LLDB  mainline
VASprintf.cpp
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1 //===-- VASPrintf.cpp -------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
10 
11 #include "llvm/ADT/SmallString.h"
12 #include "llvm/ADT/SmallVector.h"
13 #include "llvm/ADT/StringRef.h"
14 
15 #include <assert.h>
16 #include <stdarg.h>
17 #include <stdio.h>
18 
20  va_list args) {
21  llvm::SmallString<16> error("<Encoding error>");
22  bool result = true;
23 
24  // Copy in case our first call to vsnprintf doesn't fit into our buffer
25  va_list copy_args;
26  va_copy(copy_args, args);
27 
28  buf.resize(buf.capacity());
29  // Write up to `capacity` bytes, ignoring the current size.
30  int length = ::vsnprintf(buf.data(), buf.size(), fmt, args);
31  if (length < 0) {
32  buf = error;
33  result = false;
34  goto finish;
35  }
36 
37  if (size_t(length) >= buf.size()) {
38  // The error formatted string didn't fit into our buffer, resize it to the
39  // exact needed size, and retry
40  buf.resize(length + 1);
41  length = ::vsnprintf(buf.data(), buf.size(), fmt, copy_args);
42  if (length < 0) {
43  buf = error;
44  result = false;
45  goto finish;
46  }
47  assert(size_t(length) < buf.size());
48  }
49  buf.resize(length);
50 
51 finish:
52  va_end(args);
53  va_end(copy_args);
54  return result;
55 }
bool VASprintf(llvm::SmallVectorImpl< char > &buf, const char *fmt, va_list args)
Definition: VASprintf.cpp:19