertions, 26 deletions

diff --git a/gdb/auxv.c b/gdb/auxv.c
index 26cc63e0204..ce7a63b8943 100644
--- a/gdb/auxv.c
+++ b/gdb/auxv.c
@@ -304,8 +304,7 @@ static const struct inferior_data *auxv_inferior_data;
     overhead of transfering data from a remote target to the local host.  */
 struct auxv_info
 {
-  LONGEST length;
-  gdb_byte *data;
+  gdb::optional<gdb::byte_vector> data;
 };
 
 /* Handles the cleanup of the auxv cache for inferior INF.  ARG is ignored.
@@ -323,8 +322,7 @@ auxv_inferior_data_cleanup (struct inferior *inf, void *arg)
   info = (struct auxv_info *) inferior_data (inf, auxv_inferior_data);
   if (info != NULL)
     {
-      xfree (info->data);
-      xfree (info);
+      delete info;
       set_inferior_data (inf, auxv_inferior_data, NULL);
     }
 }
@@ -358,9 +356,8 @@ get_auxv_inferior_data (struct target_ops *ops)
   info = (struct auxv_info *) inferior_data (inf, auxv_inferior_data);
   if (info == NULL)
     {
-      info = XCNEW (struct auxv_info);
-      info->length = target_read_alloc (ops, TARGET_OBJECT_AUXV,
-					NULL, &info->data);
+      info = new auxv_info;
+      info->data = target_read_alloc (ops, TARGET_OBJECT_AUXV, NULL);
       set_inferior_data (inf, auxv_inferior_data, info);
     }
 
@@ -375,20 +372,17 @@ int
 target_auxv_search (struct target_ops *ops, CORE_ADDR match, CORE_ADDR *valp)
 {
   CORE_ADDR type, val;
-  gdb_byte *data;
-  gdb_byte *ptr;
-  struct auxv_info *info;
-
-  info = get_auxv_inferior_data (ops);
+  auxv_info *info = get_auxv_inferior_data (ops);
 
-  data = info->data;
-  ptr = data;
+  if (!info->data)
+    return -1;
 
-  if (info->length <= 0)
-    return info->length;
+  gdb_byte *data = info->data->data ();
+  gdb_byte *ptr = data;
+  size_t len = info->data->size ();
 
   while (1)
-    switch (target_auxv_parse (ops, &ptr, data + info->length, &type, &val))
+    switch (target_auxv_parse (ops, &ptr, data + len, &type, &val))
       {
       case 1:			/* Here's an entry, check it.  */
 	if (type == match)
@@ -528,19 +522,17 @@ fprint_target_auxv (struct ui_file *file, struct target_ops *ops)
 {
   struct gdbarch *gdbarch = target_gdbarch ();
   CORE_ADDR type, val;
-  gdb_byte *data;
-  gdb_byte *ptr;
-  struct auxv_info *info;
   int ents = 0;
+  auxv_info *info = get_auxv_inferior_data (ops);
 
-  info = get_auxv_inferior_data (ops);
+  if (!info->data)
+    return -1;
 
-  data = info->data;
-  ptr = data;
-  if (info->length <= 0)
-    return info->length;
+  gdb_byte *data = info->data->data ();
+  gdb_byte *ptr = data;
+  size_t len = info->data->size ();
 
-  while (target_auxv_parse (ops, &ptr, data + info->length, &type, &val) > 0)
+  while (target_auxv_parse (ops, &ptr, data + len, &type, &val) > 0)
     {
       gdbarch_print_auxv_entry (gdbarch, file, type, val);
       ++ents;