| /* Implement the vsnprintf function. |
| Copyright (C) 2003-2019 Free Software Foundation, Inc. |
| Written by Kaveh R. Ghazi <ghazi@caip.rutgers.edu>. |
| |
| This file is part of the libiberty library. This library is free |
| software; you can redistribute it and/or modify it under the |
| terms of the GNU General Public License as published by the |
| Free Software Foundation; either version 2, 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 General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU CC; see the file COPYING. If not, write to |
| the Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. |
| |
| As a special exception, if you link this library with files |
| compiled with a GNU compiler to produce an executable, this does not cause |
| the resulting executable to be covered by the GNU General Public License. |
| This exception does not however invalidate any other reasons why |
| the executable file might be covered by the GNU General Public License. */ |
| |
| /* |
| |
| @deftypefn Supplemental int vsnprintf (char *@var{buf}, size_t @var{n}, @ |
| const char *@var{format}, va_list @var{ap}) |
| |
| This function is similar to @code{vsprintf}, but it will write to |
| @var{buf} at most @code{@var{n}-1} bytes of text, followed by a |
| terminating null byte, for a total of @var{n} bytes. On error the |
| return value is -1, otherwise it returns the number of characters that |
| would have been printed had @var{n} been sufficiently large, |
| regardless of the actual value of @var{n}. Note some pre-C99 system |
| libraries do not implement this correctly so users cannot generally |
| rely on the return value if the system version of this function is |
| used. |
| |
| @end deftypefn |
| |
| */ |
| |
| #include "config.h" |
| #include "ansidecl.h" |
| |
| #include <stdarg.h> |
| #ifdef HAVE_STRING_H |
| #include <string.h> |
| #endif |
| #ifdef HAVE_STDLIB_H |
| #include <stdlib.h> |
| #endif |
| |
| #include "libiberty.h" |
| |
| /* This implementation relies on a working vasprintf. */ |
| int |
| vsnprintf (char *s, size_t n, const char *format, va_list ap) |
| { |
| char *buf = 0; |
| int result = vasprintf (&buf, format, ap); |
| |
| if (!buf) |
| return -1; |
| if (result < 0) |
| { |
| free (buf); |
| return -1; |
| } |
| |
| result = strlen (buf); |
| if (n > 0) |
| { |
| if ((long) n > result) |
| memcpy (s, buf, result+1); |
| else |
| { |
| memcpy (s, buf, n-1); |
| s[n - 1] = 0; |
| } |
| } |
| free (buf); |
| return result; |
| } |
| |
| #ifdef TEST |
| /* Set the buffer to a known state. */ |
| #define CLEAR(BUF) do { memset ((BUF), 'X', sizeof (BUF)); (BUF)[14] = '\0'; } while (0) |
| /* For assertions. */ |
| #define VERIFY(P) do { if (!(P)) abort(); } while (0) |
| |
| static int ATTRIBUTE_PRINTF_3 |
| checkit (char *s, size_t n, const char *format, ...) |
| { |
| int result; |
| va_list ap; |
| va_start (ap, format); |
| result = vsnprintf (s, n, format, ap); |
| va_end (ap); |
| return result; |
| } |
| |
| extern int main (void); |
| int |
| main (void) |
| { |
| char buf[128]; |
| int status; |
| |
| CLEAR (buf); |
| status = checkit (buf, 10, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "foobar:9\0XXXXX\0", 15) == 0); |
| |
| CLEAR (buf); |
| status = checkit (buf, 9, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "foobar:9\0XXXXX\0", 15) == 0); |
| |
| CLEAR (buf); |
| status = checkit (buf, 8, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "foobar:\0XXXXXX\0", 15) == 0); |
| |
| CLEAR (buf); |
| status = checkit (buf, 7, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "foobar\0XXXXXXX\0", 15) == 0); |
| |
| CLEAR (buf); |
| status = checkit (buf, 6, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "fooba\0XXXXXXXX\0", 15) == 0); |
| |
| CLEAR (buf); |
| status = checkit (buf, 2, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "f\0XXXXXXXXXXXX\0", 15) == 0); |
| |
| CLEAR (buf); |
| status = checkit (buf, 1, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "\0XXXXXXXXXXXXX\0", 15) == 0); |
| |
| CLEAR (buf); |
| status = checkit (buf, 0, "%s:%d", "foobar", 9); |
| VERIFY (status==8 && memcmp (buf, "XXXXXXXXXXXXXX\0", 15) == 0); |
| |
| return 0; |
| } |
| #endif /* TEST */ |