stdlib/fmtmsg.c

   1 /* Copyright (C) 1997-2021 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <fmtmsg.h>
  20 #include <libc-lock.h>
  21 #include <stdio.h>
  22 #include <stdint.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <sys/syslog.h>
  26 #include <wchar.h>
  27
  28
  29 /* We have global data, protect the modification.  */
  30 __libc_lock_define_initialized (static, lock)
  31
  32
  33 enum
  34 {
  35   label_mask = 0x01,
  36   severity_mask = 0x02,
  37   text_mask = 0x04,
  38   action_mask = 0x08,
  39   tag_mask = 0x10,
  40   all_mask = label_mask | severity_mask | text_mask | action_mask | tag_mask
  41 };
  42
  43 static const struct
  44 {
  45   uint32_t len;
  46   /* Adjust the size if new elements are added.  */
  47   const char name[12];
  48 } keywords[] =
  49   {
  50     { 5, "label" },
  51     { 8, "severity" },
  52     { 4, "text" },
  53     { 6, "action"},
  54     { 3, "tag" }
  55   };
  56 #define NKEYWORDS (sizeof (keywords) / sizeof (keywords[0]))
  57
  58
  59 struct severity_info
  60 {
  61   int severity;
  62   const char *string;
  63   struct severity_info *next;
  64 };
  65
  66
  67 /* List of known severities.  */
  68 static const struct severity_info nosev =
  69 {
  70   MM_NOSEV, "", NULL
  71 };
  72 static const struct severity_info haltsev =
  73 {
  74   MM_HALT, "HALT", (struct severity_info *) &nosev
  75 };
  76 static const struct severity_info errorsev =
  77 {
  78   MM_ERROR, "ERROR", (struct severity_info *) &haltsev
  79 };
  80 static const struct severity_info warningsev =
  81 {
  82   MM_WARNING, "WARNING", (struct severity_info *) &errorsev
  83 };
  84 static const struct severity_info infosev =
  85 {
  86   MM_INFO, "INFO", (struct severity_info *) &warningsev
  87 };
  88
  89 /* Start of the list.  */
  90 static struct severity_info *severity_list = (struct severity_info *) &infosev;
  91
  92 /* Mask of values we will print.  */
  93 static int print;
  94
  95 /* Prototypes for local functions.  */
  96 static void init (void);
  97 static int internal_addseverity (int severity, const char *string);
  98
  99
 100 int
 101 fmtmsg (long int classification, const char *label, int severity,
 102         const char *text, const char *action, const char *tag)
 103 {
 104   __libc_once_define (static, once);
 105   struct severity_info *severity_rec;
 106
 107   /* Make sure everything is initialized.  */
 108   __libc_once (once, init);
 109
 110   /* Start the real work.  First check whether the input is ok.  */
 111   if (label != MM_NULLLBL)
 112     {
 113       /* Must be two fields, separated by a colon.  */
 114       const char *cp = strchr (label, ':');
 115       if (cp == NULL)
 116         return MM_NOTOK;
 117
 118       /* The first field must not contain more than 10 bytes.  */
 119       if (cp - label > 10
 120           /* The second field must not have more than 14 bytes.  */
 121           || strlen (cp + 1) > 14)
 122         return MM_NOTOK;
 123     }
 124
 125   /* We do not want this call to be cut short by a thread
 126      cancellation.  Therefore disable cancellation for now.  */
 127   int state = PTHREAD_CANCEL_ENABLE;
 128   __pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &state);
 129
 130   __libc_lock_lock (lock);
 131
 132   for (severity_rec = severity_list; severity_rec != NULL;
 133        severity_rec = severity_rec->next)
 134     if (severity == severity_rec->severity)
 135       /* Bingo.  */
 136       break;
 137
 138   /* If we don't know anything about the severity level return an error.  */
 139   int result = MM_NOTOK;
 140   if (severity_rec != NULL)
 141     {
 142       result = MM_OK;
 143
 144       /* Now we can print.  */
 145       if (classification & MM_PRINT)
 146         {
 147           int do_label = (print & label_mask) && label != MM_NULLLBL;
 148           int do_severity = (print & severity_mask) && severity != MM_NULLSEV;
 149           int do_text = (print & text_mask) && text != MM_NULLTXT;
 150           int do_action = (print & action_mask) && action != MM_NULLACT;
 151           int do_tag = (print & tag_mask) && tag != MM_NULLTAG;
 152           int need_colon = (do_label
 153                             && (do_severity | do_text | do_action | do_tag));
 154
 155           if (__fxprintf (stderr, "%s%s%s%s%s%s%s%s%s%s\n",
 156                           do_label ? label : "",
 157                           need_colon ? ": " : "",
 158                           do_severity ? severity_rec->string : "",
 159                           do_severity && (do_text | do_action | do_tag)
 160                           ? ": " : "",
 161                           do_text ? text : "",
 162                           do_text && (do_action | do_tag) ? "\n" : "",
 163                           do_action ? "TO FIX: " : "",
 164                           do_action ? action : "",
 165                           do_action && do_tag ? "  " : "",
 166                           do_tag ? tag : "") < 0)
 167             /* Oh, oh.  An error occurred during the output.  */
 168             result = MM_NOMSG;
 169         }
 170
 171       if (classification & MM_CONSOLE)
 172         {
 173           int do_label = label != MM_NULLLBL;
 174           int do_severity = severity != MM_NULLSEV;
 175           int do_text = text != MM_NULLTXT;
 176           int do_action = action != MM_NULLACT;
 177           int do_tag = tag != MM_NULLTAG;
 178           int need_colon = (do_label
 179                             && (do_severity | do_text | do_action | do_tag));
 180
 181           syslog (LOG_ERR, "%s%s%s%s%s%s%s%s%s%s\n",
 182                   do_label ? label : "",
 183                   need_colon ? ": " : "",
 184                   do_severity ? severity_rec->string : "",
 185                   do_severity && (do_text | do_action | do_tag) ? ": " : "",
 186                   do_text ? text : "",
 187                   do_text && (do_action | do_tag) ? "\n" : "",
 188                   do_action ? "TO FIX: " : "",
 189                   do_action ? action : "",
 190                   do_action && do_tag ? "  " : "",
 191                   do_tag ? tag : "");
 192         }
 193     }
 194
 195   __libc_lock_unlock (lock);
 196
 197   __pthread_setcancelstate (state, NULL);
 198
 199   return result;
 200 }
 201
 202
 203 /* Initialize from environment variable content.  */
 204 static void
 205 init (void)
 206 {
 207   const char *msgverb_var = getenv ("MSGVERB");
 208   const char *sevlevel_var = getenv ("SEV_LEVEL");
 209
 210   if (msgverb_var != NULL && msgverb_var[0] != '\0')
 211     {
 212       /* Using this extra variable allows us to work without locking.  */
 213       do
 214         {
 215           size_t cnt;
 216
 217           for (cnt = 0; cnt < NKEYWORDS; ++cnt)
 218             if (memcmp (msgverb_var,
 219                         keywords[cnt].name, keywords[cnt].len) == 0
 220                 && (msgverb_var[keywords[cnt].len] == ':'
 221                     || msgverb_var[keywords[cnt].len] == '\0'))
 222               break;
 223
 224           if (cnt < NKEYWORDS)
 225             {
 226               print |= 1 << cnt;
 227
 228               msgverb_var += keywords[cnt].len;
 229               if (msgverb_var[0] == ':')
 230                 ++msgverb_var;
 231             }
 232           else
 233             {
 234               /* We found an illegal keyword in the environment
 235                  variable.  The specifications say that we print all
 236                  fields.  */
 237               print = all_mask;
 238               break;
 239             }
 240         }
 241       while (msgverb_var[0] != '\0');
 242     }
 243   else
 244     print = all_mask;
 245
 246
 247   if (sevlevel_var != NULL)
 248     {
 249       __libc_lock_lock (lock);
 250
 251       while (sevlevel_var[0] != '\0')
 252         {
 253           const char *end = __strchrnul (sevlevel_var, ':');
 254           int level;
 255
 256           /* First field: keyword.  This is not used here but it must be
 257              present.  */
 258           while (sevlevel_var < end)
 259             if (*sevlevel_var++ == ',')
 260               break;
 261
 262           if (sevlevel_var < end)
 263             {
 264               /* Second field: severity level, a number.  */
 265               char *cp;
 266
 267               level = strtol (sevlevel_var, &cp, 0);
 268               if (cp != sevlevel_var && cp < end && *cp++ == ','
 269                   && level > MM_INFO)
 270                 {
 271                   const char *new_string;
 272
 273                   new_string = __strndup (cp, end - cp);
 274
 275                   if (new_string != NULL
 276                       && (internal_addseverity (level, new_string)
 277                           != MM_OK))
 278                     free ((char *) new_string);
 279                 }
 280             }
 281
 282           sevlevel_var = end + (*end == ':' ? 1 : 0);
 283         }
 284
 285       __libc_lock_unlock (lock);
 286     }
 287 }
 288
 289
 290 /* Add the new entry to the list.  */
 291 static int
 292 internal_addseverity (int severity, const char *string)
 293 {
 294   struct severity_info *runp, *lastp;
 295   int result = MM_OK;
 296
 297   /* First see if there is already a record for the severity level.  */
 298   for (runp = severity_list, lastp = NULL; runp != NULL; runp = runp->next)
 299     if (runp->severity == severity)
 300       break;
 301     else
 302       lastp = runp;
 303
 304   if (runp != NULL)
 305     {
 306       if (string != NULL)
 307         /* Change the string.  */
 308         runp->string = string;
 309       else
 310         {
 311           /* Remove the severity class.  */
 312           if (lastp == NULL)
 313             severity_list = runp->next;
 314           else
 315             lastp->next = runp->next;
 316
 317           free (runp);
 318         }
 319     }
 320   else if (string != NULL)
 321     {
 322       runp = malloc (sizeof (*runp));
 323       if (runp == NULL)
 324         result = MM_NOTOK;
 325       else
 326         {
 327           runp->severity = severity;
 328           runp->next = severity_list;
 329           runp->string = string;
 330           severity_list = runp;
 331         }
 332     }
 333   else
 334     /* We tried to remove a non-existing severity class.  */
 335     result = MM_NOTOK;
 336
 337   return result;
 338 }
 339
 340
 341 /* Add new severity level or remove old one.  */
 342 int
 343 __addseverity (int severity, const char *string)
 344 {
 345   int result;
 346
 347   /* Prevent illegal SEVERITY values.  */
 348   if (severity <= MM_INFO)
 349     return MM_NOTOK;
 350
 351   /* Protect the global data.  */
 352   __libc_lock_lock (lock);
 353
 354   /* Do the real work.  */
 355   result = internal_addseverity (severity, string);
 356
 357   /* Release the lock.  */
 358   __libc_lock_unlock (lock);
 359
 360   return result;
 361 }
 362 weak_alias (__addseverity, addseverity)
 363
 364
 365 libc_freeres_fn (free_mem)
 366 {
 367   struct severity_info *runp = severity_list;
 368
 369   while (runp != NULL)
 370     if (runp->severity > MM_INFO)
 371       {
 372         /* This is data we have to release.  */
 373         struct severity_info *here = runp;
 374         runp = runp->next;
 375         free (here);
 376       }
 377     else
 378       runp = runp->next;
 379 }