Tracing macros

[DimitriPapadopoulos]

Describe the bug

I am not sure I understand the tracing macros:

c-blosc2/include/blosc2.h

Lines 114 to 129 in 3ae32b6

	#define BLOSC_ERROR(rc) \
	do { \
	int rc_ = rc; \
	if (rc_ < BLOSC2_ERROR_SUCCESS) { \
	char *error_msg = print_error(rc_); \
	BLOSC_TRACE_ERROR("%s", error_msg); \
	return rc_; \
	} \
	} while (0)
	#define BLOSC_INFO(msg, ...) \
	do { \
	const char *__e = getenv("BLOSC_INFO"); \
	if (!__e) { break; } \
	fprintf(stderr, "[INFO] - " msg "\n", ##__VA_ARGS__); \
	} while(0)

• BLOSC_ERROR calls BLOSC_TRACE_ERROR, which prints only if environment variable BLOSC_TRACE is defined
• BLOSC_INFO prints directly if environment variable BLOSC_INFO is defined. Instead, I think it should call BLOSC_TRACE_INFO, which prints only if environment variable BLOSC_TRACE is defined.

I realise that it's probably unfeasible to modify things without slightly breaking backwards compatibility, but the current macros don't make sense to me: if environment only variable BLOSC_INFO is defined, BLOSC_INFO will print but BLOSC_ERROR will not print!

[FrancescAlted]

I like your proposal of making interfaces more uniform. Right now BLOSC_INFO should not be used beyond developers, so I don't think we will break anything serious if we implement what you are proposing. Would you mind sending a PR?