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Diffstat (limited to 'strings/int2str.c')
| -rw-r--r-- | strings/int2str.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/strings/int2str.c b/strings/int2str.c new file mode 100644 index 00000000..9d099d2e --- /dev/null +++ b/strings/int2str.c @@ -0,0 +1,176 @@ +/* Copyright (c) 2000 TXT DataKonsult Ab & Monty Program Ab + Copyright (c) 2009-2011, Monty Program Ab + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + 2. Redistributions in binary form must the following disclaimer in + the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``AS IS'' AND ANY + EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR + CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND + ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + SUCH DAMAGE. +*/ + +#include "strings_def.h" + +/* + _dig_vec arrays are public because they are used in several outer places. +*/ +const char _dig_vec_upper[] = + "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; +const char _dig_vec_lower[] = + "0123456789abcdefghijklmnopqrstuvwxyz"; + + +/* + Convert integer to its string representation in given scale of notation. + + SYNOPSIS + int2str() + val - value to convert + dst - points to buffer where string representation should be stored + radix - radix of scale of notation + upcase - set to 1 if we should use upper-case digits + + DESCRIPTION + Converts the (long) integer value to its character form and moves it to + the destination buffer followed by a terminating NUL. + If radix is -2..-36, val is taken to be SIGNED, if radix is 2..36, val is + taken to be UNSIGNED. That is, val is signed if and only if radix is. + All other radixes treated as bad and nothing will be changed in this case. + + For conversion to decimal representation (radix is -10 or 10) one can use + optimized int10_to_str() function. + + RETURN VALUE + Pointer to ending NUL character or NullS if radix is bad. +*/ + +char * +int2str(register long int val, register char *dst, register int radix, + int upcase) +{ + char buffer[65]; + register char *p; + long int new_val; + const char *dig_vec= upcase ? _dig_vec_upper : _dig_vec_lower; + ulong uval= (ulong) val; + + if (radix < 0) + { + if (radix < -36 || radix > -2) + return NullS; + if (val < 0) + { + *dst++ = '-'; + /* Avoid integer overflow in (-val) for LONGLONG_MIN (BUG#31799). */ + uval = (ulong)0 - uval; + } + radix = -radix; + } + else if (radix > 36 || radix < 2) + return NullS; + + /* + The slightly contorted code which follows is due to the fact that + few machines directly support unsigned long / and %. Certainly + the VAX C compiler generates a subroutine call. In the interests + of efficiency (hollow laugh) I let this happen for the first digit + only; after that "val" will be in range so that signed integer + division will do. Sorry 'bout that. CHECK THE CODE PRODUCED BY + YOUR C COMPILER. The first % and / should be unsigned, the second + % and / signed, but C compilers tend to be extraordinarily + sensitive to minor details of style. This works on a VAX, that's + all I claim for it. + */ + p = &buffer[sizeof(buffer)-1]; + *p = '\0'; + new_val= uval / (ulong) radix; + *--p = dig_vec[(uchar) (uval- (ulong) new_val*(ulong) radix)]; + val = new_val; +#ifdef HAVE_LDIV + while (val != 0) + { + ldiv_t res; + res=ldiv(val,radix); + *--p = dig_vec[res.rem]; + val= res.quot; + } +#else + while (val != 0) + { + new_val=val/radix; + *--p = dig_vec[(uchar) (val-new_val*radix)]; + val= new_val; + } +#endif + while ((*dst++ = *p++) != 0) ; + return dst-1; +} + + +/* + Converts integer to its string representation in decimal notation. + + SYNOPSIS + int10_to_str() + val - value to convert + dst - points to buffer where string representation should be stored + radix - flag that shows whenever val should be taken as signed or not + + DESCRIPTION + This is version of int2str() function which is optimized for normal case + of radix 10/-10. It takes only sign of radix parameter into account and + not its absolute value. + + RETURN VALUE + Pointer to ending NUL character. +*/ + +char *int10_to_str(long int val,char *dst,int radix) +{ + char buffer[65]; + register char *p; + long int new_val; + unsigned long int uval = (unsigned long int) val; + + if (radix < 0) /* -10 */ + { + if (val < 0) + { + *dst++ = '-'; + /* Avoid integer overflow in (-val) for LONGLONG_MIN (BUG#31799). */ + uval = (unsigned long int)0 - uval; + } + } + + p = &buffer[sizeof(buffer)-1]; + *p = '\0'; + new_val= (long) (uval / 10); + *--p = '0'+ (char) (uval - (unsigned long) new_val * 10); + val = new_val; + + while (val != 0) + { + new_val=val/10; + *--p = '0' + (char) (val-new_val*10); + val= new_val; + } + while ((*dst++ = *p++) != 0) ; + return dst-1; +} |