> On 8 Mar 2018, at 11:21, Toke Høiland-Jørgensen <t...@toke.dk> wrote: > >> >> Oh and curiously the bad values go away if you ask for json output >> it’s much better. Which rather points at a ‘feature’ of the >> ‘print_string’ behaviour. > > Right. Well, the print_* functions are behind several levels of > pre-processor indirection, so not quite obvious what's going on here. > Don't really see why they should spit out garbage values, though. > > > Stephen, do you have any ideas? > > -Toke
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Right, cracked it and it’s horrible! print_uint is expanded thus: Note the type of value uint64_t void print_color_uint(enum output_type t, enum color_attr color, const char *key, const char *fmt, uint64_t value); static inline void print_uint (enum output_type t, const char *key, const char *fmt, uint64_t value) { print_color_uint( t, COLOR_NONE, key, fmt, value); }; So far so good. print_color_uint expands to: void print_color_uint(enum output_type t, enum color_attr color, const char *key, const char *fmt, uint64_t value) { if (((t & PRINT_JSON || t & PRINT_ANY) && _jw)) { if (!key) jsonw_uint(_jw, value); else jsonw_uint_field(_jw, key, value); } else if ((!_jw && (t & PRINT_FP || t & PRINT_ANY))) { color_fprintf( (stdout) , color, fmt, value); } }; Again, no issue and we eventually call color_fprintf int color_fprintf(FILE *fp, enum color_attr attr, const char *fmt, ...) { int ret = 0; va_list args; va_start(args, fmt); if (!color_is_enabled || attr == COLOR_NONE) { ret = vfprintf(fp, fmt, args); goto end; } Now, color_printf is a variable argument list function and as such is dependent upon being told the correct size of argument variables in the fmt variable. And that’s our problem, we’re passing a 64bit integer but telling the format string that it’s ‘int’…which I’m guessing can be variable sizes depending on architecture, as can the endianness. If we instead do (in q_cake.c) #include <inttypes.h> print_uint(PRINT_ANY, "min_transport_size", " min/max transport layer size: %10" PRIu64, stnc->min_trnlen); it works. This needs sanity checking by a clever person. Cheers, Kevin D-B 012C ACB2 28C6 C53E 9775 9123 B3A2 389B 9DE2 334A
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