// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build gc

#include "_cgo_export.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

/* Test calling panic from C.  This is what SWIG does.  */

extern void crosscall2(void (*fn)(void *, int), void *, int);
extern void _cgo_panic(void *, int);
extern void _cgo_allocate(void *, int);

void
callPanic(void)
{

In C, a function argument written as a fixed size array
actually requires a pointer to the first element of the array.
C compilers are aware of this calling convention and adjust
the call accordingly, but Go cannot. In Go, you must pass
the pointer to the first element explicitly: C.f(&C.x[0]).

Calling variadic C functions is not supported. It is possible to
circumvent this by using a C function wrapper. For example:

	package main

// license that can be found in the LICENSE file.

//go:build gccgo

#include "_cgo_export.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

/* Test calling panic from C.  This is what SWIG does.  */

extern void _cgo_panic(const char *);
extern void *_cgo_allocate(size_t);

void
callPanic(void)
{
	_cgo_panic("panic from C");

	ctxFile
	ctxDecl
	ctxSpec
	ctxDefer
	ctxCall  // any function call other than ctxCall2
	ctxCall2 // function call whose result is assigned to two variables
	ctxSelector
)

// walk walks the AST x, calling visit(f, x, context) for each node.
func (f *File) walk(x interface{}, context astContext, visit func(*File, interface{}, astContext)) {
	visit(f, x, context)
	switch n := x.(type) {
	case *ast.Expr:

	{"byte", iotest.OneByteReader},
	{"half", iotest.HalfReader},
	{"data+err", iotest.DataErrReader},
	{"timeout", iotest.TimeoutReader},
}

// Call ReadString (which ends up calling everything else)
// to accumulate the text of a file.
func readLines(b *Reader) string {
	s := ""
	for {
		s1, err := b.ReadString('\n')
		if err == io.EOF {
			break
		}

or, for function parameters and results, the signature
of a <a href="#Function_declarations">function declaration</a>
or <a href="#Function_literals">function literal</a> reserves
storage for a named variable.

Calling the built-in function <a href="#Allocation"><code>new</code></a>
or taking the address of a <a href="#Composite_literals">composite literal</a>
allocates storage for a variable at run time.

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include "_cgo_export.h"

/* Test calling a Go function with multiple return values.  */

void
callMulti(void)
{
	struct multi_return result = multi();
	assert(strcmp(result.r0, "multi") == 0);
	assert(result.r1 == 0);
	free(result.r0);

// that point, the program is terminated with a non-zero exit code. This
// termination sequence is called panicking and can be controlled by the
// built-in function recover.
//
// Starting in Go 1.21, calling panic with a nil interface value or an
// untyped nil causes a run-time error (a different panic).
// The GODEBUG setting panicnil=1 disables the run-time error.
func panic(v any)

	}
}

func TestCVE202139293(t *testing.T) {
	// directory size is so large, that the check in Reader.init
	// overflows when subtracting from the archive size, causing
	// the pre-allocation check to be bypassed.
	data := []byte{
		0x50, 0x4b, 0x06, 0x06, 0x05, 0x06, 0x31, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x50, 0x4b,

}

// Write writes to the current file in the tar archive.
// Write returns the error [ErrWriteTooLong] if more than
// Header.Size bytes are written after [Writer.WriteHeader].
//
// Calling Write on special types like [TypeLink], [TypeSymlink], [TypeChar],
// [TypeBlock], [TypeDir], and [TypeFifo] returns (0, [ErrWriteTooLong]) regardless
// of what the [Header.Size] claims.