/* * Copyright (C) 2000,2001,2003,2004 Manuel Novoa III <mjn3@codepoet.org> * * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. * * Dedicated to Toni. See uClibc/DEDICATION.mjn3 for details. */ #include "_stdio.h" #include <printf.h> #include <float.h> #include <locale.h> #include "_fpmaxtostr.h" /* * Function: * * ssize_t _fpmaxtostr(FILE * fp, __fpmax_t x, struct printf_info *info, * __fp_outfunc_t fp_outfunc); * * This is derived from the old _dtostr, whic I wrote for uClibc to provide * floating point support for the printf functions. It handles +/- infinity, * nan, and signed 0 assuming you have ieee arithmetic. It also now handles * digit grouping (for the uClibc supported locales) and hexadecimal float * notation. Finally, via the fp_outfunc parameter, it now supports wide * output. * * Notes: * * At most DECIMAL_DIG significant digits are kept. Any trailing digits * are treated as 0 as they are really just the results of rounding noise * anyway. If you want to do better, use an arbitary precision arithmetic * package. ;-) * * It should also be fairly portable, as no assumptions are made about the * bit-layout of doubles. Of course, that does make it less efficient than * it could be. */ /*****************************************************************************/ /* Don't change anything that follows unless you know what you're doing. */ /*****************************************************************************/ /* Fairly portable nan check. Bitwise for i386 generated larger code. * If you have a better version, comment this out. */ #define isnan(x) ((x) != (x)) /*****************************************************************************/ /* Don't change anything that follows peroid!!! ;-) */ /*****************************************************************************/ #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ #if FLT_RADIX != 2 #error FLT_RADIX != 2 is not currently supported #endif #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ #define NUM_HEX_DIGITS ((FPMAX_MANT_DIG + 3)/ 4) #define HEX_DIGITS_PER_BLOCK 8 /* Maximum number of subcases to output double is... * 0 - sign * 1 - padding and initial digit * 2 - digits left of the radix * 3 - 0s left of the radix or radix * 4 - radix or digits right of the radix * 5 - 0s right of the radix * 6 - exponent * 7 - trailing space padding * although not all cases may occur. */ #define MAX_CALLS 8 /*****************************************************************************/ #define NUM_HEX_DIGIT_BLOCKS \ ((NUM_HEX_DIGITS+HEX_DIGITS_PER_BLOCK-1)/HEX_DIGITS_PER_BLOCK) /*****************************************************************************/ static const char fmt[] = "inf\0INF\0nan\0NAN\0.\0,"; #define INF_OFFSET 0 /* must be 1st */ #define NAN_OFFSET 8 /* must be 2nd.. see hex sign handling */ #define DECPT_OFFSET 16 #define THOUSEP_OFFSET 18 #define EMPTY_STRING_OFFSET 3 /*****************************************************************************/ #if FPMAX_MAX_10_EXP < -FPMAX_MIN_10_EXP #error scaling code can not handle FPMAX_MAX_10_EXP < -FPMAX_MIN_10_EXP #endif static const __fpmax_t exp10_table[] = { 1e1L, 1e2L, 1e4L, 1e8L, 1e16L, 1e32L, /* floats */ #if FPMAX_MAX_10_EXP < 32 #error unsupported FPMAX_MAX_10_EXP (< 32). ANSI/ISO C requires >= 37. #endif #if FPMAX_MAX_10_EXP >= 64 1e64L, #endif #if FPMAX_MAX_10_EXP >= 128 1e128L, #endif #if FPMAX_MAX_10_EXP >= 256 1e256L, #endif #if FPMAX_MAX_10_EXP >= 512 1e512L, #endif #if FPMAX_MAX_10_EXP >= 1024 1e1024L, #endif #if FPMAX_MAX_10_EXP >= 2048 1e2048L, #endif #if FPMAX_MAX_10_EXP >= 4096 1e4096L #endif #if FPMAX_MAX_10_EXP >= 8192 #error unsupported FPMAX_MAX_10_EXP. please increase table #endif }; #define EXP10_TABLE_SIZE (sizeof(exp10_table)/sizeof(exp10_table[0])) #define EXP10_TABLE_MAX (1U<<(EXP10_TABLE_SIZE-1)) /*****************************************************************************/ #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ #if FLT_RADIX != 2 #error FLT_RADIX != 2 is not currently supported #endif #if FPMAX_MAX_EXP < -FPMAX_MIN_EXP #error scaling code can not handle FPMAX_MAX_EXP < -FPMAX_MIN_EXP #endif static const __fpmax_t exp16_table[] = { 0x1.0p4L, 0x1.0p8L, 0x1.0p16L, 0x1.0p32L, 0x1.0p64L, #if FPMAX_MAX_EXP >= 128 0x1.0p128L, #endif #if FPMAX_MAX_EXP >= 256 0x1.0p256L, #endif #if FPMAX_MAX_EXP >= 512 0x1.0p512L, #endif #if FPMAX_MAX_EXP >= 1024 0x1.0p1024L, #endif #if FPMAX_MAX_EXP >= 2048 0x1.0p2048L, #endif #if FPMAX_MAX_EXP >= 4096 0x1.0p4096L, #endif #if FPMAX_MAX_EXP >= 8192 0x1.0p8192L, #endif #if FPMAX_MAX_EXP >= 16384 0x1.0p16384L #endif #if FPMAX_MAX_EXP >= 32768 #error unsupported FPMAX_MAX_EXP. please increase table #endif }; #define EXP16_TABLE_SIZE (sizeof(exp16_table)/sizeof(exp16_table[0])) #define EXP16_TABLE_MAX (1U<<(EXP16_TABLE_SIZE-1)) #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ /*****************************************************************************/ #define FPO_ZERO_PAD (0x80 | '0') #define FPO_STR_WIDTH (0x80 | ' '); #define FPO_STR_PREC 'p' ssize_t _fpmaxtostr(FILE * fp, __fpmax_t x, struct printf_info *info, __fp_outfunc_t fp_outfunc) { #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ __fpmax_t lower_bnd; __fpmax_t upper_bnd = 1e9; #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ uint_fast32_t base = 10; const __fpmax_t *power_table; int dpb = DIGITS_PER_BLOCK; int ndb = NUM_DIGIT_BLOCKS; int nd = DECIMAL_DIG; int sufficient_precision = 0; #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ #ifdef __UCLIBC_HAS_GLIBC_DIGIT_GROUPING__ int num_groups = 0; int initial_group; /* This does not need to be initialized. */ int tslen; /* This does not need to be initialized. */ int nblk2; /* This does not need to be initialized. */ const char *ts; /* This does not need to be initialized. */ #endif /* __UCLIBC_HAS_GLIBC_DIGIT_GROUPING__ */ int round, o_exp; int exp; int width, preci; int cnt; char *s; char *e; intptr_t pc_fwi[3*MAX_CALLS]; intptr_t *ppc; intptr_t *ppc_last; char exp_buf[16]; char buf[BUF_SIZE]; char sign_str[6]; /* Last 2 are for 1st digit + nul. */ char o_mode; char mode; width = info->width; preci = info->prec; mode = info->spec; *exp_buf = 'e'; if ((mode|0x20) == 'a') { #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ *exp_buf = 'p'; if (preci < 0) { preci = NUM_HEX_DIGITS; sufficient_precision = 1; } #else mode += ('g' - 'a'); #endif } if (preci < 0) { preci = 6; } *sign_str = '\0'; if (PRINT_INFO_FLAG_VAL(info,showsign)) { *sign_str = '+'; } else if (PRINT_INFO_FLAG_VAL(info,space)) { *sign_str = ' '; } *(sign_str+1) = 0; pc_fwi[5] = INF_OFFSET; if (isnan(x)) { /* First, check for nan. */ pc_fwi[5] = NAN_OFFSET; goto INF_NAN; } if (x == 0) { /* Handle 0 now to avoid false positive. */ #ifdef __UCLIBC_HAVE_SIGNED_ZERO__ union { double x; struct { unsigned int l1, l2; } i; } u = {x}; if (u.i.l1 ^ u.i.l2) { /* Handle 'signed' zero. */ *sign_str = '-'; } #endif /* __UCLIBC_HAVE_SIGNED_ZERO__ */ exp = -1; goto GENERATE_DIGITS; } if (x < 0) { /* Convert negatives to positives. */ *sign_str = '-'; x = -x; } if (__FPMAX_ZERO_OR_INF_CHECK(x)) { /* Inf since zero handled above. */ INF_NAN: info->pad = ' '; ppc = pc_fwi + 6; pc_fwi[3] = FPO_STR_PREC; pc_fwi[4] = 3; if (mode < 'a') { pc_fwi[5] += 4; } pc_fwi[5] = (intptr_t)(fmt + pc_fwi[5]); goto EXIT_SPECIAL; } { int i, j; #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ if ((mode|0x20) == 'a') { lower_bnd = 0x1.0p31L; upper_bnd = 0x1.0p32L; power_table = exp16_table; exp = HEX_DIGITS_PER_BLOCK - 1; i = EXP16_TABLE_SIZE; j = EXP16_TABLE_MAX; dpb = HEX_DIGITS_PER_BLOCK; ndb = NUM_HEX_DIGIT_BLOCKS; nd = NUM_HEX_DIGITS; base = 16; } else { lower_bnd = 1e8; /* upper_bnd = 1e9; */ power_table = exp10_table; exp = DIGITS_PER_BLOCK - 1; i = EXP10_TABLE_SIZE; j = EXP10_TABLE_MAX; /* dpb = DIGITS_PER_BLOCK; */ /* ndb = NUM_DIGIT_BLOCKS; */ /* base = 10; */ } #else /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ #define lower_bnd 1e8 #define upper_bnd 1e9 #define power_table exp10_table #define dpb DIGITS_PER_BLOCK #define base 10 #define ndb NUM_DIGIT_BLOCKS #define nd DECIMAL_DIG exp = DIGITS_PER_BLOCK - 1; i = EXP10_TABLE_SIZE; j = EXP10_TABLE_MAX; #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ { int exp_neg = 0; if (x < lower_bnd) { /* Do we need to scale up or down? */ exp_neg = 1; } do { --i; if (exp_neg) { if (x * power_table[i] < upper_bnd) { x *= power_table[i]; exp -= j; } } else { if (x / power_table[i] >= lower_bnd) { x /= power_table[i]; exp += j; } } j >>= 1; } while (i); } } if (x >= upper_bnd) { /* Handle bad rounding case. */ x /= power_table[0]; ++exp; } assert(x < upper_bnd); GENERATE_DIGITS: { int i, j; s = buf + 2; /* Leave space for '\0' and '0'. */ i = 0; do { uint_fast32_t digit_block = (uint_fast32_t) x; assert(digit_block < upper_bnd); x = (x - digit_block) * upper_bnd; s += dpb; j = 0; do { s[- ++j] = '0' + (digit_block % base); digit_block /= base; } while (j < dpb); } while (++i < ndb); } /*************************************************************************/ if (mode < 'a') { *exp_buf -= ('a' - 'A'); /* e->E and p->P */ mode += ('a' - 'A'); } o_mode = mode; if ((mode == 'g') && (preci > 0)){ --preci; } round = preci; if (mode == 'f') { round += exp; if (round < -1) { memset(buf, '0', DECIMAL_DIG); /* OK, since 'f' -> decimal case. */ exp = -1; round = -1; } } s = buf; *s++ = 0; /* Terminator for rounding and 0-triming. */ *s = '0'; /* Space to round. */ { int i; i = 0; e = s + nd + 1; if (round < nd) { e = s + round + 2; if (*e >= '0' + (base/2)) { /* NOTE: We always round away from 0! */ i = 1; } } do { /* Handle rounding and trim trailing 0s. */ *--e += i; /* Add the carry. */ } while ((*e == '0') || (*e > '0' - 1 + base)); } #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ if ((mode|0x20) == 'a') { char *q; for (q = e ; *q ; --q) { if (*q > '9') { *q += (*exp_buf - ('p' - 'a') - '9' - 1); } } if (e > s) { exp *= 4; /* Change from base 16 to base 2. */ } } #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ o_exp = exp; if (e <= s) { /* We carried into an extra digit. */ ++o_exp; e = s; /* Needed if all 0s. */ } else { ++s; } *++e = 0; /* Terminating nul char. */ if ((mode == 'g') && ((o_exp >= -4) && (o_exp <= round))) { mode = 'f'; preci = round - o_exp; } exp = o_exp; if (mode != 'f') { o_exp = 0; } if (o_exp < 0) { /* Exponent is < 0, so */ *--s = '0'; /* fake the first 0 digit. */ } pc_fwi[3] = FPO_ZERO_PAD; pc_fwi[4] = 1; pc_fwi[5] = (intptr_t)(sign_str + 4); sign_str[4] = *s++; sign_str[5] = 0; ppc = pc_fwi + 6; { int i = e - s; /* Total digits is 'i'. */ if (o_exp >= 0) { #ifdef __UCLIBC_HAS_GLIBC_DIGIT_GROUPING__ const char *p; if (PRINT_INFO_FLAG_VAL(info,group) && *(p = __UCLIBC_CURLOCALE->grouping) ) { int nblk1; nblk2 = nblk1 = *p; if (*++p) { nblk2 = *p; assert(!*++p); } if (o_exp >= nblk1) { num_groups = (o_exp - nblk1) / nblk2 + 1; initial_group = (o_exp - nblk1) % nblk2; #ifdef __UCLIBC_HAS_WCHAR__ if (PRINT_INFO_FLAG_VAL(info,wide)) { /* _fp_out_wide() will fix this up. */ ts = fmt + THOUSEP_OFFSET; tslen = 1; } else { #endif /* __UCLIBC_HAS_WCHAR__ */ ts = __UCLIBC_CURLOCALE->thousands_sep; tslen = __UCLIBC_CURLOCALE->thousands_sep_len; #ifdef __UCLIBC_HAS_WCHAR__ } #endif /* __UCLIBC_HAS_WCHAR__ */ width -= num_groups * tslen; } } #endif /* __UCLIBC_HAS_GLIBC_DIGIT_GROUPING__ */ ppc[0] = FPO_STR_PREC; ppc[2] = (intptr_t)(s); if (o_exp >= i) { /* all digit(s) left of decimal */ ppc[1] = i; ppc += 3; o_exp -= i; i = 0; if (o_exp>0) { /* have 0s left of decimal */ ppc[0] = FPO_ZERO_PAD; ppc[1] = o_exp; ppc[2] = (intptr_t)(fmt + EMPTY_STRING_OFFSET); ppc += 3; } } else if (o_exp > 0) { /* decimal between digits */ ppc[1] = o_exp; ppc += 3; s += o_exp; i -= o_exp; } o_exp = -1; } if (PRINT_INFO_FLAG_VAL(info,alt) || (i) || ((o_mode != 'g') #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ && (o_mode != 'a') #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ && (preci > 0)) ) { ppc[0] = FPO_STR_PREC; #ifdef __LOCALE_C_ONLY ppc[1] = 1; ppc[2] = (intptr_t)(fmt + DECPT_OFFSET); #else /* __LOCALE_C_ONLY */ #ifdef __UCLIBC_HAS_WCHAR__ if (PRINT_INFO_FLAG_VAL(info,wide)) { /* _fp_out_wide() will fix this up. */ ppc[1] = 1; ppc[2] = (intptr_t)(fmt + DECPT_OFFSET); } else { #endif /* __UCLIBC_HAS_WCHAR__ */ ppc[1] = __UCLIBC_CURLOCALE->decimal_point_len; ppc[2] = (intptr_t)(__UCLIBC_CURLOCALE->decimal_point); #ifdef __UCLIBC_HAS_WCHAR__ } #endif /* __UCLIBC_HAS_WCHAR__ */ #endif /* __LOCALE_C_ONLY */ ppc += 3; } if (++o_exp < 0) { /* Have 0s right of decimal. */ ppc[0] = FPO_ZERO_PAD; ppc[1] = -o_exp; ppc[2] = (intptr_t)(fmt + EMPTY_STRING_OFFSET); ppc += 3; } if (i) { /* Have digit(s) right of decimal. */ ppc[0] = FPO_STR_PREC; ppc[1] = i; ppc[2] = (intptr_t)(s); ppc += 3; } if (((o_mode != 'g') || PRINT_INFO_FLAG_VAL(info,alt)) #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ && !sufficient_precision #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ ) { i -= o_exp; if (i < preci) { /* Have 0s right of digits. */ i = preci - i; ppc[0] = FPO_ZERO_PAD; ppc[1] = i; ppc[2] = (intptr_t)(fmt + EMPTY_STRING_OFFSET); ppc += 3; } } } /* Build exponent string. */ if (mode != 'f') { char *p = exp_buf + sizeof(exp_buf); int j; char exp_char = *exp_buf; char exp_sign = '+'; #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ int min_exp_dig_plus_2 = ((o_mode != 'a') ? (2+2) : (2+1)); #else /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ #define min_exp_dig_plus_2 (2+2) #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ if (exp < 0) { exp_sign = '-'; exp = -exp; } *--p = 0; /* nul-terminate */ j = 2; /* Count exp_char and exp_sign. */ do { *--p = '0' + (exp % 10); exp /= 10; } while ((++j < min_exp_dig_plus_2) || exp); /* char+sign+mindigits */ *--p = exp_sign; *--p = exp_char; ppc[0] = FPO_STR_PREC; ppc[1] = j; ppc[2] = (intptr_t)(p); ppc += 3; } EXIT_SPECIAL: { int i; ppc_last = ppc; ppc = pc_fwi + 4; /* Need width fields starting with second. */ do { width -= *ppc; ppc += 3; } while (ppc < ppc_last); ppc = pc_fwi; ppc[0] = FPO_STR_WIDTH; ppc[1] = i = ((*sign_str) != 0); ppc[2] = (intptr_t) sign_str; #ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__ if (((mode|0x20) == 'a') && (pc_fwi[3] >= 16)) { /* Hex sign handling. */ /* Hex and not inf or nan, so prefix with 0x. */ char *h = sign_str + i; *h = '0'; *++h = 'x' - 'p' + *exp_buf; *++h = 0; ppc[1] = (i += 2); } #endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */ if ((width -= i) > 0) { if (PRINT_INFO_FLAG_VAL(info,left)) { /* Left-justified. */ ppc_last[0] = FPO_STR_WIDTH; ppc_last[1] = width; ppc_last[2] = (intptr_t)(fmt + EMPTY_STRING_OFFSET); ppc_last += 3; } else if (info->pad == '0') { /* 0 padding */ ppc[4] += width; /* Pad second field. */ } else { ppc[1] += width; /* Pad first (sign) field. */ } } cnt = 0; } do { #ifdef __UCLIBC_HAS_GLIBC_DIGIT_GROUPING__ if ((ppc == pc_fwi + 6) && num_groups) { const char *gp = (const char *) ppc[2]; int len = ppc[1]; int blk = initial_group; cnt += num_groups * tslen; /* Adjust count now for sep chars. */ /* __printf("\n"); */ do { if (!blk) { /* Initial group could be 0 digits long! */ blk = nblk2; } else if (len >= blk) { /* Enough digits for a group. */ /* __printf("norm: len=%d blk=%d \"%.*s\"\n", len, blk, blk, gp); */ if (fp_outfunc(fp, *ppc, blk, (intptr_t) gp) != blk) { return -1; } assert(gp); if (*gp) { gp += blk; } len -= blk; } else { /* Transition to 0s. */ /* __printf("trans: len=%d blk=%d \"%.*s\"\n", len, blk, len, gp); */ if (len) { /* __printf("len\n"); */ if (fp_outfunc(fp, *ppc, len, (intptr_t) gp) != len) { return -1; } gp += len; } if (ppc[3] == FPO_ZERO_PAD) { /* Need to group 0s */ /* __printf("zeropad\n"); */ cnt += ppc[1]; ppc += 3; gp = (const char *) ppc[2]; blk -= len; /* blk > len, so blk still > 0. */ len = ppc[1]; continue; /* Don't decrement num_groups here. */ } else { assert(num_groups == 0); break; } } if (num_groups <= 0) { break; } --num_groups; if (fp_outfunc(fp, FPO_STR_PREC, tslen, (intptr_t) ts) != tslen) { return -1; } blk = nblk2; /* __printf("num_groups=%d blk=%d\n", num_groups, blk); */ } while (1); } else #endif /* __UCLIBC_HAS_GLIBC_DIGIT_GROUPING__ */ { /* NOTE: Remember 'else' above! */ if (fp_outfunc(fp, *ppc, ppc[1], ppc[2]) != ppc[1]) { return -1; } } cnt += ppc[1]; ppc += 3; } while (ppc < ppc_last); return cnt; }