Fix memory leak in add_symbol_file_command

I happened to notice that add_symbol_file_command leaks "sect_opts".
This patch fixes the leak by changing sect_opts to be a std::vector.

I had to change the logic in the loop a little bit.  Previously, it
was incrementing section_index after completing an entry; but this
changes it to push a new entry when the name is seen.

I believe the argument parsing here is mildly incorrect, in that
nothing checks whether the -s option actually had any arguments.
Maybe gdb can crash if "-s NAME" is given without an argument.  I
didn't try to fix this in this patch, but I do have another patch I
can send later that fixes it up.

Regression tested on the buildbot.

ChangeLog
2017-08-11  Tom Tromey  <tom@tromey.com>

	* symfile.c (add_symbol_file_command): Use std::vector.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 384d4d305b632a531d5166fab9509fd94c2ac0a8..dcb591de17f2c9caba5b5a3490ff800f2f9c2f95 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2017-08-11  Tom Tromey  <tom@tromey.com>
+
+       * symfile.c (add_symbol_file_command): Use std::vector.
+
 2017-08-14  Tom Tromey  <tom@tromey.com>
 
        * break-catch-throw.c (handle_gnu_v3_exceptions): Use std::move.

diff --git a/gdb/symfile.c b/gdb/symfile.c
index 3e2df9bda43d3c126d39d305bd60739a16792ad3..d600b613729699160922d3dbaf3e1bc42edbb4a6 100644 (file)
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -2205,10 +2205,8 @@ add_symbol_file_command (char *args, int from_tty)
   struct gdbarch *gdbarch = get_current_arch ();
   gdb::unique_xmalloc_ptr<char> filename;
   char *arg;
-  int section_index = 0;
   int argcnt = 0;
   int sec_num = 0;
-  int i;
   int expecting_sec_name = 0;
   int expecting_sec_addr = 0;
   struct objfile *objf;
@@ -2225,13 +2223,9 @@ add_symbol_file_command (char *args, int from_tty)
   };
 
   struct section_addr_info *section_addrs;
-  struct sect_opt *sect_opts = NULL;
-  size_t num_sect_opts = 0;
+  std::vector<sect_opt> sect_opts;
   struct cleanup *my_cleanups = make_cleanup (null_cleanup, NULL);
 
-  num_sect_opts = 16;
-  sect_opts = XNEWVEC (struct sect_opt, num_sect_opts);
-
   dont_repeat ();
 
   if (args == NULL)
@@ -2251,16 +2245,8 @@ add_symbol_file_command (char *args, int from_tty)
        {
          /* The second argument is always the text address at which
             to load the program.  */
-         sect_opts[section_index].name = ".text";
-         sect_opts[section_index].value = arg;
-         if (++section_index >= num_sect_opts)
-           {
-             num_sect_opts *= 2;
-             sect_opts = ((struct sect_opt *)
-                          xrealloc (sect_opts,
-                                    num_sect_opts
-                                    * sizeof (struct sect_opt)));
-           }
+         sect_opt sect = { ".text", arg };
+         sect_opts.push_back (sect);
        }
       else
        {
@@ -2268,21 +2254,14 @@ add_symbol_file_command (char *args, int from_tty)
             to an option.  */
          if (expecting_sec_name)
            {
-             sect_opts[section_index].name = arg;
+             sect_opt sect = { arg, NULL };
+             sect_opts.push_back (sect);
              expecting_sec_name = 0;
            }
          else if (expecting_sec_addr)
            {
-             sect_opts[section_index].value = arg;
+             sect_opts.back ().value = arg;
              expecting_sec_addr = 0;
-             if (++section_index >= num_sect_opts)
-               {
-                 num_sect_opts *= 2;
-                 sect_opts = ((struct sect_opt *)
-                              xrealloc (sect_opts,
-                                        num_sect_opts
-                                        * sizeof (struct sect_opt)));
-               }
            }
          else if (strcmp (arg, "-readnow") == 0)
            flags |= OBJF_READNOW;
@@ -2301,7 +2280,7 @@ add_symbol_file_command (char *args, int from_tty)
      filename, and the second is the address where this file has been
      loaded.  Abort now if this address hasn't been provided by the
      user.  */
-  if (section_index < 1)
+  if (sect_opts.empty ())
     error (_("The address where %s has been loaded is missing"),
           filename.get ());
 
@@ -2313,13 +2292,13 @@ add_symbol_file_command (char *args, int from_tty)
 
   printf_unfiltered (_("add symbol table from file \"%s\" at\n"),
                     filename.get ());
-  section_addrs = alloc_section_addr_info (section_index);
+  section_addrs = alloc_section_addr_info (sect_opts.size ());
   make_cleanup (xfree, section_addrs);
-  for (i = 0; i < section_index; i++)
+  for (sect_opt &sect : sect_opts)
     {
       CORE_ADDR addr;
-      const char *val = sect_opts[i].value;
-      const char *sec = sect_opts[i].name;
+      const char *val = sect.value;
+      const char *sec = sect.name;
 
       addr = parse_and_eval_address (val);