diff options
| author | John Hemmick <33430538+hemmick@users.noreply.github.com> | 2019-11-05 23:43:02 +0300 |
|---|---|---|
| committer | Christopher Haster <chaster@utexas.edu> | 2020-03-30 05:58:49 +0300 |
| commit | 6372f515fe59616bd7e00ca7bcce762c05ab029b (patch) | |
| tree | e8e044c70dd44a7e168c3c7056465645f2378778 | |
| parent | 6b65737715039ef92d348014316b575b52547019 (diff) | |
Allow debug prints without __VA_ARGS__
__VA_ARGS__ are frustrating in C. Even for their main purpose (printf),
they fall short in that they don't have a _portable_ way to have zero
arguments after the format string in a printf call.
Even if we detect compilers and use ##__VA_ARGS__ where available, GCC
emits a warning with -pedantic that is _impossible_ to explicitly
disable.
This commit contains the best solution we can think of. A bit of
indirection that adds a hidden "%s" % "" to the end of the format
string. This solution does not work everywhere as it has a runtime
cost, but it is hopefully ok for debug statements.
| -rw-r--r-- | lfs_util.h | 28 |
1 files changed, 16 insertions, 12 deletions
@@ -50,31 +50,35 @@ extern "C" // Logging functions #ifdef LFS_YES_TRACE -#define LFS_TRACE(fmt, ...) \ - printf("lfs_trace:%d: " fmt "\n", __LINE__, __VA_ARGS__) +#define LFS_TRACE_(fmt, ...) \ + printf("lfs_trace:%d: " fmt "%s\n", __LINE__, __VA_ARGS__) +#define LFS_TRACE(...) LFS_TRACE_(__VA_ARGS__, "") #else -#define LFS_TRACE(fmt, ...) +#define LFS_TRACE(...) #endif #ifndef LFS_NO_DEBUG -#define LFS_DEBUG(fmt, ...) \ - printf("lfs_debug:%d: " fmt "\n", __LINE__, __VA_ARGS__) +#define LFS_DEBUG_(fmt, ...) \ + printf("lfs_debug:%d: " fmt "%s\n", __LINE__, __VA_ARGS__) +#define LFS_DEBUG(...) LFS_DEBUG_(__VA_ARGS__, "") #else -#define LFS_DEBUG(fmt, ...) +#define LFS_DEBUG(...) #endif #ifndef LFS_NO_WARN -#define LFS_WARN(fmt, ...) \ - printf("lfs_warn:%d: " fmt "\n", __LINE__, __VA_ARGS__) +#define LFS_WARN_(fmt, ...) \ + printf("lfs_warn:%d: " fmt "%s\n", __LINE__, __VA_ARGS__) +#define LFS_WARN(...) LFS_WARN_(__VA_ARGS__, "") #else -#define LFS_WARN(fmt, ...) +#define LFS_WARN(...) #endif #ifndef LFS_NO_ERROR -#define LFS_ERROR(fmt, ...) \ - printf("lfs_error:%d: " fmt "\n", __LINE__, __VA_ARGS__) +#define LFS_ERROR_(fmt, ...) \ + printf("lfs_error:%d: " fmt "%s\n", __LINE__, __VA_ARGS__) +#define LFS_ERROR(...) LFS_ERROR_(__VA_ARGS__, "") #else -#define LFS_ERROR(fmt, ...) +#define LFS_ERROR(...) #endif // Runtime assertions |