usr/src/cmd/sendmail/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 #pragma ident   "%Z%%M% %I%     %E% SMI"
  18
  19 /*
  20 **  Information local to this implementation of stdio,
  21 **  in particular, macros and private variables.
  22 */
  23
  24 #include <sm/time.h>
  25 #if !SM_CONF_MEMCHR
  26 # include <memory.h>
  27 #endif /* !SM_CONF_MEMCHR */
  28 #include <sm/heap.h>
  29
  30 int     sm_flush __P((SM_FILE_T *, int *));
  31 SM_FILE_T       *smfp __P((void));
  32 int     sm_refill __P((SM_FILE_T *, int));
  33 void    sm_init __P((void));
  34 void    sm_cleanup __P((void));
  35 void    sm_makebuf __P((SM_FILE_T *));
  36 int     sm_whatbuf __P((SM_FILE_T *, size_t *, int *));
  37 int     sm_fwalk __P((int (*)(SM_FILE_T *, int *), int *));
  38 int     sm_wsetup __P((SM_FILE_T *));
  39 int     sm_flags __P((int));
  40 SM_FILE_T       *sm_fp __P((const SM_FILE_T *, const int, SM_FILE_T *));
  41 int     sm_vprintf __P((int, char const *, va_list));
  42
  43 /* std io functions */
  44 ssize_t sm_stdread __P((SM_FILE_T *, char *, size_t));
  45 ssize_t sm_stdwrite __P((SM_FILE_T *, char const *, size_t));
  46 off_t   sm_stdseek __P((SM_FILE_T *, off_t, int));
  47 int     sm_stdclose __P((SM_FILE_T *));
  48 int     sm_stdopen __P((SM_FILE_T *, const void *, int, const void *));
  49 int     sm_stdfdopen __P((SM_FILE_T *, const void *, int, const void *));
  50 int     sm_stdsetinfo __P((SM_FILE_T *, int , void *));
  51 int     sm_stdgetinfo __P((SM_FILE_T *, int , void *));
  52
  53 /* stdio io functions */
  54 ssize_t sm_stdioread __P((SM_FILE_T *, char *, size_t));
  55 ssize_t sm_stdiowrite __P((SM_FILE_T *, char const *, size_t));
  56 off_t   sm_stdioseek __P((SM_FILE_T *, off_t, int));
  57 int     sm_stdioclose __P((SM_FILE_T *));
  58 int     sm_stdioopen __P((SM_FILE_T *, const void *, int, const void *));
  59 int     sm_stdiosetinfo __P((SM_FILE_T *, int , void *));
  60 int     sm_stdiogetinfo __P((SM_FILE_T *, int , void *));
  61
  62 /* string io functions */
  63 ssize_t sm_strread __P((SM_FILE_T *, char *, size_t));
  64 ssize_t sm_strwrite __P((SM_FILE_T *, char const *, size_t));
  65 off_t   sm_strseek __P((SM_FILE_T *, off_t, int));
  66 int     sm_strclose __P((SM_FILE_T *));
  67 int     sm_stropen __P((SM_FILE_T *, const void *, int, const void *));
  68 int     sm_strsetinfo __P((SM_FILE_T *, int , void *));
  69 int     sm_strgetinfo __P((SM_FILE_T *, int , void *));
  70
  71 /* syslog io functions */
  72 ssize_t sm_syslogread __P((SM_FILE_T *, char *, size_t));
  73 ssize_t sm_syslogwrite __P((SM_FILE_T *, char const *, size_t));
  74 off_t   sm_syslogseek __P((SM_FILE_T *, off_t, int));
  75 int     sm_syslogclose __P((SM_FILE_T *));
  76 int     sm_syslogopen __P((SM_FILE_T *, const void *, int, const void *));
  77 int     sm_syslogsetinfo __P((SM_FILE_T *, int , void *));
  78 int     sm_sysloggetinfo __P((SM_FILE_T *, int , void *));
  79
  80 extern bool Sm_IO_DidInit;
  81
  82 /* Return true iff the given SM_FILE_T cannot be written now. */
  83 #define cantwrite(fp) \
  84         ((((fp)->f_flags & SMWR) == 0 || (fp)->f_bf.smb_base == NULL) && \
  85          sm_wsetup(fp))
  86
  87 /*
  88 **  Test whether the given stdio file has an active ungetc buffer;
  89 **   release such a buffer, without restoring ordinary unread data.
  90 */
  91
  92 #define HASUB(fp) ((fp)->f_ub.smb_base != NULL)
  93 #define FREEUB(fp)                                      \
  94 {                                                       \
  95         if ((fp)->f_ub.smb_base != (fp)->f_ubuf)        \
  96                 sm_free((char *)(fp)->f_ub.smb_base);   \
  97         (fp)->f_ub.smb_base = NULL;                     \
  98 }
  99
 100 extern const char SmFileMagic[];
 101
 102 #define SM_ALIGN(p)     (((unsigned long)(p) + SM_ALIGN_BITS) & ~SM_ALIGN_BITS)
 103
 104 #define sm_io_flockfile(fp)     ((void) 0)
 105 #define sm_io_funlockfile(fp)   ((void) 0)
 106
 107 int sm_flags __P((int));
 108
 109 #ifndef FDSET_CAST
 110 # define FDSET_CAST             /* empty cast for fd_set arg to select */
 111 #endif
 112
 113 /*
 114 **  SM_CONVERT_TIME -- convert the API timeout flag for select() usage.
 115 **
 116 **      This takes a 'fp' (a file type pointer) and obtains the "raw"
 117 **      file descriptor (fd) if possible. The 'fd' is needed to possibly
 118 **      switch the mode of the file (blocking/non-blocking) to match
 119 **      the type of timeout. If timeout is SM_TIME_FOREVER then the
 120 **      timeout using select won't be needed and the file is best placed
 121 **      in blocking mode. If there is to be a finite timeout then the file
 122 **      is best placed in non-blocking mode. Then, if not enough can be
 123 **      written, select() can be used to test when something can be written
 124 **      yet still timeout if the wait is too long.
 125 **      If the mode is already in the correct state we don't change it.
 126 **      Iff (yes "iff") the 'fd' is "-1" in value then the mode change
 127 **      will not happen. This situation arises when a late-binding-to-disk
 128 **      file type is in use. An example of this is the sendmail buffered
 129 **      file type (in sendmail/bf.c).
 130 **
 131 **      Parameters
 132 **              fp -- the file pointer the timeout is for
 133 **              fd -- to become the file descriptor value from 'fp'
 134 **              val -- the timeout value to be converted
 135 **              time -- a struct timeval holding the converted value
 136 **
 137 **      Returns
 138 **              nothing, this is flow-through code
 139 **
 140 **      Side Effects:
 141 **              May or may not change the mode of a currently open file.
 142 **              The file mode may be changed to O_NONBLOCK or ~O_NONBLOCK
 143 **              (meaning block). This is done to best match the type of
 144 **              timeout and for (possible) use with select().
 145 */
 146
 147 # define SM_CONVERT_TIME(fp, fd, val, time) { \
 148         if (((fd) = sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL)) == -1) \
 149         { \
 150                 /* can't get an fd, likely internal 'fake' fp */ \
 151                 errno = 0; \
 152         } \
 153         if ((val) == SM_TIME_DEFAULT) \
 154                 (val) = (fp)->f_timeout; \
 155         if ((val) == SM_TIME_IMMEDIATE || (val) == SM_TIME_FOREVER) \
 156         { \
 157                 (time)->tv_sec = 0; \
 158                 (time)->tv_usec = 0; \
 159         } \
 160         else \
 161         { \
 162                 (time)->tv_sec = (val) / 1000; \
 163                 (time)->tv_usec = ((val) - ((time)->tv_sec * 1000)) * 1000; \
 164         } \
 165         if ((val) == SM_TIME_FOREVER) \
 166         { \
 167                 if ((fp)->f_timeoutstate == SM_TIME_NONBLOCK && (fd) != -1) \
 168                 { \
 169                         int ret; \
 170                         ret = fcntl((fd), F_GETFL, 0); \
 171                         if (ret == -1 || fcntl((fd), F_SETFL, \
 172                                                ret & ~O_NONBLOCK) == -1) \
 173                         { \
 174                                 /* errno should be set */ \
 175                                 return SM_IO_EOF; \
 176                         } \
 177                         (fp)->f_timeoutstate = SM_TIME_BLOCK; \
 178                         if ((fp)->f_modefp != NULL) \
 179                                 (fp)->f_modefp->f_timeoutstate = SM_TIME_BLOCK; \
 180                 } \
 181         } \
 182         else { \
 183                 if ((fp)->f_timeoutstate == SM_TIME_BLOCK && (fd) != -1) \
 184                 { \
 185                         int ret; \
 186                         ret = fcntl((fd), F_GETFL, 0); \
 187                         if (ret == -1 || fcntl((fd), F_SETFL, \
 188                                                ret | O_NONBLOCK) == -1) \
 189                         { \
 190                                 /* errno should be set */ \
 191                                 return SM_IO_EOF; \
 192                         } \
 193                         (fp)->f_timeoutstate = SM_TIME_NONBLOCK; \
 194                         if ((fp)->f_modefp != NULL) \
 195                                 (fp)->f_modefp->f_timeoutstate = SM_TIME_NONBLOCK; \
 196                 } \
 197         } \
 198 }
 199
 200 /*
 201 **  SM_IO_WR_TIMEOUT -- setup the timeout for the write
 202 **
 203 **  This #define uses a select() to wait for the 'fd' to become writable.
 204 **  The select() can be active for up to 'to' time. The select may not
 205 **  use all of the the 'to' time. Hence, the amount of "wall-clock" time is
 206 **  measured to decide how much to subtract from 'to' to update it. On some
 207 **  BSD-based/like systems the timeout for a select is updated for the
 208 **  amount of time used. On many/most systems this does not happen. Therefore
 209 **  the updating of 'to' must be done ourselves; a copy of 'to' is passed
 210 **  since a BSD-like system will have updated it and we don't want to
 211 **  double the time used!
 212 **  Note: if a valid 'fd' doesn't exist yet, don't use this (e.g. the
 213 **  sendmail buffered file type in sendmail/bf.c; see fvwrite.c).
 214 **
 215 **      Parameters
 216 **              fd -- a file descriptor for doing select() with
 217 **              timeout -- the original user set value.
 218 **
 219 **      Returns
 220 **              nothing, this is flow through code
 221 **
 222 **      Side Effects:
 223 **              adjusts 'timeout' for time used
 224 */
 225
 226 #define SM_IO_WR_TIMEOUT(fp, fd, to) { \
 227         struct timeval sm_io_to_before, sm_io_to_after, sm_io_to_diff; \
 228         struct timeval sm_io_to; \
 229         int sm_io_to_sel; \
 230         fd_set sm_io_to_mask, sm_io_x_mask; \
 231         errno = 0; \
 232         if ((to) == SM_TIME_DEFAULT) \
 233                 (to) = (fp)->f_timeout; \
 234         if ((to) == SM_TIME_IMMEDIATE) \
 235         { \
 236                 errno = EAGAIN; \
 237                 return SM_IO_EOF; \
 238         } \
 239         else if ((to) == SM_TIME_FOREVER) \
 240         { \
 241                 errno = EINVAL; \
 242                 return SM_IO_EOF; \
 243         } \
 244         else \
 245         { \
 246                 sm_io_to.tv_sec = (to) / 1000; \
 247                 sm_io_to.tv_usec = ((to) - (sm_io_to.tv_sec * 1000)) * 1000; \
 248         } \
 249         if (FD_SETSIZE > 0 && (fd) >= FD_SETSIZE) \
 250         { \
 251                 errno = EINVAL; \
 252                 return SM_IO_EOF; \
 253         } \
 254         FD_ZERO(&sm_io_to_mask); \
 255         FD_SET((fd), &sm_io_to_mask); \
 256         FD_ZERO(&sm_io_x_mask); \
 257         FD_SET((fd), &sm_io_x_mask); \
 258         if (gettimeofday(&sm_io_to_before, NULL) < 0) \
 259                 return SM_IO_EOF; \
 260         do \
 261         {       \
 262                 sm_io_to_sel = select((fd) + 1, NULL, &sm_io_to_mask, \
 263                                         &sm_io_x_mask, &sm_io_to); \
 264         } while (sm_io_to_sel < 0 && errno == EINTR); \
 265         if (sm_io_to_sel < 0) \
 266         { \
 267                 /* something went wrong, errno set */ \
 268                 return SM_IO_EOF; \
 269         } \
 270         else if (sm_io_to_sel == 0) \
 271         { \
 272                 /* timeout */ \
 273                 errno = EAGAIN; \
 274                 return SM_IO_EOF; \
 275         } \
 276         /* else loop again */ \
 277         if (gettimeofday(&sm_io_to_after, NULL) < 0) \
 278                 return SM_IO_EOF; \
 279         timersub(&sm_io_to_after, &sm_io_to_before, &sm_io_to_diff); \
 280         (to) -= (sm_io_to_diff.tv_sec * 1000); \
 281         (to) -= (sm_io_to_diff.tv_usec / 1000); \
 282         if ((to) < 0) \
 283                 (to) = 0; \
 284 }
 285
 286 /*
 287 **  If there is no 'fd' just error (we can't timeout). If the timeout
 288 **  is SM_TIME_FOREVER then there is no need to do a timeout with
 289 **  select since this will be a real error.  If the error is not
 290 **  EAGAIN/EWOULDBLOCK (from a nonblocking) then it's a real error.
 291 **  Specify the condition here as macro so it can be used in several places.
 292 */
 293
 294 #define IS_IO_ERROR(fd, ret, to) \
 295         ((fd) < 0 ||    \
 296          ((ret) < 0 && errno != EAGAIN && errno != EWOULDBLOCK) ||      \
 297          (to) == SM_TIME_FOREVER)
 298