/////////////////////////////////////////////////////////////////////////////// // \author (c) Marco Paland (info@paland.com) // 2014-2019, PALANDesign Hannover, Germany // // \license The MIT License (MIT) // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to deal // in the Software without restriction, including without limitation the rights // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell // copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN // THE SOFTWARE. // // \brief Tiny printf, sprintf and (v)snprintf implementation, optimized for speed on // embedded systems with a very limited resources. These routines are thread // safe and reentrant! // Use this instead of the bloated standard/newlib printf cause these use // malloc for printf (and may not be thread safe). // /////////////////////////////////////////////////////////////////////////////// /*Original repository: https://github.com/mpaland/printf*/ #include "lv_printf.h" #if LV_SPRINTF_CUSTOM == 0 #include #define PRINTF_DISABLE_SUPPORT_FLOAT (!LV_SPRINTF_USE_FLOAT) // 'ntoa' conversion buffer size, this must be big enough to hold one converted // numeric number including padded zeros (dynamically created on stack) // default: 32 byte #ifndef PRINTF_NTOA_BUFFER_SIZE #define PRINTF_NTOA_BUFFER_SIZE 32U #endif // 'ftoa' conversion buffer size, this must be big enough to hold one converted // float number including padded zeros (dynamically created on stack) // default: 32 byte #ifndef PRINTF_FTOA_BUFFER_SIZE #define PRINTF_FTOA_BUFFER_SIZE 32U #endif // support for the floating point type (%f) // default: activated #if !PRINTF_DISABLE_SUPPORT_FLOAT #define PRINTF_SUPPORT_FLOAT #endif // support for exponential floating point notation (%e/%g) // default: activated #ifndef PRINTF_DISABLE_SUPPORT_EXPONENTIAL #define PRINTF_SUPPORT_EXPONENTIAL #endif // define the default floating point precision // default: 6 digits #ifndef PRINTF_DEFAULT_FLOAT_PRECISION #define PRINTF_DEFAULT_FLOAT_PRECISION 6U #endif // define the largest float suitable to print with %f // default: 1e9 #ifndef PRINTF_MAX_FLOAT #define PRINTF_MAX_FLOAT 1e9 #endif // support for the long long types (%llu or %p) // default: activated #ifndef PRINTF_DISABLE_SUPPORT_LONG_LONG #define PRINTF_SUPPORT_LONG_LONG #endif // support for the ptrdiff_t type (%t) // ptrdiff_t is normally defined in as long or long long type // default: activated #ifndef PRINTF_DISABLE_SUPPORT_PTRDIFF_T #define PRINTF_SUPPORT_PTRDIFF_T #endif /////////////////////////////////////////////////////////////////////////////// // internal flag definitions #define FLAGS_ZEROPAD (1U << 0U) #define FLAGS_LEFT (1U << 1U) #define FLAGS_PLUS (1U << 2U) #define FLAGS_SPACE (1U << 3U) #define FLAGS_HASH (1U << 4U) #define FLAGS_UPPERCASE (1U << 5U) #define FLAGS_CHAR (1U << 6U) #define FLAGS_SHORT (1U << 7U) #define FLAGS_LONG (1U << 8U) #define FLAGS_LONG_LONG (1U << 9U) #define FLAGS_PRECISION (1U << 10U) #define FLAGS_ADAPT_EXP (1U << 11U) // import float.h for DBL_MAX #if defined(PRINTF_SUPPORT_FLOAT) #include #endif // output function type typedef void (*out_fct_type)(char character, void * buffer, size_t idx, size_t maxlen); // wrapper (used as buffer) for output function type typedef struct { void (*fct)(char character, void * arg); void * arg; } out_fct_wrap_type; // internal buffer output static inline void _out_buffer(char character, void * buffer, size_t idx, size_t maxlen) { if(idx < maxlen) { ((char *)buffer)[idx] = character; } } // internal null output static inline void _out_null(char character, void * buffer, size_t idx, size_t maxlen) { LV_UNUSED(character); LV_UNUSED(buffer); LV_UNUSED(idx); LV_UNUSED(maxlen); } // internal secure strlen // \return The length of the string (excluding the terminating 0) limited by 'maxsize' static inline unsigned int _strnlen_s(const char * str, size_t maxsize) { const char * s; for(s = str; *s && maxsize--; ++s); return (unsigned int)(s - str); } // internal test if char is a digit (0-9) // \return true if char is a digit static inline bool _is_digit(char ch) { return (ch >= '0') && (ch <= '9'); } // internal ASCII string to unsigned int conversion static unsigned int _atoi(const char ** str) { unsigned int i = 0U; while(_is_digit(**str)) { i = i * 10U + (unsigned int)(*((*str)++) - '0'); } return i; } // output the specified string in reverse, taking care of any zero-padding static size_t _out_rev(out_fct_type out, char * buffer, size_t idx, size_t maxlen, const char * buf, size_t len, unsigned int width, unsigned int flags) { const size_t start_idx = idx; // pad spaces up to given width if(!(flags & FLAGS_LEFT) && !(flags & FLAGS_ZEROPAD)) { size_t i; for(i = len; i < width; i++) { out(' ', buffer, idx++, maxlen); } } // reverse string while(len) { out(buf[--len], buffer, idx++, maxlen); } // append pad spaces up to given width if(flags & FLAGS_LEFT) { while(idx - start_idx < width) { out(' ', buffer, idx++, maxlen); } } return idx; } // internal itoa format static size_t _ntoa_format(out_fct_type out, char * buffer, size_t idx, size_t maxlen, char * buf, size_t len, bool negative, unsigned int base, unsigned int prec, unsigned int width, unsigned int flags) { // pad leading zeros if(!(flags & FLAGS_LEFT)) { if(width && (flags & FLAGS_ZEROPAD) && (negative || (flags & (FLAGS_PLUS | FLAGS_SPACE)))) { width--; } while((len < prec) && (len < PRINTF_NTOA_BUFFER_SIZE)) { buf[len++] = '0'; } while((flags & FLAGS_ZEROPAD) && (len < width) && (len < PRINTF_NTOA_BUFFER_SIZE)) { buf[len++] = '0'; } } // handle hash if(flags & FLAGS_HASH) { if(!(flags & FLAGS_PRECISION) && len && ((len == prec) || (len == width))) { len--; if(len && (base == 16U)) { len--; } } if((base == 16U) && !(flags & FLAGS_UPPERCASE) && (len < PRINTF_NTOA_BUFFER_SIZE)) { buf[len++] = 'x'; } else if((base == 16U) && (flags & FLAGS_UPPERCASE) && (len < PRINTF_NTOA_BUFFER_SIZE)) { buf[len++] = 'X'; } else if((base == 2U) && (len < PRINTF_NTOA_BUFFER_SIZE)) { buf[len++] = 'b'; } if(len < PRINTF_NTOA_BUFFER_SIZE) { buf[len++] = '0'; } } if(len < PRINTF_NTOA_BUFFER_SIZE) { if(negative) { buf[len++] = '-'; } else if(flags & FLAGS_PLUS) { buf[len++] = '+'; // ignore the space if the '+' exists } else if(flags & FLAGS_SPACE) { buf[len++] = ' '; } } return _out_rev(out, buffer, idx, maxlen, buf, len, width, flags); } // internal itoa for 'long' type static size_t _ntoa_long(out_fct_type out, char * buffer, size_t idx, size_t maxlen, unsigned long value, bool negative, unsigned long base, unsigned int prec, unsigned int width, unsigned int flags) { char buf[PRINTF_NTOA_BUFFER_SIZE]; size_t len = 0U; // no hash for 0 values if(!value) { flags &= ~FLAGS_HASH; } // write if precision != 0 and value is != 0 if(!(flags & FLAGS_PRECISION) || value) { do { const char digit = (char)(value % base); buf[len++] = digit < 10 ? '0' + digit : (flags & FLAGS_UPPERCASE ? 'A' : 'a') + digit - 10; value /= base; } while(value && (len < PRINTF_NTOA_BUFFER_SIZE)); } return _ntoa_format(out, buffer, idx, maxlen, buf, len, negative, (unsigned int)base, prec, width, flags); } // internal itoa for 'long long' type #if defined(PRINTF_SUPPORT_LONG_LONG) static size_t _ntoa_long_long(out_fct_type out, char * buffer, size_t idx, size_t maxlen, unsigned long long value, bool negative, unsigned long long base, unsigned int prec, unsigned int width, unsigned int flags) { char buf[PRINTF_NTOA_BUFFER_SIZE]; size_t len = 0U; // no hash for 0 values if(!value) { flags &= ~FLAGS_HASH; } // write if precision != 0 and value is != 0 if(!(flags & FLAGS_PRECISION) || value) { do { const char digit = (char)(value % base); buf[len++] = digit < 10 ? '0' + digit : (flags & FLAGS_UPPERCASE ? 'A' : 'a') + digit - 10; value /= base; } while(value && (len < PRINTF_NTOA_BUFFER_SIZE)); } return _ntoa_format(out, buffer, idx, maxlen, buf, len, negative, (unsigned int)base, prec, width, flags); } #endif // PRINTF_SUPPORT_LONG_LONG #if defined(PRINTF_SUPPORT_FLOAT) #if defined(PRINTF_SUPPORT_EXPONENTIAL) // forward declaration so that _ftoa can switch to exp notation for values > PRINTF_MAX_FLOAT static size_t _etoa(out_fct_type out, char * buffer, size_t idx, size_t maxlen, double value, unsigned int prec, unsigned int width, unsigned int flags); #endif // internal ftoa for fixed decimal floating point static size_t _ftoa(out_fct_type out, char * buffer, size_t idx, size_t maxlen, double value, unsigned int prec, unsigned int width, unsigned int flags) { char buf[PRINTF_FTOA_BUFFER_SIZE]; size_t len = 0U; double diff = 0.0; // powers of 10 static const double pow10[] = { 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000 }; // test for special values if(value != value) return _out_rev(out, buffer, idx, maxlen, "nan", 3, width, flags); if(value < -DBL_MAX) return _out_rev(out, buffer, idx, maxlen, "fni-", 4, width, flags); if(value > DBL_MAX) return _out_rev(out, buffer, idx, maxlen, (flags & FLAGS_PLUS) ? "fni+" : "fni", (flags & FLAGS_PLUS) ? 4U : 3U, width, flags); // test for very large values // standard printf behavior is to print EVERY whole number digit -- which could be 100s of characters overflowing your buffers == bad if((value > PRINTF_MAX_FLOAT) || (value < -PRINTF_MAX_FLOAT)) { #if defined(PRINTF_SUPPORT_EXPONENTIAL) return _etoa(out, buffer, idx, maxlen, value, prec, width, flags); #else return 0U; #endif } // test for negative bool negative = false; if(value < 0) { negative = true; value = 0 - value; } // set default precision, if not set explicitly if(!(flags & FLAGS_PRECISION)) { prec = PRINTF_DEFAULT_FLOAT_PRECISION; } // limit precision to 9, cause a prec >= 10 can lead to overflow errors while((len < PRINTF_FTOA_BUFFER_SIZE) && (prec > 9U)) { buf[len++] = '0'; prec--; } int whole = (int)value; double tmp = (value - whole) * pow10[prec]; unsigned long frac = (unsigned long)tmp; diff = tmp - frac; if(diff > 0.5) { ++frac; // handle rollover, e.g. case 0.99 with prec 1 is 1.0 if(frac >= pow10[prec]) { frac = 0; ++whole; } } else if(diff < 0.5) { } else if((frac == 0U) || (frac & 1U)) { // if halfway, round up if odd OR if last digit is 0 ++frac; } if(prec == 0U) { diff = value - (double)whole; if((!(diff < 0.5) || (diff > 0.5)) && (whole & 1)) { // exactly 0.5 and ODD, then round up // 1.5 -> 2, but 2.5 -> 2 ++whole; } } else { unsigned int count = prec; // now do fractional part, as an unsigned number while(len < PRINTF_FTOA_BUFFER_SIZE) { --count; buf[len++] = (char)(48U + (frac % 10U)); if(!(frac /= 10U)) { break; } } // add extra 0s while((len < PRINTF_FTOA_BUFFER_SIZE) && (count-- > 0U)) { buf[len++] = '0'; } if(len < PRINTF_FTOA_BUFFER_SIZE) { // add decimal buf[len++] = '.'; } } // do whole part, number is reversed while(len < PRINTF_FTOA_BUFFER_SIZE) { buf[len++] = (char)(48 + (whole % 10)); if(!(whole /= 10)) { break; } } // pad leading zeros if(!(flags & FLAGS_LEFT) && (flags & FLAGS_ZEROPAD)) { if(width && (negative || (flags & (FLAGS_PLUS | FLAGS_SPACE)))) { width--; } while((len < width) && (len < PRINTF_FTOA_BUFFER_SIZE)) { buf[len++] = '0'; } } if(len < PRINTF_FTOA_BUFFER_SIZE) { if(negative) { buf[len++] = '-'; } else if(flags & FLAGS_PLUS) { buf[len++] = '+'; // ignore the space if the '+' exists } else if(flags & FLAGS_SPACE) { buf[len++] = ' '; } } return _out_rev(out, buffer, idx, maxlen, buf, len, width, flags); } #if defined(PRINTF_SUPPORT_EXPONENTIAL) // internal ftoa variant for exponential floating-point type, contributed by Martijn Jasperse static size_t _etoa(out_fct_type out, char * buffer, size_t idx, size_t maxlen, double value, unsigned int prec, unsigned int width, unsigned int flags) { // check for NaN and special values if((value != value) || (value > DBL_MAX) || (value < -DBL_MAX)) { return _ftoa(out, buffer, idx, maxlen, value, prec, width, flags); } // determine the sign const bool negative = value < 0; if(negative) { value = -value; } // default precision if(!(flags & FLAGS_PRECISION)) { prec = PRINTF_DEFAULT_FLOAT_PRECISION; } // determine the decimal exponent // based on the algorithm by David Gay (https://www.ampl.com/netlib/fp/dtoa.c) union { uint64_t U; double F; } conv; conv.F = value; int exp2 = (int)((conv.U >> 52U) & 0x07FFU) - 1023; // effectively log2 conv.U = (conv.U & ((1ULL << 52U) - 1U)) | (1023ULL << 52U); // drop the exponent so conv.F is now in [1,2) // now approximate log10 from the log2 integer part and an expansion of ln around 1.5 int expval = (int)(0.1760912590558 + exp2 * 0.301029995663981 + (conv.F - 1.5) * 0.289529654602168); // now we want to compute 10^expval but we want to be sure it won't overflow exp2 = (int)(expval * 3.321928094887362 + 0.5); const double z = expval * 2.302585092994046 - exp2 * 0.6931471805599453; const double z2 = z * z; conv.U = (uint64_t)(exp2 + 1023) << 52U; // compute exp(z) using continued fractions, see https://en.wikipedia.org/wiki/Exponential_function#Continued_fractions_for_ex conv.F *= 1 + 2 * z / (2 - z + (z2 / (6 + (z2 / (10 + z2 / 14))))); // correct for rounding errors if(value < conv.F) { expval--; conv.F /= 10; } // the exponent format is "%+03d" and largest value is "307", so set aside 4-5 characters unsigned int minwidth = ((expval < 100) && (expval > -100)) ? 4U : 5U; // in "%g" mode, "prec" is the number of *significant figures* not decimals if(flags & FLAGS_ADAPT_EXP) { // do we want to fall-back to "%f" mode? if((value >= 1e-4) && (value < 1e6)) { if((int)prec > expval) { prec = (unsigned)((int)prec - expval - 1); } else { prec = 0; } flags |= FLAGS_PRECISION; // make sure _ftoa respects precision // no characters in exponent minwidth = 0U; expval = 0; } else { // we use one sigfig for the whole part if((prec > 0) && (flags & FLAGS_PRECISION)) { --prec; } } } // will everything fit? unsigned int fwidth = width; if(width > minwidth) { // we didn't fall-back so subtract the characters required for the exponent fwidth -= minwidth; } else { // not enough characters, so go back to default sizing fwidth = 0U; } if((flags & FLAGS_LEFT) && minwidth) { // if we're padding on the right, DON'T pad the floating part fwidth = 0U; } // rescale the float value if(expval) { value /= conv.F; } // output the floating part const size_t start_idx = idx; idx = _ftoa(out, buffer, idx, maxlen, negative ? -value : value, prec, fwidth, flags & ~FLAGS_ADAPT_EXP); // output the exponent part if(minwidth) { // output the exponential symbol out((flags & FLAGS_UPPERCASE) ? 'E' : 'e', buffer, idx++, maxlen); // output the exponent value idx = _ntoa_long(out, buffer, idx, maxlen, (expval < 0) ? -expval : expval, expval < 0, 10, 0, minwidth - 1, FLAGS_ZEROPAD | FLAGS_PLUS); // might need to right-pad spaces if(flags & FLAGS_LEFT) { while(idx - start_idx < width) out(' ', buffer, idx++, maxlen); } } return idx; } #endif // PRINTF_SUPPORT_EXPONENTIAL #endif // PRINTF_SUPPORT_FLOAT // internal vsnprintf static int _vsnprintf(out_fct_type out, char * buffer, const size_t maxlen, const char * format, va_list va) { unsigned int flags, width, precision, n; size_t idx = 0U; if(!buffer) { // use null output function out = _out_null; } while(*format) { // format specifier? %[flags][width][.precision][length] if(*format != '%') { // no out(*format, buffer, idx++, maxlen); format++; continue; } else { // yes, evaluate it format++; } // evaluate flags flags = 0U; do { switch(*format) { case '0': flags |= FLAGS_ZEROPAD; format++; n = 1U; break; case '-': flags |= FLAGS_LEFT; format++; n = 1U; break; case '+': flags |= FLAGS_PLUS; format++; n = 1U; break; case ' ': flags |= FLAGS_SPACE; format++; n = 1U; break; case '#': flags |= FLAGS_HASH; format++; n = 1U; break; default : n = 0U; break; } } while(n); // evaluate width field width = 0U; if(_is_digit(*format)) { width = _atoi(&format); } else if(*format == '*') { const int w = va_arg(va, int); if(w < 0) { flags |= FLAGS_LEFT; // reverse padding width = (unsigned int) - w; } else { width = (unsigned int)w; } format++; } // evaluate precision field precision = 0U; if(*format == '.') { flags |= FLAGS_PRECISION; format++; if(_is_digit(*format)) { precision = _atoi(&format); } else if(*format == '*') { const int prec = (int)va_arg(va, int); precision = prec > 0 ? (unsigned int)prec : 0U; format++; } } // evaluate length field switch(*format) { case 'l' : flags |= FLAGS_LONG; format++; if(*format == 'l') { flags |= FLAGS_LONG_LONG; format++; } break; case 'h' : flags |= FLAGS_SHORT; format++; if(*format == 'h') { flags |= FLAGS_CHAR; format++; } break; #if defined(PRINTF_SUPPORT_PTRDIFF_T) case 't' : flags |= (sizeof(ptrdiff_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG); format++; break; #endif case 'j' : flags |= (sizeof(intmax_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG); format++; break; case 'z' : flags |= (sizeof(size_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG); format++; break; default : break; } // evaluate specifier switch(*format) { case 'd' : case 'i' : case 'u' : case 'x' : case 'X' : case 'p' : case 'P' : case 'o' : case 'b' : { // set the base unsigned int base; if(*format == 'x' || *format == 'X') { base = 16U; } else if(*format == 'p' || *format == 'P') { base = 16U; flags |= FLAGS_HASH; // always hash for pointer format #if defined(PRINTF_SUPPORT_LONG_LONG) if(sizeof(uintptr_t) == sizeof(long long)) flags |= FLAGS_LONG_LONG; else #endif flags |= FLAGS_LONG; if(*(format + 1) == 'V') format++; } else if(*format == 'o') { base = 8U; } else if(*format == 'b') { base = 2U; } else { base = 10U; flags &= ~FLAGS_HASH; // no hash for dec format } // uppercase if(*format == 'X' || *format == 'P') { flags |= FLAGS_UPPERCASE; } // no plus or space flag for u, x, X, o, b if((*format != 'i') && (*format != 'd')) { flags &= ~(FLAGS_PLUS | FLAGS_SPACE); } // ignore '0' flag when precision is given if(flags & FLAGS_PRECISION) { flags &= ~FLAGS_ZEROPAD; } // convert the integer if((*format == 'i') || (*format == 'd')) { // signed if(flags & FLAGS_LONG_LONG) { #if defined(PRINTF_SUPPORT_LONG_LONG) const long long value = va_arg(va, long long); idx = _ntoa_long_long(out, buffer, idx, maxlen, (unsigned long long)(value > 0 ? value : 0 - value), value < 0, base, precision, width, flags); #endif } else if(flags & FLAGS_LONG) { const long value = va_arg(va, long); idx = _ntoa_long(out, buffer, idx, maxlen, (unsigned long)(value > 0 ? value : 0 - value), value < 0, base, precision, width, flags); } else { const int value = (flags & FLAGS_CHAR) ? (char)va_arg(va, int) : (flags & FLAGS_SHORT) ? (short int)va_arg(va, int) : va_arg(va, int); idx = _ntoa_long(out, buffer, idx, maxlen, (unsigned int)(value > 0 ? value : 0 - value), value < 0, base, precision, width, flags); } } else if(*format == 'V') { lv_vaformat_t * vaf = va_arg(va, lv_vaformat_t *); va_list copy; va_copy(copy, *vaf->va); idx += _vsnprintf(out, buffer + idx, maxlen - idx, vaf->fmt, copy); va_end(copy); } else { // unsigned if(flags & FLAGS_LONG_LONG) { #if defined(PRINTF_SUPPORT_LONG_LONG) idx = _ntoa_long_long(out, buffer, idx, maxlen, va_arg(va, unsigned long long), false, base, precision, width, flags); #endif } else if(flags & FLAGS_LONG) { idx = _ntoa_long(out, buffer, idx, maxlen, va_arg(va, unsigned long), false, base, precision, width, flags); } else { const unsigned int value = (flags & FLAGS_CHAR) ? (unsigned char)va_arg(va, unsigned int) : (flags & FLAGS_SHORT) ? (unsigned short int)va_arg(va, unsigned int) : va_arg(va, unsigned int); idx = _ntoa_long(out, buffer, idx, maxlen, value, false, base, precision, width, flags); } } format++; break; } #if defined(PRINTF_SUPPORT_FLOAT) case 'f' : case 'F' : if(*format == 'F') flags |= FLAGS_UPPERCASE; idx = _ftoa(out, buffer, idx, maxlen, va_arg(va, double), precision, width, flags); format++; break; #if defined(PRINTF_SUPPORT_EXPONENTIAL) case 'e': case 'E': case 'g': case 'G': if((*format == 'g') || (*format == 'G')) flags |= FLAGS_ADAPT_EXP; if((*format == 'E') || (*format == 'G')) flags |= FLAGS_UPPERCASE; idx = _etoa(out, buffer, idx, maxlen, va_arg(va, double), precision, width, flags); format++; break; #endif // PRINTF_SUPPORT_EXPONENTIAL #endif // PRINTF_SUPPORT_FLOAT case 'c' : { unsigned int l = 1U; // pre padding if(!(flags & FLAGS_LEFT)) { while(l++ < width) { out(' ', buffer, idx++, maxlen); } } // char output out((char)va_arg(va, int), buffer, idx++, maxlen); // post padding if(flags & FLAGS_LEFT) { while(l++ < width) { out(' ', buffer, idx++, maxlen); } } format++; break; } case 's' : { const char * p = va_arg(va, char *); unsigned int l = _strnlen_s(p, precision ? precision : (size_t) -1); // pre padding if(flags & FLAGS_PRECISION) { l = (l < precision ? l : precision); } if(!(flags & FLAGS_LEFT)) { while(l++ < width) { out(' ', buffer, idx++, maxlen); } } // string output while((*p != 0) && (!(flags & FLAGS_PRECISION) || precision--)) { out(*(p++), buffer, idx++, maxlen); } // post padding if(flags & FLAGS_LEFT) { while(l++ < width) { out(' ', buffer, idx++, maxlen); } } format++; break; } case '%' : out('%', buffer, idx++, maxlen); format++; break; default : out(*format, buffer, idx++, maxlen); format++; break; } } // termination out((char)0, buffer, idx < maxlen ? idx : maxlen - 1U, maxlen); // return written chars without terminating \0 return (int)idx; } /////////////////////////////////////////////////////////////////////////////// int lv_snprintf(char * buffer, size_t count, const char * format, ...) { va_list va; va_start(va, format); const int ret = _vsnprintf(_out_buffer, buffer, count, format, va); va_end(va); return ret; } int lv_vsnprintf(char * buffer, size_t count, const char * format, va_list va) { return _vsnprintf(_out_buffer, buffer, count, format, va); } #endif /*LV_SPRINTF_CUSTOM*/