📄 vasnprintf.c
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/* vsprintf with automatic memory allocation. Copyright (C) 1999, 2002-2005 Free Software Foundation, Inc. This program 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, 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 Library General Public License for more details. You should have received a copy of the GNU Library 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. *//* Tell glibc's <stdio.h> to provide a prototype for snprintf(). This must come before <config.h> because <config.h> may include <features.h>, and once <features.h> has been included, it's too late. */#ifndef _GNU_SOURCE# define _GNU_SOURCE 1#endif#ifdef HAVE_CONFIG_H# include <config.h>#endif#ifndef IN_LIBINTL# include <alloca.h>#endif/* Specification. */#if WIDE_CHAR_VERSION# include "vasnwprintf.h"#else# include "vasnprintf.h"#endif#include <stdio.h> /* snprintf(), sprintf() */#include <stdlib.h> /* abort(), malloc(), realloc(), free() */#include <string.h> /* memcpy(), strlen() */#include <errno.h> /* errno */#include <limits.h> /* CHAR_BIT, INT_MAX */#include <float.h> /* DBL_MAX_EXP, LDBL_MAX_EXP */#if WIDE_CHAR_VERSION# include "wprintf-parse.h"#else# include "printf-parse.h"#endif/* 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#ifdef HAVE_WCHAR_T# ifdef HAVE_WCSLEN# define local_wcslen wcslen# else /* Solaris 2.5.1 has wcslen() in a separate library libw.so. To avoid a dependency towards this library, here is a local substitute. Define this substitute only once, even if this file is included twice in the same compilation unit. */# ifndef local_wcslen_defined# define local_wcslen_defined 1static size_tlocal_wcslen (const wchar_t *s){ const wchar_t *ptr; for (ptr = s; *ptr != (wchar_t) 0; ptr++) ; return ptr - s;}# endif# endif#endif#if WIDE_CHAR_VERSION# define VASNPRINTF vasnwprintf# define CHAR_T wchar_t# define DIRECTIVE wchar_t_directive# define DIRECTIVES wchar_t_directives# define PRINTF_PARSE wprintf_parse# define USE_SNPRINTF 1# if HAVE_DECL__SNWPRINTF /* On Windows, the function swprintf() has a different signature than on Unix; we use the _snwprintf() function instead. */# define SNPRINTF _snwprintf# else /* Unix. */# define SNPRINTF swprintf# endif#else# define VASNPRINTF vasnprintf# define CHAR_T char# define DIRECTIVE char_directive# define DIRECTIVES char_directives# define PRINTF_PARSE printf_parse# define USE_SNPRINTF (HAVE_DECL__SNPRINTF || HAVE_SNPRINTF)# if HAVE_DECL__SNPRINTF /* Windows. */# define SNPRINTF _snprintf# else /* Unix. */# define SNPRINTF snprintf# endif#endifCHAR_T *VASNPRINTF (CHAR_T *resultbuf, size_t *lengthp, const CHAR_T *format, va_list args){ DIRECTIVES d; arguments a; if (PRINTF_PARSE (format, &d, &a) < 0) { errno = EINVAL; return NULL; }#define CLEANUP() \ free (d.dir); \ if (a.arg) \ free (a.arg); if (printf_fetchargs (args, &a) < 0) { CLEANUP (); errno = EINVAL; return NULL; } { size_t buf_neededlength; CHAR_T *buf; CHAR_T *buf_malloced; const CHAR_T *cp; size_t i; DIRECTIVE *dp; /* Output string accumulator. */ CHAR_T *result; size_t allocated; size_t length; /* Allocate a small buffer that will hold a directive passed to sprintf or snprintf. */ buf_neededlength = xsum4 (7, d.max_width_length, d.max_precision_length, 6);#if HAVE_ALLOCA if (buf_neededlength < 4000 / sizeof (CHAR_T)) { buf = (CHAR_T *) alloca (buf_neededlength * sizeof (CHAR_T)); buf_malloced = NULL; } else#endif { size_t buf_memsize = xtimes (buf_neededlength, sizeof (CHAR_T)); if (size_overflow_p (buf_memsize)) goto out_of_memory_1; buf = (CHAR_T *) malloc (buf_memsize); if (buf == NULL) goto out_of_memory_1; buf_malloced = buf; } if (resultbuf != NULL) { result = resultbuf; allocated = *lengthp; } else { result = NULL; allocated = 0; } length = 0; /* Invariants: result is either == resultbuf or == NULL or malloc-allocated. If length > 0, then result != NULL. */ /* Ensures that allocated >= needed. Aborts through a jump to out_of_memory if needed is SIZE_MAX or otherwise too big. */#define ENSURE_ALLOCATION(needed) \ if ((needed) > allocated) \ { \ size_t memory_size; \ CHAR_T *memory; \ \ allocated = (allocated > 0 ? xtimes (allocated, 2) : 12); \ if ((needed) > allocated) \ allocated = (needed); \ memory_size = xtimes (allocated, sizeof (CHAR_T)); \ if (size_overflow_p (memory_size)) \ goto out_of_memory; \ if (result == resultbuf || result == NULL) \ memory = (CHAR_T *) malloc (memory_size); \ else \ memory = (CHAR_T *) realloc (result, memory_size); \ if (memory == NULL) \ goto out_of_memory; \ if (result == resultbuf && length > 0) \ memcpy (memory, result, length * sizeof (CHAR_T)); \ result = memory; \ } for (cp = format, i = 0, dp = &d.dir[0]; ; cp = dp->dir_end, i++, dp++) { if (cp != dp->dir_start) { size_t n = dp->dir_start - cp; size_t augmented_length = xsum (length, n); ENSURE_ALLOCATION (augmented_length); memcpy (result + length, cp, n * sizeof (CHAR_T)); length = augmented_length; } if (i == d.count) break; /* Execute a single directive. */ if (dp->conversion == '%') { size_t augmented_length; if (!(dp->arg_index == ARG_NONE)) abort (); augmented_length = xsum (length, 1); ENSURE_ALLOCATION (augmented_length); result[length] = '%'; length = augmented_length; } else { if (!(dp->arg_index != ARG_NONE)) abort (); if (dp->conversion == 'n') { switch (a.arg[dp->arg_index].type) { case TYPE_COUNT_SCHAR_POINTER: *a.arg[dp->arg_index].a.a_count_schar_pointer = length; break; case TYPE_COUNT_SHORT_POINTER: *a.arg[dp->arg_index].a.a_count_short_pointer = length; break; case TYPE_COUNT_INT_POINTER: *a.arg[dp->arg_index].a.a_count_int_pointer = length; break; case TYPE_COUNT_LONGINT_POINTER: *a.arg[dp->arg_index].a.a_count_longint_pointer = length; break;#ifdef HAVE_LONG_LONG case TYPE_COUNT_LONGLONGINT_POINTER: *a.arg[dp->arg_index].a.a_count_longlongint_pointer = length; break;#endif default: abort (); } } else { arg_type type = a.arg[dp->arg_index].type; CHAR_T *p; unsigned int prefix_count; int prefixes[2];#if !USE_SNPRINTF size_t tmp_length; CHAR_T tmpbuf[700]; CHAR_T *tmp; /* Allocate a temporary buffer of sufficient size for calling sprintf. */ { size_t width; size_t precision; width = 0; if (dp->width_start != dp->width_end) { if (dp->width_arg_index != ARG_NONE) { int arg; if (!(a.arg[dp->width_arg_index].type == TYPE_INT)) abort (); arg = a.arg[dp->width_arg_index].a.a_int; width = (arg < 0 ? (unsigned int) (-arg) : arg); } else { const CHAR_T *digitp = dp->width_start; do width = xsum (xtimes (width, 10), *digitp++ - '0'); while (digitp != dp->width_end); } } precision = 6; if (dp->precision_start != dp->precision_end) { if (dp->precision_arg_index != ARG_NONE) { int arg; if (!(a.arg[dp->precision_arg_index].type == TYPE_INT)) abort (); arg = a.arg[dp->precision_arg_index].a.a_int; precision = (arg < 0 ? 0 : arg); } else { const CHAR_T *digitp = dp->precision_start + 1; precision = 0; while (digitp != dp->precision_end) precision = xsum (xtimes (precision, 10), *digitp++ - '0'); } } switch (dp->conversion) { case 'd': case 'i': case 'u':# ifdef HAVE_LONG_LONG if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT) tmp_length = (unsigned int) (sizeof (unsigned long long) * CHAR_BIT * 0.30103 /* binary -> decimal */ * 2 /* estimate for FLAG_GROUP */ ) + 1 /* turn floor into ceil */ + 1; /* account for leading sign */ else# endif if (type == TYPE_LONGINT || type == TYPE_ULONGINT) tmp_length = (unsigned int) (sizeof (unsigned long) * CHAR_BIT * 0.30103 /* binary -> decimal */ * 2 /* estimate for FLAG_GROUP */ ) + 1 /* turn floor into ceil */ + 1; /* account for leading sign */ else tmp_length = (unsigned int) (sizeof (unsigned int) * CHAR_BIT * 0.30103 /* binary -> decimal */ * 2 /* estimate for FLAG_GROUP */ ) + 1 /* turn floor into ceil */ + 1; /* account for leading sign */ break; case 'o':# ifdef HAVE_LONG_LONG if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT) tmp_length = (unsigned int) (sizeof (unsigned long long) * CHAR_BIT * 0.333334 /* binary -> octal */ ) + 1 /* turn floor into ceil */ + 1; /* account for leading sign */ else# endif if (type == TYPE_LONGINT || type == TYPE_ULONGINT) tmp_length = (unsigned int) (sizeof (unsigned long) * CHAR_BIT * 0.333334 /* binary -> octal */ ) + 1 /* turn floor into ceil */ + 1; /* account for leading sign */ else tmp_length = (unsigned int) (sizeof (unsigned int) * CHAR_BIT * 0.333334 /* binary -> octal */ ) + 1 /* turn floor into ceil */ + 1; /* account for leading sign */ break; case 'x': case 'X':# ifdef HAVE_LONG_LONG if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT) tmp_length = (unsigned int) (sizeof (unsigned long long) * CHAR_BIT * 0.25 /* binary -> hexadecimal */ ) + 1 /* turn floor into ceil */ + 2; /* account for leading sign or alternate form */ else# endif if (type == TYPE_LONGINT || type == TYPE_ULONGINT) tmp_length = (unsigned int) (sizeof (unsigned long) * CHAR_BIT * 0.25 /* binary -> hexadecimal */ ) + 1 /* turn floor into ceil */ + 2; /* account for leading sign or alternate form */ else tmp_length = (unsigned int) (sizeof (unsigned int) * CHAR_BIT * 0.25 /* binary -> hexadecimal */ ) + 1 /* turn floor into ceil */ + 2; /* account for leading sign or alternate form */ break; case 'f': case 'F':# ifdef HAVE_LONG_DOUBLE if (type == TYPE_LONGDOUBLE) tmp_length = (unsigned int) (LDBL_MAX_EXP * 0.30103 /* binary -> decimal */ * 2 /* estimate for FLAG_GROUP */ ) + 1 /* turn floor into ceil */ + 10; /* sign, decimal point etc. */ else# endif tmp_length = (unsigned int) (DBL_MAX_EXP * 0.30103 /* binary -> decimal */ * 2 /* estimate for FLAG_GROUP */ ) + 1 /* turn floor into ceil */ + 10; /* sign, decimal point etc. */ tmp_length = xsum (tmp_length, precision); break; case 'e': case 'E': case 'g': case 'G': case 'a': case 'A': tmp_length = 12; /* sign, decimal point, exponent etc. */ tmp_length = xsum (tmp_length, precision); break; case 'c':# if defined HAVE_WINT_T && !WIDE_CHAR_VERSION if (type == TYPE_WIDE_CHAR) tmp_length = MB_CUR_MAX; else# endif tmp_length = 1; break;
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