glib/gprintf.c

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997, 2002  Peter Mattis, Red Hat, Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include "config.h"
  21
  22 #include <stdarg.h>
  23 #include <stdlib.h>
  24 #include <stdio.h>
  25
  26 #include "gprintf.h"
  27 #include "gprintfint.h"
  28
  29
  30 /**
  31  * g_printf:
  32  * @format: a standard printf() format string, but notice
  33  *          <link linkend="string-precision">string precision pitfalls</link>.
  34  * @...: the arguments to insert in the output.
  35  *
  36  * An implementation of the standard printf() function which supports
  37  * positional parameters, as specified in the Single Unix Specification.
  38  *
  39  * Returns: the number of bytes printed.
  40  *
  41  * Since: 2.2
  42  **/
  43 gint
  44 g_printf (gchar const *format,
  45           ...)
  46 {
  47   va_list args;
  48   gint retval;
  49
  50   va_start (args, format);
  51   retval = g_vprintf (format, args);
  52   va_end (args);
  53
  54   return retval;
  55 }
  56
  57 /**
  58  * g_fprintf:
  59  * @file: the stream to write to.
  60  * @format: a standard printf() format string, but notice
  61  *          <link linkend="string-precision">string precision pitfalls</link>.
  62  * @...: the arguments to insert in the output.
  63  *
  64  * An implementation of the standard fprintf() function which supports
  65  * positional parameters, as specified in the Single Unix Specification.
  66  *
  67  * Returns: the number of bytes printed.
  68  *
  69  * Since: 2.2
  70  **/
  71 gint
  72 g_fprintf (FILE        *file,
  73            gchar const *format,
  74            ...)
  75 {
  76   va_list args;
  77   gint retval;
  78
  79   va_start (args, format);
  80   retval = g_vfprintf (file, format, args);
  81   va_end (args);
  82
  83   return retval;
  84 }
  85
  86 /**
  87  * g_sprintf:
  88  * @string: A pointer to a memory buffer to contain the resulting string. It
  89  *          is up to the caller to ensure that the allocated buffer is large
  90  *          enough to hold the formatted result
  91  * @format: a standard printf() format string, but notice
  92  *          <link linkend="string-precision">string precision pitfalls</link>.
  93  * @...: the arguments to insert in the output.
  94  *
  95  * An implementation of the standard sprintf() function which supports
  96  * positional parameters, as specified in the Single Unix Specification.
  97  *
  98  * Note that it is usually better to use g_snprintf(), to avoid the
  99  * risk of buffer overflow.
 100  *
 101  * See also g_strdup_printf().
 102  *
 103  * Returns: the number of bytes printed.
 104  *
 105  * Since: 2.2
 106  **/
 107 gint
 108 g_sprintf (gchar       *string,
 109            gchar const *format,
 110            ...)
 111 {
 112   va_list args;
 113   gint retval;
 114
 115   va_start (args, format);
 116   retval = g_vsprintf (string, format, args);
 117   va_end (args);
 118
 119   return retval;
 120 }
 121
 122 /**
 123  * g_snprintf:
 124  * @string: the buffer to hold the output.
 125  * @n: the maximum number of bytes to produce (including the
 126  *     terminating nul character).
 127  * @format: a standard printf() format string, but notice
 128  *          <link linkend="string-precision">string precision pitfalls</link>.
 129  * @...: the arguments to insert in the output.
 130  *
 131  * A safer form of the standard sprintf() function. The output is guaranteed
 132  * to not exceed @n characters (including the terminating nul character), so
 133  * it is easy to ensure that a buffer overflow cannot occur.
 134  *
 135  * See also g_strdup_printf().
 136  *
 137  * In versions of GLib prior to 1.2.3, this function may return -1 if the
 138  * output was truncated, and the truncated string may not be nul-terminated.
 139  * In versions prior to 1.3.12, this function returns the length of the output
 140  * string.
 141  *
 142  * The return value of g_snprintf() conforms to the snprintf()
 143  * function as standardized in ISO C99. Note that this is different from
 144  * traditional snprintf(), which returns the length of the output string.
 145  *
 146  * The format string may contain positional parameters, as specified in
 147  * the Single Unix Specification.
 148  *
 149  * Returns: the number of bytes which would be produced if the buffer
 150  *     was large enough.
 151  **/
 152 gint
 153 g_snprintf (gchar       *string,
 154             gulong       n,
 155             gchar const *format,
 156             ...)
 157 {
 158   va_list args;
 159   gint retval;
 160
 161   va_start (args, format);
 162   retval = g_vsnprintf (string, n, format, args);
 163   va_end (args);
 164
 165   return retval;
 166 }
 167
 168 /**
 169  * g_vprintf:
 170  * @format: a standard printf() format string, but notice
 171  *          <link linkend="string-precision">string precision pitfalls</link>.
 172  * @args: the list of arguments to insert in the output.
 173  *
 174  * An implementation of the standard vprintf() function which supports
 175  * positional parameters, as specified in the Single Unix Specification.
 176  *
 177  * Returns: the number of bytes printed.
 178  *
 179  * Since: 2.2
 180  **/
 181 gint
 182 g_vprintf (gchar const *format,
 183            va_list      args)
 184 {
 185   g_return_val_if_fail (format != NULL, -1);
 186
 187   return _g_vprintf (format, args);
 188 }
 189
 190 /**
 191  * g_vfprintf:
 192  * @file: the stream to write to.
 193  * @format: a standard printf() format string, but notice
 194  *          <link linkend="string-precision">string precision pitfalls</link>.
 195  * @args: the list of arguments to insert in the output.
 196  *
 197  * An implementation of the standard fprintf() function which supports
 198  * positional parameters, as specified in the Single Unix Specification.
 199  *
 200  * Returns: the number of bytes printed.
 201  *
 202  * Since: 2.2
 203  **/
 204 gint
 205 g_vfprintf (FILE        *file,
 206             gchar const *format,
 207             va_list      args)
 208 {
 209   g_return_val_if_fail (format != NULL, -1);
 210
 211   return _g_vfprintf (file, format, args);
 212 }
 213
 214 /**
 215  * g_vsprintf:
 216  * @string: the buffer to hold the output.
 217  * @format: a standard printf() format string, but notice
 218  *          <link linkend="string-precision">string precision pitfalls</link>.
 219  * @args: the list of arguments to insert in the output.
 220  *
 221  * An implementation of the standard vsprintf() function which supports
 222  * positional parameters, as specified in the Single Unix Specification.
 223  *
 224  * Returns: the number of bytes printed.
 225  *
 226  * Since: 2.2
 227  **/
 228 gint
 229 g_vsprintf (gchar        *string,
 230             gchar const *format,
 231             va_list      args)
 232 {
 233   g_return_val_if_fail (string != NULL, -1);
 234   g_return_val_if_fail (format != NULL, -1);
 235
 236   return _g_vsprintf (string, format, args);
 237 }
 238
 239 /**
 240  * g_vsnprintf:
 241  * @string: the buffer to hold the output.
 242  * @n: the maximum number of bytes to produce (including the
 243  *     terminating nul character).
 244  * @format: a standard printf() format string, but notice
 245  *          <link linkend="string-precision">string precision pitfalls</link>.
 246  * @args: the list of arguments to insert in the output.
 247  *
 248  * A safer form of the standard vsprintf() function. The output is guaranteed
 249  * to not exceed @n characters (including the terminating nul character), so
 250  * it is easy to ensure that a buffer overflow cannot occur.
 251  *
 252  * See also g_strdup_vprintf().
 253  *
 254  * In versions of GLib prior to 1.2.3, this function may return -1 if the
 255  * output was truncated, and the truncated string may not be nul-terminated.
 256  * In versions prior to 1.3.12, this function returns the length of the output
 257  * string.
 258  *
 259  * The return value of g_vsnprintf() conforms to the vsnprintf() function
 260  * as standardized in ISO C99. Note that this is different from traditional
 261  * vsnprintf(), which returns the length of the output string.
 262  *
 263  * The format string may contain positional parameters, as specified in
 264  * the Single Unix Specification.
 265  *
 266  * Returns: the number of bytes which would be produced if the buffer
 267  *  was large enough.
 268  */
 269 gint
 270 g_vsnprintf (gchar       *string,
 271              gulong       n,
 272              gchar const *format,
 273              va_list      args)
 274 {
 275   g_return_val_if_fail (n == 0 || string != NULL, -1);
 276   g_return_val_if_fail (format != NULL, -1);
 277
 278   return _g_vsnprintf (string, n, format, args);
 279 }
 280
 281 /**
 282  * g_vasprintf:
 283  * @string: the return location for the newly-allocated string.
 284  * @format: a standard printf() format string, but notice
 285  *          <link linkend="string-precision">string precision pitfalls</link>.
 286  * @args: the list of arguments to insert in the output.
 287  *
 288  * An implementation of the GNU vasprintf() function which supports
 289  * positional parameters, as specified in the Single Unix Specification.
 290  * This function is similar to g_vsprintf(), except that it allocates a
 291  * string to hold the output, instead of putting the output in a buffer
 292  * you allocate in advance.
 293  *
 294  * Returns: the number of bytes printed.
 295  *
 296  * Since: 2.4
 297  **/
 298 gint
 299 g_vasprintf (gchar      **string,
 300              gchar const *format,
 301              va_list      args)
 302 {
 303   gint len;
 304   g_return_val_if_fail (string != NULL, -1);
 305
 306 #if !defined(HAVE_GOOD_PRINTF)
 307
 308   len = _g_gnulib_vasprintf (string, format, args);
 309   if (len < 0)
 310     *string = NULL;
 311
 312 #elif defined (HAVE_VASPRINTF)
 313
 314   len = vasprintf (string, format, args);
 315   if (len < 0)
 316     *string = NULL;
 317   else if (!g_mem_is_system_malloc ())
 318     {
 319       /* vasprintf returns malloc-allocated memory */
 320       gchar *string1 = g_strndup (*string, len);
 321       free (*string);
 322       *string = string1;
 323     }
 324
 325 #else
 326
 327   {
 328     va_list args2;
 329
 330     G_VA_COPY (args2, args);
 331
 332     *string = g_new (gchar, g_printf_string_upper_bound (format, args));
 333
 334     len = _g_vsprintf (*string, format, args2);
 335     va_end (args2);
 336   }
 337 #endif
 338
 339   return len;
 340 }