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 2.1 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, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "config.h"
  19
  20 #include <stdarg.h>
  21 #include <stdlib.h>
  22 #include <stdio.h>
  23
  24 #include "gprintf.h"
  25 #include "gprintfint.h"
  26
  27
  28 /**
  29  * g_printf:
  30  * @format: a standard printf() format string, but notice
  31  *          [string precision pitfalls][string-precision]
  32  * @...: the arguments to insert in the output.
  33  *
  34  * An implementation of the standard printf() function which supports
  35  * positional parameters, as specified in the Single Unix Specification.
  36  *
  37  * As with the standard printf(), this does not automatically append a trailing
  38  * new-line character to the message, so typically @format should end with its
  39  * own new-line character.
  40  *
  41  * `glib/gprintf.h` must be explicitly included in order to use this function.
  42  *
  43  * Returns: the number of bytes printed.
  44  *
  45  * Since: 2.2
  46  **/
  47 gint
  48 g_printf (gchar const *format,
  49           ...)
  50 {
  51   va_list args;
  52   gint retval;
  53
  54   va_start (args, format);
  55   retval = g_vprintf (format, args);
  56   va_end (args);
  57
  58   return retval;
  59 }
  60
  61 /**
  62  * g_fprintf:
  63  * @file: (not nullable): the stream to write to.
  64  * @format: a standard printf() format string, but notice
  65  *          [string precision pitfalls][string-precision]
  66  * @...: the arguments to insert in the output.
  67  *
  68  * An implementation of the standard fprintf() function which supports
  69  * positional parameters, as specified in the Single Unix Specification.
  70  *
  71  * `glib/gprintf.h` must be explicitly included in order to use this function.
  72  *
  73  * Returns: the number of bytes printed.
  74  *
  75  * Since: 2.2
  76  **/
  77 gint
  78 g_fprintf (FILE        *file,
  79            gchar const *format,
  80            ...)
  81 {
  82   va_list args;
  83   gint retval;
  84
  85   va_start (args, format);
  86   retval = g_vfprintf (file, format, args);
  87   va_end (args);
  88
  89   return retval;
  90 }
  91
  92 /**
  93  * g_sprintf:
  94  * @string: A pointer to a memory buffer to contain the resulting string. It
  95  *          is up to the caller to ensure that the allocated buffer is large
  96  *          enough to hold the formatted result
  97  * @format: a standard printf() format string, but notice
  98  *          [string precision pitfalls][string-precision]
  99  * @...: the arguments to insert in the output.
 100  *
 101  * An implementation of the standard sprintf() function which supports
 102  * positional parameters, as specified in the Single Unix Specification.
 103  *
 104  * Note that it is usually better to use g_snprintf(), to avoid the
 105  * risk of buffer overflow.
 106  *
 107  * `glib/gprintf.h` must be explicitly included in order to use this function.
 108  *
 109  * See also g_strdup_printf().
 110  *
 111  * Returns: the number of bytes printed.
 112  *
 113  * Since: 2.2
 114  **/
 115 gint
 116 g_sprintf (gchar       *string,
 117            gchar const *format,
 118            ...)
 119 {
 120   va_list args;
 121   gint retval;
 122
 123   va_start (args, format);
 124   retval = g_vsprintf (string, format, args);
 125   va_end (args);
 126
 127   return retval;
 128 }
 129
 130 /**
 131  * g_snprintf:
 132  * @string: the buffer to hold the output.
 133  * @n: the maximum number of bytes to produce (including the
 134  *     terminating nul character).
 135  * @format: a standard printf() format string, but notice
 136  *          [string precision pitfalls][string-precision]
 137  * @...: the arguments to insert in the output.
 138  *
 139  * A safer form of the standard sprintf() function. The output is guaranteed
 140  * to not exceed @n characters (including the terminating nul character), so
 141  * it is easy to ensure that a buffer overflow cannot occur.
 142  *
 143  * See also g_strdup_printf().
 144  *
 145  * In versions of GLib prior to 1.2.3, this function may return -1 if the
 146  * output was truncated, and the truncated string may not be nul-terminated.
 147  * In versions prior to 1.3.12, this function returns the length of the output
 148  * string.
 149  *
 150  * The return value of g_snprintf() conforms to the snprintf()
 151  * function as standardized in ISO C99. Note that this is different from
 152  * traditional snprintf(), which returns the length of the output string.
 153  *
 154  * The format string may contain positional parameters, as specified in
 155  * the Single Unix Specification.
 156  *
 157  * Returns: the number of bytes which would be produced if the buffer
 158  *     was large enough.
 159  **/
 160 gint
 161 g_snprintf (gchar       *string,
 162             gulong       n,
 163             gchar const *format,
 164             ...)
 165 {
 166   va_list args;
 167   gint retval;
 168
 169   va_start (args, format);
 170   retval = g_vsnprintf (string, n, format, args);
 171   va_end (args);
 172
 173   return retval;
 174 }
 175
 176 /**
 177  * g_vprintf:
 178  * @format: a standard printf() format string, but notice
 179  *          [string precision pitfalls][string-precision]
 180  * @args: the list of arguments to insert in the output.
 181  *
 182  * An implementation of the standard vprintf() function which supports
 183  * positional parameters, as specified in the Single Unix Specification.
 184  *
 185  * `glib/gprintf.h` must be explicitly included in order to use this function.
 186  *
 187  * Returns: the number of bytes printed.
 188  *
 189  * Since: 2.2
 190  **/
 191 gint
 192 g_vprintf (gchar const *format,
 193            va_list      args)
 194 {
 195   g_return_val_if_fail (format != NULL, -1);
 196
 197   return _g_vprintf (format, args);
 198 }
 199
 200 /**
 201  * g_vfprintf:
 202  * @file: (not nullable): the stream to write to.
 203  * @format: a standard printf() format string, but notice
 204  *          [string precision pitfalls][string-precision]
 205  * @args: the list of arguments to insert in the output.
 206  *
 207  * An implementation of the standard fprintf() function which supports
 208  * positional parameters, as specified in the Single Unix Specification.
 209  *
 210  * `glib/gprintf.h` must be explicitly included in order to use this function.
 211  *
 212  * Returns: the number of bytes printed.
 213  *
 214  * Since: 2.2
 215  **/
 216 gint
 217 g_vfprintf (FILE        *file,
 218             gchar const *format,
 219             va_list      args)
 220 {
 221   g_return_val_if_fail (format != NULL, -1);
 222
 223   return _g_vfprintf (file, format, args);
 224 }
 225
 226 /**
 227  * g_vsprintf:
 228  * @string: the buffer to hold the output.
 229  * @format: a standard printf() format string, but notice
 230  *          [string precision pitfalls][string-precision]
 231  * @args: the list of arguments to insert in the output.
 232  *
 233  * An implementation of the standard vsprintf() function which supports
 234  * positional parameters, as specified in the Single Unix Specification.
 235  *
 236  * `glib/gprintf.h` must be explicitly included in order to use this function.
 237  *
 238  * Returns: the number of bytes printed.
 239  *
 240  * Since: 2.2
 241  **/
 242 gint
 243 g_vsprintf (gchar        *string,
 244             gchar const *format,
 245             va_list      args)
 246 {
 247   g_return_val_if_fail (string != NULL, -1);
 248   g_return_val_if_fail (format != NULL, -1);
 249
 250   return _g_vsprintf (string, format, args);
 251 }
 252
 253 /**
 254  * g_vsnprintf:
 255  * @string: the buffer to hold the output.
 256  * @n: the maximum number of bytes to produce (including the
 257  *     terminating nul character).
 258  * @format: a standard printf() format string, but notice
 259  *          string precision pitfalls][string-precision]
 260  * @args: the list of arguments to insert in the output.
 261  *
 262  * A safer form of the standard vsprintf() function. The output is guaranteed
 263  * to not exceed @n characters (including the terminating nul character), so
 264  * it is easy to ensure that a buffer overflow cannot occur.
 265  *
 266  * See also g_strdup_vprintf().
 267  *
 268  * In versions of GLib prior to 1.2.3, this function may return -1 if the
 269  * output was truncated, and the truncated string may not be nul-terminated.
 270  * In versions prior to 1.3.12, this function returns the length of the output
 271  * string.
 272  *
 273  * The return value of g_vsnprintf() conforms to the vsnprintf() function
 274  * as standardized in ISO C99. Note that this is different from traditional
 275  * vsnprintf(), which returns the length of the output string.
 276  *
 277  * The format string may contain positional parameters, as specified in
 278  * the Single Unix Specification.
 279  *
 280  * Returns: the number of bytes which would be produced if the buffer
 281  *  was large enough.
 282  */
 283 gint
 284 g_vsnprintf (gchar       *string,
 285              gulong       n,
 286              gchar const *format,
 287              va_list      args)
 288 {
 289   g_return_val_if_fail (n == 0 || string != NULL, -1);
 290   g_return_val_if_fail (format != NULL, -1);
 291
 292   return _g_vsnprintf (string, n, format, args);
 293 }
 294
 295 /**
 296  * g_vasprintf:
 297  * @string: the return location for the newly-allocated string.
 298  * @format: a standard printf() format string, but notice
 299  *          [string precision pitfalls][string-precision]
 300  * @args: the list of arguments to insert in the output.
 301  *
 302  * An implementation of the GNU vasprintf() function which supports
 303  * positional parameters, as specified in the Single Unix Specification.
 304  * This function is similar to g_vsprintf(), except that it allocates a
 305  * string to hold the output, instead of putting the output in a buffer
 306  * you allocate in advance.
 307  *
 308  * `glib/gprintf.h` must be explicitly included in order to use this function.
 309  *
 310  * Returns: the number of bytes printed.
 311  *
 312  * Since: 2.4
 313  **/
 314 gint
 315 g_vasprintf (gchar      **string,
 316              gchar const *format,
 317              va_list      args)
 318 {
 319   gint len;
 320   g_return_val_if_fail (string != NULL, -1);
 321
 322 #if !defined(HAVE_GOOD_PRINTF)
 323
 324   len = _g_gnulib_vasprintf (string, format, args);
 325   if (len < 0)
 326     *string = NULL;
 327
 328 #elif defined (HAVE_VASPRINTF)
 329
 330   len = vasprintf (string, format, args);
 331   if (len < 0)
 332     *string = NULL;
 333
 334 #else
 335
 336   {
 337     va_list args2;
 338
 339     G_VA_COPY (args2, args);
 340
 341     *string = g_new (gchar, g_printf_string_upper_bound (format, args));
 342
 343     len = _g_vsprintf (*string, format, args2);
 344     va_end (args2);
 345   }
 346 #endif
 347
 348   return len;
 349 }