+
+ /*
+ * We're trying to delete a header field (annotation )if the
+ * delete flag is not -2 or less. A value greater than zero
+ * means that we're deleting the nth header field that matches
+ * the field (component) name. A value of zero means that
+ * we're deleting the first field in which both the field name
+ * matches the component name and the field body matches the text.
+ * The text is matched in its entirety if it begins with a slash;
+ * otherwise the text is matched against whatever portion of the
+ * field body follows the last slash. This allows matching of
+ * both absolute and relative path names. This is because this
+ * functionality was added to support attachments. It might be
+ * worth having a separate flag to indicate path name matching
+ * to make it more general. A value of -1 means to delete all
+ * matching fields.
+ */
+
+ if (delete >= -1) {
+ /*
+ * Get the length of the field name since we use it often.
+ */
+
+ length = strlen(comp);
+
+ /*
+ * Initialize the field counter. This is only used if
+ * we're deleting by number.
+ */
+
+ count = 0;
+
+ /*
+ * Copy lines from the input file to the temporary file
+ * until we either find the one that we're looking
+ * for (which we don't copy) or we reach the end of
+ * the headers. Both a blank line and a line beginning
+ * with a - terminate the headers so that we can handle
+ * both drafts and RFC-2822 format messages.
+ */
+
+ do {
+ /*
+ * Get a line from the input file, growing the
+ * field buffer as needed. We do this so that
+ * we can fit an entire line in the buffer making
+ * it easy to do a string comparison on both the
+ * field name and the field body which might be
+ * a long path name.
+ */
+
+ for (n = 0, cp = field; (c = getc(fp)) != EOF; *cp++ = c) {
+ if (c == '\n' && (c = getc(fp)) != ' ' && c != '\t') {
+ (void)ungetc(c, fp);
+ c = '\n';
+ break;
+ }
+
+ if (++n >= field_size - 1) {
+ field = (char *) mh_xrealloc((void *)field, field_size *= 2);
+
+ cp = field + n - 1;
+ }
+ }
+
+ /*
+ * NUL-terminate the field..
+ */
+
+ *cp = '\0';
+
+ /*
+ * Check for a match on the field name. We delete
+ * the line by not copying it to the temporary
+ * file if
+ *
+ * o The delete flag is 0, meaning that we're
+ * going to delete the first matching
+ * field, and the text is NULL meaning that
+ * we don't care about the field body.
+ *
+ * o The delete flag is 0, meaning that we're
+ * going to delete the first matching
+ * field, and the text begins with a / meaning
+ * that we're looking for a full path name,
+ * and the text matches the field body.
+ *
+ * o The delete flag is 0, meaning that we're
+ * going to delete the first matching
+ * field, the text does not begin with a /
+ * meaning that we're looking for the last
+ * path name component, and the last path
+ * name component matches the text.
+ *
+ * o The delete flag is positive meaning that
+ * we're going to delete the nth field
+ * with a matching field name, and this is
+ * the nth matching field name.
+ *
+ * o The delete flag is -1 meaning that we're
+ * going to delete all fields with a
+ * matching field name.
+ */
+
+ if (strncasecmp(field, comp, length) == 0 && field[length] == ':') {
+ if (delete == 0) {
+ if (text == (char *)0)
+ break;
+
+ for (cp = field + length + 1; *cp == ' ' || *cp == '\t'; cp++)
+ ;
+
+ if (*text == '/') {
+ if (strcmp(cp, text) == 0)
+ break;
+ }
+ else {
+ if ((sp = strrchr(cp, '/')) != (char *)0)
+ cp = sp + 1;
+
+ if (strcmp(cp, text) == 0)
+ break;
+ }
+ }
+
+ else if (delete == -1)
+ continue;
+
+ else if (++count == delete)
+ break;
+ }
+
+ /*
+ * This line wasn't a match so copy it to the
+ * temporary file.
+ */
+
+ if ((n = fputs(field, tmp)) == EOF || (c == '\n' && fputc('\n', tmp) == EOF))
+ adios(NULL, "unable to write temporary file.");
+
+ } while (*field != '\0' && *field != '-');
+
+ /*
+ * Get rid of the field buffer because we're done with it.
+ */
+
+ free((void *)field);
+ }
+
+ else {
+ /*
+ * Find the end of the headers before adding the
+ * annotations if we're appending instead of the default
+ * prepending. A special check for no headers is needed
+ * if appending.
+ */
+
+ if (append) {
+ /*
+ * Copy lines from the input file to the temporary
+ * file until we reach the end of the headers.
+ */
+
+ if ((c = getc(fp)) == '\n')
+ rewind(fp);
+
+ else {
+ (void)putc(c, tmp);
+
+ while ((c = getc(fp)) != EOF) {
+ (void)putc(c, tmp);
+
+ if (c == '\n') {
+ (void)ungetc(c = getc(fp), fp);
+
+ if (c == '\n' || c == '-')
+ break;
+ }
+ }
+ }
+ }
+
+ if (datesw)
+ fprintf (tmp, "%s: %s\n", comp, dtimenow (0));
+ if ((cp = text)) {
+ do {
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ sp = cp;
+ while (*cp && *cp++ != '\n')
+ continue;
+ if (cp - sp)
+ fprintf (tmp, "%s: %*.*s", comp, (int)(cp - sp), (int)(cp - sp), sp);
+ } while (*cp);
+ if (cp[-1] != '\n' && cp != text)
+ putc ('\n', tmp);
+ }
+ }
+
+ fflush (tmp);
+
+ /*
+ * We've been messing with the input file position. Move the
+ * input file descriptor to the current place in the file
+ * because the stock data copying routine uses the descriptor,
+ * not the pointer.
+ */
+
+ if (append || delete >= -1) {
+ if (lseek(fd, (off_t)ftell(fp), SEEK_SET) == (off_t)-1)
+ adios(NULL, "can't seek.");