ref: 6af132daa2d80608eeb817b461235af278f6aea8
dir: /libmp/mpfmt.c/
#include "os.h" #include <mp.h> #include <libsec.h> #include "dat.h" static int to64(mpint *b, char *buf, int len) { uchar *p; int n, rv; p = nil; n = mptobe(b, nil, 0, &p); if(n < 0) return -1; rv = enc64(buf, len, p, n); free(p); return rv; } static int to32(mpint *b, char *buf, int len) { uchar *p; int n, rv; // leave room for a multiple of 5 buffer size n = b->top*Dbytes + 5; p = malloc(n); if(p == nil) return -1; n = mptobe(b, p, n, nil); if(n < 0) return -1; // round up buffer size, enc32 only accepts a multiple of 5 if(n%5) n += 5 - (n%5); rv = enc32(buf, len, p, n); free(p); return rv; } static char set16[] = "0123456789ABCDEF"; static int to16(mpint *b, char *buf, int len) { mpdigit *p, x; int i, j; char *out, *eout; if(len < 1) return -1; out = buf; eout = buf+len; for(p = &b->p[b->top-1]; p >= b->p; p--){ x = *p; for(i = Dbits-4; i >= 0; i -= 4){ j = 0xf & (x>>i); if(j != 0 || out != buf){ if(out >= eout) return -1; *out++ = set16[j]; } } } if(out == buf) *out++ = '0'; if(out >= eout) return -1; *out = 0; return 0; } static char* modbillion(int rem, ulong r, char *out, char *buf) { ulong rr; int i; for(i = 0; i < 9; i++){ rr = r%10; r /= 10; if(out <= buf) return nil; *--out = '0' + rr; if(rem == 0 && r == 0) break; } return out; } static int to10(mpint *b, char *buf, int len) { mpint *d, *r, *billion; char *out; if(len < 1) return -1; d = mpcopy(b); r = mpnew(0); billion = uitomp(1000000000, nil); out = buf+len; *--out = 0; do { mpdiv(d, billion, d, r); out = modbillion(d->top, r->p[0], out, buf); if(out == nil) break; } while(d->top != 0); mpfree(d); mpfree(r); mpfree(billion); if(out == nil) return -1; len -= out-buf; if(out != buf) memmove(buf, out, len); return 0; } int mpfmt(Fmt *fmt) { mpint *b; char *p; b = va_arg(fmt->args, mpint*); if(b == nil) return fmtstrcpy(fmt, "*"); p = mptoa(b, fmt->prec, nil, 0); fmt->flags &= ~FmtPrec; if(p == nil) return fmtstrcpy(fmt, "*"); else{ fmtstrcpy(fmt, p); free(p); return 0; } } char* mptoa(mpint *b, int base, char *buf, int len) { char *out; int rv, alloced; alloced = 0; if(buf == nil){ len = ((b->top+1)*Dbits+2)/3 + 1; buf = malloc(len); if(buf == nil) return nil; alloced = 1; } if(len < 2) return nil; out = buf; if(b->sign < 0){ *out++ = '-'; len--; } switch(base){ case 64: rv = to64(b, out, len); break; case 32: rv = to32(b, out, len); break; default: case 16: rv = to16(b, out, len); break; case 10: rv = to10(b, out, len); break; } if(rv < 0){ if(alloced) free(buf); return nil; } return buf; }