contrib/sendmail-8.14/libsm/local.h

   1 /*
   2  * Copyright (c) 2000-2002, 2004-2006 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  * Copyright (c) 1990, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Chris Torek.
   9  *
  10  * By using this file, you agree to the terms and conditions set
  11  * forth in the LICENSE file which can be found at the top level of
  12  * the sendmail distribution.
  13  *
  14  *      $Id: local.h,v 1.58 2006/12/19 19:44:23 ca Exp $
  15  */
  16
  17 /*
  18 **  Information local to this implementation of stdio,
  19 **  in particular, macros and private variables.
  20 */
  21
  22 #include <sm/time.h>
  23 #if !SM_CONF_MEMCHR
  24 # include <memory.h>
  25 #endif /* !SM_CONF_MEMCHR */
  26 #include <sm/heap.h>
  27
  28 int     sm_flush __P((SM_FILE_T *, int *));
  29 SM_FILE_T       *smfp __P((void));
  30 int     sm_refill __P((SM_FILE_T *, int));
  31 void    sm_init __P((void));
  32 void    sm_cleanup __P((void));
  33 void    sm_makebuf __P((SM_FILE_T *));
  34 int     sm_whatbuf __P((SM_FILE_T *, size_t *, int *));
  35 int     sm_fwalk __P((int (*)(SM_FILE_T *, int *), int *));
  36 int     sm_wsetup __P((SM_FILE_T *));
  37 int     sm_flags __P((int));
  38 SM_FILE_T       *sm_fp __P((const SM_FILE_T *, const int, SM_FILE_T *));
  39 int     sm_vprintf __P((int, char const *, va_list));
  40
  41 /* std io functions */
  42 ssize_t sm_stdread __P((SM_FILE_T *, char *, size_t));
  43 ssize_t sm_stdwrite __P((SM_FILE_T *, char const *, size_t));
  44 off_t   sm_stdseek __P((SM_FILE_T *, off_t, int));
  45 int     sm_stdclose __P((SM_FILE_T *));
  46 int     sm_stdopen __P((SM_FILE_T *, const void *, int, const void *));
  47 int     sm_stdfdopen __P((SM_FILE_T *, const void *, int, const void *));
  48 int     sm_stdsetinfo __P((SM_FILE_T *, int , void *));
  49 int     sm_stdgetinfo __P((SM_FILE_T *, int , void *));
  50
  51 /* stdio io functions */
  52 ssize_t sm_stdioread __P((SM_FILE_T *, char *, size_t));
  53 ssize_t sm_stdiowrite __P((SM_FILE_T *, char const *, size_t));
  54 off_t   sm_stdioseek __P((SM_FILE_T *, off_t, int));
  55 int     sm_stdioclose __P((SM_FILE_T *));
  56 int     sm_stdioopen __P((SM_FILE_T *, const void *, int, const void *));
  57 int     sm_stdiosetinfo __P((SM_FILE_T *, int , void *));
  58 int     sm_stdiogetinfo __P((SM_FILE_T *, int , void *));
  59
  60 /* string io functions */
  61 ssize_t sm_strread __P((SM_FILE_T *, char *, size_t));
  62 ssize_t sm_strwrite __P((SM_FILE_T *, char const *, size_t));
  63 off_t   sm_strseek __P((SM_FILE_T *, off_t, int));
  64 int     sm_strclose __P((SM_FILE_T *));
  65 int     sm_stropen __P((SM_FILE_T *, const void *, int, const void *));
  66 int     sm_strsetinfo __P((SM_FILE_T *, int , void *));
  67 int     sm_strgetinfo __P((SM_FILE_T *, int , void *));
  68
  69 /* syslog io functions */
  70 ssize_t sm_syslogread __P((SM_FILE_T *, char *, size_t));
  71 ssize_t sm_syslogwrite __P((SM_FILE_T *, char const *, size_t));
  72 off_t   sm_syslogseek __P((SM_FILE_T *, off_t, int));
  73 int     sm_syslogclose __P((SM_FILE_T *));
  74 int     sm_syslogopen __P((SM_FILE_T *, const void *, int, const void *));
  75 int     sm_syslogsetinfo __P((SM_FILE_T *, int , void *));
  76 int     sm_sysloggetinfo __P((SM_FILE_T *, int , void *));
  77
  78 extern bool Sm_IO_DidInit;
  79
  80 /* Return true iff the given SM_FILE_T cannot be written now. */
  81 #define cantwrite(fp) \
  82         ((((fp)->f_flags & SMWR) == 0 || (fp)->f_bf.smb_base == NULL) && \
  83          sm_wsetup(fp))
  84
  85 /*
  86 **  Test whether the given stdio file has an active ungetc buffer;
  87 **   release such a buffer, without restoring ordinary unread data.
  88 */
  89
  90 #define HASUB(fp) ((fp)->f_ub.smb_base != NULL)
  91 #define FREEUB(fp)                                      \
  92 {                                                       \
  93         if ((fp)->f_ub.smb_base != (fp)->f_ubuf)        \
  94                 sm_free((char *)(fp)->f_ub.smb_base);   \
  95         (fp)->f_ub.smb_base = NULL;                     \
  96 }
  97
  98 extern const char SmFileMagic[];
  99
 100 #define SM_ALIGN(p)     (((unsigned long)(p) + SM_ALIGN_BITS) & ~SM_ALIGN_BITS)
 101
 102 #define sm_io_flockfile(fp)     ((void) 0)
 103 #define sm_io_funlockfile(fp)   ((void) 0)
 104
 105 int sm_flags __P((int));
 106
 107 #ifndef FDSET_CAST
 108 # define FDSET_CAST             /* empty cast for fd_set arg to select */
 109 #endif
 110
 111 /*
 112 **  SM_CONVERT_TIME -- convert the API timeout flag for select() usage.
 113 **
 114 **      This takes a 'fp' (a file type pointer) and obtains the "raw"
 115 **      file descriptor (fd) if possible. The 'fd' is needed to possibly
 116 **      switch the mode of the file (blocking/non-blocking) to match
 117 **      the type of timeout. If timeout is SM_TIME_FOREVER then the
 118 **      timeout using select won't be needed and the file is best placed
 119 **      in blocking mode. If there is to be a finite timeout then the file
 120 **      is best placed in non-blocking mode. Then, if not enough can be
 121 **      written, select() can be used to test when something can be written
 122 **      yet still timeout if the wait is too long.
 123 **      If the mode is already in the correct state we don't change it.
 124 **      Iff (yes "iff") the 'fd' is "-1" in value then the mode change
 125 **      will not happen. This situation arises when a late-binding-to-disk
 126 **      file type is in use. An example of this is the sendmail buffered
 127 **      file type (in sendmail/bf.c).
 128 **
 129 **      Parameters
 130 **              fp -- the file pointer the timeout is for
 131 **              fd -- to become the file descriptor value from 'fp'
 132 **              val -- the timeout value to be converted
 133 **              time -- a struct timeval holding the converted value
 134 **
 135 **      Returns
 136 **              nothing, this is flow-through code
 137 **
 138 **      Side Effects:
 139 **              May or may not change the mode of a currently open file.
 140 **              The file mode may be changed to O_NONBLOCK or ~O_NONBLOCK
 141 **              (meaning block). This is done to best match the type of
 142 **              timeout and for (possible) use with select().
 143 */
 144
 145 # define SM_CONVERT_TIME(fp, fd, val, time) { \
 146         if (((fd) = sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL)) == -1) \
 147         { \
 148                 /* can't get an fd, likely internal 'fake' fp */ \
 149                 errno = 0; \
 150         } \
 151         if ((val) == SM_TIME_DEFAULT) \
 152                 (val) = (fp)->f_timeout; \
 153         if ((val) == SM_TIME_IMMEDIATE || (val) == SM_TIME_FOREVER) \
 154         { \
 155                 (time)->tv_sec = 0; \
 156                 (time)->tv_usec = 0; \
 157         } \
 158         else \
 159         { \
 160                 (time)->tv_sec = (val) / 1000; \
 161                 (time)->tv_usec = ((val) - ((time)->tv_sec * 1000)) * 1000; \
 162         } \
 163         if ((val) == SM_TIME_FOREVER) \
 164         { \
 165                 if ((fp)->f_timeoutstate == SM_TIME_NONBLOCK && (fd) != -1) \
 166                 { \
 167                         int ret; \
 168                         ret = fcntl((fd), F_GETFL, 0); \
 169                         if (ret == -1 || fcntl((fd), F_SETFL, \
 170                                                ret & ~O_NONBLOCK) == -1) \
 171                         { \
 172                                 /* errno should be set */ \
 173                                 return SM_IO_EOF; \
 174                         } \
 175                         (fp)->f_timeoutstate = SM_TIME_BLOCK; \
 176                         if ((fp)->f_modefp != NULL) \
 177                                 (fp)->f_modefp->f_timeoutstate = SM_TIME_BLOCK; \
 178                 } \
 179         } \
 180         else { \
 181                 if ((fp)->f_timeoutstate == SM_TIME_BLOCK && (fd) != -1) \
 182                 { \
 183                         int ret; \
 184                         ret = fcntl((fd), F_GETFL, 0); \
 185                         if (ret == -1 || fcntl((fd), F_SETFL, \
 186                                                ret | O_NONBLOCK) == -1) \
 187                         { \
 188                                 /* errno should be set */ \
 189                                 return SM_IO_EOF; \
 190                         } \
 191                         (fp)->f_timeoutstate = SM_TIME_NONBLOCK; \
 192                         if ((fp)->f_modefp != NULL) \
 193                                 (fp)->f_modefp->f_timeoutstate = SM_TIME_NONBLOCK; \
 194                 } \
 195         } \
 196 }
 197
 198 /*
 199 **  SM_IO_WR_TIMEOUT -- setup the timeout for the write
 200 **
 201 **  This #define uses a select() to wait for the 'fd' to become writable.
 202 **  The select() can be active for up to 'to' time. The select may not
 203 **  use all of the the 'to' time. Hence, the amount of "wall-clock" time is
 204 **  measured to decide how much to subtract from 'to' to update it. On some
 205 **  BSD-based/like systems the timeout for a select is updated for the
 206 **  amount of time used. On many/most systems this does not happen. Therefore
 207 **  the updating of 'to' must be done ourselves; a copy of 'to' is passed
 208 **  since a BSD-like system will have updated it and we don't want to
 209 **  double the time used!
 210 **  Note: if a valid 'fd' doesn't exist yet, don't use this (e.g. the
 211 **  sendmail buffered file type in sendmail/bf.c; see fvwrite.c).
 212 **
 213 **      Parameters
 214 **              fd -- a file descriptor for doing select() with
 215 **              timeout -- the original user set value.
 216 **
 217 **      Returns
 218 **              nothing, this is flow through code
 219 **
 220 **      Side Effects:
 221 **              adjusts 'timeout' for time used
 222 */
 223
 224 #define SM_IO_WR_TIMEOUT(fp, fd, to) { \
 225         struct timeval sm_io_to_before, sm_io_to_after, sm_io_to_diff; \
 226         struct timeval sm_io_to; \
 227         int sm_io_to_sel; \
 228         fd_set sm_io_to_mask, sm_io_x_mask; \
 229         errno = 0; \
 230         if ((to) == SM_TIME_DEFAULT) \
 231                 (to) = (fp)->f_timeout; \
 232         if ((to) == SM_TIME_IMMEDIATE) \
 233         { \
 234                 errno = EAGAIN; \
 235                 return SM_IO_EOF; \
 236         } \
 237         else if ((to) == SM_TIME_FOREVER) \
 238         { \
 239                 errno = EINVAL; \
 240                 return SM_IO_EOF; \
 241         } \
 242         else \
 243         { \
 244                 sm_io_to.tv_sec = (to) / 1000; \
 245                 sm_io_to.tv_usec = ((to) - (sm_io_to.tv_sec * 1000)) * 1000; \
 246         } \
 247         if (FD_SETSIZE > 0 && (fd) >= FD_SETSIZE) \
 248         { \
 249                 errno = EINVAL; \
 250                 return SM_IO_EOF; \
 251         } \
 252         FD_ZERO(&sm_io_to_mask); \
 253         FD_SET((fd), &sm_io_to_mask); \
 254         FD_ZERO(&sm_io_x_mask); \
 255         FD_SET((fd), &sm_io_x_mask); \
 256         if (gettimeofday(&sm_io_to_before, NULL) < 0) \
 257                 return SM_IO_EOF; \
 258         do \
 259         {       \
 260                 sm_io_to_sel = select((fd) + 1, NULL, &sm_io_to_mask, \
 261                                         &sm_io_x_mask, &sm_io_to); \
 262         } while (sm_io_to_sel < 0 && errno == EINTR); \
 263         if (sm_io_to_sel < 0) \
 264         { \
 265                 /* something went wrong, errno set */ \
 266                 return SM_IO_EOF; \
 267         } \
 268         else if (sm_io_to_sel == 0) \
 269         { \
 270                 /* timeout */ \
 271                 errno = EAGAIN; \
 272                 return SM_IO_EOF; \
 273         } \
 274         /* else loop again */ \
 275         if (gettimeofday(&sm_io_to_after, NULL) < 0) \
 276                 return SM_IO_EOF; \
 277         timersub(&sm_io_to_after, &sm_io_to_before, &sm_io_to_diff); \
 278         (to) -= (sm_io_to_diff.tv_sec * 1000); \
 279         (to) -= (sm_io_to_diff.tv_usec / 1000); \
 280         if ((to) < 0) \
 281                 (to) = 0; \
 282 }
 283
 284 /*
 285 **  If there is no 'fd' just error (we can't timeout). If the timeout
 286 **  is SM_TIME_FOREVER then there is no need to do a timeout with
 287 **  select since this will be a real error.  If the error is not
 288 **  EAGAIN/EWOULDBLOCK (from a nonblocking) then it's a real error.
 289 **  Specify the condition here as macro so it can be used in several places.
 290 */
 291
 292 #define IS_IO_ERROR(fd, ret, to) \
 293         ((fd) < 0 ||    \
 294          ((ret) < 0 && errno != EAGAIN && errno != EWOULDBLOCK) ||      \
 295          (to) == SM_TIME_FOREVER)
 296