1 2 #ifndef HAVE_VPRINTF 3 #include "choke-me: no vprintf and no snprintf" 4 choke me. 5 #endif 6 7 #if defined(HAVE_STDARG_H) 8 # include <stdarg.h> 9 # ifndef VA_START 10 # define VA_START(a, f) va_start(a, f) 11 # define VA_END(a) va_end(a) 12 # endif /* VA_START */ 13 # define SNV_USING_STDARG_H 14 15 #elif defined(HAVE_VARARGS_H) 16 # include <varargs.h> 17 # ifndef VA_START 18 # define VA_START(a, f) va_start(a) 19 # define VA_END(a) va_end(a) 20 # endif /* VA_START */ 21 # undef SNV_USING_STDARG_H 22 23 #else 24 # include "must-have-stdarg-or-varargs" 25 choke me. 26 #endif 27 28 static int 29 snprintf(char *str, size_t n, char const *fmt, ...) 30 { 31 va_list ap; 32 int rval; 33 34 #ifdef VSPRINTF_CHARSTAR 35 char *rp; 36 VA_START(ap, fmt); 37 rp = vsprintf(str, fmt, ap); 38 VA_END(ap); 39 rval = strlen(rp); 40 41 #else 42 VA_START(ap, fmt); 43 rval = vsprintf(str, fmt, ap); 44 VA_END(ap); 45 #endif 46 47 if (rval > n) { 48 fprintf(stderr, "snprintf buffer overrun %d > %d\n", rval, (int)n); 49 abort(); 50 } 51 return rval; 52 } 53 54 static int 55 vsnprintf( char *str, size_t n, char const *fmt, va_list ap ) 56 { 57 #ifdef VSPRINTF_CHARSTAR 58 return (strlen(vsprintf(str, fmt, ap))); 59 #else 60 return (vsprintf(str, fmt, ap)); 61 #endif 62 } 63