/* vasprintf and asprintf with out-of-memory checking. Copyright (C) 1999, 2002-2004, 2006, 2007 Free Software Foundation, Inc. This program 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 program 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 this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include /* Specification. */ #include "xvasprintf.h" #include #include #include #include #include "xalloc.h" /* Checked size_t computations. */ #include "xsize.h" /* Some systems, like OSF/1 4.0 and Woe32, don't have EOVERFLOW. */ #ifndef EOVERFLOW # define EOVERFLOW E2BIG #endif static inline char * xstrcat (size_t argcount, va_list args) { char *result; va_list ap; size_t totalsize; size_t i; char *p; /* Determine the total size. */ totalsize = 0; va_copy (ap, args); for (i = argcount; i > 0; i--) { const char *next = va_arg (ap, const char *); totalsize = xsum (totalsize, strlen (next)); } va_end (ap); /* Test for overflow in the summing pass above or in (totalsize + 1) below. Also, don't return a string longer than INT_MAX, for consistency with vasprintf(). */ if (totalsize == SIZE_MAX || totalsize > INT_MAX) { errno = EOVERFLOW; return NULL; } /* Allocate and fill the result string. */ result = XNMALLOC (totalsize + 1, char); p = result; for (i = argcount; i > 0; i--) { const char *next = va_arg (args, const char *); size_t len = strlen (next); memcpy (p, next, len); p += len; } *p = '\0'; return result; } char * xvasprintf (const char *format, va_list args) { char *result; /* Recognize the special case format = "%s...%s". It is a frequently used idiom for string concatenation and needs to be fast. We don't want to have a separate function xstrcat() for this purpose. */ { size_t argcount = 0; const char *f; for (f = format;;) { if (*f == '\0') /* Recognized the special case of string concatenation. */ return xstrcat (argcount, args); if (*f != '%') break; f++; if (*f != 's') break; f++; argcount++; } } if (vasprintf (&result, format, args) < 0) { if (errno == ENOMEM) xalloc_die (); return NULL; } return result; }