Major reconstruction work for new design.
[fwd] / conf.h
diff --git a/conf.h b/conf.h
index e1713ee..1704587 100644 (file)
--- a/conf.h
+++ b/conf.h
@@ -1,10 +1,10 @@
 /* -*-c-*-
  *
- * $Id: conf.h,v 1.1 1999/07/01 08:56:23 mdw Exp $
+ * $Id: conf.h,v 1.2 1999/07/26 23:28:39 mdw Exp $
  *
  * Configuration parsing
  *
- * (c) 1999 Mark Wooding
+ * (c) 1999 Straylight/Edgeware
  */
 
 /*----- Licensing notice --------------------------------------------------* 
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: conf.h,v $
- * Revision 1.1  1999/07/01 08:56:23  mdw
- * Initial revision
+ * Revision 1.2  1999/07/26 23:28:39  mdw
+ * Major reconstruction work for new design.
+ *
+ * Revision 1.1.1.1  1999/07/01 08:56:23  mdw
+ * Initial revision.
  *
  */
 
 
 /*----- Header files ------------------------------------------------------*/
 
+#include <mLib/dstr.h>
+
 #ifndef SCAN_H
 #  include "scan.h"
 #endif
 
+/*----- Magic numbers -----------------------------------------------------*/
+
+#define CTOK_EOF (-1)
+#define CTOK_WORD 256
+
 /*----- Functions provided ------------------------------------------------*/
 
+/* --- @token@ --- *
+ *
+ * Arguments:  @scanner *sc@ = pointer to scanner definition
+ *
+ * Returns:    Type of token scanned.
+ *
+ * Use:                Reads the next token from the character scanner.
+ */
+
+extern int token(scanner */*sc*/);
+
+/* --- @error@ --- *
+ *
+ * Arguments:  @scanner *sc@ = pointer to scanner definition
+ *             @const char *msg@ = message skeleton string
+ *             @...@ = extra arguments for the skeleton
+ *
+ * Returns:    Doesn't
+ *
+ * Use:                Reports an error at the current scanner location.
+ */
+
+extern void error(scanner */*sc*/, const char */*msg*/, ...);
+
+/* --- @conf_enum@ --- *
+ *
+ * Arguments:  @scanner *sc@ = pointer to a scanner object
+ *             @const char *list@ = comma-separated things to allow
+ *             @unsigned @f = flags for the search
+ *             @const char *err@ = error message if not found
+ *
+ * Returns:    Index into list, zero-based, or @-1@.
+ *
+ * Use:                Checks whether the current token is a string which matches
+ *             one of the comma-separated items given.  If not, an error is
+ *             reported; otherwise the index of the matched item is
+ *             returned.
+ */
+
+#define ENUM_ABBREV 1u
+#define ENUM_NONE 2u
+
+extern int conf_enum(scanner */*sc*/, const char */*list*/,
+                    unsigned /*flags*/, const char */*err*/);
+
+/* --- @conf_prefix@ --- *
+ *
+ * Arguments:  @scanner *sc@ = pointer to a scanner object
+ *             @const char *p@ = pointer to prefix string to check
+ *
+ * Returns:    Nonzero if the prefix matches.
+ *
+ * Use:                If the current token is a word matching the given prefix
+ *             string, then it and an optional `.' character are removed and
+ *             a nonzero result is returned.  Otherwise the current token is
+ *             left as it is, and zero is returned.
+ *
+ *             Typical options parsing code would remove an expected prefix,
+ *             scan an option anyway (since qualifying prefixes are
+ *             optional) and if a match is found, claim the option.  If no
+ *             match is found, and a prefix was stripped, then an error
+ *             should be reported.
+ */
+
+extern int conf_prefix(scanner */*sc*/, const char */*p*/);
+
+/* --- @CONF_BEGIN@, @CONF_ACCEPT@, @CONF_END@ --- *
+ *
+ * Arguments:  @sc@ = scanner to read from
+ *             @prefix@ = prefix to scan for
+ *             @desc@ = description of what we're parsing
+ *
+ * Use:                Bracket an options parsing routine.
+ */
+
+#define CS_PLAIN 0
+#define CS_PREFIX 1
+#define CS_BRACE 2
+#define CS_UNKNOWN 3
+
+#define CONF_BEGIN(sc, prefix, desc) do {                              \
+  scanner *_conf_sc = (sc);                                            \
+  const char *_conf_desc = (desc);                                     \
+  int _conf_state = CS_PLAIN;                                          \
+  if (_conf_sc->t == CTOK_WORD &&                                      \
+      strcmp(_conf_sc->d.buf, (prefix)) == 0) {                                \
+    token(_conf_sc);                                                   \
+    _conf_state = CS_PREFIX;                                           \
+    if (_conf_sc->t == '.')                                            \
+      token(_conf_sc);                                                 \
+    else if (_conf_sc->t == '{') {                                     \
+      token(_conf_sc);                                                 \
+      _conf_state = CS_BRACE;                                          \
+    }                                                                  \
+  }                                                                    \
+  if (_conf_sc->t != CTOK_WORD)                                                \
+    error(_conf_sc, "parse error, expected option keyword");           \
+  do {
+
+#define CONF_ACCEPT goto _conf_accept
+#define CONF_REJECT goto _conf_reject
+#define CONF_QUAL (_conf_state != CS_PLAIN)
+
+#define CONF_END                                                       \
+  _conf_reject:                                                                \
+    if (_conf_state == CS_PLAIN)                                       \
+      _conf_state = CS_UNKNOWN;                                                \
+    else {                                                             \
+      error(_conf_sc, "unknown %s option `%s'",                                \
+           _conf_desc, _conf_sc->d.buf);                               \
+    }                                                                  \
+  _conf_accept:                                                                \
+    if (_conf_state == CS_BRACE && _conf_sc->t == ';')                 \
+      token(_conf_sc);                                                 \
+  } while (_conf_state == CS_BRACE && _conf_sc->t == CTOK_WORD);       \
+  if (_conf_state == CS_BRACE) {                                       \
+    if (_conf_sc->t == '}')                                            \
+      token(_conf_sc);                                                 \
+    else                                                               \
+      error(_conf_sc, "parse error, expected `}'");                    \
+  }                                                                    \
+  return (_conf_state != CS_UNKNOWN);                                  \
+} while (0)
+
+/* --- @conf_name@ --- *
+ *
+ * Arguments:  @scanner *sc@ = pointer to scanner
+ *             @char delim@ = delimiter character to look for
+ *             @dstr *d@ = pointer to dynamic string for output
+ *
+ * Returns:    ---
+ *
+ * Use:                Reads in a compound name consisting of words separated by
+ *             delimiters.  Leading and trailing delimiters are permitted,
+ *             although they'll probably cause confusion if used.  The name
+ *             may be enclosed in square brackets if that helps at all.
+ *
+ *             Examples of compound names are filenames (delimited by `/')
+ *             and IP addresses (delimited by `.').
+ */
+
+extern void conf_name(scanner */*sc*/, char /*delim*/, dstr */*d*/);
+
 /* --- @conf_parse@ --- *
  *
- * Arguments:  @void *scp@ = pointer to a scanner structure
+ * Arguments:  @scanner *sc@ = pointer to a scanner structure
  *
  * Returns:    ---
  *
  * Use:                Parses a configuration file fragment from the scanner
  */
 
-extern void conf_parse(void */*scp*/);
+extern void conf_parse(scanner *sc);
 
 /*----- That's all, folks -------------------------------------------------*/