X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=gmp%2Fprintf%2Fvasprintf.c;fp=gmp%2Fprintf%2Fvasprintf.c;h=4ed4c5dbe2809f3a5b765ebeb045e694ad3550f0;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/gmp/printf/vasprintf.c b/gmp/printf/vasprintf.c new file mode 100644 index 00000000..4ed4c5db --- /dev/null +++ b/gmp/printf/vasprintf.c @@ -0,0 +1,113 @@ +/* gmp_vasprintf -- formatted output to an allocated space. + +Copyright 2001 Free Software Foundation, Inc. + +This file is part of the GNU MP Library. + +The GNU MP Library is free software; you can redistribute it and/or modify +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 3 of the License, or (at your +option) any later version. + +The GNU MP 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 Lesser General Public +License for more details. + +You should have received a copy of the GNU Lesser General Public License +along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ + +#include "config.h" + +#if HAVE_STDARG +#include +#else +#include +#endif + +#include +#include +#include + +#include "gmp.h" +#include "gmp-impl.h" + +#if ! HAVE_VSNPRINTF +#define vsnprintf __gmp_replacement_vsnprintf +#endif + + +/* vasprintf isn't used since we prefer all GMP allocs to go through + __gmp_allocate_func, and in particular we don't want the -1 return from + vasprintf for out-of-memory, instead __gmp_allocate_func should handle + that. Using vsnprintf unfortunately means we might have to re-run it if + our current space is insufficient. + + The initial guess for the needed space is an arbitrary 256 bytes. If + that (and any extra GMP_ASPRINTF_T_NEED might give) isn't enough then an + ISO C99 standard vsnprintf will tell us what we really need. + + GLIBC 2.0.x vsnprintf returns either -1 or space-1 to indicate overflow, + without giving any indication how much is really needed. In this case + keep trying with double the space each time. + + A return of space-1 is success on a C99 vsnprintf, but we're not + bothering to identify which style vsnprintf we've got, so just take the + pessimistic option and assume it's glibc 2.0.x. + + Notice the use of ret+2 for the new space in the C99 case. This ensures + the next vsnprintf return value will be space-2, which is unambiguously + successful. But actually GMP_ASPRINTF_T_NEED() will realloc to even + bigger than that ret+2. + + vsnprintf might trash it's given ap, so copy it in case we need to use it + more than once. See comments with gmp_snprintf_format. */ + +static int +gmp_asprintf_format (struct gmp_asprintf_t *d, const char *fmt, + va_list orig_ap) +{ + int ret; + va_list ap; + size_t space = 256; + + for (;;) + { + GMP_ASPRINTF_T_NEED (d, space); + space = d->alloc - d->size; + va_copy (ap, orig_ap); + ret = vsnprintf (d->buf + d->size, space, fmt, ap); + if (ret == -1) + { + ASSERT (strlen (d->buf + d->size) == space-1); + ret = space-1; + } + + /* done if output fits in our space */ + if (ret < space-1) + break; + + if (ret == space-1) + space *= 2; /* possible glibc 2.0.x, so double */ + else + space = ret+2; /* C99, so now know space required */ + } + + d->size += ret; + return ret; +} + +const struct doprnt_funs_t __gmp_asprintf_funs = { + (doprnt_format_t) gmp_asprintf_format, + (doprnt_memory_t) __gmp_asprintf_memory, + (doprnt_reps_t) __gmp_asprintf_reps, + (doprnt_final_t) __gmp_asprintf_final +}; + +int +gmp_vasprintf (char **result, const char *fmt, va_list ap) +{ + struct gmp_asprintf_t d; + GMP_ASPRINTF_T_INIT (d, result); + return __gmp_doprnt (&__gmp_asprintf_funs, &d, fmt, ap); +}