}
/*
- * %read-line uses a port's fgets method for fast line i/o.
- * For %read-line to replace read-line, it will have to take these options:
- *
- * %READ-LINE [PORT [HANDLE-DELIM]]
- *
- * HANDLE-DELIM instructs %READ-LINE how to handle line delimiter
- * characters, and must be one of the symbols `trim', `concat',
- * `split', `peek'. If it is `trim' (the default), the line delimiter
- * is read from the port and discarded. If it is `concat', the
- * delimiter is read from the port and appended to the string. If it
- * is `split', the delimiter is read from the port, and %READ-LINE
- * returns a pair consisting of the line read and the delimiter
- * character. If it is `peek', the delimiter is not read from the
- * port at all.
- *
- * Complicating all this, boot-9's READ-LINE function uses the value
- * of SCM-LINE-INCREMENTORS to delimit lines. That means that Guile
- * programmers could potentially read records delimited by arbitrary
- * characters by changing the value of SCM-LINE-INCREMENTORS and then
- * calling READ-LINE. If we are to take advantage of fgets(3), we
- * can't afford this luxury. %READ-LINE will be limited to processing
- * newline-delimited records.
+ * %read-line uses a port's fgets method for fast line i/o. It
+ * truncates any terminating newline from its input, and returns
+ * a cons of the string read and its terminating character. Doing
+ * so makes it easy to implement the hairy `read-line' options
+ * efficiently in Scheme.
*/
SCM_PROC (s_read_line, "%read-line", 0, 1, 0, scm_read_line);
SCM port;
{
char *s;
- SCM line;
+ int slen;
+ SCM line, term;
if (SCM_UNBNDP (port))
port = scm_cur_inp;
port, SCM_ARG1, s_read_line);
}
- s = scm_do_read_line (port);
+ s = scm_do_read_line (port, &slen);
+
if (s == NULL)
- line = SCM_EOF_VAL;
+ term = line = SCM_EOF_VAL;
else
{
- line = scm_makfrom0str (s);
+ if (s[slen-1] == '\n')
+ {
+ term = SCM_MAKICHR ('\n');
+ line = scm_makfromstr (s, slen-1, 0);
+ }
+ else
+ {
+ /* Fix: we should check for eof on the port before assuming this. */
+ term = SCM_EOF_VAL;
+ line = scm_makfromstr (s, slen, 0);
+ }
free (s);
}
- return line;
+
+ return scm_cons (line, term);
}
SCM_PROC (s_write_line, "write-line", 1, 1, 0, scm_write_line);