contrib/libarchive/libarchive/archive_string_sprintf.c

   1 /*-
   2  * Copyright (c) 2003-2007 Tim Kientzle
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "archive_platform.h"
  27 __FBSDID("$FreeBSD: src/lib/libarchive/archive_string_sprintf.c,v 1.10 2008/03/14 22:00:09 kientzle Exp $");
  28
  29 /*
  30  * The use of printf()-family functions can be troublesome
  31  * for space-constrained applications.  In addition, correctly
  32  * implementing this function in terms of vsnprintf() requires
  33  * two calls (one to determine the size, another to format the
  34  * result), which in turn requires duplicating the argument list
  35  * using va_copy, which isn't yet universally available. <sigh>
  36  *
  37  * So, I've implemented a bare minimum of printf()-like capability
  38  * here.  This is only used to format error messages, so doesn't
  39  * require any floating-point support or field-width handling.
  40  */
  41
  42 #include <stdio.h>
  43
  44 #include "archive_string.h"
  45 #include "archive_private.h"
  46
  47 /*
  48  * Utility functions to format signed/unsigned integers and append
  49  * them to an archive_string.
  50  */
  51 static void
  52 append_uint(struct archive_string *as, uintmax_t d, unsigned base)
  53 {
  54         static const char *digits = "0123456789abcdef";
  55         if (d >= base)
  56                 append_uint(as, d/base, base);
  57         archive_strappend_char(as, digits[d % base]);
  58 }
  59
  60 static void
  61 append_int(struct archive_string *as, intmax_t d, unsigned base)
  62 {
  63         if (d < 0) {
  64                 archive_strappend_char(as, '-');
  65                 d = -d;
  66         }
  67         append_uint(as, d, base);
  68 }
  69
  70
  71 void
  72 __archive_string_sprintf(struct archive_string *as, const char *fmt, ...)
  73 {
  74         va_list ap;
  75
  76         va_start(ap, fmt);
  77         archive_string_vsprintf(as, fmt, ap);
  78         va_end(ap);
  79 }
  80
  81 /*
  82  * Like 'vsprintf', but ensures the target is big enough, resizing if
  83  * necessary.
  84  */
  85 void
  86 __archive_string_vsprintf(struct archive_string *as, const char *fmt,
  87     va_list ap)
  88 {
  89         char long_flag;
  90         intmax_t s; /* Signed integer temp. */
  91         uintmax_t u; /* Unsigned integer temp. */
  92         const char *p, *p2;
  93
  94         if (__archive_string_ensure(as, 64) == NULL)
  95                 __archive_errx(1, "Out of memory");
  96
  97         if (fmt == NULL) {
  98                 as->s[0] = 0;
  99                 return;
 100         }
 101
 102         for (p = fmt; *p != '\0'; p++) {
 103                 const char *saved_p = p;
 104
 105                 if (*p != '%') {
 106                         archive_strappend_char(as, *p);
 107                         continue;
 108                 }
 109
 110                 p++;
 111
 112                 long_flag = '\0';
 113                 switch(*p) {
 114                 case 'j':
 115                         long_flag = 'j';
 116                         p++;
 117                         break;
 118                 case 'l':
 119                         long_flag = 'l';
 120                         p++;
 121                         break;
 122                 }
 123
 124                 switch (*p) {
 125                 case '%':
 126                         __archive_strappend_char(as, '%');
 127                         break;
 128                 case 'c':
 129                         s = va_arg(ap, int);
 130                         __archive_strappend_char(as, s);
 131                         break;
 132                 case 'd':
 133                         switch(long_flag) {
 134                         case 'j': s = va_arg(ap, intmax_t); break;
 135                         case 'l': s = va_arg(ap, long); break;
 136                         default:  s = va_arg(ap, int); break;
 137                         }
 138                         append_int(as, s, 10);
 139                         break;
 140                 case 's':
 141                         p2 = va_arg(ap, char *);
 142                         archive_strcat(as, p2);
 143                         break;
 144                 case 'o': case 'u': case 'x': case 'X':
 145                         /* Common handling for unsigned integer formats. */
 146                         switch(long_flag) {
 147                         case 'j': u = va_arg(ap, uintmax_t); break;
 148                         case 'l': u = va_arg(ap, unsigned long); break;
 149                         default:  u = va_arg(ap, unsigned int); break;
 150                         }
 151                         /* Format it in the correct base. */
 152                         switch (*p) {
 153                         case 'o': append_uint(as, u, 8); break;
 154                         case 'u': append_uint(as, u, 10); break;
 155                         default: append_uint(as, u, 16); break;
 156                         }
 157                         break;
 158                 default:
 159                         /* Rewind and print the initial '%' literally. */
 160                         p = saved_p;
 161                         archive_strappend_char(as, *p);
 162                 }
 163         }
 164 }