FreeCalypso > hg > freecalypso-sw
diff gsm-fw/sprintf/vspcore.c @ 145:7e45ada9c365
gsm-fw: sprintf overhaul in preparation for adding %f format support
author | Michael Spacefalcon <msokolov@ivan.Harhan.ORG> |
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date | Thu, 14 Nov 2013 17:51:33 +0000 |
parents | |
children | 4d629b6bbcfd |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gsm-fw/sprintf/vspcore.c Thu Nov 14 17:51:33 2013 +0000 @@ -0,0 +1,287 @@ +/* + * Embedded [v]sprintf() implementation by Michael Spacefalcon, + * loosely based on the 4.3BSD-Tahoe version. + * + * This module contains the core of the vsprintf() function, which may + * be either used directly by user code or called by the sprintf() + * trivial wrapper. + */ + +#include <sys/types.h> +#include <ctype.h> +#include <stdarg.h> +#include "defs.h" + +extern u_char * _sprintf_integer(u_char *op, int width, int flags, int sign, + unsigned number, int base, int prec); +extern u_char * _sprintf_percent_f(u_char *op, int width, int flags, int sign, + double number, int prec); + +u_char * +_sprintf_field(u_char *op, int width, int flags, int sign, + u_char *body, int size, int dprec, int fpprec) +{ + int fieldsz; /* field size expanded by sign, etc */ + int realsz; /* field size expanded by decimal precision */ + int n; /* scratch */ + + /* + * All reasonable formats wind up here. At this point, + * `body' points to a string which (if not flags&LADJUST) + * should be padded out to `width' places. If + * flags&ZEROPAD, it should first be prefixed by any + * sign or other prefix; otherwise, it should be blank + * padded before the prefix is emitted. After any + * left-hand padding and prefixing, emit zeroes + * required by a decimal [diouxX] precision, then print + * the string proper, then emit zeroes required by any + * leftover floating precision; finally, if LADJUST, + * pad with blanks. + */ + + /* + * compute actual size, so we know how much to pad + * fieldsz excludes decimal prec; realsz includes it + */ + fieldsz = size + fpprec; + if (sign) + fieldsz++; + if (flags & HEXPREFIX) + fieldsz += 2; + realsz = dprec > fieldsz ? dprec : fieldsz; + + /* right-adjusting blank padding */ + if ((flags & (LADJUST|ZEROPAD)) == 0 && width) + for (n = realsz; n < width; n++) + *op++ = ' '; + /* prefix */ + if (sign) + *op++ = sign; + if (flags & HEXPREFIX) { + *op++ = '0'; + *op++ = (flags & UPPERCASE) ? 'X' : 'x'; + } + /* right-adjusting zero padding */ + if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) + for (n = realsz; n < width; n++) + *op++ = '0'; + /* leading zeroes from decimal precision */ + for (n = fieldsz; n < dprec; n++) + *op++ = '0'; + + /* the string or number proper */ + bcopy(body, op, size); + op += size; + /* trailing f.p. zeroes */ + while (--fpprec >= 0) + *op++ = '0'; + /* left-adjusting padding (always blank) */ + if (flags & LADJUST) + for (n = realsz; n < width; n++) + *op++ = ' '; + + return(op); +} + +int +vsprintf(buf0, fmt0, argp) + u_char *buf0, *fmt0; + va_list argp; +{ + u_char *op; /* output buffer working ptr */ + u_char *fmt; /* format string working ptr */ + int ch; /* character from fmt */ + int n; /* scratch integer */ + char *t; /* scratch pointer */ + int flags; /* flags as above */ + int prec; /* precision from format (%.3d), or -1 */ + int width; /* width from format (%8d), or 0 */ + char sign; /* sign prefix (' ', '+', '-', or \0) */ + unsigned un; /* unsigned number for conversion */ + + op = buf0; + for (fmt = fmt0; ; ++fmt) { + for (; (ch = *fmt) && ch != '%'; ++fmt) + *op++ = ch; + if (!ch) { +out: *op = '\0'; + return (op - buf0); + } + + flags = 0; width = 0; + prec = -1; + sign = '\0'; + +rflag: switch (*++fmt) { + case ' ': + /* + * ``If the space and + flags both appear, the space + * flag will be ignored.'' + * -- ANSI X3J11 + */ + if (!sign) + sign = ' '; + goto rflag; + case '#': + flags |= ALT; + goto rflag; + case '*': + /* + * ``A negative field width argument is taken as a + * - flag followed by a positive field width.'' + * -- ANSI X3J11 + * They don't exclude field widths read from args. + */ + if ((width = va_arg(argp, int)) >= 0) + goto rflag; + width = -width; + /* FALLTHROUGH */ + case '-': + flags |= LADJUST; + goto rflag; + case '+': + sign = '+'; + goto rflag; + case '.': + if (*++fmt == '*') + n = va_arg(argp, int); + else { + n = 0; + while (isascii(*fmt) && isdigit(*fmt)) + n = 10 * n + todigit(*fmt++); + --fmt; + } + prec = n < 0 ? -1 : n; + goto rflag; + case '0': + /* + * ``Note that 0 is taken as a flag, not as the + * beginning of a field width.'' + * -- ANSI X3J11 + */ + flags |= ZEROPAD; + goto rflag; + case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + n = 0; + do { + n = 10 * n + todigit(*fmt); + } while (isascii(*++fmt) && isdigit(*fmt)); + width = n; + --fmt; + goto rflag; + case 'L': + flags |= LONGDBL; + goto rflag; + case 'h': + flags |= SHORTINT; + goto rflag; + case 'l': + flags |= LONGINT; + goto rflag; + case 'c': + /* + * XXX reusing a variable of type char + * for an unrelated purpose + */ + sign = (char) va_arg(argp, int); + op = _sprintf_field(op, width, flags, 0, &sign, 1, + 0, 0); + break; + case 'D': + flags |= LONGINT; + /*FALLTHROUGH*/ + case 'd': + case 'i': + n = va_arg(argp, int); + if (n < 0) { + un = -n; + sign = '-'; + } else + un = n; + op = _sprintf_integer(op, width, flags, sign, un, 10, + prec); + break; +#if 0 // not yet implemented + case 'f': + op = _sprintf_percent_f(op, width, flags, sign, + va_arg(argp, double), prec); + break; +#endif + case 'n': + n = op - buf0; + if (flags & LONGINT) + *va_arg(argp, long *) = n; + else if (flags & SHORTINT) + *va_arg(argp, short *) = n; + else + *va_arg(argp, int *) = n; + break; + case 'O': + flags |= LONGINT; + /*FALLTHROUGH*/ + case 'o': + un = va_arg(argp, unsigned); + op = _sprintf_integer(op, width, flags, 0, un, 8, prec); + break; + case 'p': + /* + * ``The argument shall be a pointer to void. The + * value of the pointer is converted to a sequence + * of printable characters, in an implementation- + * defined manner.'' + * -- ANSI X3J11 + */ + /* NOSTRICT */ + un = (unsigned)va_arg(argp, void *); + op = _sprintf_integer(op, width, flags | HEXPREFIX, 0, + un, 16, prec); + break; + case 's': + if (!(t = va_arg(argp, char *))) + t = "(null)"; + if (prec >= 0) { + /* + * can't use strlen; can only look for the + * NUL in the first `prec' characters, and + * strlen() will go further. + */ + char *p, *memchr(); + + if (p = memchr(t, 0, prec)) { + n = p - t; + if (n > prec) + n = prec; + } else + n = prec; + } else + n = strlen(t); + op = _sprintf_field(op, width, flags, 0, t, n, 0, 0); + break; + case 'U': + flags |= LONGINT; + /*FALLTHROUGH*/ + case 'u': + un = va_arg(argp, unsigned); + op = _sprintf_integer(op, width, flags, 0, un, 10, + prec); + break; + case 'X': + flags |= UPPERCASE; + /* FALLTHROUGH */ + case 'x': + un = va_arg(argp, unsigned); + /* leading 0x/X only if non-zero */ + if (flags & ALT && un != 0) + flags |= HEXPREFIX; + op = _sprintf_integer(op, width, flags, 0, un, 16, + prec); + break; + case '\0': /* "%?" prints ?, unless ? is NULL */ + goto out; + default: + *op++ = *fmt; + } + } + /* NOTREACHED */ +}