my_vsnprintf.c
上传用户:tsgydb
上传日期:2007-04-14
资源大小:10674k
文件大小:3k
- /* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
-
- This library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public
- License as published by the Free Software Foundation; either
- version 2 of the License, or (at your option) any later version.
-
- This library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Library General Public License for more details.
-
- You should have received a copy of the GNU Library General Public
- License along with this library; if not, write to the Free
- Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- MA 02111-1307, USA */
- #include "mysys_priv.h"
- #include "mysys_err.h"
- #include <m_string.h>
- #include <stdarg.h>
- #include <m_ctype.h>
- int my_snprintf(char* to, size_t n, const char* fmt, ...)
- {
- va_list args;
- va_start(args,fmt);
- return my_vsnprintf(to, n, fmt, args);
- }
- int my_vsnprintf(char *to, size_t n, const char* fmt, va_list ap)
- {
- char *start=to, *end=to+n-1;
- for (; *fmt ; fmt++)
- {
- if (fmt[0] != '%')
- {
- if (to == end) /* End of buffer */
- break;
- *to++= *fmt; /* Copy ordinary char */
- continue;
- }
- /* Skipp if max size is used (to be compatible with printf) */
- fmt++;
- while (isdigit(*fmt) || *fmt == '.' || *fmt == '-')
- fmt++;
- if (*fmt == 'l')
- fmt++;
- if (*fmt == 's') /* String parameter */
- {
- reg2 char *par = va_arg(ap, char *);
- uint plen;
- if (!par) par = (char*)"(null)";
- plen = (uint) strlen(par);
- if ((uint) (end-to) > plen) /* Replace if possible */
- {
- to=strmov(to,par);
- continue;
- }
- }
- else if (*fmt == 'd' || *fmt == 'u') /* Integer parameter */
- {
- register int iarg;
- if ((uint) (end-to) < 16)
- break;
- iarg = va_arg(ap, int);
- if (*fmt == 'd')
- to=int10_to_str((long) iarg,to, -10);
- else
- to=int10_to_str((long) (uint) iarg,to,10);
- continue;
- }
- /* We come here on '%%', unknown code or too long parameter */
- if (to == end)
- break;
- *to++='%'; /* % used as % or unknown code */
- }
- *to=' '; /* End of errmessage */
- return (uint) (to - start);
- }
- #ifdef MAIN
- static void my_printf(const char * fmt, ...)
- {
- char buf[32];
- int n;
- va_list ar;
- va_start(ar, fmt);
- n = my_vsnprintf(buf, sizeof(buf),fmt, ar);
- printf(buf);
- printf("n=%d, strlen=%dn", n, strlen(buf));
- va_end(ar);
- }
- int main()
- {
-
- my_printf("Hellon");
- my_printf("Hello int, %dn", 1);
- my_printf("Hello string '%s'n", "I am a string");
- my_printf("Hello hack hack hack hack hack hack hack %dn", 1);
- my_printf("Hello %d hack %dn", 1, 4);
- my_printf("Hello %d hack hack hack hack hack %dn", 1, 4);
- my_printf("Hello '%s' hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhn", "hack");
- my_printf("Hello hhhhhhhhhhhhhh %d sssssssssssssssn", 1);
- my_printf("Hello %un", 1);
- my_printf("conn %ld to: '%-.64s' user: '%-.32s' host:
- `%-.64s' (%-.64s)", 1, 0,0,0,0);
- return 0;
- }
- #endif