Bug#22807 mysql_upgrade fails when called with a basedir-path containing spaces

- Create space safe strings for system() calls in mysql_upgrade.exe


client/mysql_upgrade.c:
  Bug#22807 mysql_upgrade fails when called with a basedir-path containing spaces
  - Make use of new dynstr_append_os_quoted function to produce a string safe for
  passing to the system() function.                                              
  - Refactor possible source of assertion.
include/my_sys.h:
  Bug#22807 mysql_upgrade fails when called with a basedir-path containing spaces
  - Declare dynstr_append_os_quoted function.
mysys/string.c:
  Bug#22807 mysql_upgrade fails when called with a basedir-path containing spaces
  - Define dynstr_append_os_quoted function.  This function will concatenate any 
  number of strings, escapes any OS quote in the result then surround the whole  
  affair in another set of quotes which is finally appended to specified         
  DYNAMIC_STRING.

1 files changed, 2 insertions, 0 deletions

diff --git a/include/my_sys.h b/include/my_sys.h
index d19091a85e8..cbcc6cf7486 100644
--- a/include/my_sys.h
+++ b/include/my_sys.h
@@ -781,6 +781,8 @@ extern my_bool init_dynamic_string(DYNAMIC_STRING *str, const char *init_str,
 extern my_bool dynstr_append(DYNAMIC_STRING *str, const char *append);
 my_bool dynstr_append_mem(DYNAMIC_STRING *str, const char *append,
 			  uint length);
+extern my_bool dynstr_append_os_quoted(DYNAMIC_STRING *str, const char *append,
+                                       ...);
 extern my_bool dynstr_set(DYNAMIC_STRING *str, const char *init_str);
 extern my_bool dynstr_realloc(DYNAMIC_STRING *str, ulong additional_size);
 extern void dynstr_free(DYNAMIC_STRING *str);