def.h

   1 /*
   2  * S-nail - a mail user agent derived from Berkeley Mail.
   3  *
   4  * Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
   5  * Copyright (c) 2012 Steffen "Daode" Nurpmeso.
   6  */
   7 /*
   8  * Copyright (c) 1980, 1993
   9  *      The Regents of the University of California.  All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the University of
  22  *      California, Berkeley and its contributors.
  23  * 4. Neither the name of the University nor the names of its contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  */
  39
  40 /*
  41  * Mail -- a mail program
  42  *
  43  * Author: Kurt Shoens (UCB) March 25, 1978
  44  */
  45
  46 #if !defined (NI_MAXHOST) || (NI_MAXHOST) < 1025
  47 #undef  NI_MAXHOST
  48 #define NI_MAXHOST      1025
  49 #endif
  50
  51 #define APPEND                          /* New mail goes to end of mailbox */
  52
  53 /* Is *C* a quoting character (for *quote-fold* compression) */
  54 #define ISQUOTE(C)      ((C) == '>' || (C) == '|')
  55
  56 #define ESCAPE          '~'             /* Default escape for sending */
  57 #ifndef MAXPATHLEN
  58 #ifdef  PATH_MAX
  59 #define MAXPATHLEN      PATH_MAX
  60 #else
  61 #define MAXPATHLEN      1024
  62 #endif
  63 #endif
  64 #ifndef PATHSIZE
  65 #define PATHSIZE        MAXPATHLEN      /* Size of pathnames throughout */
  66 #endif
  67 #define HSHSIZE         59              /* Hash size for aliases and vars */
  68 #if BUFSIZ > 2560                       /* TODO simply use BUFSIZ? */
  69 # define LINESIZE       BUFSIZ          /* max readable line width */
  70 #else
  71 # define LINESIZE       2560
  72 #endif
  73 #define STRINGSIZE      ((unsigned) 128)/* Dynamic allocation units */
  74 #define MAXARGC         1024            /* Maximum list of raw strings */
  75 #define MAXEXP          25              /* Maximum expansion of aliases */
  76
  77 #undef tr
  78 #ifdef HAVE_CATGETS
  79 # define CATSET                 1
  80 # define tr(c, d)               catgets(catd, CATSET, c, d)
  81 #else
  82 # define catgets(a, b, c, d)    (d)
  83 # define tr(c, d)               (d)
  84 #endif
  85
  86 typedef void (*sighandler_type)(int);
  87
  88 enum okay {
  89         STOP = 0,
  90         OKAY = 1
  91 };
  92
  93 enum mimeenc {
  94         MIME_NONE,                      /* message is not in MIME format */
  95         MIME_BIN,                       /* message is in binary encoding */
  96         MIME_8B,                        /* message is in 8bit encoding */
  97         MIME_7B,                        /* message is in 7bit encoding */
  98         MIME_QP,                        /* message is quoted-printable */
  99         MIME_B64                        /* message is in base64 encoding */
 100 };
 101
 102 enum conversion {
 103         CONV_NONE,                      /* no conversion */
 104         CONV_7BIT,                      /* no conversion, is 7bit */
 105         CONV_FROMQP,                    /* convert from quoted-printable */
 106         CONV_TOQP,                      /* convert to quoted-printable */
 107         CONV_8BIT,                      /* convert to 8bit (iconv) */
 108         CONV_FROMB64,                   /* convert from base64 */
 109         CONV_FROMB64_T,                 /* convert from base64/text */
 110         CONV_TOB64,                     /* convert to base64 */
 111         CONV_FROMHDR,                   /* convert from RFC1522 format */
 112         CONV_TOHDR,                     /* convert to RFC1522 format */
 113         CONV_TOHDR_A                    /* convert addresses for header */
 114 };
 115
 116 enum sendaction {
 117         SEND_MBOX,                      /* no conversion to perform */
 118         SEND_RFC822,                    /* no conversion, no From_ line */
 119         SEND_TODISP,                    /* convert to displayable form */
 120         SEND_TODISP_ALL,                /* same, include all MIME parts */
 121         SEND_SHOW,                      /* convert to 'show' command form */
 122         SEND_TOSRCH,                    /* convert for IMAP SEARCH */
 123         SEND_TOFLTR,                    /* convert for junk mail filtering */
 124         SEND_TOFILE,                    /* convert for saving body to a file */
 125         SEND_TOPIPE,                    /* convert for pipe-content/subc. */
 126         SEND_QUOTE,                     /* convert for quoting */
 127         SEND_QUOTE_ALL,                 /* same, include all MIME parts */
 128         SEND_DECRYPT                    /* decrypt */
 129 };
 130
 131 enum mimecontent {
 132         MIME_UNKNOWN,                   /* unknown content */
 133         MIME_SUBHDR,                    /* inside a multipart subheader */
 134         MIME_822,                       /* message/rfc822 content */
 135         MIME_MESSAGE,                   /* other message/ content */
 136         MIME_TEXT_PLAIN,                /* text/plain content */
 137         MIME_TEXT_HTML,                 /* text/html content */
 138         MIME_TEXT,                      /* other text/ content */
 139         MIME_ALTERNATIVE,               /* multipart/alternative content */
 140         MIME_DIGEST,                    /* multipart/digest content */
 141         MIME_MULTI,                     /* other multipart/ content */
 142         MIME_PKCS7,                     /* PKCS7 content */
 143         MIME_DISCARD                    /* content is discarded */
 144 };
 145
 146 enum mimeclean {
 147         MIME_CLEAN      = 000,          /* plain RFC 2822 message */
 148         MIME_HIGHBIT    = 001,          /* characters >= 0200 */
 149         MIME_LONGLINES  = 002,          /* has lines too long for RFC 2822 */
 150         MIME_CTRLCHAR   = 004,          /* contains control characters */
 151         MIME_HASNUL     = 010,          /* contains \0 characters */
 152         MIME_NOTERMNL   = 020           /* lacks a terminating newline */
 153 };
 154
 155 enum tdflags {
 156         TD_NONE         = 0,    /* no display conversion */
 157         TD_ISPR         = 01,   /* use isprint() checks */
 158         TD_ICONV        = 02,   /* use iconv() */
 159         TD_DELCTRL      = 04    /* delete control characters */
 160 };
 161
 162 struct str {
 163         char *s;                        /* the string's content */
 164         size_t l;                       /* the stings's length */
 165 };
 166
 167 enum protocol {
 168         PROTO_FILE,                     /* refers to a local file */
 169         PROTO_POP3,                     /* is a pop3 server string */
 170         PROTO_IMAP,                     /* is an imap server string */
 171         PROTO_MAILDIR,                  /* refers to a maildir folder */
 172         PROTO_UNKNOWN                   /* unknown protocol */
 173 };
 174
 175 struct sock {                           /* data associated with a socket */
 176         int     s_fd;                   /* file descriptor */
 177 #ifdef  USE_SSL
 178         int     s_use_ssl;              /* SSL is used */
 179 #if defined (USE_NSS)
 180         void    *s_prfd;                /* NSPR file descriptor */
 181 #elif defined (USE_OPENSSL)
 182         void    *s_ssl;                 /* SSL object */
 183         void    *s_ctx;                 /* SSL context object */
 184 #endif  /* SSL library specific */
 185 #endif  /* USE_SSL */
 186         char    *s_wbuf;                /* for buffered writes */
 187         int     s_wbufsize;             /* allocated size of s_buf */
 188         int     s_wbufpos;              /* position of first empty data byte */
 189         char    s_rbuf[LINESIZE+1];     /* for buffered reads */
 190         char    *s_rbufptr;             /* read pointer to s_rbuf */
 191         int     s_rsz;                  /* size of last read in s_rbuf */
 192         char    *s_desc;                /* description of error messages */
 193         void    (*s_onclose)(void);     /* execute on close */
 194 };
 195
 196 struct mailbox {
 197         struct sock     mb_sock;        /* socket structure */
 198         enum {
 199                 MB_NONE         = 000,  /* no reply expected */
 200                 MB_COMD         = 001,  /* command reply expected */
 201                 MB_MULT         = 002,  /* multiline reply expected */
 202                 MB_PREAUTH      = 004,  /* not in authenticated state */
 203                 MB_BYE          = 010   /* may accept a BYE state */
 204         } mb_active;
 205         FILE *mb_itf;                   /* temp file with messages, read open */
 206         FILE *mb_otf;                   /* same, write open */
 207         char *mb_sorted;                /* sort method */
 208         enum {
 209                 MB_VOID,                /* no type (e. g. connection failed) */
 210                 MB_FILE,                /* local file */
 211                 MB_POP3,                /* POP3 mailbox */
 212                 MB_IMAP,                /* IMAP mailbox */
 213                 MB_MAILDIR,             /* maildir folder */
 214                 MB_CACHE                /* cached mailbox */
 215         } mb_type;                      /* type of mailbox */
 216         enum {
 217                 MB_DELE = 01,           /* may delete messages in mailbox */
 218                 MB_EDIT = 02            /* may edit messages in mailbox */
 219         } mb_perm;
 220         int mb_compressed;              /* is a compressed mbox file */
 221         int mb_threaded;                /* mailbox has been threaded */
 222         enum mbflags {
 223                 MB_NOFLAGS      = 000,
 224                 MB_UIDPLUS      = 001   /* supports IMAP UIDPLUS */
 225         } mb_flags;
 226         unsigned long   mb_uidvalidity; /* IMAP unique identifier validity */
 227         char    *mb_imap_account;       /* name of current IMAP account */
 228         char    *mb_imap_mailbox;       /* name of current IMAP mailbox */
 229         char    *mb_cache_directory;    /* name of cache directory */
 230 };
 231
 232 enum needspec {
 233         NEED_UNSPEC,                    /* unspecified need, don't fetch */
 234         NEED_HEADER,                    /* need the header of a message */
 235         NEED_BODY                       /* need header and body of a message */
 236 };
 237
 238 enum havespec {
 239         HAVE_NOTHING = 0,               /* nothing downloaded yet */
 240         HAVE_HEADER = 01,               /* header is downloaded */
 241         HAVE_BODY = 02                  /* entire message is downloaded */
 242 };
 243
 244 /*
 245  * flag bits. Attention: Flags that are used in cache.c may not change.
 246  */
 247 enum mflag {
 248         MUSED           = (1<<0),       /* entry is used, but this bit isn't */
 249         MDELETED        = (1<<1),       /* entry has been deleted */
 250         MSAVED          = (1<<2),       /* entry has been saved */
 251         MTOUCH          = (1<<3),       /* entry has been noticed */
 252         MPRESERVE       = (1<<4),       /* keep entry in sys mailbox */
 253         MMARK           = (1<<5),       /* message is marked! */
 254         MODIFY          = (1<<6),       /* message has been modified */
 255         MNEW            = (1<<7),       /* message has never been seen */
 256         MREAD           = (1<<8),       /* message has been read sometime. */
 257         MSTATUS         = (1<<9),       /* message status has changed */
 258         MBOX            = (1<<10),      /* Send this to mbox, regardless */
 259         MNOFROM         = (1<<11),      /* no From line */
 260         MHIDDEN         = (1<<12),      /* message is hidden to user */
 261         MFULLYCACHED    = (1<<13),      /* message is completely cached */
 262         MBOXED          = (1<<14),      /* message has been sent to mbox */
 263         MUNLINKED       = (1<<15),      /* message was unlinked from cache */
 264         MNEWEST         = (1<<16),      /* message is very new (newmail) */
 265         MFLAG           = (1<<17),      /* message has been flagged recently */
 266         MUNFLAG         = (1<<18),      /* message has been unflagged */
 267         MFLAGGED        = (1<<19),      /* message is `flagged' */
 268         MANSWER         = (1<<20),      /* message has been answered recently */
 269         MUNANSWER       = (1<<21),      /* message has been unanswered */
 270         MANSWERED       = (1<<22),      /* message is `answered' */
 271         MDRAFT          = (1<<23),      /* message has been drafted recently */
 272         MUNDRAFT        = (1<<24),      /* message has been undrafted */
 273         MDRAFTED        = (1<<25),      /* message is marked as `draft' */
 274         MKILL           = (1<<26),      /* message has been killed */
 275         MOLDMARK        = (1<<27),      /* messages was marked previously */
 276         MJUNK           = (1<<28)       /* message is classified as junk */
 277 };
 278
 279 struct mimepart {
 280         enum mflag      m_flag;         /* flags */
 281         enum havespec   m_have;         /* downloaded parts of the part */
 282         int     m_block;                /* block number of this part */
 283         size_t  m_offset;               /* offset in block of part */
 284         size_t  m_size;                 /* Bytes in the part */
 285         size_t  m_xsize;                /* Bytes in the full part */
 286         long    m_lines;                /* Lines in the message */
 287         long    m_xlines;               /* Lines in the full message */
 288         time_t  m_time;                 /* time the message was sent */
 289         char    *m_from;                /* message sender */
 290         struct mimepart *m_nextpart;    /* next part at same level */
 291         struct mimepart *m_multipart;   /* parts of multipart */
 292         struct mimepart *m_parent;      /* enclosing multipart part */
 293         char    *m_ct_type;             /* content-type */
 294         char    *m_ct_type_plain;       /* content-type without specs */
 295         enum mimecontent        m_mimecontent;  /* same in enum */
 296         char    *m_charset;             /* charset */
 297         char    *m_ct_transfer_enc;     /* content-transfer-encoding */
 298         enum mimeenc    m_mimeenc;      /* same in enum */
 299         char    *m_partstring;          /* part level string */
 300         char    *m_filename;            /* attachment filename */
 301 };
 302
 303 struct message {
 304         enum mflag      m_flag;         /* flags */
 305         enum havespec   m_have;         /* downloaded parts of the message */
 306         int     m_block;                /* block number of this message */
 307         size_t  m_offset;               /* offset in block of message */
 308         size_t  m_size;                 /* Bytes in the message */
 309         size_t  m_xsize;                /* Bytes in the full message */
 310         long    m_lines;                /* Lines in the message */
 311         long    m_xlines;               /* Lines in the full message */
 312         time_t  m_time;                 /* time the message was sent */
 313         time_t  m_date;                 /* time in the 'Date' field */
 314         unsigned        m_idhash;       /* hash on Message-ID for threads */
 315         unsigned long   m_uid;          /* IMAP unique identifier */
 316         struct message  *m_child;       /* first child of this message */
 317         struct message  *m_younger;     /* younger brother of this message */
 318         struct message  *m_elder;       /* elder brother of this message */
 319         struct message  *m_parent;      /* parent of this message */
 320         unsigned        m_level;        /* thread level of message */
 321         long            m_threadpos;    /* position in threaded display */
 322         float           m_score;        /* score of message */
 323         char    *m_maildir_file;        /* original maildir file of msg */
 324         unsigned        m_maildir_hash; /* hash of file name in maildir sub */
 325         int     m_collapsed;            /* collapsed thread information */
 326 };
 327
 328 /*
 329  * Given a file address, determine the block number it represents.
 330  */
 331 #define mailx_blockof(off)              ((int) ((off) / 4096))
 332 #define mailx_offsetof(off)             ((int) ((off) % 4096))
 333 #define mailx_positionof(block, offset) ((off_t)(block) * 4096 + (offset))
 334
 335 /*
 336  * Argument types.
 337  */
 338 enum argtype {
 339         MSGLIST = 0,            /* Message list type */
 340         STRLIST = 1,            /* A pure string */
 341         RAWLIST = 2,            /* Shell string list */
 342         NOLIST  = 3,            /* Just plain 0 */
 343         NDMLIST = 4,            /* Message list, no defaults */
 344         ECHOLIST= 5,            /* Like raw list, but keep quote chars */
 345         P       = 040,          /* Autoprint dot after command */
 346         I       = 0100,         /* Interactive command bit */
 347         M       = 0200,         /* Legal from send mode bit */
 348         W       = 0400,         /* Illegal when read only bit */
 349         F       = 01000,        /* Is a conditional command */
 350         T       = 02000,        /* Is a transparent command */
 351         R       = 04000,        /* Cannot be called from collect */
 352         A       = 010000        /* Needs an active mailbox */
 353 };
 354
 355 /*
 356  * Oft-used mask values
 357  */
 358
 359 #define MMNORM          (MDELETED|MSAVED|MHIDDEN)/* Look at both save and delete bits */
 360 #define MMNDEL          (MDELETED|MHIDDEN)      /* Look only at deleted bit */
 361
 362 /*
 363  * Format of the command description table.
 364  * The actual table is declared and initialized
 365  * in lex.c
 366  */
 367 struct cmd {
 368         char    *c_name;                /* Name of command */
 369         int     (*c_func)(void *);      /* Implementor of the command */
 370         enum argtype    c_argtype;      /* Type of arglist (see below) */
 371         short   c_msgflag;              /* Required flags of messages */
 372         short   c_msgmask;              /* Relevant flags of messages */
 373 };
 374
 375 /* Yechh, can't initialize unions */
 376
 377 #define c_minargs c_msgflag             /* Minimum argcount for RAWLIST */
 378 #define c_maxargs c_msgmask             /* Max argcount for RAWLIST */
 379
 380 /*
 381  * Structure used to return a break down of a head
 382  * line (hats off to Bill Joy!)
 383  */
 384
 385 struct headline {
 386         char    *l_from;        /* The name of the sender */
 387         char    *l_tty;         /* His tty string (if any) */
 388         char    *l_date;        /* The entire date string */
 389 };
 390
 391 enum gfield {
 392         GTO     = 1,            /* Grab To: line */
 393         GSUBJECT= 2,            /* Likewise, Subject: line */
 394         GCC     = 4,            /* And the Cc: line */
 395         GBCC    = 8,            /* And also the Bcc: line */
 396
 397         GNL     = 16,           /* Print blank line after */
 398         GDEL    = 32,           /* Entity removed from list */
 399         GCOMMA  = 64,           /* detract puts in commas */
 400         GUA     = 128,          /* User-Agent field */
 401         GMIME   = 256,          /* MIME 1.0 fields */
 402         GMSGID  = 512,          /* a Message-ID */
 403         /*        1024 */       /* unused */
 404         GIDENT  = 2048,         /* From:, Reply-To: and Organization: field */
 405         GREF    = 4096,         /* References: field */
 406         GDATE   = 8192,         /* Date: field */
 407         GFULL   = 16384,        /* include full names */
 408         GSKIN   = 32768,        /* skin names */
 409         GEXTRA  = 65536,        /* extra fields */
 410         GFILES  = 131072        /* include filename addresses */
 411 };
 412
 413 #define GMASK   (GTO|GSUBJECT|GCC|GBCC) /* Mask of places from whence */
 414
 415 #define visible(mp)     (((mp)->m_flag & (MDELETED|MHIDDEN|MKILL)) == 0 || \
 416                                 (dot == (mp) && (mp)->m_flag & MKILL))
 417
 418 /*
 419  * Structure used to pass about the current
 420  * state of the user-typed message header.
 421  */
 422
 423 struct header {
 424         struct name *h_to;              /* Dynamic "To:" string */
 425         char *h_subject;                /* Subject string */
 426         struct name *h_cc;              /* Carbon copies string */
 427         struct name *h_bcc;             /* Blind carbon copies */
 428         struct name *h_ref;             /* References */
 429         struct name *h_smopts;          /* Sendmail options */
 430         struct attachment *h_attach;    /* MIME attachments */
 431         char    *h_charset;             /* preferred charset */
 432         struct name *h_from;            /* overridden "From:" field */
 433         struct name *h_replyto;         /* overridden "Reply-To:" field */
 434         struct name *h_sender;          /* overridden "Sender:" field */
 435         char *h_organization;           /* overridden "Organization:" field */
 436 };
 437
 438 /*
 439  * Structure of namelist nodes used in processing
 440  * the recipients of mail and aliases and all that
 441  * kind of stuff.
 442  */
 443
 444 enum nameflags {
 445         NAME_NAME_SALLOC        = 1<<0, /* .n_name is doped */
 446         NAME_FULLNAME_SALLOC    = 1<<1, /* .n_fullname is doped */
 447         NAME_SKINNED            = 1<<2, /* Is actually skin()ned */
 448         NAME_ADDRSPEC_CHECKED   = 1<<3,
 449         NAME_ADDRSPEC_ISFILE    = 1<<4, /* is a file path */
 450         NAME_ADDRSPEC_ISPIPE    = 1<<5, /* is a command for pipeing */
 451         NAME_ADDRSPEC_ISFILEORPIPE = NAME_ADDRSPEC_ISFILE |
 452                                         NAME_ADDRSPEC_ISPIPE,
 453         NAME_ADDRSPEC_INVALID   = 1<<6, /* An invalid addr-spec */
 454         NAME_ADDRSPEC_ERR_EMPTY = 1<<7, /* An empty string (or NULL) */
 455         NAME_ADDRSPEC_ERR_ATSEQ = 1<<8, /* Weird @ sequence */
 456         /* More on _ERR_ below */
 457         NAME_IDNA               = 1<<9, /* IDNA convertion needed/applied */
 458         /* Bit range for storing a faulty character */
 459         _NAME_ADDRSPEC_ERR_MASKC = 0xFF << 16
 460 };
 461
 462 #define NAME_ADDRSPEC_ERR_GETC(F)       (((F) & 0x00FF0000) >> 16)
 463 #define NAME_ADDRSPEC_ERR_SETC(C)       (((unsigned char)(C) & 0xFF) << 16)
 464
 465 struct name {
 466         struct  name *n_flink;          /* Forward link in list. */
 467         struct  name *n_blink;          /* Backward list link */
 468         enum gfield     n_type;         /* From which list it came */
 469         enum nameflags  n_flags;        /* enum nameflags */
 470         char    *n_name;                /* This fella's name */
 471         char    *n_fullname;            /* Sometimes, name including comment */
 472 };
 473
 474 struct addrguts {
 475         const char      *ag_input;      /* Input string as given */
 476         size_t          ag_ilen;        /* strlen() of input */
 477         size_t          ag_iaddr_start; /* Start of address in .ag_input, */
 478         size_t          ag_iaddr_end;   /* its end (only if ! _FILEADDR) */
 479         char            *ag_skinned;    /* Output (alloced if !=.ag_input) */
 480         size_t          ag_slen;        /* strlen() of .ag_skinned */
 481         size_t          ag_sdom_start;  /* Start of domain in .ag_skinned, */
 482         size_t          ag_sdom_end;    /* its end */
 483         enum nameflags  ag_n_flags;     /* enum nameflags of .ag_skinned */
 484 };
 485
 486 /*
 487  * Structure of a MIME attachment.
 488  */
 489
 490 struct attachment {
 491         struct attachment *a_flink;     /* Forward link in list. */
 492         struct attachment *a_blink;     /* Backward list link */
 493         char    *a_name;                /* file name */
 494         char    *a_content_type;        /* content type */
 495         char    *a_content_disposition; /* content disposition */
 496         char    *a_content_id;          /* content id */
 497         char    *a_content_description; /* content description */
 498         char    *a_charset;             /* character set */
 499         int     a_msgno;                /* message number */
 500 };
 501
 502 /*
 503  * Structure of a variable node.  All variables are
 504  * kept on a singly-linked list of these, rooted by
 505  * "variables"
 506  */
 507
 508 struct var {
 509         struct  var *v_link;            /* Forward link to next variable */
 510         char    *v_name;                /* The variable's name */
 511         char    *v_value;               /* And it's current value */
 512 };
 513
 514 struct group {
 515         struct  group *ge_link;         /* Next person in this group */
 516         char    *ge_name;               /* This person's user name */
 517 };
 518
 519 struct grouphead {
 520         struct  grouphead *g_link;      /* Next grouphead in list */
 521         char    *g_name;                /* Name of this group */
 522         struct  group *g_list;          /* Users in group. */
 523 };
 524
 525 /*
 526  * Structure of the hash table of ignored header fields
 527  */
 528 struct ignoretab {
 529         int i_count;                    /* Number of entries */
 530         struct ignore {
 531                 struct ignore *i_link;  /* Next ignored field in bucket */
 532                 char *i_field;          /* This ignored field */
 533         } *i_head[HSHSIZE];
 534 };
 535
 536 /*
 537  * Token values returned by the scanner used for argument lists.
 538  * Also, sizes of scanner-related things.
 539  */
 540 enum ltoken {
 541         TEOL    = 0,                    /* End of the command line */
 542         TNUMBER = 1,                    /* A message number */
 543         TDASH   = 2,                    /* A simple dash */
 544         TSTRING = 3,                    /* A string (possibly containing -) */
 545         TDOT    = 4,                    /* A "." */
 546         TUP     = 5,                    /* An "^" */
 547         TDOLLAR = 6,                    /* A "$" */
 548         TSTAR   = 7,                    /* A "*" */
 549         TOPEN   = 8,                    /* An '(' */
 550         TCLOSE  = 9,                    /* A ')' */
 551         TPLUS   = 10,                   /* A '+' */
 552         TERROR  = 11,                   /* A lexical error */
 553         TCOMMA  = 12,                   /* A ',' */
 554         TSEMI   = 13,                   /* A ';' */
 555         TBACK   = 14                    /* A '`' */
 556 };
 557
 558 #define REGDEP  2                       /* Maximum regret depth. */
 559
 560 /*
 561  * Constants for conditional commands.  These describe whether
 562  * we should be executing stuff or not.
 563  */
 564 enum condition {
 565         CANY    = 0,    /* Execute in send or receive mode */
 566         CRCV    = 1,    /* Execute in receive mode only */
 567         CSEND   = 2,    /* Execute in send mode only */
 568         CTERM   = 3,    /* Execute only if stdin is a tty */
 569         CNONTERM= 4     /* Execute only if stdin not tty */
 570 };
 571
 572 /*
 573  * For the 'shortcut' and 'unshortcut' functionality.
 574  */
 575 struct shortcut {
 576         struct shortcut *sh_next;       /* next shortcut in list */
 577         char    *sh_short;              /* shortcut string */
 578         char    *sh_long;               /* expanded form */
 579 };
 580
 581 /*
 582  * Kludges to handle the change from setexit / reset to setjmp / longjmp
 583  */
 584
 585 #define setexit()       sigsetjmp(srbuf, 1)
 586 #define reset(x)        siglongjmp(srbuf, x)
 587
 588 /*
 589  * Locale-independent character classes.
 590  */
 591 enum {
 592         C_CNTRL = 0000,
 593         C_BLANK = 0001,
 594         C_WHITE = 0002,
 595         C_SPACE = 0004,
 596         C_PUNCT = 0010,
 597         C_OCTAL = 0020,
 598         C_DIGIT = 0040,
 599         C_UPPER = 0100,
 600         C_LOWER = 0200
 601 };
 602
 603 extern unsigned char const      class_char[];
 604
 605 #define __ischarof(C, FLAGS)    \
 606         (asciichar(C) && (class_char[(unsigned char)(C)] & (FLAGS)) != 0)
 607
 608 #define asciichar(c) ((unsigned char)(c) <= 0177)
 609 #define alnumchar(c) __ischarof(c, C_DIGIT|C_OCTAL|C_UPPER|C_LOWER)
 610 #define alphachar(c) __ischarof(c, C_UPPER|C_LOWER)
 611 #define blankchar(c) __ischarof(c, C_BLANK)
 612 #define blankspacechar(c) __ischarof(c, C_BLANK|C_SPACE)
 613 #define cntrlchar(c) __ischarof(c, C_CNTRL)
 614 #define digitchar(c) __ischarof(c, C_DIGIT|C_OCTAL)
 615 #define lowerchar(c) __ischarof(c, C_LOWER)
 616 #define punctchar(c) __ischarof(c, C_PUNCT)
 617 #define spacechar(c) __ischarof(c, C_BLANK|C_SPACE|C_WHITE)
 618 #define upperchar(c) __ischarof(c, C_UPPER)
 619 #define whitechar(c) __ischarof(c, C_BLANK|C_WHITE)
 620 #define octalchar(c) __ischarof(c, C_OCTAL)
 621
 622 #define upperconv(c) (lowerchar(c) ? (char)((unsigned char)(c)-'a'+'A') : (c))
 623 #define lowerconv(c) (upperchar(c) ? (char)((unsigned char)(c)-'A'+'a') : (c))
 624 /*      RFC 822, 3.2.   */
 625 #define fieldnamechar(c) (asciichar(c)&&(c)>040&&(c)!=0177&&(c)!=':')
 626
 627 /*
 628  * Truncate a file to the last character written. This is
 629  * useful just before closing an old file that was opened
 630  * for read/write.
 631  */
 632 #define trunc(stream) {                                                 \
 633         fflush(stream);                                                 \
 634         ftruncate(fileno(stream), (off_t)ftell(stream));                \
 635 }
 636
 637 /*
 638  * Use either alloca() or smalloc()/free(). ac_alloc can be used to
 639  * allocate space within a function. ac_free must be called when the
 640  * space is no longer needed, but expands to nothing if using alloca().
 641  */
 642 #ifdef  HAVE_ALLOCA
 643 #define ac_alloc(n)     alloca(n)
 644 #define ac_free(n)      do {} while (0)
 645 #else   /* !HAVE_ALLOCA */
 646 #define ac_alloc(n)     smalloc(n)
 647 #define ac_free(n)      free(n)
 648 #endif  /* !HAVE_ALLOCA */
 649
 650 /*
 651  * Single-threaded, use unlocked I/O.
 652  */
 653 #ifdef HAVE_PUTC_UNLOCKED
 654 # undef getc
 655 # define getc(c)        getc_unlocked(c)
 656 # undef putc
 657 # define putc(c, f)     putc_unlocked(c, f)
 658 # undef putchar
 659 # define putchar(c)     putc_unlocked((c), stdout)
 660 #endif
 661
 662 #define CBAD            (-15555)
 663
 664 #define smin(a, b)      ((a) < (b) ? (a) : (b))
 665 #define smax(a, b)      ((a) < (b) ? (b) : (a))
 666
 667 /*
 668  * For saving the current directory and later returning.
 669  */
 670 #ifdef  HAVE_FCHDIR
 671 struct  cw {
 672         int     cw_fd;
 673 };
 674 #else   /* !HAVE_FCHDIR */
 675 struct  cw {
 676         char    cw_wd[PATHSIZE];
 677 };
 678 #endif  /* !HAVE_FCHDIR */
 679
 680 #ifdef  USE_SSL
 681 enum ssl_vrfy_level {
 682         VRFY_IGNORE,
 683         VRFY_WARN,
 684         VRFY_ASK,
 685         VRFY_STRICT
 686 };
 687 #endif  /* USE_SSL */