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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* Provides a safer sprintf for printing to fixed-size character arrays. */
#ifndef mozilla_Sprintf_h_
#define mozilla_Sprintf_h_
#include <stdio.h>
#include <stdarg.h>
#include <algorithm>
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/Printf.h"
#ifdef __cplusplus
# ifndef SPRINTF_H_USES_VSNPRINTF
namespace mozilla {
namespace detail {
struct MOZ_STACK_CLASS SprintfAppend final : public mozilla::PrintfTarget {
explicit SprintfAppend(char* aBuf, size_t aBufLen)
: mBuf(aBuf), mBufLen(aBufLen) {}
bool append(const char* aStr, size_t aLen) override {
if (aLen == 0) {
return true;
}
// Don't copy more than what's left to use.
size_t copy = std::min(mBufLen, aLen);
if (copy > 0) {
memcpy(mBuf, aStr, copy);
mBuf += copy;
mBufLen -= copy;
}
return true;
}
private:
char* mBuf;
size_t mBufLen;
};
} // namespace detail
} // namespace mozilla
# endif // SPRINTF_H_USES_VSNPRINTF
MOZ_FORMAT_PRINTF(3, 0)
MOZ_MAYBE_UNUSED
static int VsprintfBuf(char* buffer, size_t bufsize, const char* format,
va_list args) {
MOZ_ASSERT(format != buffer);
# ifdef SPRINTF_H_USES_VSNPRINTF
int result = vsnprintf(buffer, bufsize, format, args);
buffer[bufsize - 1] = '\0';
return result;
# else
mozilla::detail::SprintfAppend ss(buffer, bufsize);
ss.vprint(format, args);
size_t len = ss.emitted();
buffer[std::min(len, bufsize - 1)] = '\0';
return len;
# endif
}
MOZ_FORMAT_PRINTF(3, 4)
MOZ_MAYBE_UNUSED
static int SprintfBuf(char* buffer, size_t bufsize, const char* format, ...) {
va_list args;
va_start(args, format);
int result = VsprintfBuf(buffer, bufsize, format, args);
va_end(args);
return result;
}
template <size_t N>
MOZ_FORMAT_PRINTF(2, 0)
int VsprintfLiteral(char (&buffer)[N], const char* format, va_list args) {
return VsprintfBuf(buffer, N, format, args);
}
template <size_t N>
MOZ_FORMAT_PRINTF(2, 3)
int SprintfLiteral(char (&buffer)[N], const char* format, ...) {
va_list args;
va_start(args, format);
int result = VsprintfLiteral(buffer, format, args);
va_end(args);
return result;
}
#endif
#endif /* mozilla_Sprintf_h_ */