libguile/deprecation.c

   1 /* Copyright (C) 2001, 2006, 2010, 2011 Free Software Foundation, Inc.
   2  *
   3  * This library is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public License
   5  * as published by the Free Software Foundation; either version 3 of
   6  * the License, or (at your option) any later version.
   7  *
   8  * This library is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301 USA
  17  */
  18
  19 \f
  20
  21 #ifdef HAVE_CONFIG_H
  22 #  include <config.h>
  23 #endif
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdarg.h>
  28
  29 #include "libguile/_scm.h"
  30
  31 #include "libguile/deprecation.h"
  32 #include "libguile/strings.h"
  33 #include "libguile/ports.h"
  34
  35 #include "libguile/private-options.h"
  36
  37 \f
  38
  39 struct issued_warning {
  40   struct issued_warning *prev;
  41   const char *message;
  42 };
  43
  44 static scm_i_pthread_mutex_t warn_lock = SCM_I_PTHREAD_MUTEX_INITIALIZER;
  45 static struct issued_warning *issued_warnings;
  46 static int print_summary = 0;
  47
  48 void
  49 scm_c_issue_deprecation_warning (const char *msg)
  50 {
  51   if (!SCM_WARN_DEPRECATED)
  52     print_summary = 1;
  53   else
  54     {
  55       struct issued_warning *iw;
  56
  57       scm_i_pthread_mutex_lock (&warn_lock);
  58       for (iw = issued_warnings; iw; iw = iw->prev)
  59         if (!strcmp (iw->message, msg))
  60           {
  61             msg = NULL;
  62             break;
  63           }
  64       if (msg)
  65         {
  66           msg = strdup (msg);
  67           iw = malloc (sizeof (struct issued_warning));
  68           if (msg == NULL || iw == NULL)
  69             /* Nothing sensible to do if you can't allocate this small
  70                amount of memory.  */
  71             abort ();
  72           iw->message = msg;
  73           iw->prev = issued_warnings;
  74           issued_warnings = iw;
  75         }
  76       scm_i_pthread_mutex_unlock (&warn_lock);
  77
  78       /* All this dance is to avoid printing to a port inside a mutex,
  79          which could recurse and deadlock.  */
  80       if (msg)
  81         {
  82           if (scm_gc_running_p)
  83             fprintf (stderr, "%s\n", msg);
  84           else
  85             {
  86               scm_puts_unlocked (msg, scm_current_warning_port ());
  87               scm_newline (scm_current_warning_port ());
  88             }
  89         }
  90     }
  91 }
  92
  93 void
  94 scm_c_issue_deprecation_warning_fmt (const char *msg, ...)
  95 {
  96   va_list ap;
  97   char buf[512];
  98
  99   va_start (ap, msg);
 100   vsnprintf (buf, 511, msg, ap);
 101   va_end (ap);
 102   buf[511] = '\0';
 103   scm_c_issue_deprecation_warning (buf);
 104 }
 105
 106 SCM_DEFINE(scm_issue_deprecation_warning,
 107            "issue-deprecation-warning", 0, 0, 1,
 108            (SCM msgs),
 109            "Output @var{msgs} to @code{(current-error-port)} when this "
 110            "is the first call to @code{issue-deprecation-warning} with "
 111            "this specific @var{msgs}.  Do nothing otherwise. "
 112            "The argument @var{msgs} should be a list of strings; "
 113            "they are printed in turn, each one followed by a newline.")
 114 #define FUNC_NAME s_scm_issue_deprecation_warning
 115 {
 116   if (!SCM_WARN_DEPRECATED)
 117     print_summary = 1;
 118   else
 119     {
 120       SCM nl = scm_from_locale_string ("\n");
 121       SCM msgs_nl = SCM_EOL;
 122       char *c_msgs;
 123       while (scm_is_pair (msgs))
 124         {
 125           if (!scm_is_null (msgs_nl))
 126             msgs_nl = scm_cons (nl, msgs_nl);
 127           msgs_nl = scm_cons (SCM_CAR (msgs), msgs_nl);
 128           msgs = SCM_CDR (msgs);
 129         }
 130       msgs_nl = scm_string_append (scm_reverse_x (msgs_nl, SCM_EOL));
 131       c_msgs = scm_to_locale_string (msgs_nl);
 132       scm_c_issue_deprecation_warning (c_msgs);
 133       free (c_msgs);
 134     }
 135   return SCM_UNSPECIFIED;
 136 }
 137 #undef FUNC_NAME
 138
 139 static void
 140 print_deprecation_summary (void)
 141 {
 142   if (print_summary)
 143     {
 144       fputs ("\n"
 145              "Some deprecated features have been used.  Set the environment\n"
 146              "variable GUILE_WARN_DEPRECATED to \"detailed\" and rerun the\n"
 147              "program to get more information.  Set it to \"no\" to suppress\n"
 148              "this message.\n", stderr);
 149     }
 150 }
 151
 152 SCM_DEFINE(scm_include_deprecated_features,
 153            "include-deprecated-features", 0, 0, 0,
 154            (),
 155            "Return @code{#t} iff deprecated features should be included "
 156            "in public interfaces.")
 157 #define FUNC_NAME s_scm_include_deprecated_features
 158 {
 159   return scm_from_bool (SCM_ENABLE_DEPRECATED == 1);
 160 }
 161 #undef FUNC_NAME
 162
 163
 164 \f
 165
 166 void
 167 scm_init_deprecation ()
 168 {
 169   const char *level = getenv ("GUILE_WARN_DEPRECATED");
 170   if (level == NULL)
 171     level = SCM_WARN_DEPRECATED_DEFAULT;
 172   if (!strcmp (level, "detailed"))
 173     SCM_WARN_DEPRECATED = 1;
 174   else if (!strcmp (level, "no"))
 175     SCM_WARN_DEPRECATED = 0;
 176   else
 177     {
 178       SCM_WARN_DEPRECATED = 0;
 179       atexit (print_deprecation_summary);
 180     }
 181 #include "libguile/deprecation.x"
 182 }
 183
 184 /*
 185   Local Variables:
 186   c-file-style: "gnu"
 187   End:
 188  */