Look at post instead of inc to determine build options in build_nmh.

[nmh] / sbr / m_getfld.c

diff --git a/sbr/m_getfld.c b/sbr/m_getfld.c
index dc799ba1d0881aff954f3887182eba93a9cd9ddb..45bcebabda08e16d2ded8eb582d821957bd2b527 100644 (file)
--- a/sbr/m_getfld.c
+++ b/sbr/m_getfld.c
@@ -11,6 +11,75 @@
 #include <h/mts.h>
 #include <h/utils.h>
 
 #include <h/mts.h>
 #include <h/utils.h>
 

+/*
+   Purpose
+   =======
+   Reads an Internet message (RFC 5322), or one or more messages
+   stored in a maildrop in mbox (RFC 4155) or MMDF format, from a file
+   stream.  Each call to m_getfld() reads one header field, or a
+   portion of the body, in sequence.
+
+   Inputs
+   ======
+   gstate:  opaque parse state
+   bufsz:  maximum number of characters to load into buf
+   iob:  input file stream
+
+   Outputs
+   =======
+   name:  header field name (array of size NAMESZ=999)
+   buf:  either a header field body or message body
+   bufsz:  number of characters loaded into buf
+   (return value):  message parse state on return from function
+
+   Functions
+   =========
+   void m_getfld_state_destroy (m_getfld_state_t *gstate): destroys
+   the parse state pointed to by the gstate argument.
+
+   m_getfld_state_reset (m_getfld_state_t *gstate): resets the parse
+   state to FLD.
+
+   void m_unknown(FILE *iob):  Determines the message delimiter string
+   for the maildrop.  Called by inc, scan, and msh when reading from a
+   maildrop file.
+
+   void m_eomsbr (int (*action)(int)):  Sets the hook to check for end
+   of message in a maildrop.  Called only by msh.
+
+   State variables
+   ===============
+   m_getfld() retains state internally between calls in the
+   m_getfld_state_t variable.  These are used for detecting the end of
+   each message when reading maildrops:
+
+     char **pat_map
+     char *fdelim
+     char *delimend
+     int fdelimlen
+     char *edelim
+     int edelimlen
+     char *msg_delim
+     int msg_style
+     int (*eom_action)(int)
+
+   Usage
+   =====
+   m_getfld_state_t gstate = 0;
+      ...
+   int state = m_getfld (&gstate, ...);
+      ...
+   m_getfld_state_destroy (&gstate);
+
+   The state is retained internally by gstate.  To reset its state to FLD:
+   m_getfld_state_reset (&gstate);
+*/
+
+/* The following described the old implementation.  The high-level
+   structure hasn't changed, but some of the details have.  I'm
+   leaving this as-is, though, for posterity.
+ */
+

 /* This module has a long and checkered history.  First, it didn't burst
    maildrops correctly because it considered two CTRL-A:s in a row to be
    an inter-message delimiter.  It really is four CTRL-A:s followed by a
 /* This module has a long and checkered history.  First, it didn't burst
    maildrops correctly because it considered two CTRL-A:s in a row to be
    an inter-message delimiter.  It really is four CTRL-A:s followed by a


@@ -134,227 +203,336 @@
    there is data in "name" or "buf").
   */
 
    there is data in "name" or "buf").
   */
 

-/*
-Purpose
-=======
-Reads an Internet message (RFC 5322), or one or more messages stored in a
-maildrop in mbox (RFC 4155) or MMDF format, from a file stream.  Each call
-to m_getfld() reads one header field, or a portion of the body, in sequence.
-
-Inputs
-======
-state:  message parse state
-bufsz:  maximum number of characters to load into buf
-iob:  input file stream
-
-Outputs
-=======
-name:  header field name (array of size NAMESZ=999)
-buf:  either a header field body or message body
-bufsz:  number of characters loaded into buf
-(return value):  message parse state on return from function
-
-Functions
-=========
-void m_unknown(FILE *iob):  Determines the message delimiter string for the
-  maildrop.  Called by inc, scan, and msh when reading from a maildrop file.
-
-void m_eomsbr (int (*action)(int)):  Sets the hook to check for end of
-  message in a maildrop.  Called only by msh.
-
-Those functions save state in the State variables listed below.
-
-State variables
-===============
-m_getfld() retains state internally between calls in some state variables.
-These are used for detecting the end of each message when reading maildrops:
-static unsigned char **pat_map
-static unsigned char *fdelim
-static unsigned char *delimend
-static int fdelimlen
-static unsigned char *edelim
-static int edelimlen
-char * msg_delim
-int msg_style
-int (*eom_action)(int)
-
-Restrictions
-============
-m_getfld() is restricted to operate on one file stream at a time because of
-the retained state (see "State variables" above).  Also, if m_getfld() is
-used to read a file stream, then only m_getfld() should be used to read that
-file stream.
-
-Current usage
-=============
-The first call to m_getfld() on a file stream is with a state of FLD.
-Subsequent calls provide the state returned by the previous call.
-(Therefore, given the Restrictions above, the state variable could be
-removed from the signature and just retained internally.)
-*/
-

 /*
  * static prototypes
  */
 /*
  * static prototypes
  */

-static int m_Eom (int, FILE *);
-static unsigned char *matchc(int, char *, int, char *);
-static unsigned char *locc(int, unsigned char *, unsigned char);
+struct m_getfld_state;
+static int m_Eom (m_getfld_state_t, int);
+static char *matchc(int, char *, int, char *);
+
+#define eom(c,s)       (s->msg_style != MS_DEFAULT && \
+                        (((c) == *s->msg_delim && m_Eom(s,c)) || \
+                         (s->eom_action && (*s->eom_action)(c))))
+
+/* This replaces the old approach, with its direct access to stdio
+ * internals.  It uses one fread() to load a buffer that we manage.
+ *
+ * MSG_INPUT_SIZE is the size of the buffer.
+ * MAX_DELIMITER_SIZE is the maximum size of the delimiter used to
+ * separate messages in a maildrop, such as mbox "From ".
+ *
+ * Some of the tests in the test suite assume a MSG_INPUT_SIZE
+ * of 4096.
+ */
+#define MSG_INPUT_SIZE 4096
+#define MAX_DELIMITER_SIZE 5
+
+struct m_getfld_state {
+    char msg_buf[2 * MSG_INPUT_SIZE + MAX_DELIMITER_SIZE];
+    char *readpos;
+    char *end;  /* One past the last character read in. */
+    /* The following support tracking of the read position in the
+       input file stream so that callers can interleave m_getfld()
+       calls with ftell() and fseek().  ytes_read replaces the old
+       m_getfld() msg_count global.  last_caller_pos is stored when
+       leaving m_getfld()/m_unknown(), then checked on the next entry.
+       last_internal_pos is used to remember the position used
+       internally by m_getfld() (read_more(), actually). */
+    off_t bytes_read;
+    off_t total_bytes_read; /* by caller, not necessarily from input file */
+    off_t last_caller_pos;
+    off_t last_internal_pos;
+    FILE *iob;
+
+    char **pat_map;
+    int msg_style;
+    /*
+     * The "full" delimiter string for a packed maildrop consists
+     * of a newline followed by the actual delimiter.  E.g., the
+     * full string for a Unix maildrop would be: "\n\nFrom ".
+     * "Fdelim" points to the start of the full string and is used
+     * in the BODY case of the main routine to search the buffer for
+     * a possible eom.  Msg_delim points to the first character of
+     * the actual delim. string (i.e., fdelim+1).  Edelim
+     * points to the 2nd character of actual delimiter string.  It
+     * is used in m_Eom because the first character of the string
+     * has been read and matched before m_Eom is called.
+     */
+    char *msg_delim;
+    char *fdelim;
+    char *delimend;
+    int fdelimlen;
+    char *edelim;
+    int edelimlen;
+    int (*eom_action)(int);
+    int state;
+    int track_filepos;
+};
+
+static
+void
+m_getfld_state_init (m_getfld_state_t *gstate, FILE *iob) {
+    m_getfld_state_t s;
+
+    s = *gstate = (m_getfld_state_t) mh_xmalloc(sizeof (struct m_getfld_state));
+    s->readpos = s->end = s->msg_buf;
+    s->bytes_read = s->total_bytes_read = 0;
+    s->last_caller_pos = s->last_internal_pos = 0;
+    s->iob = iob;
+    s->pat_map = NULL;
+    s->msg_style = MS_DEFAULT;
+    s->msg_delim = "";
+    s->fdelim = s->delimend = s->edelim = NULL;
+    s->fdelimlen = s->edelimlen = 0;
+    s->eom_action = NULL;
+    s->state = FLD;
+    s->track_filepos = 0;
+}
+
+/* scan() needs to force a state an initial state of FLD for each message. */
+void
+m_getfld_state_reset (m_getfld_state_t *gstate) {
+    if (*gstate) {
+       (*gstate)->state = FLD;
+    }
+}

 
 

-#define eom(c,iob)     (msg_style != MS_DEFAULT && \
-                        (((c) == *msg_delim && m_Eom(c,iob)) ||\
-                         (eom_action && (*eom_action)(c))))
+/* If the caller interleaves ftell*()/fseek*() calls with m_getfld()
+   calls, m_getfld() must keep track of the file position.  The caller
+   must use this function to inform m_getfld(). */
+void
+m_getfld_track_filepos (m_getfld_state_t *gstate, FILE *iob) {
+    if (! *gstate) {
+       m_getfld_state_init (gstate, iob);
+    }

 
 

-static unsigned char **pat_map;
+    (*gstate)->track_filepos = 1;
+}

 
 

-static int msg_style = MS_DEFAULT;
+void m_getfld_state_destroy (m_getfld_state_t *gstate) {
+    m_getfld_state_t s = *gstate;
+
+    if (s) {
+       if (s->fdelim) free (s->fdelim-1);
+       free (s);
+       *gstate = 0;
+    }
+}

 
 /*
 
 /*

- * The "full" delimiter string for a packed maildrop consists
- * of a newline followed by the actual delimiter.  E.g., the
- * full string for a Unix maildrop would be: "\n\nFrom ".
- * "Fdelim" points to the start of the full string and is used
- * in the BODY case of the main routine to search the buffer for
- * a possible eom.  Msg_delim points to the first character of
- * the actual delim. string (i.e., fdelim+1).  Edelim
- * points to the 2nd character of actual delimiter string.  It
- * is used in m_Eom because the first character of the string
- * has been read and matched before m_Eom is called.
- */
-static char *msg_delim = "";
-static unsigned char *fdelim;
-static unsigned char *delimend;
-static int fdelimlen;
-static unsigned char *edelim;
-static int edelimlen;
-
-static int (*eom_action)(int) = NULL;
-
-/* This replaces the old approach, which included direct access to
-   stdio internals.  It uses one fread() to load a buffer that we
-   manage.
-   MSG_INPUT_SIZE is the size of the buffer.
-   MAX_DELIMITER_SIZE is the maximum size of the delimiter used to
-   separate messages in a maildrop, such as mbox "\nFrom ". */
-#define MSG_INPUT_SIZE 8192
-#define MAX_DELIMITER_SIZE 32
-static struct m_getfld_buffer {
-    unsigned char msg_buf[2 * MSG_INPUT_SIZE + MAX_DELIMITER_SIZE];
-    unsigned char *readpos;
-    unsigned char *end;  /* One past, like C++, the last character read in. */
-} m;
+  Summary of file and message input buffer positions:
+
+  input file      -------------------------------------------EOF
+                                 |              |
+                          last_caller_pos  last_internal_pos
+
+
+  msg_buf                   --------------------EOF
+                            |         |         |
+                         msg_buf   readpos     end
+
+                            |<>|=retained characters, difference
+                                 between last_internal_pos and
+                                 first readpos value after reading
+                                 in new chunk in read_more()
+
+  When returning from m_getfld()/m_unknown():
+  1) Save the internal file position in last_internal_pos.  That's the
+     m_getfld() position reference in the input file.
+  2) Set file stream position so that callers can use ftell().
+
+  When entering m_getfld()/m_unknown():
+  Check to see if the call had changed the file position.  If so,
+  adjust the internal position reference accordingly.  If not, restore
+  the internal file position from last_internal_pos.
+*/
+

 
 static void
 
 static void

-setup_buffer (FILE *iob, struct m_getfld_buffer *m) {
-    /* Rely on Restrictions that m_getfld() calls on different file
-       streams are not interleaved, and no other file stream read
-       methods are used.  And, the first call to m_getfld (), etc., on
-       a stream always reads at least 1 byte.
-       I don't think it's necessary to use ftello() because we just
-       need to determine whether the current offset is 0 or not. */
-    if (ftell (iob) == 0) {
-       /* A new file stream, so reset the buffer state. */
-       m->readpos = m->end = m->msg_buf;
+enter_getfld (m_getfld_state_t *gstate, FILE *iob) {
+    m_getfld_state_t s;
+    off_t pos = ftello (iob);
+
+    if (! *gstate) {
+       m_getfld_state_init (gstate, iob);
+    }
+    s = *gstate;
+    s->bytes_read = 0;
+
+    /* This is ugly and no longer necessary, but is retained just in
+       case it's needed again.  The parser used to open the input file
+       multiple times, so we had to always use the FILE * that's
+       passed to m_getfld().  Now the parser inits a new
+       m_getfld_state for each file.  See comment below about the
+       readpos shift code being currently unused. */
+    s->iob = iob;
+
+    if (s->track_filepos  &&  (pos != 0  ||  s->last_internal_pos != 0)) {
+       if (s->last_internal_pos == 0) {
+           s->total_bytes_read = pos;
+       } else {
+           off_t pos_movement = pos - s->last_caller_pos; /* Can be < 0. */
+
+           if (pos_movement == 0) {
+               pos = s->last_internal_pos;
+           } else {
+               /* The current file stream position differs from the
+                  last one, so caller must have called ftell/o().
+                  Or, this is the first call and the file position
+                  was not at 0. */
+
+               if (s->readpos + pos_movement >= s->msg_buf  &&
+                   s->readpos + pos_movement < s->end) {
+                   /* This is currently unused.  It could be used by
+                      parse_mime() if it was changed to use a global
+                      m_getfld_state. */
+                   /* We can shift readpos and remain within the
+                      bounds of msg_buf. */
+                   s->readpos += pos_movement;
+                   s->total_bytes_read += pos_movement;
+                   pos = s->last_internal_pos;
+               } else {
+                   size_t num_read;
+
+                   /* This seek skips past an integral number of
+                      chunks of size MSG_INPUT_SIZE. */
+                   fseeko (iob, pos/MSG_INPUT_SIZE * MSG_INPUT_SIZE, SEEK_SET);
+                   num_read = fread (s->msg_buf, 1, MSG_INPUT_SIZE, iob);
+                   s->readpos = s->msg_buf  +  pos % MSG_INPUT_SIZE;
+                   s->end = s->msg_buf + num_read;
+                   s->total_bytes_read = pos;
+               }
+           }
+
+           fseeko (iob, pos, SEEK_SET);
+       }
+    }
+}
+
+static void
+leave_getfld (m_getfld_state_t s) {
+    s->total_bytes_read += s->bytes_read;
+
+    if (s->track_filepos) {
+       /* Save the internal file position that we use for the input buffer. */
+       s->last_internal_pos = ftello (s->iob);
+
+       /* Set file stream position so that callers can use ftell(). */
+       fseeko (s->iob, s->total_bytes_read, SEEK_SET);
+       s->last_caller_pos = ftello (s->iob);

     }
 }
 
 static size_t
     }
 }
 
 static size_t

-read_more (struct m_getfld_buffer *m, FILE *iob) {
+read_more (m_getfld_state_t s) {

     /* Retain at least edelimlen characters that have already been
        read so that we can back up to them in m_Eom(). */
     /* Retain at least edelimlen characters that have already been
        read so that we can back up to them in m_Eom(). */

-    ssize_t retain = edelimlen;
+    ssize_t retain = s->edelimlen;

     size_t num_read;
 
     size_t num_read;
 

-    if (m->end > m->readpos) {
-       if (retain < m->end - m->readpos) retain = m->end - m->readpos;
-    }
-    if (retain > m->readpos - m->msg_buf) {
-       /* Should not happen:  there have been fewer characters read
-          than are remaining in the buffer. */
-       retain = m->readpos - m->msg_buf;
-    }
-
-    /* Move any leftover at the end of buf to the beginning. */
-    memmove (m->msg_buf, m->readpos - retain, retain);
+    if (retain < s->end - s->readpos) retain = s->end - s->readpos;
+    assert (retain <= s->readpos - s->msg_buf);

 
 

-    m->readpos = m->msg_buf + retain;
+    /* Move what we want to retain at end of the buffer to the beginning. */
+    memmove (s->msg_buf, s->readpos - retain, retain);

 
 

-    num_read = fread (m->readpos, 1, MSG_INPUT_SIZE, iob);
-
-    m->end = m->readpos + num_read;
+    s->readpos = s->msg_buf + retain;
+    num_read = fread (s->readpos, 1, MSG_INPUT_SIZE, s->iob);
+    s->end = s->readpos + num_read;

 
     return num_read;
 }
 
 
     return num_read;
 }
 

+/* The return values of the following functions are a bit
+   subtle.  They can return 0x00 - 0xff as a valid character,
+   but EOF is typically 0xffffffff. */

 static int
 static int

-Getc (FILE *iob) {
-    if (m.end - m.readpos < 1) {
-       if (read_more (&m, iob) == 0) {
+Getc (m_getfld_state_t s) {
+    if (s->end - s->readpos < 1) {
+       if (read_more (s) == 0) {

            /* Pretend that we read a character.  That's what stdio does. */
            /* Pretend that we read a character.  That's what stdio does. */

-           ++m.readpos;
+           ++s->readpos;

            return EOF;
        }
     }
 
            return EOF;
        }
     }
 

-    return m.readpos < m.end  ?  *m.readpos++  :  EOF;
+    ++s->bytes_read;
+    return s->readpos < s->end  ?  (unsigned char) *s->readpos++  :  EOF;

 }
 
 static int
 }
 
 static int

-Ungetc (int c, FILE *iob) {
-    NMH_UNUSED (iob);
+Peek (m_getfld_state_t s) {
+    if (s->end - s->readpos < 1) {
+       if (read_more (s) == 0) {
+           /* Pretend that we read a character.  That's what stdio does. */
+           ++s->readpos;
+           return EOF;
+       }
+    }
+
+    return s->readpos < s->end  ?  (unsigned char) *s->readpos  :  EOF;
+}

 
 

-    return m.readpos == m.msg_buf  ?  EOF  :  (*--m.readpos = c);
+static int
+Ungetc (int c, m_getfld_state_t s) {
+    if (s->readpos == s->msg_buf) {
+       return EOF;
+    } else {
+       --s->bytes_read;
+       return *--s->readpos = (unsigned char) c;
+    }

 }
 
 
 int
 }
 
 
 int

-m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
-          int *bufsz, FILE *iob)
+m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
+          FILE *iob)

 {
 {

-    register unsigned char  *bp, *cp, *ep, *sp;
-    register int cnt, c, i, j, k;
-    long bytes_read = 0;
+    m_getfld_state_t s;
+    register char *cp;
+    register int max, n, c;

 
 

-    setup_buffer (iob, &m);
+    enter_getfld (gstate, iob);
+    s = *gstate;

 
 

-    if ((c = Getc(iob)) < 0) {
+    if ((c = Getc(s)) < 0) {

        *bufsz = *buf = 0;
        *bufsz = *buf = 0;

-       return FILEEOF;
+       leave_getfld (s);
+       return s->state = FILEEOF;

     }
     }

-    if (eom (c, iob)) {
-       if (! eom_action) {
+    if (eom (c, s)) {
+       if (! s->eom_action) {

            /* flush null messages */
            /* flush null messages */

-           while ((c = Getc(iob)) >= 0 && eom (c, iob))
+           while ((c = Getc(s)) >= 0 && eom (c, s))

                ;
 
            if (c >= 0)
                ;
 
            if (c >= 0)

-               Ungetc(c, iob);
+               Ungetc(c, s);

        }
        *bufsz = *buf = 0;
        }
        *bufsz = *buf = 0;

-       return FILEEOF;
+       leave_getfld (s);
+       return s->state = FILEEOF;

     }
 
     }
 

-    switch (state) {
-       case FLDEOF:
-       case BODYEOF:
+    switch (s->state) {

        case FLD:
            if (c == '\n' || c == '-') {
                /* we hit the header/body separator */
        case FLD:
            if (c == '\n' || c == '-') {
                /* we hit the header/body separator */

-               while (c != '\n' && (c = Getc(iob)) >= 0) {
-                   ++bytes_read;
-               }
+               while (c != '\n' && (c = Getc(s)) >= 0) continue;

 
 

-               if (c < 0 || (c = Getc(iob)) < 0 || eom (c, iob)) {
-                   if (! eom_action) {
+               if (c < 0 || (c = Getc(s)) < 0 || eom (c, s)) {
+                   if (! s->eom_action) {

                        /* flush null messages */
                        /* flush null messages */

-                       while ((c = Getc(iob)) >= 0 && eom (c, iob))
+                       while ((c = Getc(s)) >= 0 && eom (c, s))

                            ;
                        if (c >= 0)
                            ;
                        if (c >= 0)

-                           Ungetc(c, iob);
+                           Ungetc(c, s);

                    }
                    *bufsz = *buf = 0;
                    }
                    *bufsz = *buf = 0;

-                   return FILEEOF;
+                   leave_getfld (s);
+                   return s->state = FILEEOF;

                }
                }

-               state = BODY;
+               s->state = BODY;

                goto body;
            }
            /*
                goto body;
            }
            /*


@@ -363,166 +541,128 @@ m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
             * comes first.
             */
            cp = name;
             * comes first.
             */
            cp = name;

-           i = NAMESZ - 1;
-           for (;;) {
-               /* Store current position, ungetting the last character. */
-               bp = sp = (unsigned char *) m.readpos - 1;
-               j = (cnt = m.end - m.readpos + 1) < i ? cnt : i;
-               while (--j >= 0 && (c = *bp++) != ':' && c != '\n') {
-                   *cp++ = c;
-                   ++bytes_read;
-               }
+           max = NAMESZ - 1;
+           /* Get the field name.  The first time through the loop,
+              this copies out the first character, which was loaded
+              into c prior to loop entry.  Initialize n to 1 to
+              account for that. */
+           for (n = 1;
+                c != ':'  &&  c != '\n'  &&  c != EOF  &&  n < max;
+                ++n, c = Getc (s)) {
+               *cp++ = c;
+           }

 
 

-               j = bp - sp;
-               if ((cnt -= j) <= 0) {
-                   /* Next to force refill of the buffer here. */
-                   m.readpos = m.end;
-                   if (Getc (iob) == EOF) {
-                       *bufsz = *cp = *buf = 0;
-                       advise (NULL, "eof encountered in field \"%s\"", name);
-                       return FMTERR;
-                   }
-               } else {
-                   /* Restore the current offset. */
-                   /* j was set to be less than or equal to the number of
-                      bytes available, so we can't overrun the end of the
-                      message buffer. */
-                   m.readpos = bp + 1;
+           /* Check for next character, which is either the space after
+              the ':' or the first folded whitespace. */
+           {
+               int next_char;
+               if (c == EOF  ||  (next_char = Peek (s)) == EOF) {
+                   *bufsz = *cp = *buf = 0;
+                   advise (NULL, "eof encountered in field \"%s\"", name);
+                   leave_getfld (s);
+                   return s->state = FMTERR;

                }
                }

-               if (c == ':')
-                   break;
+           }

 
 

-               /*
-                * something went wrong.  possibilities are:
-                *  . hit a newline (error)
-                *  . got more than namesz chars. (error)
-                *  . hit the end of the buffer. (loop)
-                */
-               if (c == '\n') {
-                   /* We hit the end of the line without seeing ':' to
-                    * terminate the field name.  This is usually (always?)
-                    * spam.  But, blowing up is lame, especially when
-                    * scan(1)ing a folder with such messages.  Pretend such
-                    * lines are the first of the body (at least mutt also
-                    * handles it this way). */
-
-                   /* See if buf can hold this line, since we were assuming
-                    * we had a buffer of NAMESZ, not bufsz. */
-                   /* + 1 for the newline */
-                   if (*bufsz < j + 1) {
-                       /* No, it can't.  Oh well, guess we'll blow up. */
-                       *bufsz = *cp = *buf = 0;
-                       advise (NULL, "eol encountered in field \"%s\"", name);
-                       state = FMTERR;
-                       goto finish;
-                   }
-                   memcpy (buf, name, j - 1);
-                   buf[j - 1] = '\n';
-                   buf[j] = '\0';
-                   /* mhparse.c:get_content wants to find the position of the
-                    * body start, but it thinks there's a blank line between
-                    * the header and the body (naturally!), so seek back so
-                    * that things line up even though we don't have that
-                    * blank line in this case.  Simpler parsers (e.g. mhl)
-                    * get extra newlines, but that should be harmless enough,
-                    * right?  This is a corrupt message anyway. */
-                   /* emulates:  fseek (iob, ftell (iob) -2), SEEK_SET) */
-                   m.readpos -= 2;
-                   *bufsz = bytes_read;
-                   return BODY;
-               }
-               if ((i -= j) <= 0) {
+           /* If c isn't ':' here, something went wrong.  Possibilities are:
+            *  . hit a newline (error)
+            *  . got more than namesz chars. (error)
+            */
+           if (c == ':') {
+               /* Finished header name, fall through to FLDPLUS below. */
+           } else if (c == '\n') {
+               /* We hit the end of the line without seeing ':' to
+                * terminate the field name.  This is usually (always?)
+                * spam.  But, blowing up is lame, especially when
+                * scan(1)ing a folder with such messages.  Pretend such
+                * lines are the first of the body (at least mutt also
+                * handles it this way). */
+
+               /* See if buf can hold this line, since we were assuming
+                * we had a buffer of NAMESZ, not bufsz. */
+               /* + 1 for the newline */
+               if (*bufsz < n + 1) {
+                   /* No, it can't.  Oh well, guess we'll blow up. */

                    *bufsz = *cp = *buf = 0;
                    *bufsz = *cp = *buf = 0;

-                   advise (NULL, "field name \"%s\" exceeds %d bytes", name, NAMESZ - 2);
-                   state = LENERR;
-                   goto finish;
+                   advise (NULL, "eol encountered in field \"%s\"", name);
+                   s->state = FMTERR;
+                   break;

                }
                }

+               memcpy (buf, name, n - 1);
+               buf[n - 1] = '\n';
+               buf[n] = '\0';
+               /* The last character read was '\n'.  s->bytes_read
+                  (and n) include that, but it was not put into the
+                  name array in the for loop above.  So subtract 1. */
+               *bufsz = --s->bytes_read;  /* == n - 1 */
+               leave_getfld (s);
+               return s->state = BODY;
+           } else if (max <= n) {
+               /* By design, the loop above discards the last character
+                   it had read.  It's in c, use it. */
+               *cp++ = c;
+               *bufsz = *cp = *buf = 0;
+               advise (NULL, "field name \"%s\" exceeds %d bytes", name,
+                       NAMESZ - 2);
+               s->state = LENERR;
+               break;

            }
 
            }
 

-           while (isspace (*--cp) && cp >= name) {
-               --bytes_read;
-           }
+           /* Trim any trailing spaces from the end of name. */
+           while (isspace ((unsigned char) *--cp) && cp >= name) continue;

            *++cp = 0;
            *++cp = 0;

+           /* readpos points to the first character of the field body. */

            /* fall through */
 
            /* fall through */
 

-       case FLDPLUS:
+       case FLDPLUS: {

            /*
            /*

-            * get (more of) the text of a field.  take
+            * get (more of) the text of a field.  Take

             * characters up to the end of this field (newline
             * followed by non-blank) or bufsz-1 characters.
             */
             * characters up to the end of this field (newline
             * followed by non-blank) or bufsz-1 characters.
             */

-           cp = buf; i = *bufsz-1;
-           for (;;) {
-               /* Set, and save, the current position, and update cnt. */
-               cnt = m.end - m.readpos;
-               bp = --m.readpos;
-               c = cnt < i ? cnt : i;
-               while ((ep = locc( c, bp, '\n' ))) {
-                   /*
-                    * if we hit the end of this field, return.
-                    */
-                   if ((j = *++ep) != ' ' && j != '\t') {
-                       /* Save the text and update the current position. */
-                       j = ep - m.readpos;
-                       memcpy (cp, m.readpos, j);
-                       /* c is less than or equal to the number of bytes
-                          remaining in the read buffer, so will not overrun. */
-                       m.readpos = ep;
-                       cp += j;
-                       state = FLD;
-                       goto finish;
-                   }
-                   c -= ep - bp;
-                   bp = ep;
+           int finished;
+
+           cp = buf;
+           max = *bufsz-1;
+           n = 0;
+           for (finished = 0; ! finished; ) {
+               while (c != '\n'  &&  c != EOF  &&  n++ < max) {
+                   *cp++ = c = Getc (s);

                }
                }

-               /*
-                * end of input or dest buffer - copy what we've found.
-                */
-               c += bp - m.readpos;
-               for (k = 0; k < c; ++k, --i) {
-                   *cp++ = Getc (iob);
-               }
-               if (i <= 0) {
+
+               if (c != EOF) c = Peek (s);
+               if (max < n) {

                    /* the dest buffer is full */
                    /* the dest buffer is full */

-                   state = FLDPLUS;
-                   break;
-               }
-               /*
-                * There's one character left in the input buffer.
-                * Copy it & fill the buffer (that fill used to be
-                * explicit, but now Getc() does it).  If the last char
-                * was a newline and the next char is not whitespace,
-                * this is the end of the field.  Otherwise loop.
-                */
-               --i;
-               *cp++ = j = Getc (iob);
-               c = Getc (iob);
-                if (c == EOF ||
-                 ((j == '\0' || j == '\n') && c != ' ' && c != '\t')) {
-                   if (c != EOF) {
-                       /* Put the character back for the next call. */
-                       --m.readpos;
-                   }
-                   state = FLD;
-                   break;
+                   s->state = FLDPLUS;
+                   finished = 1;
+               } else if (c != ' '  &&  c != '\t') {
+                   /* The next character is not folded whitespace, so
+                      prepare to move on to the next field.  It's OK
+                      if c is EOF, it will be handled on the next
+                      call to m_getfld (). */
+                   s->state = FLD;
+                   finished = 1;
+               } else {
+                   /* Folded header field, continues on the next line. */

                }
            }
                }
            }

+           *bufsz = s->bytes_read;

            break;
            break;

+        }

 
 

-       case BODY:

        body:
        body:

+       case BODY: {

            /*
             * get the message body up to bufsz characters or the
            /*
             * get the message body up to bufsz characters or the

-            * end of the message.  Sleazy hack: if bufsz is negative
-            * we assume that we were called to copy directly into
-            * the output buffer and we don't add an eos.
+            * end of the message.

             */
             */

-           i = (*bufsz < 0) ? -*bufsz : *bufsz-1;
-           /* Back up and store the current position and update cnt. */
-           bp = --m.readpos;
-           cnt = m.end - m.readpos;
-           c = cnt < i ? cnt : i;
-           if (msg_style != MS_DEFAULT && c > 1) {
+           char *bp;
+
+           max = *bufsz-1;
+           /* Back up and store the current position. */
+           bp = --s->readpos;
+           c = s->end - s->readpos < max  ?  s->end - s->readpos  :  max;
+           if (s->msg_style != MS_DEFAULT && c > 1) {

                /*
                 * packed maildrop - only take up to the (possible)
                 * start of the next message.  This "matchc" should
                /*
                 * packed maildrop - only take up to the (possible)
                 * start of the next message.  This "matchc" should


@@ -535,7 +675,9 @@ m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
                 * algorithms vs. brute force.)  Since I (currently)
                 * run MH on a vax, we use the matchc instruction. --vj
                 */
                 * algorithms vs. brute force.)  Since I (currently)
                 * run MH on a vax, we use the matchc instruction. --vj
                 */

-               if ((ep = matchc( fdelimlen, fdelim, c, bp )))
+               char *ep;
+
+               if ((ep = matchc( s->fdelimlen, s->fdelim, c, bp )))

                    c = ep - bp + 1;
                else {
                    /*
                    c = ep - bp + 1;
                else {
                    /*


@@ -551,8 +693,10 @@ m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
                     * ends with one of the characters in the pattern
                     * (excluding the first and last), we do only one test.
                     */
                     * ends with one of the characters in the pattern
                     * (excluding the first and last), we do only one test.
                     */

+                   char *sp;
+

                    ep = bp + c - 1;
                    ep = bp + c - 1;

-                   if ((sp = pat_map[*ep])) {
+                   if ((sp = s->pat_map[(unsigned char) *ep])) {

                        do {
                            /* This if() is true unless (a) the buffer is too
                             * small to contain this delimiter prefix, or
                        do {
                            /* This if() is true unless (a) the buffer is too
                             * small to contain this delimiter prefix, or


@@ -564,7 +708,7 @@ m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
                             * should have found it.  Thus it's not a delim
                             * and we know we won't get a match.
                             */
                             * should have found it.  Thus it's not a delim
                             * and we know we won't get a match.
                             */

-                           if (((sp - fdelim) + 2) <= c) {
+                           if (((sp - s->fdelim) + 2) <= c) {

                                cp = sp;
                                /* Unfortunately although fdelim has a preceding NUL
                                 * we can't use this as a sentinel in case the buffer
                                cp = sp;
                                /* Unfortunately although fdelim has a preceding NUL
                                 * we can't use this as a sentinel in case the buffer


@@ -572,9 +716,9 @@ m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
                                 * would cause us to run off the front of fdelim).
                                 */
                                while (*--ep == *--cp)
                                 * would cause us to run off the front of fdelim).
                                 */
                                while (*--ep == *--cp)

-                                   if (cp < fdelim)
+                                   if (cp < s->fdelim)

                                        break;
                                        break;

-                               if (cp < fdelim) {
+                               if (cp < s->fdelim) {

                                    /* we matched the entire delim prefix,
                                     * so only take the buffer up to there.
                                     * we know ep >= bp -- check above prevents underrun
                                    /* we matched the entire delim prefix,
                                     * so only take the buffer up to there.
                                     * we know ep >= bp -- check above prevents underrun


@@ -585,7 +729,7 @@ m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
                            }
                            /* try matching one less char of delim string */
                            ep = bp + c - 1;
                            }
                            /* try matching one less char of delim string */
                            ep = bp + c - 1;

-                       } while (--sp > fdelim);
+                       } while (--sp > s->fdelim);

                    }
                }
            }
                    }
                }
            }


@@ -593,34 +737,39 @@ m_getfld (int state, unsigned char name[NAMESZ], unsigned char *buf,
            /* Advance the current position to reflect the copy out.
               c is less than or equal to the number of bytes remaining
               in the read buffer, so will not overrun it. */
            /* Advance the current position to reflect the copy out.
               c is less than or equal to the number of bytes remaining
               in the read buffer, so will not overrun it. */

-           m.readpos += c;
-           if (*bufsz < 0) {
-               *bufsz = c + bytes_read + 1;
-               return (state);
-           }
+           s->readpos += c;

            cp = buf + c;
            cp = buf + c;

+           /* Subtract 1 from c because the first character was read by
+              Getc(), and therefore already accounted for in s->bytes_read. */
+           s->bytes_read += c - 1;
+           *bufsz = s->bytes_read;

            break;
            break;

+        }

 
        default:
 
        default:

-           adios (NULL, "m_getfld() called with bogus state of %d", state);
+           adios (NULL, "m_getfld() called with bogus state of %d", s->state);

     }
     }

-finish:
+

     *cp = 0;
     *cp = 0;

-    *bufsz = cp - buf + bytes_read + 1;
-    return (state);
+    leave_getfld (s);
+
+    return s->state;

 }
 
 
 void
 }
 
 
 void

-m_unknown(FILE *iob)
+m_unknown(m_getfld_state_t *gstate, FILE *iob)

 {
 {

+    m_getfld_state_t s;

     register int c;
     char text[MAX_DELIMITER_SIZE];
     register int c;
     char text[MAX_DELIMITER_SIZE];

+    char from[] = "From ";

     register char *cp;
     register char *delimstr;
     register char *cp;
     register char *delimstr;

-    size_t bytes_read = 0;
+    unsigned int i;

 
 

-    setup_buffer (iob, &m);
+    enter_getfld (gstate, iob);
+    s = *gstate;

 
 /*
  * Figure out what the message delimitter string is for this
 
 /*
  * Figure out what the message delimitter string is for this


@@ -635,44 +784,35 @@ m_unknown(FILE *iob)
  * specified when nmh was built (or from the mts.conf file).
  */
 
  * specified when nmh was built (or from the mts.conf file).
  */
 

-    msg_style = MS_UNKNOWN;
+    s->msg_style = MS_UNKNOWN;

 
 

-    for (c = 0, cp = text; c < 5; ++c, ++cp) {
-       ++bytes_read;
-       if ((*cp = Getc (iob)) == EOF) {
+    for (i = 0, cp = text; i < sizeof text; ++i, ++cp) {
+       if ((*cp = Getc (s)) == EOF) {

            break;
        }
     }
 
            break;
        }
     }
 

-    if (c == 5  &&  strncmp (text, "From ", 5) == 0) {
-       msg_style = MS_MBOX;
+    if (i == sizeof from-1  &&  strncmp (text, "From ", sizeof from-1) == 0) {
+       s->msg_style = MS_MBOX;

        delimstr = "\nFrom ";
        delimstr = "\nFrom ";

-       while (++bytes_read, (c = Getc (iob)) != '\n' && c >= 0)
-           ;
-       /* m_unknown is only called on maildrop files, and they are only
-          read using m_getfld ().  The caller musn't try to read from
-          the stream directly because the file position indicator was
-          not advanced based on bytes_read, but instead on whatever
-          was read into the message buffer. */
+       while ((c = Getc (s)) != '\n' && c >= 0) continue;

     } else {
        /* not a Unix style maildrop */
     } else {
        /* not a Unix style maildrop */

-       m.readpos -= bytes_read; /* fseek (iob, pos, SEEK_SET), but relative. */
-       if (mmdlm2 == NULL || *mmdlm2 == 0)
-           mmdlm2 = "\001\001\001\001\n";
+       s->readpos -= s->bytes_read;

        delimstr = mmdlm2;
        delimstr = mmdlm2;

-       msg_style = MS_MMDF;
+       s->msg_style = MS_MMDF;

     }
     c = strlen (delimstr);
     }
     c = strlen (delimstr);

-    fdelim = (unsigned char *) mh_xmalloc((size_t) (c + 3));
-    *fdelim++ = '\0';
-    *fdelim = '\n';
-    msg_delim = (char *)fdelim+1;
-    edelim = (unsigned char *)msg_delim+1;
-    fdelimlen = c + 1;
-    edelimlen = c - 1; /* == strlen (delimstr) */
-    strcpy (msg_delim, delimstr);
-    delimend = (unsigned char *)msg_delim + edelimlen;
-    if (edelimlen <= 1)
+    s->fdelim = mh_xmalloc (c + 3);
+    *s->fdelim++ = '\0';
+    *s->fdelim = '\n';
+    s->msg_delim = s->fdelim+1;
+    s->edelim = s->msg_delim+1;
+    s->fdelimlen = c + 1;
+    s->edelimlen = c - 1; /* == strlen (delimstr) */
+    strcpy (s->msg_delim, delimstr);
+    s->delimend = s->msg_delim + s->edelimlen;
+    if (s->edelimlen <= 1)

        adios (NULL, "maildrop delimiter must be at least 2 bytes");
     /*
      * build a Boyer-Moore end-position map for the matcher in m_getfld.
        adios (NULL, "maildrop delimiter must be at least 2 bytes");
     /*
      * build a Boyer-Moore end-position map for the matcher in m_getfld.


@@ -680,34 +820,36 @@ m_unknown(FILE *iob)
      * separator) or the last char (since the matchc would have found it
      * if it was a real delim).
      */
      * separator) or the last char (since the matchc would have found it
      * if it was a real delim).
      */

-    pat_map = (unsigned char **) calloc (256, sizeof(unsigned char *));
+    s->pat_map = (char **) calloc (256, sizeof(char *));

 
 

-    for (cp = (char *) fdelim + 1; cp < (char *) delimend; cp++ )
-       pat_map[(unsigned char)*cp] = (unsigned char *) cp;
+    for (cp = s->fdelim + 1; cp < s->delimend; cp++ )
+       s->pat_map[(unsigned char)*cp] = cp;

 
 

-    if (msg_style == MS_MMDF) {
+    if (s->msg_style == MS_MMDF) {

        /* flush extra msg hdrs */
        /* flush extra msg hdrs */

-       while ((c = Getc(iob)) >= 0 && eom (c, iob))
+       while ((c = Getc(s)) >= 0 && eom (c, s))

            ;
        if (c >= 0)
            ;
        if (c >= 0)

-           Ungetc(c, iob);
+           Ungetc(c, s);

     }
     }

+
+    leave_getfld (s);

 }
 
 
 void
 }
 
 
 void

-m_eomsbr (int (*action)(int))
+m_eomsbr (m_getfld_state_t s, int (*action)(int))

 {
 {

-    if ((eom_action = action)) {
-       msg_style = MS_MSH;
-       *msg_delim = 0;
-       fdelimlen = 1;
-       delimend = fdelim;
+    if ((s->eom_action = action)) {
+       s->msg_style = MS_MSH;
+       *s->msg_delim = 0;
+       s->fdelimlen = 1;
+       s->delimend = s->fdelim;

     } else {
     } else {

-       msg_style = MS_MMDF;
-       msg_delim = (char *)fdelim + 1;
-       fdelimlen = strlen((char *)fdelim);
-       delimend = (unsigned char *)(msg_delim + edelimlen);
+       s->msg_style = MS_MMDF;
+       s->msg_delim = s->fdelim + 1;
+       s->fdelimlen = strlen (s->fdelim);
+       s->delimend = s->msg_delim + s->edelimlen;

     }
 }
 
     }
 }
 


@@ -717,22 +859,21 @@ m_eomsbr (int (*action)(int))
  */
 
 static int
  */
 
 static int

-m_Eom (int c, FILE *iob)
+m_Eom (m_getfld_state_t s, int c)

 {
     register int i;
 {
     register int i;

-    size_t bytes_read = 0;

     char text[MAX_DELIMITER_SIZE];
     char *cp;
 
     char text[MAX_DELIMITER_SIZE];
     char *cp;
 

-    for (i = 0, cp = text; i < edelimlen; ++i, ++cp) {
-       ++bytes_read;
-       if ((*cp = Getc (iob)) == EOF) {
+    for (i = 0, cp = text; i < s->edelimlen; ++i, ++cp) {
+       if ((*cp = Getc (s)) == EOF) {

            break;
        }
     }
 
            break;
        }
     }
 

-    if (i != edelimlen  ||  strncmp (text, (char *)edelim, edelimlen)) {
-       if (i == 0 && msg_style == MS_MBOX)
+    if (i != s->edelimlen  ||
+        strncmp (text, (char *)s->edelim, s->edelimlen)) {
+       if (i == 0 && s->msg_style == MS_MBOX)

            /* the final newline in the (brain damaged) unix-format
             * maildrop is part of the delimitter - delete it.
             */
            /* the final newline in the (brain damaged) unix-format
             * maildrop is part of the delimitter - delete it.
             */


@@ -741,12 +882,12 @@ m_Eom (int c, FILE *iob)
        /* Did not find delimiter, so restore the read position.
           Note that on input, a character had already been read
           with Getc().  It will be unget by m_getfld () on return. */
        /* Did not find delimiter, so restore the read position.
           Note that on input, a character had already been read
           with Getc().  It will be unget by m_getfld () on return. */

-       m.readpos -= bytes_read;
+       s->readpos -= s->bytes_read - 1;

        return 0;
     }
 
        return 0;
     }
 

-    if (msg_style == MS_MBOX) {
-       while ((c = Getc (iob)) != '\n')
+    if (s->msg_style == MS_MBOX) {
+       while ((c = Getc (s)) != '\n')

            if (c < 0)
                break;
     }
            if (c < 0)
                break;
     }


@@ -755,7 +896,7 @@ m_Eom (int c, FILE *iob)
 }
 
 
 }
 
 

-static unsigned char *
+static char *

 matchc(int patln, char *pat, int strln, char *str)
 {
        register char *es = str + strln - patln;
 matchc(int patln, char *pat, int strln, char *str)
 {
        register char *es = str + strln - patln;


@@ -774,20 +915,6 @@ matchc(int patln, char *pat, int strln, char *str)
                while (pp < ep && *sp++ == *pp)
                        pp++;
                if (pp >= ep)
                while (pp < ep && *sp++ == *pp)
                        pp++;
                if (pp >= ep)

-                       return ((unsigned char *)--str);
+                       return --str;

        }
 }
        }
 }

-
-
-/*
- * Locate character "term" in the next "cnt" characters of "src".
- * If found, return its address, otherwise return 0.
- */
-
-static unsigned char *
-locc(int cnt, unsigned char *src, unsigned char term)
-{
-    while (*src++ != term && --cnt > 0);
-
-    return (cnt > 0 ? --src : (unsigned char *)0);
-}