Add POSIX implementation of regex.

This also includes documentation of the regex engine in posixregex.c,
because I couldn't think of anywhere better to put it.

diff --git a/sys/share/cppregex.cpp b/sys/share/cppregex.cpp
index e775d7c6f18d3b190d1c1a337d0aaf72cf18c479..a0a1bbdc85edf3d758ef7203b5495abc83149bc6 100644 (file)
--- a/sys/share/cppregex.cpp
+++ b/sys/share/cppregex.cpp
@@ -1,11 +1,12 @@
 /* NetHack 3.5  cppregex.cpp   $NHDT-Date$  $NHDT-Branch$:$NHDT-Revision$ */
-/* NetHack 3.5 cppregex.cpp    $Date: 2009/05/06 10:44:33 $  $Revision: 1.4 $ */
 /* Copyright (c) Sean Hunt  2015.                                 */
 /* NetHack may be freely redistributed.  See license for details. */
 
 #include <regex>
 #include <memory>
 
+/* nhregex interface documented in sys/share/posixregex.c */
+
 extern "C" {
   #include <hack.h>
 

diff --git a/sys/share/posixregex.c b/sys/share/posixregex.c
new file mode 100644 (file)
index 0000000..17cb284
--- /dev/null
+++ b/sys/share/posixregex.c
@@ -0,0 +1,92 @@
+/* NetHack 3.5  posixregex.c   $NHDT-Date: 1428590280 2015/04/09 14:38:00 $  $NHDT-Branch: scshunt-regex $:$NHDT-Revision: 1.0 $ */
+/* Copyright (c) Sean Hunt  2015.                                 */
+/* NetHack may be freely redistributed.  See license for details. */
+
+#include <hack.h>
+
+#include <regex.h>
+
+/* The nhregex interface is implemented by several source files. The
+ * file to be used can be linked in by the build.
+ *
+ * The regex standard implemented should be POSIX extended regular
+ * expressions, see:
+ *   http://pubs.opengroup.org/onlinepubs/009696899/basedefs/xbd_chap09.html
+ * If an implementation uses an alternate expression format, this should
+ * be clearly noted; this will result in incompatibility of config files
+ * when NetHack is compiled with that implementation.
+ *
+ * struct nhregex
+ * The nhregex structure is an opaque structure type containing the
+ * information about a compiled regular expression.
+ *
+ * struct nhregex *regex_init(void)
+ * Used to create a new instance of the nhregex structure. It is
+ * uninitialized and can only safely be passed to regex_compile.
+ *
+ * boolean regex_compile(const char *s, struct nhregex *re)
+ * Used to compile s into a regex and store it in re. Returns TRUE if
+ * successful and FALSE otherwise. re is invalidated regardless of
+ * success.
+ *
+ * const char *regex_error_desc(struct nhregex *re)
+ * Used to retrieve an error description from an error created involving
+ * re. Returns NULL if no description can be retrieved. The returned
+ * string may be a static buffer and so is only valid until the next
+ * call to regex_error_desc.
+ *
+ * boolean regex_match(const char *s, struct nhregex *re)
+ * Used to determine if s (or any substring) matches the regex compiled
+ * into re. Only valid if the most recent call to regex_compile on re
+ * succeeded.
+ *
+ * void regex_free(struct nhregex *re)
+ * Deallocate a regex object.
+ */
+
+struct nhregex {
+  regex_t re;
+  int err;
+};
+
+struct nhregex *regex_init() {
+  return malloc (sizeof (struct nhregex));
+}
+
+boolean regex_compile(const char *s, struct nhregex *re) {
+  if (!re)
+    return FALSE;
+  if ((re->err = regcomp(&re->re, s, REG_EXTENDED | REG_NOSUB)))
+    return FALSE;
+  return TRUE;
+}
+
+const char *regex_error_desc(struct nhregex *re) {
+  static char buf[BUFSZ];
+
+  if (!re || !re->err)
+    return NULL;
+
+  /* FIXME: Using a static buffer here is not ideal, but avoids memory
+   * leaks. Consider the allocation more carefully. */
+  regerror(re->err, &re->re, buf, BUFSZ);
+
+  return buf;
+}
+
+boolean regex_match(const char *s, struct nhregex *re) {
+  if (!re)
+    return FALSE;
+
+  int result;
+  if ((result = regexec(&re->re, s, 0, NULL, 0))) {
+    if (result != REG_NOMATCH)
+      re->err = result;
+    return FALSE;
+  }
+  return TRUE;
+}
+
+void regex_free(struct nhregex *re) {
+  free(re);
+}

diff --git a/sys/unix/Makefile.src b/sys/unix/Makefile.src
index b64a838c97d8b161faf456d1c9150fd65addd970..79d34fc64cfdbad726619c17e35b1cecc6fc4069 100644 (file)
--- a/sys/unix/Makefile.src
+++ b/sys/unix/Makefile.src
@@ -1,5 +1,5 @@
 #      NetHack Makefile.
-# NetHack 3.5  Makefile.src    $NHDT-Date$  $NHDT-Branch$:$NHDT-Revision$
+# NetHack 3.5  Makefile.src    $NHDT-Date: 1428590253 2015/04/09 14:37:33 $  $NHDT-Branch: scshunt-regex $:$NHDT-Revision: 1.38 $
 # NetHack 3.5  Makefile.src    $Date: 2012/01/20 03:41:33 $  $Revision: 1.37 $
 
 # Root of source tree:
@@ -338,7 +338,7 @@ HACKCSRC = allmain.c alloc.c apply.c artifact.c attrib.c ball.c bones.c \
 
 # all operating-system-dependent .c (for dependencies and such)
 SYSCSRC = ../sys/atari/tos.c ../sys/share/pcmain.c ../sys/share/pcsys.c \
-       ../sys/share/pctty.c ../sys/share/pcunix.c ../sys/share/random.c \
+       ../sys/share/pctty.c ../sys/share/pcunix.c ../sys/share/posixregex.c ../sys/share/random.c \
        ../sys/share/ioctl.c ../sys/share/unixtty.c ../sys/unix/unixmain.c \
        ../sys/unix/unixunix.c ../sys/unix/unixres.c ../sys/be/bemain.c
 
@@ -391,7 +391,7 @@ HOBJ = $(FIRSTOBJ) allmain.o alloc.o apply.o artifact.o attrib.o ball.o \
        minion.o mklev.o mkmap.o \
        mkmaze.o mkobj.o mkroom.o mon.o mondata.o monmove.o monstr.o \
        mplayer.o mthrowu.o muse.o music.o o_init.o objnam.o options.o \
-       pager.o pickup.o pline.o polyself.o potion.o pray.o priest.o \
+       pager.o pickup.o pline.o polyself.o posixregex.o potion.o pray.o priest.o \
        quest.o questpgr.o read.o rect.o region.o restore.o rip.o rnd.o \
        role.o rumors.o save.o shk.o shknam.o sit.o sounds.o sp_lev.o spell.o \
        sys.o \
@@ -603,6 +603,8 @@ random.o: ../sys/share/random.c $(HACK_H)
        $(CC) $(CFLAGS) -c ../sys/share/random.c
 ioctl.o: ../sys/share/ioctl.c $(HACK_H) ../include/tcap.h
        $(CC) $(CFLAGS) -c ../sys/share/ioctl.c
+posixregex.o: ../sys/share/posixregex.c $(HACK_H)
+       $(CC) $(CFLAGS) -c ../sys/share/posixregex.c
 unixtty.o: ../sys/share/unixtty.c $(HACK_H)
        $(CC) $(CFLAGS) -c ../sys/share/unixtty.c
 unixmain.o: ../sys/unix/unixmain.c $(HACK_H) ../include/dlb.h