[STDCXX-161] filebuf::sgetn() fails after sputn() in stdio mode

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 4.1.3
• Fix Version/s: 4.1.4
• Component/s: 27. Input/Output

Environment

all

• Assignee: Martin Sebor
• Reporter: Martin Sebor
• Created: 04/Mar/06 09:39
• Updated: 22/Apr/08 02:25
• Resolved: 05/Mar/06 07:24

Description

The program below fails at runtime (std::ios::stdio is an extension of this implementation that forces the filebuf to use the stdio facilities for I/O instead of OS native calls).

$ cat t.cpp && gmake t && ./t
#include <fstream>
#include <cassert>

int main ()
{
std::filebuf fb;

assert (0 != fb.open ("testfile.text", std::ios::out));
assert (6 == fb.sputn ("ABCDEF", 6));
assert (0 != fb.close ());

assert (0 != fb.open ("testfile.text",
std::ios::in | std::ios::out | std::ios::stdio));

assert (3 == fb.sputn ("abc", 3));
assert (-1 != fb.pubsync ());

char buf [3] = "";
assert (3 == fb.sgetn (buf, sizeof buf));
assert (0 == std::filebuf::traits_type::compare ("DEF", buf, 3));
}
aCC -c -I/build/sebor/dev/stdlib/include/ansi -I/usr/include -D_RWSTDDEBUG -mt -D_RWSTD_USE_CONFIG -I/build/sebor/aCC-3.63-15s/include -I/build/sebor/dev/stdlib/include -I/build/sebor/dev/stdlib/../rwtest -I/build/sebor/dev/stdlib/../rwtest/include -I/build/sebor/dev/stdlib/tests/include -Aa +nostl -g +d +w +W392 +W655 +W684 +W818 +W819 +W849 t.cpp
aCC t.o -o t -L/build/sebor/aCC-3.63-15s/rwtest -lrwtest15s -Aa +nostl -Wl,+s -Wl,+vnocompatwarnings -L/build/sebor/aCC-3.63-15s/lib -mt -L/build/sebor/aCC-3.63-15s/lib -lstd15s -lm
Assertion failed: 0 == std::filebuf::traits_type::compare ("DEF", buf, 3), file t.cpp, line 20
ABORT instruction (core dumped)