From 00e0bcc105fb756395f386031c7f52e25fe36f1e Mon Sep 17 00:00:00 2001
From: Cody Boone Ferguson <53008573+xexyl@users.noreply.github.com>
Date: Mon, 15 May 2023 03:02:40 -0700
Subject: [PATCH] Add table generator to 1984/mullender from author

This included adding the 'a.out.h' as not all systems have it and also
I wanted it as close to the original as possible so I got a copy
(https://raw.githubusercontent.com/dspinellis/unix-history-repo/Research-Release/usr/include/a.out.h) from
the fabulous Unix History repo
(https://github.com/dspinellis/unix-history-repo) which I highly
recommend anyone interested in the evolution of Unix to check out!

... and yes: the repo is under the account of Diomidis Spinellis who is
a previous IOCCC winner!

To generate the tool run `make gentab'. Note that keeping the short ints
short generates a lot of negative numbers but this might or might not be
a problem: the original mullender.c has a negative number for instance.

Updated .gitignore and README.md files.
---
 1984/mullender/.gitignore |  1 +
 1984/mullender/Makefile   |  5 ++++
 1984/mullender/README.md  | 28 ++++++++++++++++++--
 1984/mullender/a.out.h    | 33 ++++++++++++++++++++++++
 1984/mullender/gentab.c   | 54 +++++++++++++++++++++++++++++++++++++++
 5 files changed, 119 insertions(+), 2 deletions(-)
 create mode 100644 1984/mullender/a.out.h
 create mode 100644 1984/mullender/gentab.c

diff --git a/1984/mullender/.gitignore b/1984/mullender/.gitignore
index 85c8b08ba..14a439de4 100644
--- a/1984/mullender/.gitignore
+++ b/1984/mullender/.gitignore
@@ -1,2 +1,3 @@
 mullender
 mullender.alt
+gentab
diff --git a/1984/mullender/Makefile b/1984/mullender/Makefile
index 38f359ecc..f1fab7dff 100644
--- a/1984/mullender/Makefile
+++ b/1984/mullender/Makefile
@@ -131,6 +131,10 @@ ${PROG}: ${PROG}.c
 	@echo "than a Vax-11 or pdp-11."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
+gentab: gentab.c
+	${CC} ${CFLAGS} $< -o $@ ${LIBS}
+
+
 # alternative executable
 #
 alt: data ${ALT_TARGET}
@@ -164,6 +168,7 @@ clean:
 clobber: clean
 	${RM} -f ${TARGET} ${ALT_TARGET}
 	${RM} -f core
+	${RM} -f gentab
 	@-if [ -e sandwich ]; then \
 	    ${RM} -f sandwich; \
 	    echo 'ate sandwich'; \
diff --git a/1984/mullender/README.md b/1984/mullender/README.md
index ed1a8de61..39737e044 100644
--- a/1984/mullender/README.md
+++ b/1984/mullender/README.md
@@ -17,11 +17,11 @@ make all
 ./mullender
 ```
 
-> NOTE: If your machine is not a Vax-11 or pdp-11, this program will
+> NOTE: If your machine is not a VAX-11 or PDP-11, this program will
 > not execute correctly.  In later years, machine dependent
 > code was discouraged.
 
-### Alternative code:
+### Alternate code:
 
 [Cody Boone Ferguson](/winners.html#Cody_Boone_Ferguson) added the alternative
 code which lets you run this on other systems. He notes though that this was
@@ -95,6 +95,30 @@ couldn't!  :-)
 
 BTW: this remains my (Landon Curt Noll's) all time favorite entries!
 
+Cody found the remarks from [Sjoerd Mullender](/winners.html#Sjoerd_Mullender)
+and added the program that was used by the authors to generate the array that he
+referred to. Because [a.out.h](a.out.h) is not available in all systems (like macOS) and
+more importantly because he wanted it to be as close to as the original as
+possible he used a copy of
+<https://raw.githubusercontent.com/dspinellis/unix-history-repo/Research-Release/usr/include/a.out.h>
+in the *fabulous* [Unix History
+Repo](https://github.com/dspinellis/unix-history-repo/tree/Research-Release).
+
+This tool can be built by running:
+
+
+```sh
+make gentab
+```
+
+Cody notes that it does not appear to work in modern systems (unbalanced braces)
+or something else is wrong but given that this was done a long time ago on a now
+archaic system maybe that is why. He also noted that if the `short`s are not
+changed to just `int` it prints out a lot of negative numbers but since
+[mullender.c](mullender.c) has a negative number he kept it as is.
+
+Thank you Cody!
+
 ## Author's remarks:
 
 These remarks, found at
diff --git a/1984/mullender/a.out.h b/1984/mullender/a.out.h
new file mode 100644
index 000000000..75e2ba9fa
--- /dev/null
+++ b/1984/mullender/a.out.h
@@ -0,0 +1,33 @@
+struct	exec {	/* a.out header */
+	int     	a_magic;	/* magic number */
+	unsigned	a_text; 	/* size of text segment */
+	unsigned	a_data; 	/* size of initialized data */
+	unsigned	a_bss;  	/* size of unitialized data */
+	unsigned	a_syms; 	/* size of symbol table */
+	unsigned	a_entry; 	/* entry point */
+	unsigned	a_unused;	/* not used */
+	unsigned	a_flag; 	/* relocation info stripped */
+};
+
+#define	A_MAGIC1	0407       	/* normal */
+#define	A_MAGIC2	0410       	/* read-only text */
+#define	A_MAGIC3	0411       	/* separated I&D */
+#define	A_MAGIC4	0405       	/* overlay */
+
+struct	nlist {	/* symbol table entry */
+	char    	n_name[8];	/* symbol name */
+	int     	n_type;    	/* type flag */
+	unsigned	n_value;	/* value */
+};
+
+		/* values for type flag */
+#define	N_UNDF	0	/* undefined */
+#define	N_ABS	01	/* absolute */
+#define	N_TEXT	02	/* text symbol */
+#define	N_DATA	03	/* data symbol */
+#define	N_BSS	04	/* bss symbol */
+#define	N_TYPE	037
+#define	N_REG	024	/* register name */
+#define	N_FN	037	/* file name symbol */
+#define	N_EXT	040	/* external bit, or'ed in */
+#define	FORMAT	"%06o"	/* to print a value */
diff --git a/1984/mullender/gentab.c b/1984/mullender/gentab.c
new file mode 100644
index 000000000..069cd89e7
--- /dev/null
+++ b/1984/mullender/gentab.c
@@ -0,0 +1,54 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "a.out.h"
+
+main(argc, argv) char **argv;
+{
+    register FILE *fp;
+    register short pos = 0, c, n;
+    register char *fmt = "";
+    if (argc != 2) {
+	fprintf (stderr, "Usage: %s file\n", argv[0]);
+	exit (1);
+    }
+
+    if ((fp = fopen(argv[1], "r")) == NULL) {
+	fprintf(stderr, "%s: can't open %s\n", argv[0], argv[1]);
+	exit(2);
+    }
+
+    fseek (fp, (long) sizeof (struct exec), 0); 
+    printf("/* portable between VAX and PDP11 */\n\n");
+    printf ("short main[] = {\n");
+    for (;;) {
+	if (pos == 0)
+	    printf("\t");
+
+	c=getc(fp) & 0377;
+	if (feof(fp)) break;
+	n = getc(fp) << 8|c;
+
+	switch (rand() % 5) {
+	    case 0:
+	    case 1:
+		fmt = "%d"; break;
+	    case 2:
+		fmt = "%u"; break;
+	    case 3:
+		fmt = "0%o"; break;
+	    case 4:
+		fmt = "0x%x"; break;
+	}
+
+	if (32 <= n && n < 127 && (rand() % 4)) fmt = "'%c'";
+	printf(n < 8 ? "%d" : fmt, n);
+	printf(",");
+	if (pos++ == 8) {
+	    printf("\n");
+	    pos = 0;
+	}
+	else printf(" ");
+
+	printf("};\n");
+    }
+}