diff options
author | redpony <redpony@ec762483-ff6d-05da-a07a-a48fb63a330f> | 2010-08-11 02:37:10 +0000 |
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committer | redpony <redpony@ec762483-ff6d-05da-a07a-a48fb63a330f> | 2010-08-11 02:37:10 +0000 |
commit | 80686d4e567bae579ea39e009826a2de92cd4ace (patch) | |
tree | c3c35fcba57dde423a248f38aa121ad197c79734 /utils/static_utoa.h | |
parent | 3c85c407c333899f6b4bc26632d312b8e568b638 (diff) |
major refactor, break bad circular deps
git-svn-id: https://ws10smt.googlecode.com/svn/trunk@509 ec762483-ff6d-05da-a07a-a48fb63a330f
Diffstat (limited to 'utils/static_utoa.h')
-rwxr-xr-x | utils/static_utoa.h | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/utils/static_utoa.h b/utils/static_utoa.h new file mode 100755 index 00000000..fe5f6d92 --- /dev/null +++ b/utils/static_utoa.h @@ -0,0 +1,115 @@ +#ifndef STATIC_UTOA_H +#define STATIC_UTOA_H + +#include "threadlocal.h" + + +#include <string> +#include <cstring> + +#define DIGIT_LOOKUP_TABLE 0 + +namespace { +THREADLOCAL char utoa_buf[] = "01234567890123456789"; // to put end of string character at buf[20] +const unsigned utoa_bufsize=sizeof(utoa_buf); +const unsigned utoa_bufsizem1=utoa_bufsize-1; +#ifdef DIGIT_LOOKUP_TABLE +char digits[] = "0123456789"; +#endif +} + +inline char digit_to_char(int d) { + return +#ifdef DIGIT_LOOKUP_TABLE + digits[d]; +#else + '0'+d; +#endif +} + +// returns n in string [return,num); *num=0 yourself before calling if you want a c_str +inline char *utoa(char *num,unsigned n) { + if ( !n ) { + *--num='0'; + } else { + unsigned rem; + // 3digit lookup table, divide by 1000 faster? + while ( n ) { +#if 1 + rem = n; + n /= 10; + rem -= 10*n; // maybe this is faster than mod because we are already dividing +#else + rem = n%10; // would optimizer combine these together? + n = n/10; +#endif + *--num = digit_to_char(rem); + } + } + return num; +} + +inline char *static_utoa(unsigned n) { + return utoa(utoa_buf+utoa_bufsizem1,n); +} + +//returns position of '\0' terminating number written starting at to +inline char* append_utoa(char *to,unsigned n) { + char *s=static_utoa(n); + int ns=(utoa_buf+utoa_bufsize)-s; + std::memcpy(to,s,ns); + return to+ns; +} + +// so named to avoid gcc segfault when named itoa +inline char *itoa(char *p,int n) { + if (n<0) { + p=utoa(p,-n); // TODO: check that (unsigned)(-INT_MIN) == 0x1000000 in 2s complement and not == 0 + *--p='-'; + return p; + } else + return utoa(p,n); +} + +inline char *static_itoa(int n) { + return itoa(utoa_buf+utoa_bufsizem1,n); +} + + +inline std::string utos(unsigned n) { + const int bufsz=20; + char buf[bufsz]; + char *end=buf+bufsz; + char *p=utoa(end,n); + return std::string(p,end); +} + +inline std::string itos(int n) { + const int bufsz=20; + char buf[bufsz]; + char *end=buf+bufsz; + char *p=itoa(end,n); + return std::string(p,end); +} + +#ifdef ITOA_SAMPLE +# include <cstdio> +# include <sstream> +# include <iostream> +using namespace std; + +int main(int argc,char *argv[]) { + printf("d U d U d U\n"); + for (int i=1;i<argc;++i) { + int n; + unsigned un; + sscanf(argv[i],"%d",&n); + sscanf(argv[i],"%u",&un); + printf("%d %u %s",n,un,static_itoa(n)); + printf(" %s %s %s\n",static_utoa(un),itos(n).c_str(),utos(un).c_str()); + } + return 0; +} +#endif + +#endif |