X-Git-Url: https://jxself.org/git/?p=a56.git;a=blobdiff_plain;f=src%2Fkeybld.c;fp=src%2Fkeybld.c;h=f3d6ce6d6564433b3421dab5d487dbb23c01cbc7;hp=0000000000000000000000000000000000000000;hb=34923afb4a618598083726717bf2f20d310f4f6e;hpb=c6db6f4c5cb82f5e09472163bf11be0c165965ee

diff --git a/src/keybld.c b/src/keybld.c
new file mode 100644
index 0000000..f3d6ce6
--- /dev/null
+++ b/src/keybld.c
@@ -0,0 +1,231 @@
+/*
+ * Copyright (C) 1990-1994 Quinn C. Jensen
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appear in all copies and
+ * that both that copyright notice and this permission notice appear
+ * in supporting documentation.  The author makes no representations
+ * about the suitability of this software for any purpose.  It is
+ * provided "as is" without express or implied warranty.
+ *
+ */
+static char *Copyright = "Copyright (C) 1990-1994 Quinn C. Jensen";
+
+/*
+ * keybld - builds a finite-state parser for the given keyword list
+ *
+ */
+
+#include <stdio.h>
+#include "a56.h"
+
+char buf[1024];
+
+main()
+{
+	int line = 0;
+
+	while(gets(buf)) {
+		char *bp = buf;
+		line++;
+		while(*bp != '\t' && *bp != ' ') bp++;
+		*bp++ = '\0';
+		while(*bp == '\t' || *bp == ' ') bp++;
+		if(strcmp(buf, ".code") == 0) {
+			printf("%s\n", bp);
+		} else if(add_tok(buf, bp) == -1) {
+			fprintf(stderr, "input line %d: ambiguous\n", line);
+		}
+	}
+
+	dump_machine();
+	return 0;
+}
+
+#define MAX_CHAR 'z'
+
+#define TRANSITIONS (MAX_CHAR + 1)
+
+struct state {
+	int number;
+	char *seen;
+	struct trans {
+		char action;
+		void *arg;
+	} trans[TRANSITIONS];
+	struct state *next;
+} empty_state, *stop = NULL, *scur = NULL, *new_state();
+int n_states = 0;
+
+/* actions */
+#define NOMATCH 0	/* argument is nothing */
+#define GOTO 1		/* argument is target state */
+#define TERMINAL 2	/* argument is which user action to perform */
+
+struct user_action {
+	char *action;
+	struct user_action *next;
+} *utop = NULL, *ucur = NULL;
+int n_user_actions = 0;
+
+add_tok(tok, actions)
+char *tok, *actions;
+{
+	struct state *scur;
+	struct user_action *unew = (struct user_action *)alloc(sizeof *unew);
+	unew->action = strsave(actions);
+	unew->next = NULL;
+	if(ucur)
+		ucur->next = unew;
+	ucur = unew;
+	if(utop == NULL)
+		utop = unew;
+
+	if(stop == NULL)
+		new_state(NULL);
+
+	if(follow(*tok, tok + 1, stop) == -1)
+		return -1;
+
+	n_user_actions++;
+	return 0;
+}
+
+follow(c, tp, sp)
+char c;
+char *tp;
+struct state *sp;
+{
+	struct trans *arcp, *arcup;
+	
+	if(c >= 'a' && c <= 'z') {
+		c -= 'a' - 'A';
+	}
+	arcp = sp->trans + c;
+
+	if(c >= 'A' && c <= 'Z') {
+		arcup = sp->trans + c + 'a' - 'A';
+	} else {
+		arcup = arcp;
+	}
+
+	if(c == '\0') {
+		if(arcp->action == TERMINAL) {
+			return -1;
+		} else {
+			arcp->action = arcup->action = TERMINAL;
+			arcp->arg = arcup->arg = (void *)n_user_actions;
+			return 0;
+		}
+	} else {
+		if(arcp->action == GOTO) {
+			return follow(*tp, tp + 1, arcp->arg);
+		} else {
+			struct state *new = new_state(tp);
+			arcp->action = arcup->action = GOTO;
+			arcp->arg = arcup->arg = (void *)new;
+			return follow(*tp, tp + 1, new);
+		}
+	}
+}
+
+struct state *new_state(tp)
+char *tp;
+{
+	struct state *snew = (struct state *)alloc(sizeof *snew);
+	char tmp[1024];
+
+	*snew = empty_state;
+
+	snew->number = n_states++;
+
+	snew->next = NULL;
+
+	if(scur)
+		scur->next = snew;
+	scur = snew;
+
+	if(stop == NULL)
+		stop = snew;
+
+	if(tp) {
+		strncpy(tmp, buf, tp - buf);
+		tmp[tp - buf] = '\0';
+	} else
+		strcpy(tmp, "<nothing>");
+
+	snew->seen = strsave(tmp);
+
+	return snew;
+}
+
+dump_machine()
+{
+	struct state *sp;
+	struct user_action *up;
+	int n, a;
+
+	printf("/* state machine generated by keybld */\n");
+	printf("/* states=%d actions=%d */\n", n_states, n_user_actions);
+	printf("/* %d bytes required for transition table storage */\n",
+		sizeof(short) * TRANSITIONS * n_states);
+
+	printf("short transitions[%d][%d] = {\n", n_states, TRANSITIONS);
+	for(n = 0, sp = stop; sp; sp = sp->next, n++) {
+		printf("	/* state %d: \"%s\" */\n", n, sp->seen);
+		printf("	{");
+		for(a = 0; a < TRANSITIONS; a++) {
+			struct trans *tp = sp->trans + a;
+			switch(tp->action) {
+			case GOTO:
+				printf("%d", ((struct state *)tp->arg)->number);
+				break;
+			case TERMINAL:
+				printf("%d", -(int)tp->arg - 1);
+				break;
+			case NOMATCH:
+				printf("0");
+				break;
+			}
+			printf(",%s", a % 20 == 19 ? "\n\t\t" : "");
+		};
+		printf("},\n");
+	}
+
+	printf("};\n");
+
+	printf("\
+\n\
+kparse(kp)\n\
+char *kp;\n\
+{\n\
+	int state = 0;\n\
+\n\
+	for(;;) {\n\
+		short transition = transitions[state][*kp];\n");
+
+printf("\
+		if(transition == 0) {\n\
+			return 0;\n\
+		} else if(transition > 0) {\n\
+			kp++;\n\
+			state = transition;\n\
+		} else {\n\
+			switch(-transition) {\n");
+
+	for(n = 1, up = utop; up; up = up->next, n++) {
+		printf("\
+			case %d:\n\
+				%s;\n\
+				break;\n", n, up->action);
+	}
+
+	printf("\
+			}\n\
+			return transition;\n\
+		}\n\
+	}\n\
+}\n");
+
+}