From 4b2249ae20cef82414e7e469c4ea51bd627daab1 Mon Sep 17 00:00:00 2001 From: ericb Date: Mon, 14 May 2007 19:42:47 +0000 Subject: [PATCH] Reduce stack size of *printf. * libc/stdio/vfprintf.c (_VFPRINTF_R): Fix use of decimal point in %f. Avoid malloc when possible for %S. (BUF): Improve stack locality by using smaller size. (MAXEXPLEN, _PRINTF_FLOAT_TYPE): Define. (exponent): Use smaller stack size. --- newlib/ChangeLog | 9 +++ newlib/libc/stdio/vfprintf.c | 187 +++++++++++++++++++------------------------ 2 files changed, 93 insertions(+), 103 deletions(-) diff --git a/newlib/ChangeLog b/newlib/ChangeLog index 6986e6e305..d41cba3a3f 100644 --- a/newlib/ChangeLog +++ b/newlib/ChangeLog @@ -1,3 +1,12 @@ +2007-05-14 Eric Blake + + Reduce stack size of *printf. + * libc/stdio/vfprintf.c (_VFPRINTF_R): Fix use of decimal point + in %f. Avoid malloc when possible for %S. + (BUF): Improve stack locality by using smaller size. + (MAXEXPLEN, _PRINTF_FLOAT_TYPE): Define. + (exponent): Use smaller stack size. + 2007-05-11 Eric Blake Minimize printf/scanf size on platforms that don't need C99. diff --git a/newlib/libc/stdio/vfprintf.c b/newlib/libc/stdio/vfprintf.c index 6175f0e096..5305840bbb 100644 --- a/newlib/libc/stdio/vfprintf.c +++ b/newlib/libc/stdio/vfprintf.c @@ -224,43 +224,66 @@ _DEFUN(__sbprintf, (rptr, fp, fmt, ap), #ifdef FLOATING_POINT -#include -#include -#include "floatio.h" - -#if ((MAXEXP+MAXFRACT+1) > MB_LEN_MAX) -# define BUF (MAXEXP+MAXFRACT+1) /* + decimal point */ -#else -# define BUF MB_LEN_MAX -#endif +# include +# include -#define DEFPREC 6 +/* For %La, an exponent of 15 bits occupies the exponent character, a + sign, and up to 5 digits. */ +# define MAXEXPLEN 7 +# define DEFPREC 6 + +# ifdef _NO_LONGDBL + +extern char *_dtoa_r _PARAMS((struct _reent *, double, int, + int, int *, int *, char **)); + +# define _PRINTF_FLOAT_TYPE double +# define _DTOA_R _dtoa_r +# define FREXP frexp + +# else /* !_NO_LONGDBL */ + +extern char *_ldtoa_r _PARAMS((struct _reent *, _LONG_DOUBLE, int, + int, int *, int *, char **)); -#ifdef _NO_LONGDBL -static char * -_EXFUN(cvt, (struct _reent *, double, int, int, char *, int *, int, int *, - char *)); -#else -static char * -_EXFUN(cvt, (struct _reent *, _LONG_DOUBLE, int, int, char *, int *, int, - int *, char *)); extern int _EXFUN(_ldcheck,(_LONG_DOUBLE *)); -#endif -static int _EXFUN(exponent, (char *, int, int)); +# define _PRINTF_FLOAT_TYPE _LONG_DOUBLE +# define _DTOA_R _ldtoa_r +/* FIXME - frexpl is not yet supported; and cvt infloops if (double)f + converts a finite value into infinity. */ +/* # define FREXP frexpl */ +# define FREXP(f,e) ((_LONG_DOUBLE) frexp ((double)f, e)) +# endif /* !_NO_LONGDBL */ -#else /* no FLOATING_POINT */ +static char *cvt(struct _reent *, _PRINTF_FLOAT_TYPE, int, int, char *, int *, + int, int *, char *); -#define BUF 40 +static int exponent(char *, int, int); #endif /* FLOATING_POINT */ +/* BUF must be big enough for the maximum %#llo (assuming long long is + at most 64 bits, this would be 23 characters), the maximum + multibyte character %C, and the maximum default precision of %La + (assuming long double is at most 128 bits with 113 bits of + mantissa, this would be 29 characters). %e, %f, and %g use + reentrant storage shared with mprec. All other formats that use + buf get by with fewer characters. Making BUF slightly bigger + reduces the need for malloc in %.*a and %S, when large precision or + long strings are processed. */ +#define BUF 40 +#if defined _MB_CAPABLE && MB_LEN_MAX > BUF +# undef BUF +# define BUF MB_LEN_MAX +#endif + #ifndef _NO_LONGLONG -#define quad_t long long -#define u_quad_t unsigned long long +# define quad_t long long +# define u_quad_t unsigned long long #else -#define quad_t long -#define u_quad_t unsigned long +# define quad_t long +# define u_quad_t unsigned long #endif typedef quad_t * quad_ptr_t; @@ -378,19 +401,13 @@ _DEFUN(_VFPRINTF_R, (data, fp, fmt0, ap), #ifdef FLOATING_POINT char *decimal_point = _localeconv_r (data)->decimal_point; char softsign; /* temporary negative sign for floats */ -# ifdef _NO_LONGDBL - union { int i; double d; } _double_ = {0}; -# define _fpvalue (_double_.d) -# else - union { int i; _LONG_DOUBLE ld; } _long_double_ = {0}; -# define _fpvalue (_long_double_.ld) - int tmp; -# endif + union { int i; _PRINTF_FLOAT_TYPE fp; } _double_ = {0}; +# define _fpvalue (_double_.fp) int expt; /* integer value of exponent */ int expsize = 0; /* character count for expstr */ int ndig = 0; /* actual number of digits returned by cvt */ - char expstr[7]; /* buffer for exponent string */ -#endif + char expstr[MAXEXPLEN]; /* buffer for exponent string */ +#endif /* FLOATING_POINT */ u_quad_t _uquad; /* integer arguments %[diouxX] */ enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */ int dprec; /* a copy of prec if [diouxX], 0 otherwise */ @@ -400,7 +417,7 @@ _DEFUN(_VFPRINTF_R, (data, fp, fmt0, ap), #define NIOV 8 struct __suio uio; /* output information: summary */ struct __siov iov[NIOV];/* ... and individual io vectors */ - char buf[BUF]; /* space for %c, %[diouxX], %[eEfgG] */ + char buf[BUF]; /* space for %c, %S, %[diouxX], %[aA] */ char ox[2]; /* space for 0x hex-prefix */ #ifdef _MB_CAPABLE wchar_t wc; @@ -875,8 +892,8 @@ reswitch: switch (ch) { } /* do this before tricky precision changes */ - tmp = _ldcheck (&_fpvalue); - if (tmp == 2) { + expt = _ldcheck (&_fpvalue); + if (expt == 2) { if (_fpvalue < 0) sign = '-'; if (ch <= 'G') /* 'A', 'E', 'F', or 'G' */ @@ -887,7 +904,7 @@ reswitch: switch (ch) { flags &= ~ZEROPAD; break; } - if (tmp == 1) { + if (expt == 1) { if (ch <= 'G') /* 'A', 'E', 'F', or 'G' */ cp = "NAN"; else @@ -1030,8 +1047,8 @@ reswitch: switch (ch) { while (1) { if (wcp[m] == L'\0') break; - if ((n = (int)_wcrtomb_r (data, - buf, wcp[m], &ps)) == -1) { + if ((n = (int)_wcrtomb_r (data, + buf, wcp[m], &ps)) == -1) { fp->_flags |= __SERR; goto error; } @@ -1044,31 +1061,35 @@ reswitch: switch (ch) { } } else { - if ((size = (int)_wcsrtombs_r (data, - NULL, &wcp, 0, &ps)) == -1) { + if ((size = (int)_wcsrtombs_r (data, + NULL, &wcp, 0, &ps)) == -1) { fp->_flags |= __SERR; goto error; } wcp = (_CONST wchar_t *)cp; } - + if (size == 0) break; - - if ((malloc_buf = - (char *)_malloc_r (data, size + 1)) == NULL) { - fp->_flags |= __SERR; - goto error; - } - + + if (size >= BUF) { + if ((malloc_buf = + (char *)_malloc_r (data, size + 1)) + == NULL) { + fp->_flags |= __SERR; + goto error; + } + cp = malloc_buf; + } else + cp = buf; + /* Convert widechar string to multibyte string. */ memset ((_PTR)&ps, '\0', sizeof (mbstate_t)); - if (_wcsrtombs_r (data, malloc_buf, - &wcp, size, &ps) != size) { + if (_wcsrtombs_r (data, malloc_buf, + &wcp, size, &ps) != size) { fp->_flags |= __SERR; goto error; } - cp = malloc_buf; cp[size] = '\0'; } #endif /* _MB_CAPABLE */ @@ -1254,11 +1275,11 @@ number: if ((dprec = prec) >= 0) PRINT (cp, ndig); PAD (expt - ndig, zeroes); if (flags & ALT) - PRINT (".", 1); + PRINT (decimal_point, 1); } else { PRINT (cp, expt); cp += expt; - PRINT (".", 1); + PRINT (decimal_point, 1); PRINT (cp, ndig - expt); } } else { /* 'a', 'A', 'e', or 'E' */ @@ -1305,21 +1326,6 @@ error: #ifdef FLOATING_POINT -# ifdef _NO_LONGDBL -extern char *_dtoa_r _PARAMS((struct _reent *, double, int, - int, int *, int *, char **)); -# define _DTOA_R _dtoa_r -# define FREXP frexp -# else -extern char *_ldtoa_r _PARAMS((struct _reent *, _LONG_DOUBLE, int, - int, int *, int *, char **)); -# define _DTOA_R _ldtoa_r -/* FIXME - frexpl is not yet supported; and cvt infloops if (double)f - converts a finite value into infinity. */ -/* # define FREXP frexpl */ -# define FREXP(f,e) ((_LONG_DOUBLE) frexp ((double)f, e)) -# endif - /* Using reentrant DATA, convert finite VALUE into a string of digits with no decimal point, using NDIGITS precision and FLAGS as guides to whether trailing zeros must be included. Set *SIGN to nonzero @@ -1327,31 +1333,9 @@ extern char *_ldtoa_r _PARAMS((struct _reent *, _LONG_DOUBLE, int, *LENGTH to the length of the returned string. CH must be one of [aAeEfFgG]; if it is [aA], then the return string lives in BUF, otherwise the return value shares the mprec reentrant storage. */ -# ifdef _NO_LONGDBL -static char * -_DEFUN(cvt, (data, value, ndigits, flags, sign, decpt, ch, length, buf), - struct _reent *data _AND - double value _AND - int ndigits _AND - int flags _AND - char *sign _AND - int *decpt _AND - int ch _AND - int *length _AND - char *buf) -# else static char * -_DEFUN(cvt, (data, value, ndigits, flags, sign, decpt, ch, length, buf), - struct _reent *data _AND - _LONG_DOUBLE value _AND - int ndigits _AND - int flags _AND - char *sign _AND - int *decpt _AND - int ch _AND - int *length _AND - char *buf) -# endif +cvt(struct _reent *data, _PRINTF_FLOAT_TYPE value, int ndigits, int flags, + char *sign, int *decpt, int ch, int *length, char *buf) { int mode, dsgn; char *digits, *bp, *rve; @@ -1444,13 +1428,10 @@ _DEFUN(cvt, (data, value, ndigits, flags, sign, decpt, ch, length, buf), } static int -_DEFUN(exponent, (p0, exp, fmtch), - char *p0 _AND - int exp _AND - int fmtch) +exponent(char *p0, int exp, int fmtch) { register char *p, *t; - char expbuf[10]; + char expbuf[MAXEXPLEN]; # ifdef _WANT_IO_C99_FORMATS int isa = fmtch == 'a' || fmtch == 'A'; # else @@ -1465,13 +1446,13 @@ _DEFUN(exponent, (p0, exp, fmtch), } else *p++ = '+'; - t = expbuf + 10; + t = expbuf + MAXEXPLEN; if (exp > 9) { do { *--t = to_char (exp % 10); } while ((exp /= 10) > 9); *--t = to_char (exp); - for (; t < expbuf + 10; *p++ = *t++); + for (; t < expbuf + MAXEXPLEN; *p++ = *t++); } else { if (!isa) -- 2.11.0