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Ben Burdette 2020-06-04 11:53:19 -06:00
parent 721943e1d4
commit 94427ffee3
3 changed files with 42 additions and 18 deletions
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6
src/libutil/error.cc
View file

@ -10,13 +10,16 @@ namespace nix {
const std::string nativeSystem = SYSTEM;
// addPrefix is used for show-trace. Strings added with addPrefix
// will print ahead of the error itself.
BaseError & BaseError::addPrefix(const FormatOrString & fs)
{
prefix_ = fs.s + prefix_;
return *this;
}
// c++ std::exception descendants must have a 'const char* what()' function.
// This stringifies the error and caches it for use by what(), or similarly by msg().
const string& BaseError::calcWhat() const
{
if (what_.has_value())
@ -53,6 +56,7 @@ string showErrPos(const ErrPos &errPos)
}
}
// if nixCode contains lines of code, print them to the ostream, indicating the error column.
void printCodeLines(std::ostream &out, const string &prefix, const NixCode &nixCode)
{
// previous line of code.

21
src/libutil/error.hh
View file

@ -22,6 +22,23 @@
namespace nix {
/*
This file defines two main structs/classes used in nix error handling.
ErrorInfo provides a standard payload of error information, with conversion to string
happening in the logger rather than at the call site.
BaseError is the ancestor of nix specific exceptions (and Interrupted), and contains
an ErrorInfo.
ErrorInfo structs are sent to the logger as part of an exception, or directly with the
logError or logWarning macros.
See the error-demo.cc program for usage examples.
*/
typedef enum {
lvlError = 0,
lvlWarn,
@ -32,6 +49,7 @@ typedef enum {
lvlVomit
} Verbosity;
// ErrPos indicates the location of an error in a nix file.
struct ErrPos {
int line = 0;
int column = 0;
@ -42,6 +60,7 @@ struct ErrPos {
return line != 0;
}
// convert from the Pos struct, found in libexpr.
template <class P>
ErrPos& operator=(const P &pos)
{
@ -65,8 +84,6 @@ struct NixCode {
std::optional<string> nextLineOfCode;
};
// -------------------------------------------------
// ErrorInfo.
struct ErrorInfo {
Verbosity level;
string name;

33
src/libutil/logging.hh
View file

@ -150,9 +150,23 @@ bool handleJSONLogMessage(const std::string & msg,
extern Verbosity verbosity; /* suppress msgs > this */
/* Print a message if the current log level is at least the specified
level. Note that this has to be implemented as a macro to ensure
that the arguments are evaluated lazily. */
/* Print a message with the standard ErrorInfo format.
In general, use these 'log' macros for reporting problems that may require user
intervention or that need more explanation. Use the 'print' macros for more
lightweight status messages. */
#define logErrorInfo(level, errorInfo...) \
do { \
if (level <= nix::verbosity) { \
logger->logEI(level, errorInfo); \
} \
} while (0)
#define logError(errorInfo...) logErrorInfo(lvlError, errorInfo)
#define logWarning(errorInfo...) logErrorInfo(lvlWarn, errorInfo)
/* Print a string message if the current log level is at least the specified
level. Note that this has to be implemented as a macro to ensure that the
arguments are evaluated lazily. */
#define printMsg(level, args...) \
do { \
if (level <= nix::verbosity) { \
@ -166,18 +180,7 @@ extern Verbosity verbosity; /* suppress msgs > this */
#define debug(args...) printMsg(lvlDebug, args)
#define vomit(args...) printMsg(lvlVomit, args)
#define logErrorInfo(level, errorInfo...) \
do { \
if (level <= nix::verbosity) { \
logger->logEI(level, errorInfo); \
} \
} while (0)
#define logError(errorInfo...) logErrorInfo(lvlError, errorInfo)
#define logWarning(errorInfo...) logErrorInfo(lvlWarn, errorInfo)
/* if verbosity >= lvlWarn, print a message with a yellow 'warning:' prefix. */
template<typename... Args>
inline void warn(const std::string & fs, const Args & ... args)
{