xref: /openbsd-src/gnu/lib/libiberty/src/vasprintf.c (revision 8500990981f885cbe5e6a4958549cacc238b5ae6)
1 /* Like vsprintf but provides a pointer to malloc'd storage, which must
2    be freed by the caller.
3    Copyright (C) 1994 Free Software Foundation, Inc.
4 
5 This file is part of the libiberty library.
6 Libiberty is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public
8 License as published by the Free Software Foundation; either
9 version 2 of the License, or (at your option) any later version.
10 
11 Libiberty is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 Library General Public License for more details.
15 
16 You should have received a copy of the GNU Library General Public
17 License along with libiberty; see the file COPYING.LIB.  If
18 not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA.  */
20 
21 #ifdef HAVE_CONFIG_H
22 #include "config.h"
23 #endif
24 #include <ansidecl.h>
25 #ifdef ANSI_PROTOTYPES
26 #include <stdarg.h>
27 #else
28 #include <varargs.h>
29 #endif
30 #include <stdio.h>
31 #ifdef HAVE_STRING_H
32 #include <string.h>
33 #endif
34 #ifdef HAVE_STDLIB_H
35 #include <stdlib.h>
36 #else
37 extern unsigned long strtoul ();
38 extern PTR malloc ();
39 #endif
40 #include "libiberty.h"
41 
42 #ifdef TEST
43 int global_total_width;
44 #endif
45 
46 /*
47 
48 @deftypefn Extension int vasprintf (char **@var{resptr}, const char *@var{format}, va_list @var{args})
49 
50 Like @code{vsprintf}, but instead of passing a pointer to a buffer,
51 you pass a pointer to a pointer.  This function will compute the size
52 of the buffer needed, allocate memory with @code{malloc}, and store a
53 pointer to the allocated memory in @code{*@var{resptr}}.  The value
54 returned is the same as @code{vsprintf} would return.  If memory could
55 not be allocated, zero is returned and @code{NULL} is stored in
56 @code{*@var{resptr}}.
57 
58 @end deftypefn
59 
60 */
61 
62 static int int_vasprintf PARAMS ((char **, const char *, va_list *));
63 
64 static int
65 int_vasprintf (result, format, args)
66      char **result;
67      const char *format;
68      va_list *args;
69 {
70   const char *p = format;
71   /* Add one to make sure that it is never zero, which might cause malloc
72      to return NULL.  */
73   int total_width = strlen (format) + 1;
74   va_list ap;
75 
76   memcpy ((PTR) &ap, (PTR) args, sizeof (va_list));
77 
78   while (*p != '\0')
79     {
80       if (*p++ == '%')
81 	{
82 	  while (strchr ("-+ #0", *p))
83 	    ++p;
84 	  if (*p == '*')
85 	    {
86 	      ++p;
87 	      total_width += abs (va_arg (ap, int));
88 	    }
89 	  else
90 	    total_width += strtoul (p, (char **) &p, 10);
91 	  if (*p == '.')
92 	    {
93 	      ++p;
94 	      if (*p == '*')
95 		{
96 		  ++p;
97 		  total_width += abs (va_arg (ap, int));
98 		}
99 	      else
100 	      total_width += strtoul (p, (char **) &p, 10);
101 	    }
102 	  while (strchr ("hlL", *p))
103 	    ++p;
104 	  /* Should be big enough for any format specifier except %s and floats.  */
105 	  total_width += 30;
106 	  switch (*p)
107 	    {
108 	    case 'd':
109 	    case 'i':
110 	    case 'o':
111 	    case 'u':
112 	    case 'x':
113 	    case 'X':
114 	    case 'c':
115 	      (void) va_arg (ap, int);
116 	      break;
117 	    case 'f':
118 	    case 'e':
119 	    case 'E':
120 	    case 'g':
121 	    case 'G':
122 	      (void) va_arg (ap, double);
123 	      /* Since an ieee double can have an exponent of 307, we'll
124 		 make the buffer wide enough to cover the gross case. */
125 	      total_width += 307;
126 	      break;
127 	    case 's':
128 	      total_width += strlen (va_arg (ap, char *));
129 	      break;
130 	    case 'p':
131 	    case 'n':
132 	      (void) va_arg (ap, char *);
133 	      break;
134 	    }
135 	  p++;
136 	}
137     }
138 #ifdef TEST
139   global_total_width = total_width;
140 #endif
141   *result = (char *) malloc (total_width);
142   if (*result != NULL)
143     return vsprintf (*result, format, *args);
144   else
145     return 0;
146 }
147 
148 int
149 vasprintf (result, format, args)
150      char **result;
151      const char *format;
152 #if defined (_BSD_VA_LIST_) && defined (__FreeBSD__)
153      _BSD_VA_LIST_ args;
154 #else
155      va_list args;
156 #endif
157 {
158   return int_vasprintf (result, format, &args);
159 }
160 
161 #ifdef TEST
162 static void ATTRIBUTE_PRINTF_1
163 checkit VPARAMS ((const char *format, ...))
164 {
165   char *result;
166   VA_OPEN (args, format);
167   VA_FIXEDARG (args, const char *, format);
168   vasprintf (&result, format, args);
169   VA_CLOSE (args);
170 
171   if (strlen (result) < (size_t) global_total_width)
172     printf ("PASS: ");
173   else
174     printf ("FAIL: ");
175   printf ("%d %s\n", global_total_width, result);
176 
177   free (result);
178 }
179 
180 extern int main PARAMS ((void));
181 
182 int
183 main ()
184 {
185   checkit ("%d", 0x12345678);
186   checkit ("%200d", 5);
187   checkit ("%.300d", 6);
188   checkit ("%100.150d", 7);
189   checkit ("%s", "jjjjjjjjjiiiiiiiiiiiiiiioooooooooooooooooppppppppppppaa\n\
190 777777777777777777333333333333366666666666622222222222777777777777733333");
191   checkit ("%f%s%d%s", 1.0, "foo", 77, "asdjffffffffffffffiiiiiiiiiiixxxxx");
192 
193   return 0;
194 }
195 #endif /* TEST */
196