[gsoap] Crash in gsoap when populating a string array.

[Jon Earle]

Hey folks,

I have the following code (extracts):

header (for soapcpp2):

class stringArray
{ public:
     std::string   **__ptr;
     int             __size;

     stringArray();

     void add(std::string str, struct soap * soap);
     void add(std::string * str, struct soap * soap);

     void resize(struct soap * soap);
};

void stringArray::resize(struct soap * soap)
{
     std::string **newPtr = (std::string **)soap_new_std__string(soap,
__size + 5);

     // Copy any existing array to the new array and free the old array.
     if (__ptr)
     {
         newPtr = __ptr;
         soap_delete(soap, __ptr);
     }

     __ptr = newPtr;
}

void stringArray::add(string * str, struct soap * soap)
{
     // If this is the first time through, or we have exhausted the
current array limit, then
     // reallocate the array.
     if (__size == 0 || (__size % 5) == 0)
     {
         resize(soap);
     }

     *(__ptr)[__size] = *str;

     __size++;
}

void stringArray::add(string str, struct soap * soap)
{
     add(&str, soap);
}

when I run my program, I get the following crash:

(gdb) b stringArray.cpp:72
Breakpoint 1 at 0x80adc17: file /root/nm2/stringArray.cpp, line 72.
(gdb) run
...
Breakpoint 1, stringArray::add (this=0xb62e8304, str=0xb62e8244,
soap=0x8f48838) at /root/nm2/stringArray.cpp:72
72          *(__ptr)[__size] = *str;
(gdb) n

Program received signal SIGSEGV, Segmentation fault.
0x00ca29e9 in __gnu_cxx::__exchange_and_add () from
/usr/lib/libstdc++.so.6
(gdb) bt
#0  0x00ca29e9 in __gnu_cxx::__exchange_and_add () from
/usr/lib/libstdc++.so.6
#1  0x00c85883 in std::string::assign () from /usr/lib/libstdc++.so.6
#2  0x00c858f4 in std::string::operator= () from /usr/lib/libstdc++.so.6
#3  0x080adc3a in stringArray::add (this=0xb62e8304, str=0xb62e8244,
soap=0x8f48838)
     at /root/nm2/stringArray.cpp:72
#4  0x080adc6f in stringArray::add (this=0xb62e8304, [EMAIL PROTECTED],
soap=0x8f48838)
     at /root/nm2/stringArray.cpp:82
#5  0x080e8b55 in ns1__myservice (soap=0x8f48838, value=1) at
services.cpp:906
#6  0x080feb9d in soap_serve_ns1__myservice (soap=0x8f48838) at
soapServer.cpp:917
#7  0x081029af in soap_serve_request (soap=0x8f48838) at
soapServer.cpp:111
#8  0x0810353b in soap_serve (soap=0x8f48838) at soapServer.cpp:49
#9  0x080b97da in process_queue (soap=0x8f48838) at myserver.cpp:228
#10 0x009a245b in start_thread () from /lib/libpthread.so.0
#11 0x007c223e in clone () from /lib/libc.so.6

I'm at my wits end with this one.  I've done some google searches for
"__exchange_and_add SIGSEGV", but not much turned up... certainly no
resolutions.

Any ideas as to what I might be doing wrong or what could be the issue? 
Are there any workarounds or alternate approaches I can take?

gsoap is 2.7.10 - didn't see any mention of this being an issue in
recent times with gsoap so haven't yet pursued updating.

/usr/lib/libstdc++.so.6 is from libstdc++-4.1.2-13.fc6 -- old, yes, but
it's what we have to work with.

Cheers!
Jon