X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/45a84738dfab22fecb11a493fac946c23217b6eb..665dfc96:/sbr/m_getfld.c?ds=sidebyside

diff --git a/sbr/m_getfld.c b/sbr/m_getfld.c
index 135be1db..0f068031 100644
--- a/sbr/m_getfld.c
+++ b/sbr/m_getfld.c
@@ -1,6 +1,4 @@
-
-/*
- * m_getfld.c -- read/parse a message
+/* m_getfld.c -- read/parse a message
  *
  * This code is Copyright (c) 2002, by the authors of nmh.  See the
  * COPYRIGHT file in the root directory of the nmh distribution for
@@ -159,7 +157,7 @@
    names are typically short (~8 char) and the loop that extracts them
    might terminate on a colon, newline or max width.  I considered
    using a Vax "scanc" to locate the end of the field followed by a
-   "bcopy" but the routine call overhead on a Vax is too large for this
+   "memmove" but the routine call overhead on a Vax is too large for this
    to work on short names.  If Berkeley ever makes "inline" part of the
    C optimiser (so things like "scanc" turn into inline instructions) a
    change here would be worthwhile.
@@ -175,7 +173,7 @@
    so message bodies average at least a few hundred characters.
    Assuming your system uses reasonably sized stdio buffers (1K or
    more), this routine should be able to remove the body in large
-   (>500 byte) chunks.  The makes the cost of a call to "bcopy"
+   (>500 byte) chunks.  The makes the cost of a call to "memmove"
    small but there is a premium on checking for the eom in packed
    maildrops.  The eom pattern is always a simple string so we can
    construct an efficient pattern matcher for it (e.g., a Vax "matchc"
@@ -202,9 +200,7 @@
 /*
  * static prototypes
  */
-struct m_getfld_state;
 static int m_Eom (m_getfld_state_t);
-static char *matchc(int, char *, int, char *);
 
 #define eom(c,s)	(s->msg_style != MS_DEFAULT && \
 			 ((c) == *s->msg_delim && m_Eom(s)))
@@ -268,7 +264,8 @@ 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));
+    NEW(s);
+    *gstate = s;
     s->readpos = s->end = s->msg_buf;
     s->bytes_read = s->total_bytes_read = 0;
     s->last_caller_pos = s->last_internal_pos = 0;
@@ -432,7 +429,8 @@ read_more (m_getfld_state_t s) {
     ssize_t retain = s->edelimlen;
     size_t num_read;
 
-    if (retain < s->end - s->readpos) retain = s->end - s->readpos;
+    if (retain < s->end - s->readpos)
+        retain = s->end - s->readpos;
     assert (retain <= s->readpos - s->msg_buf);
 
     /* Move what we want to retain at end of the buffer to the beginning. */
@@ -462,19 +460,17 @@ static int
 Peek (m_getfld_state_t s) {
     if (s->end - s->readpos < 1  &&  read_more (s) == 0) {
         return EOF;
-    } else {
-        return s->readpos < s->end  ?  (unsigned char) *s->readpos  :  EOF;
     }
+    return s->readpos < s->end  ?  (unsigned char) *s->readpos  :  EOF;
 }
 
 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;
     }
+    --s->bytes_read;
+    return *--s->readpos = (unsigned char) c;
 }
 
 
@@ -483,8 +479,8 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
           FILE *iob)
 {
     m_getfld_state_t s;
-    register char *cp;
-    register int max, n, c;
+    char *cp;
+    int max, n, c;
 
     enter_getfld (gstate, iob);
     s = *gstate;
@@ -549,7 +545,7 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
 		int next_char;
 		if (c == EOF  ||  (next_char = Peek (s)) == EOF) {
 		    *bufsz = *cp = *buf = 0;
-		    advise (NULL, "eof encountered in field \"%s\"", name);
+		    inform("eof encountered in field \"%s\"", name);
 		    leave_getfld (s);
 		    return s->state = FMTERR;
 		}
@@ -575,25 +571,29 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
 		if (*bufsz < n + 1) {
 		    /* No, it can't.  Oh well, guess we'll blow up. */
 		    *bufsz = *cp = *buf = 0;
-		    advise (NULL, "eol encountered in field \"%s\"", name);
+		    inform("eol encountered in field \"%s\"", name);
 		    s->state = FMTERR;
 		    break;
 		}
 		memcpy (buf, name, n - 1);
 		buf[n - 1] = '\n';
 		buf[n] = '\0';
+                /* Indicate this wasn't a header field using a character
+                   that can't appear in a header field. */
+                name[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) {
+	    }
+            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,
+		inform("field name \"%s\" exceeds %d bytes", name,
 			NAMESZ - 2);
 		s->state = LENERR;
 		break;
@@ -603,7 +603,7 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
 	    while (isspace ((unsigned char) *--cp) && cp >= name) continue;
 	    *++cp = 0;
 	    /* readpos points to the first character of the field body. */
-	    /* fall through */
+	    /* FALLTHRU */
 
 	case FLDPLUS: {
 	    /*
@@ -618,10 +618,12 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
 	    n = 0;
 	    for (finished = 0; ! finished; ) {
 		while (c != '\n'  &&  c != EOF  &&  n++ < max) {
-		    if ((c = Getc (s)) != EOF) { *cp++ = c; }
+		    if ((c = Getc (s)) != EOF)
+                        *cp++ = c;
 		}
 
-		if (c != EOF) c = Peek (s);
+		if (c != EOF)
+                    c = Peek (s);
 		if (max < n) {
 		    /* The dest buffer is full.  Need to back the read
 		       pointer up by one because when m_getfld() is
@@ -658,10 +660,11 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
 	     */
 	    char *bp;
 
+            name[0] = '\0';
 	    max = *bufsz-1;
 	    /* Back up and store the current position. */
 	    bp = --s->readpos;
-	    c = s->end - s->readpos < max  ?  s->end - s->readpos  :  max;
+            c = min(s->end - s->readpos, max);
 	    if (s->msg_style != MS_DEFAULT && c > 1) {
 		/*
 		 * packed maildrop - only take up to the (possible)
@@ -677,7 +680,7 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz,
 		 */
 		char *ep;
 
-		if ((ep = matchc( s->fdelimlen, s->fdelim, c, bp )))
+                if ((ep = memmem(bp, c, s->fdelim, s->fdelimlen)))
 		    c = ep - bp + 1;
 		else {
 		    /*
@@ -761,18 +764,18 @@ void
 m_unknown(m_getfld_state_t *gstate, FILE *iob)
 {
     m_getfld_state_t s;
-    register int c;
+    int c;
     char text[MAX_DELIMITER_SIZE];
     char from[] = "From ";
-    register char *cp;
-    register char *delimstr;
+    char *cp;
+    char *delimstr;
     unsigned int i;
 
     enter_getfld (gstate, iob);
     s = *gstate;
 
 /*
- * Figure out what the message delimitter string is for this
+ * Figure out what the message delimiter string is for this
  * maildrop.  (This used to be part of m_Eom but I didn't like
  * the idea of an "if" statement that could only succeed on the
  * first call to m_Eom getting executed on each call, i.e., at
@@ -790,9 +793,8 @@ m_unknown(m_getfld_state_t *gstate, FILE *iob)
 	if ((c = Getc (s)) == EOF) {
 	    *cp = '\0';
 	    break;
-	} else {
-	    *cp = c;
 	}
+        *cp = c;
     }
 
     if (i == sizeof from-1  &&  strncmp (text, "From ", sizeof from-1) == 0) {
@@ -807,18 +809,32 @@ m_unknown(m_getfld_state_t *gstate, FILE *iob)
 	delimstr = mmdlm2;
 	s->msg_style = MS_MMDF;
     }
+
     c = strlen (delimstr);
-    s->fdelim = mh_xmalloc (c + 3);
+    s->fdelim = mh_xmalloc (c + 3); /* \0, \n, delimstr, \0 */
     *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) */
+    s->msg_delim = s->fdelim+1;
     strcpy (s->msg_delim, delimstr);
+    s->edelim = s->msg_delim+1;
+    s->edelimlen = c - 1;
     s->delimend = s->msg_delim + s->edelimlen;
     if (s->edelimlen <= 1)
 	adios (NULL, "maildrop delimiter must be at least 2 bytes");
+
+    /* Now malloc'd memory at s->fdelim-1 referenced several times:
+     *
+     *     delimstr         "\nFrom "      "\001\001\001\001\n"
+     *     c                6              5
+     *     s->fdelim      \0"\n\nFrom "  \0"\n\001\001\001\001\n"
+     *     s->fdelimlen     6              5
+     *     s->msg_delim     "\nFrom "      "\001\001\001\001\n"
+     *     s->edelim        "From "        "\001\001\001\n"
+     *     s->edelimlen     5              4
+     *     s->delimend      " "            "\n"
+     */
+
     /*
      * build a Boyer-Moore end-position map for the matcher in m_getfld.
      * N.B. - we don't match just the first char (since it's the newline
@@ -849,7 +865,7 @@ m_unknown(m_getfld_state_t *gstate, FILE *iob)
 static int
 m_Eom (m_getfld_state_t s)
 {
-    register int i;
+    int i;
     char text[MAX_DELIMITER_SIZE];
     char *cp;
 
@@ -859,16 +875,15 @@ m_Eom (m_getfld_state_t s)
 	if ((c2 = Getc (s)) == EOF) {
 	    *cp = '\0';
 	    break;
-	} else {
-	    *cp = c2;
 	}
+        *cp = c2;
     }
 
     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.
+	     * maildrop is part of the delimiter - delete it.
 	     */
 	    return 1;
 
@@ -888,27 +903,3 @@ m_Eom (m_getfld_state_t s)
 
     return 1;
 }
-
-
-static char *
-matchc(int patln, char *pat, int strln, char *str)
-{
-	register char *es = str + strln - patln;
-	register char *sp;
-	register char *pp;
-	register char *ep = pat + patln;
-	register char pc = *pat++;
-
-	for(;;) {
-		while (pc != *str++)
-			if (str > es)
-				return 0;
-		if (str > es+1)
-			return 0;
-		sp = str; pp = pat;
-		while (pp < ep && *sp++ == *pp)
-			pp++;
-		if (pp >= ep)
-			return --str;
-	}
-}