external/ibm-public/postfix/dist/src/util/vstream.h

   1 /*      $NetBSD$        */
   2
   3 #ifndef _VSTREAM_H_INCLUDED_
   4 #define _VSTREAM_H_INCLUDED_
   5
   6 /*++
   7 /* NAME
   8 /*      vstream 3h
   9 /* SUMMARY
  10 /*      simple buffered I/O package
  11 /* SYNOPSIS
  12 /*      #include <vstream.h>
  13 /* DESCRIPTION
  14 /* .nf
  15
  16  /*
  17   * System library.
  18   */
  19 #include <sys/time.h>
  20 #include <time.h>
  21 #include <fcntl.h>
  22 #include <stdarg.h>
  23 #include <setjmp.h>
  24 #include <unistd.h>
  25
  26  /*
  27   * Utility library.
  28   */
  29 #include <vbuf.h>
  30
  31  /*
  32   * Simple buffered stream. The members of this structure are not part of the
  33   * official interface and can change without prior notice.
  34   */
  35 typedef ssize_t (*VSTREAM_FN) (int, void *, size_t, int, void *);
  36 typedef int (*VSTREAM_WAITPID_FN) (pid_t, WAIT_STATUS_T *, int);
  37
  38 #ifdef NO_SIGSETJMP
  39 #define VSTREAM_JMP_BUF jmp_buf
  40 #else
  41 #define VSTREAM_JMP_BUF sigjmp_buf
  42 #endif
  43
  44 typedef struct VSTREAM {
  45     VBUF    buf;                        /* generic intelligent buffer */
  46     int     fd;                         /* file handle, no 256 limit */
  47     VSTREAM_FN read_fn;                 /* buffer fill action */
  48     VSTREAM_FN write_fn;                /* buffer fill action */
  49     void   *context;                    /* application context */
  50     off_t   offset;                     /* cached seek info */
  51     char   *path;                       /* give it at least try */
  52     int     read_fd;                    /* read channel (double-buffered) */
  53     int     write_fd;                   /* write channel (double-buffered) */
  54     VBUF    read_buf;                   /* read buffer (double-buffered) */
  55     VBUF    write_buf;                  /* write buffer (double-buffered) */
  56     pid_t   pid;                        /* vstream_popen/close() */
  57     VSTREAM_WAITPID_FN waitpid_fn;      /* vstream_popen/close() */
  58     int     timeout;                    /* read/write timout */
  59     VSTREAM_JMP_BUF *jbuf;              /* exception handling */
  60     struct timeval iotime;              /* time of last fill/flush */
  61     /* At bottom for Postfix 2.4 binary compatibility. */
  62     ssize_t req_bufsize;                /* write buffer size */
  63 } VSTREAM;
  64
  65 extern VSTREAM vstream_fstd[];          /* pre-defined streams */
  66
  67 #define VSTREAM_IN              (&vstream_fstd[0])
  68 #define VSTREAM_OUT             (&vstream_fstd[1])
  69 #define VSTREAM_ERR             (&vstream_fstd[2])
  70
  71 #define VSTREAM_FLAG_ERR        VBUF_FLAG_ERR   /* some I/O error */
  72 #define VSTREAM_FLAG_EOF        VBUF_FLAG_EOF   /* end of file */
  73 #define VSTREAM_FLAG_TIMEOUT    VBUF_FLAG_TIMEOUT       /* timeout error */
  74 #define VSTREAM_FLAG_FIXED      VBUF_FLAG_FIXED /* fixed-size buffer */
  75 #define VSTREAM_FLAG_BAD        VBUF_FLAG_BAD
  76
  77 #define VSTREAM_FLAG_READ       (1<<8)  /* read buffer */
  78 #define VSTREAM_FLAG_WRITE      (1<<9)  /* write buffer */
  79 #define VSTREAM_FLAG_SEEK       (1<<10) /* seek info valid */
  80 #define VSTREAM_FLAG_NSEEK      (1<<11) /* can't seek this file */
  81 #define VSTREAM_FLAG_DOUBLE     (1<<12) /* double buffer */
  82
  83 #define VSTREAM_PURGE_READ      (1<<0)  /* flush unread data */
  84 #define VSTREAM_PURGE_WRITE     (1<<1)  /* flush unwritten data */
  85 #define VSTREAM_PURGE_BOTH      (VSTREAM_PURGE_READ|VSTREAM_PURGE_WRITE)
  86
  87 #define VSTREAM_BUFSIZE         4096
  88
  89 extern VSTREAM *vstream_fopen(const char *, int, mode_t);
  90 extern int vstream_fclose(VSTREAM *);
  91 extern off_t vstream_fseek(VSTREAM *, off_t, int);
  92 extern off_t vstream_ftell(VSTREAM *);
  93 extern int vstream_fpurge(VSTREAM *, int);
  94 extern int vstream_fflush(VSTREAM *);
  95 extern int vstream_fputs(const char *, VSTREAM *);
  96 extern VSTREAM *vstream_fdopen(int, int);
  97 extern int vstream_fdclose(VSTREAM *);
  98
  99 #define vstream_fread(v, b, n)  vbuf_read(&(v)->buf, (b), (n))
 100 #define vstream_fwrite(v, b, n) vbuf_write(&(v)->buf, (b), (n))
 101
 102 #define VSTREAM_PUTC(ch, vp)    VBUF_PUT(&(vp)->buf, (ch))
 103 #define VSTREAM_GETC(vp)        VBUF_GET(&(vp)->buf)
 104 #define vstream_ungetc(vp, ch)  vbuf_unget(&(vp)->buf, (ch))
 105 #define VSTREAM_EOF             VBUF_EOF
 106
 107 #define VSTREAM_PUTCHAR(ch)     VSTREAM_PUTC((ch), VSTREAM_OUT)
 108 #define VSTREAM_GETCHAR()       VSTREAM_GETC(VSTREAM_IN)
 109
 110 #define vstream_fileno(vp)      ((vp)->fd)
 111 #define vstream_context(vp)     ((vp)->context)
 112 #define vstream_ferror(vp)      vbuf_error(&(vp)->buf)
 113 #define vstream_feof(vp)        vbuf_eof(&(vp)->buf)
 114 #define vstream_ftimeout(vp)    vbuf_timeout(&(vp)->buf)
 115 #define vstream_clearerr(vp)    vbuf_clearerr(&(vp)->buf)
 116 #define VSTREAM_PATH(vp)        ((vp)->path ? (const char *) (vp)->path : "unknown_stream")
 117 #define vstream_ftime(vp)       ((time_t) ((vp)->iotime.tv_sec))
 118 #define vstream_ftimeval(vp)    ((vp)->iotime)
 119
 120 extern void vstream_control(VSTREAM *, int,...);
 121
 122 #define VSTREAM_CTL_END         0
 123 #define VSTREAM_CTL_READ_FN     1
 124 #define VSTREAM_CTL_WRITE_FN    2
 125 #define VSTREAM_CTL_PATH        3
 126 #define VSTREAM_CTL_DOUBLE      4
 127 #define VSTREAM_CTL_READ_FD     5
 128 #define VSTREAM_CTL_WRITE_FD    6
 129 #define VSTREAM_CTL_WAITPID_FN  7
 130 #define VSTREAM_CTL_TIMEOUT     8
 131 #define VSTREAM_CTL_EXCEPT      9
 132 #define VSTREAM_CTL_CONTEXT     10
 133 #ifdef F_DUPFD
 134 #define VSTREAM_CTL_DUPFD       11
 135 #endif
 136 #define VSTREAM_CTL_BUFSIZE     12
 137
 138 extern VSTREAM *PRINTFLIKE(1, 2) vstream_printf(const char *,...);
 139 extern VSTREAM *PRINTFLIKE(2, 3) vstream_fprintf(VSTREAM *, const char *,...);
 140
 141 extern VSTREAM *vstream_popen(int,...);
 142 extern int vstream_pclose(VSTREAM *);
 143
 144 #define vstream_ispipe(vp)      ((vp)->pid != 0)
 145
 146 #define VSTREAM_POPEN_END       0       /* terminator */
 147 #define VSTREAM_POPEN_COMMAND   1       /* command is string */
 148 #define VSTREAM_POPEN_ARGV      2       /* command is array */
 149 #define VSTREAM_POPEN_UID       3       /* privileges */
 150 #define VSTREAM_POPEN_GID       4       /* privileges */
 151 #define VSTREAM_POPEN_ENV       5       /* extra environment */
 152 #define VSTREAM_POPEN_SHELL     6       /* alternative shell */
 153 #define VSTREAM_POPEN_WAITPID_FN 7      /* child catcher, waitpid() compat. */
 154 #define VSTREAM_POPEN_EXPORT    8       /* exportable environment */
 155
 156 extern VSTREAM *vstream_vfprintf(VSTREAM *, const char *, va_list);
 157
 158 extern ssize_t vstream_peek(VSTREAM *);
 159 extern ssize_t vstream_bufstat(VSTREAM *, int);
 160
 161 #define VSTREAM_BST_FLAG_IN             (1<<0)
 162 #define VSTREAM_BST_FLAG_OUT            (1<<1)
 163 #define VSTREAM_BST_FLAG_PEND           (1<<2)
 164
 165 #define VSTREAM_BST_MASK_DIR    (VSTREAM_BST_FLAG_IN | VSTREAM_BST_FLAG_OUT)
 166 #define VSTREAM_BST_IN_PEND     (VSTREAM_BST_FLAG_IN | VSTREAM_BST_FLAG_PEND)
 167 #define VSTREAM_BST_OUT_PEND    (VSTREAM_BST_FLAG_OUT | VSTREAM_BST_FLAG_PEND)
 168
 169 #define vstream_peek(vp) vstream_bufstat((vp), VSTREAM_BST_IN_PEND)
 170
 171  /*
 172   * Exception handling. We use pointer to jmp_buf to avoid a lot of unused
 173   * baggage for streams that don't need this functionality.
 174   *
 175   * XXX sigsetjmp()/siglongjmp() save and restore the signal mask which can
 176   * avoid surprises in code that manipulates signals, but unfortunately some
 177   * systems have bugs in their implementation.
 178   */
 179 #ifdef NO_SIGSETJMP
 180 #define vstream_setjmp(stream)          setjmp((stream)->jbuf[0])
 181 #define vstream_longjmp(stream, val)    longjmp((stream)->jbuf[0], (val))
 182 #else
 183 #define vstream_setjmp(stream)          sigsetjmp((stream)->jbuf[0], 1)
 184 #define vstream_longjmp(stream, val)    siglongjmp((stream)->jbuf[0], (val))
 185 #endif
 186
 187  /*
 188   * Tweaks and workarounds.
 189   */
 190 extern int vstream_tweak_sock(VSTREAM *);
 191 extern int vstream_tweak_tcp(VSTREAM *);
 192
 193 /* LICENSE
 194 /* .ad
 195 /* .fi
 196 /*      The Secure Mailer license must be distributed with this software.
 197 /* AUTHOR(S)
 198 /*      Wietse Venema
 199 /*      IBM T.J. Watson Research
 200 /*      P.O. Box 704
 201 /*      Yorktown Heights, NY 10598, USA
 202 /*--*/
 203
 204 #endif