This is useful to see where trace output came from. Add 'const char *file, int line' parameters to the printing functions and rename them to *_fl.
Add trace_printf* and trace_strbuf macros resolving to the *_fl functions and let the preprocessor fill in __FILE__ and __LINE__. As the trace_printf* functions take a variable number of arguments, this requires variadic macros (i.e. '#define foo(...) foo_impl(__VA_ARGS__)'. Though part of C99, it is unclear whether older compilers support this. Thus keep the old functions and only enable variadic macros for GNUC and MSVC 2005+ (_MSC_VER 1400). This has the nice side effect that the old C-style declarations serve as documentation how the macros are to be used. Print 'file:line ' as prefix to each trace line. Align the remaining trace output at column 40 to accommodate 18 char file names + 4 digit line number (currently there are 30 *.c files of length 18 and just 11 of 19). Trace output from longer source files (e.g. builtin/receive-pack.c) will not be aligned. Signed-off-by: Karsten Blees <bl...@dcon.de> --- git-compat-util.h | 4 ++++ trace.c | 72 +++++++++++++++++++++++++++++++++++++++++++++---------- trace.h | 54 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 118 insertions(+), 12 deletions(-) diff --git a/git-compat-util.h b/git-compat-util.h index b6f03b3..4dd065d 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -704,6 +704,10 @@ void git_qsort(void *base, size_t nmemb, size_t size, #endif #endif +#if defined(__GNUC__) || (_MSC_VER >= 1400) +#define HAVE_VARIADIC_MACROS 1 +#endif + /* * Preserves errno, prints a message, but gives no warning for ENOENT. * Always returns the return value of unlink(2). diff --git a/trace.c b/trace.c index e8ce619..f013958 100644 --- a/trace.c +++ b/trace.c @@ -85,7 +85,8 @@ void trace_disable(struct trace_key *key) static const char err_msg[] = "Could not trace into fd given by " "GIT_TRACE environment variable"; -static int prepare_trace_line(struct trace_key *key, struct strbuf *buf) +static int prepare_trace_line(const char *file, int line, + struct trace_key *key, struct strbuf *buf) { static struct trace_key trace_bare = TRACE_KEY_INIT(BARE); struct timeval tv; @@ -108,6 +109,14 @@ static int prepare_trace_line(struct trace_key *key, struct strbuf *buf) strbuf_addf(buf, "%02d:%02d:%02d.%06ld ", tm.tm_hour, tm.tm_min, tm.tm_sec, (long) tv.tv_usec); +#ifdef HAVE_VARIADIC_MACROS + /* print file:line */ + strbuf_addf(buf, "%s:%d ", file, line); + /* align trace output (column 40 catches most files names in git) */ + while (buf->len < 40) + strbuf_addch(buf, ' '); +#endif + return 1; } @@ -121,49 +130,52 @@ static void print_trace_line(struct trace_key *key, struct strbuf *buf) strbuf_release(buf); } -static void trace_vprintf(struct trace_key *key, const char *format, va_list ap) +static void trace_vprintf_fl(const char *file, int line, struct trace_key *key, + const char *format, va_list ap) { struct strbuf buf = STRBUF_INIT; - if (!prepare_trace_line(key, &buf)) + if (!prepare_trace_line(file, line, key, &buf)) return; strbuf_vaddf(&buf, format, ap); print_trace_line(key, &buf); } -void trace_argv_printf(const char **argv, const char *format, ...) +static void trace_argv_vprintf_fl(const char *file, int line, + const char **argv, const char *format, + va_list ap) { struct strbuf buf = STRBUF_INIT; - va_list ap; - if (!prepare_trace_line(NULL, &buf)) + if (!prepare_trace_line(file, line, NULL, &buf)) return; - va_start(ap, format); strbuf_vaddf(&buf, format, ap); - va_end(ap); sq_quote_argv(&buf, argv, 0); print_trace_line(NULL, &buf); } -void trace_strbuf(struct trace_key *key, const struct strbuf *data) +void trace_strbuf_fl(const char *file, int line, struct trace_key *key, + const struct strbuf *data) { struct strbuf buf = STRBUF_INIT; - if (!prepare_trace_line(key, &buf)) + if (!prepare_trace_line(file, line, key, &buf)) return; strbuf_addbuf(&buf, data); print_trace_line(key, &buf); } +#ifndef HAVE_VARIADIC_MACROS + void trace_printf(const char *format, ...) { va_list ap; va_start(ap, format); - trace_vprintf(NULL, format, ap); + trace_vprintf_fl(NULL, 0, NULL, format, ap); va_end(ap); } @@ -171,10 +183,46 @@ void trace_printf_key(struct trace_key *key, const char *format, ...) { va_list ap; va_start(ap, format); - trace_vprintf(key, format, ap); + trace_vprintf_fl(NULL, 0, key, format, ap); + va_end(ap); +} + +void trace_argv_printf(const char **argv, const char *format, ...) +{ + va_list ap; + va_start(ap, format); + trace_argv_vprintf_fl(NULL, 0, argv, format, ap); va_end(ap); } +void trace_strbuf(const char *key, const struct strbuf *data) +{ + trace_strbuf_fl(NULL, 0, key, data); +} + +#else + +void trace_printf_key_fl(const char *file, int line, struct trace_key *key, + const char *format, ...) +{ + va_list ap; + va_start(ap, format); + trace_vprintf_fl(file, line, key, format, ap); + va_end(ap); +} + +void trace_argv_printf_fl(const char *file, int line, const char **argv, + const char *format, ...) +{ + va_list ap; + va_start(ap, format); + trace_argv_vprintf_fl(file, line, argv, format, ap); + va_end(ap); +} + +#endif /* HAVE_VARIADIC_MACROS */ + + static const char *quote_crnl(const char *path) { static char new_path[PATH_MAX]; diff --git a/trace.h b/trace.h index 0c98da2..c3ca47c 100644 --- a/trace.h +++ b/trace.h @@ -17,6 +17,8 @@ extern void trace_repo_setup(const char *prefix); extern int trace_want(struct trace_key *key); extern void trace_disable(struct trace_key *key); +#ifndef HAVE_VARIADIC_MACROS + __attribute__((format (printf, 1, 2))) extern void trace_printf(const char *format, ...); @@ -28,4 +30,56 @@ extern void trace_argv_printf(const char **argv, const char *format, ...); extern void trace_strbuf(struct trace_key *key, const struct strbuf *data); +#else + +/* + * Macros to add file:line - see above for C-style declarations of how these + * should be used. + * + * TRACE_CONTEXT may be set to __FUNCTION__ if the compiler supports it. The + * default is __FILE__, as it is consistent with assert(), and static function + * names are not necessarily unique. + */ +#define TRACE_CONTEXT __FILE__ + +/* + * Note: with C99 variadic macros, __VA_ARGS__ must include the last fixed + * parameter ('format' in this case). Otherwise, a call without variable + * arguments will have a surplus ','. E.g.: + * + * #define foo(format, ...) bar(format, __VA_ARGS__) + * foo("test"); + * + * will expand to + * + * bar("test",); + * + * which is invalid (note the ',)'). With GNUC, '##__VA_ARGS__' drops the + * comma, but this is non-standard. + */ + +#define trace_printf(...) \ + trace_printf_key_fl(TRACE_CONTEXT, __LINE__, NULL, __VA_ARGS__) + +#define trace_printf_key(key, ...) \ + trace_printf_key_fl(TRACE_CONTEXT, __LINE__, key, __VA_ARGS__) + +#define trace_argv_printf(argv, ...) \ + trace_argv_printf_fl(TRACE_CONTEXT, __LINE__, argv, __VA_ARGS__) + +#define trace_strbuf(key, data) \ + trace_strbuf_fl(TRACE_CONTEXT, __LINE__, key, data) + +/* backend functions, use non-*fl macros instead */ +__attribute__((format (printf, 4, 5))) +extern void trace_printf_key_fl(const char *file, int line, struct trace_key *key, + const char *format, ...); +__attribute__((format (printf, 4, 5))) +extern void trace_argv_printf_fl(const char *file, int line, const char **argv, + const char *format, ...); +extern void trace_strbuf_fl(const char *file, int line, struct trace_key *key, + const struct strbuf *data); + +#endif /* HAVE_VARIADIC_MACROS */ + #endif /* TRACE_H */ -- 2.0.0.406.ge74f8ff -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html